• Journal of Korea Multimedia Society
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• v.14 no.3
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• pp.414-422
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• 2011

The paper is for top and bottom symmetrical phase controlled loop antenna using for multi-media devices. We developed a top and bottom phase control loop pattern arrangement methods for loop antenna in mobile devices like as a cell phone and PCS, WCDMA. In the loop antenna pattern, arrange close adhesive the loop antenna pattern $180^{\circ}$ cycle in wave length, the radiated electro-magnetic wave from close adhesive loop pattern in $180^{\circ}$ become to coherent wave than the phase controlled loop antenna has high efficiency and high radiation gain. To acquire a wide band width on phase controlled loop antenna, we arrange a top and bottom symmetrical architecture loop pattern that bas a $180^{\circ}$ wave length in each layer. Top and bottom each layer bas a U form pattern separated $90^{\circ}$ wave length each other. This architecture cause a well balanced electro-magnetic flow control that acquired wide bandwidth resonance response in loop pattern antenna. In experiment, we designed a WCDMA mobile multi-media antenna in $40mm{\times}6mm$ area thickness 0.2mm, in that passive experiment the radiation efficiency is over 50% and over 0dBi radiation average gain was acquired, in the active experiment in real multi-media device we acquired -4dBi average gain and 43% transmit/receive efficiency.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.4
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• pp.578-585
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• 2018

This paper proposes a design method for a 3-phase interior permanent magnet synchronous motor (IPMSM) and clamping force control method for an electro-mechanical brake (EMB) using co-simulation for a high-speed train (HST). A traditional pneumatic brake system needs much space for the compressor, brake reservoir, and air pipe. However, an EMB system uses up to 50% less space due to the use of a motor and electric wires for controlling the brake caliper. In addition, it can reduce the latency time for brake control because of the fast response and precise control. A train that has many brakes is advantageous for safety because of the control by sharing the braking force. In this paper, a driving method for a cam-shaft-type EMB is modeled. It is different from the ball-screw-type brakes that are widely used in automobiles. In addition, a co-simulation method is proposed using JMAG and Matlab/Simulink. The IPMSM was designed and analyzed with the JMAG tool, and the control system was simulated using Matlab/Simulink. The effectiveness of the co-simulation results of the mechanical clamping force and braking force was verified by comparison with the clamping force specifications of a HEMU-430X HST.

• Korean Security Journal
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• no.12
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• pp.309-333
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• 2006

These days, the majority of public service area presents increment of utilizing a contracting-out with the following reasons such as cost-efficiency, maintenance of population changes in flexible manner, and convenience of management. The social changes have influence on policing structure and regional security system as well as problems associated with accepting the contracting-out in the public policing sector. However, many issues such as limited contracting-out sector, difficulty of encouragement of participation to private sector, and limitation of making a contract with contracting-out would be brought up when initiate contracting-out to the public policing sector. Changing security system to lower budget, planning restructure of organization, developing alterable partial contracting-out, establishing private and public cooperate system and rationalizing contract system are the suggestions to solve and modify the raising problems. This study suggests a differentiate regulation of policing services compare to currently existing contracting-out method to consider a distinctive working environment. The suggestions are as follows: 1. develop a security segregate model, 2. build a cooperative system between private and public policing sector, 3. broaden opportunity of participation of private policing sector, 4. open-competition among qualified private tender to make a contract. The private contracting-out in the public security service sector should be manage in different manner compare to other private contracting-out in government-oriented public service sector. Since work performance of each private contracting-out agency is strongly bond to safety of every civilian in the nation, it is essential to increase its standard of qualification of each agency.

• Korea journal of population studies
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• v.19 no.1
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• pp.73-92
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• 1996

There are basically three approaches of surveys on the economically active population, namely Labor Force Approach (or Current Status Approach), Usual Status Approach, and Gainful Worker Approach. The selection of an approach among these approaches to be applied to a survey or population census should take into considerations the purpose and background of the survey or the census and the socio-economic situation of a country. In the Korean Population and Housing Census series which have been taken almost every five years since its first round in 1925, a sample survey on the economically active population has been adopted since the 1960 round of census. Even if the labor force approach continued to be applied to the censns prior to 1980, the approach has been different from one round to another in recent rounds. It may be suggested that the labor force approach continue to be adopted for the Korean Population and Housing Census for the following reasons: 1) the proportion of seasonal workers to the total workers is very small, 2) the proportion of population whose type of activity for a specific duration is different from that for one year is small, 3) the approach for the census should be the same as that for a variety of sample surveys on the economically active population which adopt the labor force approach, since the census functions as a population as well as a bench mark for those sample surveys, 4) an application of labor force approach will facilitate international comparisons since most of countries that conduct a population census adopt this approach, 5) the labor force approach can improve the reliability of results, thanks to its short reference period, etc.

• Korean Journal of Construction Engineering and Management
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• v.7 no.2 s.30
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• pp.71-80
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• 2006

It is required to study systematical on the concrete quality management to extend structure life because rebuilding effect is reducing under present condition of large sized and high stories structure. Concrete, which shows its intensity by hydrating action and a big change in quality according to hot weather and temperature, produces a lot of quality problem under hot and cold weather. Because of each specification and construction plan which does not have basic standard on site, concrete's quality is irregular and makes some defect. As a result, Dae-gu is fumed out to be the longest area after investigating application period and days focused on 8 cities weather information about t relationship between hot weather circumstance and construction environment. Therefore, we first surveyed the curing construction processing in the region and found out the problem of quality management. Then figure out the way of solution. Moreover, we integrated curing quality management, which is applied differently to each site, to have equal quality and to reduce defect from construction site. And then, based on various test of construction condition and analysis of quality management item, we suggest effective concrete quality management to make curing construction standard guide and plan under hot weather.

