• Title/Summary/Keyword: combined systems

Search Result 2,639, Processing Time 0.027 seconds

Development of a distributed rainfall-runoff model with TIN-based topographic representation and its application to an analysis of spacial variability of soil properties on runoff response

  • Tachikawa, Yasuto;Shiiba, Michiharu
    • Proceedings of the Korea Water Resources Association Conference
    • /
    • 2000.05a
    • /
    • pp.28-36
    • /
    • 2000
  • A TIN, Triangulated Irregular Network, based topographic modeling method and a distributed rainfall-runoff model using the topographic representation is presented. In the TIN based topographic representation, a watershed basin is modeled as a set of contiguous non-overlapping triangular facets: the watershed basin is subdivided according to streamlines to deal with water movement one-dimensionally; and each partitioned catchment is approximated to a slope element having a quasi-three-dimensional shape by using cubic spline functions. On an approximated slope element, water movement is represented by combined surface-subsurface kinematic wave equations considering a change of slope gradient and slope width. By using the distributed rainfall-runoff model, the effects of spatial variability of soil properties on runoff response are examined.

  • PDF

General Pharmacology of DA-7101, a New Antibiotic Composition (새로운 복합항생제 DA-7101의 일반약리작용)

  • 김정훈;오태영;배은주;손문호;김순회;김원배
    • Biomolecules & Therapeutics
    • /
    • v.7 no.3
    • /
    • pp.285-291
    • /
    • 1999
  • DA-7101 is a new combined formulation of cefatrizine:clavulanic acid (2:1) under development as oral abtibiotics. The general pharmacological properties of DA-7101 on central nervous, cardiovascular, gas-trointestinal and other organ systems were studied by oral administration, in vivo and in vitro. DA-7101 had no marked effects all tests studied such as general behavior, hexobarbital-induced sleeping, spontaneous activity, anticonvulsion, body temperature, acetic acid-induced writhing, rotarod performance, heart rate and blood pressure in cats, isolated ileum movement, intestinal transition, gastric juice secretion and urine volume and electrolytes in rats. But exceptionally at the highest dose of 900 mg/kg, DA-7101 increased hexobarbital-induced sleeping time, caused a slight hypotension and decreased the secretion of gastric juice. These results suggest that at the estimated clinical dose DA-7101 would not bring about any serious acute adverse effects clinically.

  • PDF

A Study on the Performance Improvement and Simplification of the Modulator for Vehicle Stability Control System (차량 안정성 제어 시스템의 모듈레이터 성능개선 및 단순화에 관한 연구)

  • 이종찬;송창섭
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.21 no.6
    • /
    • pp.84-93
    • /
    • 2004
  • This study carries out the performance improvement and simplification of hydraulic modulator that plays an important role in vehicle stability control systems. The mathematical models for each component of a modulator, such as pump, wheel cylinder, check and solenoid valve, accumulator, damper are derived in detail. All the mathematical models are combined to form a modulator system and implemented through a computer program, which can be controlled by a user friendly GUI. To verity the simulation, comparison between simulation and experiments has been made. After the verification of the validity of the simulation, the effects of the design parameters of the modulator on the wheel cylinder pressure is investigated. The results show that the modulator without MPA has advantage in early time pressure rise rate, and it can be simplified.

A study on PV-AF-SPE system connected with utility (계통 연계형 PV-AF-SPE 시스템에 관한 연구)

  • Lee, Dong-Han;Lee, Suk-Ju;Kim, Jong-Hyun;Park, Min-Won;Yu, In-Keun
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 2006.06a
    • /
    • pp.117-120
    • /
    • 2006
  • In this paper an integrated model of PV-AF (Photovoltaic-Active Filter) and PV-SPE(Photovoltaic Solid Polymer Electrolyte) system using PSCAD/EMTDC were explained in detaiil. The main concept of PV-AF system starts from the 'harmonics'. In order to deliver power to utility, PV system essentially needs a converter system. Here PV-AF system adds the function of active filter to the converter system installed in PV system, which was introduced already in several papers. PV-SPE system has been studied as a replacement of existing hydrogen production technology that emits large amount of carbon dioxide into atmosphere. Until now, these two systems, PV-AF and PV-SPE, have been considered separately However, in this paper, characteristics and advantages of combined system are discussed in detail.

  • PDF

Complete Modeling of an Ultrasonic NDE Measurement System - An Electroacoustic Measurement Model

  • Dang, Changjiu;Lester W. Schmerr, Jr.
    • Journal of the Korean Society for Nondestructive Testing
    • /
    • v.21 no.1
    • /
    • pp.1-21
    • /
    • 2001
  • It will be shown how models can simulate all the elements of an ultrasonic NDE measurement system, including the pulser/receiver, cabling, transducer(s), and the acoustic/elastic waves fields. When combined, these models form what is called the electroacoustic measurement model. It will be demonstrated how this electroacoustic measurement model can be used to conduct parametric transducer and system studies and how the model can form the basis for experimentally characterizing all the elements of the ultrasonic measurement system, using purely electrical measurements.

