• 한국철도학회논문집
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• 제20권1호
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• pp.11-19
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• 2017

도시철도 차량의 운행은 터널 공기를 오염시키는 주된 원인이므로, 마모입자를 제거하는데 집진장치가 유용한 수단이 될 수 있다. 차량의 하부에 장착될 수 있는 집진장치의 설계조건을 파악하기 위하여 3차원 초음파 풍속계와 입자측정기를 사용하여 차량 하부의 풍속과 입자농도를 조사하였다. 2015년 2월 10일 수도권 지하철 5호선에서 운행되는 차량을 대상으로 측정하였다. 측정자료는 역 사이 노선의 형상(직선, 곡선)과 차량 속도패턴(가속, 정속 및 감속)을 구분하여 분석하였다. 차량속도도 함께 분석하였다. 직선 및 곡선 구간 모두 차량 하부의 평균 풍속은 차량속도의 약 30%이었고, 미세먼지($PM_{10}$) 농도는 약 $200{\mu}g/m^3$이었다. 감속구간에서 평균 $PM_{10}$ 농도는 가속구간에 비해 더 높았다.

• 청정기술
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• 제4권1호
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• pp.60-67
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• 1998

환경문제에 대한 사회적 관심이 높아지면서 작업환경의 개선에 대한 필요성이 증가하고 있으며, 특히 부유분진으로부터 작업자들을 보호하는 것은 중요하다. 현재 산업체에서 가장 많이 사용되고 있는 분진 제거 방법은 면체 마스크이다. 면체 마스크는 1회용이어서 비용이 많이 들고 그 편리성에 비해 인체에 유해한 입자에 대해서는 낮은 여과 효율을 가지고 있다. 본 연구에서는 기존 면체 마스크를 대체할 수 있는 새로운 형태의 흡 배기판을 가진 반면형 송기 마스크를 개발하였다. 마스크는 HEPA 휠터가 장착된 송풍기를 통과한 깨끗한 공기를 안면에 공급하게된다. 개발된 송기 마스크는 성능 테스트와 현장 테스트를 실시하였고, 매우 양호한 결과를 얻었다.

• 한국응용과학기술학회지
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• 제40권5호
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• pp.945-954
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• 2023

In this study, Sparassis crispa(cauliflower mushroom), which is rich in beta-glucan, was pulverized using ultrafine grinding technology for its potential utilization as a diverse food ingredient. The physical and antioxidant properties of cauliflower mushroom powder were evaluated at various grinding times. The results showed that as the grinding time of cauliflower mushroom increased, the average particle size significantly decreased (p<0.05). Additionally, the water-holding capacity, swelling capacity, and water solubility index of cauliflower mushroom increased significantly(p<0.05). Based on the analysis mentioned above, cauliflower mushroom prepared as a superfine powder for 5 minutes exhibited superior physical and chemical properties as well as antioxidant characteristics and is expected to be widely used in various foods.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회 1995년도 추계학술대회발표논문집; 서울대학교, 서울; 30 Sep. 1995
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• pp.156-169
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• 1995

The purpose of this paper is to investigate the role of government in innovation. That is, how much should government invest in R&D activity for social welfare enhancement. An optimal control problem is proposed to answer the above question. Because of difficulties in solving the problem, simulation utilized to find an approximate solution. All results obtained from the simulation are very similar. The investment in R&D activity increases and reaches its maximum and then decreases continuously. If the importance of technology grows the investment in R&D activity should be expanded.

• Journal of Animal Science and Technology
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• 제65권1호
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• pp.244-257
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• 2023

The study aimed to investigate the effect of low-frequency oscillations on the cow udder, milk parameters, and animal welfare during the automated milking process. The study's objective was to investigate the impact of low-frequency oscillations on the udder and teats' blood circulation by creating a mathematical model of mammary glands, using milkers and vibrators to analyze the theoretical dynamics of oscillations. The mechanical vibration device developed and tested in the study was mounted on a DeLaval automatic milking machine, which excited the udder with low-frequency oscillations, allowing the analysis of input parameters (temperature, oscillation amplitude) and using feedback data, changing the device parameters such as vibration frequency and duration. The experimental study was performed using an artificial cow's udder model with and without milk and a DeLaval milking machine, exciting the model with low-frequency harmonic oscillations (frequency range 15-60 Hz, vibration amplitude 2-5 mm). The investigation in vitro applying low-frequency of the vibration system's first-order frequencies in lateral (X) direction showed the low-frequency values of 23.5-26.5 Hz (effective frequency of the simulation analysis was 25.0 Hz). The tested values of the first-order frequency of the vibration system in the vertical (Y) direction were 37.5-41.5 Hz (effective frequency of the simulation analysis was 41.0 Hz), with higher amplitude and lower vibration damping. During in vivo experiments, while milking, the vibrator was inducing mechanical milking-similar vibrations in the udder. The vibrations were spreading to the entire udder and caused physiotherapeutic effects such as activated physiological processes and increased udder base temperature by 0.57℃ (p < 0.001), thus increasing blood flow in the udder. Used low-frequency vibrations did not significantly affect milk yield, milk composition, milk quality indicators, and animal welfare. The investigation results showed that applying low-frequency vibration on a cow udder during automatic milking is a non-invasive, efficient method to stimulate blood circulation in the udder and improve teat and udder health without changing milk quality and production. Further studies will be carried out in the following research phase on clinical and subclinical mastitis cows.

