• 제목/요약/키워드: objective measurement

검색결과 1,906건 처리시간 0.028초

로봇 캘리브레이션을 위한 모델 파라미터의 관측성 연구 (A Study on Observability of Model Parameters for Robot Calibration)

  • 범진환;양수상;임생기
    • 한국정밀공학회지
    • /
    • 제14권4호
    • /
    • pp.64-71
    • /
    • 1997
  • Objective of calibration is to find out the accurate kinematic relationships between robot joint angles and the position of the end-effector by estimating accurate model parameters defining the kinematic function. Estimating the model parameters requires measurement of the end-effector position at a number of different robot configurations. This paper studies the implication of measurement configurations in robot calibration. For selecting appropriate measurement configurations in robot calibration, an index is defined to measure the observability of the model parameters with respect to a set of robot configurations. It is found that, as the observability index of the selected measurement configurations increase the attribution of the position errors to the parameter errors becomes dominant while the effects of the measurement and unmodeled errors are less significant; consequently better estimation of parameter errors is expected. To demonstrate the implication of the observability measure in robot calibration, computer simulations are performed and their results are discussed.

  • PDF

주관적 수면평가와 활동기록기를 이용한 수면평가의 비교 - 정신과입원환자를 대상으로 - (Comparison between Subjective and Actigraphic Measurement of Sleep in Psychiatric Inpatients)

  • 정현강;이문수;고영훈;임세원;김승현;정인과;조숙행
    • 정신신체의학
    • /
    • 제18권1호
    • /
    • pp.30-39
    • /
    • 2010
  • 연구목적 : 임상현장에서 주로 환자나 간호사의 주관적인 수면보고에 의존하여 수면을 평가하고 있다. 본 연구에서는 주관적 수면평가와 활동기록을 이용한 수면평가를 비교하고자 한다. 방 법 : 32명의 정신과 입원 환자를 대상으로 하였고, 대상자들에게 활동기록기를 이용한 수면평가, 수면일지, 주관적인 수면의 질에 대한 시각적 증상 정도 평가, BDI, STAI를 시행하였다. 간호사도 3일 동안 한 시간마다 환자의 수면을 평가하였다. 결 과 : 환자의 보고와 활동기록기를 이용한 수면측정상 입면잠복시간에서 유의한 차이를 보였다. 환자는 간호사보다 자고 있음에도 깨어있었다고 더 많이 보고하였다. 주관적 수면평가와 활동기록 수면평가의 차이는 불안, 우울과 상관관계를 보였다. 결 론 : 주관적으로 수면의 질을 낮게 평가하는 환자일수록 활동기록기로 측정한 입면잠복시간과 더 큰 차이를 보였고, 우울, 불안 증상이 심한 환자의 수면보고는 활동기록 측정값과 큰 차이를 보였다. 이런 환자들에게 수면의 질에 대한 질문만으로는 정확한 수면평가가 어려우므로 객관적인 수면평가가 필요하겠다.

  • PDF

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

  • 이지연;박재옥
    • 한국의류학회지
    • /
    • 제27권11호
    • /
    • 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.

다구찌의 피드백 제어 시스템에 관한 연구 (A Study on Taguchi's Feed-back Control System)

  • 김지훈;정해성;김재주
    • 품질경영학회지
    • /
    • 제26권3호
    • /
    • pp.60-70
    • /
    • 1998
  • When driving the expected loss generated by the quality deviation, Taguchi(1991b) assumed that an objective characteristic has the uniform distribution in its control limit. But it is reasonable to assume that an objective characteristic has the normal distribution than the uniform distribution. Since the triangular distribution is similar to the normal distribution and easy to handle as well, in this article, we first find the optimum measurement interval and the optimum control limit under the triangular distribution. Under the normal assumption, the modified method is compared to Taguchi's. Secondly we find the numerical value solution of the optimum measurement interval and the optimum control limit under the normal distribution.

