• Title/Summary/Keyword: 변경 영향 분석

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An Efficient Multipath Routing with Dynamic Load Balancing (효율적인 동적 부하 균등 분산을 적용한 다중 경로 라우팅)

  • Jung, Sun;Lee, Mee-Jeong
    • Journal of KIISE:Information Networking
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    • v.28 no.3
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    • pp.406-416
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    • 2001
  • Single path routing schemes using dynamic routing metric amy find out the dynamic network status and recompute paths to keep the traffic from the highly loaded regions of the network. This type of routing approach, however, may lead to a routing oscillation, and further, it cannot exploit multi-paths that may frequently exist in the real network. We propose a multipath routing scheme with dynamic load balancing, called MP-DLB, which is capable of reducing the overhead incurred by the multipath routing with dynamic load balancing approach while taking advantage of the high routing performance provided by the approach. According to the analysis of Internet packet traces which show that a high percentage of network traffic is destined for a small number of networks, MP-DLB applies the multipath routing with dynamic load balancing only to a limited subset of all the destinations in the network. For the rest of the destinations, it applies traditional single path routing scheme. This approach may reduce overall routing overheads by limiting the number of destinations to apply the more complicated routing scheme while it can keep the routing performance high by providing efficient routing for the most significant traffic in the routing performance. A series of simulations are done to analyze the performance of MP-DLB. The simulation results show that MP-DLB may effectively cope with the congestion and achieve high routing performance by distributing traffic streams that are generated from varying sources and heading toward a specific hot destination over multi-paths.

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A Study on the Development Environment for Flight Software using PowerPC (PowerPC를 이용한 저궤도 위성용 탑재소프트웨어 개발환경에 대한 연구)

  • 이재승;최종욱;김대영;이종인;김학정
    • Proceedings of the Korean Information Science Society Conference
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    • 2004.10c
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    • pp.514-516
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    • 2004
  • 위성의 개발을 위해서는 오랜 개발기간과 많은 예산, 축적된 기술이 요구된다. 또한 위성에는 다양한 분야의 기술이 사용되어지기 때문에 각 서브시스템마다 독자적인 개발환경을 구축할 필요가 있다. 특히 위성의 찌어. 임무수행 및 지상과의 통신 등을 담당하는 탑재소프트웨어는 위성의 용도 및 목적에 따라 개발환경이 크게 달라진다. 실시간 운영체제는 무엇을 사용하는지, 개발 및 검증을 위한 도구로 어떤 프로그램을 사용하는지, 내외부의 인터페이스는 어떠한 방식으로 수행할지, 새로운 기능의 CPU나 하드웨어에 대한 제어 등 위성의 탑재소프트웨어를 개발하기 위해서는 많은 검토 항목들이 고려되어야 한다. 새로운 위성을 개발할 경우 신기술의 적용과 새로운 시스템위성시스템의 검증 및 개발을 위한 개발검증장비가 요if되며, 위성시스템의 변경 때마다 개발검증장비를 새로이 구축하게 되면 많은 기간과 막대한 비용이 위성개발 시마다 소요된다. 위성선진국에서는 다양한 위성의 개발 시 비용절감 및 개발기간 단축을 위하여 범용위성용 개발검증장비를 개발하여 이용하고 있는 추세이다. 국내에서는 다목적실용위성 1호가 발사되어 성공적으로 임무를 수행하고 있으며 다목 실용위성 2호가 개발되어 현재 통합 및 조립시험이 진행 중이다. 그러나 새로운 위성시스템의 사전 검증 및 신기술의 적용을 위한 범용위성 시스템 테스트베드에 대한 기술은 미비한 실정이다. 이러한 범용위성용 개발검증장비의 기반기술을 확보하기 위하며 현재 위성전자전산시스템 개발검증장비에 대한 연구가 수행되고 있다. 본 논문에서는 현재 수행되고 있는 PowerPC를 이용한 위성 탑재소프트웨어 개발검증시스템의 설계 및 개발현황에 대하여 소개한다.이스는 실험정보가 저장된 데이터베이스, 분석결과가 저장된 데이터베이스, 그리고 유전자 정보 탐색을 위한 데이터베이스로 분류해 데이터를 효율적으로 관리할 수 있게 하였다. 본 시스템은 LiNUX를 운영체계로 하고 데이터베이스는 MYSQL로 하여 JSP, Perl. 통계처리 언어인 R로 구현되었다.프트웨어를 사용하지 않고도 국내의 순수 솔루션인 리눅스 기반의 LonWare 3.0 다중 바인딩 기능을 통해 저 비용으로 홈 네트워크 구성 관리 서버 시스템 개발에 대한 비용을 줄일 수 있다. 기대된다.e 함량이 대체로 높게 나타났다. 점미가 수가용성분에서 goucose대비 용출함량이 고르게 나타나는 경향을 보였고 흑미는 알칼리가용분에서 glucose가 상당량(0.68%) 포함되고 있음을 보여주었고 arabinose(0.68%), xylose(0.05%)도 다른 종류에 비해서 다량 함유한 것으로 나타났다. 흑미는 총식이섬유 함량이 높고 pectic substances, hemicellulose, uronic acid 함량이 높아서 콜레스테롤 저하 등의 효과가 기대되며 고섬유식품으로서 조리 특성 연구가 필요한 것으로 사료된다.리하였다. 얻어진 소견(所見)은 다음과 같았다. 1. 모년령(母年齡), 임신회수(姙娠回數), 임신기간(姙娠其間), 출산시체중등(出産時體重等)의 제요인(諸要因)은 주산기사망(周産基死亡)에 대(對)하여 통계적(統計的)으로 유의(有意)한 영향을 미치고 있어 $25{\sim}29$세(歲)의 연령군에서, 2번째 임신과 2번째의 출산에서 그리고 만삭의 임신 기간에, 출산시체중(出産時體重) $3.50{\sim}3.99kg$사이의 아이에

