• Feed Journal
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• v.3 no.6 s.22
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• pp.54-59
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• 2005

양축농가(단위 동물 기준)의 생산비 가운데 사료가 차지하는 비율은 통상 60$\%$정도다. 이러한 높은 비율의 사료비를 절약하는 방법으로는 지금까지 주로 사료의 허실을 방지하는 것으로 가장 많이 고려되어왔다. 하지만 무더운 여름철엔 높은 온도와 습도등으로 인해, 자칫 사료의 질이 떨어지기 쉽고 성장능력이 감소하고 생산성도 떨어지기쉽다. 하지만 이는 눈에 뚜렷하게 보이지 않는다는 이유로 거의 무시되어 왔다. 따라서 이 글에서는 무더운 여름철에 사료에서 어떤 문제점이 발생하며, 그 해결방안은 무엇인지를 살펴 보기로 한다.

• Journal of Korean Society of Transportation
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• v.28 no.5
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• pp.43-54
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• 2010

In order to improve the existing evaluation system of bus services and gain more reasonable analysis outputs, the authors evaluate the efficiency of 113 arterial bus routes in Seoul in 2009 using a modified BCC model considering not only desirable outputs but also undesirable outputs. Each Decision Making Unit (DMU) is assumed to use inputs such as possession costs, operating costs, the ratios of median bus stops overlapped route lengths to produce estimates of desirable outputs (the number of passengers and service satisfaction score) and undesirable outputs (CO2 emissions). According to the analysis, the modified BCC model considering both desirable outputs and undesirable outputs shows more appropriate results. DMUs would be more efficient on average to reduce nearly 10% of the 3 inputs (possession costs, operating costs, and overlapped route lengths) and increase by about 160% the ratios of median bus stops. Also, a Tobit regression analysis is conducted to identify the most effective variables for maximum efficiency and discover that the variable of possession costs and the ratios of median bus stops are statistically significant.

• Journal of the Korea Convergence Society
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• v.13 no.5
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• pp.483-488
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• 2022

This study was conducted to compare of dietary behaviors of young and temporary workers with older and permanent workers of single-person households. A questionnaire survey was conducted by purposive quota sampling(n=566) by age groups(20~59 years old) and status of workers(temporary workers, permanent workers and business owners). Compared to other age groups, 20s had lower average monthly income and cost of eating-out, and they rarely cooked at home and mainly bought food and groceries at convenience stores(p<0.001). This pattern was similar to temporary workers compare to other groups. This study will be meaningful as a basic data for creating a healthy living environment for temporary workers and 20s of single-person households.

• Journal of the East Asian Society of Dietary Life
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• v.23 no.3
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• pp.297-310
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• 2013

This study was performed to investigate relationships among night eating and nutrient intakes status in university students. A total of 271 subjects (male=155, female=116) were divided by using 3-days food record method according to the percentage of energy from night eating: non-night eating, <25% night-eating and ${\geq}25$ night-eating group. There were no significant differences in age, height, weight, percent body fat and BMI among the groups. The proportion of morning anorexia and insomnia was below 2% and 10%, and no differences were observed among the groups by percentage of energy from night eating. In the male subjects, the intakes of energy in the '${\geq}25$ night-eating group' was significantly higher than those of the other groups; whereas, the nutrient density (ND, nutrient intakes per 1,000 kcal) and INQ (index of nutritional quality) of vitamin $B_1$, vitamin $B_2$, vitamin C, calcium and iron in the '${\geq}25$ night-eating group' was significantly lower than those of the other groups. In the female subjects, the intakes of energy in the '<25 night-eating group' was significantly higher than that of the 'non-night eating group'. And the ND and INQ of vitamin C in the '<25 night-eating group' was significantly higher than those of the 'non-night eating group'. In addition, within the male subjects, the INQ of vitamin $B_1$, vitamin $B_2$, vitamin C, calcium and phosphorous showed significantly negative correlations with food intakes, energy intakes and percentages of energy from night eating after the values were adjusted for age. These results suggest that among male university students, night snack intakes above 25% of energy have lower micronutrient qualities of vitamin $B_1$, vitamin $B_2$, vitamin C and calcium.

