Pretreatment of rice straw by hot-compressed water for enzymatic saccharification

Somkiat Ngamprasertsith,Sasithorn Sunphorka,Prapan Kuchonthara,Prasert Reubroycharoen,Ruengwit Sawangkeaw 한국화학공학회 2015 Korean Journal of Chemical Engineering Vol.32 No.10

The primary objective of this work was to measure the maximum amount of glucose that can be produced from Thai rice straw using hot-compressed water (HCW)-pretreatment before enzymatic saccharification. The optimal HCW-pretreatment temperature and time were found to be 180 oC/2MPa for 20-30 min. However, the concentrations of the yeast inhibitors were strongly dependent on the HCW-pretreatment temperature and time. At temperatures over 180 oC/2MPa or for more than 30min at 180 oC/2MPa in the HCW-pretreatment the combined concentration of these two inhibitors (Furfural and 5-Hydroxymethylfurfural) increased exponentially, while the glucose levels were near the maximal asymptote. At the more optimal HCW-pretreatment condition of 180 oC/2MPa for 20 min, 25±3 kg of glucose could be produced from a 100 kg of rice straw, which is potentially economically competitive with other sources.

Monitoring of Dry Cutting and Applications of Cutting Fluid for Ball End Milling

Somkiat Tangjitsitcharoen,Channarong Rungruang,Duangta Laiaddee 대한산업공학회 2010 Industrial Engineeering & Management Systems Vol.9 No.3

For economical and environmental reasons, the aim of this research is hence to monitor the cutting conditions with the dry cutting, the wet cutting, and the mist cutting to obtain the proper cutting condition for the plain carbon steel with the ball end milling based on the consideration of the surface roughness of the machined parts, the life of the cutting tools, the use of the cutting fluids, the density of the particles of cutting fluids dispersed in the working area, and the cost of cutting. The experimentally obtained results of the relation between tool wear and surface roughness, the relation between tool wear and cutting force, and the relation between cutting force and surface roughness are correspondent with the same trend. The phenomena of surface roughness and tool wear can be explained by the in-process cutting forces. The models of the tool wear with the cutting conditions and the cutting times are proposed to estimate the tool cost for the different cooling strategies based on the experimental data using the multiple regression technique. The cutting cost is calculated from the costs of cutting tool and cutting fluid. The mist cutting gives the lowest cutting cost as compared to others. The experimentally obtained proper cutting condition is determined based on the experimental results referring to the criteria.

Optimization-Based Train Timetables Generation with Demand Forecasting for Thailand High Speed Rail System

Somkiat Khwanpruk,Chalida U-tapao,Kankanit Khwanpruk,Laemthong Laokhongthavorn,Arkom Suwannatrai,Seksun Moryadee 대한토목학회 2021 KSCE JOURNAL OF CIVIL ENGINEERING Vol.25 No.9

In this paper, we propose a timetable optimizer (TO) consisting of the following parts: 1) Demand Forecasting Module 2) Train Optimization Module 3) Timetable Generator Module. TO is a specialized system for planning the train timetable which designed to help solve the problem of determining the number of trains that are suitable and scheduling the train suitably according to the number of trains designated by the system. TO integrates the passenger data from the latest round trip or historical information and forecasts a number of passengers of high-speed trains based on historical data in order to find the optimal number of trains by using a mixed integer programing model. Lastly, the TO system can applies the number of trains to calculate the appropriate train schedule so that the planning cycle is complete. A case study of high-speed railway system in Thailand with 36 trains to satisfy demand of 35,000 passengers/ each direction is conducted. The results show that the proposed system can quickly generate a timetable having an optimal number of train with suitable time interval according to a demand forecasting.

