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The variance of the brightness of pulp sent to the paper mill during the changing period of dry pulp grades affects the chemical control in the paper mill. This research aims to determine the mixing formula of pulp with different brightness from the EOP and D1 stages to handle this variation issue. This research uses response surface design with Central Composite Design type, regression technique and optimization technique to find the optimal setting of the mixing formula for each of the seven brightness levels to obtain the target brightness of 86% and the pH of 5.25. The mixing formulas are determined by the pulp mixing percentage and the sulfuric acid consumption. The experimental results reveal that when using higher EOP mixing ratio, the brightness decreases and the pH increases. Regarding the effect of the sulfuric acid, increasing the sulfuric acid makes the brightness and the pH decrease. After implementing the optimal formula in the production line, the mean of pulp brightness is closer to the target compared with the brightness before improvement and the brightness variation decreases without affecting the quality of other pulp grades, average of brightness decreased from 87.4% to 86.3% and standard deviation of brightness decreased from 1.09 to 0.46.

The study was undertaken to assess the heat released of briquettes produced from waste paper and groundnut shell admixture in five mixing ratios (90:10; 80:20; 70:30; 60:40; and 50:50). The briquettes were prepared on an existing motorized briquetting machine. The suitability of briquetted fuel as domestic fuel was studied in terms of flame propagation, afterglow, calorific value, and utilized heat, after sun drying the prepared briquettes for nineteen (19) days. The results of propagation rate and afterglow obtained for all the six compositions are satisfactory they range between 0.13 to 0.14 and 365 to 380 respectively. These energy values obtained for the whole samples are sufficient enough to produce heat required for household cooking and small scale industrial cottage applications. Finally it was observed that composition variation affects the properties of the briquettes.

The objective of this research is to study the level of the important factors that can decrease total cost of pulp production. First of all, experts and experienced users identify the factors that affect the total production cost by applying the principle of 4M 1E cause and effect diagram. Then the primary factors were chosen based on 80% of their significance and tested by hypothesis for two population means. It was found that at the 95% confidence level the significant factors that have effects on the total production cost are amount of Effective alkali in white liquor and Kappa number. However, the proportion of easy delignification according to Eucalyptus species is considered as a significant factor based on various studies. Box-Behnken experiment is designed with respect to 3 mentioned factors and 3 levels of each factor. The response surface method (RSM) is employed to determine the non-linear relation between the total cost as the response and the proportion of easy delignification, amount of Effective alkali in white liquor and Kappa number. To minimize the total cost, the optimal values of each factor are 75% of easy delignification, 112 grams per liter of Effective alkali in white liquor and 13.5 of kappa number. Under this optimal condition, the average total cost per ton of Eucalyptus is 13,393.91 Baht which is significantly less than the total cost of 15,517.06 Baht per ton before improvement.

This paper presents the methodology of the de-soldering process for rework of disk drive Head Stack Assembly (HSA) units. The auto wire feeder is a machine that generates Tin (Sn) on the product. This machine was determined to be one of the major sources of excess Sn on the HSA. The defect rate due to excess Sn is more than 30%, which leads to increased processing time and cost to perform additional cleaning steps. From process analysis, the major causes of excess Sn are as follows: 1) The machine cannot cut the wire all the way into the flux core area; 2) The sizes and types of soldering irons are not appropriate for the unit parts; and, 3) There are variations introduced into the de-soldering process by the workforce. This paper proposes a methodology to address all three of these causes. First, the auto wire feeder machine in the de-solder process will be adjusted in order to cut wires into flux core. Second, the types of equipment and material used in de-soldering will be optimized. Finally, a new standard method for operators, which can be controlled more easily, will be developed in order to reduce defects due to workforce related variation. After these process controls and machine adjustments were implemented, the overall Sn related problems were significantly improved. Sn contamination was reduced by 41% and cycle time was reduced by an average of 15 seconds.

