Engineering Journal of Research and Development

พฤติกรรมของตะกอนแขวนลอยบริเวณแม่น้ำเจ้าพระยาตอนล่าง

2019-06-04T22:01:10+07:00

The Lower Chao Phraya River is area that is affected by changing of sea level resulting in two directions of flow and sediment transports depending on the upstream water levels and sea water levels. The study of sediment behavior in this area is important for solving problem about water transportation and water management. Hydraulics data were collected by Acoustic Doppler Current Profiler, echo sounder and suspended sediment equipment in the Lower Chao Phraya River between November 2015 and May 2016. It is found that the diameter of suspended sediment is 0.027 mm. Sediment settling velocity is 21.31 mm/s. Spring tide and neap tide are the most effect to behavior of suspended sediment. Sediment load equations are presented by three variable linear equation q = (9x10^-5)Q – 0.0002D in spring tide and q = (4x10^-5)Q + 0.0032D in neap tide. R² are equal 0.6484 and 0.6007 respectively.

การศึกษาความสัมพันธ์ระหว่างปริมาณน้ำฝนสะสมกับระยะเวลาดินพังทลายบนแบบจำลองลาดเอียงทางกายภาพ

2019-05-28T16:36:37+07:00

This paper presents a study of the relationship between accumulation rainfall and soil landslide time on a physical earth slope model .Soil samples were collected from the soil landslide sites and tested for basic engineering properties of two soil masses and the rainfall from previous researches was more than 100 millimeters per day. As a result, soil landslide on the slope and two slope models were used. The slope was 160 hours per slope. To study cumulative settlement patterns and cumulative lengths. Based on the results of the study, the basic properties of soil samples can be USCS classified is SM. the results show that when the rainfall accumulation reaches a period of 48 hours, the two slopes will collapse and the cracks will follow. Low water permeability will initiate sudden slump and low slope. Over long periods of time, soil will continue to subsist more and more. And based on the cumulative crack length study, it is evident that soil with high water permeability on slope increases with the cumulative length of cracks. At the same time, soil with low water permeability should be monitored and preventive measures should be taken.

ความสัมพันธ์ระหว่างความเค้นและความเครียดของผนังอิฐมอญภายใต้แรงอัดแกนเดียวที่ทำมุมกับแนวการก่ออิฐ

2019-05-28T16:54:17+07:00

Masonry infilled in reinforced concrete frames affects the behavior of structures subjected to lateral loading. However, there are few researches about compressive behavior of masonry panel in Thailand. The objective of this study is testing the masonry panels subjected to compressive loading. The panels are about 760x760 mm² in width and height. They are constructed with clay bricks, 65x160x40 mm³ for dimensions, usually used in construction industrial. The compressive loading directions incline to the bed joint varied 0, 15, 30, 45, 60, 75 and 90 degrees. The test results indicated that the inclined angle between loading direction and bed joint significantly affects the strength and failure characteristic. The failure criterion and stress-strain relationship of the masonry panel subjected to compressive loading are proposed based on the tested data.

การคำนวณศักย์ไฟฟ้าที่รางระหว่างสถานีจ่ายกำลังไฟฟ้าขับเคลื่อนสำหรับระบบรถไฟฟ้ากระแสตรง

2019-05-28T17:01:27+07:00

This paper presents a mathematical model for rail potential calculation in the DC electrified railway with two traction substations. The rail potential and traction substation voltage are essential for supply equipment, passenger safety and railway infrastructure protection against corrosion, all of which must comply with requirements and standards. The classical and simplified mathematical models are described in this study to analyses the rail potential and current. In addition, the simplified equations for estimating the rail potential and traction substation voltage are derived to simply determine the stray current. These equations can be used to analyses and calculate the stray current based on the approximate rail potential. They are also validated according to the equations in EN 50122-2

แบบจำลอง CFD-DEM สำหรับพลศาสตร์ของก๊าซ-ของแข็งในระบบฟลูอิไดซ์เบดแบบต่อเนื่อง

2019-06-04T22:01:10+07:00

Gas-solid two-phase flow is the main phenomena in the fluidized bed system. This paper presents a coupled Computational Fluid Dynamics and Discrete Element Method (CFD–DEM) approach to simulate the behavior of fluid–particle interaction in a continuous fluidized bed dryer. DEM is employed to model the granular particle system, whilst the CFD is used to simulate the fluid flow by solving the locally averaged Navier–Stokes equation. Influence of the superficial gas velocity, mass flow rate, particle temperature and residence time of solid particles on the drying process have been reported. The prediction of residence time can help to optimize continuously operated fluidized process.

การประเมินศักยภาพเชิงพลังงานและเอกเซอร์จีของเครื่องอบแห้งพลังงานรังสีอาทิตย์ชนิดอุโมงค์ลม

2019-05-28T18:35:56+07:00

This article is an analysis of the energy and exergy of mango drying using a solar tunnel dryer with forced convection. The experiment was conducted to find the Energy Utilization Ratio (EUR) of the dryer and apply the second law of thermodynamics in the analysis of the exergy on the solar collector and the solar tunnel dryer including the ability to evaporate water from the product to the energy of the drying process. The results obtained from the energy and exergy analyzes could be used to develop the potential of the renewable energy drying system in terms of maximum efficiency.

