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Kosmos
Astronomia Astrofizyka
Inne

Kultura
Sztuka dawna i współczesna, muzea i kolekcje

Metoda
Metodologia nauk, Matematyka, Filozofia, Miary i wagi, Pomiary

Materia
Substancje, reakcje, energia
Fizyka, chemia i inżynieria materiałowa

Człowiek
Antropologia kulturowa Socjologia Psychologia Zdrowie i medycyna

Wizje
Przewidywania Kosmologia Religie Ideologia Polityka

Ziemia
Geologia, geofizyka, geochemia, środowisko przyrodnicze

Życie
Biologia, biologia molekularna i genetyka

Cyberprzestrzeń
Technologia cyberprzestrzeni, cyberkultura, media i komunikacja

Działalność
Wiadomości | Gospodarka, biznes, zarządzanie, ekonomia

Technologie
Budownictwo, energetyka, transport, wytwarzanie, technologie informacyjne

American Journal of Engineering and Applied Sciences

Problem statement: Low complexity image compression algorithms are necessary for modern portable devices such as mobile phones, wireless sensor networks and high constraint power consumption devices. In such applications low bit rate along with an acceptable image quality are an essential requirements. Approach: This study proposes low and moderate complexity algorithms for colour image compression. Two algorithms will be presented; the first one is intensity based adaptive quantization coding, while the second is a combination of discrete wavelet transforms and the intensity based adaptive quantization coding algorithm. Adaptive quantization coding produces a good Peak Signal to Noise Ratio (PSNR), but with high bit rates compared with other low complex algorithms. The presented algorithms produce low bit rate whilst preserving the PSNR and image quality at an acceptable range. Results: Experiments were performed using different kinds of standard colour images, a multi level quantizer, different thresholds, different block sizes and different wavelet filters. Both algorithms considered the intensity variation of each colour plane. At high compression ratios the proposed algorithms produced 1-3 bpp bit rate reduction against the stand alone adaptive quantization coding for the same image quality. This reduction was achieved due to dropping of some blocks that claimed to be low intensity variation according to a comparison with predefined thresholds for each colour plane. The results show that the bit rate can be reduced by 72-88% for each low variation image block from the original bit rate. Conclusion: The results obtained show a good reduction in bit rate with the same PSNR, or a slightly less than PSNR of a standalone adaptive quantization coding algorithm. Further bit rate reduction has been achieved by decomposing the input image using different wavelet filters and intensity based adaptive quantization coding. The proposed algorithm comprises a number of parameters to control the performance of the compressed images.

http://www.thescipub.com/abstract/10.3844/ajeassp.2011.504.512 2012/01/18 - 11:48

Problem statement: Similar to other baseband modulation schemes, the performance of the Dual Header Pulse Interval Modulation (DH-PIM) is adversely affected by Artificial Light Interferences (ALI) in an indoor Optical Wireless Communications (OWC) channel. Approach: The Discrete Wavelet Transform (DWT) based denoising is studied for reducing the effect of the ALI. Computer simulation is carried out to demonstrate the effectiveness of the proposed system. The Baseline Wander (BLW) affects for a range of bit resolutions is also analyzed. Results: The normalized optical power requirement in the presence of ALI is high in the range of 9-15 dB depending upon the bit resolution. A significant reduction in the optical power penalty is observed with the DWT denoising scheme. Conclusion: The DWT based denoising scheme is effective in reducing the consequence of the ALI. The optical power penalty decreases with an increase in the data rate and the bit resolution, which is due to reduction of the DC values and low frequency spectrum.

http://www.thescipub.com/abstract/10.3844/ajeassp.2011.513.519 2012/01/18 - 11:48

Problem statement: The optical signal propagating through the Free Space Optical (FSO) channel suffers from irradiance and phase fluctuations caused by the atmospheric turbulence, which results in Bit Error Rate (BER) performance degradation. Approach: In this study the performance of the Multilevel Coherent Polarization Shift Keying (M-POLSK) based FSO communication system operating over the gamma-gamma turbulence channel is investigated. To mitigate the turbulence induced fading, the convolutional coding and spatial diversity techniques are employed. The upper BER bounds are derived using the transfer function technique. Results: For example, with a SNR of 30 dB, the BERs for uncoded and coded M-POLSK are 0.047 and 1.4×10-4, respectively in the weak turbulence regime. When the Maximum Ration Combining (MRC) technique employing four detectors are used in the receiver, the power gains of ∼31.4, ∼29.5 and ∼57.9 dB are achieved for weak, moderate and strong turbulence regimes, respectively. Conclusion: We have also shown that the spatial diversity offers increased link margin as the scintillation level rises. Compared to the angular modulation, the proposed M-POLSK scheme offers high immunity to the phase noise, thus reducing the power penalties.

http://www.thescipub.com/abstract/10.3844/ajeassp.2011.520.530 2012/01/18 - 11:48

Problem statement: Wired broadband Internet access can be realized using various technologies, configurations and protocols. It is widely deployed and able to provide both high data rates and high reliability. These features are of strong importance for many advanced applications. Since the number of broadband subscribers worldwide grows exponentially, the power efficiency of access networks becomes increasingly important. Approach: The aim of this study is to study power consumption of different wired broadband access technologies including both those already widely used and those which are state-of-the-art, but not yet widely deployed. For this purpose, we developed a model for evaluating energy efficiency of wired access networks. The model is presented and applied to study energy efficiency of various access networks such as Hybrid Fiber Coax (HFC), Digital Subscriber Line (DSL), 1 and 10 Gbit/s point-to-point ethernet and Passive Optical Networks (1G-PON and 10G-PON). The metric for energy efficiency we used in this study is energy consumed per bit transmitted. Results: Results of the comparative study on energy efficiency of different access networks are shown and discussed. Additionally, we estimated environmental implications of different access options by means of reductions in Green House Gas (GHG) emissions caused by the electricity consumption of access network infrastructure. Conclusion: We found out that high-speed optical access technologies providing up to 10 Gbit/s per user have the potential to achieve the highest energy efficiency when assuming future broadband Internet access and broad use of advanced services and applications. However, for lower access data rates, 1G-PONs are the most energy efficient access options. Coper-based access technologies provide generally lower energy efficiency than the fiber based solutions. For transferring a large amount of data and when network equipment is switched off during its inactivity times, optical access technologies have the highest potential to reduce GHG emissions caused by the electricity consumption of access network infrastructure.

