Peeling of cassava tubers is one of the important steps in processing of cassava chips. The peeling is still manual, which has low capacity and is therefore insufficient for production needs. This project aims to design and fabricate a unit for cassava tuber knife peeling. The unit consists of a structure, power and transmission, and a knife peeling set. The study conditions were at 70, 80 and 90 rpm of knife rotating speed, with 3 different knife peeling types and 2 levels of spring stiffness of knife peeling (8.21 and. 17.19 N/m). The result shows that the most suitable conditions were 90 rpm of knife peeling speed, using a second knife peeling type and a spring stiffness of 17.19 N/m. The capacity was 10.43 seconds/tuber. The peeling efficiency was 90.3 and the percentage of flesh loss was 3.63

Nowadays, polymer materials have begun to play a greater role in human life. Epoxy resin is one of the most widely used polymer materials because of its relatively high mechanical properties and can be easily molded due to its presence in the liquid state before forming. Epoxy resin has various used in many sections of industries due to its easily forming and making. A wide variety of applications result in different load characteristics or dimension of parts made from epoxy resin. In the use of parts made from epoxy resin or containing epoxy resin, it is found that the parts are mostly damaged under the lower load designed. Due to the design of those complex parts, it does not take into account the crack occur on the part. If the parts are complex, the important factor to consider is the fracture toughness of the material used to make the parts. Therefore, this research aims to study the fracture toughness of epoxy resin under mode I loading, which simulates a variety of applications by changing the range of variables, loading rates, and thickness of the specimen. For calculating the fracture toughness of epoxy resin, it is calculated using the finite element method. From the result, it was found that the loading rate and thickness of the specimen clearly affected the fracture toughness and fracture behavior of the epoxy resin under mode I loading.

Recently, polymer foam is mostly used in sandwich structures, an application of panel in container floors and airplane’s wings, by using the advantage of high strength to weight ratio property. In several of application difference loads are absorbed, materials can failure or unsafe to use if cannot relax old stress. The aims of this study are to study and predict the stress relaxation at various loading rates under the compressive load. The results of experiments on closed cell polyvinylchloride foam vary from 0.1 to 500 mm/min represented that difference loads effected to stress relaxation. Generalized Maxwell with Prony’s series are applied to predict stress relaxation behavior at 0.1 and 500 mm/min. The comparison results with actual test data found that both methods are indifferent and appropriate to replace the destructive method.

This research described to the determine an optimization mathematic model using response surface methodology in central composite design method and artificial neural network (ANN) for predicting the of tensile shear and nugget size in the zinc coated steel JIS G3313. The following resistance spot welding (RSW) parameters were studied: the welding current, welding time, and electrode force. The resulting materials were examined using tensile shear tests which were observed nugget size and microstructure with scanning electron microscopy (SEM). The microstructure phenomenon could be explained by the welding optimum condition that fine pearlite and intensity in heat affected zone. The research results reveal that an optimum RSW parameters were welding current of 12 kilo amperes, welding time of 9 cycle and 1.5 kilo newton electrode force. The fine acicular ferrite occurred in the nugget size, which results in increased welding material high mechanical property. The ANN model with the proposed mathematical model, which tensile shear represents 3 neurons for the input 10 neurons for 1 hidden layer and 1 output neurons (3-10-1). The ANN model was developed to establish of the nugget predict represents 3 neurons for the input 5 neurons for 1 hidden layer and 1 output neurons (3-5-1). The mean square error (MSE) and coefficient of determination (R2) for tensile shear predict was showed that of 0.0026 and 0.956 respectively, which nugget size predicted MSE of 0.0004 and R2 of 0.958. This research, the related manufacturing sector can use research data and mathematical models was used to predict and quality control of the RSW processes to obtain tensile shear and the nugget size according to the acceptance criteria.

