• 한국유체기계학회 논문집
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• 제18권4호
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• pp.22-29
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• 2015

In this study, an in-house program to predict steady state operation of micro gas turbines is constructed using MATLAB. The program consists of two parts: design and off-design simulations. The program is fully modular in its structure, and performance of each component (compressor, combustor, turbine, recuperative heat exchanger and pipe elements) is calculated in a separate calculation module using mass and energy balances as well as models for off-design characteristics. The off-design modules of compressor and turbine use performance maps, which are program inputs. The off-design operation of a micro gas turbine under development was predicted by the program. The prediction results were compared with those by commercial software, and the validity of the in-house program was confirmed.

• 대한임베디드공학회논문지
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• 제18권5호
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• pp.209-215
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• 2023

This study proposes an AC servo motor control program structure and its implementation method to efficiently integrate 13 types of additional compensation algorithms into the basic FOC (field-oriented control) algorithm program. Various compensation algorithms are necessary to enhance the stability and performance of machine tools by compensating for interference from disturbances and vibrations. Each compensation algorithm is implemented as a separate, independent function and called from a switch-case statement in the ISR (interrupt service routine) of the PWM (pulse-width modulation) device. The advantages of this approach include facilitating not only debugging and testing but also reducing the possibility of errors during the program development phase. Thus, it is easy to add and activate each specific compensation algorithm for the program update during the program operation phase. The implemented motor control program was experimented with a single-axis feed shaft testbed driven by a commercial AC servo motor control drive board and a 750 Watts SPMSM (surface-mounted permanent magnet synchronous motor), and the results verified its normal operation and performance improvement.

• 유통과학연구
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• 제17권6호
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• pp.43-56
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• 2019

Purpose - With the increasing number of small business owners who reports the cessation of their businesses, the rate of closing the business within the year is increasing as well. The efforts have been made continuously to revitalize the business through the inflow of government or private capital. Maintaining the fast-changing commercial districts with the existing support is difficult, so it is urgent state that needs for commercial district reorganization. The differentiate aspect is that this new measures for small-block-unit commercial modeling can be introduced to promote these aging/deposit private-owned shops politically. Research design, data, and methodology - This study is to develop a sustainable theme shopping rehabilitation method which considers the characteristics of local cities based on the case studies of developed countries' commercial areas to revitalize the central urban areas of local cities. Results - The purpose of this study as stated above is to manage the local commercial area through the program that purchases the empty stores, and the measure to secure the autonomy among stores. Conclusions - The government should concentrate on projects such as vacant store purchase programs, which are omitted from past achievements, and maximize the effect of the project through inter-departmental project packages.

• 대한간호학회지
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• 제34권8호
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• pp.1477-1482
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• 2004

Purpose. With the continuous spread of the AIDS virus and other sexually transmitted diseases (STDs) throughout Asia, it has become imperative for HIV/AIDS prevention outreach programs to stress the need for using prophylactics as one form of protection. This is particularly true for commercial sex workers. This pilot study was conducted to investigate the rate of condom use among the commercial sex workers in Korea and reasons why they frequently do not wear condoms during sexual intercourse. Methods. Fifty female commercial sex workers who worked in the Yong San area were recruited while outreach was performed and forty eight responses were analyzed due to two incomplete questionnaires. The data were collected on June 28, 2004 as part of an outreach program for condom use promotion. Results. The subjects ranged in age from 21 to 45 years. Nearly half of the subjects ($47.9\%$) did not consistently use condoms. The major reason for not using protection was clients' reluctances for using condoms. When condoms were used, the subjects preferred lubricant-rich and less painful condom during intercourse. Conclusion. Due to the inconsistent use of condoms, it is clear that many commercial sex workers and clients are susceptible to sexually transmitted diseases. Therefore, it is important to not only educate commercial sex workers, but also to educate their pimps and clientele about the importance of condom use. In general, it is recommended that practical strategies and a policy for condom use promotion be developed.

