• Title/Summary/Keyword: international physical distribution

검색결과 162건 처리시간 0.023초

강우입자분포를 고려한 시강우의 강우에너지 산정 연구 (Estimation of the Kinetic Energy of Raindrops for Hourly Rainfall Considering the Rainfall Particle Distribution)

  • 김성원;정안철;이기하;정관수
    • 한국지반환경공학회 논문집
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    • 제19권12호
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    • pp.15-23
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    • 2018
  • 우리나라에서 발생하는 대부분의 토양침식은 물에 의한 토양침식이며 강우와 밀접한 관계를 가진다. 강우로부터 발생하는 토양침식은 토지자원의 손실을 발생시키고 이후 하천에 유입되고 퇴적되어 하천수자원의 관리 및 이용에 많은 어려움을 주고 있다. 최근 기후변화의 영향으로 우리나라에서는 30mm/hr 이상의 집중호우의 발생횟수가 증가하고 있어 단기간에 토양침식이 발생할 가능성이 높아지고 있다. 본 연구에서는 강우의 물리적인 특성을 고려하기 위하여 누적분포함수를 이용하여 강우강도별 강우입자의 분포를 추정하고 단일 호우사상이 가지는 강우에너지를 계산하는 방법을 제안하고자 하였다. 강우에너지 산정공식을 개발하기 위하여 강우강도 0.254~152.4mm/hr에서 측정된 강우입자 자료를 이용하였다. 누적분포함수를 적용하여 산정된 강우에너지는 강우강도의 관계에서 멱함수형태로 증가하는 경향으로 나타났으며, 이 관계로 얻어진 식을 바탕으로 1~80mm/hr 강우강도의 강우 운동에너지를 산정한 결과 $0.03{\sim}48.26Jm^{-2}mm^{-1}$로 나타났다. 강우강도와 강우에너지의 관계를 바탕으로 강우에너지 식을 멱함수로 제시하였다. 본 연구에서 제안된 공식은 한시적으로 설치하는 침사지와 같은 시설물의 규모를 결정하는 계획의 토양침식량을 예측에 활용될 수 있을 것으로 판단된다.

스포츠 콘텐츠 유통의 새로운 패러다임: 스포츠의 뉴미디어화 (A New Paradigm in the Distribution of Sport Contents: Sports as a New Media)

  • 박성희;한승진;서원재
    • 유통과학연구
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    • 제15권10호
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    • pp.93-103
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    • 2017
  • Purpose - Sports and the media have been developed together through a close relationship. During the past decade, the media landscape and the coverage of sports events have been changed. Sports fans can use the sports content at the time they want, on the platform they prefer. Furthermore, thanks to the advanced information technology, sports fans are likely to be more engaged in sport in communication technology-friendly stadium. However, the literature on the relationship between sports and the media has heavily focused on the differences of media types, clear distinction between media suppliers and consumers, and the limited media extension. Given the limitation of prior research, therefore, it has not fully reflected the change in society and culture, the importance of media recipients or consumers, and the mediating characteristic of the media. In order to generate further insights for sport media related industry and its society, it is necessary to comprehend the contemporary phenomena of real world situation in new media and sport and to discuss how new media influence sport and how their relationship is changing in managerial context. The purpose of this study is to identify new media cases as distribution channels in sports context and is to develop insights by discussing its role and meaning of new media in sport society. Research design, data, and methodology - The study employed the theory-centered review and case analysis. In order to explain phenomena of the role of new media in contemporary sport and to generate related insights in sport context, the study reviewed the new media cases applied in sport industry and interpreted their meaning by employing medium theory, remediation theory, and new media theory. Results - The study discussed the limitation of prior sport media research and identified the characteristics of sport as new media such as remediating, extending sensory organs, reiterating physical space and electronic space. Conclusions - The study derived the characteristics of sport as new media, in a sport setting, and through sports settings. Findings would assist to comprehend the role of new media in spectating sport and provide insights for sport media study.

노란잔산잠자리(Macromia daimojiOkumura, 1949)의 서식지 특성 및 기후변화에 따른 잠재적 분포 예측 (Habitat characteristics and prediction of potential distribution according to climate change for Macromia daimoji Okumura, 1949 (Odonata: Macromiidae))