http://www.thescipub.com/abstract/10.3844/ajeassp.2011.531.539 2012/01/18 - 11:48

Problem statement: This study aimed at evaluating and beneficiating Bentonitic clays of Pindiga Formation from the upper Benue trough in northeastern Nigeria to meet the standard required for use in oil well drilling. This will reduce the dependence on imported Bentonite into the country, increase foreign exchange, improve the country‘s economy and create employment opportunities. Approach: Three clay samples from different locations within Pindiga Formation were collected using standard sampling procedure and brought to the laboratory for the study. Evaluation of Loss On Ignition (LOI) was carried out using “Labocon” Furnace (model 2-1200), elemental composition of the samples were determined using Instrumental Neutron Activation Analysis (INAA) and X-Ray Fluorescence (XRF) while mineralogical phases of the samples were determined by X-Ray Diffractometry. Results: Results of analysis of crude Bentonitic clays indicates that the clays are Ca-based which require some level of beneficiation before they can attain the properties that will qualify its use in oil well drilling, while other properties such as Aluminum-Silicon ration which ranges between 0.34-0.39 as against 0.38 for the standard Wyoming Bentonite, LOI ranges between 14.8-15.63 as against 15.73 for the standard and fineness of the samples all attained the required standard even before beneficiation. After beneficiating the samples, their rheological and other physical properties was found to have improved to a level that is acceptable for use in oil well drilling except for yield points which was still lower. Maximum values recorded for viscosity and yield points for crude and beneficiated samples at 300 and 600 rpm are 5, 34.5 and 3, 9 while 15 was recorded for floating drill cuttings, respectively. API has specified the viscosity and yield to be ≥30 for viscosity at 600 rpm and yield point at ≤3. Conclusion: This result indicates that Bentonitic clays from Pindiga Formation in Benue trough, northeastern Nigeria are Ca-base but can be beneficiated using sodium carbonate as beneficiating agent and ion exchange procedure.

http://www.thescipub.com/abstract/10.3844/ajeassp.2011.497.503 2012/01/17 - 13:50

Problem statement: For the Orthogonal Frequency Division Multiple Access (OFDMA) downlink of a femto network, the resource allocation scheme would aim to maximize the Area Spectral Efficiency (ASE) subject to constraints on the radio resources per transmission interval accessible by each femtocell. Approach: An optimal resource allocation scheme for completely decentralized femtocell deployments leads to a nonlinear optimization problem because the cost function of the optimization problem is nonlinear. In this study, an adaptive gradient vector step size approach is proposed for finding the optimal solution of the optimization problem. Results: Computer numerical simulation results show that our proposed method is more efficient than existing exhaustive search methods. Conclusion: By adpative changing the step size of the gradient vector, the locally optimal solution can be achieved quickly.

http://www.thescipub.com/abstract/10.3844/ajeassp.2011.491.496 2012/01/15 - 01:41

Problem statement: This study derives the optimal motion vector with arbitrary pixel precisions in a single step. Approach: A non-linear block matched motion model was proposed. Based on the proposed non-linear block matched motion model, the optimal motion vector which minimizes the mean square error was solved analytically in a single step via a gradient approach. Results: The mean square error based on the proposed method was guaranteed to be lower than or equal to that based on conventional methods. The computational efforts for the proposed method were lower than that of conventional methods particularly when the required pixel precision is higher than or equal to the quarter pixel precisions. Conclusion: As integer pixel locations, half pixel locations and quarter pixel locations are particular locations represented by the proposed model, the mean square error based on the proposed method is guaranteed to be lower than or equal to that based on these conventional methods. Also, as the proposed method does not require searching from coarse pixel locations to fine pixel locations, the computational efforts for the proposed method are lower than that of the conventional methods.

http://www.thescipub.com/abstract/10.3844/ajeassp.2011.448.460 2012/01/13 - 05:24

Problem statement: Due to significant developments in the processing power and parallel processing technologies, the existing encryption algorithms are increasingly susceptible to attacks, such as side-channel attacks, for example. Designing new encryption algorithms that work efficiently on different platforms and security levels to protect the transmitted data from any possible attacks is one of the most important issues in today’s information and network security. The aim is to find more secure, reliable and flexible systems that can run as a ratified standard, with reasonable computational complexity for a sufficient service time. To expand the longevity of the algorithm, it is important to be designed to work efficiently on a variety of block sizes and key lengths according to the security demand. A sensible solution is the suggested use of a parameter transform. Approach: The present study evaluates the appropriateness of the New Mersenne Number Transform for security applications by analyzing and estimating its avalanche and diffusion power. Results: The results confirm that the transform in general reflects good avalanche characteristics that are for most cases over 50% and can be up to 100%. The lower bound can be further improved by increasing the modulus and/or the transform length. Conclusion: This New Mersenne Number Transform is highly flexible and adaptable for this application. It can be involved in the design of a secure cryptosystem for the following reasons; changing a single input element makes drastic changes in the output elements and vice versa (sensitivity), provides variable block size and key length (parameterization). Has long transform length (power of two), is error free and its inverse is the same with a scale factor of (1/N) which simplifies implementation of both encryption and decryption. Finally, it is appropriate for real time implementations such as fast algorithms, which can be applied to it, to speed up processing.

http://www.thescipub.com/abstract/10.3844/ajeassp.2011.461.469 2012/01/13 - 05:24

Problem statement: This study presents a wireless sensor node dedicated for in-tire pressure and temperature monitoring. Additional features set it apart from the many different systems available on the highly competitive market. State-of-the-art implementations are mounted on the rim of a tire. Here the sensor node will be mounted on the inner liner of the tire. By moving the sensor node from the rim to the inner liner, new challenges in the analog design arise. Approach: To implement this sensor node new power supply methods are investigated. Next, analog designs with the focus on low power are developed. Since the sensor node is operated in a harsh environment, robustness is a key issue. Results: The discussed sensor is capable of either active or passive communication. The passive communication is used in the field of Radio Frequency Identification (RFID), whereas active communication is used to transmit the sensor data. A combination of both is also possible. To supply the chip in the tire an RF energy harvesting interface is implemented. An input sensitivity of -19.7dBm for the harvesting interface and -12.5 dBm for the RFID interface is measured. The on-chip temperature sensor consumes 4μA including the analog to digital converter. Conclusion: Choosing the discussed sensor node for in-tire monitoring enables new fields of applications. With this sensor node sensing additional parameters like road condition is possible. Using passive communication improves warehouse management for tire manufactures. Also, tire type identification at the car is enabled.