Hotel’s service industry has an important role toward economy and basic structures of transportation and tourism. Due to recent in competitive condition, hotel businesses must adapt and change in order to satisfy market’s needs by using internal resources of the organization to create usefulness and high efficiency. This study applied VSM technique to analyze and compare waste in Logistic management and hotel supply chain of two hotels as case studies in Sukhothai province, which were independent hotel and chain hotel along with applying Why Why Analysis and ECRS technique to improve efficiency by doing fieldwork to collect data, observing, and interviewing. The results after improving Hotels’ Logistics’ efficiency found that; case study 1 could reduce two NVA activities, which saved 7.15 minutes and was counted as 3.94% decrease, and one NNVA activity, which saved 5.10 minutes and was counted as 1.37% increase. This caused VA activity to increase for 1.37%; case study 2 could reduce two NVA activities and saved 5.20 minutes, which was counted as 0.31% decrease. This caused NNVA and VA activities to increase for 0.32% and 0.01% accordingly.

This research is to apply a Quality Function Deployment (QFD) technique for designing and developing rubber wood furniture of a kindergarten classroom. The objective of this research is to design and create the classroom furniture by focusing on the shape and usability according to the user requirements. The methodology began with a survey in the kindergarten classroom instruction in order to specify of the sample groups. After that the user requirements were collected by using the designed questionnaires. The collected data from the questionnaires, such as the importance requirement scores, was calculated and then analyzed by the QFD technique. The analysis of QFD technique was divided in to two matrixes, including the furniture product planning matrix and the furniture part deployment matrix. The furniture product planning matrix was related to translate the user requirements to the technical requirements, while the furniture part deployment matrix was about the translation of the technical requirement to the part characteristics. The results of this research showed that the QFD technique was able to design and develop the shape and usability of the kindergarten classroom furniture that responded to the user requirements. The survey results from the users revealed that the average of satisfaction values in case of all new products were greater than that of the previous products from 3.437 scores to 4.373 scores, which increased approximately 22.23 percentage.

Thai sail windmill (TSW) is a local machine of Thailand now using for pumping brine to the salt farms. TSW is a horizontal axis wind turbine that the blade is a triangular shape made of canvas. Traditional TSW efficiency is typically about 10-17%. However, it has been now developed and augmented its efficiency until 30-35%. Therefore, due to a low construction cost, an uncomplicated structure and a higher efficiency, these things encourage TSW more interesting for research. By the way, the wind turbine simulation is one significant research topic because the accurate simulation can bring about the evaluation of torque, power and efficiency correctly in another condition without the experiment. So, the simulation is very helpful to design the blade of the wind turbine. The purpose of this article is to perform the TSW simulation based on the blade element momentum theory to appraise the efficiency and to validate results with the experiment data. The efficiency evaluation would be regarded by 4 manners of the tip pitch angle as follows: 5, 10, 15 and 20 degrees. The results show that the TSW efficiencies estimated by the simulation are accurate at the tip pitch angle of 10, 15 and 20 degrees in the range of tip speed ratio of 2.0-3.5 whose average percentage error is about 7.0%.

Wind energy potential analysis is a design key to maximize wind turbine efficiency and annual energy output. Typically, the annual wind speed frequency is represented by a Single-Weibull distribution curve in spite of strong and calm wind patterns could occur through a year in many regions in the world, Thailand for instance. For this reason, wind energy potential should be analyzed by Multiple-Weibull distribution curves which are the representative of the meteorological seasons due to the monsoon’s effect. Therefore the objective of this study is to compare the accuracy of the Single-Weibull distribution and the Multiple-Weibull distribution in assessment of wind energy potential. The comparison was made between these two statistical distribution functions and the actual wind speed distribution (measured wind speed frequency) in order to determine the level of credibility of these two distribution functions. The wind speed data employed in this study was measured at Lamtakhong dam site in Nakhon Ratchasima province, Thailand. As the results, the error between the Single-Weibull distribution was 16.46% where the error between the Multiple-Weibull distribution was 14.82%, it was revealed that the smaller error, the higher reliability. Two of the most widely used wind turbines (Enercon E-30 and Windspot) were selected to verify the Multiple-Weibull concept. Approximately 40% increase in annual energy yield by using this method. So, the results confirmed that the Multiple-Weibull distribution is valid for the assessment of the annual energy production of wind turbines. Therefore, this will be a practical method for achieving the optimal design of stall-regulated wind turbine in the further work.

