• Journal of Bio-Environment Control
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• v.26 no.4
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• pp.242-248
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• 2017

This study was conducted to develop a cylindrical paperpot manufacturing equipment which is capable of continuously producing paperpots with a constant size. The equipment consists of the soil supply part, the paper supply part, the pot manufacturing part, the paperpot cutting part and its process for manufacturing paperpot from the soil supply to the paperpot cutting is continuously performed. As a result of the performance test using this equipment, we suggest that the optimal moisture content and injection pressure to supply soil are 50%~60%, and 0.5 Mpa respectively. Moreover the appropriate temperature for adhesive strength is $150{\sim}160^{\circ}C$ taking into account the performance of device and adhesion time. Also, considering the cutting speed and safety, it is appropriate to adopt a straight blade having a clean plan at a minimum angle of $30^{\circ}$. In addition, the manufacturing capacity of the developed equipment was 3300 pots per hour.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.40 no.7
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• pp.417-427
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• 2016

This paper is the first investigation of the steady flow characteristics of an SI engine with a semi-wedge combustion chamber as a function of the port shape. For this purpose, the planar velocity profiles were measured at the 1.75B position by particle image velocimetry. The flow patterns were examined with both a straight and a helical port. Two swirls were observed up to 4 mm valve lift with the straight port and up to 2 mm with the helical one; however, only one swirl was present after these lifts. The flow characteristics changed suddenly between 4 and 5 mm lift in the straight port; on the other hand, the change with lift was gradual with the helical port - the transition points between flow regimes were different with the port shapes. In addition, the centers of the swirls were relatively far from the cylinder center so that the effect of eccentricity may not be negligible at 1.75B, regardless the shape. The eccentricity values with the straight port were especially high - over 0.5 for all lifts. Finally, real velocities were found to be much lower than those predicted by the assumption of ISM evaluation, with the profiles differing qualitatively as well.

• Korean Journal of Heritage: History & Science
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• v.46 no.3
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• pp.68-77
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• 2013

This report is based on the investigation of potholes which are formed by fluvial erosion. A pothole is called so because it is a hole that looks like a coffeepot. The results of previous studies are applied to the 'Jakgwaecheon Porthole' of this study. The study is focused on the dimension and morphology of the Pothole and investigates the effects of stream sediments, river flow, geological structural lines, etc. on the formation of potholes. As a result of measuring 61 potholes in this area, we recognized that the elliptical dish-shaped cross sections are dominant and inferred that their longitudinal direction on the plain is affected by the direction of the stream flow. Also, 'Jakgwaecheon Pothole' is very characterized in terms of scale and morphology. Furthermore, it is harmonious with the beautiful landscape, humanity, and historical values and it can be suggested that it is qualified to be registered as a geoheritage structure.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.1
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• pp.214-220
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• 2008

This study aims to design a digital portfolio assessment system in ubiquitous computing(DPASUbi). To achieve that goal, the following issues were worked: Review of various theoretical discussions on portfolio and an analysis of existing programs to select elements to be included in the DPASUbi. Educational evaluation scenarios for the DPASUbi were developed based on the elements. The system was designed on reflecting these elements, that is, learning activities, assessment and usage of portfolio, ubiquitous technology and database. This system will provide guidance on what methods and assessment procedures should be applied in the ubiquitous computing environment totally different from the conventional one. Also, The new system will be helpful in indicating what kind of techniques should be required in the real educational evaluation.

• Journal of KIISE:Information Networking
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• v.28 no.1
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• pp.93-101
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• 2001

멀티캐스트 응용을 다루는 기존의 많은 네트워킹 솔루션들은 특정한 트랜스포트 기술에 기반을 두고 있기 때문에 인터넷, ATM과 같은 하부 트랜스포트 네트워크에 따라 서로 다른 접근 방법을 필요로 한다. 본 논문에서는 여러트랜스포트 네트워크에 적용 가능한 새로운 멀티캐스트 서비스 구조(MSA: Multicast Service Architecture)를 제안한다. MSA는 기존의 트랜스포트 네트워크 프로토콜들이 연결제어를 위하여 그대로 사용될수 있도록 설계되어 최소한의 변경으로 기존 트랜스포트 네트워크 상에서 운용될 수 있다. MSA는 트랜스포트 네트워크에 독립적으로 다양한 멀티미디어 멀티캐스트 응용들을 수용할 수 있으며 망 중심의 통신관리체계를 규정한다. MSA는 여러 가지 개념들을 도입하여 유연하고 확장성 있는 통신관리를 지원하는데 특히 호/연결제어 기능을 단말로부터 분리하여 정의함으로써 원격제어와 제어의 이동성을 지원할 수 있다. 따라서 사용자는 보다 다양한 방법으로 멀티미디어 멀티캐스트 서비스를 이용할 수있게된다. 또한 단말관리자와 가상 디바이스 개념을 도입하여 응용 개발자가 트랜스포트 네트워크나 물리적 디바이스의 상세한 특성을 모르더라도 응용을 설계할 수 있도록하였다. MSA를 구성하는 여러개의 서비스 컴포넌트들은 미들웨어 상에서 동작한다. 우리는 시뮬레이션을 통하여 MSA를 분석하였다.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.41 no.10
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• pp.23-29
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• 2004

