• Asian-Australasian Journal of Animal Sciences
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• 제23권3호
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• pp.333-339
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• 2010

The objectives of this study were to use the NRC-2001 model and DVE/OEB system to model potential nutrient supply to ruminants and to compare frost damaged (also called "frozen" wheat with normal wheat. Quantitative predictions were made in terms of: i) Truly absorbed rumen synthesized microbial protein in the small intestine; ii) Truly absorbed rumen undegraded feed protein in the small intestine; iii) Endogenous protein in the digestive tract; iv). Total truly absorbed protein in the small intestine; and v). Protein degraded balance. The overall yield losses of the frozen wheat were 24%. Results showed that using the DVE/OEB system to predict the potential nutrient supply, the frozen wheat had similar truly absorbed rumen synthesized microbial protein (65 vs. 66 g/kg DM; p>0.05), tended to have lower truly absorbed rumen undegraded feed protein (39 vs. 53 g/kg DM; p<0.10) and had higher endogenous protein (14 vs. 9 g/kg DM; p<0.05). Total truly absorbed protein in the small intestine was significantly lower (89 vs. 110 g/kg DM, p<0.05) in the frozen wheat. The protein degraded balance was similar and both were negative (-2 vs. -1 g/kg DM). Using the NRC-2001 model to predict the potential nutrient supply, the frozen wheat also had similar truly absorbed rumen synthesized microbial protein (average 56 g/kg DM; p>0.05), tended to have lower truly absorbed rumen undegraded feed protein (35 vs. 48, g/kg DM; p<0.10) and had similar endogenous protein (average 4 g/kg DM; p>0.05). Total truly absorbed protein in the small intestine was significantly lower (95 vs. 108 g/kg DM, p<0.05) in the frozen wheat. The protein degraded balance was not significantly different and both were negative (-16 vs. -19 g/kg DM). In conclusion, both models predict lower protein value and negative protein degraded balance in the frozen wheat. The frost damage to the wheat reduced nutrient content and availability and thus reduced nutrient supply to ruminants by around 12 to 19%.

• 농업과학연구
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• 제45권3호
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• pp.325-353
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• 2018

Agricultural systems in South Asian countries are dominated by smallholder farmers. Additionally, these farmers have limited access to pre- and post-harvest technologies due to their high initial cost. The lack of these technologies in postharvest handling is responsible for 20% to 44% of fruit and vegetable losses. These high losses are largely the result of a generally weak basic postharvest infrastructure for the preservation of products, which avoids damage from improper handling, transportation, packaging, and storage. High postharvest losses of products negatively affect food availability, food security, and nutrition, as the producer is able to sell less of the farm yield and the net availability of these food commodities for consumption is reduced. An underlying cause of these postharvest losses is the limited awareness and knowledge bases of stakeholders (researchers, farmers, governments, non-governmental organizations, and merchants) in the traditional supply chains in which these losses occur. The analysis presented in this paper explores the state of postharvest practice in South Asian countries and discusses options for low-cost postharvest technologies in the region that can support small-scale farmers and provide a viable pathway for supply to the market, joining with modern value chains and bringing about individual and regional reduction in postharvest losses of fruits and vegetables. The improvement of basic and simple low-cost technologies through precise research efforts has the potential to prevent such huge losses of products, and help meet the ever-increasing demand for food in South Asian countries.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2000년도 봄 학술발표회 논문집
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• pp.173-182
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• 2000

To find axial and lateral responses of impact-driven H piles in embankment(SM), the H piles are instrumented with electric strain gages, dynamic load test is performed during driving, and then the damage of strain gages is checked simultaneously. Axially and laterally static load tests are performed on the same piles after one to nine days as well. Then load-settlement behavior is measured. Furthermore, to find the set-up effect in H pile, No. 4, 16, 26, and R6 piles are restriked about 1, 2, and 14 days after driving. As results, ram height and pile capacity obtained from impact driving control method become 80cm and 210.3∼242.3ton, respectively. At 15 days after driving, allowable bearing capacity by CAPWAP analysis, which 2.5 of the factor of safety is applied for ultimate bearing capacity, increases 10.8%. Ultimate bearing capacity obtained from axially static load test is 306∼338ton. This capacity is 68.5∼75.7% at yield force of pile material and is 4∼4.5 times of design load. Allowable bearing capacity using 2 of the factor of safety is 153∼169ton. Initial stiffness response of the pile is 27.5ton/mm. As the lateral load increases, the horizontal load-settlement behaves linearly to which the lateral load reaches up to 17ton. This reason is filled with sand in the cavity formed between flange and web during pile driving. As the result of reading with electric strain gages, flange material of pile is yielded at 19ton in horizontal load. Thus allowable load of this pile material is 9.5ton when the factor of safety is 2.0. Allowable lateral displacement of this pile corresponding to this load is 23∼36mm in embankment.