• 대한인간공학회지
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• 제33권6호
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• pp.515-532
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• 2014

Objective: The purpose of this study is to define consumers' affection on the interior design of commercial cars in terms of its design factors: color, embossing and gloss as independent factors. Background: Existing affective studies related to interior of vehicle focus on just sedans. However, there is no affective study about the interior of commercial cars. In addition, it is hard to change levels to which manufactures want. Method: Representative design factors were drawn using ANOVA and SNK analysis and definitive affective vocabularies were drawn using factor analysis. Furthermore, the results of 3D experiment were analyzed using ANOVA and LSD analysis. 3D images for the experiment were made using 3D max program. The experiment revealed that consumers discerned the differences in levels of each design factor and affective vocabulary. Results: The ANOVA revealed that beige color "A" type and non-gloss were the most preferred design in terms of the affective vocabularies and total preference. Conclusion: The result of the experiment may help manufactures to design the interior of commercial cars in the near future. Furthermore, the ANOVA result of affective vocabularies evaluation is expected to suggest a meaningful guideline. Application: The study results may be utilized as a guideline for interior design of commercial cars.

• Journal of Advanced Marine Engineering and Technology
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• 제35권5호
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• pp.608-615
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• 2011

The objective of this study is to investigate the flow characteristics of polluted air behavior in rectangular tunnels using a PIV system and a commercial CFD program. The PIV experiments are simulated by using the olive oil as the tracer particles in scaled rectangular tunnels. Each model has one of four different outlet vents, each dimensionless L/H ratio of which is 0, 0.375, 0.75 and 1.125, respectively as the locations of each outlet are away from the vertical centerline through the inlet. A commercial CFD program, ANSYS CFX, was used to examine the velocity fields and the pressure distributions in numerical simulations. The kinematic viscosity of the air flow of $1.51{\times}10^{-5}m^2/s$ and the flow velocity of 0.3 m/s at the inlet are given under the same conditions in order to analyze the polluted air flow characteristics experimentally and computationally. This study is considered to examine the effect of the outlet locations in the naturally ventilated tunnel models.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2007년도 춘계학술대회논문집
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• pp.1008-1016
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• 2007

The purpose of this paper is to investigate the Natural Frequency behavior characteristic of Wind Turbine Tower model, and calculated the stress values of thrust load, wave load, wind load, current load, and gravity load. The offshore Jacket Type Tower which was installed in Vitenam South China Sea is used for the study. Natural frequency and mode shape are calculated with commercial program using the measured vibration. The finite element analysis is performed with commercial F.E.M program(ANSYS) on the basis of the natural frequency and mode shape.

• International Journal of Industrial Entomology and Biomaterials
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• 제25권2호
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• pp.147-151
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• 2012

Fifteen races resulted from silkworm breeding program at Sericulture Research Department (SRD) were used for hybridization. Fourteen hybrids were obtained and coded as; Giza C, D, R, S, T, U, A, V, W, P, H, L and Qanater 1, 2. The traits of cocoon weight, cocoon shell weight, pupal weight, cocoon shell ratio, silk productivity, fifth instar duration, total larval duration, number of cocoon per liter and pupation ratio were evaluated. Data were analyzed by using three formulae of heterosis over better, mid and check parent values. Hybrids of Giza V, C, N, Qanater 1 and 2 are promising and could be used in commercial cocoon production. Generally, there are some new hybrids can be exploited in commercial scale. Also, the local races can be evolved using the hybridization, inbreeding and selection program.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2010년도 춘계학술대회 논문집
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• pp.942-946
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• 2010

As the major sources of interior noise of train at running condition are the wheel/rail contact noise, the traction motor's noise and the driving gear's noise and these noise sources are transmitted through the car body, the noises of HVAC and air duct can be ignored. But the interior noise of train at standstill condition is decided by HVAC's noise and noise from the diffuser through the air duct. the interior noise prediction of train at standstill condition should be performed considering the shape of air duct, the air velocity and noise reduction property inside the air duct. But it is hard to estimate the interior noise level by the numerical method. Therefore train maker predict the interior noise level using The commercial noise prediction program. This paper introduce the noise prediction method of the train at standstill condition using the commercial program appling the ray tracing method and statistical energy analysis.

• 대한기계학회논문집B
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• 제25권4호
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• pp.451-460
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• 2001

An analysis program for the thermal performance prediction of steam turbine cogeneration systems with multi-extraction, reheat and regeneration has been developed on the basis of the thermodynamic heat balance method. Heat balance analyses were performed for a commercial cogeneration power plant using the program. Its appropriateness was verified by comparing its heat balance results with those of other commercial programs and those provided by the original system designer. Further parametric analyses were carried out and performance improvement measures in designing the plant were suggested.