• 제목/요약/키워드: fast green

검색결과 255건 처리시간 0.017초

리기테다소나무와 백합나무(yellow poplar)의 열기건조스케줄 개발 (Development of Kiln-Dry Schedules for Pinus $rigida{\times}taeda$ and Liriodendron tulipifera)

  • 이관영;강호양;정성호;정두진
    • 한국가구학회지
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    • 제11권1호
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    • pp.69-74
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    • 2000
  • Pinus $rigida{\times}taeda$ and Liriodendron tulipifira have been planted in this country for about 20 years. They are known as a relatively 13st-grown and useful species. The physical properties such as green moisture contents, specific gravities and dimensional shrinkages were examined with natively grown timbers. The kiln-dry schedules were developed with 30m thick boards by using an oven-fast-drying method. In both species the green MC's of sapwoods were higher than those of heartwoods, but their discrepancies were small. The green specific gravities of Pinus $rigida{\times}taeda$ and Liriodendron tulipifera were 0.48 and 0.41~O.42, respectively. The developed kiln-dry schedules were proven to minimize drying defects for the hoards of 30mm thickness and various width.

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A calculation method for finite depth free-surface green function

  • Liu, Yingyi;Iwashita, Hidetsugu;Hu, Changhong
    • International Journal of Naval Architecture and Ocean Engineering
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    • 제7권2호
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    • pp.375-389
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    • 2015
  • An improved boundary element method is presented for numerical analysis of hydrodynamic behavior of marine structures. A new algorithm for numerical solution of the finite depth free-surface Green function in three dimensions is developed based on multiple series representations. The whole range of the key parameter R/h is divided into four regions, within which different representation is used to achieve fast convergence. The well-known epsilon algorithm is also adopted to accelerate the convergence. The critical convergence criteria for each representation are investigated and provided. The proposed method is validated by several well-documented benchmark problems.

마이크로스트립 구조에 관한 새로운 closed-form 그린함수 유도를 위한 견실한 방법과 빠른 모멘트법으로의 응용 (A robust method for derivation of the new closed-form Green관s functions for microstrip structures and its application to a fast MoM)

  • Kim, Eui-Joong
    • 한국전자파학회:학술대회논문집
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    • 한국전자파학회 2002년도 종합학술발표회 논문집 Vol.12 No.1
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    • pp.423-433
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    • 2002
  • A very fast method of moments(MoM) for the analysis of microstrip structure is considered based upon the use of rooftop basis and razor test functions in conjunction with a new closed-form Green's functions. The present method presents a robust approach to obtain the Green's functions which can be derived by use of only one set of approximation parameters independently of operating frequency range. Moreover, using the present MoM scheme, the MoM matrix elements can be analytically evaluated with few number of terms in comparison with the previous method. So, the computational efficiency can be improved significantly without loss of the precision. In order to check the validity of the present method, performance is demonstrated for the example of a coaxially-fed microstrip transmission line and the present results are compared with the previous results.

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퍼팅그린 관리 장비 유형에 따른 그린스피드 차이 비교 (Comparative Study on the Green Speed by different the Types of Putting green Maintenance Equipment)

  • 장유비;심경구
    • 아시안잔디학회지
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    • 제18권1호
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    • pp.37-46
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    • 2004
  • 본 연구는 골프코스관리자들이 빠른 그린관리를 위한 장비 사용 계획시 참고가 될 수 있는 기초자료를 제공하고자 그린모아 유형(보행식, 승용식)에 따른 그린스피드 차이, 보행식 그린모아에 장착된 회전날 유형(9날, 11날)에 따른 그린스피드 차이 그리고 롤러 유형(승용식 그린정리기, 경량롤러)에 따른 그린스피드 차이를 비교하였다. 그 결과의 요약은 다음과 같았다. 1. 그린모아 유형(보행식, 승용식)에 따른 그린스피드 차이는 깎기 후 바로 그리고 깎기 후 8시간 경과 뒤에도 보행식 그린모아를 사용한 3.8mm 깎기 처리구가 승용식 그린긴아를 사용한 3.8mm 깎기 처리구에 비해 그린스피드가 빠르게 나타났고 이는 95% 유의수준에서 통계적으로 유의한 결과였다. 따라서 보행식 그린모아가 승용식 그린모아에 비해 빠른 그린 관리에 적합한 장비 유형으로 판단되 었다. 2. 그린모아에 장착된 회전날 유형(9날, 11날)에 따른 그린스피드 차이는 11날 장착 보행식 그린모아를 사용한 3.2mrn 깎기 처리구가 9날 장착 보행식 그린모아를 사용한 3.2mm 깎기 처리구에 비해 그린스피드가 빠르게 나타났고 이는 95% 유의수준에서 통계적으로 유의한 결과였다. 따라서, 11날이 9날보다 빠른 그린관리에 적합한 회전날 유형으로 판단되었다. 3. 보행식 그린모아로 3.0mm로 깎기한 다음이어서 승용식 그린정리기로 1회 롤링한 처리구와 보행식 그린모아로 3.0mm로 깎기한 다음 이어서 경량롤러로 1회 롤링한 처리구간의 그린스피드 차이(다짐후 그린스피드 증가효과)는 95% 유의수준에서 통계적으로 유의하지 못했으나 8시간 경과 뒤에 측정한 두 처리구들의 그린스피드의 차이(다짐후 그린스피드 감소효과)는 95% 유의수준에서 통계적으로 유의한 결과를 나타냈다. 따라서, 경량롤러가 승용식 그린정리기 보다 빠른 그린관리에 적합한 롤러유형으로 판단되었다.

