• International Journal of Aeronautical and Space Sciences
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• v.3 no.1
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• pp.19-29
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• 2002

Decentralized filtering for a formation flight instrumentation system by INS/GPS integration is considered in this paper. An elaborate tuning method of the measurement noise covariance is suggested to compensate modeling errors caused by decentralizing the extended Kalman filter. It does not require large data transfer between formation vehicles. Covariance analysis exhibits the superior performance of the proposed approach when compared with the existent decentralized filter and the global filter, which has the target-filter performance.

• Asia-Pacific Journal of Business
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• v.3 no.1
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• pp.29-38
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• 2012

This study aims at evaluating the impact of network formation variables and found to have positive impact on the economic performance and growth of the enterprises. The calucation of the weighted scores of networking statements brought some affirmative results to influence the performance of the enterprises. Through multiple regression and logistic regression models it is identified that network formation variables like service receiving status, consultation of the family, other business dummy and attendance in fair have some significant positive impact both on the growth and performance of the enterprises. In addition to above variables, from the set of enterprise characteristics natural logarithm of the market value of total assets and from the entrepreneurs' characteristics set of variables, schooling year and squared value of the experience have been found to have significant positive impact. Finally, it is concluded in the study that to enhance the performance and growth of the enterprises, government and policy rlated organizations need to consider important variables that have positive impact in supplying the entrepreneurial resources especially, developing the net-working relationship.

• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.515-518
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• 2007

Gas hydrates are ice-like crystalline compounds that form under low temperature and elevated pressure conditions. Recently, gas hydrates present a novel means for natural gas storage and transportation with potential applications in a wide variety of areas. An important property of hydrates that makes them attractive for use in gas storage and transportation is their very high gas-to-sol id ratio. In addition to the high gas content, gas hydrates are remarkably stable. The main barrier to development of gas hydrate technology is the lack of an effective mass production method of gas hydrate in solid form. In this study, some performance comparison among several cases classified by different volume sizes of solution were carried to identify the characteristics due to the volume increment. And it is found that one of the main reasons disturbing hydrate formation is related to the lack of cooling heat transfer due to the volume increase of the solution. So, three kinds of heat transfer plates which have different shapes and cross sectional areas were made and tested for the performance comparison following to the shape and area of each plate. Finally it is clarified that the heat transfer is one of the major factors effecting hydrate formation performance and the installation of heat transfer plate can enhance the formation performance especially not in terms of the quantity but the speed.

• International Journal of Advanced Culture Technology
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• v.7 no.2
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• pp.93-102
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• 2019

This study is to examine the effects of business management competency, organizational management competency, relationship formation competency, marketing competency, and entrepreneurship, which are perceived by organizational members of social enterprise, on organizational performance, economic performance and social performance. The results of this study are as follows. First, the business management competency of the executives influencing the economic performance, which is the organization performance of the hypothetical social enterprise, was adopted. In other words, the organizational management competency (H1-1), the relationship formation competency (H1-2), the marketing competency (H1-3), and the entrepreneurship (H1-4), which are executive business management competency, have a positive effect on the organizational performance of the social enterprise respectively. Second, Hypothesis 2 indicates that the business management competency of social enterprise executives has a positive effect on organizational performance, social performance, and Hypothesis 2 has been adopted. In other words, the business management competency of the management on the social performance of the social enterprise is in the order of relationship forming competency (H2-2), marketing competency (H2-3), organizationalmanagement competency (H2-1), entrepreneurship (H2-4) Showed high influence. The higher the relationship formation competency, marketing competency, organizational competency, and entrepreneurship, which are the business management competency of the social enterprise management, the economic social performance of the social enterprise is more improved.

