• Title/Summary/Keyword: 충돌속도

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Peducing the Overhead of Virtual Address Translation Process (가상주소 변환 과정에 대한 부담의 줄임)

  • U, Jong-Jeong
    • The Transactions of the Korea Information Processing Society
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    • v.3 no.1
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    • pp.118-126
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    • 1996
  • Memory hierarchy is a useful mechanism for improving the memory access speed and making the program space larger by layering the memories and separating program spaces from memory spaces. However, it needs at least two memory accesses for each data reference : a TLB(Translation Lookaside Buffer) access for the address translation and a data cache access for the desired data. If the cache size increases to the multiplication of page size and the cache associativity, it is difficult to access the TLB with the cache in parallel, thereby making longer the critical timing path in the processor. To achieve such parallel accesses, we present the hybrid mapped TLB which combines a direct mapped TLB with a very small fully-associative mapped TLB. The former can reduce the TLB access time. while the latter removes the conflict misses from the former. The trace-driven simulation shows that under given workloads the proposed TLB is effective even when a fully-associative mapped TLB with only four entries is added because the effects of its increased misses are offset by its speed benefits.

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A study on the electron ionization and attachment coefficients ins $SF_6$ gas ($SF_6$ 가스의 전리 및 부착계수에 관한 연구)

  • Seo, Sang-Hyeon;Yu, Heoi-Young;Kim, Sang-Nam;Ha, Sung-Chul
    • The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.10 no.6
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    • pp.96-103
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    • 1996
  • This paper describes the electron transport characteristics in SF6 gas calculated for range of E/N values from 150~ 800[Td) by the Monte Carlo simulation and Boltzmann equation method using a set of electron collision cross sections detennined by the authors and the values of electron swarm parameters are obtained by TOF method. The results gRined that the values of the electron swarm parameters such as the electron drift velocity, the electron ionization or Rttachment coefficients, longitudinal and transverse diffusion coefficients agree with the experimental and theoretical for a range of E/N. The properties of electron avalanches is concerned electron energy non--equilibrium region. The electron energy distributions function were analysed in sulphur hexafluoride at E/N : 500~800[Td) for a case of non-equilibrium region in the mean electron energy. The validity of the results obtained has been confilll1ed by a TOF method.

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The Test for Verifying a Tip-Over Analysis of a Dry Storage Cask (건식저장용기에 대한 전복해석의 검증시험)

  • Kim Dong-Hak;Seo Ki-Seog;Lee Ju-Chan;Cho Chun-Hyung;Jang Hyun-Kee;Choi Byung-Il
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.4 no.3
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    • pp.245-253
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    • 2006
  • A test of the 1/3 scale model was conducted to verify the tip-over analysis of a dry. concrete storage cask under a hypothetical accident condition. The tip-over analysis was executed using the velocity at each point as the initial conditions of the model just before the impact. The initial velocity was determined from the initial angular velocity, which would make the equivalent kinetic energy to the potential energy. To confirm the structural integrity of the canister, the visual testing and the non-detective testings such as Liquid Penetrant testing and Ultrasonic Testing were conducted. The lid of a storage cask was plastically deformed near the impact point. The structural integrity of storage cask was maintained. To verify the tip-over analysis the strains and the accelerations acquired by the tip-over test were compared with those by the analyses. The results of the analysis were larger than the test results about two times.

