• Journal of the Korean Society of Propulsion Engineers
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• v.4 no.3
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• pp.45-54
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• 2000

Ignition transient is a. very rapid process lasting only in the order of 100 milliseconds and therefore it is difficult to measure all relevant ballistic properties. Numerical simulation is thus useful to quantify some of these hard to measure flow and ballistic properties. One-dimensional model was employed to study the effects of aging using simplified aging scenarios for both N-H sustainer and booster motors. Also the effects of newly designed igniter on the ignition of N-H sustainer was simulated. Radiation effects could be significant in terms of energy flux increase to the propellant surface and the energy exchange between the combustion gas itself. One dimension implementation of radiation showed significant effects for rear-mounted igniter. Implementation of radiation effects into 2-D axi-symmetric numerical model was completed and its effects on the N-H sustainer were examined. To have a reliable prediction of computer model on ignition transient, accurate chemical property data on the propellant and igniter gas are required. It was found that such property data on aged N-H motors are not available. Chemical aging model can be used to predict to some degree of accuracy effects of aging on chemical and mechanical properties. Such a model was developed, albeit 2-dimensional, to study migration of moisture through a representative solid rocket motor configuration.

• Advances in materials Research
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• v.11 no.3
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• pp.191-209
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• 2022

Very slow degradation of synthetic based polymers has created a severe environmental issue that increased awareness towards research in polymers of biodegradable property. Soy protein isolate (SPI) is a natural biopolymer used as matrix in green composites but it has limitations of low mechanical properties and high water sensitivity. To enhance mechanical properties and reduce water sensitivity of Jute-SPI composites, SPI was modified with pine rosin which is also a natural cross-linking agent. 30% glycerol on the weight basis of a matrix was used as a plasticizer. The fibre volume fraction was kept constant at 0.2 whereas the pine rosin in SPI ranged from 5% to 30% of the matrix. The effects of pine rosin on mechanical, thermal, water sensitivity and surface morphology have been characterized using various techniques. The mechanical properties and water absorbency were found to be optimum for 15% pine rosin in Jute-SPI composite. Therefore, Jute-SPI composite without pine rosin and with 15% pine rosin were chosen for investigation through characterization by Fourier transforms infrared spectroscopy (FTIR), Thermo-gravimetric analysis (TGA), X-Ray diffraction (XRD) and Scanning electron microscope (SEM). The surface morphology of the composite was influenced by pine rosin which is shown in the SEM image. TGA measurement showed that the thermal properties improved due to the addition of pine rosin. Antimicrobial test showed antimicrobial property in the composite occurring 15% pine rosin. The research paper concludes that the modification of SPI resin with an optimum percentage of pine rosin enhanced mechanical, thermal as well as water-resistant properties of jute fibre reinforced composites.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.8 no.1
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• pp.29-36
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• 2013

So many researchers have been interested in key success factors of technological start-ups. However, previous studies have not focussed on Concreteness of technological capabilities at the growth stages and industry in technological start-ups. The purpose of this study is to investigate the Concreteness of technological capabilities that have influence on performance of technological start-ups. Empirical data was collected from 342 firms in BI in Korea. It used the questionnaire method for the CEO, It is executed the Regression analysis to test hypotheses of influencing effects. Results of the hypothesis testing are summarized as follows: First, It was found that technological capabilities had statistically significant influence on firm performance. But the property based resources had lower significant influence. Second, This research found that the knowledge based resources had higher significant influence on technological start-ups performance at IT industry. Third, The knowledge based resources had higher significant influence on performance at growth stages. In conclusion, technological capabilities were verified as important firm resources of technology-based start-ups for firm performance. But the Concreteness of technological capabilities was significant differences by growth-stage of firms.

• Journal of Science and Technology Studies
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• v.11 no.1
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• pp.31-59
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• 2011

This paper examines university patenting activities as a commercialization of academic research. It shows how a number of university patents increase exponentially and how that can be, especially in terms of role of the state. In the late 1990, the Korean government supports the new vision of 'technological innovation' in establishing a science and technological policy and begins to perceive the importance of university R&D to overcome the economic crisis. Thus, an administrative, financial, and legal systems which support the university R&D are organized and the governmental grants for R&D increase exponentially, especially in promising new technologies(6T). Also, an institution for managing intellectual property rights is established in university. Universities assess professor's performance in terms of patent and license to encourage patenting activities. Thus the number of patents and its productivity increase exponentially. But the increase in patents takes place only to a dozen of universities, this means that a Matthew effect does work.

• Journal of Technology Innovation
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• v.22 no.4
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• pp.117-143
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• 2014

Tracing an evolutionary technological trajectory in the macroscopic viewpoint is useful for technology policy, but not for corporate technology and intellectual property strategy. Tackling this issue, recent bibliometric studies using patents and papers have made efforts to identify more specific and detailed technological trajectory. However, these studies cannot go beyond simple description of the past trajectory. Also, identification of technology fusion and evolution relies on experts judgments. We suggest a way of identifying microscopic evolutionary technological trajectories by combining patent citation network analysis with dynamic technology tree. Also, using new indicators of generality, diversity and novelty, we can detect key technologies that can be a starting point of next generation technology and derivative technology. HVDC(High Voltage DC transmission) system technology is exemplified.

