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Fauna of Macroinvertebrates and Composition of Functional Feeding Groups about the Aquatic Insects to Microhabitats from the Geum River, Korea

  • Park, Young-Jun;Cho, Young-Ho;Han, Yong-Gu;Oh, Hong-Sik;Kwon, Oh-Seok;Nam, Sang-Ho
    • Journal of Ecology and Environment
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    • v.29 no.5
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    • pp.415-424
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    • 2006
  • The main objective of this study is to find out the fauna of macroinvertebrate and composition of functional feeding groups about the aquatic insects to microhabitat from the Geum River, Korea. This study is based on investigations of the main channel of Geum River, Korea which is upstream of Daecheong Dam, and carried out in the spring and autumn of 2004. Collections from all the sites were 39,532 individuals, 130 species, 54 families, 16 orders, 7 classes, and 4 phyla of macroinvertebrates. Aquatic insects were composed of 90.76% (118 species) and 98.88% (39,088 individuals) of all the identified species. Among the microhabitats, the riffles were collected 26,293 individuals and 92 species, and the runs were collected 12,329 individuals and 89 species. Finally, the pools were collected 494 individuals and 41 species. In this survey, the proportions of functional feeding groups of aquatic insects were as follows (percent of identified): predators 37.65%, gathering-collectors 23.53%, scrapers 16.47%, filtering-collectors 11.76%, shredders 9.41% and plant-piercers 1.18%. Also, the functional feeding groups were sorted according to microhabitat, in the riffles 30.65% were predators and 29.03% were gathering-collectors; in the run 30.3% were predators, and 28.79% were gathering-collectors; while in the pools 36.67% were predators, and 30.0% were gathering-collectors. In all microhabitats, gathering collectors and predators were predominant, because most of the survey sites are in the midstream. Also, the scrapers were shown more frequently in the riffle (17.74%) and run (18.18 %) than pool (13.13%), the filtering-collectors were shown more frequently in the riffle (14.52%) and the run (12.12%) than the pool (6.67%), and the plant-piercers (3.33%) were found only in pools. But the shredders weren't a difference in the run (10.61%), the pool (10.0%) and the riffle (8.06%), because of the characteristic. Microhabitats (riffle and run) are much alike in composition ratio of functional feeding groups and pool was very lower out of composition ratio in microhabitats. But riffle is very important than run, because most of individual occur in streams. Besides, pool was diverse to composition ratios, considering the number of individuals.

Performance Analysis of a Multi-Carrier DS-CDMA/BPSK Signal with Hybrid SC/MRC-$L_{c}/L$ Diversity Reception in Multipate Fading Channe (다중경로 페이딩 채널에서 하이브리드 SC/MRC-$L_{c}/L$ 다이버시티 수신 Multi-Carrier DS-CDMA /BPSK 신호의 성능 해석)

  • 김영철;조성준
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.12 no.4
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    • pp.630-643
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    • 2001
  • In this paper, the performance of a Multi-Carrier DS-CDMA system with Hybrid $SC/MRC- L_{c}/L$ diversity in the multipath Rayleigh fading environment is analyzed and compared with that of a Wideband DS-CDMA system. Each carriers of the number of the input diversity branches in the Multi-Carrier DS-CDMA system is L and among L, the branches of $L_c$ are chosen to be maximum-ratio-combined. And the diversity outputs are coherent-detected and despread by the correlator of each carrier. As the result, we have known that the structure of the Wideband DS-CDMA system with Hybrid $SC/MRC-L_{c}/L$ diversity reception becomes simple due to no synchronization of bit or phase and in terms of the error performance, the performance of Hybrid $SC/MRC- L_{c}/L$ diversity is better than that of selection diversity, but worse than that of MRC diversity. Moreover, the performance of a Multi-Carrier DS-CDMA system is better than that of a Wideband DS-CDMA system in multipath Rayleigh fading channel since Hybrid $SC/MRC- L_c/L$ diversity can obtain gain from each diversity branch. In case four carriers are used and required BER is $10^{-6}$ in wireless data communication, Hybrid SC/MRC-2/4 diversity can increase more 17 users than Hybrid SC/MRC-2/3 diversity because the better input branches can be selected through increase of input branches.

