• 한국산업경영시스템학회:학술대회논문집
• /
• 한국산업경영시스템학회 2002년도 춘계학술대회
• /
• pp.445-454
• /
• 2002

This article explains the theory of multiple mode/physical coordinate synthesis method in order to analyze the dynamic characteristics for an huge marine engine. The theory leads to make a simulation code. The natural frequencies obtained from the simulation code is compared to those from a commercial analysis software, ANSYS. The simulation code is well reviewed.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
• /
• pp.1376-1379
• /
• 1996

In this paper a GPS receiver is developed using commercial chipsets. GP2010 RF front end and GP2021 Multi-channel correlator of GEC PLESSY are adapted in designing the receiver hardware. MC 68340 is used for controlling the correlator GP2021 and implementing the navigation processing. Also presented are some test results of the developed receiver whose software has an interrupt driven structure rather than common real-time kernel based structure.

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2001년도 춘계학술대회논문집B
• /
• pp.651-657
• /
• 2001

This article explains the theory of multiple mode/physical coordinate synthesis method in order to analyze the dynamic characteristics for an huge marine engine. The theory leads to make a simulation code. The natural frequencies obtained from the simulation code is compared to those from a commercial analysis software, ANSYS. The simulation code is well reviewed.

• 한국연소학회:학술대회논문집
• /
• 한국연소학회 2013년도 제46회 KOSCO SYMPOSIUM 초록집
• /
• pp.91-94
• /
• 2013

Commercial computational fluid dynamics (CFD) codes traditionally rely on the computational efficiency of the simplified single-film apparent char kinetic model to predict char particle temperatures and char conversion rates in pulverized coal boilers. The aim of this study is to evaluate the reliability of the single-film apparent kinetic model and to suggest the importance of proper use of this model. For this, a parametric study was conducted with a consideration of main parameters such as Stefan flow, product species, particle evolution, and kinetic parameters.

• 항공우주정책ㆍ법학회지
• /
• 제23권2호
• /
• pp.3-29
• /
• 2008

항공운송과 관련하여 우리나라는 1955년 헤이그 의정서에 의하여 개정된 바르샤바협약과 1999년 몬트리올 협약에 가입하여 국제운송에 관하여는 적용할 법률을 가지고 있지만, 현재 국내항공운송에 관하여는 적용될 법률이 없는 실정이다. 법무부는 상법 내에 항공운송편을 제정하기로 결정하고, 항공운송편제정 특별위원회를 구성하였다. 동 위원회는 2008년 여름 항공운송편 초안을 완성하여 동 초안은 현재 법제처의 심의를 받고 있다. 항공운송편을 제정함에 있어서는 현재까지 성립된 항공운송관련 대부분의 조약을 수용하였다. 항공운송법의 편제는 1장 통칙, 제2장 운송, 제3장 지상 제3자의 손해에 대한 책임 등 총 3개의 장을 두었다. 우리나라가 항공운송에 관한 단행법을 제정하지 않고 상법 제6편에 항공운송편을 두어 제2편 상행위편에 육상운송을 규정하곤 제5편에 해상운송에 관한 규정을 둔 것과 함께! 통합적인 운송법체계를 가진 것은 입법례가 없는 매우 독특한 입법형식을 취한 것이다. 특히 항공기운항자의 지상 제3자의 손해에 대한 책임에 관한 로마조약체계까지도 수용하여 함께 규정한 것은 국내항공운송법체계를 완성한 것으로서 매우 의미 있는 일이라고 생각한다.

• 신재생에너지
• /
• 제7권4호
• /
• pp.50-57
• /
• 2011

A wind turbine simulation program for the coupled dynamics of aerodynamics, elasticity, multi-body dynamics and controls of turbine is newly developed by combining an aero-elastic code and a multi-body dynamics code. The aero-elastic code, based on the blade momentum theory and generalized dynamic wake theory, is developed by NREL(National Renewable Energy Laboratory, USA). The multi-body dynamics code is commercial one which is capable of accounting for geometric nonlinearity and twist deflection. A turbulent wind load case is simulated for the NREL 5-MW baseline wind turbine model by the developed program and FAST. As a result, the two results agree well enough to verify the reliability of the developed program.