A Versatile OTA Analog Multiplier

Somkiat Piangprantong,Chaiwat Sakul,Kobchai Dejhan,Ittipong Chaisayun 대한전자공학회 2006 ITC-CSCC :International Technical Conference on Ci Vol.2006 No.2

Facebook Users in United Arab Emirates: Underlying the Factors and Demographic Analysis

Somkiat Mansumitrchai,박주희,Candy Lim Chiu 한국마케팅학회 2014 ASIA MARKETING JOURNAL Vol.16 No.1

This study examined the use of Facebook in United Arab Emirates. There were two objectives of this study. The first purpose was to identify the motive for the use of Facebook among people in U.A.E. This study conducted the survey using both qualitative and quantitative methods. One hundred eighty-three working people were used from the survey. Thirty-five questions identified from the interviews were used for the questionnaire design in quantitative method. Factor analysis showed six factors namely usefulness, usage, reliability, making new friends, ethical issue and openness of information. The total variance explained by all the factors was fifty-two percent. This study also examined the demographic variables whether they would play an important role in using the social network site. The study included two more variables, income and married status, which were not frequently examined by previous studies. MANOVA showed statistical significant differences (p < .01) across six factors. ANOVA results showed that gender variable affected only the factor of openness of information. Males were more likely to share their information compared to females. Income variable affected all the factors except the openness of information. The results showed that high-income people had the highest meanscores on three factors (usage, reliability, making new friends) while low-income people had the highest means on usefulness and ethical factors.Marital status had significant effects on usefulness, reliability, and ethical factors. Married people had the low scores on reliability and ethical factors. Lastly, education variable had no effect on all the factors examined.

Review : Molecular Approach for Distal Renal Tubular Acidosis Associated AE1 Mutations

( Somkiat Vasuvattakul ) 대한전해질학회(구 대한전해질,혈압학회) 2010 Electrolytes & Blood Pressure Vol.8 No.1

The molecular approaches to distal renal tubular acidosis (dRTA) associated AE1 mutations Lead us to understand the genetic and pathophysiological aspects of the acidification defects. An unanticipated high value of the urine-blood (U-B) PCO2 after NaHCO3 Loading observed in a case of dRTA and southeast Asian ovalocytosis (SAO) might be from a mistarget of the AE1 to the Luminal membrane of type A intercalated cells. The mutations of the AE1 gene resulted in SAO and also affected renal acidification function. Notwithstanding, after the NH4Cl Loading in 20 individuals with SAO, the acidification in the distal nephron was normal. The presence of both SAO and G701D mutations of AE1 gene would explain the abnormal urinary acidification in the patients with the compound heterozogosity. In terms of the effect of the mutations on trafficking of AE1, truncated kidney isoform (kAE1) of wild-type showed a `dominant-positive effect` in rescuing the recessive mutant kAE1 (S773P or G701D) trafficking to the plasma membrane, in contrast with the dominant mutant kAE1 (R589H) resulting in a `dominantnegative effect` when heterodimerized with the wild-type kAE1. It is notable that the dominant mutants kAE1 (R901X or G609R) expression in MDCK cells clearly results in aberrant surface expression with some mutant protein appearing at the apical membrane. These might result in net bicarbonate secretion and increasing U-B PCO2 in the distal nephron. The molecular physiological and genetic approaches have permitted identification of the molecular defects, predominantly in transporter proteins, and should in turn prompt development of novel therapeutic strategies.

Furfural production by acid hydrolysis and supercritical carbon dioxide extraction from rice husk

Somkiat Ngamprasertsith,Wirungrong Sangarunlert,Pornpote Piumsomboon 한국화학공학회 2007 Korean Journal of Chemical Engineering Vol.24 No.6

companying supercritical CO2 (SC-CO2) extraction. The two-level fractional factorial design method was used to in-vestigate the production process carried out with respect to furfural yield. The process variables are temperature rangeof 373-453 K, pressure 9.1-18.2 MPa, CO2 flow rate 8.3105-1.7104 kg/s (5-10 g/min), sulfuric acid concentration1 to 7 (% wt) and ratio of liquid to solid (L/S) 5 : 1 to 15 : 1 (vol/wt). The results obtained from the experimental designshowed that increasing temperature, pressure, CO2liquid to solid would improve furfural yield. Moreover, furfural production by two-stage process (pre-hydrolysis anddehydration) can improve furfural yield further to be around 90% of theoretical maximum.