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Bit-serial Discrete Wavelet Transform Filter Design (비트 시리얼 이산 웨이블렛 변환 필터 설계)

  • Park Tae geun;Kim Ju young;Noh Jun rye
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.4A
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    • pp.336-344
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    • 2005
  • Discrete Wavelet Transform(DWT) is the oncoming generation of compression technique that has been selected for MPEG4 and JEPG2000, because it has no blocking effects and efficiently determines frequency property of temporary time. In this paper, we propose an efficient bit-serial architecture for the low-power and low-complexity DWT filter, employing two-channel QMF(Qudracture Mirror Filter) PR(Perfect Reconstruction) lattice filter. The filter consists of four lattices(filter length=8) and we determine the quantization bit for the coefficients by the fixed-length PSNR(peak-signal-to-noise ratio) analysis and propose the architecture of the bit-serial multiplier with the fixed coefficient. The CSD encoding for the coefficients is adopted to minimize the number of non-zero bits, thus reduces the hardware complexity. The proposed folded 1D DWT architecture processes the other resolution levels during idle periods by decimations and its efficient scheduling is proposed. The proposed architecture requires only flip-flops and full-adders. The proposed architecture has been designed and verified by VerilogHDL and synthesized by Synopsys Design Compiler with a Hynix 0.35$\mu$m STD cell library. The maximum operating frequency is 200MHz and the throughput is 175Mbps with 16 clock latencies.

Efficient Multiplex Audio Monitoring System in Digital Broadcasting (디지털 방송에서 효율적인 다중 오디오 모니터링 시스템)

  • Kim, Yoo-Won;Sohn, Surg-Won;Jo, Geun-Sik
    • Journal of the Korea Society of Computer and Information
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    • v.13 no.7
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    • pp.91-98
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    • 2008
  • In digital broadcasting, it is possible to multiplex maximum one hundred audio or music programs into MPEG-2 transport stream, which is suitable for transmitting through one channel. In order to check if multiplex music programs are transmitted well, we need a multiplex audio monitoring system that monitors the programs in real-time. In analog broadcasting, we have used hardware-based audio monitoring system for a small number music programs. However, the effectiveness of hardware-based audio monitoring system from the cost and function viewpoint is so low that a new system is needed for digital broadcasting. In this paper, we have designed and implemented a software-based audio monitoring system to satisfy these requirements. In this implementation, only one PC is used without other hardware facilities, and the system monitors digital broadcasting music programs effectively. Transmitted digital broadcasting streams are demultiplexed into many music programs and the realtime value of audio level and packet error information for these programs are displayed in the screen. Thus, the system detects and shows the abnormal transmitting programs automatically. Simulation results show that effective realtime multiplex audio monitoring is possible for digital broadcasting music programs.

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Industrial Fluctuations and Locality of Busan with Records (기록으로 본 부산의 산업변동과 로컬리티)

  • Song, Jung-Sook
    • Journal of Korean Society of Archives and Records Management
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    • v.16 no.2
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    • pp.143-172
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    • 2016
  • This study analyzes the process of growth of Busan from a fishing village to the capital city of South Gyeongsang Province and the central city of transportation and commerce, and an industry with records. The results of the analysis are as follows: after the port opened in 1876, there has been a decline in settlement spaces in Dongnae; on the other hand, there has been an increase in migration spaces around the port of Busan. Waegwan (倭館) nearby Yongdusan Mountain (龍頭山) was changed to the Japanese concession; thus, the number of Japanese moving into Busan had rapidly increased. As a result, the Japanese government carried out reclamation work for securing available lands for the construction of port facilities and other facilities. The Japanese government built public offices and houses, as well as production facilities for daily necessities around the port of Busan. The opening of the Seoul Busan railway (京釜線) and the cross-channel liner between Busan and Shimonoseki (釜關連絡船) led to the growth of Busan and the development of its status. At this time, as the main industry of Busan was trade, Busan had grown as a commercial city. As Busan had grown as a central city of transportation and commerce, the provincial government building of Gyeongsangnam-do (慶尙南道) moved to Busan. Thus, Busan became the central city of local politics and administration. After the Land Survey Project, a large scale of farmers were recruited for low-wage work in the new port. Because of the abolition of the corporation law, Japanese capitalists moved into their colony in Busan. There, large-scale factories, such as the Joseon cotton textile factory, were established. Through this process, the locality of Busan was changed from a fishing village to a commercial city and, finally, to a city of commerce and industry.