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Influence of Impact Angle on Deformation in Proximal Femur during Slide Falling (측방 낙상시의 충격 각도가 대퇴골 근위부의 변형에 미치는 영향)

  • 김병수;배태수;김정규;최귀원
    • Journal of Biomedical Engineering Research
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    • v.24 no.3
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    • pp.233-239
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    • 2003
  • Falling related injuries are categorized as the most serious and common medical problems experienced by the elderly, hip joint fracture, one of the most serious consequences of falling in the elderly, occurs in only about 1% of falling. Nevertheless, hip fracture accounts for a considerable part of the disability, death, and medical costs associated with falling. In this study, we considered the impact angle and displacement rate in falling as another factor affecting femoral strength. Using a fresh-frozen human femur, we developed system to simulate the falling condition and then conducted the experiments changing the impact angle (0$^{\circ}$, 15$^{\circ}$, 30$^{\circ}$) of proximal femur. Also, in order to analyze the relative risk due to falling to normal situation in proximal femur, we did the static test simulating the two-legged stance condition. The results showed that the change in impact angle affected the strain distribution in proximal femur, and that a large deformation in femoral neck than in other sites. Furthermore despite low impact velocity, a large deformation in proximal femur occurred in the impact test and different strain distribution was observed compare to the static case.

Addressing Big Data solution enabled Connected Vehicle services using Hadoop (Hadoop을 이용한 스마트 자동차 서비스용 빅 데이터 솔루션 개발)

  • Nkenyereye, Lionel;Jang, Jong-Wook
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.19 no.3
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    • pp.607-612
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    • 2015
  • As the amount of vehicle's diagnostics data increases, the actors in automotive ecosystem will encounter difficulties to perform a real time analysis in order to simulate or to design new services according to the data gathered from the connected cars. In this paper, we have conducted a study of a Big Data solution that expresses the essential deep analytics to process and analyze vast quantities of vehicles on board diagnostics data generated by cars. Hadoop and its ecosystems have been deployed to process a large data and delivered useful outcomes that may be used by actors in automotive ecosystem to deliver new services to car owners. As the Intelligent transport system is involved to guarantee safety, reduce rate of crash and injured in the accident due to speed, addressing big data solution based on vehicle diagnostics data is upcoming to monitor real time outcome from it and making collection of data from several connected cars, facilitating reliable processing and easier storage of data collected.

Explosion Casting: An Efficient Selection Method for Overlapped Virtual Objects in Immersive Virtual Environments (몰입 가상현실 환경에서 겹쳐진 가상객체들의 효율적인 선택을 위한 펼침 시각화를 통한 객체 선택 방법)

  • Oh, JuYoung;Lee, Jun
    • The Journal of the Korea Contents Association
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    • v.18 no.3
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    • pp.11-18
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    • 2018
  • To interact with a virtual object in immersive virtual environment, the target object should be selected quickly and accurately. Conventional 3D ray casting method using a direction of user's hand or head allows the user to select an object quickly. However, accuracy problem occurs when selecting an object using conventional methods among occlusion of objects. In this paper, we propose a region of interest based selection method that enables to select an object among occlusion of objects using a combination of gaze tracking and hand gesture recognition. When a user looks at a group of occlusion of objects, the proposed method recognizes user's gaze input, and then region of interest is set by gaze input. If the user wants to select an object among them, the user gives an activation hand gesture. Then, the proposed system relocates and visualizes all objects on a virtual active window. The user can select an object by a selecting hand gesture. Our experiment verified that the user can select an object correctly and accurately.

Structural Safety Assessment of Mark III Membrane Type Liquid Natural Gas Cargo Containment System under Ice Collision (빙 충돌에 대한 Mark III 멤브레인형 LNG CCS의 구조 안전성 평가)

  • Nho, In Sik;Yun, Young-Min;Park, Man-Je;Oh, Young-Taek;Kim, Sung-Chan
    • Journal of Ocean Engineering and Technology
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    • v.28 no.2
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    • pp.126-132
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    • 2014
  • In this study, a method for analyzing the collision and interaction between ice bergy bits and a Mark III type liquid natural gas (LNG) carrier was considered, and the structural safety of a ship's hull and cargo containment system (CCS) was evaluated. In the analysis, a constitutive model implementing the strain rate dependant mechanical property was used to consider the typical material characteristics of ice rationally. A relatively simple and easy ice structure interaction analysis procedure, compared with the accurate but complicated FSI analysis scheme, was suggested. When the ice bergy bits collided with ship's side hull under the four assumed scenarios, the structural behaviors of the ship structure and LNG CCS were simulated by applying the suggested ice collision analysis procedure using the commercial hydro-code LS-DYNA. In addition, the effects of the shapes and colliding speed of the ice bergy bits on the ice-structure interaction and safety of the CCS were examined in detail.

