• Title/Summary/Keyword: Research Information Systems

Search Result 12,228, Processing Time 0.047 seconds

Improved Equalization Performance for DVB-T2 based on Data Reuse (데이터 재사용기반 DVB-T2 등화 성능 개선)

  • Kang, Eun-Su;Han, Dong-Seog
    • Journal of the Institute of Electronics Engineers of Korea TC
    • /
    • v.49 no.8
    • /
    • pp.33-38
    • /
    • 2012
  • An equalization algorithm is proposed for digital video broadcasting - terrestrial version 2 (DVB-T2) systems to minimize the noise effect. It is done by averaging frequency-domain data and channel responses obtained with different signal intervals for the same orthogonal frequency division multiplexing (OFDM) symbol. Its performance is evaluated by computer simulations along with comparison of conventional algorithms.

The research of calibration methods for High-performance D/A Converters (고성능 D/A 변환기를 위한 보정 기법 연구)

  • Kim, Soo-Jae;Hwang, Jung-Jin;Yoon, Kwang-Sub
    • Proceedings of the IEEK Conference
    • /
    • 2008.06a
    • /
    • pp.553-554
    • /
    • 2008
  • In a general way, Current scaling DACs are used in wireless communication systems. But there are degradations of important factors because of mismatch of current source corresponding to high resolution. To solve the problem, Calibration methods are researched lately. Mismatch of current source is corrected by Calibration method and then corrected current values are delivered to Core DAC. As a results, Degradations of important factors that produced by increment of non-linearity are suppressed by calibration method.

  • PDF

Presentation of a Fault Detecting Method for Power Transmission Line using M-sequence

  • Nishiyama, E.;Kuwanmi, K.
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 2001.10a
    • /
    • pp.86.2-86
    • /
    • 2001
  • The method of pinpointing the place of the abnormalities of a power transmission system analyzes the voltage and the current information from the both ends of a power [1-2]. Now, there are only current and a voltage measuring instrument every about 20km, and the present condition is specifying the breaking down point by viewing of a worker in it. In this research, a power line circuit is assumed to be a line type system, and M-sequence is impressed to the end, it receives at other ends, the crosscorrelation function of input and output is taken, an impulse response is calculated, and the method in comparison with the time of normal is proposed. By this technique ...

  • PDF

A Study on Arc Force Sensor for a Robotic Welding Control System

  • Son, Joon-Sik;Kim, Ill-Soo;Choi, Seung-Gap;Kueon, Yeong-Seob;Lee, Duk-Man
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 2001.10a
    • /
    • pp.128.5-128
    • /
    • 2001
  • This paper presents investigation of an arc force sensor for a robotic welding control system. Arc force sensor is employed in this research to monitor the bead geometry of the arc welding process. Arc force sensor mounted at the end of the robot wrist was employed to measure the arc force applied to the weld. Experimental configuration for measurement of arc force was used to quantify the changes in the arc force distributions of the plate being welded. A relationship between the bead dimension and the arc force distributions was established. The sensor information was used to establish a relationship between welding current and arc force. Arc force sensor have shown to be one of the most sophisticated technique to monitor perturbations that occurred during robotic arc welding process.

  • PDF

The Measurement of Stewart Platform applied to the Tele - Operated Vehicle System by Forward Kinematics

  • Lee, K.Y.;Choi, J.H.;Seo, B.W.;Kim, J.H.
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 2001.10a
    • /
    • pp.126.2-126
    • /
    • 2001
  • This paper, the integration of driving simulator and unmanned vehicle by means of new concept for better performance through a tele-operated system is suggested. But autonomous system is one of the most difficult research topics from the point of view of several constrains on mobility, speed of vehicle and lack of environmental information. In these days, however, many innovations on the vehicle provide the appropriate automatic control in vehicle subsystem for reducing human error. This tendency is toward to the unmanned vehicle or the tele-operated vehicle ultimately. This paper describes the motion system ...

