• Title/Summary/Keyword: parallel communication

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A 65-nm CMOS Low-Power Baseband Circuit with 7-Channel Cutoff Frequency and 40-dB Gain Range for LTE-Advanced SAW-Less RF Transmitters (LTE-Advanced SAW-Less 송신기용 7개 채널 차단 주파수 및 40-dB 이득범위를 제공하는 65-nm CMOS 저전력 기저대역회로 설계에 관한 연구)

  • Kim, Sung-Hwan;Kim, Chang-Wan
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.17 no.3
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    • pp.678-684
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    • 2013
  • This paper describes a low-power baseband circuit for SAW-less LTE-Advanced transmitters. The proposed transmitter baseband circuit consists of a 2nd-order Tow-Thomas type active RC-LPF and a 1st-order passive RC LPF. It can provide a 7 multi-channel cut-off frequencies and wide gain control range of -41 dB ~ 0 dB with a 1-dB step. The proposed 2nd-order active RC-LPF adopts an op-amp in which three other sub-op amps are in parallel connected to reduce DC current for different cutoff frequency. In addition, each sub-op amp adopts both Miller and feed-forward phase compensation method to achieve an UGBW of more than 1-GHz with a small DC power consumption. The proposed baseband circuit is implemented in 65-nm CMOS technology, consuming DC power from 6.3 mW to 24.1 mW from a 1.2V supply voltage for each different cut-off frequency.

DOVE : A Distributed Object System for Virtual Computing Environment (DOVE : 가상 계산 환경을 위한 분산 객체 시스템)

  • Kim, Hyeong-Do;Woo, Young-Je;Ryu, So-Hyun;Jeong, Chang-Sung
    • Journal of KIISE:Computing Practices and Letters
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    • v.6 no.2
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    • pp.120-134
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    • 2000
  • In this paper we present a Distributed Object oriented Virtual computing Environment, called DOVE which consists of autonomous distributed objects interacting with one another via method invocations based on a distributed object model. DOVE appears to a user logically as a single virtual computer for a set of heterogeneous hosts connected by a network as if objects in remote site reside in one virtual computer. By supporting efficient parallelism, heterogeneity, group communication, single global name service and fault-tolerance, it provides a transparent and easy-to-use programming environment for parallel applications. Efficient parallelism is supported by diverse remote method invocation, multiple method invocation for object group, multi-threaded architecture and synchronization schemes. Heterogeneity is achieved by automatic data arshalling and unmarshalling, and an easy-to-use and transparent programming environment is provided by stub and skeleton objects generated by DOVE IDL compiler, object life control and naming service of object manager. Autonomy of distributed objects, multi-layered architecture and decentralized approaches in hierarchical naming service and object management make DOVE more extensible and scalable. Also,fault tolerance is provided by fault detection in object using a timeout mechanism, and fault notification using asynchronous exception handling methods

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A fundamental study on the installation methods of automatic identification buoy on coastal gill net (연안자망 부이에 어구자동식별 장치 설치방안에 관한 기초적 연구)

  • HEO, Nam-Hee;KANG, Kyoung-Bum;KOO, Myeong-Seong;KIM, Keun-Hyong;KIM, Jong-Bum;JWA, Min-Seok;KIM, Jun-Teck;JOUNG, Joo-Myeong;KIM, Byung-Yeob;KIM, Suk-Jong
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.55 no.4
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    • pp.294-302
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    • 2019
  • As a series of fundamental researches on the development of an automatic identification monitoring system for fishing gear. Firstly, the study on the installation method of automated identification buoy for the coastal improvement net fishing net with many loss problems on the west coast was carried out. Secondly, the study was conducted find out how to install an automatic identification buoy for coastal gill net which has the highest loss rate among the fisheries. GPS for fishing was used six times in the coastal waters around Seogwipo city in Jeju Island to determine the developmental status and underwater behavior to conduct a field survey. Next, a questionnaire was administered in parallel on the type of loss and the quantity and location of fishing gear to be developed and the water transmitter. In the field experiment, the data collection was possible from a minimum of 13 hours, ten minutes to a maximum of 20 hours and ten minutes using GPS, identifying the development status and underwater behavior of the coastal gillnet fishing gear. The result of the survey showed that the loss of coastal net fishing gear was in the following order: net (27.3%), full fishing gear (24.2%), buoys, and anchors (18.2%). The causes were active algae (50.0%), fish catches (33.3%) and natural disasters (12.5%). To solve this problem, the installation method is to attach one and two electronic buoys to top of each end of the fishing gear, and one underwater transmitter at both ends of the float line connected to the anchor. By identifying and managing abnormal conditions such as damage or loss of fishing gear due to external factors such as potent algae and cutting of fishing gear, loss of fishing gear can be reduced. If the lost fishing gear is found, it will be efficiently collected.

