Ladkrabang Engineering Journal

Application of Kansei Engineering Techniques in the Design and Development of TV Table Furniture Products from Oil Palm Trunks

2022-02-11T10:21:43+07:00

This objective aims to apply Kansei engineering techniques in the design and development of TV table furniture products from oil palm trunks. To create an idea for the development of products that can respond to the that meets consumer needs through quantification theory type 1 (Linear multiple regression) with a Likert scale. To form of the forecast equation for showing the relationship between sentiment with product attributes and for simulating new product models. The results of the quantification theory type l revealed that five product attributes could be defined for product design: usage, contours, decoration material, product size and product form. In addition, it was found that expressions of sentiments that correlate with product attributes for design can also be include, weight-bearing, usability, shape, usable space, luxury, beauty, and uniqueness. Therefore, the results of this research can serve as a guide to help designers to define product attributes that represent the feel-good relationship for designing and developing new products in accordance with customer needs.

Development of Strategic Supplier Evaluation: A Case Study of Wood Suppliers in Furniture Industry

2022-02-08T09:56:59+07:00

This research aimed to develop decision support tools for management decision-making. The process of analyzing and choosing strategic suppliers of wood materials, which is regarded as a critical raw material in the furniture industry, was the issue of the case study. The goal of criteria development was to deal with supplier-related problems to comply with the company's strategic competitiveness. The literature review was determined to list factors that affect supplier evaluation. Then, these factors were proposed to three buying experts from the case using the index of item–objective congruence which is the assessment tool for concerned main and sub-criteria. After that, managers applied the analytical hierarchy process, which is a tool in multi-criteria decision making, to determine the weight of significance involved in the case study buying process. The evaluation process and criteria were established to assess present suppliers. As the result, the most significant three main criteria were product quality, delivery, and flexibility. According to the proposed method, the performance of five suppliers was not correlated to purchasing proportion because of price focus. The best performance supplier had 12 percent of purchasing proportion which ranked the third. The first rank of buying proportion got 35 percent which ranked before the worst performance supplier. The proposed method also supported actual supplier performance connected to improvement and strategic supplier relationship management in the future.

Dual-Band Double Circular Patch Antenna on Multilayer Substrate

2022-02-15T15:00:57+07:00

This paper presents a dual-band antenna for a wireless local area network (WLAN) system with the frequency of 2.4–2.5 GHz and 5–6 GHz. The proposed antenna is a patch antenna consisting of two circular radiation plates. They are stacked above and below the multilayer substrate, connected by wire, and fed by the coaxial probe. From simulated and measured results, the proposed antenna has an input impedance close to 50 W and |S₁₁| below -10 dB in a frequency of 2.4–2.5 GHz and 5.0-5.3 GHz, the gain is 1.9 dBi at 2.45 GHz and 2.36 dBi at 5.2 GHz, respectively. The antenna can be effectively used in both frequency bands of wireless local area networks.

Evaluation of the Particle Filtration Efficiency of Surgical Masks by Electrostatic and Light Scattering Particle Counters

2022-02-01T13:20:12+07:00

The goal of this study was to use light scattering and electrostatic particle counters to evaluate the particle filtration efficiency of surgical masks. Samples of surgical masks that have been approved by the FDA were chosen for testing in this study. Particle filtration efficiency was measured using polystyrene latex spherical particles with diameters of 0.1, 0.5, 1.0, and 1.5 µm at a face velocity of 10.6 cm/s and a test area of 17.8 cm² according to the ASTM F2299-03 standard. The light scattering and electrostatic particle counters were used to measure the upstream and downstream particle number concentrations of the test mask in order to evaluate the measured particle filtration efficiency of both counters. The particle filtration efficiency of the two counters was found to be similar based on the experimental results. It was shown that the particle filtration efficiency that obtained from both counters were in the range of 95.38–98.61%, the difference in the mean absolute percentage error of the particle filtration efficiency between the light scattering and electrostatic particle counts was about 0.99, 2.03, 1.84 and 1.79 for particles 0.1, 0.5, 1.0, and 1.5 µm, respectively. The results of the comparison suggest that electrostatic particle counters may be used to measure particle filtration efficiency in a way that is comparable to the ASTM F2299-03 standard for light scattering particle counters.

Application of Nanofiltration Membrane for Calcium Sulfate and Natural Organic Matter Removal

2021-12-20T10:13:43+07:00

The objective of this research was to study the removal efficiency of calcium sulfate and natural organic matter (NOM) using nanofiltration membrane. The membrane sheets used were obtained from GE Water & Process Technologies (model HL4040HM). The filtration experiments were determined by a dead-end filtration membrane. Factors studied were ionic strengths of calcium sulfate, pH and combined effects between calcium sulfate and NOM. The experimental results revealed that increased ionic strengths of calcium sulfate provided higher flux decline, possibly increased concentrations of calcium sulfate, thus decreased permeate flow. Solutions having high ionic concentration of 0.015 M resulted in the highest sulfate removal about 97%, thus enhancing accumulation of calcium sulfate on the membrane surface. The pH effects caused calcium and sulfate removal ranging from 71% to 93 %. For combined effects between calcium sulfate and NOM, it was found that fluxes and rejection efficiencies (both calcium and sulfate rejections) showed lower values than those without NOM.

