• 한국유기농업학회지
• /
• 제31권4호
• /
• pp.461-468
• /
• 2023

Supplying an appropriate amount of feed is an economical and environmentally friendly by increasing the nutrient digestibility of livestock and reducing nutrients released from overfeeding. Therefore, this study was conducted to determine the nutrient digestibility according to dietary feeding levels of Hanwoo steers. Three treatments in feeding trial were used feeding amount based on the maintenance energy level of the Korean feeding standard for Hanwoo (2022): 100% (control, CON), 140% (treatment 1, TRT1), and 190% (treatment 2, TRT2). The experiment was designed in replicate 3×3 balanced Latin square designs using six Hanwoo steers. In this study, energy value was predicted according to treatment groups. In addition, nutrient digestibility and energy value were measured through a feeding trial to Hanwoo steers. All energy values, including total digestible nutrients and digestible energy, were predicted to decrease linearly with increasing feeding levels. TRT2 showed lower digestibility than CON for dry matter, crude protein, non-fiber carbohydrates, and total digestible nutrients in the feeding trial (p<0.05). However, there was no significant difference between CON and TRT1. Total digestible nutrients (TDN) and digestibility of feed are set based on the maintenance energy. However nutrient digestibility and TDN decreased when feeding level increased by more than 190% compared to maintenance energy in this study. Therefore, it is necessary to correct the TDN by considering the feeding level when mixing the feed.

• 한국철도학회:학술대회논문집
• /
• 한국철도학회 2011년도 춘계학술대회 논문집
• /
• pp.1327-1335
• /
• 2011

Recently, also in railway vehicles, related products are being designed and manufactured through RAMS activities in order to secure their reliability, availability, maintainability & safety. Subway operators are conducting R&D on various preventive maintenance methods and applying them to the field so as to establish a reliability centered maintenance(RCM) system. In this connection, manufacturers shall carry out R&D based on reliability from the first design stage of development to provide high quality products to subway operators. And operators shall have the products operated properly to their particular operating environment and managed based on the standard maintenance manual. Not only that, but the related field data shall be fed back into the manufacturers to upgrade upcoming products by organic cooperation between manufacturer and operators. However, the mutually beneficial cooperative relationship is not still developed in the domestic railway industry. In terms of methodology for life prediction, this study was intended to analyze field data on relays used for rolling stocks considering operational characteristics in the position of subway operators and predict parts reliability using reliability prediction program from the standpoint of manufacturers as well.

• Tribology and Lubricants
• /
• 제26권1호
• /
• pp.73-77
• /
• 2010

One of the important trends for condition monitoring in the 21st century is the development of smart sensors that will permit the cost-effective continuous monitoring of key machine equipments. In this study, an integrated in-line oil monitoring sensor assigned for continuous in situ monitoring multiple parameters of oil performance is presented. The sensor estimates oil deterioration based on the information about chemical degradation, total contamination, water content of oil and oil temperature. The oil oxidation is estimated by "chromatic ratio", total contamination is measured by the changes in optical density of oil in three optical wave-bands ('Red', 'Green' and 'Blue') and water content is evaluated as relative saturation of oil by water. In order to evaluate the sensor's effectiveness, the sensor was applied to several used oil samples in steel making industry and the results were compared with those measured by standard test methods.