Moderation effect analysis or interaction analysis is an analysis aim to investigate whether the causal relationship between pair of variables, antecedent and outcome, was changed subject to change in specified values of moderators in pick-a-point fashion or in a range of values from Johnson-Neyman region. Test could be conducted through bootstrapping algorithm or t-test. In order to test for conditional effects of moderators, t-test and/or bootstrapping still being adapted with some mathematical manipulation and also with much helpful of line graph.

This academic paper is an article that presents the overview and situation about the fifth generation of mobile communication technology or called 5G for short, which should be available in Thailand by 2020. The content of this paper introduces the evolution of mobile communication technology. Then, the driving factors of this emerging 5G technology, the important technologies that support 5G, the important requirements for 5G technology development and the enhancements of this technology (e.g., the data speed that increases 20 times when compared to 4G and very low latency) and the 5G use cases or applications are also described. Furthermore, this paper also presents the status of 5G in other countries and in Thailand. Thus, this paper is an appropriate start for researchers or anybody who wishes to learn more about 5G technology that will provide the services in the near future.

This research aimed at synthesizing the geopolymer of water treatment residue and palm oil fuel ash using proper suitable SiO2/Al2O3 ratios by varying the results of compressive strength test and also to examine the quality and microstructure of solidified waste cubes after the maximum of 60 days curing. In the test, the microstructure analysis techniques of XRF XRD SEM were employed. The findings revealed that the proper ratios of SiO2/Al2O3 in synthesizing geopolymer at 2.50 could develop geopolymerization reaction. (In SiO2/Al2O3 test were 1.77, 2.00, 2.50 and 3.00) It was also found that the synthetic geopolymer with optimum compressive strength at 40.56 Ksc. In employing the microstructure analysis technique of XRD and SEM, the changes inside geopolymer structure both before and after the mixing were found. The results can indicate the developing of geopolymerization reaction and synthetic geopolymer products inside the structure of Aluminosilicate source regarding the internal changes as follows; it was found that the peak of Quartz, Potassium Aluminum Silicate (KAlSi2O6), and X-rays diffraction had been superseded by the structure solid of Sodium Aluminum Silicate Hydrate (Na96Al96Si96O384.216H2O; NASH). It was also found Silicon, Aluminum, and Sodium at the same bonding position structure of NASH. As a result, the synthesis of the geopolymer of water treatment residue and palm oil fuel ash can developing strength and changing inside geopolymer structure by appear geopolymer product. Both starting materials can be synthesized and applied in environmental filed.

The objectives of this study were to study the factors that affect the work safety of employees in the automotive parts manufacturing industry according to the supervisor opinion and study the knowledge and skills necessary to manage the safety in the operation of employees in the automotive parts production line. The samples were the supervisor of the production department of the automotive parts manufacturing industry in the areas of Rayong, Chonburi and Chachoengsao. Questionnaires and statistics used in the analysis were frequency, percentage, mean and standard deviation. The results showed that the factors that affect the safety of the employees in the automotive parts manufacturing industry as a whole were at a high level. (x􀴤 = 4.08) Including factors on each side, with an average of all levels, The most average aspect is the working environment. (x􀴤 = 4.23) The person with the lowest. (x􀴤 = 3.94) The knowledge and skills necessary for the supervisor to manage safely in the overall picture were at a high average. (x􀴤 = 4.00) Especially the knowledge of the operation is the highest average. (x􀴤 = 4.08) Which the skills of good leaders that the supervisor or the senior management must use a lot of technical skills including knowledge and expertise in the operations of that department to resolve problems with subordinates.