Monitoring density changes during transportation of composite fillers is the principal reason for composite industries implementing the tapped density concept. Till date, very sparse literature information exists on tapped density optimisation for orange peel particles (OPPs). A unique application of grey relational analysis (GRA) in the optimisation of tapped process parameters for OPPs is contributed in this paper. Experimental results on the principal process parameters indicate G1H1I2J3 as the best experimental run, which translates to 257.956 g and 78.076 cm3 as well as 254.939 g and 72.94 cm3 for masses and volumes of the 0.425 and 0.600 mm OPPs, respectively. In addition, Taguchi method was applied to arrive at an optimal parametric setting of G2H2I1J1 for comparative purposes which translate to 257.723 g and 75.031 cm3 for mass and volume of the 0.425 OPPs, as well as 254.952 g and 77.982 cm3 for the mass and volume of 0.600 mm OPPs. By comparison, the GRA values produced positive percentage improvement over other optimal values. The unique contribution of this paper are principally the (i) application of GRA in a novel manner, incorporating harmonic mean in factor-level determination and computation of S/N responses; (ii) development of new indices of tapped density; and (iii) introduction of economic factors in tapped density computations, incorporating inflation and interest factors. The practical utility of the demonstrated approach lies in reducing the uncertainties about density measurements in the transportation of green fillers for use as composite reinforcements.

This paper presents the continuous sampling plan CSP-100 that was developed from the continuous sampling plans CSP-1, CSP-4 and CSP-C. The objective of this paper is to apply the continuous sampling plan for the new CSP-100 plan proving a reduction in the delivery inspection time compared to the single lot sampling plan (SSP) while maintaining the same or greater quality conformance. This CSP-100 was studied in Hard Disc Drive manufacturing. The parameters used in the CSP-100 plan are as follows; i (the number of consecutive conforming units), f (the sampling frequency of partial number in 100% inspected units) and c (the acceptance number). CSP-100 computes four performance measures, Average Fraction Inspected (AFI), Average Outgoing Quality (AOQ), Lot Acceptance Rate (LAR) and Defective Parts Per Million (DPPM). The advantage of this CSP-100 plan is not only to reduce the inspection time but also prove higher productivity numbers when compared with SSP. The verified results of using the CSP-100 plan proved a reduced inspection time of 6,722,702 minutes or 15% compared to SSP. CSP-100 also eliminates the work stations and transportation processes due to the inspection area and inspectors are no longer required. The Function Out of Box Audit (FOBA) is introduced to monitor the CSP-100 performance. The FOBA audit results confirm that the CSP-100 maintains the same good quality level as the SSP. The excellent results of implementing the CSP-100 show a reduction in the inspection cost by 3,693,730.04 baht or 60.40% compared to SSP, as well as the additional cost savings by no longer needing to purchase a new tester; a savings of ~44 million baht. The CSP-100 plan also eliminates the issue of delayed delivery that is part of the SSP process. Moreover it is a better choice in inspecting the continuous quality process in Hard Disc Drive manufacturing.

Speed limits in accordance with environment and road functions have been used as a fundamental tool for speed management and road safety. This paper presents literatures review of speed limits measure and results from the study on speed limits problem and driver attitude toward the speed limit and speed control measure. Area of study is on the arterial road where the Mittaprab Highway passed through Khon Kaen City. The study found that improper designation of road functions is the main cause of complexity and difficulty on safety management. It suggests more researches on speed limit setting methods to accommodate the road conditions of the country. In order to increase effectiveness of speed limits measure, this paper suggests transportation-related authorities to classify this area to be the urban arterial road, to set proper speed limits, and to modify the road environment in accordance with its function. More measures to enhance speed limit effectiveness and to reduce accident are included automatic speed control devices, speed limits warning signs, and advertisement signs to use the bypass route. These could enhance the effective speed management program.

The objective of this research is a reduction of an adhesive stain defect in flexible printed circuit board in hot pressing process, the electronic factory. The manufacturing have been processing by sheet type of products with ninety-six pieces of flexible printed circuit boards. Causes of the problem include the before and internal hot pressing process. In process beginning times, the most right row of products between the cooling plate and the hot pressing machine has temperature 71.2◦C that is higher than glass transition temperature (Tg) 60◦C. Those products’ temperature lead to evaporate a polyimide adhesive before hot pressing process beginning. The internal hot pressing process include the preheat times and the pressure time. In the preheat time the problem is a gap between lower and upper plate, was under specification (Under 1 mm) and leaded to adhesive polyimide stain. In the actuality this time requires temperature and low pressure that mean a gap within 1 – 2 mm (between lower and upper plate). In pressure times the hot pressing plate surface is not flat and products are pressed by insufficient force that it lead to generate an adhesive stain on flexible printed circuit boards. That force is measured by the pre-scale paper and a result, RGB color, is provided. And then color density (From standard color sample) and RGB color (From pre-scale paper) is found out the relation by Photoshop program and multiple regression theory using. The formula is applied to compare with defect so as to find out the suitable color density (Defects reducing). The solving solutions is provided including the gap reduced adjustment between cooling plate and hot pressing machine before hot pressing process, the plate adjustment within specification in the preheat time and the pressing plate polishing in the pressure time. Results of study and solving are provide defect reduction from 24.4 percentage to 7.2 percentage of total study product.