• International Journal of Aeronautical and Space Sciences
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• v.10 no.1
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• pp.30-36
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• 2009

Many formation guidance laws have been proposed for VAV formation flight. Since most autonomous formation flight methods require various active communication links between the vehicles to know motion information of other vehicles, damage to the receiver or the transmitter and communication delay are critical problem to achieve a given formation flight mission. Therefore, in this point of view, the method that does not need an inter-vehicle communication is preferred in the autonomous formation flight. In this paper, we first summarize the formation guidance law without an inter-vehicle communication using feedback linearization and sliding mode control proposed in previous study. We also propose the modified formation guidance law with robust disturbance observer, which can provide significantly better performance than previously mentioned guidance law in case that other vehicles maneuver with large accelerations. The robust disturbance observer can estimate uncertainties generated by acceleration of leader vehicle. By eliminating the uncertainties using the estimated uncertainties, VAVs are able to achieve the tight formation flight. The performance of the proposed approach is validated by numerical simulations.

• International Journal of Aeronautical and Space Sciences
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• v.12 no.1
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• pp.16-23
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• 2011

In this paper, nonlinear model predictive control (NMPC) is addressed to develop formation guidance for multiple unmanned aerial vehicles. An NMPC algorithm predicts the behavior of a system over a receding time horizon, and the NMPC generates the optimal control commands for the horizon. The first input command is, then, applied to the system and this procedure repeats at each time step. The input constraint and state constraint for formation flight and inter-collision avoidance are considered in the proposed NMPC framework. The performance of NMPC for formation guidance critically degrades when there exists a communication failure. In order to address this problem, the modified optimal guidance law using only line-of-sight, relative distance, and own motion information is presented. If this information can be measured or estimated, the proposed formation guidance is sustainable with the communication failure. The performance of this approach is validated by numerical simulations.

• Asia Pacific Journal of Business Review
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• v.3 no.2
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• pp.1-25
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• 2019

This study aims to examine the relationship between certain dimensions of Corporate Social Responsibility (CSR) with market performance, measured by Tobin's Q, on companies within various industries in Indonesia. This study disaggregates CSR into 7 dimensions: environment, energy, occupational safety and health, employee, product, community, and general. Samples consisted of 385 companies listed on the Indonesia Stock Exchange (IDX) during 2007-2014. OLS analysis shows that CSR contributes greatly to the formation of market performance of consumer goods, agriculture, and miscellaneous industries. The dimensions of CSR contribute differently to the formation of Q ratios in different industries. We also found that there are differences in the speed of effect of several dimensions of CSR on the formation of market performance; some CSR dimensions give immediate effect while others are lagged.

• Journal of ILASS-Korea
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• v.1 no.2
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• pp.50-56
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• 1996

In an fuel injection type gasoline engine, atomization of fuel droplet and mixture formation process are very important to understand engine combustion efficiency, and also has influence directly on the decision of engine performance and pollutant emission. In this study, perforated throttle valve instead of solid type throttle valve was developed and equipped to an SPI engine to promote secondary atomization and good droplet-air mixture formation. From the engine performance lest. it was verified that the case of perforated valve kas more advantages in each experimental parameters such as in cylinder gas pressure, mass burnt ratio, fuel consumption rate, and pollutant emission characteristics than that of solid one equipped. No matter what the same perforated valve, there are some distinct results in engine performance characteristics according to the perforate ratio.

• Journal of Navigation and Port Research
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• v.28 no.5
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• pp.373-384
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• 2004

The purpose of this research is to introduce the concept of "relationship formation factors" in inter-firm relations and to empirically demonstrate that they are effective in improving the relationship results by means of an mediating variable. Therefore, the basic model of this study consists of the independent, mediating, and dependent variables. First, the independent variables, that is, the relationship formation factors, are further classified into three components. transactional, relational, and environmental characteristics. Then, the study empirically examines how each of the three components influences the dependent variable. that is, the business performance(Load Factor), by way of the mediating variables, that is, trust and relationship commitment.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2004.04a
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• pp.321-332
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• 2004

The purpose of this research is to introduce the concept of "relationship formation factors" in inter-firm relations and to empirically demonstrate that they are effective in improving the relationship results by means of anmediating variable. Therefore, the basic model of this study consists of the independent, mediating, and dependent variables. First, the independent variable, that is, the relationship formation factors, is further classified into three components： transactional, relational, environmental characteristics. Then, the study empirically examines how each of the three components influences the dependent variable, that is, the business performance(Load Factor), by way of the mediating variables, that is, trust and relationship commitment.