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The differences in a perception of Housing unit between male and female high school students (가정교과를 이수한 남.여고등학생의 주생활 단원에 대한 인식 차이)

  • 신용해;조재순
    • Journal of Korean Home Economics Education Association
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    • v.11 no.1
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    • pp.47-57
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    • 1999
  • The purpose of this study was to investigate the differences in the perception of housing unit between female and male among high school students who learned Home Economics in high school. The number of 200 samples were analyzed with frequencies, percentages, t-test, regression and $$\chi$^2$ analyses using SPSS/Win. The results showed that there were no sextual differences in general perceptions of Housing unit such as importance, usefulness, and satisfaction with the unit. The most demanded housing contents as the principle of interior design, and the least as the history of housing. There were sexual differences in only a few cotents. However, all of 29 items were demanded over median point of 3.0. Most students ofen imagined their own dream houses and thought about the way to improve their own rooms. They were least concentrated on the newspaper articles on housing. They were sexual differences in the level of practice the Housing contents learned in the class. These results should be considered in the 7th curricumn male students must take Home Economics.

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Performance Evaluation of On-Demand Routing Protocol using Look-ahead Selective Flooding in Ad-hoc Network (Ad-hoc 네트워크에서 Look-ahead Selective Flooding을 이용한 On-Demand 라우팅 프로토콜 성능 개선)

  • Yo-chan Ahn
    • Journal of Information Technology Applications and Management
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    • v.10 no.2
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    • pp.61-71
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    • 2003
  • Ad-hoc networks are characterized by multi-hop wireless links, frequently changing network topology and the need for efficient dynamic routing protocols. In an Ad-hoc network, each host assumes the role of a router and relays packets toward final destinations Because a packet is broadcast to all neighboring nodes, the optimality criteria of wireless network routing is different from that of wired network routing. tn this paper 1 point out the more important cost factor than the number of links in the Ad-hoc network. A class routing protocols called on-demand protocols has recently found attention because of their low routing overhead since it performs a blind flooding to look for a path. In this paper, 1 propose the method which reduces overhead by using the information of neighboring nodes and doing a selective flooding. Simulation results demonstrate better reduction of routing overheads with this scheme.

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A study on the multicasting algorithm for radix-2 tree ATM switch (Radix-2 트리 ATM 스위치를 위한 멀티캐스팅 알고리즘에 관한 연구)

  • 김홍열;임제택
    • Journal of the Korean Institute of Telematics and Electronics S
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    • v.34S no.1
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    • pp.1-8
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    • 1997
  • A wide class of networking application services, such as video teleconferencing, VOD, LAN bridging, and distributed data processing require multipoint communications. The essential component inteh network to achieve this is a multicast packet switch which is capable of packet replication and switching. In this paper, we propose an efficient mukticast addressing scheme using the smallest number of routing bits which is deterministic lower bound. The new scheme performs all point-to-multipoint connection in radix-2 tree ATM switch like banyan network. Also, we provide a simple radix-2 switch block diagram for achieving our algorithm. And we investigate several addressing schemes for implementing multicasting in radix-r tree ATM switch and evaluate several performance factors, such as complexity of the additional header bits, requirement of the internal speedup and complexity of the major hardware.

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Performance Prediction of a Gas Turbine Using CO2 as Working Fluid (CO2를 작동유체로 하는 가스터빈의 성능예측)

  • Yang, Hyun-Jun;Kang, Do-Won;Lee, Jong-Jun;Kim, Tong-Seop
    • The KSFM Journal of Fluid Machinery
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    • v.14 no.2
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    • pp.41-46
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    • 2011
  • This study investigated the changes in performance and operating characteristics of an F-class gas turbine according to the change of working fluid from air to carbon dioxide. The revised gas turbine is the topping cycle of the semi-closed oxy-fuel combustion combined cycle. With the same turbine inlet temperature, the $CO_2$ gas turbine is expected to produce about 85% more power. The main contributor is the greater compressor mass flow and the added oxygen flow for the combustion. Compressor pressure ratio increases about 50%. However, the gas turbine efficiency reduces about 10 %. Modulation of inlet guide vane to reduce the compressor inlet mass flow, the major purpose of which is to reduce the compressor inlet Mach number, was also performed.

Adaptive Q-Algorithm for Multiple Tag Identification in EPCglobal Gen-2 RFID System

  • Lim, In-Taek
    • Journal of information and communication convergence engineering
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    • v.8 no.3
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    • pp.307-311
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    • 2010
  • EPCglobal Class-1 Gen-2 protocol has been proposed for UHF-band RFID systems. In Gen-2 standard, Q-algorithm was proposed to select a frame size for the next query round without estimating the number of tags. Therefore, the Q-algorithm has advantage that the reader's algorithm is simpler than other algorithms. However, it is impossible to allocate the optimized frame size. Also, the original Q-algorithm did not define an optimized parameter C for adjusting the frame size. In this paper, we propose an adaptive Q-algorithm with the different parameter $C_c$ and $C_i$ in accordance with the status of reply slot. Simulation results show that the proposed adaptive Q-algorithm outperforms the original Gen-2 Q-algorithm.

