• Title/Summary/Keyword: Fast Green

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

  • 이관영;강호양;정성호;정두진
    • Journal of the Korea Furniture Society
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    • v.11 no.1
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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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    • v.7 no.2
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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.

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

  • Kim, Eui-Joong
    • Proceedings of the Korea Electromagnetic Engineering Society Conference
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    • 2002.11a
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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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Comparative Study on the Green Speed by different the Types of Putting green Maintenance Equipment (퍼팅그린 관리 장비 유형에 따른 그린스피드 차이 비교)

  • 장유비;심경구
    • Asian Journal of Turfgrass Science
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    • v.18 no.1
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    • pp.37-46
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    • 2004
  • The purpose of this study is to find the suitable putting green maintenance equipment for improving the quality of putting green. This study was carried out to investigate the green speed(i.e., ball roll distance) by different the types of greens mower(between work-behind greens mower and riding greens mower), the types of reel blades(between 9 blades and II blades) and the types of roller(between riding soil sprayer and lightweight roller). Green speed of golf course putting greens is assessed by use of Stimpmeter. The west course of Lakeside Country Club was selected for the case study. The results are summarized as follows; 1. The green speed was faster in 3.8 mm moving height treatment plot using work-behind greens mower than in 3.8 mm moving height treatment plot using riding greens mower right after the moving and even after eight hours had passed, and it was statistically significant at a 95% confidence level. Therefore, work-behind greens mower was judged to be a proper equipment type for the fast green management practice than riding greens mower. 2. The green speed was faster in 3.2 mm mowing height treatment plot using work-behind greens mower equipped with II blades than in 3.2 mm mowing height treatment plot using work-behind greens mower equipped with 9 blades, and this result was statistically significant at a 95% confidence level. Therefore, II-blade was judged to be a proper blade type for the fast green management practice than 9-blade. 3. The difference in green speed (green speed increased after rolling) between a treatment plot mowed at 3.0 mm mowing height with the work-behind greens mower and then rolled a single time with riding soil sprayer and a treatment plot mowed at 3.0 mm mowing height with the work-behind greens mower and then rolled once with lightweight roller was not statistically significant at a 95% confidence level. However, the difference in green speed (green speed decreased after rolling) between two treatment plots measured after eight hours had passed was statistically significant at a 95% confidence level. Therefore, the lightweight roller was judged to be a proper roller type for the fast green management practice than the riding soil sprayer.

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

  • Kang, So Yeon;Kim, Taeyeon;Lee, Jungwoo
    • Journal of Engineering Education Research
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    • v.21 no.3
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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
    • International conference on construction engineering and project management
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    • 2009.05a
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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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The effect of consumption propensity and fashion product consumption attitude on fair trade fashion product purchase intension (소비자의 소비성향과 패션제품 소비태도가 공정무역 패션제품 구매의도에 미치는 영향)

  • Song, Ye Jin;Shin, Sangmoo
    • The Research Journal of the Costume Culture
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    • v.25 no.5
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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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    • v.10 no.3
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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.

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

  • 이성숙
    • Korean Journal of Community Nutrition
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    • v.9 no.2
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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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    • v.25 no.4
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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.