Breast Cancer in Lampang, a Province in Northern Thailand: Analysis of 1993-2012 Incidence Data and Future Trends

Lalitwongsa, Somkiat,Pongnikorn, Donsuk,Daoprasert, Karnchana,Sriplung, Hutcha,Bilheem, Surichai Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.18

Background: The recent epidemiologic transition in Thailand, with decreasing incidence of infectious diseases along with increasing rates of chronic conditions, including cancer, is a serious problem for the country. Breast cancer has the highest incidence rates among females throughout Thailand. Lampang is a province in the upper part of Northern Thailand. A study was needed to identify the current burden, and the future trends of breast cancer in upper Northern Thai women. Materials and Methods: Here we used cancer incidence data from the Lampang Cancer Registry to characterize and analyze the local incidence of breast cancer. Joinpoint analysis, age period cohort model and Nordpred package were used to investigate the incidences of breast cancer in the province from 1993 to 2012 and to project future trends from 2013 to 2030. Results: Age-standardized incidence rates (world) of breast cancer in the upper parts of Northern Thailand increased from 16.7 to 26.3 cases per 100,000 female population which is equivalent to an annual percentage change of 2.0-2.8%, according to the method used. Linear drift effects played a role in shaping the increase of incidence. The three projection method suggested that incidence rates would continue to increase in the future with incidence for women aged 50 and above, increasing at a higher rate than for women below the age of 50. Conclusions: The current early detection measures increase detection rates of early disease. Preparation of a budget for treatment facilities and human resources, both in surgical and medical oncology, is essential.

Microsatellite Analysis of the Genetic Diversity and Population Structure in Dairy Goats in Thailand

Seilsuth, Somkiat,Seo, Joo Hee,Kong, Hong Sik,Jeon, Gwang Joo Asian Australasian Association of Animal Productio 2016 Animal Bioscience Vol.29 No.3

The genetic relationships between different populations and breeds of exotic dairy goats in Thailand were studied using 12 microsatellite markers. Blood samples were obtained from 211 goats from Department of Livestock Development breeding and research farms: 29 Anglonubian (AN), 21 Alpine (AP), 23 Jamunapari (JAM), 50 Saanen (SN), and 88 Toggenburg (TG). Five of the 12 microsatellite markers were found to be polymorphic. A mean of 7.40 alleles per locus was found, with a range from 5 (SPS115 and ETH225) to 11 (TGLA122). We found 24, 27, 19, 32, and 24 alleles in the AN, AP, JAM, SN, and TG breeds, respectively; 37 alleles were present in all breeds. The mean number of alleles in each population ranged from 3.2 (ETH225 locus) to 7.6 (TGLA122 locus). Genetic variability within the breeds was moderate as evidenced by the mean expected heterozygosity of 0.539. The average observed heterozygosity across the 5 markers in all breeds was 0.529 with the maximum observed at the BM1818 locus (0.772) and the minimum at the ETH225 locus (0.248). The observed and expected heterozygosity for all breeds for the 5 microsatellite markers ranged from 0.419 to 0.772 and 0.227 to 0.792, respectively. On the basis of their means, the TGLA122 and BM1818 loci were the most suitable markers for distinguishing genetic diversity among the goats. The estimated average $F_{is}$ value for the breeds ranged from -0.044 (ETH225) to 0.180 (SPS115), while the estimated average $F_{st}$ value ranged from 0.021 (SPS115) to 0.104 (ETH10). These results indicated that TGLA122 and BM1818 markers are suitable to be used for aiding conservation and breeding improvement strategies of dairy.

Monitoring of Dry Cutting and Applications of Cutting Fluid for Ball End Milling

Tangjitsitcharoen, Somkiat,Rungruang, Channarong,Laiaddee, Duangta Korean Institute of Industrial Engineers 2010 Industrial Engineeering & Management Systems Vol.9 No.3

For economical and environmental reasons, the aim of this research is hence to monitor the cutting conditions with the dry cutting, the wet cutting, and the mist cutting to obtain the proper cutting condition for the plain carbon steel with the ball end milling based on the consideration of the surface roughness of the machined parts, the life of the cutting tools, the use of the cutting fluids, the density of the particles of cutting fluids dispersed in the working area, and the cost of cutting. The experimentally obtained results of the relation between tool wear and surface roughness, the relation between tool wear and cutting force, and the relation between cutting force and surface roughness are correspondent with the same trend. The phenomena of surface roughness and tool wear can be explained by the in-process cutting forces. The models of the tool wear with the cutting conditions and the cutting times are proposed to estimate the tool cost for the different cooling strategies based on the experimental data using the multiple regression technique. The cutting cost is calculated from the costs of cutting tool and cutting fluid. The mist cutting gives the lowest cutting cost as compared to others. The experimentally obtained proper cutting condition is determined based on the experimental results referring to the criteria.