http://www.thescipub.com/abstract/10.3844/ajeassp.2011.470.476 2012/01/13 - 05:24

Problem statement: In this research, four reduced End Plate Moment Connection (EPMC) specimens (T-stubs) are tested to verify the numerical and theoretical methods for preanalysis of the Low Cycle Fatigue (LCF) behavior of a four-bolt extended unstiffened EPMC. Approach: The T-stub specimens are bolted to a support frame and a monotonic load is applied to the stem plate. Yield line theory and the Kennedy method are used to analyze the strength of the end plates and bolts. The Finite Element Model (FEM) and experimental tests are used to verify the theoretical calculations. Results: The theoretical calculations, FEM results and experimental test results show reasonable relationships. Conclusion: The theoretical calculations could be used to predict LCF behavior of specimens.

http://www.thescipub.com/abstract/10.3844/ajeassp.2011.477.484 2012/01/13 - 05:24

Problem statement: In study the impact of the optical technologies and infrastructures on the reduction of the carbon footprint maintaining high level of broadband to the end user is discussed. Approach: Authors analyze the main energy consumers in Core, Metro and Access Networks as well as the topology and the performaces of the EU FP7 SARDANA Project, a long reach full optical metro access convergent network. This permit to have a clear and innovative view on the topic of the green networks comparing commercial and on the edge solutions for the critical access segment. Three scenarios have been assumed with different uplink bandwidths: unlimited uplink in the CO, limited uplink of 400 Gbit sec-1 and strong limitation of 100 Gbit sec-1. Additionally, three different sizes of the access network with 100, 1,000 and 10,000 subscribers connected to a single CO have been considered. Results: Increasing the number of users and reducing the uplink bandwidth, the difference in energy efficiency between TDM and PONs and P-t-P FTTH networks increases. Conclusion: Authors conclude that in general, a SARDANA like network provides very good energy efficiency for both limited and unlimited uplink and for small and large networks.

http://www.thescipub.com/abstract/10.3844/ajeassp.2011.485.490 2012/01/13 - 05:24

Problem statement: The integrity of deck joints in highway bridges plays a major role to determine overall performance of bridge system. As the bridge maintenance program, the defects in deck joints have historically been detected by conventional non-destructive testing and evaluation methods such as visual inspection, chain-dragging and by the detecting sounds under the traffic. Future bridge maintenance challenges will demand the development of techniques and procedures to detect and monitor such defects before they become apparent. Approach: Two non-destructive methods; namely Ground Penetration Radar (GPR) and Seismic Properties Analyzer (SPA) were employed to assess the integrity of deck joins installed in North Carolina bridges. Results: The results obtained with the GPR and SPA allows to quantify the subsurface defects in bridge deck joints. Conclusion: The practical application and limitations of each method are discussed in this study.

http://www.thescipub.com/abstract/10.3844/ajeassp.2011.440.447 2011/12/31 - 20:48

Problem statement: The role of aeration in activated sludge process is to provide oxygen to microorganisms as they assimilate the organic carbon compounds and digest a portion of them to carbon dioxide and water, sulfate and nitrate compounds. The water aeration equipment used in this process consumes as much as 60-80% of total power requirements in modern wastewater treatment plants. Approach: The objective of this study is to enhance the oxygen transfer in aeration tank in activated sludge process by increasing pressure inside the part of aeration tank to increase the saturation level of dissolved oxygen in wastewater. The diffuser cap model is the experimental model which was used to show the effect of increasing pressure on oxygen transfer level. Three cases were considered, the first used without diffuser cap, the second with diffuser cap and the third with diffuser cap and plastic strips. Results: Obtained results show that in case of using the model with diffuser cap enhanced the oxygen level by about 5% than in case of without diffuser cap while that of adding plastic strips enhanced the oxygen level by about 7%. The variation of water flow showed that increasing water flow rate from 1-2 L min-1 decreased the oxygen saturation level by about 6%. Furthermore, increasing water depth from 15-60 cm increased the oxygen level by about 40%. Conclusion: The diffuser cap model showed that the increase of pressure and water depth increased the dissolved oxygen level while increasing water flow rate decreased the dissolved oxygen level.

http://www.thescipub.com/abstract/10.3844/ajeassp.2011.435.439 2011/12/21 - 19:14

Problem statement: There is no point producing cereal threshing models that cannot replicate its performance on the field. The frictional impact that occurs between the crop surface and threshing cylinder has been often neglected by most researchers in cereal threshing. Approach: Study proffers a solution to this issue by developing a model for threshing which in-cooperate friction. This was done by analyzing the crop/threshing cylinder behavior, hence establishing mathematical sub-models to characterize the performance of this model. Results: The model was further packaged with computer aided software based on visual basic programming language and finally applied. Conclusion: Upon application, it was discovered that at a moisture content of 15% v = 9 m sec-1, Q = 0.18 kg sec-1 the model yielded performance characteristics as Eff = 88.22%, TNL = 11.78% and CAPTH = 211.52 kg h-1.

http://www.thescipub.com/abstract/10.3844/ajeassp.2011.405.412 2011/11/30 - 10:47

Problem statement: With the increasing use and awareness of pavement management systems and the growing emphasis on asset management of pavement infrastructure, it is important to strengthen the maintenance components of these systems and particularly the preventive maintenance component. Iraqi Roads don’t receive an effective and proper maintenance during their service life until they reach the state of major failure that requires rehabilitation. Roads in Iraq are being lost. Approach: In this study, a study of the status of maintenance methods for road pavements in Iraq with special reference to flexible pavements is presented. For this purpose, open and closed questionnaires were executed in Baghdad to investigate the status of road pavement maintenance in Iraq. Road maintenance offices as (Ministry of construction and Housing, State Corporation for Roads and Bridges, Amanat Baghdad, Project office,) were included in the questionnaire to arrive at the level of maintenance and techniques followed to maintain paved road in Iraq. Results: The interviews carried out reveal that maintenance in Iraq has secondary importance, apparently with no special budget allocated for such important works. In addition the maintenance methods and techniques followed do not comply the developments and modern techniques. Conclusion/Recommendations: Poor and miss-management of maintenance works and activities leading to delays and accumulation of failure in the highway network that require unusual expenditures to repair and maintain the accumulated damages. Also shortages in resources allocated for maintenance works and this leads to the diversion of significant portion of the allocated fund for maintenance works toward purchasing of new, or additional equipment to be used for the construction of new roads. It is strongly recommended to design a planning system for management pavement maintenance of road network in Iraq and develop a particular failure criterion for roads in Iraq.