This paper presents a reconfiguration technique for distribution system with distributed generation (DG) using Firefly algorithm (FA). The objective is to minimize total power losses of the system. In this paper, the technique is tested on the IEEE 33-bus radial distribution system. The result shows that the method can be applied to practical system using switching for reconfiguration. In comparison to the other techniques, it is also capable to find good solution. Therefore, it can be used as an alternative to the other reconfiguration techniques.

A two-stage data envelopment analysis (DEA) which uses mathematical linear programming techniques is applied to evaluate the efficiency of a system composed of two relational sub-processes, by which the outputs from the first sub-process (as the intermediate outputs of the system) are the inputs for the second sub-process. The relative efficiencies of the system and its sub-processes can be measured by applying the two-stage DEA. According to the literature review on the supply chain management, this technique can be used as a tool for evaluating the efficiency of the supply chain composed of two relational sub-processes. The technique can help to determine the inefficient sub-processes. Once the inefficient sub-process was improved its efficiency, it would result in better aggregate efficiency of the supply chain. This paper aims to present a procedure for evaluating the efficiency of the supply chain by using the two-stage DEA, under the assumption of constant returns to scale, with an example of internal supply chain efficiency measurement of insurance companies by applying the two-stage DEA for illustration. Moreover, in this paper the authors also present some observations on the application of this technique.

This paper presents an efficient technique for improving the efficiency of Thai error correction system by using memetic algorithm. In this paper, the token passing algorithm is used for constructing word graph and the language model is used checking the correct sentence. The correction process starts with word graph construction from token passing algorithm, then the correct sentence are searched by memetic algorithm with the best fitness function from language model. For a long sentence from the token passing algorithm, a search space is very huge which can be resolved by using memetic algorithm. The memetic algorithm is used for searching the correct sentence in order to reduce the analysis time. The performance of the proposed method are evaluated and compared to the full search and genetic algorithm. From the experimental results show that the proposed method performs very well and yields better performance more than the compared method. The proposed method can search the best sentence accurately and quickly.

The objective of this research is a reduction of an adhesive stain defect in flexible printed circuit board in hot pressing process, the electronic factory. The manufacturing have been processing by sheet type of products with ninety-six pieces of flexible printed circuit boards. Causes of the problem include the before and internal hot pressing process. In process beginning times, the most right row of products between the cooling plate and the hot pressing machine has temperature 71.2◦C that is higher than glass transition temperature (Tg) 60◦C. Those products’ temperature lead to evaporate a polyimide adhesive before hot pressing process beginning. The internal hot pressing process include the preheat times and the pressure time. In the preheat time the problem is a gap between lower and upper plate, was under specification(Under 1 mm) and leaded to adhesive polyimide stain. In the actuality this time requires temperature and low pressure that mean a gap within 1 – 2 mm (between lower and upper plate). In pressure times the hot pressing plate surface is not flat and products are pressed by insufficient force that it lead to generate an adhesive stain on flexible printed circuit boards. That force is measured by the pre-scale paper and a result, RGB color, is provided. And then color density (From standard color sample) and RGB color (From pre-scale paper) is found out the relation by Photoshop program and multiple regression theory using. The formula is applied to compare with defect so as to find out the suitable color density (Defects reducing). The solving solutions is provided including the gap reduced adjustment between cooling plate and hot pressing machine before hot pressing process, the plate adjustment within specification in the preheat time and the pressing plate polishing in the pressure time. Results of study and solving are provide defect reduction from 24.4 percentage to 7.2 percentage of total study product.

In the Impedance Matching (IM) condition of Wireless Power Transfer (WPT), series resonant and strong coupling structures have been widely studied which operate at an optimal parameter, a resistive load, and the high resonant frequency of greater than 1 MHz. However, i) The optimal parameter (particular value) limits the design, ii) the common loads are complex, iii) The high frequency RF sources are usually inefficient. This paper presents a modified parallel resonant structure that can operate at a low frequency of 15 kHz without an optimal parameter under the IM condition with a complex load, and the calculated efficiency is equal to 71.2 % at 5-cm transfer distance.

