• Title/Summary/Keyword: standard measurement methods

Search Result 870, Processing Time 0.026 seconds

A Suggestion on Thermal Distributed Function for Thermal Stress Analysis in Mass Concrete (매스콘크리트 온도응력해석을 위한 온도분포함수 제안)

  • Kim Hyeon Kyeom;Kim Seung Ik;Han Jae Ho;Lee Chang Soo
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 2004.05a
    • /
    • pp.136-139
    • /
    • 2004
  • The domestic concrete standard specification(l999) reports roughly about heat transfer analysis and thermal stress analysis for mass concrete. Engineers cannot but choice after all numerical method such FEM, FDM to escape review. It seems to us that the specification is room for reconsideration because above methods are vary expensive and without popularity. This study suggests thermal distributed function in mass concrete. The function consists of two independent variables, curing time and depth. It's results have been tested a sensitivity for unit cement content, form condition, curing condition, and shape(depth, width). Results of the function are made a comparison with analytical values of MIDAS/CIVIL and a few measurement values. The researchers could meet with coherent and good results for variable cases.

  • PDF

Development of an Air Pollution Monitoring Network Design Method Based on Regional Representativeness and Pollution Damage Impact (地域代表性과 汚染被害를 考慮한 大氣汚染 測定網 配置技法의 開發에 關한 硏究)

  • 김태형;김정욱
    • Journal of Korean Society for Atmospheric Environment
    • /
    • v.3 no.1
    • /
    • pp.47-54
    • /
    • 1987
  • A new method for designing air pollution monitoring newtork is presented in this study. In this method, the magnitudes and the correlation coefficients of predicted concentrations in each grid points are examined and the monitoring stations are assigned to those stations which cover the damage cost the most. This method was applied to the Ulsan-Onsan Industrial Complex. This method turned out to be much more efficient than the method of TM coordinates and the method of concentric circles prescribed in the Standard Methods for Pollution Measurement as well as the existing monitoring system established in the area. The 21 stations selected by the method of TM coordinates could cover only 64.4% of the damage cost in the area, the 16 stations by the method of concentric circles 72.1%, and the existing 21 stations 67.8%, while 11 stations were enough to cover 90% of the damage cost in the area with this method. It also was found that this method required only 24 stations to cover the entire area.

  • PDF

Study on Applying GPS Positioning Technique to Cannon Laying (GPS 측위기술의 포 방열 적용 연구)

  • 조정호;박종욱;박필호;임형철;최만수;권영철
    • Journal of the Korea Institute of Military Science and Technology
    • /
    • v.4 no.2
    • /
    • pp.52-59
    • /
    • 2001
  • In this paper, we have proposed a capability of applying Global Positioning System(GPS) to cannon laying. High precision GPS positioning can be used for measuring precise positions and angles. Therefore, we have tested on applying GPS positioning technique to measurement of positions and angles, which related to cannon laying. First of all, we have determined a GPS reference position using various positioning methods. Then we have carried out several tests that are process of taking corner angles between neighboring two vectors. Each vector can be calculated by post/real time positioning of two GPS antennas placed on the both ends of the howitzer. The Comer Angles from Post processing(CAP) are compared with the other Corner Angles from Real time positioning(CAR). As the results, we have an agreement between CAP and CAR within 0.25 mil average, 0.29 mil standard deviation. Finally, we have discussed about the capabilities and problems in artillery arrangement using GPS.

  • PDF

A Method for Measuring the Difficulty of Music Scores

  • Song, Yang-Eui;Lee, Yong Kyu
    • Journal of the Korea Society of Computer and Information
    • /
    • v.21 no.4
    • /
    • pp.39-46
    • /
    • 2016
  • While the difficulty of the music can be classified by a variety of standard, conventional methods are classified by the subjective judgment based on the experience of many musicians or conductors. Music score is difficult to evaluate as there is no quantitative criterion to determine the degree of difficulty. In this paper, we propose a new classification method for determining the degree of difficulty of the music. In order to determine the degree of difficulty, we convert the score, which is expressed as a traditional music score, into electronic music sheet. Moreover, we calculate information about the elements needed to play sheet music by distance of notes, tempo, and quantifying the ease of interpretation. Calculating a degree of difficulty of the entire music via the numerical data, we suggest the difficulty evaluation of the score, and show the difficulty of music through experiments.

Complex Modal Testing of Asymmetric Rotors Using Magnetic Exciter Equipped with Hall Sensors

  • Lee, Chong-Won;Kim, Si-Kyoung
    • Journal of Mechanical Science and Technology
    • /
    • v.15 no.7
    • /
    • pp.866-875
    • /
    • 2001
  • The complex modal testing methods developed for asymmetric rotors are briefly discussed and their performances are experimentally evaluated. For the experiments, a laboratory test rotor is excited by using a newly developed, cost effective magnetic exciter equipped with Hall sensors, which measure the excitation forces. It is concluded that the exciter system is characterized by a wide bandwidth and a high resolution for both the excitation and force measurement, and that the one-exciter/two-sensor technique for complex modal testing of asymmetric rotors is superior to the standard two-exciter/two-sensor technique in terms of practicality and realization.