http://www.thescipub.com/abstract/10.3844/ajeassp.2011.413.424 2011/11/30 - 10:47

Problem statement: Multiple-Input Multiple-Output systems (MIMO) are regarded as one of the most promising technologies in field of wireless communication. Generally considered as one of the several forms of smart antenna technology, it offers considerable increase in data throughput and link range without additional bandwidth or transmit power. The general Idea involves the use of several antennas at the transmitter and the receiver to improve system performance. One of the approaches employed in combating ISI in MIMO transmission is through the use of equalizers. Approach: In this study a proposed MIMO system is simulated using MATLAB software. The different Equalization schemes Zero Forcing (ZF) equalizer and Minimum Mean Square Error (MMSE) which aid in the elimination of Inter Symbol Interference (ISI) thus improving overall performance were compared to analyze the BER of the designed system. Results: From the simulation results, the MMSE equalizer clearly has a better performance over the ZF equalizer in the region of about 3 dB. Conclusion: MIMO transmission with MMSE equalization offers greater performance over ZF equalization. This helps in nullifying the effects of ISI thus improving overall performance. Thorough understanding of these techniques provides a good platform for future research in areas such as MIMO-OFDM.

http://www.thescipub.com/abstract/10.3844/ajeassp.2011.425.428 2011/11/30 - 10:47

Problem statement: The Software Communications Architecture (SCA) was developed to improve software reuse and interoperability in Software Defined Radios (SDR). However, there have been performance concerns since its conception. Arguably, the majority of the problems and inefficiencies associated with the SCA can be attributed to the assumption of modular distributed platforms relying on General Purpose Processors (GPPs) to perform all signal processing. Approach: Significant improvements in cost and power consumption can be obtained by utilizing specialized and more efficient platforms. Digital Signal Processors (DSPs) present such a platform and have been widely used in the communications industry. Improvements in development tools and middleware technology opened the possibility of fully integrating DSPs into the SCA. This approach takes advantage of the exceptional power, cost and performance characteristics of DSPs, while still enjoying the flexibility and portability of the SCA. Results: This study presents the design and implementation of an SCA Core Framework (CF) for a TI TMS320C6416 DSP. The framework is deployed on a C6416 Device Cycle Accurate Simulator and TI C6416 Development board. The SCA CF is implemented by leveraging OSSIE, an open-source implementation of the SCA, to support the DSP platform. OIS’s ORBExpress DSP and DSP/BIOS are used as the middleware and operating system, respectively. A sample waveform was developed to demonstrate the framework’s functionality. Benchmark results for the framework and sample applications are provided. Conclusion: Benchmark results show that, using OIS ORBExpress DSP ORB middleware has an impact for decreasing the Software Memory Footprint and increasing the System Performance compared with PrismTech's e*ORB middleware.

http://www.thescipub.com/abstract/10.3844/ajeassp.2011.429.434 2011/11/30 - 10:47

Problem statement: Nowadays, the use of waste tyre in concrete has become technically feasible and the tyre mixed concrete is light weight and called as rubberized concrete. Still the research is going on to explore basic Engineering Properties such as Transport Properties viz, Acid Absorption Test, Water Absorption Tests, Impact Resistance, Modulus of Elasticity, Dynamic Modulus and so on. In this study, the studies are limited to Acid Absorption Test, Water Absorption Test and Energy Absorbed by Impact. Approach: Experimental Investigations were conducted on tyre fiber specimens with different variables such as Length, Diameter of Holes and percentage of coarse aggregate replacement by tyre fibers. Impact Resistance Test was done by ACI standard and Acid and Water Absorptions Tests were conducted by Indian Standard. Results: In this study, Experimental results based on the water absorption, acid resistance and impact resistance of the rubberized concrete were analyzed. These experiments were conducted on rubberized concrete with tyre fibers mixed in different sizes and proportions by weight with the coarse aggregate. The specimens were immersed in water and in diluted HCL (5% concentration) acid for 28 days and tested. Conclusion: The results obtained from the tests were used to determine the optimum size of the tyre fiber specimen that could be used in the rubberized concrete mixture to give the optimum performance. The rubberized concrete with tyre fiber specimen L50-D5 10% has shown good transport characteristics and impact resistance.

http://www.thescipub.com/abstract/10.3844/ajeassp.2011.400.404 2011/10/01 - 09:13

Problem statement: This study investigates a novel optimized scheme of a High Frequency Signal Injection (HFSI) based sensorless technique in order to carry out a precise and robust rotor position error estimation of a Permanent Magnet Synchronous Motor (PMSM) drive designed for washing machines. The study is carried out for standstill condition, where precise position information is required for this application. Approach: In order to get rotor position error information, a PMSM high frequency model is considered in the estimated rotor reference frame (d,q). Then, the impact of the HFSI technique parameters choice on the PMSM rotor position estimation performance is studied and experimentally tested, under various injection conditions. Results: The experimental results show that the amplitude of the high frequency current, resulting from injection, is not significant to carry out high performance rotor position estimation. In order to improve rotor position estimation performance and robustness, a modified demodulation of the high frequency current resulting from injection is proposed by using a high pass filter amplifier applied to PMSM measured currents. The novel proposed rotor position error extraction scheme is implemented on a dsPIC30F6010A and is experimentally validated on a 1kW washing salient pole PMSM. Conclusion: This study presents an improved high frequency voltage injection based sensorless control for Permanent Magnet Synchronous Motor (PMSM) designed for washing machines. The optimal parameters choice of the HFSI technique and the use of a high pass filter amplifier have allowed to take the most of the high frequency injected signal for extracting the rotor position error at standstill, compared to a conventional scheme.

http://www.thescipub.com/abstract/10.3844/ajeassp.2011.390.399 2011/10/01 - 09:13

