• The KIPS Transactions:PartA
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• v.18A no.3
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• pp.81-92
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• 2011

There has been a number of attempts to apply 3D CAD data created in the design stage of product life cycle to various applications of the other stages in related industries. But, 3D CAD data requires a large amount of computing resources for data processing, and it is not suitable for post applications such as distributed collaboration, marketing tool, or Interactive Electronic Technical Manual because of the design information security problem and the license cost. Therefore, various lightweight visualization formats and application systems have been suggested to overcome these problems. However, most of these lightweight formats are dependent on the companies or organizations which suggested them and cannot be shared with each other. In addition, product structure information is not represented along with the product geometric information. In this paper, we define a dataset called prod-X3D(Enhanced X3D Dataset for Web-based Visualization of 3D CAD Product Model) based on the international standard graphic format, X3D, which can represent the structure information as well as the geometry information of a product, and propose a translation method from 3D CAD data to an prod-X3D.

• Korean journal of applied entomology
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• v.55 no.3
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• pp.235-243
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• 2016

The winter cherry bug, Acanthocoris sordidus (Thunberg), is an insect pest hat damages plants from Solanaceae and Convolvulaceae. The developmental period from egg to adult averages 76 days at $25^{\circ}C$. Adult egg-laying occurred irregularly via spawning, averaging 195 (up to 468) eggs per individual on the abaxial leaf surface of the host plant. Results of linear regression indicated that the lower developmental threshold temperature was $13.9^{\circ}C$ and the effective accumulated temperature was 526.3 DD. Data from a pepper field in 2015 indicated that overwintering adults first appeared during late June (daily average temperature = $25.7^{\circ}C$), reaching maximum density by early September. A choice test examining colonization preferences using a net cage and a Y-tube olfactometer revealed that females gravitated toward conspecifics (other females, males, or both), whereas males moved toward empty areas. Finally, we found that communal breeding results in a longer developmental period and higher eclosion rates than solitary breeding. Developmental periods and eclosion rates were also for colonies in a large space than for those in a small space. This outcome suggests that colonization effects on insect development are stronger in a smaller area.

• Journal of Korean Society of Steel Construction
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• v.29 no.1
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• pp.49-60
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• 2017

As well as the strength check, fatigue life check is also mainly required for designing mooring lines of the floating structures. In general, forces which induce dynamic structural response significantly affect to fatigue design of the mooring lines. So, waves are mainly considered as the governing loading for fatigue design of the mooring lines. In this study, characteristics of the fatigue damage of the mooring lines for submerged floating tunnels (SFT) under irregular waves are investigated. For this study time domain hydrodynamic analysis is used to obtain motion of the tunnel and tension and stresses of the mooring lines under the specific environmental conditions. Also, the Rainflow-counting method, the Palmgren-Miner's rule, and S-N curves for floating offshore structures presented by DNV recommendation is applied to calculate the fatigue damage due to the fluctuating stresses. Referring to the design plactice of the tendon pipes for TLP (tension-leg platform), which is very similar structural system to SFT, it is assumed that a 100 year return period wave attacks the SFT systems during 48 hours and the fatigue damages due to the environmental loading are calculated. Following the analysis sequence, the effects of the tunnel draft, spacing and initial inclination angle of the mooring lines on the fatigue damage under the specific environmental loadings are investigated.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.15 no.2
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• pp.97-110
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• 2020

This paper is on the policy proposal for venture ecosystem. First, one of the three secrets of the US venture ecosystem is the law of 50:50. Angel capital investment is as important as venture capital investment. Although professional angel investors and accelerators account for as much as VC in the venture ecosystem, they are ignored from policy considerations. We argue that the revision of related law is urgent. Second, large US firms invest more in M&As than in internal R&D. Therefore, accelerators and professional angel investors could make effective investment recovery after investing in a startup company. In other words, angel capital does not come in without secondary market development. Angel capital and secondary markets are the two pillars of the venture ecosystem. The government alone is difficult to develop a secondary market. This is why the private sector should come in and introduce corporate venture capital (CVC). Third, we believe the policy direction for national economic growth should be extended from the startup to scale-up. This is because the startup's sales and job creation will start in five years. While the previous study focused on funding (venture financing), this paper aims to balance all three stages of a venture: startup, growth, and recovery, which are the life cycle of a venture company or venture investment. In particular, we propose specific policies in each chapter to improve practical application.