  • PDF

A Study on the Consumer Knowledge Measurement of Apparel Product (의류 상품에 대한 소비자 지식의 척도에 관한 연구)

  • 이지연;박재옥
    • Journal of the Korean Society of Clothing and Textiles
    • /
    • v.27 no.11
    • /
    • pp.1307-1317
    • /
    • 2003
  • The level of consumer knowledge has been gradually increased with the growth of living standard of consumer and the development of communication technology. The purpose of this study was to investigate the structure and measure of consumer knowledge and to find out relationship between objective knowledge and subjective knowledge. The subjects of this study were female adults from theirs twenties to theirs forties who lived in Seoul, Kyunggi or Incheon areas and Quota sampling method was used age and areas. The data were obtained from 603 questionnaires. Data were statistically analyzed using SPSS 10 and major statistical methods are mean, frequency, Pearson correlation coefficient, and Cronbach's $\alpha$ coefficient. The results are as follows: 1. Objective knowledge consisted of the product knowledge, brand knowledge, purchase knowledge and usage knowledge, and subjective knowledge consisted of experience and self-evaluation knowledge. 2. Consumer knowledge was related to the subjective knowledge and objective knowledge. But, there was relatively a low relationship between subjective knowledge and objective knowledge of apparel.

Measurement and Analysis of Adaptation Luminance in the Threshold Zone of the Road Tunnel (도로터널의 경계부 순응휘도 측정 및 분석)

  • Han, Jong-Sung;Lee, Min-Wook;Kim, Hoon
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
    • /
    • v.26 no.1
    • /
    • pp.1-7
    • /
    • 2012
  • As the standard lighting required in the threshold zone of a road tunnel is determined by the enough contrast. Lighting design, therefore, must be determined by the calculation method of threshold luminance based on the adaptation luminance of the driver approaching the tunnel. The veiling luminance and the luminance in the access zone were measured at different time and in different weather using the veiling luminance method, a kind of perceived contrast methods, and the L20 method when the range of vision was 20 degrees. On the basis of the measured data each threshold luminance was calculated and its results were analyzed.

A Study on the Positioning Accuracy and table Deflection by Load (하중에 의한 위치결정오차와 테이블 처짐에 관한 연구)

  • 전언찬
    • Journal of the Korean Society of Manufacturing Technology Engineers
    • /
    • v.8 no.6
    • /
    • pp.98-104
    • /
    • 1999
  • As the accuracy of manufactured goods needed high accuracy processing has made the efficiency of NC and measurement technology development, the innovation of machine tools has influence the development of the semi-conductor and optical technology. The movement errors can be expressed in terms of yaw, roll an pitch etc. In the case of expanding the error range, static, dynamic and servo gain errors can be included. Machining center might have twenty-one movement errs including three types of joint errors. Those errors have been measured on the condition of just loading of standard table. Regarding these measuring methods, the mechanical compliance of the structure has not been considered. In this paper, therefor, the influences of the additional load on the positioning accuracy are investigated. The results and the techniques proposed in this study can be considered very effective and useful to compensate more correctly the positioning motion.

  • PDF

수중운동의 표적추적성능 해석과 제어기 설계

  • 윤강섭;이만형
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • 1995.04b
    • /
    • pp.330-335
    • /
    • 1995
  • The actuator's response delay, disturbance and measurement noise can often cause a significant error in the target tracking of an underwater vehicle. The first purpose of this paper is error analysis about motion of an underwater vehicle when the closed loop system has actuator and disturbance and noise. The underwater vehicle is simulated for cases of various disturbances. The second purpose is robust controller design for the underwater vehicle with parameter uncertainty. So, two robust control methods are applied for the underwater vehicle. One is standard $H_{\infty}$ control, and the other is time-varying sliding mode control with modified saturation function. Suboptimal design parameters for $H_{\infty}$ control, and design parameters for time-varying switching surfaces are provided Simulations for the two controllers are carried out and their performances are analyzed.lyzed.

  • PDF

Field Comparison of Different Types of Sea-Bed Installed Directional Wave Gauges

  • Nagai, Toshihiko;Hashimoto, Noriaki;Lohrmann, Atle;Mitsui, Masao;Konashi, Shoichiro
    • Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
    • /
    • 2003.08a
    • /
    • pp.35-43
    • /
    • 2003
  • Methods for measuring wave height and direction varies throughout the world, depending on wave climate and local traditions. In Japan, bottom mounted systems have long been the standard fur coastal areas with water depth less than 50m, and extensive studies in the 1980s and 1990s refined the systems to a level where the full wave directional spectrum could be measured. (omitted)

  • PDF