Problem statement: The most important design criterion of mechanized device is safety; safety comprises both the safety of operator and safety of maintenance personnel. Failures and safety of harvesting platform of Tractor Mounted Hydraulic Elevator (TMHE) powered by tractor PTO was tested by Finite Element Method for the mechanical harvesting of coconut orchards using digital Ergonomic hart rate meter. The objective of this study was to study the stability of the THME by finite element method, operational safety and power requirement for the use of this elevator for coconut harvesting. Also to provide sufficient adjustment and space to account for variation in body sizes, ensure controls are situated within suitable reach and are properly marked. Approach: The Modal analysis was carried out for the whole assembly of tractor mounted hydraulic elevator by using Ansis software. The digital polar hart rate meter RS400TM having infrared connectivity sensor is used for recording the hart rates. The research work was conducted at, Dr. Balasaheb Sawant Kokan Krishi Vidyapeeth Dapoli. The harvesting of coconuts was performed by manual climbing labor and by tractor mounted hydraulic elevator. The technical assessments included the use of biomechanical models, vibration testing equipment, ODR, BPDS. The ergonomical evaluation results of the above study are correlates to decide the feasibility, safety and efficiency of Tractor mounted hydraulic elevator for coconut harvesting. The PTO rpm influence for the lifting and lowering of the harvesting platform was studied experimentally by using digital tachometer. Results: The better stability results with the controlled vibrations and frequency of the lifting platform and welded joints were recorded by keeping constrained boundary conditions. Ergonomically operational safe and controlled heart rates are recorded. Hence the labors can continuously do the coconut harvesting work by using the tractor mounted hydraulic elevator. The minimum PTO power is required for the coconut harvesting by using tractor mounted hydraulic elevator. Conclusion/Recommendation: The tractor mounted hydraulic elevator is suitable, safe, less hazardous and economical as compared to manual climbing for coconut harvesting. Hence it is recommended to use tractor mounted hydraulic elevator for harvesting, cleaning and breeding of coconut orchards upto 14 m height.

http://www.thescipub.com/abstract/10.3844/ajeassp.2011.380.389 2011/09/20 - 18:39

Problem statement: The miniaturization of components plays an important role for manufacturing in electrical and electronic industries. Therefore, the joining technology of thin metal sheets has been strongly required. Laser welding with micro-beam and high-speed scanning is a promising solution in micro-welding, because it has high-potential advantages in welding heat sensitive components with precise control of heat input and minimal thermal distortion. Approach: In this study, the characteristics of laser micro-welding of thin stainless steel sheets by using a single-mode CW fiber laser with high-speed scanning system were experimentally investigated. Results: It was clarified that the welding bead width and depth increased with increasing the scanning velocity under a constant energy density condition and high efficient welding was expected by using high-speed laser scanning with Galvano scanner. The utilization of shielding gas is very effective to obtain smooth fusion bead and the combination of micro beam spot and high-speed laser scanning made it possible to obtain good overlap welding of ultra-thin stainless steel sheets. Conclusion: A faster and high quality welding could be achieved by using a single-mode fiber laser with micro-beam and high-speed scanning.

http://www.thescipub.com/abstract/10.3844/ajeassp.2011.314.320 2011/08/23 - 16:38

Problem statement: The heart is the first organ and most importantly to form in the body, where is found the most powerful generator of electromagnetic energy in the human body. Electrophysiology is the best method used to diagnose human heart problem. Knowledge of the electrical potentials in human heart is a quantum leap in the science of the human heart. Recently, there has been a growing interest in studying the human ECG. However, is unfortunately a very complicated issue which requires a relatively good understanding of everything that has been said about the heart. Focus on the review of physical, electromagnetic basis of human heart's biopotentials and understanding the basic equations of cardiac electrophysiology that represents the basis to all clinicians whether in postnatal (pediatric or adult) or prenatal (foetal) Medicine. Approach: Mathematical method used for derivation of the essential equations of human heart electrical potentials, this equation will develop the principle sciences of human heart, the equation also outlier finding of the electromagnetic base of human electrophysiology. Results: Heart is important electrical generator in human body. The voltage and current which was generated in human heart represent the basis of heart biosciences. The electromagnetic energy of the heart not only envelops every cell of the human body, but also extends out in all directions in the space around human body. Conclusion: The proposed technique for electrophysiology and potentials on human ECG was useful and the results may contribute to the references for later studies.

http://www.thescipub.com/abstract/10.3844/ajeassp.2011.321.327 2011/08/23 - 16:38

Problem statement: Unmatched combination of emitter and base contact resistance will influence the total performance of the solar cell. To optimize this combination, single crystalline silicon solar cell was analyzed using quasi-one-dimensional transport of electrons and holes in crystalline semiconductor, PC1D. Approach: Effects of the resistance of the emitter and base contact have been investigated with a view to find the best resistive combinations. A range of contact resistance of emitter and base were applied to PC1D software for evaluation. Results: The short circuit current Isc, the open circuit voltage Voc, the maximum power Pm and the fill factor are the observed parameters due to the variations of the resistance on the emitter and base contact. As the two variable factors that take into the account, while evaluating one factor, the other was set to constant value. It is found that as the contact resistance goes higher, the values of the parameters deceased. Conclusion/Recommendations: From the evaluation, the lowest emitter resistance that will give highest value of parameter in the selected ranged is 1 mΩ while for the base contact will be 15 mΩ. The overall investigation on single crystalline silicon solar cell base and emitter contact were done, gives potential parametric suggestion that may assist in the fabrication of high efficiency single crystalline silicon solar cells. A different range of resistance variation are suggested for future related investigation.

http://www.thescipub.com/abstract/10.3844/ajeassp.2011.328.331 2011/08/23 - 16:38

Problem statement: Accounting for uncertainties that are present in geometric and material data of reinforced concrete buildings is performed in this study within the context of performance based seismic engineering design. Approach: Reliability of the expected performance state is assessed by using various methodologies based on finite element nonlinear static pushover analysis and specialized reliability software package. Reliability approaches that were considered included full coupling with an external finite element code and surface response based methods in conjunction with either first order reliability method or importance sampling method. Various types of probability distribution functions that model parameters uncertainties were introduced. Results: The probability of failure according to the used reliability analysis method and to the selected distribution of probabilities was obtained. Convergence analysis of the importance sampling method was performed. The required duration of analysis as function of the used reliability method was evaluated. Conclusion/Recommendations: It was found that reliability results are sensitive to the used reliability analysis method and to the selected distribution of probabilities. Durations of analysis for coupling methods were found to be higher than those associated to surface response based methods; one should however include time needed to derive these lasts. For the reinforced concrete building considered in this study, it was found that significant variations exist between all the considered reliability methodologies. The full coupled importance sampling method is recommended, but the first order reliability method applied on a surface response model can be used with good accuracy. Finally, the distributions of probabilities should be carefully identified since giving the mean and the standard deviation were found to be insufficient.

