• Title/Summary/Keyword: impact property

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Mechanical and Morphological Properties of Poly(acrylonitrile-butadiene-styrene) and Poly(lactic acid) Blends (아크릴로니트릴-부타디엔-스티렌 공중합체와 폴리유산과의 블렌드에 대한 기계적 물성 및 모폴로지)

  • Lee, Yun Kyun;Kim, Ji Mun;Kim, Woo Nyon
    • Korean Chemical Engineering Research
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    • v.49 no.4
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    • pp.438-442
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    • 2011
  • Mechanical and morphological properties of poly(acrylonitrile-butadiene-styrene) (ABS) and poly(lactic acid) (PLA) blends containing compatibilizers were investigated. Poly(styrene-acrylonitrile)-g-maleic anhydride) (SAN-g-MAH), poly(ethylene-co-octene) rubber-maleic anhydride (EOR-MAH) and poly(ethylene-co-glycidyl methacrylate) (EGMA) were used as compatibilizers. Mechanical properties such as tensile, flexural and impact strengths of ABS/PLA (80/20, wt%) blends were found to be increased when the SAN-g-MAH, EOR-MAH and EGMA were used. The maximum values for mechanical properties of the ABS/PLA (80/20) blend were observed when SAN-g-MAH was used as a compatibilizer at the concentration of 3 phr. From morphological studies of the ABS/PLA (80/20) blends, PLA droplet size was decreased by the addition of the compatibilizers used in this study. From the results of mechanical and morphological properties of the ABS/PLA (80/20) blends, SAN-g-MAH (3 phr) was found to be the most effective compatibilizer among the compatibilizers used in this study.

The impact of technology acquisition strategy on firm performance in Korean Medium size Enterprises (중견기업의 기술획득전략이 성과에 미치는 영향)

  • Hyun, Yong Soo;Lee, Byung Heon;Lee, Jin Seek
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.8 no.3
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    • pp.1-16
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    • 2013
  • The purpose of study is to promote the development of medium size enterprises(MSE) by analyzing the causal relationship between technology acquisition strategy and firms' performance. In this study, we use the number of intellectual property, sales growth rates, and return on sales as proxy variables of technological and financial performances. This study includes internal R&D investment, cooperative R&D with academy, foreign technologies transferred, and their interaction effects as the independent variables. The results of study are as follows. Frist, R&D Investment, Foreign Technologies Transferred and their interaction effects are positively influence on technological performance. Second, Cooperative R&D with academy and the interaction effects of R&D Investment and Cooperative R&D with academy are negative influence on technological performance. On the other hand, all of the main independent variables and the interaction effects have non-significant relationships with financial performances. These results imply that technological innovation efforts of MSEs do not effectively increase their financial performances. Furthermore, technological supports of government and academy on MSEs' innovation do not effectively increase their innovation outputs. Finally, this study discussed its theoretical and practical implications and the limitations of the study.

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An Experimental Analysis for System Optimization to Reduce Smoke at WOT with Low Volatile Fuel on Turbo GDI Engine (저 기화성 연료를 사용한 직접분사식 과급 가솔린엔진에서 전 부하 스모크 저감을 위한 시스템 최적화에 관한 연구)

  • Kim, Dowan;Lee, Sunghwan;Lim, Jongsuk;Lee, Seangwock
    • Transactions of the Korean Society of Automotive Engineers
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    • v.23 no.1
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    • pp.97-104
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    • 2015
  • This study is a part of the high pressure injection system development on the Turbo GDI engine in order to reduce smoke emission in case of using the low volatile(high DI) fuel which is used as normal gasoline fuel in the US market. Firstly, theoretical approach was done regarding gasoline fuel property, performance, definition of particle matters and its creation as well as problems of the high DI fuel. In this experimental study, 2L Turbo GDI engine was selected and optimized system parameter was inspected by changing fuel, fuel injection mode (single/multiple), fuel pressure, distance between injector tip and combustion chamber, start of injection, intake valve timing in engine dyno at all engine speed range with full load. In case of normal gasoline fuel, opacity was contained within 2% in all conditions. On the other hands, in case of low volatile fuel (high DI fuel), it was confirmed that the opacity was rapidly increased above 5,000 rpm at 14.5 ~ 20 MPa of fuel pressure and there were almost no differences on the opacity(smoke) between 17 MPa and 20 MPa fuel pressure. According to the SOI retard, smoke decrease tendency was observed but intake valve close timing change has almost no impact on the smoke level in this area. Consequently, smoke decrease was observed and 16% at 6000rpm respectively with injector washer ring installed. By removing injector washer to make injector tip closer to the combustion chamber, smoke decrease was observed by 46% at 5,500 rpm, 42% at 6,000 rpm. It is assumed that the fuel injection interaction with cylinder head, piston head, intake and exhaust valve is reduced so that impingement is reduced in local area.