• Toxicological Research
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• 제34권4호
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• pp.281-290
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• 2018

Exposure to chemical agents is an inevitable consequence of modern society; some of these agents are hazardous to human health. The effects of chemical carcinogens are of great concern in many countries, and international organizations, such as the World Health Organization, have established guidelines for the regulation of these chemicals. Carcinogens are currently categorized into two classes, genotoxic and non-genotoxic carcinogens, which are subject to different regulatory policies. Genotoxic carcinogens are chemicals that exert carcinogenicity via the induction of mutations. Owing to their DNA interaction properties, there is thought to be no safe exposure threshold or dose. Genotoxic carcinogens are regulated under the assumption that they pose a cancer risk for humans, even at very low doses. In contrast, non-genotoxic carcinogens, which induce cancer through mechanisms other than mutations, such as hormonal effects, cytotoxicity, cell proliferation, or epigenetic changes, are thought to have a safe exposure threshold or dose; thus, their use in society is permitted unless the exposure or intake level would exceed the threshold. Genotoxicity assays are an important method to distinguish the two classes of carcinogens. However, some carcinogens have negative results in in vitro bacterial mutation assays, but yield positive results in the in vivo transgenic rodent gene mutation assay. Non-DNA damage, such as spindle poison or topoisomerase inhibition, often leads to positive results in cytogenetic genotoxicity assays such as the chromosome aberration assay or the micronucleus assay. Therefore, mechanistic considerations of tumor induction, based on the results of the genotoxicity assays, are necessary to distinguish genotoxic and non-genotoxic carcinogens. In this review, the concept of threshold of toxicological concern is introduced and the potential risk from multiple exposures to low doses of genotoxic carcinogens is also discussed.

• 한국강구조학회 논문집
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• 제21권5호
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• pp.461-470
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• 2009

기둥은 축하중과 지진하중에 저항하는 주부재로서 구조물에서 가장 중요한 부재중의 하나이다. 이러한 기둥은 화재 시 고온에 의해 그 성능이 저하되어 전체 구조물계에 심각한 균열을 초래할 수 있으며, 구조물의 붕괴로도 이어질 수 있다. 본 연구에서는 새로운 형식의 기둥인 내부구속 중공 콘크리트 충전강관 기둥 (ICH CFT column; Internally Confined Hollow Concrete Filled Tube column)의 내화 성능이 연구되어져 있지 않기 때문에 건축물에 적용을 하여 기준에 맞는 기둥을 만들기 위해서는 내화 성능 평가가 필요하다. 본 기둥은 콘크리트 충전 강관 기둥 (CFT column; Concrete Filled Tube column)과 같이 외부 강관에 의해 콘크리트가 구속되어 기둥의 성능을 발휘하므로, 외부 강관의 항복 여부가 전체 기둥의 강도를 결정하게 될 것이다. 그래서 본 연구에서는 화재에 의한 기둥의 온도 변화에 따른 ICH CFT 기둥의 강도를 콘크리트의 구속효과와 재료비선형성을 고려하여 해석을 수행하였고, 또한 기둥의 중공비, 외부강관의 두께, 콘크리트의 강도를 매개 변수로 선정하여 기둥의 내화 성능을 평가하였으며, 해석에는 범용 프로그램과 전용 프로그램을 병행하여 사용하였다.

• 한국균학회지
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• 18권2호
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• pp.89-96
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• 1990

Thiabendazole이 느타리버섯 재배에서 발생하는 푸른곰광이병에 방제약제로서의 가능성을 조사한바 다음과 같은 결론을 얻었다. 1. 한천배지상에서 원제농도가 50ppm 처리구에서는 ASI 2001, 2072, 2016, 100 ppm에서는 ASI 2018, 500 ppm에서는 ASI 2070호가 균사생장이 억제되었다. 2. 볏짚의 침수시 처리된 약제의 농도 중 0.2g/1000ml 이상의 처리구에서 느타리버섯 균사생장이 억제되기 시작하였다. 3. 공시약제의 모든 처리는 푸른곰광이 병원균의 처리구와 푸른곰팡이 병원균과 느타리버섯균의 혼합처리구에서도 컬럼의 하단부에 푸른곰장이병의 발생을 발견할 수 없었다. 4. 살균 전 균상표면에 약제를 농도별로 표면살포한 결과 방제효과는 $2g/m^2$ 과 $5g/m^2$의 처리구에서 병해가 발생하지 않았으며, 수량성은 $5g/m^2$ 처리구에서 가장 수량이 높았다.

