• Journal of Microbiology and Biotechnology
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• 제19권10호
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• pp.1127-1134
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• 2009

Escherichia coli excretes acetate during aerobic growth on glycolytic carbon sources, which has been explained as an overflow metabolism when the carbon flux into the cell exceeds the capacity of central metabolic pathways. Nonacetogenic growth of E. coli on gluconeogenic carbon sources like succinate or in carbon-limited slow growth conditions is believed an evidence for the explanation. However, we found that a strain defected in the acs (acetyl Co-A synthetase) gene, the product of which is involved in scavenging acetate, accumulated acetate even in succinate medium and in carbon-limited low growth rate condition, where as its isogenic parental strain did not. The acs promoter was inducible in noncatabolite repression condition, whereas the expression of the ackA-pta operon encoding acetate kinase and phosphotransacetylase for acetate synthesis was constitutive. Results in this study suggest that E. coli excretes and scavenges acetate simultaneously in the carbon-limited low growth condition and in nonacetogenic carbon source, and the activity of the acetate consumption pathway directly affects the accumulation level of acetate in the culture broth.

• 한국수산과학회지
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• 제43권5호
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• pp.489-494
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• 2010

The nutritional demand of oyster larva (Crassostrea gigas) were investigated to determine the optimal culture conditions and improve micro-algae utilization. Changes in nutrients and shell growth were examined in fed and 96-h (48 h in late umbone stage) oysters at four larval stages. Shell growth increased significantly in D shape larvae, regardless of feeding variations. No growth was observed in starved larvae, except in shell length of umbone (to 11.9 ${\mu}m$). Fed larvae showed significant growth in all development stages (P < 0.05). During starvation, lipids were most significantly decreased in all larval stages (by 76.8%, 68.3%, 76.3%, and 40.3%, respectively), followed by protein (41.1%, 31.1%, 33.1%, 16.7%) and nitrogen-free extracts (40.8%, 24.3%, 36.9%, 20.1%), Gross energy (kcal/g) consumption in each larval stage was 49.6%, 35.1%, 39.1%, and 20.4%, respectively. Our results indicate that lipids are the most important energy source during the early larval development stages of C. gigas.

• Journal of Preventive Veterinary Medicine
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• 제42권4호
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• pp.143-147
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• 2018

The present study aimed to develop growth prediction models of Listeria monocytogenes in processed meat products, such as mixed pressed hams, to perform accurate microbial risk assessments. Considering cold storage temperatures and the amount of time in the stages of consumption after opening, the growth of L. monocytogenes was determined as a function of temperature at 0, 5, 10, and $15^{\circ}C$, and time at 0, 1, 3, 6, 8, 10, 15, 20, 25, and 30 days. Based on the results of these measurements, a Baranyi model using the primary model was developed. The input parameters of the Baranyi equation in the variable temperature for polynomial regression as a secondary model were developed: $SGR=0.1715+0.0199T+0.0012T^2$, $LT=5.5730-0.3215T+0.0051T^2$ with $R^2$ values 0.9972 and 0.9772, respectively. The RMSE (Root mean squared error), $B_f$ (bias factor), and $A_f$ (accuracy factor) on the growth prediction model were determined to be 0.30, 0.72, and 1.50 in SGR (specific growth rate), and 0.10, 0.84, and 1.35 in LT (lag time), respectively. Therefore, the model developed in this study can be used to determine microorganism growth in the stages of consumption of mixed pressed hams and has potential in microbial risk assessments (MRAs).

• The Journal of Asian Finance, Economics and Business
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• 제2권2호
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• pp.5-12
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• 2015

The authors calculate the long-term predictability of GDP, domestic demand, investment, and net exports for Guangdong province, P.R. China from 2000 to 2013. A vector autoregressive (VAR) model with quarterly data for this period is first co-integrated then the Granger causality test is applied to empirically assess the relationships among gross domestic product (GDP), consumption, investment, and net exports. There is a strong causality effect between investment and net exports in Guangdong province. However, the variance decomposition results indicate that exports respond to foreign shocks rather than domestic ones, making their impact on the Guangdong economy to predict. Results show the stimulating effect of domestic demand on GDP is larger than the stimulating effect of net exports and much larger than even the stimulating effect of investment. The analysis suggests that there are dynamic influences with various levels of persistence between GDP, consumption, investment, and net exports. Macroeconomic policy adjustments are urgently required to expand domestic demand and thereby stimulate economic growth in Guangdong province.

• 스마트미디어저널
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• 제12권11호
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• pp.18-26
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• 2023

빌딩에너지관리시스템(BEMS: Building Energy Management System)은 생산 및 소비되는 에너지를 효율적으로 관리하는 시스템이다. 그러나 건물 내 전력소비는 물리적인 특성상으로 인해 생산 및 소비가 일정하지 않아 안정적인 전력 공급이 필수적이다. 이에 따라 건물의 안정적인 전력 공급을 위해서는 정확한 건물 내 전력 소비 예측이 중요하다. 최근에는 시계열분석, 통계분석, 인공지능 등 다양한 방법을 이용하여 전력소비예측에 관한 연구가 진행되고 있다. 본 논문은 Prophet 모델의 장점과 단점을 분석하여 장점인 growth, seasonality, holidays를 선택하였고, Prophet 모델의 단점인 데이터의 복잡성과 외부변수(기후 데이터)의 제한성을 해결하기 위하여 GRU을 조합하여 단기(2일) 및 중기(7일, 15일, 30일) 전력소비량 예측 알고리즘을 제안한다. 실험결과, 제안한 방법은 기존 GRU 및 Prophet 모델보다 성능이 우수하였다.