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Preliminary Study on Factor Technology of Selective Catalytic Reduction System in Marine Diesel Engine (선박용 디젤엔진 SCR 시스템 요소 기술에 관한 기초 연구)

  • Park, Yoon-Yong;Song, Ha-Cheol;Ahn, Gi-Ju;Shim, Chun-Sik
    • Journal of Navigation and Port Research
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    • v.40 no.4
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    • pp.173-181
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    • 2016
  • From 2016, controls on reduction of NOx and SOx emissions from the vessels that are operated in the emission control area were tightened. The selectivity catalytic reduction system of the denitrification equipment which NOx among the above controlled materials is very effective and used commercially very much. But it has the disadvantage that CSR is activated at high temperatures. Therefore, the SCR and SCR activation instrument that can react even at low temperatures by using micro-nano bubbles so that the above problems can be minimized were developed. And the computational fluid dynamics technique was used by ANSYS-CFX package to prepare the plan that improves the SCR system's efficiency. Simulation for the viscous flow analysis of the SCR system was executed by applying the Navier-Stokes equation to it as a governing equation. For the SCR system's shape, 3D modeling was done by using CATIA V5. SCR jet nozzle's position was checked by changing it to the intervals of 1/3, 1/2, and 2/3 from the inlet of the vent pipe to compare the SCR system's efficiency. And the number of nozzles was compared and analyzed by simulating 4, 6, and 8 holes to check an effect of the number on the SCR system's efficiency. The simulation result has found that the closer nozzles are to the inlet of the vent pipe and the more nozzles are, the more efficiency is improved.

A Study on the Post-Evaluation of Landscape Design Competition based on Ground Theory - Case of Gwanggyo Lake Park in Korea - (근거이론을 활용한 조경현상설계의 사후평가 - 광교호수공원을 사례로 -)

  • Hong, Youn-Soon;Park, Jae-Min
    • Journal of the Korean Institute of Landscape Architecture
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    • v.44 no.5
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    • pp.92-102
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    • 2016
  • While there have many completions of large parks recently under development, there has been a dearth of quality assessments. Studies focused on post-evaluation have been made to resolve this, but most of these are biased toward user satisfaction after completion and therefore behaviour analysis has limitations on solving problemsduring the actual design implementation processes. Therefore, this study examined the internal phenomenon and structure of the implementation process of design competition through the ground theory and microscopic independent perspective. As a result, maintaining the identity and differentiation of parks derived from the preserved design competition scheme contributed greatly to completeness and satisfaction. Outcomes were mainly caused by the trust of public officials as the ordering organization, the will of policy decision-makers, and the competence of operational enterprises, etc. Negative factors such as undermining the whole concept of the park and landscape occurred as external pressure and related subjects intruded on change design factors due to variations in social conditions. Additionally, illogical construction processes occurred, such as a reinvestigation of the budget for restoration after damaging on original landscape. There have been needs for the improvement of the work processing system. On balance, an interventional role is very important in the park construction process, especially the PA and operation committee in terms of maintaining the basic direction, landscape design supervision for detailed designs, and expert construction management on LA in terms of rational work management in the field. The study, using the microscopic perspective of the designer and ground theory, deliver significant meaning as an early study by suggesting alternative methods for the after-evaluation of large parks and structurally looking into main influence factors driven during the construction process.