Seasonal Characteristics of Pore Development and Hydraulic Properties of Surface Soil in Two Forested Watershed (두 산림유역의 표층 토양의 공극 발달과 수리학적 성질의 계절적 특성)

  • Joo, Sung-Hyo;Gwak, Yong-Seok;Kim, Su-Jin;Kim, Joon;Kim, Sang-Hyun
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.11 no.4
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    • pp.151-161
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    • 2009
  • Configuration of soil hydraulic property is an essential component to understand the hydrological processes at the hillslope scale. In this study, we investigated temporal variations in pore development and soil hydraulic properties during the period from March to October in 2008. Characteristics for macropore flow and hydraulic conductivity were measured at two hillslopes: one is the hillslope located at the Buprunsa in Sulmachun watershed, and the other is the hillslope located in Gwangneung Research Forest. Vertical fluxes through macropore were measured using a tension infiltrometer at the depth of surface. The saturated hydraulic conductivities in March, June, July and September were relatively high compared to those in May and October. Temporal variations in several soil hydraulic features could be explained by the differences in vegetation activity and soil moisture content determined by antecedent precipitation. Particularly, the features of macropores had a substantial impact on hydraulic conductivity in the forest hillslope. The temporal nonuniformity of the soil hydraulic properties observed in this study manifests the dynamic features of hydrological processes in the hillslope scale and the experimental results will be useful to understand the internal hydrological processes in the mountainous hillslope.

Development of Evaluation Method for Environmental Friendly Property in National Highway (일반국도의 환경친화성 평가방법론 개발)

  • Jeon, Woo-Hoon;Lee, Young-Ihn
    • International Journal of Highway Engineering
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    • v.12 no.3
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    • pp.87-92
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    • 2010
  • As the Concept "how environmental friendly" becomes more and more important in road construction. However, so far there is no estimation method. Environmental friendly concept can be incorporated at the plan level in order to influence decision making, and support policies that affect environment. The overall goal of this study was to develop environmental friendly concept measures for the national highway and to develop a methodology to implement a more environmental friendly concept. The research identified 8 performance measures through a project analysis that could address environmental impact assessment system's ten strategic goals - Topography, Wildlife, hydrology, landuse, air quality, water quality, soil, waste, noise, landscape. The qualitatively and quantitatively evaluation approach was selected as the decision support framework and performance measure were investigated using the AHP(Analytic Hierarchy Process) and pilot corridor for a 10 section and calculate the index values. The methodology was applied to a pilot corridor comprised of a 120km section of national highway in korea. The methodology made it possible to identify the specific performance measures that need improvement to enhance the overall environmental friendly concept. It is fairly intuitive, based on readily available data, and is easy to apply. It provides a powerful tool for government to assess the relative environmental friendly conceptof their transportation corridors now and in the future. It allows for comparisons within a corridor and with other corridors and identifies the improvements needed to enhance the environmental friendly concept.

An Experimental Study on the Thermal Property of Concrete under the Load Ratio Condition in Fire (화재시 하중재하에 따른 콘크리트의 열적특성에 관한 실험적 연구)

  • Kim, Hyung-Jun;Kim, Heung-Youl;Park, Kyung-Hun;Jung, Jae-Young;Kwan, Ki-Hyuk
    • Fire Science and Engineering
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    • v.23 no.6
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    • pp.66-74
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    • 2009
  • When a fire occurs, the concrete structure's strength decreases by the increasing temperature under the fire in certain condition of constant load. And, the ratio of the axial force is changed by such decreased strength so that the structure is deformed. In this research, considering such case, we have conducted an actual fire test for the concrete lining with constant loading condition and various fire conditions. The specimen adopts the shape condition for small practical specimen defined by the EFNARC and we used 24MPa, 40MPa and 50MPa to analyze the thermal properties by the strength. The ratio of loading is imposed by a certain loading condition based on 20% and 40% of the sectional stress in concrete and MHC Fire is selected to realize the thermal impact of the concrete by rapid increasing temperature. As the result of the experiment, in the same ratio of loading, the 50MPa specimen shows more cracks and spalling as time goes on. The area damaged by the fire, according to the functional criteria of the concrete lining under the fire in ITA, does not satisfy with the standard in lack of 50mm depth from the heating surface at total 200mm lining.