Nowadays, healthy eating is very popular. People start to cook their own food from existing cooking ingredients. However, sometimes they do not know what food can be cooked from existing ingredients. Therefore, they cook the same food, resulting in monotonous eating and not enjoy cooking. This research article presents the design and development of a system for cooking recipe sharing and cooking recipe finding by an image of ingredients using deep learning techniques. Users can use the application on mobile devices to share cooking recipes. Moreover, users can take a picture of ingredients that users already have in the kitchen such as garlic, pork, vegetables, etc. and send that picture into the system to search for cooking recipes from existing ingredients. This process will make users convenient for searching cooking recipes. The main components of the system include (1) A mobile application for general users developed with React Native, which users can add cooking recipes and search for cooking recipes by entering the ingredient names. Also, the user can use the mobile device to take a picture of ingredients to find cooking recipes, (2) Web application developed on the MERN stack for system administrators, which system administrators can add keywords of the search term for ingredients and test the model that has been created, and (3) Deep convolutional neural network using the YOLO algorithm through the Darknet library for creating the image recognition model. The model has taught to be able to recognize 20 types of ingredients using 100 images of each type of ingredient. After training our model for 36,000 rounds, the model has an average loss of 0.0408 with the precision, recall and F1-score at 0.96, 0.98 and 0.97 respectively.

The purpose of this study is to present the comparison of selection and mutation in genetic algorithms to identify the most accurate parameter of examination schedule problem. Which includes 1) The group of students studying in the same course must take the same exam. 2) A student will have to take 1 examination at same time. 3) The number of students for each examination must not exceed the class capacity. 4) A proctor cannot supervise more than two sessions in the same day. 5) No student should have examinations on consecutive sessions. This study examined the selection based on three methods: Roulette Wheel Selection, Ranking Selection, and Tournament Selection. Similarly, three different methods were employed for mutation namely Swap Mutation, Insertion Mutation, and Inversion Mutation. In addition, the study investigated the most accurate parameter to determine the result by adjusting the probability of mutation, size of population, and the number of generations in the experiment. The result demonstrated that the most accurate parameter was from Tournament Selection and Swap Mutation where the probability of mutation is 75 %. The results showed that the Fitness Function average was 6,168 from 7,350. The experiment also revealed that the number of generations that provided the highest average Fitness Function was 365 generations.

Mediator is a hidden variable that transmitted effect of antecedent variable to its outcome. There could be single or multiple mediators in any SEM model. In multiple mediator’s facet, parallel mediation or serial mediation could be addressed through knowledge challenged by expertise or literature. And, if researchers need to know what variables can possibly change the relationship in any or all paths of mediation model, an analysis through moderated mediation model should be addressed.

This research aimed to present the application of cost management system in the wood products industry. The case study is applied Activity-Based Costing (ABC) with a product of wooden stairs group, in order to determine the cost of production per unit which guided to cost reduction approach and compared with traditional costing methods. The production costs comprised of direct costs and indirect costs, including overhead costs. The factory had no appropriate cost allocation used for overhead cost because the traditional costing systems did not comply with actual production quantities and production times. This research then applied the ABC costing system and proposed applicable cost drivers with production activities to allocate overhead production costs. The proposed cost system was calculated using Microsoft excel. This work started from production costs and activities classification. The cost collection and cost evaluation systems were designed. Then, the activity value was analyzed and the cost drivers were determined for appropriated cost allocation criteria. After the costs of activities are calculated, the cost per unit of product calculation from the ABC cost system was compared to the traditional system. The new model of costs is more precise. As a result, the cost was reduced by 5.98%. The results also reflect non-value-added activities. This is important for executives to improve production efficiency and to manage production costs.

The purpose of this research is to study administrative law, the practice of arbitration under the Arbitration Act B.E. 2545, foreign arbitration laws and the problems of arbitration in administrative construction contract of Thailand in comparison with foreign countries, namely Germany, France, England and the United States. This research emphasized on studying construction contract cases in which a party is a government agency and the private sector based on author experience in order to provide solution and recommendation for the development, improvement or amendment of Thailand administrative law related arbitration process. The research found that the main factors that make government still have to face problems arising from dispute resolution by arbitration and the dispute is proposed to administrative court causing consumption of time and financial expense is the lack of substantive and procedural laws for specifying the compulsory details in preparation of an arbitration agreement in administrative construction contact that is not yet comprehensive and still inadequacy. The comparison of foreign laws found that some countries have established rules for preparation of arbitration contract in addition to general principles included specification of subject matters of dispute that can be resolved by arbitration and maximum amount of money for which the arbitrator can order the parties to pay when the decision is made. Therefore, the study proposes to establish a new law for administrative construction contact with such criterions included.