Analysis on the Architectural Characteristics of Super High Rise Apartments (초고층 공동주택의 건축적 특성 분석)

  • Park, Hyeon-Ku;Song, Hyuk;Go, Seong-Seok
    • Journal of the Korean housing association
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    • v.18 no.1
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    • pp.11-18
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    • 2007
  • At the economical crisis of Korea in 1997, self-determined price for apartment and the revision increasing the ratio of residential area for mixed-use residential building were introduced to activate the construction industry, which causes construction companies to build super high rise apartment discriminative and high class orientated. This study aims to classify the super high rise building which is planned to build or built recently and to analyze the architectural characteristics. The objects are 288 unit households in 26 apartment complexes higher than twenty five story since 1998. As a result, super high rise building comparing with existing apartments were being varied in plan types of main building and unit household and in construction types. As for the plan, the number of walls having opening to outdoor were increased and it is considered that high rise building can take advantage of a view, lighting and sunshine. The location of living room that used to be in the center of unit in existing apartment was moved freely without rule.

Analysis of Dynamic bandwidth allocation scheme for ATM/LAN interworking unit (ATM/LAN 연동장치의 동적대역할당 방식에 대한 성능해석)

  • 이은준;우상철;윤종호
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.21 no.12
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    • pp.3132-3143
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    • 1996
  • In the evaluation of Broadband-ISDN, the main issue is to interconnect existing LANs and MANs to B-ISDN based on Asynchrous Transfer Mode. However, LANs provide connectionless services, whereas the ATM network provides connection-oriented services. So some problem arises from accessing ATM switchs to transparently transmit connectionless data via B-ISDN. Two methods then were recommended by ITU-TS to support the connectionaless services. In the paper, we do the numerical analysis, using the stochastic fluid flow method, of dynamic bandwidth allocation sheme with two class traffics in the virtual path established between Interworking Units(JWUS) interconnecting LANs to an ATM network and Connectionless Servers(CLSs). The loss mechanism of each traffic is controlled by the contents of buffer. The vandwidth which the IWU requests the CLS is estimated by the number of On-Off sources in the On state. We use the stochsastic fluide flow method which is to find the steady-state joint probability in each level of the IWU buffer. The length of the IWU buffer as the real random variable is changed by traffics entering the IWU.

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A Study on the Reference Template Database Design Method for Frame-based Classification of Underwater Transient Signals (프레임 기반의 수중 천이신호 식별을 위한 기준패턴의 데이터베이스 구성 방법에 관한 연구)

  • Lim, Tae-Gyun;Ryu, Jong-Youb;Kim, Tae-Hwan;Bae, Keun-Sung
    • Proceedings of the IEEK Conference
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    • 2008.06a
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    • pp.885-886
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    • 2008
  • This paper presents a reference template design method for frame-based classification of underwater transient signals. In the proposed method, framebased feature vectors of each reference signal are clustered by using LBG clustering algorithm to reduce the number of feature vectors in each class. Experimental results have shown that drastic reduction of the reference database can be achieved while maintaining the classification performance with LBG clustering algorithm.

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Performance Test of MGT Combined Heat & Power System (마이크로 가스터빈 열병합 발전시스템 성능평가)

  • Hur, Kwang-Beom;Park, Jung-Keuk;Rhim, Sang-Kyu
    • 유체기계공업학회:학술대회논문집
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    • 2006.08a
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    • pp.313-316
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    • 2006
  • As Decentralized Generation(DG) becomes more reliable and economically feasible, it is expected that a higher application of DG units would be interconnected to the existing grids. This new market penetration of DG technologies is linked to a large number of factors like technologies costs and performances, interconnection issues, safety, market regulations, environmental issues or grid connection constrains. Korea Electric Power Corporation (KEPCO) has researched performance characteristics of the 60k W class 1) basic start-up & shutdown operation analysis 2) interconnection test 3) MGT -absorption chiller-heater system in the local condition. Variations of heat recovery from exhaust gas has measured according to micro gas turbine output of 15, 30, 45, 60kW. From those results, the performance of the MGT-absorption chiller/heater system has been evaluated. The suggested strategy and experience for the evaluation of the distributed generation will be used for the introduction of other distributed generation technologies into the grid in the future.

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The Construction of Universal Mulitple Processing Unit based on De Bruijn Graph

  • Park, Chun-Myoung;Song, Hong-Bok
    • Proceedings of the IEEK Conference
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    • 2002.07b
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    • pp.959-962
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    • 2002
  • This paper presents a method of constructing the universal multiple processing element unit(UMPEU) based on De Bruijn Graph. The proposed method is as following. Firstly we propose transformation operators in order to construct the De Bruijn graph using properties of graph. Secondly we construct the transformation table of De Bruijn graph using above transformation operators. Finally we construct the De Bruijn graph using transformation table. The proposed UMPEU is capable of constructing the De Bruijn geraph for any prime number and integer value of finite fields. Also the UMPEU is applied to fault-tolerant computing system, pipeline class, parallel processing network, switching function and its circuits.

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