• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1995.11a
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• pp.115-115
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• 1995

다중 효용관식 증발기는 보통의 증발기에서 응축하여 제거하는 증기를 다음 효용관의 가열원으로 재사용하는 것으로 그 자체로도 에너지 절감효과가 있는 것으로 알려져 있다[1,2,4]. 기계식증기 재압축 증발기는 보통 증발기에서 응축시켜 제거하는 발생 증기를 압축하여 고온의 증기로 만든 다음 가열원으로 재이용하는 장치로 이에 대한 효용은 문헌에 잘 나타나있다[3,4]. 여기서는 다중효용관과 증기 재압축기를 조합한 증발기 중에서 Forward feed 방식의 다중효응관에 증기 재압축기를 부착한 경우에 대하여 타당한 물질수지, 열수지, 전열 식, 상평형식을 소개하였다. 또한 압축기의 용량을 결정하기 위한 단열압축공정의 지배방정 식을 소개하였다. 원료의 조건, 효용관의 수 및 총전열온도차가 주어지면 상기의 지배방정식의 해를 구할 수 있는데. 본연구에서는 Gauss-Seidel의 연속치환법을 이용하였다. 이와 같이 지배방적식의 해를 구하면 효용관의 면적, 압축펌프의 용량, 각효용관 입출구의 조건 등이 계산된다. 다중효용관 기계식 증기 재압축 증발장치의 최적화를 위하여는 효용관의 전열면적당 가격과 압축펌프의 용량당 가격 그리고 펌프를 운전하는데 필요한 전력의 요금 등의 자료가 요구된다. 총전열온도차에 따른 운전비와 시설비의 합이 최소가 되는 점이 최적 총전열온도차가 되는데 이 점을 구할 때에는 수치적으로 안정한 이분법을 이용하였다. Borland C++를 이용하여 프로그램하였으며 윈도우즈 환경에서 수행되게 하였다. 사용자 쉽게 이용할 수 있게 하기 위하여 각종 필요한 데이터를 입력할 수 있는 Edit box가 화면에 나타나게 하였다. 또한 입력된 데이터를 저장하거나 불려올 수 있는 메뉴, 입력된 데이타를 이용하여 효용관의 면적과 압축기의 용량을 계산하거나 효용관의 수가 주어졌을 때 총전열온도차를 최적화하는 것을 선택할 수 있는 메뉴 그리고 계산 결과를 파일로 혹은 프린트로 출력할 것을 선택할 수 있는 메뉴가 있다. 사용자는 해당되는 데이타를 입력한후 마우스로 원하는 작업의 메뉴를 선택하면 된다.

• Archives of design research
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• v.12 no.1
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• pp.15-24
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• 1999

The deVelopment of technologies changes the thinking of people and the ways of IMngs. The software developers as well as users are now aware of the importance of graphic user interface design, and the usage of graphic elements is getting rrore and more easier due to the technological improvements based on the windows system(Microsoft). For these reasons, people who engaged in software developments do much more efforts to get user-oentered design solutions, in other words, the usability improvements. And the interdisciplinary projects teams which consist of experts of various fields are increasing in number. But, the lack of understanding on software developments and the proceeding of design work without the consideration of entire process of a project make interface design work difficult. For exampIe, some engineers often think designers as persons who decorate their products in the final stage. In this thesis, through the investigation of user interface design and software development process, the frarnework of effective team projects is proposed. The main purposes of this thesis are to define the work area and position of designers and to propose the interface design process for the cooperative software development projects within the interdiociplinary teams.

• Journal of Digital Convergence
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• v.14 no.8
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• pp.261-267
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• 2016

In this paper, we studied the range-free localization algorithm between sensor nodes based on the Radical Line for sensor networks. Routing in wireless sensor networks should reduce the overall energy consumption of the sensor network, or induce equivalent energy consumption of all the sensor nodes. In particular, when the amount of data to send more data, the energy consumption becomes worse. New methods have been proposed to address this. So as to allow evenly control the overall energy consumption. For this, the paper covers designing a localization algorithm that can obtain the location information of the peripheral nodes with fewer operations. For the operation of the algorithm is applicable Radical Line. The experimental environment is windows 7, the Visual C ++ 2010, MSSQL 2008. The experimental results could be localized to perform an error rate of 0.1837.