• Journal of Yeungnam Medical Science
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• v.10 no.1
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• pp.91-102
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• 1993

This study was carried out to assess medical care expenditure of residents in urban poor area. The study population included 377 family members of 85 households in the poor area of Daemyung 8-Dong, Nam-Gu, Taegu and 442 family members of 96 households in a control area. The data was collected through self-administered questionnaires completed by housewives. The survey was conducted from March 1 to May 31, 1992. The mean age was 31.1 years in the poor area and 37.1 years in the control area. The average number of households per house was 4.5 in the poor area and 4.5 in the control area. The frequency of medical care utilization per household in a one month period was 4.6 in the poor area and 4.3 in the control area. The average number of days of utilization was 12.9 in the poor area and 12.5 in the control area. The average monthly income of a househlod in the poor area was 848,600 Won compared to the control area's 1,752,300 Won. The average monthly consumption expenditure of a household in the poor area was 568,800 Won and that in the control area 1,238,400 Won. The average medical care monthly expenditure per household was 34,500 Won in the poor area and 58,400 Won in the control area. The proportion of the medical care expenditure to monthly income and to monthly consumption expenditure was 4.1% and 6.1% respectively in the poor area, and 3.3% and 4.7%, respectively in the control area. The premium of medical insurance was 1.5% in both areas. The proportion of cost for drug was 57.4%, for medical appliance was 1.2%, and for medical treatment was 41.1% in the poor area and in the control area 52.4%, 1.9%, 45.7%, respectively. The highest proportion of medical care expenditures in the poor area was herb clinic utilization (36.9%), while hospital and clinic(37.8%) was the highest proportion in the control area. Mean medical care expenditure per visit was 7,400 Won in the poor area and 12,600 Won in the control area. Mean medical care expinditure per day was 2.800 Won in the poor area and 6,300 Won in the control area.

• The Korean Journal of Financial Management
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• v.18 no.1
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• pp.23-41
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• 2001

본 연구에서는 여러 계량 모형을 이용하여 계산한 헤지 비율의 성과를 비교하였다. 특히 헤지 비율을 추정하기 위하여 분수 공적분 오차 수정 모형을 이용하였다. KOSPI200 현물과 선물 지수를 이용하여 검증한 결과 현물, 선물 지수는 1차 적분된 시계열이며 베이시스는 분수 적분된 시계열이었다. 따라서 현물과 선물 지수는 분수 공적분된 시계열이었다. 최소 분산 헤지 비율을 최적 헤지 비율로 하여 성과를 측정한 결과 다음과 같은 결과를 얻었다. 헤지 성과는 GARCH 항이 있는 모형이 없는 모형에 비해 크게 나타나며 각 모형에서 고려하고 있는 정보 집합의 크기가 큰 순서인 FIEC, EC, VAR, OLS 순으로 헤지 성과는 크게 나타나고 있다. 그러나 OLS 방법에 의한 헤지에 의해서도 수익률 변동의 많은 부분이 사라져, 다른 모형들은 OLS 모형과 비교하여 추가적인 분산 감소 효과는 크지 않았다.

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.10
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• pp.168-174
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• 2015

In this paper, we analyze the performance of cooperative communication techniques on an underwater channel. By analyzing the BER performance of cooperative transmission protocol and combining types ERC, FRC, SNRC and ESNRC on underwater channel, through the result, we can choose an a proper cooperative technique for an underwater channel. The analysis of BER performance is achieved by a computer simulation.

