• Proceedings of the KSRS Conference
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• 2002.10a
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• pp.229-234
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• 2002

Under the hostile influence of the extreme space environmental conditions due to the deep space and direct solar flux, the thermal control in space applications is especially of major importance. There are tight temperature range restrictions for electro-optical elements while on the other hand there are low power consumption requirements due to the limited energy sources on the spacecraft. So, we usually have strong requirement of thermal and power control module in space applications. In this paper, the design concept of a thermal and power control module in the MSC(Multi-Spectral Camera) system which will be a payload on KOMPSATII is described in terms of H/W & S/W. This thermal and power control module, called THTM(Thermal and Telemetry Module) in MSC, resides inside the PMU(Payload Management Unit) which is responsible for the proper management of the MSC payload for controlling and monitoring the temperature insides the EOS(Electro-Optic System) and gathering all the analog telemetry from all the MSC sub-units, etc. Particularly, the designed heater controller has the special mode of "duty cycle" in addition to normal closed loop control mode as usual. THTM controls heaters in open loop according to on/off set time designed through analysis in duty cycle mode in case of all thermistor failure whereas it controls heaters by comparing the thermistor value to temperature based on closed loop in normal mode. And a designed THTM provides a checking and protection method against the failure in thermal control command using the test pulse in command itself.

• Journal of computational fluids engineering
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• v.21 no.2
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• pp.112-119
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• 2016

NEXTSat-1 is the next-generation small-size artificial satellite system planed by the Satellite Technology Research Center(SatTReC) in Korea Advanced Institute of Science and Technology(KAIST). For the control of attitude and transition of the orbit, the system has adopted a RHM(Resisto-jet Head Module), which has a very simple geometry with a reasonable efficiency. An axisymmetric model is devised with two coil-resistance heaters using xenon(Xe) gas, and the minimum required specific impulse is 60 seconds under the thrust more than 30 milli-Newton. To design the module, seven basic parameters should be decided: the nozzle shape, the power distribution of heater, the pressure drop of filter, the diameter of nozzle throat, the slant length and the angle of nozzle, and the size of reservoir, etc. After quasi one-dimensional analysis, a theoretical value of specific impulse is calculated, and the optima of parameters are found out from the baseline with a series of multi-physical numerical simulations based on the compressible Navier-Stokes equations for gas and the heat conduction energy equation for solid. A commercial code, COMSOL Multiphysics is used for the computation with a FEM (finite element method) based numerical scheme. The final values of design parameters indicate 5.8% better performance than those of baseline design after the verification with all the tuned parameters. The present method should be effective to reduce the time cost of trial and error in the development of RHM, the thruster of NEXTSat-1.

• Journal of Korea Multimedia Society
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• v.5 no.3
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• pp.290-297
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• 2002

The appearance of web technology has accelerated the role of the application of multimedia technology, computer communication technology and multimedia application contents. Recently WBI model which is based on web has been proposed in the part of the new activity model of teaching-teaming. How to learn and evaluate is required to consider individual learner's learning level. And it is recognized that the needs of the efficient and automated education agents in the web-based instruction is increased But many education systems that had been studied recently did not service fluently the courses which learners had been wanting and could not provide the way for the learners to study the learning weakness which is observed in the continuous feedback of the course. In this paper we propose design of multi-module system for course scheduling of learner-oriented using weakness analysis algorithm. First proposed system monitors learner's behaviors constantly, evaluates them, and calculates his accomplishment and weakness. From this weakness the multi-agent prepares the learner a suitable course environment to strengthen his weakness. Then the learner achieves an active and complete teaming from the repeated and suitable course.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.6
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• pp.2739-2745
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• 2014

Background: Health-related quality of life (HRQL) is a fundamental outcome in oncology patients and quality of life (QOL) assessment requires clinically relevant questionnaires. The purpose of this study was translation and definition of measurement properties and the clinical validity of Quality of Life Questionnaire (QLQ)-OG25 module in Persian patients with oesophagus, oesophagogastric junction (OGJ) or gastric cancers. Materials and Methods: The translation procedure followed European Organization for Research and Treatment of Cancer (EORTC) guidelines. Both EORTC QLQ-OG25 and a core questionnaire (EORTC QLQ-C30) were administered to patients with oesophagus (150), OG junction (93) and gastric (32) cancer undergoing multi-modal treatments. Convergent and discriminant validity, Cronbach's alpha coefficient and known-groups comparisons were used to examine reliability and validity. Results: In all, 275 patients (mean age 62 years) completed both questionnaires. Compliance rate was high and the questionnaire module was well accepted. We found good reliability for multi-item subscales of QLQ-OG25 (Cronbach's alpha coefficients 0.76-0.89). About 73% had TNM staging and scales distinguished between clinically distinct groups of patients. However, patients in palliative group experienced compromised functional status and worse treatment-associated symptoms than those in the potentially curative group. Test-retest scores were consistent. Multi-trait scaling analysis demonstrated good convergent and discriminant validity. Conclusions: Overall, the Persian version of QLQ-OG25 demonstrated psychometric and clinical validity that supports its application as a supplement to the original tool (EORTC QLQ-C30) when assessing HRQL in patients with upper-gastrointestinal (GI) cancer both in curative and palliative phases.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.12 no.12
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• pp.2140-2145
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• 2008