Effects of Personality Virtues Education Program Using Visual Media for College Students (영상매체를 활용한 전문대학생들의 인성덕목 교육프로그램 효과)

  • Jin, Eun-Hee;Kim, Hun-Hee
    • The Journal of the Korea Contents Association
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    • v.17 no.1
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    • pp.12-24
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    • 2017
  • The purpose of this study was to evaluate the effects of personality virtue education program using visual media for college students. This program was run in parallel with "Educational Psychology" lecture from August 30th through December 4th, 2015. The subjects of study were 348 freshmen of nursing department in J college. The methodology of this study was nonequivalent pretest-posttest control group experimental design. The researcher carried out pretest for experimental group and control group both before program execution by KEDI Personality Inventory and repeated the test afterwards to measure the effects of the program. The data analysis was implemented by SPSS 22.0. The ANCOVA was used to verify the hypothesis. The result showed that all personality virtues(self-respect, integrity, consideration communication, responsibility, etiquette, self-control, honesty courage, wisdom, justice, citizenship) scores were improved significantly after the program. In conclusion, virtue-centered personality education can make students realize and internalize the value of virtues and have motivation and will to act, when they empathized with visual media on the various situation and learned repeatedly in integrated curriculum.

Sex Differences in Preference Style for Navigation Design (네비게이션 디자인에 있어 성별에 따른 선호 스타일 연구)

  • Kim Soon-Deok;Seo Jong-Hwan
    • Science of Emotion and Sensibility
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    • v.8 no.3
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    • pp.221-229
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    • 2005
  • This study aimed to understand the sex differences in cognitive behaviors in website design and demonstrate a practical basis for utilizing these differences into more user-centered design concept. Especially, we focused on the sex-different preference according to the information architecture of website navigation. First, We investigated general differences between men and women in cognitive behaviors through various literature studies. According to our investigation, men's cognitive works generally tend to follow a regular sequence and proceed step by step. On the other hand, women's cognitive style is generally characterized by random generation and simultaneous progress. To examine that these differences can be found in use of website navigation, we made an experiment in website design. We designed several test websites that have same contents but different style of navigation structure. A similar number of men and women were chosen for this test and they implemented given tasks. During the test, participants reported their preference on each websites and their implementing time and number of errors were collected. Based on the analysis of test data, it was possible to conclude that male participants' preference for the navigation with a narrow and deep information structure is relatively higher than female participants' preference for the same navigation, On the other hand, female participants have a preference of the navigation with a broad and swallow information structure. The result of study showed that there is a close correlation between the sex differences in preference of navigation types and the general sex differences in cognitive behavior. This finding can be used as a basis for designing the website navigation in which sex differences are reflected.

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The Parallelization Effectiveness Analysis of K-DRUM Model (분포형 강우유출모형(K-DRUM)의 병렬화 효과 분석)

  • Chung, Sung-Young;Park, Jin-Hyeog;Hur, Young-Teck;Jung, Kwan-Sue
    • Journal of Korean Society for Geospatial Information Science
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    • v.18 no.4
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    • pp.21-30
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    • 2010
  • In this paper, the parallel distributed rainfall runoff model(K-DRUM) using MPI(Message Passing Interface) technique was developed to solve the problem of calculation time as it is one of the demerits of the distributed model for performing physical and complicated numerical calculations for large scale watersheds. The K-DRUM model which is based on GIS can simulate temporal and spatial distribution of surface flow and sub-surface flow during flood period, and input parameters of ASCII format as pre-process can be extracted using ArcView. The comparison studies were performed with various domain divisions in Namgang Dam watershed in case of typoon 'Ewiniar' at 2006. The numerical simulation using the cluster system was performed to check a parallelization effectiveness increasing the domain divisions from 1 to 25. As a result, the computer memory size reduced and the calculation time was decreased with increase of divided domains. And also, the tool was suggested in order to decreasing the discharge error on each domain connections. The result shows that the calculation and communication times in each domain have to repeats three times at each time steps in order to minimization of discharge error.