근미래 친환경 건축분야 엔지니어에게 필요한 역량에 대한 델파이 연구 (A Delphi Study on Competencies of Future Green Architectural Engineer)

  • 강소연;김태연;이정우
    • 공학교육연구
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    • 제21권3호
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    • pp.56-65
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    • 2018
  • With rapid advance of technologies including information and communication technologies, jobs are evolving faster than ever. Architectural engineering is no exception in this regard, and the green architectural engineering is emerging fast as a promising new field. In this study, a Delphi study of expert architectural engineers are conducted to find out (1) near future prospects of the field, (2) near future emerging jobs, (3) competencies needed for these jobs, and (4) educational content necessary to build these competencies with regards to the green architectural engineering. Initial Delphi survey consisting of open-ended questions in the above four areas were conducted and came out with 65 items after duplicate removal and semantic refinements. Further refinements via second and third wave of Delphi results into 40 items that the 13 architectural engineering experts may largely agree upon as future prospects with regards to the green architectural engineering. Findings indicate that it is expected that the demand for green architectural engineering and needs for automatic energy control system increase. Also, collaborations with other fields is becoming more and more important in green architectural engineering. The professional work management skills such as knowledge convergence, problem solving, collaboration skills, and creativity linking components from various related areas seem to also be on the increasing need. Near future ready critical skills are found to be the building environment control techniques (thermal, light, sound, and air), the data processing techniques like data mining, energy monitoring, and the control and utilization of environmental analysis software. Experts also agree on new curriculum for green building architecture to be developed with more of converging subjects across disciplines for future ready professional skills and experiences. Major topics to be covered in the near future includes building environment studies, building energy management, energy reduction systems, indoor air quality, global environment and natural phenomena, and machinery and electrical facility. Architectural engineering community should be concerned with building up the competencies identified in this Delphi preparing for fast advancing future.

REVOLUTIONS OF CONSTRUCTION ORGANIZATIONS TOWARDS GREEN BUILDING PRJECTS

  • Po-Han Chen;Yuan-Yuan Li
    • 국제학술발표논문집
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    • The 3th International Conference on Construction Engineering and Project Management
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    • pp.558-565
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    • 2009
  • In recent years, the demand for green buildings is growing fast due to legislative and social pressures. Construction organizations, which play an important role in promoting building industry growth, are facing with challenges on how to adapt themselves to enhance sustainability of the buildings. In this paper, the green value chain and system frameworks, an extend application of Porter's value chain and system models, are introduced. Based on deep analysis of the green value chain and system frameworks, a revolution model for construction organizations towards green building is created. Management factors critical for a successful green building project, at the firm and project organization level, are extracted. Furthermore, external critical relationships are also identified. Fully understanding of these management factors and the model can help and enable practitioner to know what new capabilities should be deployed and developed in the long run for maximizing sustainability.

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소비자의 소비성향과 패션제품 소비태도가 공정무역 패션제품 구매의도에 미치는 영향 (The effect of consumption propensity and fashion product consumption attitude on fair trade fashion product purchase intension)