  • PDF

New HRTFs (Head Related Transfer Functions) and Applications to the Virtual Acoustic Imaging Systems (가상입체음향 시스템 개발을 위한 새로운 머리전달 함수(HRTF) 소개 및 응용)

  • Kim, Young-Tae;Kim, Sun-Min
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 2005.11a
    • /
    • pp.616-619
    • /
    • 2005
  • An extensive data base of HRTFs (Head Related Transfer Functions) has been established in order to work with high qualifies of 3D acoustic appliances. The basic specifications of the measurement presented are that a spatial resolution of 10$^{\circ}$ in elevation angles (ranging from -40$^{\circ}$ to 90$^{\circ}$) and uniform spatial resolution of 5$^{\circ}$ in azimuth angles. The distance from the measurement sources to the centre of the dummy head is 2m and the sampling frequency is 48 kHz and the quantisation depth is 24-bits. The data is presented for three arrangements of pinna models (large, small and no pinna) which were combined with the open and blocked ear canal cases to give a total of 6 sets of measurements. The data base may contribute to show promise of providing useful applications of 3D sound.

  • PDF

A Study on Development of an Active Hybrid Mount for Naval Shipboard Equipment (함정 탑재장비용 능동 하이브리드 마운트 개발에 대한 연구)

  • Moon, S.J.;Choi, S.M.;Jeong, J.A.;Choi, S.B.;Jung, W.J.;Koo, J.Y.
    • Transactions of the Korean Society for Noise and Vibration Engineering
    • /
    • v.20 no.7
    • /
    • pp.685-692
    • /
    • 2010
  • A hybrid mount for shipboard machinery installed on naval ships was developed. The mount is combined with a rubber mount and a piezostack actuator. The rubber mount is one of the most popular and effective passive mounts to have been applied to various vibration systems to date. The piezostack actuator is featured by a fast response time, small displacement and low power consumption. Through a series of experimental tests conducted in accordance with MIL-M-17185A(SHIPS), MIL-M-17508F(SH), and MIL-S-901D which are US military specifications related to the performance requirements of the mount, it has been confirmed that the hybrid mount shows more effective performance for use in naval ships.

Video-based Height Measurements of Multiple Moving Objects

  • Jiang, Mingxin;Wang, Hongyu;Qiu, Tianshuang
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.8 no.9
    • /
    • pp.3196-3210
    • /
    • 2014
  • This paper presents a novel video metrology approach based on robust tracking. From videos acquired by an uncalibrated stationary camera, the foreground likelihood map is obtained by using the Codebook background modeling algorithm, and the multiple moving objects are tracked by a combined tracking algorithm. Then, we compute vanishing line of the ground plane and the vertical vanishing point of the scene, and extract the head feature points and the feet feature points in each frame of video sequences. Finally, we apply a single view mensuration algorithm to each of the frames to obtain height measurements and fuse the multi-frame measurements using RANSAC algorithm. Compared with other popular methods, our proposed algorithm does not require calibrating the camera, and can track the multiple moving objects when occlusion occurs. Therefore, it reduces the complexity of calculation and improves the accuracy of measurement simultaneously. The experimental results demonstrate that our method is effective and robust to occlusion.

Precision-structural Design for Scanning Probe Microscopes (주사탐침현미경을 위한 정밀 구조 설계)

  • Lee, Moo-Yeon;Shim, Jae-Sool;Lee, Dong-Yeon
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.11 no.11
    • /
    • pp.4095-4099
    • /
    • 2010
  • Nano-measurement systems such as scanning probe microscopes should be protected against external disturbances. For the design of a scanning probe microscope, the external vibrations need to be characterized and the vibrational properties of the structural frame itself should be modeled. Also, the influences of the external vibration on the apparatus need to be known for its utmost precision. In this paper, the combined vibrational-characteristics of the floor and the structural frame are analyzed and experimentally investigated.

Solid-state NMR Study on Membrane Protein Structure in Biological Condition

  • Kang, Su-Jin;Lee, Bong-Jin
    • Journal of the Korean Magnetic Resonance Society
    • /
    • v.16 no.2
    • /
    • pp.103-110
    • /
    • 2012
  • Membrane proteins play a essential role in the biological systems and it is not easy to handle a membrane protein for its structural study. Solid-state NMR (ssNMR) can be a good tool to investigate the structures and dynamics of membrane proteins. In ssNMR, Magic Angle Spinning (MAS) and Cross Polarization (CP) can be utilized to reduce the line-broadening, leading to high resolution and sensitivity in the spectrum. ssNMR, if combined with other spectroscopic methods, can provide us a enough knowledge on structures and dynamics of membrane proteins in biological condition.