This paper proposes the method, called the Filter Partitioning Machine Learning Classifier (FPMLC). It can enhance an accuracy of indoor positioning based on fingerprinting by using machine learning algorithms and prominent access points (APs). FPMLC selects limited information of groups of the signal strength and combines a clustering task and a classification task. There are three processes in FPMLC, i.e. feature selection to choose prominent APs, clustering to determine approximated positions, and classification to determine fine positions. This work demonstrates the procedure of FPMLC creation. The results of FPMLC are compared with those of a primitive method by using real measured data. FPMLC is compared with well-known machine learning classifiers, i.e. Decision Tree, Naive Bayes, and Artificial Neural Networks. The performance comparison is done in terms of accuracy and error distance between classified positions and actual positions. The appropriate number of selected prominent APs and the number of clusters, are assigned in the clustering process. The result of this study shows that FPMLC can increase performance for indoor positioning of all classifiers. In addition, FPMLC is the most optimized model while having Decision Tree as its classifier.

The assessment of sustainability performance has become a topic widely discussed by business practitioners. The complexity of this issue is highlighted by the incorporation of a large number of criteria. Several methods under the context of Multiple Criteria Decision Analysis (MCDA) have been employed to facilitate the aggregation of various criteria and to provide a guideline for decision making. As most MCDA methods assume that each criterion plays a role equal to its weight, this paper investigates the weight of each criterion in evaluation of corporate sustainability by focusing on the sugar industry in order to respond to the lack of MCDA and sustainability studies in this sector. The weighting is analysed by means of the relative importance based upon interviews and the direct rating technique. Statistical analysis is also conducted. The results from this empirical research indicate priorities of sustainability criteria and demonstrate the diversity of concerns within the industry when deciding on sustainability policies and strategies. This encourages practitioners to incorporate uncertain weights of sustainability criteria into decision making. Possible reasons for variations or changes in weights have been also discussed, and this enables practitioners to perform a sensitivity analysis in a more realistic way.

This paper addresses a problem of the two-stage flexible flow shop with reentrant and blocking constraints in Hard Disk Drive Manufacturing. This problem can be formulated as a deterministic FFS|stage=2,rcrc, block|Cmax problem. In this study, adaptive Hybrid Particle Swarm Optimization with Cauchy distribution (HPSO) was developed to solve the problem. The objective of this research is to find the sequences in order to minimize the makespan. To show their performances, computational experiments were performed on a number of test problems and the results are reported. Experimental results show that the proposed algorithms give better solutions than the classical Particle Swarm Optimization (PSO) for all test problems. Additionally, the relative improvement (RI) of the makespan solutions obtained by the proposed algorithms with respect to those of the current practice is performed in order to measure the quality of the makespan solutions generated by the proposed algorithms. The RI results show that the HPSO algorithm can improve the makespan solution by averages of 14.78%.

Soil salinity causes corrosion of engineering structures worldwide. The main cause of soil salinization is capillary rise of saline groundwater. Soil salinity can be mitigated once the capillary rise of saline groundwater in soils is understood. The objective of this paper is to present experimental results of capillary rising rates of different salt concentration waters in three sandy soils. Each sample comprised of a soil column 300-mm height and 50-mm in diameter steeped in a 25-mm deep saline water pool for a time period to allow for the capillary action to develop. The salinity strength varied from fresh water, EC = 2 dS/m, to medium saline (50, 100, and 150 dS/m), and to high saline water (200 dS/m). It was found that the highest rate of capillary rise occurred in medium saline waters, while the lowest is the fresh water. The very saline water has lower rate than the medium ones but higher than fresh water.

In manufacturing process where efficiency is crucial in order to remain competitive, flowshop is a common configuration in which machines are arranged in series and products are produced through the stages one by one. In certain production processes, the machines are frequently configured in the way that each production stage may contain multiple processing units in parallel or hybrid. Moreover, along with precedent conditions, the sequence dependent setup times may exist. Finally, in case there is no buffer, a machine is said to be blocked if the next stage to handle its output is being occupied. Such NP-Hard problem, referred as Blocking Hybrid Flowshop Scheduling Problem with Sequence Dependent Setup/Changeover Times, is usually not possible to find the best exact solution to satisfy optimization objectives such as minimization of the overall production time. Thus, it is usually solved by approximate algorithms such as metaheuristics. In this paper, we investigate comparatively the effectiveness of the two approaches: a Genetic Algorithm (GA) and an Artificial Bee Colony (ABC) algorithm. GA is inspired by the process of natural selection. ABC, in the same manner, resembles the way types of bees perform specific functions and work collectively to find their foods by means of division of labor. Additionally, we apply an algorithm to improve the GA and ABC algorithms so that they can take advantage of parallel processing resources of modern multiple core processors while eliminate the need for screening the optimal parameters of both algorithms in advance.