  • 송예진;신상무
    • 복식문화연구
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    • 제25권5호
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    • pp.656-669
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    • 2017
  • Fair trade implies honest wages and eco-friendly products in keeping with the demands of ethical consumerism. Although consumers are presently more interested in fair trade products, it is hard to find aggressive marketing strategies for fair trade fashion products. Therefore, the purpose of this study investigates the effect of consumption propensity on fast and slow fashion goods consumption attitudes and purchase intention on fair trade fashion products. For method of this study, 229 questionnaires were distributed to consumers residing in Seoul, South Korea. The data from the 219 returned usable questionnaires was analyzed by Cronbach's alpha, factor analysis, regression analysis using SPSS 22.0. The results of this study were as follows: First, consumption propensities of spontaneity, histrionics, and imitative nature in descending order positively affect consumption attitude for fast fashion products. And green consumerism negatively affects consumption attitude for fast fashion products. Second, consumption propensity such as donation & sharing consumerism, ethical consumerism, green consumerism, histrionics, and imitative nature in descending order positively affect consumption attitude for slow fashion products. Third, slow and fast fashion products consumption attitude in descending order positively affect purchase intention on fair trade fashion products. Fourth, consumption propensities such as ethical consumerism, green consumerism, and donation & sharing consumerism in descending order positively affect purchase intention on fair trade fashion products. Therefore fair trade fashion products with various usages and sustainable high quality are promoted by differentiated marketing strategies.

Nanoscale quantitative mechanical mapping of poly dimethylsiloxane in a time dependent fashion

  • Zhang, Shuting;Ji, Yu;Ma, Chunhua
    • Advances in nano research
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    • 제10권3호
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    • pp.253-261
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    • 2021
  • Polydimethylsiloxane (PDMS) is one of the most widely adopted silicon-based organic polymeric elastomers. Elastomeric nanostructures are normally required to accomplish an explicit mechanical role and correspondingly their mechanical properties are crucial to affect device and material performance. Despite its wide application, the mechanical properties of PDMS are yet fully understood. In particular, the time dependent mechanical response of PDMS has not been fully elucidated. Here, utilizing state-of-the-art PeakForce Quantitative Nanomechanical Mapping (PFQNM) together with Force Volume (FV) and Fast Force Volume (FFV), the elastic moduli of PDMS samples were assessed in a time-dependent fashion. Specifically, the acquisition frequency was discretely changed four orders of magnitude from 0.1 Hz up to 2 kHz. Careful calibrations were done. Force data were fitted with a linearized DMT contact mechanics model considering surface adhesion force. Increased Young's modulus was discovered with increasing acquisition frequency. It was measured 878 ± 274 kPa at 0.1 Hz and increased to 4586 ± 758 kPa at 2 kHz. The robust local probing of mechanical measurement as well as unprecedented high-resolution topography imaging open new avenues for quantitative nanomechanical mapping of soft polymers, and can be extended to soft biological systems.

패스트 푸드 선호도에 따른 식생활 행동에 관한 연구 -광주지역 초등학교 6학년을 중심으로 - (A Study on Dietary Behavior of Children According to the Their Preferences for Fast Food)

  • 이성숙
    • 대한지역사회영양학회지
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    • 제9권2호
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    • pp.204-213
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    • 2004
  • The purpose of this study was to examine the dietary behavior of children according to their preference for fast food. The study was carried out on 470, 6th grade students (boys : 236, girls : 234) in September, 2002. The results are summarized as follows : The mean body mass index was 18.72 kg/$m^2$ for boys and 17.76 kg/$m^2$ $^2$ for girls. The subjective health disorder symptoms for the group preferring fast food was not significantly different than that of the other groups. The group preferring fast food consumed an inadequate volume of food, and they had an irregular and unbalanced diet. Their intake of green vegetables, vegetables, protein foods, and seaweed was significantly lower than that of the other groups. The food habit score for the group preferring fast food was lower than that of the other groups, and they had irregular meal times and had unbalanced diets. The group preferring fast food had a preference for sweet tastes, whilst members of the other group preferred a savory taste. The first choice for fast food by the group preferring fast food was hamburgers, the reason being that it tasted good. Results show that children who have a preference for fast food need to correct their dietary behavior. As a result, proper nutritional education and intervention is required in order to improve the consuming habits of children and their preference for fast food.

Solubilities of Salen Derivatives and Their Cobalt Complex in Liquid and Supercritical CO2

  • Koh, Seung-Hyun;Jeon, Byung-Wan;Kim, Ha-Kwon;Park, Kwang-Heon;Kim, Hong-Doo
    • Bulletin of the Korean Chemical Society
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    • 제25권4호
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    • pp.471-475
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    • 2004
  • The solubility of N,N'-Bis(salicylidene) ethylenediamine (n-salen) and N,N'-bis(3,5-di-tert-butylsalicylidene) ethylenediamine (t-butyl-salen) was studied with in-situ UV-VIS spectrometer. n-Salen is 3-5 times more soluble than t-butyl-salen in liquid or supercritical $CO_2$. This behavior may be attributed to Lewis acid-base interaction between salen and $CO_2$. The chelation of salen with $Co^{++}$ ion in supercritical condition was confirmed to be fast enough above room temperature. However, the metal ion extraction capability of t-butyl salen is relatively poor because of its low solubility and ionic nature of complex.