• Proceedings of the Technology Innovation Conference
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• 1996.12a
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• pp.265-295
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• 1996

This paper investigates empirically the relationship between various business portfolio properties (particularly technological properties) and chaebol′s performance using data on the 50 largest chaebols in Korea. In addition to the traditional indexes to measure diversification such as entropy index we calculated inter-industry technological similarity using R&D expenditure data by industry and 1990 Input-output Table in Korea, and obtained chaebol-level technological relatedness and internal transaction proportion from chaebols′business profile, inter-industry technological similarity and 1990 input-output table. We applied factor analysis on 13 business portfolio property indexes and showed that they could be grouped into 3 dimensions, diversification scope, inter-business relatedness and degree of vertical integration. In this paper, using 50 largest chaebols′financial data (1989-1994), we analyzed empirically the effect of business portfolio properties on ROS (Return On Sales) which is conventional index for firm performance and on TFP(Total Factor Productivity) growth which is a pure measure of firm performance. To utilize the advantage of panel data, FEM(Fixed Effect Model) and REM(Random Effect Model) were used. The empirical result shows that the entropy index as a measurement of inter-business relatedness is not significant but technological relatedness index is significant. OLS estimates on pooled data were considerably different from FEM or REM estimates on panel data. By introducing interaction effect among the three variables for business portfolio properties, we obtained three findings. First, only VI (Vertical integration) has a significant positive correlation with ROS. Second, when using TFP growth as an dependent variable, both TR(Technological Relatedness) and f[ are significant and positively related to the deepened variable. Third, the interaction term between TR and VI is significant and negatively affects TFP growth, meaning that TR and VI are substitutes. These results suggest strategic directions on restructuring business portfolio. As VI is increased, chaebols will get more profit. A higher level of either TR or W will increase TFP growth rate. but increase in both TR and VI will have a negative effect on TFP growth. To summarize, certain business portfolio properties such as VI and TR can be considered "resources" themselves since they can affect profit rate and productivity growth. VI and TR have a synergy effect of change in profit rate and productivity growth. VI increases ROS and productivity growth, while TR increases productivity growth representing a technological synergy effect.

• Journal of Information Technology Applications and Management
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• v.21 no.4_spc
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• pp.331-344
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• 2014

This study attempts to explore the difference of innovation sources between high-tech industry and mid-tech industry through patent analysis. After extracting 119 corporates, commonly surveyed in 2007 HCCP(Human Capital Corporate Panel) and 2005~2006 Korea Innovation Survey, their patents applied for the Korean Intellectual Property Office in 2007~2012 are analysed mainly through negative binomial regression model. Analytical results shows that external information source could be opposite effects to technological innovation depending on technological level and industrial characteristics. The current results are still bounded in the statistical significance, mainly due to the limited observations and information.

• Knowledge Management Research
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• v.11 no.1
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• pp.65-81
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• 2010

This paper explores the determinants of the economic value of patents using a survival time analysis. The analysis is based on renewal information of about 250,000 patents filed from 1984 to 2005 in the Korea Intellectual Property Office. A patent right is valid only when its owner pays yearly maintenance fees. Failure to pay causes patent rights to be lapsed. We use the fact that more valued patents live longer and the lengths of their renewals can be closely related to their value. The value can be affected not only by its own technological aspects such as quality and breadth, but also by characteristics of its owners such as innovativeness and age. This paper presents patent-specific and firm-specific characteristics which influence patent value. The result of analysis implies that patent value depends on both the technological contents of the patent and general capabilities of a firm.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.25 no.2
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• pp.286-293
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• 2021

Smart contract based on the blockchain technology can be applied to the real estate registry including transactions. The Ethereum coin using multi layered protocol is widely accepted as the token for the smart contract. Block chain smart contract using SOLIDITY or PYTHON can mediate transactions auch as sale or lease, creating various scenarios in the property market. Those smart contract can construct the basis for the blockchain real estate registry, which is expected to overcome conventional transaction costs concerning the national law system, the asymmetric information and the currency exchange. The advantages of blockchain technology, namely security, decentralization, global transparency and openness can be applied to the smart contract system on the property registry. Several countries have advanced such blockchain real estate registry project recently, but no actual implementation has been reported for years, owing to institutional and technological impasses.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.13 no.3
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• pp.85-98
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• 2018

This study aims to investigate the effects of venture & inno-biz companies' technological innovation competences on technological performances and economic competitive advantage, using VRIO framework. The empirical data for this study were based on the technology assessment results of Korea Technology Finance Corporation (KOTEC) on 3,462 venture & inno-biz companies and the following 2 years' financial data. Sample companies with technological innovation resources, such as technology management strategy(Value), differentiation of technology(Rarity), imitation difficulty of technology(Imitability) and technical organization capability(Organization), made efforts to expand their intellectual property rights, technological development and commercialization of new products, thereby ensuring technological competitive advantage. Furthermore, technological competitive advantage were proved to improve sales growth, increase in operating revenue, and financial soundness. Compared with four VRIO factors' influence on business performance, imitation difficulty of technology(Imitability) and organization technological capability(Organization) had much more influence than any other internal resources or capabilities respectively.