In this paper, we survey the role of mathematics in electrical network connections. We discuss the behavior of current flows, voltages and impedances mainly for series-parallel networks. In both one-port and multiport electrical networks, the currents through these networks are governed by Maxwell’s power principle. The joint impedances of the networks, given in terms of series sum and parallel sum, satisfy the series-parallel inequality. An abstract idea can be formulated in functional analysis aspect in which any network connection is viewed to be a binary operation for positive operators satisfying certain algebraic, order and topological properties.

In this paper, the influence of fly ash fineness on water requirement and shrinkage of blended cement mortar was studied. The results indicate that the water requirement and shrinkage characteristic of the blended cement mortar are dependent on fly ash fineness and replacement level. The use of coarse fly ash slightly reduces the water requirement but greatly reduced the drying and the autogenous shrinkage of the blended cement mortars and the reduction is more with an increase in the fly ash replacement level. The finer fly ashes further reduce the water requirement, but increase the drying and the autogenous shrinkages as compared with coarser fly ash. The incorporation of superplasticizer drastically reduces the water requirement, but the effect on the drying and autogenous shrinkages of the normal Portland cement mortar is small. However, for the fly ash mortar, the use of superplasticizer results in a decrease in drying shrinkage and in a substantial increase in the autogenous shrinkage particularly for the fine fly ash at a high replacement level.

Because of nonlinear strain distributions caused either by abrupt changes in geometry or in loading in deep beam, the approach for conventional beams is not applicable. Consequently, strut-and-tie model (STM) has been applied as the most rational and simple method for strength prediction and design of reinforced concrete deep beams. A deep beam is idealized by the STM as a truss-like structure consisting of diagonal concrete struts and tension ties. There have been numerous works proposing the STMs for deep beams. However, uncertainty and complexity in shear strength computations of deep beams can be found in some STMs. Therefore, improvement of methods for predicting the shear strengths of deep beams are still needed. By means of a large experimental database of 406 deep beam test results covering a wide range of influencing parameters, several shapes and geometry of STM and six state-of-the-art formulation of the efficiency factors found in the design codes and literature, the new STMs for predicting the shear strength of simply supported reinforced concrete deep beams using multiple linear regression analysis is proposed in this paper. Furthermore, the regression diagnostics and the validation process are included in this study. Finally, two numerical examples are also provided for illustration.

Lightning striking on a transmission tower induces high ground potential rise and high voltage at tower arms in which potential is normally at ground level, and subsequently causes overvoltage across an insulator string. If this overvoltage is higher than the withstanding voltage of the insulator string according to the v-t (voltage-time) curve, back flashover phenomena will occur and this event may cause outage. The main objective of this paper is to study the factors influencing the back flashover phenomena. The computer program PSCAD/EMTDC (Power System Computer Aided Design/Electromagnetic Transients including DC) is used to simulate lightning striking on a transmission tower 115kV. Lightning current, transmission towers, ground resistance, insulator strings and back flashover phenomena are modeled. Main simulations are lightning striking on different towers, different soil resistivity, different lightning current magnitudes and wave shapes, different locations, and different phase angles of source voltage. Simulation results show that the higher tower encounters higher induced voltage. A back flashover occurs at the top tower arm easier than at the middle and lower arms. The higher soil resistivity induces higher voltage. The larger lightning current magnitude impacts on higher induced voltage. The longer rise time of lightning current generates lower induced voltage. Lightning strikes directly on tower generate higher voltage than that of striking on overhead ground wires.

This paper presents the concept of a speed estimation of sensorless control for asymmetrical parameter type two-phase induction motor drive, by using the adaptive observer system. The motor speed is estimated on the rotor-flux reference frame to simplicity for application. The design guideline of the gain of speed estimate system for a motor has speed change. The experimental results for all test conditions show that the responses of current, torque and speed are stable for the entire operating region.