Design and Implementation of HomePNA 2.0 MAC Controller Circuit (HomePNA 2.0 MAC Controller 회로의 설계 및 구현)

  • Kim, Jong-Won;Kim, Dae-Young
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.31 no.1A
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    • pp.1-10
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    • 2006
  • The Home Phoneline Networking Alliance(HomePNA) 2.0 technology can establish a home network using existing in-home phone lines, which provides a channel rate of 4-32 Mbps. HomePNA 2.0 Medium Access Control(MAC) protocol adopts an IEEE 802.3 Carrier Sense Multiple Access with Collision Detection(CSMA/CD) access method, Quality of Service(QoS) algorithm, and Distributed Fair Priority Queuing(DFPQ) collision resolution algorithm. In this paper, we describe some performance analysis results of HomePNA 2.0 MAC protocol and the requirements of HomePNA 2.0 MAC controller. Then, we propose the architecture of HomePNA 2.0 MAC controller circuit, show the simulation result of each block included in HomePNA 2.0 MAC controller, and present the HomePNA 2.0 transceiver chip that we have implemented.

Mobile robot control by MNN using optimal EN (최적 EN를 사용한 MNN에 의한 Mobile Robot제어)

  • Choi, Woo-Kyung;Kim, Seong-Joo;Seo, Jae-Yong;Jeon, Hong-Tae
    • Journal of the Korean Institute of Intelligent Systems
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    • v.13 no.2
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    • pp.186-191
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    • 2003
  • Skills in tracing of the MR divide into following, approaching, avoiding and warning and so on. It is difficult to have all these skills learned as neural network. To make this up for, skills consisted of each module, and Mobile Robot was controlled by the output of module adequate for the situation. A mobile Robot was equipped multi-ultrasonic sensor and a USB Camera, which can be in place of human sense, and the measured environment information data is learned through Modular Neural Network. MNN consisted of optimal combination of activation function in the Expert Network and its structure seemed to improve learning time and errors. The Gating Network(GN) used to control output values of the MNN by switching for angle and speed of the robot. In the paper, EN of Modular Neural network was designed optimal combination. Traveling with a real MR was performed repeatedly to verity the usefulness of the MNN which was proposed in this paper. The robot was properly controlled and driven by the result value and the experimental is rewarded with good fruits.

A Comparison & Analysis of Electronic Commerce of Korea's FTA (한국의 FTA전자상거래규정 비교·분석)

  • Kim, Yun-keun;Park, Bok-Jae
    • International Commerce and Information Review
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    • v.19 no.2
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    • pp.25-44
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    • 2017
  • Though electronic commerce has grown rapidly in international trade, there is no basic consensus for its concept and rule applied. So WTO has done practice of not imposing customs duties on digital contents and been researching overall on electronic commerce through Work Program while many countries of the world attempt to obtain their interests by stipulating chapter of electronic commerce in their FTAs. This paper has compared and analysed chapter of electronic commerce in all the FTAs which Korea has signed and enforced. Korea's FTA stipulates commonly no customs duties, the other chapter's priority when chapter of electronic commerce conflicts the other chapter, electronic authentication, protection of personal information and consumer protection. But it has weak consistency and framework as it has different provisions for the objects of electronic commerce respectively, reserves classification & applied rule for electronic commerce, stipulates differently on non discrimination treatment and so on. Korea should participate in the research of international organization including WTO and cope actively and elastically by analysing the provisions of electronic commerce of the other countries' FTA such as USA, EU, CHINA and so on.

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