  • 권순직;권혁영;황인철;이창수;김태근;박재흥;전영철
    • 한국습지학회지
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    • 제26권1호
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    • pp.21-31
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    • 2024
  • 우리나라는 노란잔산잠자리(M. daimoji Okumura, 1949)를 멸종위기 야생생물로 지정하여 보호하고 있고, 국가적색목록 평가에서 위기(EN)로 등재하였다. 이들은 주로 동북아지역에 서식하는데, 우리나라에는 위도상 사천시(35.1°)부터 연천군(38.0°)까지, 경도상 연천군(126.8°)부터 양산시(128.9°)까지 관찰되었다. 서식지는 저지대의 평지하천에 하상재료가 모래로 이루어져 있고, 유속이 완만한 하천의 가장자리와 하중도의 가장자리, 하천 구역에 일시적으로 형성된 웅덩이를 선호한다. 노란잔산잠자리 출현 지점에서의 저서성 대형무척추동물 군집구조는 낙동강 본류의 경우 서식지에 따라 군집 조성의 차이가 적었고, 지류의 경우 주변 환경과 하천의 규모에 따라 낙동강 본류보다 군집 조성의 차이가 컸다. 현재 분포지역을 토대로 MaxEnt 모델을 이용하여 잠재적 분포를 예측한 결과, 낙동강 본류와 지류에 서식할 가능성이 높았다. 환경변수 중 기여도는 BIO03(36.2%), BIO10(15.8%), BIO14(13.8%), BIO12(12.5%), BIO08(6.1%) 등의 순으로, 모형에 대한 중요도는 BIO10(43.7%), BIO14(14.6%), BIO17(13.78%), BIO13(9.8%), BIO02(6.7%), BIO18(5.2%) 등의 순으로 높았다. 노란잔산잠자리의 공통사회경제경로를 통한 미래 분포 예측에 있어서 재생에너지 기술 발달로 화석연료 사용을 최소화한 SSP1은 서식가능지역이 넓은 범위에서 확대되었으며 산업기술의 빠른 발전에 중심을 두어 화석연료 사용이 높고 도시 위주의 무분별한 개발이 확대될 것을 가정한 SSP5는 대체로 증가하는 것으로 예측되었다. 이들의 서식지는 하천공사, 골재채취 등과 같은 물리적 환경변화와 강우 강도의 증가에 의한 홍수 등 급변하는 기후변화에 영향을 받을 것으로 판단된다. 따라서 노란잔산잠자리 보호를 위해서는 생태계 환경변화관찰을 위한 장기적인 모니터링 수행과 개체군 유지를 위한 보전방안 수립이 요구된다.

영산강수계의 죽산보에 설치된 어도에서 어류의 이동성 평가 (Fish Passage Assessments in the Fishway of Juksan Weir Constructed in the Downstream Area of Youngsan-River Watershed)

  • 박찬서;안광국
    • 한국환경과학회지
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    • 제23권8호
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    • pp.1513-1522
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    • 2014
  • Fish passage asssessments were conducted in the fishway at Juksan Weir, which was constructed as a four-major rivers project in the downstream area of Youngsan-River Watershed. For the research, fish-movements/migrations were analyzed for seven times from April ~ October, 2013 using an approach of fish trap-setting. Fish fauna and compositions were analyzed in the fishway, and seasonal- and diel-movement patterns were analyzed in relation to current velocity in the fishway. Also, abundances of exotic fishes such as bluegill sunfish (Lepomis macrochirus), large-mouth bass (Micropterus salmoides), and white curcian carp (Carassius cuvieri) were monitored in the fishway. Current velocity(n = 18) in the fishway showed large variations ($0.82{\pm}0.63m/s$) depending on the location of the fish trap-setting and this physical factor influenced the fish movements. Fish movements, based on the CPUE of individuals, in the fishway was greater in slower velocity (mean: 0.36 m/s, range: 0.10~1.54 m/s) than faster velocity (mean: 1.51 m/s, range: 0.90~1.90 m/s). Seasonal analysis of fish movements showed that most frequent uses (8 speices and 591 individuals, 66.2% of the total) of the fishway occurred in spring period(i.e., June). Diel movement analysis, in the mean time, showed highest in the time period of 00:00 ~ 3:00 am (7 species and 281 individuals, 20.9% of the total). The efficient managements in the fishway at Juksan Weir are required in relation to the hydrological regime.

k-최단 분리 경로 배정을 적용한 장애 복구형 선박 백본 네트워크의 성능 평가 (Performance Evaluation of a Survivable Ship Backbone Network Exploiting k-Shortest Disjoint Paths)

  • 탁성우
    • 한국정보통신학회논문지
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    • 제16권4호
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    • pp.701-712
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    • 2012
  • 장애 복구형 백본 네트워크에서 경로의 짧은 거리 및 빠른 전파 지연시간은 주 경로와 백업 경로의 설정시 활용될 수 있는 중요한 성능 인자이기에 이에 $k$-최단 분리 경로 개념은 이러한 백본 네트워크 환경에서 매우 중요하게 고려된다. 이에 본 논문에서는 선박 장비 간의 중복 메시지 전송 기능을 명세하는 IEC61162-410 표준이 적용된 장애 복구형 선박 백본 네트워크에서 $k$-최단 분리 경로 개념의 적합성을 비교 평가하였다. 성능 평가는 링크 용량, 주경로 및 백업 경로의 홉 및 거리, 트래픽 흐름의 균등 분포, 백업 경로의 장애 복구 시간, 그리고 물리 네트워크 토폴로지의 연결성 측면에서 수행되었다.