Development of Network Based MT Data Processing System (네트워크에 기반한 MT자료의 처리기술 개발 연구)

  • Lee Heuisoon;Kwon Byung-Doo;Chung Hojoon;Oh Seokhoon
    • Geophysics and Geophysical Exploration
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    • v.3 no.2
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    • pp.53-60
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    • 2000
  • The server/client systems using the web protocol and distribution computing environment by network was applied to the MT data processing based on the Java technology. Using this network based system, users can get consistent and stable results because the system has standard analysing methods and has been tested from many users through the internet. Users can check the MT data processing at any time and get results during exploration to reduce the exploration time and money. The pure/enterprised Java technology provides facilities to develop the network based MT data processing system. Web based socket communication and RMI technology are tested respectively to produce the effective and practical client application. Intrinsically, the interpretation of MT data performing the inversion and data process requires heavy computational ability. Therefore we adopt the MPI parallel processing technique to fit the desire of in situ users and expect the effectiveness for the control and upgrade of programing codes.

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Quadratic Sigmoid Neural Equalizer (이차 시그모이드 신경망 등화기)

  • Choi, Soo-Yong;Ong, Sung-Hwan;You, Cheol-Woo;Hong, Dae-Sik
    • Journal of the Korean Institute of Telematics and Electronics S
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    • v.36S no.1
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    • pp.123-132
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    • 1999
  • In this paper, a quadratic sigmoid neural equalizer(QSNE) is proposed to improve the performance of conventional neural equalizer in terms of bit error probability by using a quadratic sigmoid function as the activation function of neural networks. Conventional neural equalizers which have been used to compensate for nonlinear distortions adopt the sigmoid function. In the case of sigmoid neural equalizer, each neuron has one linear decision boundary. So many neurons are required when the neural equalizer has to separate complicated structure. But in case of the proposed QSNF and quadratic sigmoid neural decision feedback equalizer(QSNDFE), each neuron separates decision region with two parallel lines. Therefore, QSNE and QSNDFE have better performance and simpler structure than the conventional neural equalizers in terms of bit error probability. When the proposed QSNDFE is applied to communication systems and digital magnetic recording systems, it is an improvement of approximately 1.5dB~8.3dB in signal to moise ratio(SNR) over the conventional decision feedback equalizer(DEF) and neural decision feedback equalizer(NDFE). As intersymbol interference(ISI) and nonlinear distortions become severer, QSNDFE shows astounding SNR shows astounding SNR performance gain over the conventional equalizers in the same bit error probability.

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Occupational Therapy Intervention for Improving Play of Children : A Systematic Review (아동의 놀이 향상을 위한 작업치료 중재에 관한 체계적 고찰)

  • Lee, Sun-Hee;Park, Hae Yean
    • The Journal of Korean Academy of Sensory Integration
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    • v.15 no.2
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    • pp.93-106
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    • 2017
  • Objective : The purpose of this study is to provide an evidence for clinical practice by systemic analysis on occupational therapy interventions for improvement of children's play. Methods : Articles used in this study were collected from database of Pubmed, ProQuest, EBSCOhost, Scopus, RISS, KISS, and National Library of Korea. The key words used in the search were "Play AND Occupational Therapy AND (Intervention OR Treatment)" and the publication period was limited from January 2007 to April 2017. 11 articles in total were selected for the systematic review analysis. Results : The results revealed that the majority of studies was one-group non-randomized study and the majority of intervention used was play-based intervention in case of that play itself was the intervention goal. The most frequently used environment for the intervention was parallel setting of home and treatment room. The majority of studies was for children with ADHD and the most commonly used assessment tool was Test of Playfulness (ToP). Dependent variables measured along with play were language skills, social interactive skills, communication and pragmatic skills, problem-solving skills, caregiver responsiveness, and parent-child interaction. Conclusion : This study help to understand the current state of occupational therapy intervention for improvement of children's play. Starting with the understanding, it is expected that various studies on play of children will be done in the future.

Efficient RMESH Algorithms for Computing the Intersection and the Union of Two Visibility Polygons (두 가시성 다각형의 교집합과 합집합을 구하는 효율적인 RMESH 알고리즘)

  • Kim, Soo-Hwan
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.20 no.2
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    • pp.401-407
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    • 2016
  • We can consider the following problems for two given points p and q in a simple polygon P. (1) Compute the set of points of P which are visible from both p and q. (2) Compute the set of points of P which are visible from either p or q. They are corresponding to the problems which are to compute the intersection and the union of two visibility polygons. In this paper, we consider algorithms for solving these problems on a reconfigurable mesh(in short, RMESH). The algorithm in [1] can compute the intersection of two general polygons in constant time on an RMESH with size O($n^3$), where n is the total number of vertices of two polygons. In this paper, we construct the planar subdivision graph in constant time on an RMESH with size O($n^2$) using the properties of the visibility polygon for preprocessing. Then we present O($log^2n$) time algorithms for computing the union as well as the intersection of two visibility polygons, which improve the processor-time product from O($n^3$) to O($n^2log^2n$).