• 가정과삶의질연구
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• 제27권4호
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• pp.19-30
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• 2009

The essence of family health is to make the family stronger, which can be found in the philosophy of coaching that focuses on the individual's own change and development. In this context, this study aims to develop a coaching educational program at the Healthy Family Support Center. The educational program, 'The Happiness Balloon in My Mind' consists of 4 sessions, which are 'Perceiving the Balloon', 'Making the Balloon', 'Blowing up the Balloon', and 'Flying the Balloon'. Through the questionnaires that included open and closed questions, the effectiveness of the program was evaluated. The educators replied that their expectation to the program was met and they were highly satisfied with the program. They reported that the program brought the a change in life, elly, in their own consciousness. Even though the program would need to adjust its level of difficulty and scheduling, the results suggest that coaching educational program showsits own plausibility to the Healthy Family Support Center.

• 한국컴퓨터정보학회논문지
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• 제20권5호
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• pp.133-140
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• 2015

이 연구는 청소년의 학업스트레스가 자살충동에 이르는 인과경로에 있어서 인과관계가 성(gender)에 따라 차이가 있는지를 검증해 봄으로써 시사점을 도출해 보는데 연구목적을 두었다. 이를 위해 고등학교 학생들을 대상으로 표본을 추출하여 설문조사를 실시하였다. 이 연구의 분석결과, 청소년의 학업스트레스는 우울감을 통하여 자살충동에 직 간접적으로 영향을 미치는 것으로 나타났으며, 학업스트레스와 우울감 사이의 인과관계와 우울감과 자살충동 사이의 인과관계에서 성별 차이가 있는 것으로 나타났다. 이 연구에서는 이러한 분석결과를 토대로 시사점을 도출하였다.

• 한국직업건강간호학회지
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• 제16권2호
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• pp.222-231
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• 2007

Purpose: This study aims to suggest political alternatives for nursing care costs for PCAs to provide qualitative medical benefit for patients with occupational disease by investigating present situation and problems of the nursing care cost system of Korea's Industrial Accident Compensation Insurance. Methods: Data was collected from 6 workers' accident medical corporation and 275 nurses affiliated with Korea labor welfare corporation using self reported questionnaire. Result: Research results were as follows; Character of nursing care cost of the Korea's Industrial accident Compensation Insurance changed as if it aims to support for living expenses for the family; As possible problems which could be caused under current system, administrative problems, decrease of service quality were made as objects of criticism. Some patients did not make every effort in rehabilitation to be beneficiaries continuously. Some patients were supplied with whole one PCA or all-night PCA even though they did not need as much caring as such. Conclusion: The research suggested that PCAs payment system improvement is necessary, and the presented nurses' opinion for the improvement method could be applied for policy making.

• 한국축산시설환경학회지
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• 제16권2호
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• pp.129-134
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• 2010

본 실태조사는 분만돈방과 분만틀 사용실태를 조사함으로써 분만돈의 동물복지 수준을 향상시킬 수 있는 대체 사육시설을 개발하는데 필요한 기초자료를 확보하기 위해 실시되었다. 분만돈방은 크게 형태별로 수직형 분만돈방과 사선형 분만돈방 두 가지로 구분되었으며, 분만틀은 압사방지 바(Bar)의 형태를 기준으로 수평형(Horizontal bar) 분만틀, 수직형(Vertical bar) 분만틀로 구분되었다. 기타 시설물에 대한 조사결과, 조사농가의 전체가 니플형 급수시설을 사용하고 있었으며, 약 80%가 습식급이기를 사용하고 있었고, 조사 농가의 약 40%가 전체틈바닥, 약 60%가 부분 틈바닥이었으며, 분만돈 두당 최소 $3.9\;m^2$ 이상의 면적을 제공하고 있었다. 국내의 다양한 사육시설과 환경으로 인하여 일괄적인 구조개선이나 새로운 사육시설의 적용은 쉽지 않을 것으로 판단되지만 이러한 국내 양돈농가의 실태조사 자료들을 동물복지 수준을 향상시킬 수 있는 대체 사육시설을 개발하는데 좋은 기초자료가 될 것이라 생각한다.

• 한국축산식품학회지
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• 제44권2호
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• pp.326-355
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• 2024

Expectations for the industrialization of cultured meat are growing due to the increasing support from various sectors, such as the food industry, animal welfare organizations, and consumers, particularly vegetarians, but the progress of industrialization is slower than initially reported. This review analyzes the main issues concerning the industrialization of cultured meat, examines research and media reports on the development of cultured meat to date, and presents the current technology, industrialization level, and prospects for cultured meat. Currently, over 30 countries have companies industrializing cultured meat, and around 200 companies that are developing or industrializing cultured meat have been surveyed globally. By country, the United States has over 50 companies, accounting for more than 20% of the total. Acquiring animal cells, developing cell lines, improving cell proliferation, improving the efficiency of cell differentiation and muscle production, or developing cell culture media, including serum-free media, are the major research themes related to the development of cultured meat. In contrast, the development of devices, such as bioreactors, which are crucial in enabling large-scale production, is relatively understudied, and few of the many companies invested in the development of cultured meat have presented products for sale other than prototypes. In addition, because most information on key technologies is not publicly available, it is not possible to determine the level of technology in the companies, and it is surmised that the technology of cultured meat-related startups is not high. Therefore, further research and development are needed to promote the full-scale industrialization of cultured meat.