폐 수용성 절삭유의 화학처리효과 및 물성변화 (Effect of chemical treatment and variations of the physical properties of waste water-soluble cutting oil)

  • 신춘환;장정국
    • 한국환경과학회지
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    • 제13권4호
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    • pp.403-412
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    • 2004
  • Waste water-soluble cutting oil was treated with WI type #1 and WI type #2. The properties of the original water-soluble cutting oil were pH=l0.4, viscosity=1.4cP, CODcr=44,750 ppm, and TOC=10,569 ppm. However, the properties of the oil used for more than 3 months were changed to pH=7.82, viscosity=2.1cP, CODcr=151,000 ppm, and TOC=74,556 ppm. It might be attributed to the fact that molecular chains were cut due to thermal oxidation and impurities such as metal chips were incorporated in to the oil during the operation processes. To prevent the putrefaction of oil, the sterilization effect of ozone and UV on the microorganism in the oil was investigated. Ozone treatment showed that 99.99% of the microorganism was annihilated with 30 minutes contact time and 60 minutes were necessary for the same effect when UV was used. Ozone treatment could cut molecular chains of the oil due to strong sterilization power, which was evidenced by the increase of TOC from 25,132 ppm at instantaneous contact to 28,888 ppm at 30 minutes contact time. However, UV treatment didn't show severe changes in TOC values and thus, seemed to cause of severe cut of molecular chains. When the activated carbon was used to treat the waste water-soluble cutting oil, TOC decreased to 25,417 ppm with 0.lg carbon and to 15,946 ppm with 5.0g carbon. This results indicated that the waste oil of small molecular chains could be eliminated by adsorption. From the results, it could be concluded that these treatment techniques could be proposed to remove the waste oil of small molecular chains resulting in the degradation of the oil properties. In addition, these experimental results could be used for the correlation with future works such as investigation of the molecular distribution according to the sizes, lengths, and molecular weight of the chains.

Incorporation of CrusHed Sands and Tunisian Desert Sands in the Composition of Self Compacting Concretes Part I: Study of Formulation

  • Rmili, Abdelhamid;Ouezdou, Mongi Ben;Added, Mhamed;Ghorbel, Elhem
    • International Journal of Concrete Structures and Materials
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    • 제3권1호
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    • pp.3-9
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    • 2009
  • This paper examines the incorporation of the crushed sand (CS) and desert sand (DS) in the formation of self compacting concrete (SCC). These sands have been substituted for the rolled sand (RS), which is currently the only sand used in concretes and which is likely to run out in our country. DS, which comes from the Tunisian Sahara in the south, is characterized by a tight distribution of grains size. CS, a by-product of careers containing a significant amount of fines up to 15%, is characterized by a spread out granulometry having a maximum diameter of around 5mm. These two sands are considered as aggregates for the SCC. This first part of the study consists in analyzing the influence of the type of sand on the parameters of composition of the SCC. These sands consist of several combinations of 3 sands (DS, CS and RS). The method of formulation of the adopted SCC is based on the filling of the granular void by the paste. The CS substitution to the RS made it possible, for all the proportions, to decrease the granular voids, to increase the compactness of the mixture and to decrease the water and adding fillers proportioning. These results were also obtained for a moderate substitution of DS/CS (< 40%) and a weak ratio of DS/RS (20%). For higher proportions, the addition of DS to CS or RS did not improve the physical characteristics of the SCC granular mixture.

활성탄의 세공크기와 흡착질의 물리적 특성과의 연관성이 흡착에 미치는 영향 (Adsorption Affected by Relationship Between Pore Sizes of Activated Carbons and Physical Properties of Adsorbates)

  • 강정화;권준호;김상원;송승구
    • 한국환경과학회지
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    • 제16권3호
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    • pp.377-383
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    • 2007
  • In this study, the relationship between the pore size distribution and the adsorption amount of adsorbates is investigated in detail. Adsorption amounts of non-polar adsorbates were greater than those of polar adsorbates because of slight negative charge on surfaces of adsorbents. The adsorption of benzene on the surface of absorbents was largely influenced by the specific pore size of $2{\sim}4$ times of benzene diameter. But in case of toluene, the adsorption of toluene was affected by pore sizes of $2{\sim}4$ times as well as $4{\sim}6$ times of the diameter of toluene. Both acetone and MEK were examined by the same method. The adsorption of acetone was influenced by pore sizes of $2{\sim}4$ times of the diameter of acetone. But acetone does not look to be built up multi-layer on those pore sizes. Since acetone molecule is small and its mobility is so fast, it is assumed that the adsorption and desorption of acetone is simultaneously occurred at the same time even at room temperature. In case of MEK, MEK was effected by pore sizes of $2{\sim}4$ times of the diameter of MEK.