• Architectural research
• /
• 제16권1호
• /
• pp.17-25
• /
• 2014

This research is to restructure the public assessment of housing management in a standardized fashion, and a self-administered questionnaire survey was employed for data collection and analysis. In doing so, all the assessment tools nationwide were identified and assembled to extract the items included in the survey form. The survey form was mailed out to local officers in charge of housing management and professional housing managers in the nation, and the responses were statistically analyzed in order to structure the standard assessment tool of housing management. This research classified 3 main areas (General Maintenance, Operation and Community Living) in evaluating the housing management performance, and identified 35 essential items and 52 optional items. The 35 essential items were drawn from the 16 categories of the 3 areas (11 items of 5 categories for General Maintenance, 7 items of 4 categories for Operation, and 17 items of 7 categories for Community Living), and the rest 52 optional items were from the 16 categories of the 3 areas (24 items of 7 categories for General Maintenance, 26 items of 7 categories for Operation, and 2 items of 2 categories for Community Living). While all the items in the research are quantifiable, it's suggested that qualitative measurements be complementarily utilized in the assessment not only to explore the best practices of housing management but also to refine and modify the standardized tool in response to various environmental changes. As the public assessment of housing management is context-sensitive and critically related to local housing profile, the continuous implementation of the assessment will facilitate shifting the housing paradigm from production and consumption to management and reproduction.

• 대한물리의학회지
• /
• 제15권4호
• /
• pp.55-65
• /
• 2020

PURPOSE: This study examined the effects of breathing exercises via joint mobilization on the lung function and spinal alignment of 30 straight-necked women in their 20 s and 30 s. METHODS: The participants were divided into two groups: an experimental group who performed breathing exercises via joint mobilization, and a control group who performed general stretching exercises. The differences between the two groups were measured and compared at three points in time: during the pre-examination, after four weeks of intervention, and after a four-week maintenance period. The changes in each group were measured before and after the intervention and after a one-month maintenance period and compared. For data analysis, the SPSS 22 was used to obtain the mean and standard deviation with a significance level of α = .05. RESULTS: Eight weeks of breathing exercises via joint mobilization and general stretching exercises positively impacted the lung function and spinal alignment in straight-necked patients. In particular, the experimental group showed more significant differences in spinal alignment after four weeks period of intervention and four weeks of maintenance. CONCLUSION: Breathing exercises via joint mobilization can be considered an effective intervention that can improve the respiratory volume and spinal alignment for patients with straight necks.

• 한국건설관리학회논문집
• /
• 제8권5호
• /
• pp.132-141
• /
• 2007

BTL 사업 대상 중 교육시설물은 교육인적자원부에 따르면 2007년까지 3개년에 걸쳐 13조원 이상 규모의 BTL 민간투자 사업을 발주하기로 하는 등 교육시설물의 건설은 국내 공공시설물 건설 사업에서 큰 비중을 점하고 있다. 본 연구에서는 교육시설물 BTL 사업의 비용 항목 중 운영관리비에 해당되는 위생관리비 산정 방법을 제시하였다. 또한 이를 바탕으로 유지관리 시스템의 주요 모듈을 개발하고, 개발된 모델의 타당성을 입증하기 위해 대안별 비용의 비교 분석을 실시하였다.

• 해양환경안전학회지
• /
• 제26권1호
• /
• pp.15-21
• /
• 2020

본 연구는 ISO19030 - 선체 및 프로펠러 성능 모니터링 방법을 실선 178 k 벌크선박에 적용한 결과에 관한 것이다. 최근 온실가스 저감 규정 대응과 해운 경쟁력 확보를 위해 에너지 저감 솔루션을 선박에 적용하려는 시도가 증가하고 있다. 하지만 정량적으로 선박 성능을 분석하기 쉽지 않아 에너지 저감 솔루션의 평가가 쉽지 않았다. 이러한 해운 산업의 요구에 따라 2016년 ISO19030이 표준화되어 선박 성능 분석을 정량화할 수 있는 기반이 마련되었다. 하지만 ISO19030에서 제안하는 환경 보정법은 각 날씨 영향을 고려한 보정이 아닌 정수(Calm Sea) 상태에서 운항한 데이터만 분석하는 방식이다. 이러한 분석 방식은 선박의 운항 구간에 따라 데이터가 필터링 되는 편차가 심하고 정확한 환경 보정을 하지 않아 6개월 이하의 분석은 신뢰하기 어렵다. 본 연구에서는 ISO19030을 실제 3척 선박 3년 이상 장기간 운항 데이터에 적용하였다. 적용 결과를 토대로 ISO19030 효용성과 한계점을 파악하고 ISO19030에서 제안하는 필터링 방식 대신 ISO15016의 파도 보정(STA-WAVE2)을 통해 성능 분석 방법을 개선하고자 한다.