• 한국염색가공학회지
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• 제6권2호
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• pp.55-62
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• 1994

The mend for fabric products has been increased remarkably with increasing population, housings, mutistory buildings,...and etc. during the last two decades. However, since fabrics are highly combustible and can produce toxic gases during the combution, fabric products can result in serious human injury as well as financial damage. Acknowledged by this, a new phosphorus based flame retardant suitable for PET fabric has been synthesized by making use of the reaction of diphenyl chloro phosphate and hexamethylenediamine. Since the starting meterials are relatively cheap and the yield of this reaction is high (more than 90%), this reaction seems to be very effective as wall as very economic. By analyzing various spectrophotometric analysis data such as NMR, FT-IR, and Mass, this new flame retardant is identified to be N,N’-Bis(diphenyl chlorophosphoro)diamino hexane. In the mean time, DSC measurement has shown that the melting point and the boiling point of this material are around 115$^{\circ}C$ and around 40$0^{\circ}C$, respectively. The flame retardancy test done on the PET fabric processed by this flame retardant have shown excellent in times of flame contact, times of flame contact for washable. The most economical finishing condition estimated 10% in concentration of BDPDH, Moreover, it has been also found that the drape stiffness of the PET fiber processed by the flame retartant is changed very litter compared to the unprocessed original PET fabrics. Judging from this, the potential of this new phosphrdus based compond as a flame retardant for PET fabric seems to be high.

• Preventive Nutrition and Food Science
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• 제16권2호
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• pp.127-134
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• 2011

The purpose of this study was to purify antioxidant substances from steamed squid extract (SSE). The yield of SSE was 8% by dry weight. The approximate compositions of SSE proteins, lipids, moisture, carbohydrate and ash were 64.95%, 1.69%, 7.23%, 4.44% and 21.69%, respectively. The major amino acids in SSE were taurine (29.17%), glycine (20.33%), alanine (12.51%), and glutamic acid (9.83%). Antioxidant activities were evaluated using 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical scavenging activity, which was measured as 24.7% at 1.0 mg/mL. Four SSE fractions were isolated by Sephadex G-25 gel chromatography; the F2 fraction showed the highest DPPH radical scavenging activity. The F2 fraction was separated by reverse-phase high performance liquid chromatography (HPLC) using an octadecylsilane (ODS) column, yielding a purified antioxidant substance with a DPPH radical scavenging activity of 64.41% at 1.0 mg/mL, representing a 2.64-fold increase in the scavenging activity of SSE purified by the 3-step procedure. The amino acid compositions showed that purified SSE was rich in taurine, glycine, glutamic acid and alanine. The purified SSE significantly elevated 2',7'-dichlorodihydrofluororescein diacetate (DCFH-DA) fluorescence probe, which confirms its effective radical scavenging potential in cellular ROS. In addition, the SSE significantly inhibited oxidative damage of purified genomic DNA. These results suggest that a purified antioxidant substance from SSE can be used as a potential natural compound-based antioxidant in the functional food and pharmaceutical industries.

• 한국수산과학회지
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• 제36권4호
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• pp.409-416
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• 2003

Marine populations are maintained through the processes of spawning, growth, recruitment, natural death and fishing in a marine ecosystem. Based upon each of these processes, a quantitative population dynamic model was developed to estimate damages in fishery production due to accidents in a fishing ground. This model was applied for the abalone culture grounds in Korean waters. Three components of damages were identified in the ecosystem of the abalone culture grounds, namely, physical damages in the substratum of the fishing ground, biological damages in the structure and function of the ecosystem, and damages in fishery production. Considering these three components the processes and durations of damages in fishery production were determined. Because the abalone population is composed of multiple year classes, damages influence all the year classes in the population, when they occur The model developed in this study is: $$y=(n_{\lambda}+1){\times}Y_E\;-\;\sum\limits^{n_\lambda-n_c}_{l=0}\;y_{n_c/i}$$ where, y is the expected damages in fishery production during the period of restoration of the damaged abalony population, $Y_E$ is the annual equilibrium yield, $n_{\lambda}$ is the maximum age in the population, $t_s$ is the year of damage occurrence, $n_c$ is the age at recruitment, and $\sum\limits^{n_\lambda-n_c}_{l=0}\;y\;_{n_c/i}$ is total expected lifetime catch of year classes which were recruited during the restoration period.

• 한국환경과학회지
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• 제27권8호
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• pp.641-650
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• 2018

Paddy-upland rotation system is one of the important cropping system for improving soil quality and crop productivity. we conducted to investigate the effect of paddy-upland rotation system on soil properties and crop productivity in reclaimed tidal land. The paddy-upland rotation could be effective to conserve soil water contents and prevent from salt damage when cultivating upland crops. The first two years of maize cultivation after rice cultivation could be effective to secure stable production. However, in case of soybean crop, the rotation effect might be lower than that of maize. In the first year, the yield of soybean was 214 kg/10a. In the second and third year, the yields of soybean decreased consecutively to 152, 123 kg/10a respectively. In this paper, it would be suggested that maize be cultivated for up to two years and soybean be cultivated for one year after rice crop grown in reclaimed tidal land. This study could be provide basic data of the physico-chemical properties applicable to paddy-upland rotation system at reclaimed tidal lands.