http://www.thescipub.com/abstract/10.3844/ajeassp.2011.332.340 2011/08/23 - 16:38

Problem statement: In this research, we addressed the problem of minimizing the earliness-tardiness penalties and manufacturing costs of a single machine with a stochastic controllable processing and tooling cost. Approach: We developed a mathematical non-linear integer programming model and its linearised version to find the optimal solution. We introduced a new genome representation in single machine scheduling literature that evolved by a genetic algorithm to solve the problem. The genome representation includes two genes per job, one represents the job starting time and other corresponds to the job processing time. The algorithms were compared based on the solution quality, CPU time and memory consumption in bytes on a set of randomly generated test problems. Results: The results showed that developed algorithms could define the global optimal solution of most scheduling problems with n ≤ 20 jobs. For larger n, the developed genetic algorithm outperforms the math models in terms of solution quality and less CPU seconds while consumes moderate memory kilobytes of 3295 compared with 5058 and 1685 of linear and nonlinear models on the average. Conclusion: The GA's average performance achieves 6.013 related to the lower bound of math linear program whereas nonlinear model achieves an average of 1.034. The GA's performance increases by increasing n compared with other techniques. We hope to expand the developed algorithms for different configurations as parallel and job shops.

http://www.thescipub.com/abstract/10.3844/ajeassp.2011.341.349 2011/08/23 - 16:38

Problem statement: Main purpose of this study was to investigation toothed gear loading problems using the Finite Element Method. Approach: We used Niemann's equations to compare maximum bending stress which was developed at critical gear-tooth flank point during gear meshing, applied for three distinct spur-gear sizes, each having different teeth number, module and power rating. Results: The results emerging after the application of Niemann's equations were compared to the results derived by application of the Finite Element Method (FEM) for the same gear-loading input data. Results are quite satisfactory, since von Mises' equivalent stresses calculated with FEM are of the same order with the results of classical analytical method. Conclusion: Judging from the emerging results, deviation of the two methods, analytical (Niemann's equations) and computational (FEM), referring to maximum bending stress is fairly slight, independently of the applied geometrical and loading data of each gear.

http://www.thescipub.com/abstract/10.3844/ajeassp.2011.350.354 2011/08/23 - 16:38

Problem statement: As we may not be aware that the coastal construction is different from inland construction. Building in a coastal environment is different from building in an inland area. In general, buildings in coastal areas must be designed and built to withstand higher loads due to its more extreme conditions. Nowadays, the issue of global warming, uncertainty of global weather and the climate change effect indirectly creating the coastal area with much more expose to extreme condition. Formulate initial guidelines with certain degree of details how coastal construction requirements are different from those for inland construction. Approach: Due to the exposure to higher loads and extreme conditions, these structures in coastal areas will cost more to design, construct, maintain, repair and insure. Proper and right usage of building materials including electrical and mechanical equipments, are crucial in order to minimize damage. Nowadays, the issue of global warming, uncertainty of global weather and the climate change effect indirectly creating the coastal area with much more expose to extreme condition. Feedback has been gathered from the government local engineers who are doing the management of the Government’s local buildings located along the coastal area of Peninsular Malaysia. Data findings through research method, discussion with the suppliers and discussion with coastal buildings maintenance crews also has been done. Results: The research finding discus the specific characteristics that makes for successful coastal buildings focusing in tropical region. Conclusion: We must accept on the idea of building in coastal areas will require more maintenance and upkeep. By having proper coastal building guideline may create more positive awareness in constructing better management coastal buildings and can save time and money to maintain the said structures.

http://www.thescipub.com/abstract/10.3844/ajeassp.2011.307.313 2011/08/22 - 19:14

Problem statement: Unmatched combination of emitter and base contact resistance will influence the total performance of the solar cell. To optimize this combination, single crystalline silicon solar cell was analyzed using quasi-one-dimensional transport of electrons and holes in crystalline semiconductor, PC1D. Approach: Effects of the resistance of the emitter and base contact have been investigated with a view to find the best resistive combinations. A range of contact resistance of emitter and base were applied to PC1D software for evaluation. Results: The short circuit current Isc, the open circuit voltage Voc, the maximum power Pm and the fill factor are the observed parameters due to the variations of the resistance on the emitter and base contact. As the two variable factors that take into the account, while evaluating one factor, the other was set to constant value. It is found that as the contact resistance goes higher, the values of the parameters deceased. Conclusion/Recommendations: From the evaluation, the lowest emitter resistance that will give highest value of parameter in the selected ranged is 1 mΩ while for the base contact will be 15 mΩ. The overall investigation on single crystalline silicon solar cell base and emitter contact were done, gives potential parametric suggestion that may assist in the fabrication of high efficiency single crystalline silicon solar cells. A different range of resistance variation are suggested for future related investigation.

http://www.thescipub.com/abstract/10.3844/ajeassp.2011.320.323 2011/08/19 - 05:24

Problem statement: The miniaturization of components plays an important role for manufacturing in electrical and electronic industries. Therefore, the joining technology of thin metal sheets has been strongly required. Laser welding with micro-beam and high-speed scanning is a promising solution in micro-welding, because it has high-potential advantages in welding heat sensitive components with precise control of heat input and minimal thermal distortion. Approach: In this study, the characteristics of laser micro-welding of thin stainless steel sheets by using a single-mode CW fiber laser with high-speed scanning system were experimentally investigated. Results: It was clarified that the welding bead width and depth increased with increasing the scanning velocity under a constant energy density condition and high efficient welding was expected by using high-speed laser scanning with Galvano scanner. The utilization of shielding gas is very effective to obtain smooth fusion bead and the combination of micro beam spot and high-speed laser scanning made it possible to obtain good overlap welding of ultra-thin stainless steel sheets. Conclusion: A faster and high quality welding could be achieved by using a single-mode fiber laser with micro-beam and high-speed scanning.

http://www.thescipub.com/abstract/10.3844/ajeassp.2011.306.312 2011/08/18 - 08:29