We design and synthesize a 128-point FFT processor for multi-band OFDM, which can be applied to a UWB transceiver. The structure of a 128-point FFT processor is based on a Radix-2 FFT algorithm and a R2SDF pipeline architecture. The algorithm is efficiently modeled in VHDL and the result is simulated using Modelsim. Finally, they are synthesized on Xilinx Vertex-II FPGA, and an operational frequency of 18.7MHz has been obtained. It is expected that the proposed 128-point FFT processor can be applied to an entire FFT block as one of parallel processed FFTs. In order to obtain the enhanced maximum frequency of operation, we design the FFT module consisting of four 128-point FFT processors for parallel process. As a result, we achieve the performance requirement of computing the FFT module in multi-band OFDM symbol timing in 90nm ASIC process.

• Journal of the Semiconductor & Display Technology
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• v.20 no.1
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• pp.77-82
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• 2021

Using a multi-array needle module developed for coating of high-density cylindrical microlens array (C-MLA), we have fabricated an anti-Moiré filter for LED screens. The Moiré phenomenon appears due to the interference between the array pattern of image sensors in a camera and the non-emission area (grid pattern) of a LED screen. To suppress it, we have employed poly(methyl methacrylate) (PMMA) and coated it on a glass substrate in the form of a grid and non-grid (parallel lines). We have rotated the needle module in order to increase the number of C-MLAs. With this scheme, we have fabricated the 150 mm × 150 mm anti-Moiré filters where 836 microlens lines are formed. They show the average width of 255.4 ㎛, the average distance between CMLs of 94.6 ㎛, and C-MLA width non-uniformity of 4.7%. We have shown that the Moiré patterns still appear in the presence of the parallel (non-grid)-type filter, whereas they disappeared completely by the grid-type filter. It is due to the fact that the Moiré patterns are diffused more effectively by the grid-type C-MLA.

• Journal of the Korea Computer Industry Society
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• v.7 no.5
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• pp.495-502
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• 2006

This paper describes how to implement reporting system for web-based information system. Reporting system is the S/W module that user is able to produce output of data in formal format. In Client/Server system, remote user can make formal output with client-side reporting component module. This client reporting component is usually system dependent. With web based information system, intranet, evolving, this client/server system need to he migrated to web-based reporting system. Reporting system component support multi-processing and real-time text/graphic output of server data. Ant Client can save or pint web page of client module. Especially, for real test its function and user interface, this reporting component is adopted in real network management system. The result shows that this reporting system component is very smart and excellent for real time web based monitoring system.

• Journal of Engineering Education Research
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• v.3 no.1
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• pp.84-91
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• 2000

Modern times are called 'the system and fusion era'. One system has been compounded with the other system repeatedly, and the new systems form a great mixed system again and again. Discrete electronic devices have been integrated as one semiconductor system and have been unified as a great mixed system frequently. This study proposes a module based 2-year college electronic engineering curriculum focused on system and integrated circuit design. This curriculum is devised to be suitable for the industrial environment, especially in the school-industry cooperation, and is recomposed to promote the organic union of interdisciplinary courses. The newly designed course has been developed as a multi semester module model which enables a practical field training and in-depth study.

• KIEAE Journal
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• v.17 no.1
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• pp.55-61
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• 2017

Purpose : As the necessity of reinforcement of infections management in medical facilities after MERS increased, Ministry of Health and Welfare promulgated the enforcement regulations of medical law on February 3, 2017. Its main objective is to improve patients' safety and medical-care quality through the establishment of isolation facilities from infectious diseases and the set-up of standards for In-patient and ICU facilities. The purpose of this study is necessarily to propose a standardized spatial composition model for ward modules by analyzing changing environments of in-patient facilities according to the strengthened medical law. Method: Theoretical studies will be undergone of Evidence-based Designs to improve patients' safety, medical quality, and domestic/overseas in-patient room guidelines. With reference to the status of 24 general hospitals over 500 beds, the spatial compositions of the in-patient rooms and the types of multi/single bed room modules will be analyzed. The directions of future in-patient room module changes through the study of the minimum ward module types and various ward types will be presented. Result: This paper will hopefully provide guidelines for hospitalization rooms that can be applied to the revised rules of medical law enforcement and provide a basis for a comprehensive study of patients' safety and efficient infection control as well.

• Journal of the Korean Society for Precision Engineering
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• v.27 no.2
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• pp.34-39
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• 2010

In order to achieve and maintain dimensional accuracy in laser micro-machining, dominant parameters such as laser power and laser focus position need to be monitored and controlled real time. Also, in order to selectively machine multi-layered materials, the material being presently machined need to be recognized. This paper presents an auto-focusing (AF) module to keep laser focus on a large-area surface; a real-time laser power stabilizing module based on optical attenuation; and a laser-induced breakdown spectroscopy (LIBS) module. With these monitoring modules, position error in laser focus on a 4" silicon wafer was kept below $4{\mu}m$, initially $51{\mu}m$, and laser power stability of a UV laser source was improved from 1.6% to 0.3%. Also, the material transition from polyimide to copper in machining of FCCL (flexible copper clad laminate) was successfully observed.