Measures to Implements the Landscape Conservation and Management in the Seowon Hamyang Namgye inscribed on the World Heritage List (세계유산 등재대상 함양 남계서원의 경관보존관리방안)

  • Choi, Jong-Hee;Moon, Young-Suk;Kim, Dong-Hyun
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.31 no.2
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    • pp.128-135
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    • 2013
  • The purpose of this study is a suggestion that it is a way for conservation and management the Namgye Seowon's heritage value based on its landscape visibility and land use; Namgye Seowon is a world heritage registration object. To do this, We had done a field investigation and a literature examination. The investigations are as following; first, setting protection zone through a comprehensive approach beyond uniform cultural properties protection zone is to note current intellectual situations as well as the place related to the locational characteristics and figures of Namgye Seowon. It's to set fore seeable section of landscape by analyzing visibility focusing through on Pungyeongnu, and it consider with protection zone and the present condition of land use. Especially, external view of landscape in Namgye Seowon is visualized with Baekam-san in the distance view of it and Cheonhwang-bong in Daebong-san and nearby large soundproof walls and the towers acts as an impediment factor to the view of landscape. In addition, to recover the original view of landscape of the Namgye Seowon, reckless plans focusing the authenticity of the world heritage should be limited and in case of the vegetation landscape, restoration and maintenance will be made through historical research literature. Through this study, researches on Namgye Seowon and several seowons will be done actively and its aims are to become the framework of landscape conservation and management measures to meet world heritage criteria.

Suggestion of The Manual Exposure Condition Guideline for Reducing Patient Dose in Digital Breast Tomosynthesis (디지털 유방단층촬영의 피폭선량 경감을 위한 수동 촬영조건의 가이드라인 제시)

  • Hong, Eun-Ae;Lee, In-Ja
    • Journal of radiological science and technology
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    • v.39 no.4
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    • pp.483-491
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    • 2016
  • The conditions after exposure to digital mammography and digital breast tomosynthesis were analyzed. The examinations for the ACR phantom were done using manual exposure, not auto exposure, to examine image discrimination and patient dose. As a result, the following results were derived: In the CC exposure, the kVp was 2kVp higher while mAs decreased to 58.6% for the 3D tomography. Such result showed an approximate decrease of 60mAs. At that time, the patients' Average Glandular Dose (AGD) was 1.65mGy in 2D and 1.87mGy in 3D; thus, AGD of 3D was shown to have about 1.13times higher. The result of the manual exposure revealed a reduced mAs of up to 80%; there was no effect in the assessment standard in terms of image discrimination, resulting in more than 10 points. When mAs was reduced to 80% in the manual exposure for ACR phantom, AGD was decreased to 0.66mGy. The diagnostic values of images were maintained and patients dose was reduced in the manual exposure in the AEC condition for 3D. Since the use of 3D has recently increased, using the manual exposure has been recommended in this study to improve the diagnostic value, while, simultaneously reducing patients dose.

The Korean Geodetic Network Adjustments for EDM Area (국가기준점 망조정에 관한 연구 - EDM 관측지역)

  • Yang, Hyo-Jin;Choi, Yun-Soo;Kwon, Jay-Hyoun;Kim, Dong-Young
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.25 no.5
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    • pp.393-398
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    • 2007
  • According to the Korean datum change to a world geodetic system, the EDM area should be readjusted to provide consistent product over the country. The data set for EDM area is extracted from the previous KTN1987 DB and checked for the moved markers in XY network adjustment which provides quality verification. Then, EDM data set for the seven areas are rebuilt for the adjustment. Since the data is still based on the old datum, the coordinates of the data are transformed by applying the coordinate transformation parameters. Here, the transformation parameters, which were determined for the conversion of 1:50,000 topographic maps by NGII, were used. For each EDM point, the geoidal height from EGM96 model is applied to obtain the ellipsoidal height based on the GRS80. The measured distance projected onto GRS80 is adjusted using BL network adjustment by fixing 2nd order or 3rd order GPS control points. The results from the readjustment show the minimum standard error of 1.37" and the maximum standard error of 2.13". Considering the measurement accuracy of EDM (1.6" corresponding to about 2cm) and GPS position for fixed points (2cm), this result is considered to be reasonable and it is good for the practical use.

