• Journal of the Korean Society for Aviation and Aeronautics
• /
• v.27 no.2
• /
• pp.26-36
• /
• 2019

Although the investment size of R&D in Aviation and Aerospace Industries is increasing, R&D performance has not been quite good considering resources invested in it. This study is to find which R&D critical factors affect R&D Performance in aviation and aerospace industries. According to the result of research, a technology provider factor, an organization factor, a system factor and a market environment factor influence positively on financial performance, and a policy factor influences negatively on financial performance. Otherwise, a technology provider factor and an organization factor influence positively on non financial performance, and technology factor influences negatively on non financial performance. Thus, personnel involved in R&D of Aviation and Aerospace Industries should develop policy and system taking positive and negative factors to improve R&D performance. It could lead to take the better performance from R&D in Aviation and Aerospace Industires.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2004.03a
• /
• pp.472-478
• /
• 2004

This paper describes the characteristics of the unsteady pressure on the stator surface induced by rotor viscous wakes. The primary object of this study is to investigate the effects of axial spacing between the rotor and the stator and three-dimensional vane geometries such as stator sweep and stator lean on the unsteady pressure fluctuations on the stator vane. To predict these fluctuations, unsteady three-dimensional Navier-Stokes analyses are performed. Furthermore, a three-dimensional analytical method using unsteady lifting-surface theory is also used to elucidate the mechanism of interaction of passing rotor wakes with downstream stator. Five different fan configurations with three sets of stator geometries, which are three radial stator configurations with different axial spacing, the swept stator and the swept and leaned stator, are used for this study. It is found that, in axial spacing between rotor and stator, the effect of radial phase skew of incoming rotor wake is important for the reduction of the induced unsteady pressure in addition to the rotor wake decay. It is also shown that incorporation of stator sweep and lean is effective to reduce this unsteady pressure.

• Journal of the Korean Society of Systems Engineering
• /
• v.6 no.2
• /
• pp.7-14
• /
• 2010

Systematic and efficient Management of Development requirements will lead to success of project such as aircraft system development consisting of complex subsystem. For such reason, Requirements management tools have been used in most of project. In the case of FA-50 development project, requirements management tools have been used for systematic and efficient management of FA-50 Requirements. Especially FA-50 system was designed on the basis of the TA-50 configuration. Therefore, it needs traceability of requirements about functions, which have been already developed and will be newly developed. This paper was described about the implementation method of FA-50 development requirements traceability management.

• Asian-Australasian Journal of Animal Sciences
• /
• v.3 no.4
• /
• pp.337-341
• /
• 1990

An investigation was conducted to determine whether the rumen modifiers lasalocid and avoparcin, when included in molasses/urea based supplements, enhanced liveweight performance, in early weaned calves. As part of the study the broad-spectrum parasiticle Avermectin B1 was given to the calves to assess any undesirable side effects on animals of less than four months of age. There were no significant (p>0.05) liveweight responses to supplementation when the rumen modifiers lasalocid and avoparcin were included in supplement rations. Lasalocid reduced supplement intake, however, it had no adverse effect on liveweight gain. Avoparcin substantially improved growth when cottonseed meal was included in the ration. Weaners treated with Avermectin B1 tended to show a greater liveweight gain than untreated weaners during the experiment (p<0.10) and no adverse side effects were noted.

• 한국디지털정책학회:학술대회논문집
• /
• 2005.06a
• /
• pp.349-385
• /
• 2005

The purpose of this paper is to analyze the activation methods of GIS industries through GIS industry current issue analysis in Korea to provide as following. First of an in order to analyse current GIS industries, there are three divisions as follows: existing GIS industry, new technology GIS industry, and commercial GIS industry. The existing GIS industry includes survey industry, municipality UIS and remote sensing. The new technology GIS industry has telematics industry, LiDAR industry, ubiquitous industry, LBS industry, internet, and u-city industry. The commercial GIS industry consists of civilian request GIS industry and spacial data distribution industry. The national geographic information industry contains problems and directions of the 1st, 2nd NGIS and 3rd NGIS plan direction policy. These classified GIS industries present various problems of policies and invaluable results for the future GIS industry activation directions as follows: Presence of the GIS contents technologies win be the most important core for the GIS industry activation related to IT839 policy of the government in Korea.

• Proceedings of the KIEE Conference
• /
• 1991.11a
• /
• pp.341-344
• /
• 1991

Current controlled pulse width modulation(PWM) for voltage source inverter(VSI) is one of the control method which controls the current directly so that we can perform vector control because it reduces the orders of differential equations of the induction machine. This paper propose a Fuzzy current controlled PWM which properly minimize a current ripple using Fuzzy theory in a constant switching frequency. This technique is applied to an electrical drive system with an induction machine(IM) by simulation. By comparison with the known classical method such as ramp comparison, hysteresis band method, our contribution shows the better performances.

• Journal of Korean Society for Quality Management
• /
• v.29 no.2
• /
• pp.93-103
• /
• 2001

This study examined the social perceptions on the women work force in Korean service industries. 100 questionnaires per each of five service industries, hotel, PCS, department store, general hospital and bank (500 altogether) were distributed to general consumers to measure perceived service quality and perceptions on the women employees in the those service industries. It was found that consumers were not very satisfied with the service quality of the industries. They felt the necessity of women workforce in service industry and agreed to that women employees posessed management quality and had potential to develop.

• Journal of Korean Society for Quality Management
• /
• v.27 no.4
• /
• pp.1-19
• /
• 1999

This study examines the service quality management and the use of women employees for the productivity improvement in Korean service industry. Five service industries, bank, hotel, PCS(Personal Communication Service), department store, and hospital industry were chosen for this study. The results indicate that the five industries show different characteristics. It was found that department stores made the most effort to improve service quality among the five industries and that hospitals did the least effort. In the use of women employees, the proportion of women in service industry is much higher than that in the manufacturing industry, but the proportion of women in management level is still very low. Women employees do not feel high degree of sexual discrimination. But they feel unfairness in promotion and payment, and low degree of job satisfaction.

• Proceedings of the KIEE Conference
• /
• 2009.07a
• /
• pp.1473_1474
• /
• 2009

To develop electrically reliable high voltage apparatuses, the experimental study on the electrical breakdown field strength is needed, as well as theoretical approach. In this paper, lightning impulse breakdown characteristics considering utilization factors are investigated for the establishment of insulation design criteria of an high voltage apparatus. The utilization factors are represented as the ratio of mean electric field to maximum electric field. Dielectric experiments are performed by using five kinds of sphere-plane electrode systems made of stainless steel. As a result, it is found that dielectric characteristics are affected by not only gap length but also utilization factor of electrode systems. The results are expected to be applicable to the design of high voltage apparatuses.

• Proceedings of the KIEE Conference
• /
• 2005.07a
• /
• pp.489-491
• /
• 2005

This paper presents the application study of substation automation protocol, IEC 61850 to digital relay (HiMAP). Especially, it implements the data modeling, ACSI definition, GOOSE, MSVCB and data service required in the existing digital relay. To verify the system performance, we develop the process emulator and HiMAP emulator, and describe the results.