Problem statement: The heart is the first organ and most importantly to form in the body, where is found the most powerful generator of electromagnetic energy in the human body. Electrophysiology is the best method used to diagnose human heart problem. Knowledge of the electrical potentials in human heart is a quantum leap in the science of the human heart. Recently, there has been a growing interest in studying the human ECG. However, is unfortunately a very complicated issue which requires a relatively good understanding of everything that has been said about the heart. Focus on the review of physical, electromagnetic basis of human heart's biopotentials and understanding the basic equations of cardiac electrophysiology that represents the basis to all clinicians whether in postnatal (pediatric or adult) or prenatal (foetal) Medicine. Approach: Mathematical method used for derivation of the essential equations of human heart electrical potentials, this equation will develop the principle sciences of human heart, the equation also outlier finding of the electromagnetic base of human electrophysiology. Results: Heart is important electrical generator in human body. The voltage and current which was generated in human heart represent the basis of heart biosciences. The electromagnetic energy of the heart not only envelops every cell of the human body, but also extends out in all directions in the space around human body. Conclusion: The proposed technique for electrophysiology and potentials on human ECG was useful and the results may contribute to the references for later studies.

http://www.thescipub.com/abstract/10.3844/ajeassp.2011.313.319 2011/08/18 - 08:29

Problem statement: Accounting for uncertainties that are present in geometric and material data of reinforced concrete buildings is performed in this study within the context of performance based seismic engineering design. Approach: Reliability of the expected performance state is assessed by using various methodologies based on finite element nonlinear static pushover analysis and specialized reliability software package. Reliability approaches that were considered included full coupling with an external finite element code and surface response based methods in conjunction with either first order reliability method or importance sampling method. Various types of probability distribution functions that model parameters uncertainties were introduced. Results: The probability of failure according to the used reliability analysis method and to the selected distribution of probabilities was obtained. Convergence analysis of the importance sampling method was performed. The required duration of analysis as function of the used reliability method was evaluated. Conclusion/Recommendations: It was found that reliability results are sensitive to the used reliability analysis method and to the selected distribution of probabilities. Durations of analysis for coupling methods were found to be higher than those associated to surface response based methods; one should however include time needed to derive these lasts. For the reinforced concrete building considered in this study, it was found that significant variations exist between all the considered reliability methodologies. The full coupled importance sampling method is recommended, but the first order reliability method applied on a surface response model can be used with good accuracy. Finally, the distributions of probabilities should be carefully identified since giving the mean and the standard deviation were found to be insufficient.

http://www.thescipub.com/abstract/10.3844/ajeassp.2011.324.332 2011/08/18 - 08:29

Problem statement: In this research, we addressed the problem of minimizing the earliness-tardiness penalties and manufacturing costs of a single machine with a stochastic controllable processing and tooling cost. Approach: We developed a mathematical non-linear integer programming model and its linearised version to find the optimal solution. We introduced a new genome representation in single machine scheduling literature that evolved by a genetic algorithm to solve the problem. The genome representation includes two genes per job, one represents the job starting time and other corresponds to the job processing time. The algorithms were compared based on the solution quality, CPU time and memory consumption in bytes on a set of randomly generated test problems. Results: The results showed that developed algorithms could define the global optimal solution of most scheduling problems with n ¡Ü 20 jobs. For larger n, the developed genetic algorithm outperforms the math models in terms of solution quality and less CPU seconds while consumes moderate memory kilobytes of 3295 compared with 5058 and 1685 of linear and nonlinear models on the average. Conclusion: The GA's average performance achieves 6.013 related to the lower bound of math linear program whereas nonlinear model achieves an average of 1.034. The GA's performance increases by increasing n compared with other techniques. We hope to expand the developed algorithms for different configurations as parallel and job shops.

http://www.thescipub.com/abstract/10.3844/ajeassp.2011.333.341 2011/08/18 - 08:29

Problem statement: Main purpose of this study was to investigation toothed gear loading problems using the Finite Element Method. Approach: We used Niemann's equations to compare maximum bending stress which was developed at critical gear-tooth flank point during gear meshing, applied for three distinct spur-gear sizes, each having different teeth number, module and power rating. Results: The results emerging after the application of Niemann's equations were compared to the results derived by application of the Finite Element Method (FEM) for the same gear-loading input data. Results are quite satisfactory, since von Mises' equivalent stresses calculated with FEM are of the same order with the results of classical analytical method. Conclusion: Judging from the emerging results, deviation of the two methods, analytical (Niemann's equations) and computational (FEM), referring to maximum bending stress is fairly slight, independently of the applied geometrical and loading data of each gear.

http://www.thescipub.com/abstract/10.3844/ajeassp.2011.342.346 2011/08/18 - 08:29

Problem statement: The aim of this study is enhance a better understanding of how coastal construction requirements are different from those for inland construction. As we may not be aware that the coastal construction is different from inland construction. Building in a coastal environment is different from building in an inland area. In general, buildings in coastal areas must be designed and built to withstand higher loads due to its more extreme conditions. Nowadays, the issue of global warming, uncertainty of global weather and the climate change effect indirectly creating the coastal area with much more expose to extreme condition. Formulate initial guidelines with certain degree of details how coastal construction requirements are different from those for inland construction. Due to the exposure to higher loads and extreme conditions, these structures in coastal areas will cost more to design, construct, maintain, repair and insure. Approach: Proper and right usage of building materials including electrical and mechanical equipments, are crucial in order to minimize damage. Nowadays, the issue of global warming, uncertainty of global weather and the climate change effect indirectly creating the coastal area with much more expose to extreme condition. Feedback has been gathered from the government local engineers who are doing the management of the Government's local buildings located along the coastal area of Peninsular Malaysia. Data findings through research method, discussion with the suppliers and discussion with coastal buildings maintenance crews also has been done. Results: The research finding discus the specific characteristics that makes for successful coastal buildings focusing in tropical region. Conclusion: We must accept on the idea of building in coastal areas will require more maintenance and upkeep. By having proper coastal building guideline may create more positive awareness in constructing better management coastal buildings and can save time and money to maintain the said structures.

http://www.thescipub.com/abstract/10.3844/ajeassp.2011.347.354 2011/08/18 - 08:29

Problem statement: Mosses have been widely used as bioindicator especially to study the levels of trace metals pollutants in the surrounding ambient air because of their high efficiency to accumulate heavy metals contamination. There has been increasing demand to get a suitable analytical tools to determine the chemical contents of moss samples in this type of media. Therefore, this study was conducted with the aims to get one of the best analytical methods for the analysis of moss samples. Approach: Despite the various spectroscopic techniques that normally used to analyzed heavy metals in moss, each of these techniques has its advantages and disadvantages which been summarized elsewhere. We try not to use any chemical to decompose the samples where the samples were analyzed directly in its solid form by Energy Dispersive X-Ray Fluoresence Spectrometer, EDXRF technique. The EDXRF technique optimized for its main analytical parameters. Calibration procedure was made based on the in-house standard samples. The reliability of the optimized analytical procedure was established by analyzing two certified reference materials, Pine Needle, NIST 1575 and Lichen, IAEA-336. Results: The results showed that the metals could be analyzed with percent recoveries range within 84-102% for Pine Needle and 92-125% for Lichen. The possible factors influencing the percent recoveries of the elements were discussed in details. Conclusion: On overall, it is strongly suggest that the applied EDXRF method is adequate enough to analysis the heavy metal contents in moss samples even at very small concentration with high accuracy and precisely.