  • PDF

Pose Estimation of an Object from X-ray Images Based on Principal Axis Analysis

  • Roh, Young-Jun;Cho, Hyung-Suck
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 2002.10a
    • /
    • pp.97.4-97
    • /
    • 2002
  • 1. Introduction Pose estimation of a three dimensional object has been studied in robot vision area, and it is needed in a number of industrial applications such as process monitoring and control, assembly and PCB inspection. In this research, we propose a new pose estimation method based on principal axes analysis. Here, it is assumed that the locations of x-ray source and the image plane are predetermined and the object geometry is known. To this end, we define a dispersion matrix of an object, which is a discrete form of inertia matrix of the object. It can be determined here from a set of x-ray images, at least three images are required. Then, the pose information is obtained fro...

  • PDF

Study on muscle deformation and human body modeling (근육 변형 및 인체 모델링에 관한 연구)

  • 이환용;김명수;박찬모
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 1991.10a
    • /
    • pp.752-757
    • /
    • 1991
  • Recently, human body modeling with muscle deformation has become an attractive research area in computer animation. There are many modeling tools available for solids such as mechanical part. However, there are many limitations of these conventional methods in modeling flexible objects with delicate motions and shapes such as human bodies. In this paper we present a new modeling technique for human body with muscle deformation. Each muscle is represented as a generalized cylinder and its shape deformation is computed using simple algorithm. The human body is a union of muscles, bones, organs, etc. The modeling data are obtained from the information on the human anatomy. To demonstrate the feasibility of our method, we model several arm muscles and simulate the skin deformation. As a result we have obtained a realistic shape deformation.

  • PDF

Implementation of a Network Processor for Wireless LAN (무선 LAN용 네트웍 프로세서의 설계)

  • 김선영;박성일;박인철
    • Proceedings of the IEEK Conference
    • /
    • 2000.11b
    • /
    • pp.184-187
    • /
    • 2000
  • A network is an important portion of communications in these days. Because of many inconveniences of a wired-network, wireless solutions have been studied for many years. One of the results of those efforts is IEEE 802.11, wireless LAN. This paper briefly summarizes wireless LAN and specially focuses on the design of a network processor for the wireless LAN system. The processor has 16-bit instruction set suitably selected for network processing and low-power consumption. It is implemented and verified with a wireless LAN system model. The wireless LAN system is modeled in RTL excluding the RF module. The processor can be used in many wireless systems as a controller and utilized as a test module for the research of low-power schemes.

  • PDF

Performance Analysis of a Discrete-Time Two-Phase Queueing System

  • Kim, Tae-Sung;Chang, Seok-Ho;Chae, Kyung-Chul
    • ETRI Journal
    • /
    • v.25 no.4
    • /
    • pp.238-246
    • /
    • 2003
  • This paper introduces the modeling and analysis of a discrete-time, two-phase queueing system for both exhaustive batch service and gated batch service. Packets arrive at the system according to a Bernoulli process and receive batch service in the first phase and individual services in the second phase. We derive the probability generating function (PGF) of the system size and show that it is decomposed into two PGFs, one of which is the PGF of the system size in the standard discrete-time Geo/G/1 queue without vacations. We also present the PGF of the sojourn time. Based on these PGFs, we present useful performance measures, such as the mean number of packets in the system and the mean sojourn time of a packet.

  • PDF

Novel Pharmacological Treatment for Depression (새로운 우울증 치료 약물)

  • Jeong, Hee Jeong;Moon, Eunsoo
    • Korean Journal of Biological Psychiatry
    • /
    • v.23 no.1
    • /
    • pp.1-11
    • /
    • 2016
  • Development of various antidepressants such as monoamine oxidase inhibitors, tricyclic antidepressants, selective serotonin reuptake inhibitors, serotonin norepinephrine reuptake inhibitors, and noradrenergic and specific serotonergic antidepressant has led to a tremendous progression of pharmaceutical treatment for depression, but still there are some limitations of current antidepressants, such as treatment-resistant depression and delayed onset of antidepressants. The pathogenesis of depression is unclear because depression is a heterogeneous disease state, and the mechanisms of antidepressants remain uncertain as well. Nevertheless, in an attempt to develop novel antidepressants, some trials have been conducted based on the potential biological mechanism discovered in the numerous research results. This review will provide information about the potential novel antidepressants and the current states of clinical studies using them. In particular, some potential novel antidepressants anti-inflammatory agents, antioxidants, anticholinergics, modulators of Hypothalamic Pituitary Adrenal Axis, glutamate, and opioid systems, as well as some neuropeptides such as susbstance P, neuropeptide Y, and galanin will be discussed.