Password-Based Authentication Protocol for Remote Access using Public Key Cryptography (공개키 암호 기법을 이용한 패스워드 기반의 원거리 사용자 인증 프로토콜)

  • 최은정;김찬오;송주석
    • Journal of KIISE:Information Networking
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    • v.30 no.1
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    • pp.75-81
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    • 2003
  • User authentication, including confidentiality, integrity over untrusted networks, is an important part of security for systems that allow remote access. Using human-memorable Password for remote user authentication is not easy due to the low entropy of the password, which constrained by the memory of the user. This paper presents a new password authentication and key agreement protocol suitable for authenticating users and exchanging keys over an insecure channel. The new protocol resists the dictionary attack and offers perfect forward secrecy, which means that revealing the password to an attacher does not help him obtain the session keys of past sessions against future compromises. Additionally user passwords are stored in a form that is not plaintext-equivalent to the password itself, so an attacker who captures the password database cannot use it directly to compromise security and gain immediate access to the server. It does not have to resort to a PKI or trusted third party such as a key server or arbitrator So no keys and certificates stored on the users computer. Further desirable properties are to minimize setup time by keeping the number of flows and the computation time. This is very useful in application which secure password authentication is required such as home banking through web, SSL, SET, IPSEC, telnet, ftp, and user mobile situation.

Classification of Ground Subsidence Factors for Prediction of Ground Subsidence Risk (GSR) (굴착공사 중 지반함몰 위험예측을 위한 지반함몰인자 분류)

  • Park, Jin Young;Jang, Eugene;Kim, Hak Joon;Ihm, Myeong Hyeok
    • The Journal of Engineering Geology
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    • v.27 no.2
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    • pp.153-164
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    • 2017
  • The geological factors for causing ground subsidence are very diverse. It can be affected by any geological or extrinsic influences, and even within the same geological factor, the soil depression impact factor can be determined by different physical properties. As a result of reviewing a large number of papers and case histories, it can be seen that there are seven categories of ground subsidence factors. The depth and thickness of the overburden can affect the subsidence depending on the existence of the cavity, whereas the depth and orientation of the boundary between soil and rock are dominant factors in the ground composed of soil and rock. In case of soil layers, more various influencing factors exist such as type of soil, shear strength, relative density and degree of compaction, dry unit weight, water content, and liquid limit. The type of rock, distance from the main fracture and RQD can be influential factors in the bedrock. When approaching from the hydrogeological point of view, the rainfall intensity, the distance and the depth from the main channel, the coefficient of permeability and fluctuation of ground water level can influence to ground subsidence. It is also possible that the ground subsidence can be affected by external factors such as the depth of excavation and distance from the earth retaining wall, groundwater treatment methods at excavation work, and existence of artificial facilities such as sewer pipes. It is estimated that to evaluate the ground subsidence factor during the construction of underground structures in urban areas will be essential. It is expected that ground subsidence factors examined in this study will contribute for the reliable evaluation of the ground subsidence risk.