Ancient statues are cultural heritages that should be preserved and maintained. Nevertheless, such invaluable statues may be targeted by vandalism or burglary. In order to guard these statues by using image processing, this research aims to develop a technique for detecting images of ancient statues with missing parts using digital image processing. This paper proposed the effective feature extraction method for detecting images of damaged statues or statues with missing parts based on the Histogram Oriented Gradient (HOG) technique, a popular method for object detection. Unlike the original HOG technique, the proposed method has improved the area scanning strategy that effectively extracts important features of statues. Results obtained from the proposed method were compared with those of the HOG method. The tested image dataset composed of 500 images of perfect statues and 500 images of statues with missing parts. The experimental results show that the proposed method yields 99.88% accuracy while the original HOG method gives the accuracy of only 84.86%.

This study was aimed to increase the impact resistance of circular tubes reinforced by fiber reinforced plastic (FRP).The tube made of aluminum 6063-T5 with the D/t ratio of 25.40, 29.63, and 42.33. Outside surface of aluminum tube was reinforced by wrapping fiberglass/polyester. The fiber orientation angle were [0]3 , [45]3 , [90]3 , [0/902 ], [45/-452 ], and [90/02 ]. Then, they were tested under impact with cross head of 45 kg and speed of 6.26 m/s in axial direction. The result revealed that the impact resistance of the hybrid tube and aluminum tube trend to increase as the D/t ratio increases and The hybrid tube with wrapped angle of [0/902 ] was maximum mean load and higher than aluminum tube by 50.02, 45.14, and 52.03 % at D/t = 25.40, 29.63, and 42.33 receptively. Failure mode and crush behavior of hybrid tube were also presented and disused in this paper.

Social media sites have experienced an explosion in both the number of users and the amount of user-contributed content in recent years. There is the need for the solution for information overload in social media. In this paper, we focus on solving the problem of finding relevant Twitter users to follow and selecting only popular tweets to post, we have collected information about Twitter users, particularly the number of influential users who are followers, the number of general followers, and the number of tweets that are frequently retweeted. Then we used such statistics information to compute the user rankings. In addition, we also created a Twitter account to automatically post only tweets that have been retweeted many times. Based on the survey result and using the Spearman’s rank correlation coefficient, the recommended Twitter users suggested by the system have proven to be popular and pertinent, and the rank order by the proposed system has a statistical significant degree of similarity with the user survey result.

Currently the amount of web data has increased excessively. Its metadata is widely used in order to fully exploit web information resources. This causes the need for Semantic Web technology to quickly analyze such big data. Resource Description Framework (RDF) is a standard for describing web resources. In this paper, we propose a method to exploit a NoSQL database, specifically MongoDB, to store and query RDF data. We choose MongoDB to represent a NoSQL database because it is one of the most popular high-performance NoSQL databases. We evaluate the proposed design and implementation by using the Berlin SPARQL Benchmark, which is one of the most widely accepted benchmarks for comparing the performance of RDF storage systems. We compare three database systems, which are Apache Jena TDB (native RDF store), MySQL (relational database), and our proposed system with MongoDB (NoSQL database). Based on the experimental results analysis, our proposed system outperforms other database systems for most queries when the data set size is small. However, for a larger data set, MongoDB performs well for queries with simple operators while MySQL offers an efficient solution for complex queries. The result of this work can provide some guideline for choosing an appropriate RDF database system and applying a NoSQL database in storing and querying RDF data.

This paper proposed a nonlinear finite element model to investigate mechanism and behavior of the concrete columns confined with metal sheet. Three dimensional modeling was chosen. Concrete was modeled using the Drucker-Prager yield criterion and a softening function, whereas the Von-Mises yield criterion was chosen for metal sheet. Between both materials, a set of interface elements was inserted to represent layers of the bonding material. The results showed that the finite element model could model the behaviors that were observed from the laboratory experiments, and could capture the mechanisms that were not noticed in the laboratory experiment as well.

The main objective of this paper is to discuss alternative approaches to convert a propositional logic problem into a 0-1 integer program. The substitution method proposed by Williams and CNF method is used for modeling and representation of logical inference problem. The similarity between the two fields viz. optimization problems or mathematical programming and deductive logic are shown.

This research is purposed to study crashworthiness behavior of fiberglass tube subjected axial compression. The specimens are made of fiberglass and hand lay-up in different ply angles which are; specimen A ply angle is [(0/90)/(0/90)/(0/90)] specimen B ply angle is [(45/-45)/(45/-45)/(45/-45)] and specimen C ply angle is [(45/-45)/(0/90)/(45/-45)]. The tube has 50 mm outside diameter, 2 mm wall thickness and 100 mm length. Quasi-static test is done by ESH Universal Testing Machine with 10 mm/min of crushing speed. Impact test is done by Vertical Impact Testing Machine with the impact speed of 7 m/s. The result showed that specimen A gives highest specific energy absorption due to the vertical fiber orientation. In addition, the collapse mode and response of specimens to impact are also discussed in the paper.