• 한국조리학회지
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• 제13권3호
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• pp.293-307
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• 2007

This article was to provide information enabling us to respond effectively to the well being market which has great potential of growth by studying well-being consumption behaviour according to the lifestyles of dining-out customers and to find out how their lifestyles have influence on well-being by investigating their patterns according to demographical characteristics of dining-out customers who play key role in consumption and will have great purchasing power in food service industry. First, factor analysis of variation of lifestyle, 6 factors are named conscious style, realistic style, self-regard style, health-focusing style, changeable style, and fashion-sensitive style. Second, factor analysis of well-being consumption behaviour, 5 factors over eigen 1 are selected and used in a research and they are named healthful food principle, physical health principle, mental health principle, confidence principle, and old-age planning principle. Analysis result reveals that there exists significant relationship between lifestyle and well-being consumption behaviour.

• 한국진공학회지
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• 제1권1호
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• pp.153-161
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• 1992

A plasma has been used in a high vaccum, cold wall reactor for low temperature deposition of C54 TiSi2 and for in-situ surface cleaning prior to silicide deposition. SiH4 and TiCl4 were used as the silicon and titanium sources, respectively. The deposited films had low resistivities in the range of 15~25 uohm-cm. The investigation of the experimental variables' effects on the growth of silicide and its concomitant silicon consumption revealed that and were the dominant species for silicide formation and the primary factors in silicon consumption were gas composition ratio and temperature. Increasing silane flow rate from 6 to 9 sccm decreased silicon consumption from 1500 A/min to less than 30 A/min. Furthermore, decreasing the temperature from 650 to $590^{\circ}C$ achieved blanket silicide deposition with no silicon consumption. A kinetic model of silicon consumption is proposed to understand the fundamental mechanism responsible for the dependence of silicon consumption on SiH4 flow rate.

• Asian-Australasian Journal of Animal Sciences
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• 제31권7호
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• pp.984-991
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• 2018

The beef industry is an important part of livestock and meat production in China. China ranks third in the world for beef production. With the rapid development of the Chinese economy, beef consumption has grown rapidly, and beef consumption has been increasing with rising per capita gross domestic production. However, the domestic beef industry in China has not been able to keep pace with growth in consumption, making China a net importer of beef from other countries. Moreover, the volume of production has increased little despite rising demand. The slowing of growth in beef production in recent years has led to a sharp rise in beef prices. Domestic beef production and consumption is restricted by a shortage of beef cattle inventory. The Chinese beef industry is facing many technical problems including transformation of traditional practices, feeding and management systems, and genetic improvement of cattle breeds. The long-term, sustainable development of the Chinese beef industry is an important issue for China.

• 에너지공학
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• 제28권2호
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• pp.1-17
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• 2019

본 논문은 한국을 대상으로 1976년부터 2014년까지 경제성장, 전력소비, $CO_2$ 배출과 외국인직접투자(FDI) 유입 간 인과관계를 단위근 검정, 공적분 검정, 벡터오차수정모형(VECM)을 적용하여 분석한다. 분석의 결과는 다음과 같다. 첫째, 경제성장과 전력소비 간에는 장기적으로 양방향의 인과관계가 나타나, 상호관계를 고려하지 않은 전력소비절약정책은 경제성장에 부정적인 영향을 미칠 수 있는 것으로 분석되었다. 둘째, $CO_2$ 배출은 경제성장에 대한 단방향의 장 단기적인 인과관계와 전력소비에 대한 단방향의 장기적인 인과관계를 나타내, $CO_2$ 배출 감축정책이 경제성장과 전력소비에 부정적인 영향을 미칠 수 있는 것으로 분석되었다. 셋째, FDI 유입은 경제성장에 대해 단방향의 장기적인 인과관계를, 전력소비에 대해 단방향의 장 단기적인 인과관계를 나타내, FDI 유입이 상대적으로 저렴한 전력소비비용에 기반을 둔 것으로 분석되었다. 반면, FDI 유입은 $CO_2$ 배출에 대해서는 인과관계가 없는 것으로 나타났는데, 이는 서비스 산업 중심으로 이루어지는 FDI의 특성에 따른 것으로 분석되었다. 이러한 네 변수 간 인과관계들을 고려할 때, 능동적인 전력수요관리를 위한 기술개발의 확대와 화석연료에서 신재생에너지로의 신중한 전환을 위한 정책 등이 모색되어야 한다. 또한 FDI 유치의 증대에 대응하여 에너지절약시설 투자 및 설치를 통해 전력소비 감축을 유도할 필요가 있다.

• Asian Journal of Atmospheric Environment
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• 제12권1호
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• pp.30-36
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• 2018

This study investigates the relationship between economic growth, energy consumption, trade openness, population density, and carbon dioxide ($CO_2$) emissions in Bangladesh for the period of 1975 to 2013. It applies the Autoregressive Distributed Lag (ARDL) bounds testing approach to cointegration for establishing the existence of a long-run relationship. The bounds tests suggest that the variables of interest are bound together in the long-run when $CO_2$ emissions is the dependent variable. The results indicate that energy consumption has statistically significant positive effect on $CO_2$ emissions both in the short-run and long-run. The effect of population density is significant in long-run, but not in short-run. The estimated coefficients for economic growth and trade liberalization are negative and insignificant both in short-run and long-run. The paper suggests that the government of Bangladesh should undertake the policy actions to develop alternative energy sources which would not emit much $CO_2$.