• Journal of Aerospace System Engineering
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• v.11 no.5
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• pp.65-75
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• 2017

This study proposes development of 3U CubeSat standard platform whose function and performance are verified via KAUSAT-5 development. 3U CubeSat platform specification was selected for the design of 3U Cubesat standard platform by examining existing CubeSat and state-of-art technology, and consequently a universally usable 3U CubeSat platform was designed. Standard platform was manufactured in 1.5U size and developed with a modular concept to be able to add and expand payloads and ADCS actuators for meeting the user's needs. In addition, in case of the power system, the solar panel, the battery, and the deployment mechanism are designed to be configured by the user. In the mechanical system design of a standard platform, subsystem and micro equipment functions/performance could be integrated and miniaturized on micro-sized PCBs and maximized electrical capability to accommodate multiple payloads. In the development of the 3U CubeSat, the satellite platform adopts the developed standard platform, which can reduce the cost and schedule for the whole satellite development by reducing the additional function verification.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.24 no.9B
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• pp.1643-1651
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• 1999

Video-On-Demand (VOD) is expected to provide the user with interactive operations such as VCR functions. In particular, fast scan functions like “Fast Forward” of “Fast Backward” for a certain speedup playback are required. Since they require a significant amount of system resources, schemes to reduce bandwidth requirements for the network or disk are needed. In MPEG standard, Group-of-Pictures (GoP) is a random access unit which can be decoded independently. Since storing and transmitting a video stream based on GoP is efficient, it is practical to support fast scan functions based on GoP. In this paper, we present a dynamic transmission scheduling scheme to support fast scan functions with m-times normal playback rate for a stored video. The proposed scheme writes a transmission schedule whenever user requests a fast scan function. That is, the scheme constructs the data set to be smoothed by skipping GoPs according to a given speedup factor, and then writes the transmission schedule by applying a bandwidth smoothing. Finally, the scheme restarts the transmission of video data to a client according to the new schedule. The proposed scheme results in speeding up the playback rate by utilizing “GoP skipping”, and then reduces the computational overhead by applying a bandwidth smoothing based on GoP.

• Journal of the Korean Wood Science and Technology
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• v.14 no.1
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• pp.45-54
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• 1986

A study was conducted to determine the physical properties related to drying characteristics, the seasonal air drying curves and the kiln drying schedule for taun lumber imported and utilized. This kiln drying schedule was found by oven drying and developed by pilot testing of green lumber and partially air dried lumber. The results of this study were as follows; 1. Average green specific gravity and standard deviation of heartwood lumber were 0.60${\pm}$0.03 and those of sapwood lumber were 0.64${\pm}$0.02. 2. Radial shrinkage from green to air dry and from green to oven dry were 3.05 percent and 5.96 percent respectively, and tangential shrinkage from green to air dry and to oven dry were 5.49 percent and 8.74 percent respectively. 3. Drying time for 25mm thick green lumber (50 percent moisture content) air dried to 30 percent moisture content were 14 days in springtime. 6 days in summertime, and 12 days in autumntime, whereas for 50mm thick lumber in 36 days in springtime, 18 days in summertime, 38 days in autumntime. 4. Kiln drying schedules developed by oven drying were T8-B3 for 25mm thick lumber and T5-B2 for 50mm thick lumber. 5. Kiln drying curves of green 25mm and 50mm thick lumber were similar to those of partially air dried lumber from the level of 30 percent average moisture content. Green 25mm thick lumber (55.7 percent moisture content) was dried to 9.3 percent moisture content in 101.5 hours and green 50mm thick lumber (65.6 percent moisture content) was dried to 11.5 percent moisture content in 526 hours. 6. End checking for green 25mm thick lumber occured in 49.6 percent moisture content and reached maximum amount in 27.6 percent moisture content and closed in 15.8 percent moisture content. 7. End checking for green 50mm thick lumber and partially air dried lumber developed and reached maximum amount earlier then for 25mm thick lumber. 8. Final moisture content of surface layer for 50mm thick lumber was one half of that of core, and moisture content equalized in the lumber after nine days of room conditioning. 9. Casehardening for 50mm thick lumber was slight and was conditioned after nine days of room stroage. 10. Drying defects, such as end checking and surface checking, were not observed and the quality of dry lumber was first.