3D 가상 의상 기술을 활용한 캐쥬얼웨어 디자인 연구 - Z 세대를 중심으로 (A study on Design of Casual wear utilizing 3D Virtual Clothing Technology - focus on Generation Z)

  • 신혜경
    • 문화기술의 융합
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    • 제7권1호
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    • pp.75-81
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    • 2021
  • 첨단 정보통신 기술의 발달에 따라 디지털 문화에 익숙한 Z세대는 미래 패션을 재편할 수 있는 패션 산업의 주요 소비층으로 관심이 집중되고 있다. 본 연구에서는 디지털 기기에 능숙하고 인터넷을 통한 정보 습득 및 모바일 라이프스타일에 친숙한 Z세대를 위한 캐쥬얼웨어를 3D 가상 시뮬레이션에 의해 디자인하여 걸리쉬, 스포티브, 이지, 컨템포러리의 4가지 룩으로 디자인 전개하였다. 의상디자인에 3D 가상 착의 시뮬레이션의 활용은 팬데믹 환경에서 디지털 패션 디자인기획 및 생산 프로세스와의 융합을 통한 미래 패션 산업의 디지털화를 구축하고 온라인 플랫폼의 유통을 강화시킬 수 있다. 언택트 패션 제작 시스템을 도입하여 업무의 효율성 강화를 위한 지속적인 혁신을 시도하고 있는 기업 환경에서 3D 가상의상 기술의 활용은 3D 샘플 제작, 온라인 피팅, 수정과 보정 및 품평을 통해 업무 프로세스에서 소통이 확대되고 인적, 물적 자원의 경감에 따른 긍정적 효과를 통해 지속 가능한 패션의 가치를 확대시킬 수 있다.

How Retirees' Evaluation of Starting Food Service Business Affects Effectiveness of Their New Business and Quality of Life

  • Lim, Jeoung-sook;Ryu, Ki-hwan
    • International Journal of Advanced Culture Technology
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    • 제9권4호
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    • pp.18-28
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    • 2021
  • This study surveyed how retirees' evaluation of starting food service business affects the effectiveness their new business and quality of life, based on personal factors such as entrepreneurship and business-starting capability and environmental factors by using questionnaires. Bootstrapping was carried out in order to find out factors affecting rapidly changing new business environments and retirees' initial intent to start a business so as to verify basic hypothesis about relation between retirees' evaluation of starting food service business (social, economic, and psychological effects) and the effectiveness of their new business and quality of life and confirm whether the effectiveness of the new business acts as a medium between the evaluation of starting food service business and quality of life. In addition, PLS-MGA was performed in order to verify whether the correlations among test factors can be varied according to the kind of job the target retirees had. Having examined the basic thesis, it was found that social and economic factors had significant positive effect on the effectiveness of the new business, and social and psychological factors had significant positive effect on the quality of life. Having analyzed whether the effectiveness of new business acted as a media between evaluation of starting food service business and quality of life, there was no significant effect as a medium. Having studied whether the kind of job of the retirees controlled or affected the relations among evaluation of starting food service business, effectiveness of new business and quality of life, the results were as follows: in the office job retiree group, the greater economic factor led to increase of effectiveness of new business, while social and psychological factors influenced the quality of life; In the physical labor group, the higher social factor resulted in higher effectiveness of new business, which showed significant positive effect on the quality of life. Having researched about which element is considered to be most important in starting food service business, the most important element was found to be dish/menu, followed by staff management, accounting management, business management, and service education. Having analyzed relation between accomplishment and important consideration for starting food service business, "managers with entrepreneurship," "appropriate distribution of time to prepare for starting business," and "operation of practical field education programs" showed higher importance compared to the degree of satisfaction, so it is needed to more concentrate on the above matters. This study intends to raise retirees' awareness of starting business and help them live better life based on the analysis results, and further suggest detailed mechanism and specific operations of factors affecting retirees' decision making on starting business, such that they can use the information as basic materials to make better choices that can lead to successful business.