Temperature Control of Thermoelectric Generators for Small Incinerators With Modified Fruit Fly Optimization Algorithm (MFOA)

2022-02-08T10:05:25+07:00

This paper presents the application of thermoelectric generator (TEG) plates for converting the thermal energy generated by the incinerator into electrical energy for utilization and a modified fruit fly optimization algorithm (MFOA) is employed to control the cooling system on the cold side of the thermoelectric generator plates. This energy conversion system consists of a thermoelectric generator plate, thermocouple, cooling system, voltage sensor, and microcontroller. From the implementation results, it was found that a modified fruit fly optimization algorithm can be used to control the cooling on the cold side surface to achieve the maximum temperature difference on both surfaces. The energy conversion system can generate electrical energy with a voltage of 18 V, a current of 0.85 A, at a temperature difference on both surfaces of 128^oC. Moreover, the data of this energy conversion will be recorded on the database with the internet of things (IoT) communication.

Aerodynamic Design and Optimization of Supersonic Spin-Stabilize Round Body

2022-04-12T11:48:24+07:00

The purpose of this paper is to design and analyze the aerodynamics characteristics of a spin-stabilized round shape body for enhancing the aerodynamic performance of projectile distance through supersonic regimes. In this research, the spin-stabilized round shape body 30 mm in diameters (XM-788 E1 and XM-789) are used as a benchmark model. In the first step, the static and dynamic aerodynamic coefficients of these shapes are evaluated using Computational Fluid Dynamic (CFD) in terms of K-ω SST turbulent model. The calculation results are then employed to validate with available experimental data to ensure the accuracy. Next, the Kriging response surface and Shifted Hammersley Sampling technique are used as an optimization method for drag minimization. CFD is then employed for drag prediction and stability analysis. The optimization result show that the optimized body provides up to 20.52% for drag reduction, while remaining statically and dynamically stable over the whole range of operating Mach number.

Excel Based Monte Carlo Simulation for the (Q,r) Inventory Control Model

2021-12-28T10:54:43+07:00

In supply chain management, inventory plays a key role to deal with demand and supply uncertainty aiming to guarantee a smooth flow of materials and products along the chain. This paper focuses on determining the suitable values of Q and r in the (Q,r) inventory control policy model when it was applied to the situation of nonstationary but known to be empirically discretely distributed of product demands and lead times. The total cost (TC) and service level (SL) were used to measure the policy performance using an Excel-based Monte Carlo Simulation (MCS) approach with a set of actual historical demand data from an automotive tire service store. Results from the MCS indicated that the (Q,r) model could lead to 12.36% lower TC with 2.31% higher SL, on average, when the Q and r values were determined based on empirical discrete distribution compared to that of normal distribution. Therefore, the empirical discrete distribution of demand and lead time should be utilized in a situation where the assumption of normal and other traditional distributions is invalid.

Improvement of the storage locations for the finished products warehouse: A case study of sportswear manufacturing company

2022-02-04T14:13:28+07:00

This study presents the improvement of the storage location for the finished goods warehouse in sportswear manufacturing. The objective is to increase the efficiency of finished goods storage in more operational work. In the current condition, the warehouse has stored finished goods at the non-fixed location explicitly, causing them to take long time for moving to the storage location. Therefore, the authors determined the locations for storing the products. ABC analysis with the concept of grouping analysis theory was applied to organize into groups of goods from its movement. In addition, MATLAB, software for computing the storage location on the principle of the binary integer linear program, was enhanced to determine the location for storing products appropriately by considering the moving time significantly. As a result of the study, the storage improvement by the new storage location enhances to diminish the overall storage time of the classified group A and B to 16.12 % and 11.55%, respectively. Classified group C has an average moving time of 23.71 seconds per one shelf.

The Effect of lnlet Clogging in Drainage System

2022-03-07T11:02:56+07:00

The purpose of this paper is to study the effect on drainage systems when inlets become clogged and to present a suitable inlet type for drainage systems. The Storm and Sanitary Analysis 2018 program was chosen to analyze the drainage system and the water level that occurs in the drainage of Kaeng Sua Ten Housing Estate plan 3. The inlets were rated by the degree of clogging using percentages from 0–90% against the 4 different types of inlets found in the estate. The results showed that at 50% clogging, the combination inlets and the curb opening only inlet had the lowest and highest level of flooding that not over 2 and 6 centimeters respectively. The rectangular grate inlet is suitable when considering the installation budget. The circular grate inlet is most suitable when considering driving safety. The curb opening inlet is a good choice for use in areas with low clogging risk and low volume of water intake because it is the cheapest.

FPGA Implementation of Convolutional Code for Underwater Visible Light Communication Systems

2022-04-08T09:22:50+07:00

In this work, the error-correcting code, namely convolutional code, is developed and implemented using field-programmable gate array (FPGA) is proposed for underwater visible light communication (UVLC). The Viterbi decoding using the trellis diagram is used. The transmitter is located underwater with 10w LED and the baud rate is 9,600 b/s, which is compatible with the UART communication protocol. Four avalanche photodiodes with a bandwidth of 25 MHz is used to convert the light signal to an electrical signal at the receiver. Additionally, the output signal from the APDs is amplified by using OPA2380. The input voltage target is 3.3v, which is suitable for the ESP8266. Additionally, the measured data send to NETPIE for presented on the website in the following. To verify the system performance, the measurement data is recorded for 240 minutes with a communication distance of 1.45m. The bit error rate is 1.4 × 10 ^-3; therefore, the system can correct the error and show it on NETPIE correctly. The data is measured in real-time.

A Review on Screw Conveyors for Bulk Materials in Various Applications

2022-04-01T11:10:06+07:00

Screw conveyors are widely operated for handling bulk materials in many industries. This literature review will illustrate the recent research works which relate with mineral, agriculture, biomass, and chemical sections. The mechanism of the screw conveyor seems like simple but the physics of particle handling in many fields have some different behaviors that need to be understood clearly. Hence, this comprehensive review has been revealed the theoretical flow rate formulas for the U-shape screw and enclosed the screw conveyors. Moreover, this paper gathers recent literature reviews of various applications for illustrating various results of each section that can use to be a guide for future research works.