• 센서학회지
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• 제26권4호
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• pp.251-258
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• 2017

According to recent studies by scientists about how to search for food, homes and the mates, it is found that the gradient information plays a key role. From cells to insects and large animals, they mostly either have special sensing organism or use a strategy to measure the gradient. Use of a perturbation as an additional input is introduced for sensor signal processing in order to get the gradient information. Different from typical approach, which calculates the gradient from differentiation, the proposed processing is done by a form of integration, thus it is very robust to noise. Discrete time domain analyses are given for one, two and three input functions for the estimation of the gradients. The amplitude and the frequency of the perturbation are two important parameters for this approach. A quantitative index to measure the effects of the amplitude is developed based on the linear regression analysis. The frequency of the perturbation is to be selected high enough to finish one period of the perturbation before the property is changed significantly with respect to time. Another quantitative index is proposed for guiding the selection of the frequency.

• 수산해양기술연구
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• 제47권2호
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• pp.99-107
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• 2011

The relationships among long-term variation in catches of Spanish mackerel (Scomberomorus niphonius) and main food organism such as common mackerel (Scomber japonicus), anchovy (Engraulis japonicus), and oceanic condition in Korean waters were analyzed using 40 years of time-series data from 1971－2010. In the 1990s, oceanic conditions around the Korean peninsula shifted to a warmer regime with higher SST (sea surface temperature). The total catch of Spanish mackerel in Korean waters increased dramatically since the early 2000s, and main fishing ground form into South Sea in winter season from December to January. From the results of correlation analysis, we found a significant relationship between the Spanish mackerel catch and environmental factor such as SST, common mackerel and anchovy catch in Korean waters.

• Journal of Dairy Science and Biotechnology
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• 제34권4호
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• pp.271-278
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• 2016

The main purpose of milk heat-treatment is to improve milk safety for consumer by destroying foodborne pathogens. Secondly, heat-treatment of milk is to increase maintaining milk quality by inactivating spoilage microorganisms and enzymes. Pasteurization is defined by the International Dairy Federation (IDF, 1986) as a process applied with the aim of avoiding public health hazards arising from pathogens associated with milk, by heat treatment which is consistent with minimal chemical, physical and organoleptic changes in the product. Milk pasteurization were adjusted to $63{\sim}65^{\circ}C$ for 30 minutes (Low temperature long time, LTLT) or $72{\sim}75^{\circ}C$ for 15 seconds (High temperature short time, HTST) to inactivate the pathogens such as Mycobacterium bovis, the organism responsible for tuberculosis. Ultra-high temperature processing (UHT) sterilizes food by heating it above $135^{\circ}C$ ($275^{\circ}F$) - the temperature required to destroy the all microorganisms and spores in milk - for few seconds. The first LTLT system (batch pasteurization) was introduced in Germany in 1895 and in the USA in 1907. Then, HTST continuous processes were developed between 1920 and 1927. UHT milk was first developed in the 1960s and became generally available for consumption in the 1970s. At present, UHT is most commonly used in milk production.

• 한국조명전기설비학회지:조명전기설비
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• 제9권2호
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• pp.23-28
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• 1995

원적외선이 생체에 미치는 영향을 관찰하기 위하여 포유동물인 흰쥐를 대상으로 실험을 실시하였다. 원적외선이 발생되도록 특수설계된 장치를 이용하여 흰쥐의 생리상태, 생식활동 및 생존능력에 변화와 차이를 유발시키는지의 여부를 관찰한 결과, 물과 먹이의 소모량, 체중, 수태율, 출산율 및 새끼의 성비(性比)에 있어서 자연상태와 동일하였기 때문에 원적외선이 하등의 유해작용을 발생시키지 않는다는 사실을 확인하였고, 가혹한 실험상황에서 흰쥐의 생존력이 자연상태의 흰쥐보다 약 122% 증가한다는 결과를 얻으므로써 원적외선이 흰쥐의 체력과 지구력을 증강시키는 역할을 한다는 새로운 사실을 관찰하였다.