This paper presents the double input converters for different voltage input sources with isolated charger coils. This research aims to increase the performance of the battery charger circuit. In the circuit, there are the different voltage levels of input source. The operating modes of the switch in the circuit use the microcontroller to control the battery charge and to control discharge mode automatically when the input voltage sources are lost from the system. The experimental result of this research shows better performance for charging at any time period of the switch, while the voltage input sources work together. Therefore, this research can use and develop to battery charger for present or future.

To proposed a new adaptive intelligent system for a robot work cell that can visually track and intercept an invariant stationary HGA feature undergoing arbitrary orientation anywhere along its predicted trajectory within the robot’s workspace is presented in this paper. A combination of the seven invariant moment technique, image feature technique and the MADALINE network are used for identifying the stationary HGA at any rotation angle without overlapping and generating the predicted robot trajectory respectively. An invariant moment that has system for a scale, translation and orientation are calculated for each significant region in the input images. Inertial ellipse is determining for angle rotation that compare against to the accepted orientation that required. The result shown that, the relationship between the visual feedback image data and the control command for changing the axis motion shows deviation of robot placing less than 2% by the MADALINE network for intercepting stationary HGA at any rotation angle. The location and image features of these HGAs need not be preprogrammed, marked and known before, and any change in a task is possible without changing the robot program. Finally, this novel method can improve the hard disk drive (HDD) assembly process productivity.

For environmental reason, new binders that can be used as Portland cement replacement materials are being needed. Recently, alkali-activated binders (AAB) and geopolymer have found increasing interest. As several research reports have showed that the two new binders are likely to have high potential to be developed and become an alternative to OPC. However, confusion in the classification of both binders is still there. This paper reviews knowledge about AAB and geopolymer including historical background, reaction mechanisms and reaction products. The similarities and differences of both binders are discussed. The application to environmental engineering on hazardous waste management using stabilization/solidification is also described.

Research paper is the spray and engine performance investigation from preheated diesel and biodiesel oils at fuel temperature from 60 to 90 o C by comparing with non-preheated oil. In the experiment, there are fuel injection modeling and diesel engine testing, which is direct injection, 4 stroke and 4 cylinders. Results of fuel spray show that preheated diesel oil increase 4.7degree of spray angle and decrease 4.30 % of fuel injection pressure, as preheated bio-diesel oil increase 7.6degree of spray angle and decrease 13.90 % of fuel injection pressure to compare with non-preheated oil. As engine preformance testing results, preheated diesel oil increase 26.20% of thermal efficiency and decrease 4.30 % of BSFC, as preheated bio-diesel oil increase 30% of thermal efficiency and decrease 29.90 % of BSFC to compare with non-preheated oil.

This paper is aimed to investigate the properties of joint between AISI 4140 and AISI 1040 welded by friction welding. The specimens were prepared in round shape of 13 mm diameter and 100 mm long. They were welded by friction welding method under the following conditions; friction pressure of 183 MPa, friction time of 12 sec, upset pressure of 428 MPa, upset time of 7 sec. and rotational speed of 1400 rpm. The strength and hardness were tested on the welded area. The result showed finer grains. in the welded area. This is the result of friction pressure and upset pressure in the welding process. In addition, the observation result indicated some changes of Ferrite and Pearlite in welded zone. This phase change resulted in the increment of hardness in AISI 4140 at the contact area and adjacent. In part of AISI 1040, the portion of Pearlite and Ferrite are not significantly changed, therefore the value of hardness is almost constant.

This paper presents an investigation of airflow over a rugged mountain to find suitable locations for wind turbines. The investigation considers turbulent intensity and inflow angle in addition to wind speed. The area of interest is the mountain around the upper reservoir of Lamtakong Jolabha Vadhana Hydro Power Plant, Nakhon Ratchasima, Thailand. The Lamtakong Wind Turbine Power System is located near the reservoir. Due to the ruggedness of the site, according to the angle of slopes, the existing turbines may be experiencing airflow with high turbulent intensity and non-zero inflow angle. This study uses Computational Fluid Dynamics (CFD) and Wind Atlas Analysis and Application Program (WAsP) to simulate airflow. CFD is used in the final analysis to quantify turbulent intensity and inflow angle. The turbulence model is used, while the roughness height and roughness constant are tuned according to the ground cover. Detailed examinations of cases show that the highest wind speeds do not always occur at the mountain’s peaks. High turbulent intensity leads to the exclusion of locations on the lee side of the mountain, where it reaches 18%. The inflow angles are high on the upwind side of the mountain and can go up to 20 degrees. It is found that the slopes affect the inflow angles but they do not dictate the inflow angles. Finally, the results of the highest peak suggest that most suitable turbine spot is approximately 60 m downwind from the point of highest wind speed. The power density reduces from 515.3 W/m2 to 502.6 W/m2 at 60 m hub-height. Thus, to achieve a zero inflow angle, turbines may have a power output reduction but they will experience lower turbulence and uneven loading.