Development of a Workload Assessment Index Based on Analyzing Driving Patterns (운전자 주행패턴을 반영한 작업부하 평가지표 개발)

  • KIM, Yunjong;LEE, Seolyoung;CHOI, Saerona;OH, Cheol
    • Journal of Korean Society of Transportation
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    • v.35 no.6
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    • pp.545-556
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    • 2017
  • Various assessment indexes have been developed and utilized to evaluate the driver workload. However, existing workload assessment indexes do not fully reflect driving habits and driving patterns of individual drivers. In addition, there exists significant differences in the amount of workload experienced by a driver and the ability to overcome the driver's workload. To overcome these limitations associated with existing indexes, this study has developed a novel workload assessment index to reflect an individual driver's driving pattern. An average of the absolute values of the steering velocity for each driver are set as a threshold value in order to reflect the driving patterns of individual drivers. Further, the sum of the areas of the steering velocities exceeding the threshold value, which is defined as erratic steering area (ESA) in this study, was quantified. The developed ESA index is applied in evaluating the driver workload of manually driven vehicles in automated vehicle platooning environments. Driving simulation experiments are conducted to collect drivers' responsive behavior data which are used for exploring the relationship between the NASA-TLX score and the ESA by the correlation analysis. As a result, ESA is found to have the greatest correlation with the NASA-TLX score among the various driver workload evaluation indexes in the lane change scenario, confirming the usefulness of ESA.

A Study on the Estimation of Occupational Safety and Health Expense Rate by Safety Environment Change in Construction Industry (건설산업의 안전 환경 변화에 따른 산업안전보건 관리비 적정요율 산정에 관한 연구)

  • Oh, Se-Wook;Kim, Young-Suk;Choi, Seung-Ho;Choi, Jin-Woo
    • Korean Journal of Construction Engineering and Management
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    • v.14 no.4
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    • pp.97-107
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    • 2013
  • Occupational safety and health management expense in construction industry means the monetary amount that the purchaser appropriates to prevent various disaster from happening during the construction period by setting aside a certain amount from subcontract based on the construction type and scale. The current appropriation standard of the Ministry of Employment and Labor has been enforced since its stipulation in 1988 although various policy changes for the safety in construction industry, e.g. the development of occupational safety management techniques in construction industry, changes in construction field site environment, cost depreciation, etc., are happening in Korea and overseas. Therefore, it is required at this point to examine whether the current occupational safety and health management expense appropriation is proper or not on the basis of time trend and the changes in the construction industry environment. Accordingly, this study aims at investigating the appropriation of occupational safety and health management expense for construction industry by the construction type and target expense in response to current construction industry environment and proposing the proper appropriation. The above research result proposes the calibration of the appropriation as specified and stipulated by the Ministry of Employment and Labor by the construction type and target expense, which is necessary to reflect the actual condition of the current construction industry environment.

A Clinical study of Taeumin Chongsim Yonja Tang (청심연자탕(淸心蓮子湯) 활용(活用)에 대(對)한 임상적(臨床的) 연구(硏究))

  • Park, Seong-sik
    • Journal of Sasang Constitution and Immune Medicine
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    • v.10 no.1
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    • pp.235-252
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    • 1998
  • 1. Background and Purpose : I intended to be helpful to understand constitutional symptoms of a disease and an application of the prescription through a clinical study of Taeumin Chongsim Yonja Tang. 2. Methods : I studied 125 patients(62 men and 63 women) treated with Taeumin Chongsim Yonja Tang in constitutional clinic of Dongguk Pundang Oriental Hospital. And then I investigated the characteristics of Chongsim Yonja Tang treated patients, remedial values and side effects. 3. Results : Taeumin Chongsim Yonja Tang was used in all age groups both men and women. There were 60 kinds of chief complaints including numbness of hands and feet, headache and fatigue etc. The distributions of remedial values were slightly improved(60.8%), much improved(15.2%), no improved(24.0%) and there was no aggravated patient. Using the prescription, mostly I prescribed only Taeumin Chongsim Yonja Tang without any changing, and added 2-3 herbs to the prescription according to the symptoms of a disease. Taeumin Chongsim Yonja Tang was affected in remedial values by the period of sufferring from illness, treatment and medication. Side effects were diarrhea, indigestion and so on.

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