A Study on Analysis of Factors Affecting Technology Transfer Performance of Universities : An Approach to Different Types of Korean Universities (대학의 기술이전성과 영향요인 분석 : 대학의 유형별 접근)

  • Lee, Chang-Hak;Lee, Cheol-Gyu;Lee, Dong-Myung
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.12 no.9
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    • pp.3936-3951
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    • 2011
  • This paper aims to analyze factors affecting technology transfer performance according to different types of Korean universities and to conduct the research for the channel and extent of impact between these factors, utilizing 5 - year data for the technology transfers of 110 universities based on the survey by National Research Foundation of Korea. According to the analysis, incentive for researchers is the most crucial factor in local universities and small & medium-sized private universities located in the capital area. And numerical value of intellectual property rights owned by university is the key factor in universities specializing in science & engineering / industry. Also, Big-sized universities are heavily affected by the number of full-time faculty. In case of private universities, government subsidy relating to patents is critical factor for technology transfer performance. The mean value of all variables is a lot higher in participant universities than non-participant ones in CK(Connect Korea) project. In summary, it is suggested that steady financial support provided by the government is required and that mutual cooperation for industry-university-government is also needed for the commercialization of the technologies held by universities.

The Effects of Technology Commercialization Activities on the Business Performance: Case study of basic science and technology of public research institutes transferred to enterprises (기술사업화 활동이 기업의 경영성과에 미치는 영향: 기업으로 이전된 공공연구기관의 기초·원천기술을 중심으로)

  • Jeong, Myoung-Sun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.4
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    • pp.418-427
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    • 2017
  • In Korea, interest in basic research is growing, in order to ensure the sustainable competitiveness of the main industries and to support world-class technology that can create high added value in the future. However, companies are known to encounter various problems when attempting to market products based on the results of basic research, which is known to be due to their lack of experience of commercialization and related activities. Therefore, in this study, we tried to analyze the effect of the technology commercialization activity stemming from basic science and technology research on the business performance. The technology commercialization activities are divided into experience of commercialization, complete charge department, and consulting on technology commercialization and we developed an analytical model that (distinguishes between?) the technology innovation activities and technology innovation capabilities and analyzed their impact on the business performance. As a result, the importance of technology commercialization activities was confirmed by the fact that it had a positive effect on the business performance, while the technological innovation activity was found to positively affect the management performance, demonstrating that it plays a strategic role in companies. Finally, it was found that the technology innovation capacity partially influences the management performance and that it is necessary to establish a strategic research and development infrastructure.

A Study on the Peak Runoff Reduction Effect of Seolleung·Jeongneung Zone by Applying LID(Low Impact Development) System based on the Landscape Architectural Technology (조경기술기반 LID 시스템 적용을 통한 선릉·정릉 권역의 첨두유출량 분석)

  • Kim, Tae-Han;Choi, Jong-Hee
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.35 no.4
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    • pp.126-133
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    • 2017
  • This study analyzed hydrological changes of stormwater runoff of Seolleung Jeongneung zone according to the application of LID system based on landscape Architectural technology. The results are as follows. First, when flooding occurred in Gwanghwamun in July 27, 2011, the maximum instantaneous rainfall amount was 183 mm/hr recorded at 10:00 on 27th for 10 minutes, and it was confirmed that rainfall intensity more than three times as high as the maximum rainfall of 57.5 mm/hr. Second, it is possible to control peak flow rate in the case of 1,500mm of soil thickness, so that it is possible to improve the vulnerability of flood damage in Seolleung and Jeongneung zone when applying the LID system. Third, in the berm height scenario, peak flow rate control was not controled in all depth level models, but the first stormwater runoff was delayed by 4 hours and 10 minutes compared to the soil thickness scenario. It was interpreted as a relatively important indicator the soil thickness for the initial stromwater runoff reduction and the berm height for the peak runoff. Through this, the systematic adaptation of landscape-friendly ecological factors within the cultural property protection zone could theoretically confirm the effects of flood disaster prevention.

Applicability of Composite Polyurea Method Considering the Required Performance in Underground Parking Lot Upper Slab (공동주택 지하주차장 상부슬래브의 요구성능을 고려한 복합형 폴리우레아 공법의 적용성 검토)

  • Lee, Jung-Hun;Choi, Eun-Kyu;Song, Je-Young;Kim, Soo-Yeon;Oh, Sang-Keun
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.7 no.3
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    • pp.243-254
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    • 2019
  • In this study, problems of the waterproofing methods in which water leakage occurs in the upper slab of the underground parking lot of apartment houses and the requirements considering the characteristics of the upper slab, and selected the appropriate performance(proposal) for the composite polyurea process are reviewed. As a result of the study, it is necessary to review performance such as responsiveness to upper slab of the multi-unit underground parking lot that is comprised of (1) crack and behavior responsiveness, (2) surface integrity, (3) vertical watertight stability, (4) pressure layer construction, (5) impact and pressure response and (6) vehicle moving load. As a result of evaluating 5 items corresponding to the requirements for the soft and hard complex polyurea, all of them were found to meet the conditions, and each materials were improved by compounding the materials that had problems when applying a single-ply method, thereby clarifying the advantages and disadvantages of the material property. However, in order to apply to the actual site, additional evaluation on site applicability such as mock-up evaluation should be conducted, and subsequent studies on the applicability of the market through review of economic feasibility and maintenance is required.