In this paper, the asynchronous quasi dual-port SRAM employing a single port structure in SRAM embedded SOC (System On Chip) is proposed. External host can access the internal SRAM freely and the data on internal SRAM can be transferred to an another external circuitry without a synchronous signal of an external host, which operates as an asynchronous dual-port SRRAH The performances of the proposed circuits and control structure are verified through the simulation and we fabricated it using a 0.35um CMOS technology. As the results, the chip shows reduced area about 20% and saved power also 20% than conventional architectures.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2011.10a
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• pp.95-97
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• 2011

The portfolios of students are archives where the studies of the students are recorded during the dates attended and very important data for the employment and the self-management. In the past, the portfolios are written on the papers and managed. However, the papers are easy to be lost and damaged. In this paper, we propose the design of portfolio framework to store and manage the data of portfolio efficiently. The proposed framework is capable of storing and managing students's portfolios using wired or wireless networks. The industries and professors are also easy to search appropriate talented students according to the requirements using the proposed framework.

• Proceedings of the Korean Information Science Society Conference
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• 2007.06b
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• pp.412-417
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• 2007

멀티 포트 네트워크 인터페이스 카드는 지원 가능한 대역폭의 합이 포트의 수에 따라서 결정된다. 따라서 I/O 버스와의 대역폭 균형을 맞출 수 있는 장점이 있다. 또한 상대적으로 저렴한 스위치 가격으로 높은 대역폭을 지원해 줄 수 있다. 이러한 이유에서 최근 멀티 포트 네트워크 인터페이스 카드는 고 가용성 서버뿐만 아니라 고성능 서버에서도 사용되기 시작하고 있다. 본 논문에서는 이러한 멀티 포트 네트워크 인터페이스 카드가 지원할 수 있는 최대 대역폭을 분석한다. 특히 최근에 등장한 멀티 코어 프로세서 서버에서 TCP/IP 성능 측정을 수행하여 멀티 코어 자원을 최대한 활용하는지를 분석한다. 분석 결과 현재 리눅스가 제공하는 인터럽트 분산 정책 및 패킷 처리 기법으로는 멀티 포트 네트워크 인터페이스 카드의 높은 대역폭 특성을 최대한 활용하기에는 부족함을 밝힌다. 또한 각 포트 별로 들어오는 네트워크 흐름의 특성이 서로 다를 때에 시스템이 그에 신속히 적응하지 못함을 측정 결과를 통해서 보인다. 이러한 측정 및 분석 결과는 멀티 코어 시스템에서 멀티 포트 NIC을 최대한 활용하기 위한 리눅스의 향상 필요성을 시사하며 그를 위한 방안을 제시할 수 있다.

• Journal of Digital Contents Society
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• v.14 no.4
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• pp.545-555
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• 2013

Recently student portfolio is widely used as an evaluation method for self-directed performance in engineering education of the university. Especially, as many of the Innovation Centers for Engineering Education and ABEEK held student portfolio competitions, a lot of students in engineering college participate in student portfolio includes the contents and careers of the entire process of university. However, except for courses related to capstone design, there are few regular courses applied to Learning Portfolio in engineering education. Through using Learning Portfolio in courses, students take opportunities of organized collection of learning contents and critical reflection. Under these background study, the regular course in engineering education is may be appropriate for using Learing Portfolio in lecture. In this paper, we present the case study for the Data Structure course opened in the first semester of 2013 which is organized as a Learning Portfolio. According to the results of applying Learning Portfolio to the regular course, it turns out that learners can develope self-directed learning ability in exploring the learning process, and manage a learning process systematically through self-reflection in learning process.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.37 no.3
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• pp.603-610
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• 2017

Various type of pavement deterioration such as crack, bumpy, pothole is rapidly increasing according to the accelerated environmental changes like heavy rainfall, frequent snowing, difference temperature, etc. Accident related to pothole that cause fatal traffic accidents has been increased more than five times over the next five years starting from 2008. As direct or indirect damage by pothole which caused injuries and car damages increases every year, quicker and more efficient management measures are necessary. This study presents the algorithm for materials quantity take-off. The algorithm was suggested by correlation in pothole size and area. Suggested algorithm were confirmed the validity through the 15 field survey in capital area. According to the results of survey, usually the residual materials at which 5~7 kg was generated decreased to 1~2 kg. It showed that automatic pothole detection system is expected not only to reduce materials and resources, but also to contribute to quality improvements of pavement through more accurate material take-off from the situation of constructing rely on their own judgement.