The objectives of this research were to: 1) study the success of online business entrepreneurs in the digital age; and 2) examine factors contributing to the success of online business entrepreneurs in the digital age. This research employed quantitative and qualitative research methodologies. In the quantitative research, the sample consisted of 260 online business entrepreneurs, obtained via multi-stage sampling. The sample size was determined based on 20 times the observed variables. Data were collected with the use of a questionnaire and analyzed with a structural equation model. For the qualitative research, in-depth interviews were conducted with 15 key informants including online business entrepreneurs and academic persons in the field of marketing. These informants were selected by purposive sampling. Data were analyzed with content analysis. The research findings showed that: 1) the success of the online business entrepreneurs was rated at a high level; 2) the characteristics of entrepreneurs, information technology, business strategies, and management innovation, all contributed to the success of online business entrepreneurs in the digital age with .05 level of statistical significance. Moreover, the findings also revealed an important point that entrepreneurs in the digital age needed to examine the needs of customers and respond to such needs promptly so that a marketing opportunity could be gained quickly. This could be done with the use of technologies in the digital age. Additionally, online entrepreneurs also needed to adjust their marketing strategies according to the market situations to ensure that they are competitive. They also needed to apply management innovation in the adjustment of business strategies to increase sales and expand their markets. These would align the business according to customer needs, leading to customer satisfaction, word of mouth communication among customers, repeat consumption, and brand loyalty. These findings can be used as guidelines for the development of success of online business entrepreneurs in the digital age by enhancing their potential in terms of marketing competitive advantage, creating and improving trading networks, and applying innovations and modern technologies in the development of their online businesses.

The aims of this research were compared the electricity generation and COD removal between waste glycerol and tannery wastewater with microbial fuel cell technology. The results showed power generation from waste glycerol and tannery waste water were obtained 0.0018 mW m-2 and 6.2 mW m-2, respectively. The COD removal efficiency can be obtained from waste glycerol and tannery wastewater 80 and 90%, respectively. The nitrogen removal efficiency from tannery wastewater in form of TKN (Total Kjeldahl Nitrogen) can be obtained 50%. Moreover, there are 2 parameters that indicated to oxidation-reduction reaction, which important reaction for microbial fuel cell are cyclic voltammetry (CV) and coulombic efficiency (CE). Cyclic voltammetry (CV) was showed the oxidation-reduction on electrode. Coulombic efficiency (CE) from waste glycerol and tannery wastewater were 7.62 and 15.6 %, respectively. There are parameters that showed the efficiency of electricity generation with 2 of substrates from microbial fuel cells. Therefore, microbial fuel cell technology that can be electricity generation from tannery wastewater better than waste glycerol.

The objective of this research was to study the optimum conditions for production of biodiesel by using hydrodynamic cavitation reactor through transesterification reaction with waste cooking oil and methanol, using potassium hydroxide as a catalyst. The effect of parameters on yield of biodiesel were focused. The parameters were studies, such as inlet pressure (2, 3 and 4 bar), methanol to oil molar ratio (4:1, 6:1 and 8:1), concentration of catalyst (0.5, 1 and 1.5 wt%) and reaction time (20, 30 and 40 minute) when reaction temperature (room temperature) was fixed at 28 °C. The experimental results showed that optimum conditions for biodiesel production from waste cooking oil were inlet pressure at 4 bar, methanol to oil molar ratio of 6:1, catalyst concentration of 1 wt% and reaction time at 30 minutes. Under the conditions, the obtained yield of biodiesel was 93%. In addition, the properties of the obtained biodiesel from optimum conditions were evaluated and it was found that the properties of biodiesel product was in the range of standard requirements of both biodiesel and low speed diesel fuel. In summary, hydrodynamics cavitation reactor can be applied to biodiesel production with one stage of transesterification reaction.