Development of a Real-time OS Based Control System for Laparoscopic Surgery Robot (복강경 수술로봇을 위한 실시간 운영체제 기반 제어 시스템의 개발)

  • Song, Seung-Joon;Park, Jun-Woo;Shin, Jung-Wook;Kim, Yun-Ho;Lee, Duk-Hee;Jo, Yung-Ho;Choi, Jae-Seoon;Sun, Kyung
    • Journal of Biomedical Engineering Research
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    • v.29 no.1
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    • pp.32-39
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    • 2008
  • This paper reports on a realtime OS based master-slave configuration robot control system for laparoscopic surgery robot which enables telesurgery and overcomes shortcomings with conventional laparoscopic surgery. Surgery robot system requires control system that can process large volume information such as medical image data and video signal from endoscope in real-time manner, as well as precisely control the robot with high reliability. To meet the complex requirements, the use of high-level real-time OS (Operating System) in surgery robot controller is a must, which is as common as in many of modem robot controllers that adopt real-time OS as a base system software on which specific functional modules are implemened for more reliable and stable system. The control system consists of joint controllers, host controllers, and user interface units. The robot features a compact slave robot with 5 DOF (Degree-Of-Freedom) expanding the workspace of each tool and increasing the number of tools operating simultaneously. Each master, slave and Gill (Graphical User Interface) host runs a dedicated RTOS (Real-time OS), RTLinux-Pro (FSMLabs Inc., U.S.A.) on which functional modules such as motion control, communication, video signal integration and etc, are implemented, and all the hosts are in a gigabit Ethernet network for inter-host communication. Each master and slave controller set has a dedicated CAN (Controller Area Network) channel for control and monitoring signal communication with the joint controllers. Total 4 pairs of the master/slave manipulators as current are controlled by one host controller. The system showed satisfactory performance in both position control precision and master-slave motion synchronization in both bench test and animal experiment, and is now under further development for better safety and control fidelity for clinically applicable prototype.

Development of Continuous Rainfall-Runoff Model for Flood Forecasting on the Large-Scale Basin (대유역 홍수예측을 위한 연속형 강우-유출모형 개발)

  • Bae, Deg-Hyo;Lee, Byong-Ju
    • Journal of Korea Water Resources Association
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    • v.44 no.1
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    • pp.51-64
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    • 2011
  • The objective of this study is to develop a continuous rainfall-runoff model for flood prediction on a large-scale basin. For this study, the hourly surface runoff estimation method based on the variable retention parameter and runoff curve number is developed. This model is composed that the soil moisture to continuous rainfall can be simulated with applying the hydrologic components to the continuous equation for soil moisture. The runoff can be simulated by linking the hydrologic components with the storage function model continuously. The runoff simulation to large basins can be performed by using channel storage function model. Nakdong river basin is selected as the study area. The model accuracy is evaluated at the 8 measurement sites during flood season in 2006 (calibration period) and 2007~2008 (verification period). The calibrated model simulations are well fitted to the observations. Nash and Sutcliffe model efficiencies in the calibration and verification periods exist in the range of 0.81 to 0.95 and 0.70 to 0.94, respectively. The behavior of soil moisture depending on the rainfall and the annual loadings of simulated hydrologic components are rational. From this results, continuous rainfall-runoff model developed in this study can be used to predict the discharge on large basins.

A Study on Analysis of Factors Affecting Technology Transfer Performance of Universities : An Approach to Different Types of Korean Universities (대학의 기술이전성과 영향요인 분석 : 대학의 유형별 접근)

  • Lee, Chang-Hak;Lee, Cheol-Gyu;Lee, Dong-Myung
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.12 no.9
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    • pp.3936-3951
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    • 2011
  • This paper aims to analyze factors affecting technology transfer performance according to different types of Korean universities and to conduct the research for the channel and extent of impact between these factors, utilizing 5 - year data for the technology transfers of 110 universities based on the survey by National Research Foundation of Korea. According to the analysis, incentive for researchers is the most crucial factor in local universities and small & medium-sized private universities located in the capital area. And numerical value of intellectual property rights owned by university is the key factor in universities specializing in science & engineering / industry. Also, Big-sized universities are heavily affected by the number of full-time faculty. In case of private universities, government subsidy relating to patents is critical factor for technology transfer performance. The mean value of all variables is a lot higher in participant universities than non-participant ones in CK(Connect Korea) project. In summary, it is suggested that steady financial support provided by the government is required and that mutual cooperation for industry-university-government is also needed for the commercialization of the technologies held by universities.