• Korean Journal of Construction Engineering and Management
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• v.24 no.5
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• pp.52-62
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• 2023

The objective of this study is to propose an automated algorithm for precise cutting length of slab rebar complying with regulations such as anchorage length, standard hooks, and lapping length. This algorithm aims to improve the traditional manual quantity take-off process typically outsourced by external contractors. By providing accurate rebar quantity data at BBS(Bar Bending Schedule) level from the bidding phase, uncertainty in quantity take-off can be eliminated and reliance on out-sourcing reduced. In addition, the algorithm allows for early determination of precise quantities, enabling construction firms to preapre competitive and optimized bids, leading to increased profit margins during contract negotiations. The proposed algorithm not only streamlines redundant tasks across various processes, including estimating, budgeting, and BBS generation but also offers flexibility in handling post-contract structural drawing changes. In particular, the proposed algorithm, when combined with BIM, can solve the technical problems of using BIM in the early phases of construction, and the algorithm's formulas and shape codes that built as REVIT-based family files, can help saving time and manpower.

• Journal of Oral Medicine and Pain
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• v.30 no.2
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• pp.257-268
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• 2005

It is recently suggested in Korea that Resource-Based Relative Value Scale (RBRVS) is an alternative plan of Korean Dental Fee Schedule which has been operated on a fee-for-service basis since the introduction of the national health insurance program in 1977. RBRVS applicable to diagnosis and treatment for temporomandibular disorders (TMD), a common cause of orofacial pain, is needed to be estimated in Korea and the establishment of the standard terminology of dental procedures for TMD should be preceded. The purposes of this study were to develop a new classification system of health care service items for TMD and to investigate time needed for each item, which enables RBRVS to be estimated prior to establishment the payment system of health care services for TMD. The dental service items for TMD in this study were categorized through Delphi process which 10 TMD specialists were participated in and the time needed for each service item was investigated by work sampling and time study method with a stopwatch. The results of this study demonstrated the new classification system of dental services for TMD comprising 151 service items and exhibited the average time for each items ranging from 7.22 min for cold laser therapy to 171.71 min for direct fabrication of anterior repositioning splint. Conclusively, it is suggested that the classification system for TMD developed in this study, considering specific characteristics on basis of resources for health care service of dental procedures, should be helpful to estimate payment level for each service item.

• Fashion & Textile Research Journal
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• v.13 no.2
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• pp.269-278
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• 2011

This study aims at setting up productive capacity which can be usefully utilized for work management of apparel manufacturers. So as to achieve this goal, an apparel manufacturing company which has been operated by miniline system in Seoul was selected. Standard time and man-hour were calculated to create the accurate productive capacity by observing and measuring a work flow included cutting, sewing and finishing processes. And the result is as following. The standard time for each process was presented as cutting process 47004.5s, sewing process 671050.5s and finishing process 22426.3s. And 15284.4ms was computed as total procession man-hour per day of the manufacturer which is organized of 16 people. Also, the procession man-hour for each process was revealed as cutting process 396.7ms(2.6%), sewing process 14509.3ms(94.9%) and finishing process 378.5ms(2.5%). +Surplus was found in the productivity for each process included the cutting process(outshell, lining and seam process), the sewing process(preparation and arrangement process) and the finishing process. But, additional man-hour 52436.18ms was required because the productive capacity was calculated as -surplus(-13.9%) in the sewing process(part and assembly process). Therefore, a work schedule was planned based on the previous result. However, loading can be ideal when a capacity and a load become '0'. The object company should find the way to reduce allowance(26.25%) of the sewing process through reconstruction of consciousness and improvement in functions with analyzing works of operators. Also, they need to consider an additional supplement of the personnel.

