• 대한화학회지
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• 제32권1호
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• pp.71-78
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• 1988

20,21,24,25-Tetranitrodibenzo-18-crown-6에 알코올성 염기를 가하여 친핵성 치환반응을 유도하면 crown ether 화합물을 이루는 polyether 고리가 끊어져서 주생성물로 2,4,5-trialkoxynitrobenzene 유도체, 4,5-dialkoxy-1,2-dinitrobenzene 유도체 그리고 crown ether 고리가 부분적으로 끊어져 생긴 bis[(alkoxynitrophenoxy)ethyl]ether 유도체가 부생성물로 얻어졌다. 이가 알코올성 염기에서는 polyether 고리가 끊어진 생성물과 분자내 치환반응이 다시 진행되어 고리축소 현상이 일어나 12-crown-4의 유도체를 얻게 되거나 출발물질이 도로 생성되었다. 이상의 실험은 다양한 알코올의 농도에서 염기의 종류를 달리하여 그 선택성을 알아보았다.

• Tribology and Lubricants
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• 제24권6호
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• pp.320-325
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• 2008

The recent industrial application requires technical methods to get the cutting fluid droplet surfaces in particular from the viewpoint of topography and micro texture. To characterize the surface topography of droplet, the combination of the confocal laser scanning microscope (CLSM) and wavelet filtering is well suited for obtaining the droplet geometry encountered in tribological research. This technique indicates a better agreement in obtaining an appropriate droplet surface obtained by the CLSM over a detail range of surface accuracy (resolution: $2{\mu}m$). And the results allow an excellent accuracy in a measurement of a droplet surface. The combination of extended focal depth measurement configured and multi-scale wavelet filtering has proven that it can construct a droplet surface in a successive and accurate way. A multi-scale approach of wavelet filtering was developed based on the decomposition and reconstruction of droplet surface by 2D wavelet transform using db9 (a mother wavelet of daubechies). Also this technique can be extended to characterize the quantification of droplet properties and other field in a wide range of scales. Finally this method is verified to be a better droplet surface modeling in a micro scale arising in a mist machining.

• 한국통신학회논문지
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• 제30권10C호
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• pp.983-991
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• 2005

드라마와 같은 비디오에서 사람의 얼굴은 일반적으로 자주 등장하며 비디오 내용을 분석하기 위한 유용한 정보를 제공한다. 얼굴검출은 얼굴인식 및 얼굴영상의 DB 관리와 같은 응용분야에 중요한 역할을 한다. 본 논문에서는 비디오 등장인물 검색을 위한 얼굴검출 기법을 제안하였다. 전체 과정은 크게 세단계로 구성되며 첫 번째 장면전환 검출단계, 두 번째 얼굴영역 검출단계, 마지막으로 얼굴의 특징점인 눈과 입 검출단계로 구성되며, 색상에 기반한 얼굴영역 검출단계에서 발생된 얼굴 특징점을 눈과 입의 검출에 적용하였다. 실험결과 다양한 환경에서 성공적으로 얼굴을 검출하며, 기존의 색상기반 얼굴검출 방법에 비해 측면영상에서 $24\%$의 성능향상을 보였다.

• 대한의용생체공학회:의공학회지
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• 제18권1호
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• pp.17-24
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• 1997

We have developed a patient monitoring system including module-based bedside monitors, interbed network, central stations, clinical workstations, and DB servers. A bedside monitor with a color LCD can accommodate up to 3 module cases and 21 different modules. Six different physiological parameters of ECG, respiration, invasive blood pressure, noninvasive blood pressure, body temperature, and arterial pulse oximetry with plethysmoyaph are provided as parameter modules. In a single bedside monitor, modules and a module controller communicate with IMbps data rate through an intrabed network based on RS-485 and HDU protocol. At the same time, it communicates with other bedside monitors and central stations through interbed network based on 1 OMbps Ethernet and TCP/IP protocol. Central stations using 20" color CRT monitors can be connected with many bedside monitors and they display 18 channels of waveforms simultaneously. Clinical workstations are used mainly for the review of patient datE In order to accommodate more advanced data management capabilities such as 24-hour full disclosure, we have developed a relational database server dedicated to the patient monitoring system. Software for bedside monitor, central station, and clinical workstation fully utilizes graphical user interface techniques and all functions are controlled by a rotate/push button on the bedside monitor arid a mouse on the central station and clinical workstation. The entire system satisfies the requirements of AAMI and ANSI standards in terms of electrical safety and performances.nces.

• International Journal of Concrete Structures and Materials
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• 제7권4호
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• pp.319-332
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• 2013

The purpose of this study was to investigate the design comparison of totally prefabricated bridge substructure system. Prefabricated bridge substructure systems are a relatively new and versatile alternative in substructure design that can offer numerous benefits. The system can reduce the work load at a construction site and can result in shorter construction periods. The prefabricated bridge substructures are designed by the methods of Korea Highway Bridge Code (KHBD) and load and resistance factor design (AASHTO-LRFD). For the design, the KHBD with DB-24 and DL-24 live loads is used. This study evaluates the design method of KHBD (2005) and AASHTO-LRFD (2007) for totally prefabricated bridge substructure systems. The computer program, reinforced concrete analysis in higher evaluation system technology was used for the analysis of reinforced concrete structures. A bonded tendon element is used based on the finite element method, and can represent the interaction between the tendon and concrete of a prestressed concrete member. A joint element is used in order to predict the inelastic behaviors of segmental joints. This study documents the design comparison of totally prefabricated bridge substructure and presents conclusions and design recommendations based on the analytical findings.