การสร้างข้อต่อแรงเสียดทานต้นแบบเพื่อพัฒนาชุดจำลองความชรา

2019-05-28T19:05:27+07:00

This research was creation of friction joint prototype to develop a model of aging. The design from elderly body change data in muscle decreases with age and uses the principle of friction. With trial participants adult aging 30-34 years, 4 peoples and elderly aging 59-64 years, 5 peoples. Ergometer test compares the ratio between steady heart rate with maximum heart rate. During participants elderly with participants adult not wear and wear friction joint prototype. The result, ergometer test of participants elderly have a ratio of steady heart rate with maximum heart rate is significantly different with ergometer test of participants adult not wear friction joint prototype and ergometer test of participants elderly have a ratio of steady heart rate with maximum heart rate is no significantly different with ergometer test of participants adult wear friction joint prototype. The wearing of friction joint prototype in adult similar to the elderly more than not wearing. Because wearing friction joint prototype increases a burden on the body. Make more tired, Uncomfortable movement, the body uses more energy, Static muscle strength decreases with age. Can simulate the elderly.

APPLICATION OF A QECN-QFD TO DESIGN AN ENVIRONMENTALLY-FRIENDLY ONE-HANDED LIPSTICK PACKAGING

2019-05-28T19:18:01+07:00

The 12-step QECN-QFD (Quick-easy-customer’s needs quality function deployment) was proposed to design an environmentally-friendly one-hand lipstick packaging. By using the information from the survey to identify the actual customer needs and the resulted requirements were transformed into engineering characteristics for further QFD application. It firstly starts with a questionnaire design and distribution, collection and data analysis via a focus group of 5-knowledgeable people to help discussing and listing the quality dimensions of one-handed lipstick packaging. Six dimensions was then achieved and used as basis for laying out the survey questionnaire, focusing on positive/negative critical incidents. Twelve questions were distributed with 33 respondents and analyzed (Step 1-4). The resulted analysis were calculated and used for eliminating the non-relevant questions. The remaining questions were further used as a basis for designing the satisfaction survey questionnaire of about 20 questions. The results of the survey and analysis with 94 respondents were used to identify the actual customer needs and the resulted requirements were further transformed into engineering characteristics (Step 5-11). The resulted engineering characteristics were finally analyzed by QFD method and the possible ways of packaging were designed to minimize the non-used content of the lipstick compartment left over. The new lipstick compartments design were proposed and compared with several available options by calculating the scores according to the required criteria. The best solution for one-handed lipstick packaging with environmental-friendly one was therefore selected (Step 12). The detailed drawing was then visualized through the sketches using Solid Work Program and the prototype of the designed one-handed environmental-friendly lipstick packaging was finally created using 3-D Printer. The round-shape body prototype with a flipping opening mechanism at the top-cap made it easy to be opened by one-hand. The slide- up button was convenient to push up with several steps of locking, making it suitable and perfect usage at all ongoing day; especially, for traveler, teenager, elder, and women-on- going. The detached ring at the sleeve could be twisted and pulled off easily, help minimizing the waste of lipstick content. This packaging was also designed to be reused.

LABORATORY ASSESSMENT OF LONG-TERM DURABILITY OF SOME DECORATING AND CONSTRUCTION ROCKS

2019-05-28T19:34:12+07:00

การทดสอบดัชนีความคงทนต่อความผุกร่อนได้ดำเนินการจำนวน 100 รอบใช้หิน 13 ชนิดโดยมีวัตถุประสงค์เพื่อหาความคงทนของหินในระยะยาว ตัวอย่างของหินแบ่งออกเป็น 4 กลุ่มคือ กลุ่มหินบะซอลต์ หินคาร์บอเนต หินทรายและหินแกรนิต การทดสอบในระยะยาวมุ่งเน้นเพื่อหาความแตกต่างระหว่างอัตราการผุกร่อนของหินที่มีกำลังกดใกล้เคียงกัน การทดสอบมี 3 ชุดคือ ภายใต้สภาวะแห้ง เปียกและสภาวะความเป็นกรด ผลที่ได้ระบุว่าการเสื่อมสภาพของหินคาร์บอเนตโดยเฉพาะอย่างยิ่งหินทราเวอร์ทีนเพิ่มขึ้นอย่างมากเมื่อหินเหล่านี้สัมผัสน้ำและกรดในระยะยาว ปริมาณสนิมและความพรุนเป็นตัวการสำคัญในการเร่งอัตราการผุกร่อนของกลุ่มหินบะซอลต์ ชนิดและพันธะยึดติดของวัสดุเชื่อมประสานเป็นปัจจัยสำคัญต่อความคงทนของกลุ่มหินทรายที่นำมาทดสอบ น้ำและกรดมีผลกระทบน้อยต่อความคงทนของกลุ่มหินแกรนิต

ระดับความเข้มข้นและองค์ประกอบทางเคมีของฝุ่น PM2.5 ในพื้นที่เมืองนครราชสีมา

2019-05-28T19:52:58+07:00

This research investigated the PM_2.5 concentrations and chemical compositions – black carbon, ionic species, and elements – in urban and industrial areas of Nakhon Ratchasima city. For each area, 41 samples were collected consecutively from its sampling location for 4 months (Nov. 2016 – Feb. 2017). Results show that the mean value of the 24-hr average PM_2.5 concentration in the industrial area was significantly higher than the urban area, with a 95% confidence level. In contrast, the mean value of black carbon concentration in the urban area was higher. Analyses of 7 ionic species and 20 elements revealed that the mean values of 3 ionic species – Cl^-, NO^3-, and K⁺ – and 9 elements – Ag, Al, Cd, Fe, Mn, Ni, Tl, V, and Zn – were higher in the industrial area. In addition, the proportions of the chemical composition of dust in decreasing order were anions, cations, black carbon, and elements for the urban area; and anions, cations, elements, and black carbon for the industrial area. Results of Nakhon Ratchasima city study are comparable to those of other cities and useful for future modeling analysis to identify air pollution sources.