• Proceedings of the IEEK Conference
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• 1999.11a
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• pp.989-992
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• 1999

Battery로 작동되고, 소형인 제품들도 다양한 기능은 물론이고, 다양한 입출력 장치를 갖추고, 실시간으로 처리하는 시스템이 많이 요구되고 있는 실정이며, 점차 더욱 더 요구될 것으로 전망된다. 더욱이 포터블 기기는 일반적으로 MCU의 내부에 제한된 ROM type 메모리를 내장하게 되면, 데이터 메모리로 SRAM 및 flash memory를 갗추고 있다. 따라서 이러한 제한된 하드웨어 환경하에서 많은 기능을 수행해야 하는 경우가 많다. 여러 기능을 시간적인 간격으로 배분하거나, 기능 자체를 서로 배분하면서, 서로 융합하는 등의 여러 가지 기능을 수행하려다보면, 당연히 메인 소프트웨어 구조가 복잡해지며 대부분 어셈블리나 C와 같은 linear한 구조를 가지는 language로 개발되기 때문에 효과적인 프로그램 구조를 세우기는 쉽지 않다. 본 논문에서는 이를 위해 좀더 규격화된 방법을 제시하고자 한다. 보다 구체적인 구조를 연구할 목적으로 다양한 테스크를 수행하여야 하는 시스템이면서 프로세서가 필요한 포터블 기기의 한 응용 제품인 MP3 Player 에서 요구되는 job scheduling을 연구한다. 필요한 작업의 종류는 가장 부하가 많이 걸리는 압축된 MP3 file을 다시 복원시켜주는 codec 부분과 일정 시간 간격을 가지고 수행하여야 하는 외부 키보드 입력과 실시간으로 시간을 계산하는 타이머 기능, 그리고 LCD에 시간의 변화를 표시하여 주어야한다. 이와같이 수시로 작업이 발생하지만 시간 점유율이 중간 정도인 LCD 컨트롤과 메모리 컨트롤 등이다. 프로세서의 속도를 최소한으로 줄이면서 스케줄링에 의해 시간 문제를 해결하는 방법을 제시하도록 한다. 이는 기초과학 수준이 높은 북방권 국가들의 과학자들이 주로 활용되고 있다는 점에서도 잘 알 수 있으며 우리의 과학기술 약점을 보완하는 원천으로써 외국인 연구 인력이 대안이 되고 있음을 시사한다. 본 연구에서는 한국 연구 조직에서 일하는 외국인 연구자들의 동기 및 성과에 영향을 미치는 많은 요인들을 확인할 수 있었다. 상관관계, 분산분석, 회귀분석 등을 통해 활용 성과에 미치는 영향 요인들을 도출하였다. 설문 분석을 통하여 동기 및 성과 사이에는 강한 상관관계가 존재하는 것을 확인할 수 있었으며 이는 전통적인 동기 이론들과 부합한다. 대부분의 변수가 동기 및 성과에 동시에 영향을 미치는 것으로 조사되었으며 그중에서도 조직 협력 문화, 외국인 연구자의 의사소통 및 협력성, 외국인 연구자의 연구 능력 관련 변수들 및 연구 프로젝트의 기술수명주기, 외국인 연구자의 기존 기술지식의 흡수 등이 가장 중요한 변수로 나타났다. 이는 우리가 주로 중국 및 러시아 과학자들을 활용하여 상업화하는 외국인 연구인력 활용 패턴과도 일치하는 결과이다. 즉 우호적인 조직문화를 가지고 있는 연구 조직에서, 이미 과학기술 지식을 많이 가지고 있고 연구 능력도 높은 외국인 과학기술자를, 한국에서 기술이 태동 또는 성장하고 있는 연구 분야에서 활용하는 것이 가장 성과가 좋다는 사실을 확인시켜 주고 있다. 국내에서 최초로 수행된 본 연구는 외국인 연구 인력의 활용 성과가 매우 높으며, 우리의 과학기술혁신시스템을 보완하는 유효한 수단으로써 외국인 연구 인력이 중요한 대안이 될 수 있음을 발견하였다. 외국인 연구 인력을 잘 활용하기 위하여 문제점 및 개선방안을 활용 환경, 연구 인력이 중요한 대안이 될 수

• KSCE Journal of Civil and Environmental Engineering Research
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• v.35 no.2
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• pp.481-491
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• 2015

Since the crack in the surface of the concrete acts as the main reason influencing the life span of the structure, regular inspections and maintenance are required. The sealing required for maintenance of the concrete surface is a method of repairing the crack in the surface in the beginning, and is effective in preventing additional cracks and expansion that occurs with time. However, sealing on large sized structures such as tall buildings or bottom parts of bridges are difficult to ensure safety of the workers due to inadequate working environments. Due to this reason, the importance of the need for sealing automation for the maintenance of large sized concrete structures is emerging. This study proposes two control methods to apply robot systems to the sealing of cracks on the bottom parts of concrete bridges. First is the method of automatically tracking the trajectory of cracks. The robot gets the trajectory of the cracks using video information obtained from cameras. Comparing the previous several points and new point, the next point can be estimated. Thus, the trajectory of the crack can be tracked automatically. The other method is sealing by maintaining steady force to the contacting surface. The concrete surface exposed to an external environment for a long time gets an irregular roughness. If robots are able to carry out sealing while maintaining a steady contact force on these rough surfaces, complete equal sealing can be maintained. In order to maintain this equal force, a force control method using impedance is proposed. This paper introduces two developed control methods to apply to sealing robots, and conducts a Lab Test and Field Test after applying to a robot. Based on the test results, opinions on the possibilities of field application of the robot applied with the control methods are presented.