• The Korean Journal of Financial Management
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• v.16 no.2
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• pp.179-213
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• 1999

본 연구에서는 국내 주식시장에서 주식수익률의 횡단면 차이에 유의적인 설명력을 가지는 것으로 나타난 기본적 변수가 시장지수 베타에서는 측정되지 않은 또 다른 가격화된 위험에 대해 유용한 대용변수인지를 규명하였다. 기본적 변수들 중에서 기업규모와 장부/시장가치 비율은 주식수익률의 횡단면 차이를 설명함에 있어 독립적인 효과를 갖는 가장 유의적인 변수였다. 주식수익률의 횡단면 차이에 매우 유의적인 설명력을 가지는 깃으로 나타난 거시경제요인의 요인민감도는 기업규모, 장부/시장가치 비율을 포함시 더 이상 유의적인 설명력을 가지지 못하였다. 소규모, 높은 장부/시장가치 기업은 매우 지속적인 수익성 악화를 겪고 있는 곤경기업이며, 역시 배당감소위험, 레버리지위험 및 미래 현금흐름의 불확실성으로 측정된 기업특성적 위험이 보다 큰 곤경기업이었다. 따라서 이러한 실증결과는 소규모, 높은 장부/시장가치 주식이 대규모, 낮은 장부/시장가치 주식에 비해 높은 수익률을 보이는 원인이 보다 높은 위험에 따른 보상의 결과이며, 규모변수와 장부/시장 가치 비율은 이들 위험에 대한 유용한 대용치라는 '위험에 기초한 가설'을 지지하는 증거로 주장될 수 있다. 기업규모와 장부/시장가치 비율이 시장베타로는 측정되지 않는 주식가격결정에 있어 가격화 된 또 다른 위험을 대리한다면 수익률에 나타난 SIZE, B/M효과는 합리적 가격결정하 APT나 ICAPM과 같은 확장된 CAPM과 모순되지 않는 하나의 증거로 볼 수 있으며, 비록 이들 변수들이 관찰 불가능한 진정한 시장베타에 대한 보다 나은 대용치라고 할지라도 이들 두 변수와 관련된 요인을 포함한 다요인 가격결정모델이 시장지수만을 포함한 단일요인모델에 비해 보다 유용한 모형임을 기대할 수 있다.

• Journal of Educational Research in Mathematics
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• v.25 no.3
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• pp.431-448
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• 2015

This study is conducted to understand the real shape of confusion surrounding mathematical terminologies, 'ratio' and 'rate' in both the US and Korea and to get some implications for Korean education. For this, various materials including textbooks and materials for kids and teachers, dictionaries, educational internet web sites, the past Korean elementary mathematics curriculums and etc are reviewed with respect to the terminologies related to 'ratio' and 'rate'. As a result, the findings are as follows. Firstly, the US and Korea have different views with ratio and rate. Secondly, Korean terminologies related to ratio and rate are not enough to treat the essentials of the concept of ratio and rate.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.32 no.3
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• pp.357-368
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• 1987

The productivity of cropping systems with corn and soybean were tested in field layouts such as monocultures of each, I-row alternation(l：1), 1-row corn with 2-rows soybean(l：2), and 1-row corn with 3 rows soybean(l : 3). Increasing soybean rows in alternative row croppings modified corn plant short and thick stalk. Decreasing soybean rows induced lodging of soybean plants because of lengthy stem. Although LAI in alternative row croppings increased by 2-8% over monocultures, light transmition into canopy was improved in alternative rows with rearrangement of leaf area and top dry wt.. Top/root ratio of corn plants in alternative rows was decreased as increasing soybean rows. The amount of total nitrogen uptake was increased by 4-22% in alternative row croppings over monocultures. Grain yield of corn plants was increased and that of soybean was decreased as rows of soybean increased in alternative row croppings. Land equivalent ratios were ranged from 0.96 to 1.01, but grain yields, amount of total nitrogen, and dry matter yields were increased by 17-20, 10-25, and 17-20%, respectively, in alternative rows. The 1 : 1 alternative row of corn and soybean was concluded the best cropping system for production of grain and dry matter.