• Journal of the Korean Society of Safety
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• v.23 no.5
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• pp.119-124
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• 2008

Many automobile assembly workers often do several cycles of tasks continuously, i.e., without breaks, to get a longer break. This is not recommended since the dose of fatigue increases exponetially with time and it takes much longer time to recover. In this study, a laboratory experiment was conducted to investigate the effect of work/rest schedules on workload of a repetitive upper-limb task. Eleven male subjects participated in the experiment, in which simulated screw driving tasks were carried out repetitively with 3 different work/rest schedules: standard breaks(1 cycle of work at a time, 60 20-s breaks), medium breaks(5 cycles of work at a time, 12 100-s breaks), and long breaks(10 cycles of work at a time, 6 200-s breaks). The result showed that medium- and long-breaks schedules significantly increased the level of perceived discomfort and %HRR as compared to the standard-break schedule. The subjects' preference was not statistically different among work/rest schedules, which might be caused from the absolutely low level of workload of the experimental tasks. From the results, it is recommended to have frequent and shorter breaks rather than infrequent and longer breaks to decrease the level of physical workload. A more expanded studies, however, should be carried out to provide more practical safety guidelines on the work practice of continuous working without breaks among automobile assembly workers.

• The Journal of Korean Obstetrics and Gynecology
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• v.20 no.3
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• pp.213-228
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• 2007

Purpose: This master‘s thesis to evaluate the grade of life after medication a Dangguijakyak-san(pasabu) and Gyejibongnyeong-hwan(cheongwal) with in postmenopausal women get lowering quality of life caused by vasomotor symptoms with hot flush. Methods: A subject who signing on the clinical trial written consent by self-will is registered this clinical trial after decided suitable by selection and exception standard, after take a medical experiment and checkup according to clinical trial plan. Registered subject should valuated by settled schedule after take the testing medicine 1,2 during thirty-day. In this period, a subject allocated at relatively better suited experimental group by oriental doctor after consideration of general efficacy and nature of a medicine at second visiting. Results: The result of comparison in the remedial value with sixteen patients who ended the experiment is like next list. 1. There's no regarded difference of comparison in general conditions between two patient groups. 2. There's no regarded difference during observation period before take medicine. 3. By period of measurement, there's something regarded differences most of patients of two parts after taking medicine. 4. There's no regarded difference at alteration phase of each standard according to kind of medicine. 5. There's no abnormal views reflected at allergy, Laboratory and Physical Examination during experiment. Conclusion: This experiment evidence a Dangguijakyak-san and Gyejibongnyeong-hwan can help for improvement generally life quality of postmenopausal women and certify safety of herbs.

• The Transactions of the Korea Information Processing Society
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• v.5 no.4
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• pp.1005-1013
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• 1998

In this paper, we describe technologies of Intranet administrator and user application used in the PEC(Protocol Engineering Center) Office Intranet system which provides platform independent application framework using Internet/Intranet standard technologies for distribution of Web documents and real-time multimedia information. The PEC Office is composed of administrator applications to support environments for administration of all applications including group/user add, update, and delete facilities and construction of user directory and user applications to support schedule sharing, virtual library, job report, output management, budget management, and real-time audio/video broadcasting services. These applications allow differentiation and customization services according to department and title employed per users.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.2164-2168
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• 2003

Real time control system such as in factory automation fields, defense field, aerospace, railway industries, financial trading and so forth, includes multiple computers on multiple nodes, and share data to process various actions and functions. This is similar to multitasking in a multiprocessor computer system. The task processing efficiency of such system is proportionally increased by process speed of each process computer. And also it is greatly influenced by communication latencies of each node. To provide proper operation of such real time system, a network that can guarantee deterministic exchange of certain amount of data within a limited time is required. Such network is called as a real time network. As for modern distributed control system, the timeliness of data exchange gives important factor for the dynamics of entire control system. In a real time network system, exchanged data are determined by off-line design process to provide the timeliness of data. In other word, designer of network makes up a network data table that describes the specification of data exchanged between control equipments. And by this off-line design result, the network data are exchanged by predetermined schedule. First, this paper explains international standard real time network TCN (Train Communication Network) applied to the KHST (Korean High Speed Train) project. And then it explains the computer program developed for design tool of network data table of TCN.