จำนวน Repository ( 167 )

การวิเคราะห์อิทธิพลที่มีผลต่อผลผลิตพืชไร่ทางเศรษฐกิจที่สำคัญในพื้นที่เพาะปลูกเขตภาคกลางของประเทศไทยด้วยตัวแบบทางคณิตศาสตร์อย่างมีประสิทธิภาพ
การวิเคราะห์อิทธิพลที่มีผลต่อผลผลิตพืชไร่ทางเศรษฐกิจที่สำคัญในพื้นที่เพาะปลูกเขตภาคกลางของประเทศไทยด้วยตัวแบบทางคณิตศาสตร์อย่างมีประสิทธิภาพ

The objectives of this research are to propose an approate and efficient model for analyzing rice corn and sugar yields data. A linear mixed model (LMM) with spatial correlation following the conditional autoregressive model (CAR) was adopted. The results show that for rice yields if the amount of rainfall in a harvest season increases 1 mm the yields will decease by 25.74 tons. if the temperature in the harvest season increases 1 Celsius the yields will decease by 212.60 tons and according to the trend the yield will increase by 15.80 tons each year. For sugar cane yields if the amount of rainfall in the harvest season increases 1 mm the yields will decease by 51.35 tons. if the temperature in the harvest season increase 1 Celsius the yields will incease by 121.30 tons and according to the trend the yield will increase by 29.93.80 tons each year. For corn yield if the amount of rainfall in the havest season increases 1 mm the yields will incease by 73.45 tons. if the temperature in he havest season increases 1 celsius the yields will decease by 40.44 tons and according to the trend the yield will increase by 1.74 tons each year.

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การพัฒนาและสร้างเตาสำหรับต้มใบสับปะรด
การพัฒนาและสร้างเตาสำหรับต้มใบสับปะรด

Recently Baan Pasang Wiwat Pineapple Leaf Community Enterprise Nanglae Sub-district Muang District Chiangrai has used a spherical cooking stove made of stainless steel to cook pineapple leaves. The cooking capacity was 40-50 kilograms each time and the cooking time was approximately 4 hours. The fuel was wood which was used for about 50 kilograms during the whole cooking process. The researcher has thought of saving the quantity of wood burned for coking by designing a new stove which would function like a charcoal kiln. It was a closed stove which would be automatically closed when the wood changed to charcoal to prevent the oxygen from entering. Then the fire would be put out and only the charcoal remained. The experimental result was that the minimum quantity of wood could be used to cook 10 kilograms of pineapple leaves and the process took 3.5 hours. However it is still difficult to find wood for use as fuel because it is rare and expensive. To solve such problem the researcher has developed and designed a pineapple leaf cooking stove which uses rice hulls as fuel. Rice hulls are easy to find and cheap so it is perfect for use as alternative fuel. In addition the size of the newly developed stove fits is suitable for completely cooking pineapple leaves by using one lot of rice hulls. After boiling 50 kilograms pineapple leaves with the stove powered by rice hulls by adding an amount of 21 kilograms of rice hulls the result was that the boiling time reduced from 4 hours to 1.5 hours. The cost of rice hulls used for each boiling was only 7.50 baht.

2560
นวัตกรรมคอนกรีตต้นทุนต่ำไหลเข้าแบบง่ายโดยการใช้เถ้าทิ่้ง
นวัตกรรมคอนกรีตต้นทุนต่ำไหลเข้าแบบง่ายโดยการใช้เถ้าทิ่้ง

This research presents a study of the compressive strength porosity chloride penetration resistance to carbonation and corrosion of self-compacting concrete containing fly ash ground rice husk-bark ash and ground bottom ash. Portland cement (CT) is partially replaced with pozzolans 0-40% by weight of the cementitious materials. Fly ash ground rice husk-bark ash and ground bottom ash have a high potential to be used as a good cementitious material. The results show that the compressive strength and low porosity of self-compacting concrete improves substantially with partial replacement of Portland cement with fly ash. Self-compacting concrete mix cement containing 20-40% of pozzolans can be used to make cementitious materials. The use of fly ash ground rice husk-bark ash and ground bottom ash produces concrete mix with good strength and resistance to chloride and corrosion.

2557
การวิจัยด้านวัสดุปูนฉาบที่เป็นมิตรต่อสิ่งแวดล้อม
การวิจัยด้านวัสดุปูนฉาบที่เป็นมิตรต่อสิ่งแวดล้อม

This research studies the potential for using waste ash from industrial and agricultural by-products as a plastering material. This paper presents a study of the water requirement compressive strength flexural strength normal consistency setting time and air content of plastering material containing classified fly ash (FA) and ground rice husk ash (RHA). Fine fly ash and fine rice husk ash have a high potential to be used as a good pozzolanic material. The use of finer pozzolan results in a stronger and denser mortar which is due to better Q!spersion and filling effect as well as an increase in the pozzolanic reaction. Fine fly ash and fine rice husk ash can be incorporated into mortar as replacement of the mortar mix cement for the plastering. Mortar mix cement containing 20% fine fly ash and fine rice husk ash can be used to make plastering materials.

2555
Use of disposed waste ash from landfills to replace Portland cement
Use of disposed waste ash from landfills to replace Portland cement

In this study waste ash was utilized as a pozzolanic material in blended Portland cement in order to reduce negative environmental effects and landfill volume required to dispose of waste ash. The influence of waste ash namely palm oil fuel ash rice husk ash and fly ash on compressive strength and sulfate resistance in mortar were studied and evaluated by some accelerated short–term techniques in sodium sulfate solutions. Ordinary Portland cement (OPC) was partially replaced with ground palm oil fuel ash (POA) ground rice husk ash (RHA) and classified fly ash (FA). Single pozzolan and a blend of equal weight portions of POA RHA and FA were also used. The resistance to sulfate attack of mortar improves substantially with partial replacement of OPC with POA RHA and FA. The use of a blend of equal weight portions of FA and POA or RHA produced mixes with good strength and resistance to sulfate attack. POA RHA and FA have a high potential to be used as a pozzolanic material.

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