• 한국컴퓨터정보학회논문지
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• 제24권3호
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• pp.77-86
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• 2019

The advent of Internet of Things (IoT) makes common nowadays computing environments involving programming not a single computer but several heterogeneous distributed computers together. Developing programs separately, one for each computer, increases programmer burden and testing all the programs become more complex. To address the challenge, this paper proposes an RPC-based unified programming language, UniPy, for development of MGC (eMbedded, Gateway, and Cloud) applications in IoT systems configured with popular computers such as Arduino, Raspberry Pi, and Web-based DB server. UniPy offers programmers a view of classes as locations and a very simple form of remote procedure call mechanism. Our UniPy compiler automatically splits a UniPy program into small pieces of the program at different locations supporting the necessary RPC mechanism. An advantage of UniPy programs is to permit programmers to write local codes the same as for a single computer requiring no extra knowledge due to having unified programming models, which is very different from the existing research works such as Fabryq and Ravel. Also, the structure of UniPy programs allows programmers to test them by directly executing them before splitting, which is a feature that has never been emphasized yet.

• 한국지하수토양환경학회지:지하수토양환경
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• 제24권2호
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• pp.8-22
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• 2019

Among numerous chemicals used globally, the number of emerging contaminants is increasing. Numerical modeling for contaminant fate and transport in the subsurface is critical to evaluate environmental and health risk. In general, such models require physicochemical properties of contaminants as input values, which can be found in numerous chemical databases (DB). However, there exist lack of information specific to recently emerging contaminants, which requires estimation of physicochemical properties using regression programs. The purpose of the study is to introduce the workflow for identifying physicochemical properties of potential contaminants utilizing numerous chemical DBs, which frequently lists up potential contaminants for estimating chemical behavior. In this review paper, details of several chemical DBs such as KISChem, TOXNET, etc. and regression programs including EPI $Suite^{TM}$, ChemAxon, etc. were summarized and also benefit of using such DBs were explained. Finally, a few examples were introduced to estimate predominant phase, removal ratio, partitioning, and eco-toxicities by searching or regressing physicochemical properties.

• 한국컴퓨터정보학회논문지
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• 제24권4호
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• pp.123-128
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• 2019

In modern society, there are WEB sites that provides information in various fields by many advances in IT technology. As the number of users accessing the Web increases, one server becomes unavailable, and multiple servers are deployed to provide the service. In addition, systems that control servers are required to manage multiple servers. However, server control systems in the existing market are mostly those that notify managers through SMS and apps when a server's down or a controlled port is closed. However, in case of servers that generate a lot of traffic, the Web server and the WAS are operated and managed each independently. The WEB and WAS provide service by connecting to each other. However, the connection between WEB and WAS may be disconnected due to various environmental factors. In this case, the existing control system can not determine whether the service is working properly. Even in the case of WEB and WAS of a server that is operated independently, there is a phenomenon that the existing control system does not know the problem even when the normal service is not provided due to environmental factors such as disconnection to DB. In this paper, we implemented a system to check the normal state of Web service using Web crawling to solve this problem.

• Asia pacific journal of information systems
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• 제32권4호
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• pp.830-856
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• 2022

The Digital Government landscape is changing to reflect how governments try to discover innovative digital solutions, and how they transform themselves in the process. In addition, with the advent of information and communication technology (ICT), e-governance became an essential part of the government. Among the services provided by the Korean government, the Minwon24 online portal is the most used one. However, it has some processing limitations, namely: (1) it provides a cumbersome document authenticity service; (2) people cannot know what happened even if the agency handles the documents arbitrarily. To address the issues outlined above, blockchain processing can be a good alternative. It has a tremendous potential in that it has maximum transparency and a low risk of being hacked. Resource management is one of the areas where blockchain is frequently used. The present study suggests a new model based on blockchain for Minwon24; the proposed model is a type of resource management. There are three participants: issuer, owner and receiver. The proposed model has two stages: issuing and exchanging. Issuing is creating civil documents on the database, which is BigchainDB in this study. Exchanging, the next stage, is a transaction between the owner and the receiver. Based on this model, the actual program is built with the programming language Python. To evaluate the model, the study uses various criteria and it shows the excellence of the model in comparison to others in prior research.

• 대한토목학회논문집
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• 제30권2A호
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• pp.137-148
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• 2010

본 연구에서는 기존 엑스트라도즈드교와 PSC 사장교 사이의 영역인 주탑고비 1/6~1/7의 고주탑을 적용하여 엑스트라도즈드교의 구조적, 경제적 특성을 평가하였다. 주탑고가 증가함에 따라 사재의 연직하중 분담율의 증가와 함께 변동응력도 증가하여 사재의 피로안정성이 주요 설계변수임을 알 수 있었다. 국내에서는 엑스트라도즈드교의 설계기준 부재로 인하여 일본 설계기준을 준용하고 있다. 또한, 피로 검토하중도 정립되지 않고 있어 본 연구에서는 일본 피로 검토하중에 대응하는 국내 활하중을 적용 검토하여 DL24 하중이 피로 검토하중으로 적정함을 알 수 있었다. 제시된 피로 검토하중을 적용하여 주탑고, 주거더의 강성, 케이블 면수 등을 매개변수로 엑스트라도즈드교의 구조적, 경제적 특성을 검토하였다. 본 연구의 결과로써 일면 케이블 배치가 이면 케이블 배치보다 경제적임을 알 수 있었다. 또한, 주탑고비가 1/6의 변단면 고주탑 엑스트라도즈교에서 연직 하중분담율이 30~50% 이내로 모든 사재가 허용변동응력 이내로 들어와 사재를 효율적으로 사용할 수 있어 가장 경제적임을 알 수 있었다. 본 연구를 통해 기존의 엑스트라도즈드교보다 높은 주탑고를 적용함에 따라 구조적, 경제적으로 효율성을 높일 수 있음을 확인하였다.