• 한국조경학회지
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• 제18권2호
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• pp.111-125
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• 1990

Korea is a nation with poor natural resources. There is a greats need to save resources that are running out in fast face. The purpose of this thesis is to bind the means to save rosources in housing site, especially in highrise apartment. The reason why the high-rise apartments are chosen as a case is 7hat the high-rise is becoming the major form of dwelling in most urban areas. As a tool of saving the ecological way is chosen because ecological energy is free, clean and unlimited. The resources to be saved are divided into two categories, namely energy and non - energy resources as water, land and food. The contents of the thesis are comprised of 4 chapters. The early chaspters are devoted to the understanding of the ecosystem and problems of current energy consumption in the apartment. It is fellowed by the introduction of the hypothesis that can possibly save reouruces. The hypothesis are then transformed into the actual theories through verification, to be established as the new techniques of the site planning. The ecosystem is the functional relationship between the living organisms and their physical surroundings. The living organisms are the plants that produce, animals that consume and bacterias that decompose. They live in the environment which consists of the three worlds of atmosphere, hydrosphere and lithosphere. The whole system is activated by the solar energy that turns the inorganic mallet- into the living organism and back to the inorganic. It is the recycling principle of the ecosystem. The elements of ecosystem that fan be unilimited as the tools of resources -saving are the sun, wind, water, soil, plant and waste. They are unlimited sources of energy. free of pollution and cheap in price. Each of these ecological elements Provide the opportunities that can save the heating fuel, air conditioning energy, water resource, land and food. The ecological approch should be pursued actively in this age of short resources and growing pollution. In the scale of total energy consumption the housing takes the second position next to the industrial use. It is followed by the transportation which shows for less consumption than former two.

• 한국식품위생안전성학회지
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• 제14권4호
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• pp.352-357
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• 1999

우유에 쑥 추출물을 수준별로 첨가하고 2종(Lac. bulgaricus와 Str. themophilus)의 젖산균을 단독 또는 혼합 배양하여 호상 요구르트를 만들고, 쑥 추출물의 첨가가 젖산균의 생육과 산 생성 및 요구르트의 관능적 특성에 미치는 영향을 조사하였다. 쑥 추출물의 첨가로 인해 요구르트의 젖산균 증식과 산 생성이 대조군(우유 요구르트)보다 현저하게 촉진되었으며, 특히 Lac. bulgaricus와 Str. themophilus를 혼합 배양한 경우에 산 생성이 가장 우수하여 산도는 1.921%이었고, Lac. bulgaricus를 단독 배양한 경우에 생균수가 가장 높아 7.72$\times$$10^{8}$ CFU/ml를 나타내었다. 관능검사 결과를 보면 쑥 추출물 첨가 요구르트의 경우 대조군에 비해 색깔, 향기, 맛, 조직감, 후미 및 전체적인 기호도 등 관능성이 대체로 우수한 것으로 나타났으며, Lac. bulgaricus를 단독 균주로 하여 쑥 추출물을 5% 첨가하여 제조한 요구르트의 선호도가 가장 높게 평가되었다. 이상의 결과로 볼 때 우유에 쑥 추출물의 첨가는 기호성이 높고 식품 영양학적으로 우수하여 그 상품적 가치가 인정되는 새로운 요구르트의 제조가 가능할 것으로 생각된다.

• 대한수의학회지
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• 제48권3호
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• pp.275-285
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• 2008

Antimicrobial drugs are widely used in poultry industry as growth promoters or to control infectious diseases. However, this practice is reported to have caused high resistance to antimicrobial drugs in normal chicken flora and pathogens. Antimicrobial resistance to Escherichia coli (E. coli) from chicken has been mainly reported in normal flora, but rare in pathogenic organism in Korea, recently. Therefore, this study was conducted to investigate prevalence of antimicrobials resistance, transfer of R plasmid, and association between antimicrobial drug resistance and O serotype of 203 pathogenic E. coli from poultry in Korea during the period from April 2003 to December 2005. These isolates showed a high resistance to tetracycline (Tc, 93.6%), nalidixic acid (Na, 92.6%), streptomycin (Sm, 81.8%), ampicillin (Ap, 77.3%), ciprofloxacin (Ci, 70.9%), sulfisoxazole (Su, 66.5%), and trimethoprim (Tp, 58.1%). Two hundred-one (99.0%) of the isolates were resistant to one or more drugs. They showed 57 different resistant patterns, and the most prevalent resistant pattern among them was Tc, Sin, Su, Ap, Tp, Ci, Na. Sixty-eight (33.8%) of the isolates transferred all or a part of their antimicrobial resistant pattern to the recipient strain by R plasmid. The most common antimicrobial resistant pattern was Tc, Sm, Su, Ap, Tp, Ci, Na in serotype O78, O88 and O15, respectively. These results exhibit high individual and multiple resistance to antimicrobials of pathogenic E. coli from poultry in Korea. They also suggest the needs for surveillance to monitor antimicrobial resistance in pathogenic bacteria that can be potentially transmitted to humans from food animals and to regulate the abuse of antimicrobials on food-producing animals in Korea.