• 한국가스학회지
• /
• 제22권6호
• /
• pp.44-51
• /
• 2018

LNG저장탱크가 노후화 됨에 따라 외벽 콘크리트에 균열, 철근부식 등 결함이 발생할 경우, 손상 종류 및 정도에 따라 구조물의 붕괴 등 대형사고 발생 위험이 존재하게 된다. LNG저장탱크는 2014년부터 정밀안전진단이 시작 되어 안전점검이 수행되고 있으며, 부재별 상태평가기준은 2016년 1월에 개정되어 적용하고 있다. 상태평가는 액화천연가스 저장탱크에 대한 외관 조사 및 재료시험 결과를 바탕으로 저장탱크에 대한 상태를 평가하는 것을 말하는 것으로 유지관리에 있어서 중요하다. 또한 각각의 LNG 저장탱크 대표상태를 나타내는 종합적 상태평가기준이 유지관리 시 중요하지만, LNG저장탱크 외조 콘크리트에 대한 관련 기준이 국내 외에 부재하여 상태평가 기준 개발 필요하다. 이 논문에서는 LNG 저장탱크 구조적 특성 검토, 부재별 상태평가 기준현황 분석, 부재별 가중치 부여를 통한 종합적 상태등급 산정 방안을 수립하였다. 부재별 가중치 산출은 AHP(Analytic Hierarchy process)기법을 이용하고 전문기관의 설문조사 등을 통해 종합적 상태평가 기준을 개발하였다.

• 한국수자원학회논문집
• /
• 제56권3호
• /
• pp.185-194
• /
• 2023

국내에는 22,300개 이상의 소하천이 전국에 분포하고 있으며, 이들은 위치한 지역, 지형 및 토지 이용 상태에 따라 다양한 유출 특성을 갖는다. 소하천의 재난관리를 위해서는 소하천 특성에 적합한 세부 설계기준을 수립하는 것이 중요하다. 현재 국내 소하천설계기준에서 제시하는 개별 산정식들은 국내 중·대규모 하천이나, 외국 하천의 설계기준을 준용하고 있어 국내 소하천에 적합한 산정식 개발이 필요하다. 그 중 계획하폭은 하천의 규모를 결정하는 기준 중 하나로 현재 계획홍수량과 유역면적 등에 기반하여 결정하고 있다. 본 연구에서는 국내 소하천의 특성정보를 바탕으로 적정 계획하폭을 산정하기 위해, 국내 12개 시·도 4,073개 소하천의 다양한 특성정보와 계획하폭 정보를 수집하고 이들을 이용하여 회귀분석을 수행하였다. 이를 바탕으로 계획홍수량에 대한 1변수 계획하폭 산정식과 소하천의 계획홍수량, 유역면적, 하천연장, 하상경사에 따른 다변수 계획하폭 산정식을 도출하였다. 이렇게 산정된 소하천 계획하폭 산정식들은 소하천 설계기준 개선이나 소하천정비 종합계획 수립 등 소하천 재난관리에 활용될 수 있을 것으로 기대된다.

• 한국측량학회:학술대회논문집
• /
• 한국측량학회 2004년도 춘계학술발표회논문집
• /
• pp.329-335
• /
• 2004

Until now, The our concept about a national geospatial data infrastructure have been concentrated on a field of producer. This concept is the trend which the focus have been inverted currently with the use to process data in an user viewpoint and to the compatibility of the database. But the standard of our national framework data is defective yet. Also, The law and policy are not clear and the concept recognition of users lacks. This paper is showed improvement plan of development and maintenance of the national framework data, and researched the relationship between the national framework data.