This paper is concerned with scheduling in Flexible Manufacturing Systems (FMS) using a Fuzzy Logic (FL) approach. Four fuzzy input variables; machine allocated processing time, machine priority, machine available time and transportation priority are defined. The job priority is the fuzzy output variable, showing the priority status of a job to be selected for next operation on a machine. The model will first assign operation of parts to machines under the given production plan and then determine the input sequence of the assigned operations for each machine based on a multi-criteria scheduling scheme. A complete fuzzy scheduling algorithm is developed to solve the operation allocation and operation scheduling problems in FMS environments aiming to approach the objectives of minimizing mean flowtime, maximizing machine utilization and balancing machine usage. The test results demonstrate the superiority of the fuzzy logic approach in most performance measures.

This paper describes a study of travel speed of vehicles passing community which located on roadside of rural highways. The objectives of this paper were to survey the number of vehicles which drove with excessive speed over speed limit of both outside and inside community area. To survey the operating speed and to survey operating speed after traffic engineering measures installation on study area. Ban Pa Yang community, Muang district in Nakhon Si Thammarat (NST) was selected as a study area. Traffic engineering measures will be selected from the speed survey results of vehicles passing community. The study results showed that the top three volumes of vehicles passing community were motorcycles, private cars and pick-up trucks, respectively. The survey results of operating speed showed that private cars drove passing community with excessive speed over speed limit of highways, however, the operating speed of trucks were gradually reduced before entering community and increased over speed limit again when passing community zone. Motorcycles were the only one vehicle type which drove lower than speed limits of both outside and inside community zone. Transition zone area was a traffic engineering measure which was defined the distance for reducing speed before entering community by calculated from the data of speed survey outside community area. The average operating speed outside and inside community study area was evaluated by paired-sample t – test statistic. The survey results showed that the average operating speed of trucks and motorcycles after measures installation on transition zone were lower than the average operating speed of trucks and motorcycles before measures installation significant at a confidence level of 95%.

This article presents an experimental result of low C/N ratios with ranges of 3.2:1 to 5.9:1 of composting of excess sludge from activated sludge wastewater treatment systems of concentrated latex factories. The composting experiments were investigated based on test conditions of different compost materials used, with aeration and with no aeration, as well as with seeding and without seeding. In addition, the investigation on the possible use of the obtained compost products as fertilizer on plant growth was conducted. The results indicated that composting was not reached in the thermophilic and mature phases. The slow decomposition of OC occurred during 90 days composting. Loss of N was significantly determined, in particular in the aerated composting units, but K increment was observed. The results indicated that the composting of mixtures of excess bio-sludge, ash, and coconut husk with and without seeding and aeration made compost products compliant with Thai organic fertilizer standards, especially in terms of pH, P2O5, K2O, As, Cd, Cr, Cu, Pb, and Hg. With the results tested on plant growth, the possibility of the use of compost products as fertilizer as experimented with marigolds, illustrated that compost products from a mixture of excess bio-sludge, ash, and coconut husk with seeding and aeration had potential to be used as fertilizer which was equivalent to 15:15:15 chemical fertilizer, in particular in terms of plant height increase rate and numbers of flowers achieved.

This paper analyzes the rate of return on gold bar investment with the Discrete-Time Markov Chains. The input data are from January 1, 2014 to April 9, 2016. Our objective is to determine the selling and buying prices that yield the highest annual rate of return. We recommend buying gold bars when the buying price hits 17,900 Baht/1 Baht gold and when the selling price is higher than 18,300 Baht/1 Baht gold, resulting in the annual return rate of 204% per year. In addition, if gold bars can be bought at the price lower than 20,750 Baht/1 Baht gold, the return rate can be at least 0.61% higher than a bank time deposits account with 3% interest rate.

This paper presents the current-mode signal conditioning circuit for single active resistive sensor which composed of op-amp in conjunction with current conveyors. The research found that the proposed circuit proves better quality in term of linearity when comparing to the traditional signal conditioning circuit. This circuit provides high accuracy with error less than 1% and linear output related to resistance changes. The results of PSpice simulation when emulate with RTDs sensors have shown a good compliance with circuit analysis.