• Journal of Korean Society of Forest Science
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• v.88 no.1
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• pp.63-72
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• 1999

In this study, a relational database program to manage the data involved in forest planning was developed in such a way to simulate the whole process of 'Younglim' planning in Korean National Forest System. Using the pull-down menu system of various functions required for developing 'Younglim' plan, the database program can handle the data of forest inventory, 10-year working plans, annual working plans and the history of forest operations automatically and simultaneously. The model was designed to run under the environment of Korean version of Windows 95. Visual Basic 5.0 was used as the basic tool for programming and Microsoft ACCESS as the basic engine of the database system. In this paper, the process of designing the structure of database program following the process of 'Younglim' plan and the structure of the model are discussed. In addition, the functions of menu system are presented using the screen-mode output windows of the model.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.12
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• pp.2926-2932
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• 2014

Smart Phone market consists of several platforms such as Windows Phone, Apple iOS and Android of Google. Each platform uses different coding style respectively. Platform-dependent application results in high cost and low code reusability during development of application. It also provides heterogeneous display forms to users. In this paper, we propose a platform-independent generic interface model that could be operated in both the various smart phones and PC. Because the proposed model provides the same UI on multiple platforms, users can operate applications without awkwardness. The model includes a module which copes with the changes of the resolutions in various platforms and a module which switches scenes of each application for performance improvement. Moreover, a module which connects DB is also proposed in order to overcome the difference of way to store data in each platform. The implementation results show that the difference of display and operating manner in any hetero-platform is eliminated.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.7
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• pp.1599-1609
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• 2014

TCP does not ensure the bandwidth and delay bound required for multimedia streaming services in broadband wireless network environments. In this paper, we propose a new congestion control scheme for efficient multimedia transmission, called COLO TCP (Concave Increase Slow Start Logarithmic Increase Congestion Avoidance TCP). The COLO TCP prevents the burst packet loss by applying the concave increase algorithm in slow start phase. In the congestion avoidance phase, COLO TCP uses the logarithmic increase algorithm that quickly recovers congestion window after packet loss. To highly utilize network bandwidth and reduce packet loss ratio, COLO TCP uses additive increase algorithm and adaptive decrease algorithm. Through simulation results, we prove that our COLO TCP is more robust for random loss. It is also possible for efficient multimedia transmission.

• Convergence Security Journal
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• v.13 no.6
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• pp.25-33
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• 2013

Digital certificate must be used for electronic financial transactions in Korea. But because digital certificate is based ActiveX of Internet Explorer, it is difficult to use digital certificate in other web browsers. It interrupts a development of various authentication technology and a growth of related industry. Also digital certificate can be leaked because of being stored in harddisk or USB. The government eased obligatory use of digital certificate and opened doors to other authentication techniques. But any other authentication techniques are not used because they are not approved as alternative technology. The revised bills with digital certificate abolition as the main agenda have been submitted to the National Assembly. Whether the revised bills pass or not will be decided by a regular session of the National Assembly depending on the calculation and dynamics composition of related industry. In this paper, a controversy over obligatory use of digital certificate is examined and measures are found.

• Journal of IKEEE
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• v.21 no.4
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• pp.358-367
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• 2017

Advanced Driver Assistance Systems(ADAS), such as Front Collision Warning System (FCWS) are currently being developed. FCWS require high processing speed because it must operate in real time while driving. In addition, a low-power system is required to operate in an automobile embedded system. In this paper, FCWS is implemented in CPU-FPGA architecture in embedded system to enable real-time processing. The lane detection enabled the use of the Inverse Transform Perspective (IPM) and sliding window methods to operate at fast speed. To detect the vehicle, a Convolutional Neural Network (CNN) with high recognition rate and accelerated by parallel processing in FPGA is used. The proposed architecture was verified using Intel FPGA Cyclone V SoC(System on Chip) with ARM-Core A9 which operates in low power and on-board FPGA. The performance of FCWS in HD resolution is 44FPS, which is real time, and energy efficiency is about 3.33 times higher than that of high performance PC enviroment.

• Journal of the Korean Association of Geographic Information Studies
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• v.5 no.3
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• pp.33-44
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• 2002

The water resources information system of a watershed should be set up to understand the water management problems with reflecting basin characteristics for the effective water use. This study is to develop a watershed management system to be operated in water resources and water quality management. In order to promote effective utilization of this system, the various kinds of information data are collected, and this system could be utilized as a valuable tool for maximum uses of them. The information system developed in this study is constructed with GUI(graphic user interface) system using Arc-View and Visual Basic at the circumstances based on the PC. The integrated GIS and Remote Sensing based system is directed to the need for more detailed information on watershed management. The ability to present system clearly provides an indispensable tool for a river basin development and water management plan.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.19 no.2
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• pp.137-146
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• 2001

Route selection needs the analysis function of GSIS to analyze and manipulate a lot of spatial information efficiently. Therefore, it needs the linkage of system requiring the knowledge and the experience of experts as a method that can estimate each quantitative route for an efficient route selection. In this study, the route selection model through construction and analysis procedure of position information using GSIS were presented, and route selection system linked with expert system was developed. This system is easy to be used and managed for presenting route alignment according to conditions as a graphic user interface environmental window system by applying three tiers based object-oriented method. Using GSIS, the various information required for route selections in database was constructed, the characteristics of subject area by executing three-dimensional terrain analysis was grasped effectively, and the control point through buffering, overlay and location operation was extracted. Three alternative routes between a beginning point and an end point inputted by route selection system were selected. Therefore, the applications of the route selection system are presented by applying this system to the real study area.