http://www.thescipub.com/abstract/10.3844/ajeassp.2011.355.362 2011/08/18 - 08:29

Problem statement: Freight transportation data was indispensable input to transportation planning. In Thailand, efforts had been put to collect freight movement data by conducting road side survey and commodity flow survey. The result of these surveys did not produce consistent volume of shipment due to limited sampling coverage and non-response. Nevertheless, freight distribution patterns, which were derived from these surveys, were favorably consistent with each other. Approach: The objective of this study was propose an approach to improving quality of the commodity flow survey data in terms of total shipment weight. Our scope of study is limited to consumer goods and food stuffs. Multiple imputation was performed to correct non-response. The shipment weight was again adjusted by taking into account of the probability of no shipment in a particular quarter. Results: Comparison between the adjusted weight and road side survey data showed that the discrepancies in total weight of significantly reduced. Conclusion: Total shipment weights of the CFS after the adjustments were compared to those of road side survey. Plausible result was obtained for the case of consumer goods, while that of food stuffs was still notably different.

http://www.thescipub.com/abstract/10.3844/ajeassp.2011.363.371 2011/08/18 - 08:29

Problem statement: Predicting customer's future orders has an essential role in planning appropriate strategy in a Supply Chain Management (SCM) implementation. Purpose of this study is to identify how predicting future orders can facilitate managing activities across companies. Approach: A case study conducted in four Iranian automotive organisations to understand the actual results of order prediction in managing organisational processes. Results: Results of case study highlighted that more than 86% of activities completed before actual orders were received in these organisations. Conclusion: The findings show the high level of order management in these organisations which are the results of accessing to the right and timely information. This study would give invaluable information to all researchers who investigate the impact of order prediction in fulfilling organisational activities.

http://www.thescipub.com/abstract/10.3844/ajeassp.2011.372.379 2011/08/18 - 08:29

Problem statement: This study presents an application of Indirect Adaptive Generalized
Predictive Control (IAGPC) of an incubator for newborn, in order to improve the performance of
temperature control. Approach: Analysis of physical phenomena of incubator was involved together
knowledge of the dynamic behavior. Incubator was identified by means of Recursive Least Square
(RLS) technique associated with a projection of the model parameters for robust system identification.
Results: Results showed that mathematical model of neonatal incubator predicted coincide with the
measured data. A comparative study was made between ON-OFF, PID and IAGPC control in order to
provide the performance of each strategy. Conclusion: Results had proved effectiveness of the IAGPC
as a control of incubator system.

http://www.thescipub.com/abstract/10.3844/ajeassp.2011.235.243 2011/08/14 - 18:59

Problem statement: The performance of bituminous sealants in the field is partly
controlled by properties and strength of the sealant-aggregate interface. The thermodynamic work of
adhesion represents energy required for reversible separation of the two materials at the interface. The
study of fracture includes the energy required for both reversible and irreversible processes during
separation. Excess of work of facture over work of adhesion represents the energy consumed by
irreversible processes in the specimen during loading and fracture. In addition, adhesion strength is
related to the properties of constitutive components. Approach: The objective of this study was to
measure or predict adhesion of hot-poured bituminous-based sealant to aggregates of different
chemical composition. In order to accomplish, the study of fracture and the thermodynamic work of
adhesion were estimated for 14 hot-poured bituminous-based sealants with two types of aggregate:
Limestone and quartzite. The work of adhesion for each sealant-aggregate system was calculated from
the contact angle measurements of system components at corresponding sealant installation
temperature. Results: In general, limestone showed better adhesion to hot-poured crack sealant than
quartzite. Interfacial parameters such as contact angles and surface tensions were successfully used to
differentiate between sealants. Conclusion/Recommendation: The findings were in agreement with
preliminary testing results of 14 sealants using a newly developed fixture in the direct-tension testing
machine. Provided the sealant has an appropriate viscosity to fill the crack, as the sealant surface
tension decreases, its adhesion strength increases.

http://www.thescipub.com/abstract/10.3844/ajeassp.2011.244.251 2011/08/14 - 18:59

Problem statement: Automating semi-automatic dynamic machines and complex systems,
where some functionalities are already automated but the machine doesn’t run fully in automatic
mode, represents another challenge to automating dynamic and manual complex systems. This study
deals with a special case of this general problem, where the system’s semi-automatic and automatic
functionalities run separately in a sequence with either automatic and/or semi-automatic functionality
running at any point of time, but not both. Approach: Petri-nets can successfully represent the
operations of both the semi-automated and fully-automated functionalities of such dynamic systems.
Three roles for the programmable logic controllers were suggested: (a) Ignoring the presence of the
semi-automatic part, (b) simulating the semi-automatic part and recognizing discrepancies and(c)
simulating the semi-automatic functionalities and supporting it, where the last choice was most costly
and most reliable. Results: This study presents a case study for a PVC mixing dynamic process to
illustrate the three suggested controller design possibilities, where a Petri net model and related ladder
logic program were developed to show these three controller design options. In this respect, the semiautomatic
functionality is an intermediate step between the two automated functionalities, within which
an important decision should be made to end the previous automatic step and to begin the next automatic
step. Conclusion/Recommendations: The automation method that was introduced in this study is
applicable to a large number of machines within industrial and mechanical systems that were built using
older semi-automatic control systems. Various decision analyses {DA1, DA2, DA3} were shown to
produce basic choices for such types of applications. Petri-nets and ladder logic in this respect can
successfully represent the operations of both the semi-automated and fully-automated functionalities,
where a Petri net model and the consequent ladder logic program, used to program the utilized
programmable logic controller, are developed to show three possible controller designs, where the choice
between three designs depend on the designers objective of cost, reliability and fault tolerance.

http://www.thescipub.com/abstract/10.3844/ajeassp.2011.252.264 2011/08/14 - 18:59