The objective of this paper is to design raw materials forecasting methods for material management process improvement of an outsourced ready-to-wear suit factory. In this research, we study demands of five types of frequently used raw materials and identify the most appropriate forecasting method providing the lowest Mean Absolute Percentage Error (MAPE). We found that Simple Exponential Smoothing method gives the most accurate result with smoothing parameters (α ) of 0.9439,0.6906,0.8656,0.9844and 0.8694 for SKU number EX102, RX101, HX101, IX103 and KX101, respectively. From the results, we found considering weekly demand yields more accurate forecasting results as compared to monthly demand. From our on-site experiment from October to December 2012 to identify the suitable time to adjust smoothing constant (α ), we found that the smoothing constant should be reviewed and adjusted every 4 weeks for SKU number RX101, HX101 and KX101, giving the MAPE results of 21.125, 13.170 and 18.952, respectively. For EX102 andIX103, the parameter should be reviewed every 8 weeks, giving the MAPE results of 7.538 and 8.897, respectively. Overall, the proposed model can reduce forecasting errors up to 45 percent as compared to the naïve method previously used in this factory.

Plagiarism is the act of taking another person's writing or idea without referring to the source of information. This is one of major problems in educational institutes. There is a number of plagiarism detection software available on the Internet. However, a few numbers of them works. Typically, they use a simple method for plagiarism detection e.g. string matching. The main weakness of this method is it cannot detect the plagiarism when the author replaces some words using synonyms. As such, this paper presents a new technique for a semantic-based plagiarism detection using Semantic Role Labeling (SRL) and term weighting. SRL is deployed in order to calculate the semantic-based similarity. The main different from the existing framework is terms in a sentence are weighted dynamically depending on their roles in the sentence e.g. subject, verb or object. This technique enhances the plagiarism detection mechanism more efficiently than existing system although positions of terms in a sentence are reordered. The experimental results show that the proposed method can detect the plagiarism document more effective than the existing methods, Anti-kobpae, Turnit-in and Traditional Semantic Role Labeling.

This paper aims to study appropriate ripeness of cultivated banana and time period for vacuum fry. Sliced bananas of thickness 1-2 mm were fried at temperature 130 ๐ C under vacuum condition. The samplings were done at 3 level of ripeness; 1) raw banana, 2) the first day of ripeness, 3) the second day of ripeness. In addition 5 levels of fried period were set; 6, 8, 10, 12, 14 min. The raw banana fried for 12 min shown the best result. The products have a crisp texture, appropriate hardness and toughness, standard moisture and color with the most acceptance by consumers.

This paper presents the COP prediction of an ejector refrigeration cycle combined with a vapour compression cycle for automotive air conditioning. Using computational fluid dynamics (CFD) technique, the performance of an ejector was analyzed in term of the entrainment ratio (Rm) and critical back pressure (CBP). The results from this study were compared with a previous study of combined ejector refrigeration system for automotive air conditioning application [1] which the entrainment ratio (Rm) were predicted from one-dimensional (1-D) equation. The performance of an ejector (Rm and CBP) from CFD and onedimensional method were analyzed and used as database for a mathematical modeling. In order to predict the COP of the combined system, a set of mathematical equations was developed using EES. The operating conditions are chosen accordingly as, intercooler temperature between 15 ๐ C and 25 ๐ C, condenser temperature equal to 35 ๐ C and evaporator temperature equal to 5 ๐ C. However, when generator temperatures are 80 ๐ C, 85 ๐ C and 90 ๐ C, the results showed average relative errors of the COP of an ejector refrigeration cycle (COPej), between CFD and 1-D are 44.64%, 50.47% and 59.68% respectively, and between CFD and 1-D NEW are 1.54%, 0.08% and 6.49% respectively.