• Journal of the Korea Institute of Building Construction
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• v.10 no.5
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• pp.55-67
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• 2010

The main purpose of this study is to develop a system and data model extracted from the TO-BE process model of rental apartments to promote information exchange based on knowledge obtained through maintenance status analysis. Currently, it is difficult to find examples suggesting a data model through a process analysis of maintenance in rental apartments. Thus, this study intends to suggest a process as well as a data model to promote the development of a maintenance system for rental apartments by using building management knowledge, utilization of standardized tools, and existing FM (Facility Management) techniques to break through limitations in actual application. Ultimately, this study aims to show examples of document-oriented analysis and information technology for middle managers in charge of the maintenance of rental apartments, as well as work analysts developing the maintenance system. In further research beyond this study, complex issues on the maintenance of rental apartments, legal restrictions on customary practices of maintenance activities, effects of the scales of maintenance practices, requirements to perform maintenance activities, evaluation on the status of maintenance, life cycle cost and risks will be investigated.

• Journal of the Korean Recycled Construction Resources Institute
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• v.1 no.1
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• pp.42-48
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• 2013

The present study assessed the amount of $CO_2$ uptake owing to concrete carbonation through a case study for an apartment building with a principal wall system and an office building with Rahmen system under different exposed environments during use phase and recycling application. The $CO_2$ uptake assessment owing to concrete carbonation followed the procedure established by Yang et al. As input data necessary for the case study, actual surveys conducted in 2012 in Korea, which included data about the climate environments, $CO_2$ concentration, lifecycle inventory database, life expectancy of structures, and recycling activity scenario, were used. From the comparisons with the $CO_2$ emissions from concrete production, the $CO_2$ uptake during the lifetime of structures was estimated to be 5.5~5.7% and that during recycling activity after demolition was 10~12%; as a result, the amount of $CO_2$ uptake owing to concrete carbonation can be estimated to be 15.5~17% of the $CO_2$ emissions from concrete production, which roughly corresponds to 18-21% of the $CO_2$emissions from cement production as well.

• Journal of Distribution Research
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• v.15 no.5
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• pp.195-215
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• 2010

Large-scale discount stores, that were in charge of leading role up to recently, reach the limit of growth because of increasing competition, saturation of domestic market, and shortened product life-cycle. As per the limit of domestic market, large-scale discount stores are trying to various global market entry strategy and global marketing strategy like new store entry, takeover of foreign distribution chain, and global sourcing strategy. In the past, global companies of advanced country have been entering to Asian market with leading position. But, as per the rapid growth of Asian economy in the late 1980's, East Asian distribution companies like Japanese company were trying to enter the Asian market. In Asian market, starting with China, that was relatively not advanced in comparison with economic development, not only western advanced countries but also East Asian countries like Japan and Korea are entering actively for overcome their limitations of domestic market. Many of distribution companies experienced success and failure for various reason already. Korean large-scale discount stores are relatively late starters in Asian market. So, this paper purposed to review global market entry strategy of Japanese large-scale discount stores, and find out strategic implications for successful global market entry strategy of Korean large-scale discount stores.

• International Journal of Highway Engineering
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• v.7 no.3 s.25
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• pp.1-10
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• 2005

In this study, accelerated pavement tester(APT) was performed on long-life asphalt pavements that can save maintenance and user costs by increasing the design life twice longer than conventional asphalt pavements. Basic material testings are first conducted on a high modulus base(HMB) mixture developed in this study. Four different pavement sections including thin and thick conventional and thin and thick HMB courses are constructed to compare the load-carrying capacities and to investigate the fatigue and rutting performances using an accelerated pavement tester. Tensile strain values at the bottom of base courses under the various loading levels are measured. The tensile strain values of the HMB sections are lower than those of the conventional sections. It is observed from the APT performed on the thin pavement sections that no significant cracks are developed up to the 180,000 cycles of a wheel load. In terms of rutting, only 3mm of rutting is developed in the thick HMB section while 5.3mm of rutting is developed in the thick conventional section at the 90,000 cycles of the wheel load. The HMB material developed in this study can be successfully used in the long-life asphalt pavements because of its excellent fatigue and rutting performances. It is estimated from a series of structural analysis that the use of the HMB material instead of the conventional base materials may reduce the asphalt thickness at least 5cm because of its better load-carrying capacity.