• KSBB Journal
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• 제27권2호
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• pp.91-96
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• 2012

In this study, a newly synthesized thiazolidinedione derivative, TD49 with a highly selective algicide to red tide, was examined in order to evaluate the bioconcentration on aquatic organisms of coast. BAF (accumulation of TD49 by aquatic food chain) and BCF (accumulation of TD49 by sea water) were examined employing the shrimp (Fenneropenaeus chinensis) as the feed organism, and the olive flounder Paralichthys olivaceus as a consumer in marine ecosystem. Bioconcentration degree in sea water showed that the order in P. olivaceus was viscera > gill > muscle. The average BCF values of TD49 were 67.70, 63.32 and 20.25 at viscera, gill and muscle, respectively. Bioaccumulation degree using feed showed that the order in the organs of P. olivaceus was viscera > gill > muscle. The average BAF values of TD49 were 175.89, 114.88 and 32.59 at viscera, gill and muscle, respectively. When compared with two results, the accumulation by the food and water was higher than that by water. After the elimination experiment in sea water, the TD49 concentration was 2.81 nmole/g in the viscera and were not found in the gill and the muscle. More than 50% of the accumulated TD49 were eliminated from viscera in 7 days and all the accumulated TD49 were eliminated from gill and muscle in 7 days. On the other hand, the octanol/water partition coefficient (log $K_{ow}$) was measured to be 3.66 and experimental BCF of this study was 67.7.

• 한국양식학회지
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• 제11권1호
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• pp.91-97
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• 1998

이 연구에서는 해산어의 종묘 생산에 필요한 대량 배양용 로티퍼, Brachionus rotundiformis의 종 보존 방법으로서 무균 로티퍼의 이용을 검토했다. 로티퍼는 개량형 항생제 혼합액 AM9을 사용하여 무균 처리한후, 무균 Nannochloropsis oculata를 먹이로 공급하여 연속 유지 배양했다. 각각 다른 시기의 3회 (trial 1, 2 and 3)에 걸친 로티퍼 배양결과, 무균 배양 (axenic culture)에서는 비교적 안정적인 증식을 보인 반면, 유균 배양 (non-axenic culture)에서 로티퍼의 증식은 불안정적으로 각 시기에 따라서 심한 증식의 차이가 관찰되었다. 이 결과는 유균 배양에서 로티퍼의 증식에 직접적으로 악영향을 미치는 박테리아가 무균 처리과정을 통해서 제거되었음을 증명한다. 로티퍼 무균 배양 방법의 일반화 또는 대량 배양용 로티퍼의 씨앗으로서의 무균 로티퍼의 이용은 로티퍼의 안정 배양은 물론 유용 수산 생물의 대량 폐사를 일으키는 원인 생물을 사전에 제거할 수 있는 유효한 방법이 될 수 있다고 생각된다.

• 한국양식학회지
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• 제11권1호
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• pp.113-118
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• 1998

Tigriopus japonicus를 대량생산하는데 필요한 기초적인 자료를 얻기 위해 무균 배양을 통한 nauplius 유생 단계와 성체의 식성에 대하여 조사하였다. 무균 상태의 성체는 먹이로 공급한 RT 박테리아주를 적극적으로 이용하여, 순조로운 증식을 보였다. 먹이로 공급한 RT 균주의 증식은 포식자 T. japonicus의 섭식에 의해서 그 증식이 크게 억제되었다. RT 균주만을 먹이로 배양한 T. japonicus의 성체가 가지고 있는 난낭안에는 oil bead로 충만해 있었다. 그러나, 무균 상태의 N. oculata만을 먹이로 공급한 경우에는 oil bead를 전혀 관찰할 수 없었다. 무균 조건의 nauplius 유생의 경우에는 먹이로서 공급한 RT 박테리아주를 적극적으로 이용하여 RT 박테리아주의 증식을 크게 억제하였다. 이 결과는 지금까지 T. japonicus가 잡식성인 것만으로 알려진 것과는 달리, 최소한 섭식기구가 미발달된 nauplius의 초기 유생은 사육수중에 세균이 존재하지 않는 경우에는 정상적인 발생이 불가능하였다. 즉, 부화 직후 또는 발생 초기의 T. japonicus의 nauplius 유생은 박테리아식성 (bacterivorous)이었다.