• The Transactions of the Korea Information Processing Society
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• v.7 no.8
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• pp.2349-2360
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• 2000

In medical image processing, if new technologies arc developed, they arc applied to real clinical cases. The results are to be analyzed by doctors to improve the new technologies. So, it is important for doctors to have a tool that helps the doctors in applying the new technologies to clinical cases and analyzing the clinical results. In this paper, we design and implement a visual programming environment where non-programming experts, such as medical doctors, can easily compose a medical image processing application program. A set of image processing functions are implemented and represented as icons. Thc user selects functions by clicking correslxmding icons. The users can easily find necessary' functions from the visualized library. A user selects a function from the visualized library and [Jut the function node into a canvas of Visual Programming Interface. The user connects nodes to compose a dataflow diagram. The connected dataflow diagram shows the now of the program. Hyperbolic Tree is helpful in visualizing a set of function icons in a single screen because it provides both the whole stmcture of the function Iihrary and the details of the focused functions at the same time. We also developed a CUI builder where the user interfaces of the medical image processing applications are composed. Therefore. non'programming experts such as physicians can apply new medical image processing algorithms to clinical cases without performing complex computer programming procedures.

• Industry Promotion Research
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• v.5 no.1
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• pp.47-52
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• 2020

In this study, parallel work-learning training, which was started in 2013 as a pre-employment promotion policy, is an important factor that determines the success or failure of training. As a time when various institutional supplementation is needed to encourage company participation, this study is to identify the factors of participation of companies participating in work-learning parallel. To this end, a questionnaire survey was conducted of companies participating in parallel work-learning in Chungnam, and the results were analyzed using the structural equation model. As a result of the study, the reason for the company's participation in parallel work-learning was firstly, 84% of government subsidy received education and training expenses. Second, 66% of workers were able to pay less than regular workers, and thirdly, it was easy to hire new employees in the field. 26%, 17% of them were invited by acquaintances for no particular reason. Therefore, the study suggests that participation in the work-learning parallel training contributes to the management costs, management of employee turnover, and human resource development. In future research, it is necessary to subdivide tests and estimates by conducting studies on regions, occupations, gender, wages, and years of service in Korea.

• Journal of Broadcast Engineering
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• v.13 no.6
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• pp.817-827
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• 2008

The terrestrial-digital multimedia broadcasting(T-DMB) is now provided for the public service and the number of receivers reaches 15 million at the present of August 2008. The service of T-DMB itself has been succeeded in the presence. It is however remained as a supplementary role of stationed TV. It is necessary to find an additional business model as a new media to acquire surplus escaping from the deficit of the present T-DMB service. In the present paper, data service of T-DMB is proposed as candidate of such solution. Especially, TTI(Traffic and Travel Information) service is proposed as a killer application using TPEG(Transport Protocol Experts Group). At present, TPEG has not been so popular in the sense of various user satisfaction. Thus the variety of service including bi-directional service using DMB2.0 as in the sphere of Web2.0 is necessary for the service providers. In the paper, the restriction of TPEG-POI(Point of Interest) application service using the conventional mobile communication infrastructure is indicated. To overcome such restriction, TPEG-UCM(User Created Message) application service model using individual bi-directional media which is initiated and interacting by the users is proposed. In the experiment, the application program shows the usability of the proposed method so that the implementation results show its operability.

• Applied Chemistry for Engineering
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• v.24 no.5
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• pp.456-470
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• 2013

Hollow-fiber membranes, is one of the new technologies that is growing rapidly in the past few decades. In addition, separation membranes using polymer materials, have attracted attentions in various fields including gas separation, fuel cells, water treatment, wastewater treatment, and organic separation. Nanofiltration (NF) membranes having the separation characteristics in the intermediate range between ultrafiltration and reverse osmosis (RO) membranes for liquid separation, with relatively low investment cost and operating pressure lower than that of RO membranes, have high permeance and rejection performance of multivalent ions as well as organic compounds of molecular weight between $200{\sim}1000gmol^{-1}$. In this paper, we would like to review the research trends on the various structure control and characterization of NF hollow fiber membranes with respect to materials and the methods of preparation (phase inversion method and interfacial polymerization method). Currently, most of NF membranes have been manufactured by plate and frame types or spiral wound types. But hollow fiber types have delayed in commercial products, because of the weak strength when to produce on the basis of the existing materials, therefore the development of new materials or improvement of existing materials will be needed. If improving manufacturing technology is available, hollow fiber types will replace spiral wound types and gradually show a higher market share.

• Applied Microscopy
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• v.38 no.3
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• pp.235-243
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• 2008

A compact soft x-ray microscope operated in the 'water window' wavelength region ($2.3{\sim}4.4nm$) was used for observing cells with nano-scale spatial resolution. To obtain cellular imaging captured with colloidal gold nanoparticles using a compact soft x-ray microscope. The colloidal gold nanoparticles showed higher contrast and lower transmission more than 7 times than that of cellular protein on the soft x-ray wavelength region. The structure and thickness of the cell membrane of the Coscinodiscus oculoides (diatome) and red blood cells were seen clearly. The gold nanoparticles within the HT1080 and MDA-MB 231 cells were seen clearly on the soft x-ray microscopy. The gold nanoparticles were aggregated within vesicles by endocytosis.