• 한국전산유체공학회:학술대회논문집
• /
• 한국전산유체공학회 2010년 춘계학술대회논문집
• /
• pp.508-516
• /
• 2010

An efficient code has been developed to predict dispersion of indoor air pollutants The computing capability of the code has been compared with that of a commercial code inn a benchmark test. After that, the code has been employed to compute dispersion of a pollutant released from a new furniture, a kind of Sick Building Syndrome (SBS). A sofa which generates formaldehyde is implemented by using an immersed boundary method. Large Eddy Simulation (LES) is employed to obtain time-dependent velocity and scalar fields. LES has bee regarded as an academic tool, but the newly-developed code reveals a possibility of application of LES to practical problems, especially dispersion of indoor pollutants.

• 설비공학논문집
• /
• 제22권11호
• /
• pp.735-744
• /
• 2010

An efficient code has been developed to predict dispersion of indoor air pollutants. The computing capability of the code has been compared with that of a commercial code in a benchmark test. After that, the code has been employed to compute dispersion of a pollutant released from a new furniture, a kind of Sick Building Syndrome(SBS). A sofa which generates formaldehyde is implemented by using an immersed boundary method. Large Eddy Simulation (LES) is employed to obtain time-dependent velocity and concentration fields. LES has been regarded as an academic tool, but the newly-developed code reveals a possibility of application of LES to practical problems, especially dispersion of indoor pollutants.

• 한국해양공학회지
• /
• 제27권1호
• /
• pp.1-8
• /
• 2013

This paper presents the results of experimental and numerical research on the slamming phenomenon. Two experimental techniques were proposed in this study. The traditional free drop tests were carried out. However, the free drop tests done in this study using an LM guide showed excellent repeatability, unlike those of other researchers. The coefficients of variation for the drop test done in this experiment were less than 0.1. The other experimental technique proposed in this study was a novel concept that used a pneumatic cylinder. The pneumatic cylinder could accelerate the specimen over a very short distance from the free surface. As a result, high rates of repeatability were achieved. In the numerical study, the development of in-house code and utilization of commercial code were carried out. The in-house code developed was based on the boundary element method. It is a potential code. This was mostly applied to the computation of the wedge entry problem. The commercial code utilized was FLUENT. Most of the previous slamming research was done under the assumption of a constant body velocity all through the impact process, which is not realistic at all. However, the interaction of a fluid and body were taken into account by employing a user-defined function in this study. The experimental and numerical results were compared. The in-house code based on BEM showed better agreement than that of the FLUENT computation when it cames to the wedge computation. However, the FLUENT proved that it could deal with a very complex geometry while BEM could not. The proposed experimental and numerical procedures were shown to be very promising tools for dealing with slamming problems.

• 대한지역사회영양학회지
• /
• 제2권4호
• /
• pp.624-632
• /
• 1997

This study was conducted to evaluated the nutrition quality of the commercial supplementary foods for infants and young children and to seek a solution to the establishment of standards of nutrient requirements for supplementary foods in Korea. Information on food ingredients, nutrient contents, claims about usefulness of food components and instructions for feeding preparation were obtained from the labels of 33 commercial supplementary foods manufactured by 4 different domestic companies. According to the standard of supplementary foods for infants and young children described in the Korean Food Code, the commercial supplementary foods were categorized into two different types, weaning food and baby food. All the commercial weaning foods were in powder form and mainly composed of cereals, whereas all the baby foods were mainly composed of fruits in the form of canned juice. The weaning foods contained more nutrients than the baby foods did, and the nutrient levels of the weaning foods expressed as nutrient density on energy basis were higher than the RDA for infants aged 5 to 11 months, suggesting that the commercial weaning foods provide adequate amounts of nutrients. If one followed the instructions for feeding preparation appearing on the label, however, recommended amounts of intake of the weaning foods would provide too much energy as well as nutrients. There were many differences in nutrient standards of weaning foods between the Korean Food Code and Codex international food standard. In conclusion, the establishment of standards for nutrient requirements for the supplementary foods requires significant scientific studies on what nutrients are the most inadequate in Korean infants and young children feeds and what levels of nutrients should be added to the foods in order to supplement their nutrition. In addition, it is very important to have a strong scientific basis to support our standard when discrepancies exist between our standard and the international standard. (Korean J Community Nutrition 2(4) : 624-632, 1997)