  • PDF

Evaluation of Fabric Pilling Using Hybrid Imaging Methods

  • Kim Sung-Min;Park Chang-Kyu
    • Fibers and Polymers
    • /
    • 제7권1호
    • /
    • pp.57-61
    • /
    • 2006
  • A study has been made on the quantification and evaluation of fabric pilling using two-dimensional and three-dimensional hybrid imaging methods. Two-dimensional imaging method was good for some samples while three-dimensional measurement method for others, according to the properties of their base fabric. Various image processing techniques as well as three-dimensional data processing algorithms were applied for the extraction of pills from measured data and a series of shape parameters have been defined for the objective evaluation of fabric pilling. An evaluation criterion that is compatible with the conventional evaluation method has been proposed by applying the new evaluation method to the current photographic standards.

에어컨 실내기에서 발생하는 충격 소음원의 위치 추정 (Source localization of impact noise on an indoor unit of air-conditioner)

  • 최영철;김양한;이종구;김구영
    • 한국소음진동공학회:학술대회논문집
    • /
    • 한국소음진동공학회 2003년도 추계학술대회논문집
    • /
    • pp.324-329
    • /
    • 2003
  • An air-conditioner has various noise sources such as cooling fan noise, pumping noise, flow noise and impact noise. Among these, impact noise is the most unpleasant source. This is because the noise is produced in indoor unit of air-conditioner. To control the noise source effectively, first we must identify the noise sources. When we identify impact noise source, the measurement have to be carried out simultaneously. So we use beamforming method that requires less measurement points than intensity method and acoustic holography. The objective of this paper is to estimate the location of impact source. This objective can be achieved by using minimum variance cepstrum that is able to detect impulse embedded in noise. In this study, modified beamforming method based on cepstrum domain is proposed. Then this method applied to air-conditioner noise sources which produce impact noise.

  • PDF

바람통로 계획을 위한 기후생태적 우선지역 분석 및 설정 방법 - 성남 판교지역을 중심으로 - (Methodology of Climate-Ecological Priority Area Analysis for Air Corridor Planning - In the Case of Pan-Gyo Area -)

  • 송영배
    • 한국조경학회지
    • /
    • 제31권3호
    • /
    • pp.58-73
    • /
    • 2003
  • It is well known that urban environment affects climate, as we can see in the quality of bio-climate. However, climate has not been recognised properly in the urban planning process. The role it flays needs to be examined for better urban environment. The main objective of this study is to investigate the climate-ecological priority area which produces cold fresh air and thermal induced wind circulation between rural and urban areas. The objective is also to improve the quality of bio-climate and wind circulation at blocked urban areas. This paper uses the measurement and analysis method of wind direction and wind speed in order to investigate the climate-ecological priority area and cold fresh air corridor. In this study, local climate conditions i.e. wind speed, wind direction, temperature, humidity etc., were measured at nine fields and analyzed. On the basis of the climate measurement, the climate ecological priority areas were delineated; These will be assigned as climate-ecological conservation areas.

A STUDY ON THE IMPROVEMENT OF POST-EVALUATION ITEM FOR PERFORMANCE MEASUREMENT IN THE BUILDING CONSTRUCTION

  • Lee, Eun-Ji;Ha, Hee-Yoon;Ko, Hyun;Kim, Jae-won;Kim, Jae-Jun
    • 국제학술발표논문집
    • /
    • The 2th International Conference on Construction Engineering and Project Management
    • /
    • pp.407-416
    • /
    • 2007
  • The construction industry in South Korea is experiencing great changes: it is becoming developed on a larger scale, specialized to a high degree and rapidly incorporating with other industries. This development has resulted in higher demand of construction industry. Accordingly, the transparency and an objective method of evaluation in the process of projects in the construction industry are gaining more importance. Clients' and customers' needs also require more specific objective evaluation to find whether their projects are successfully performed or not. This study aims to discuss problems on the current post-evaluation items including the qualitative item analysis such as customer satisfaction. Moreover, this paper suggests the improved ways in which enable the application of the effective evaluation system to the construction industry.

  • PDF

Digital Image Quality Assessment Based on Standard Normal Deviation

  • Park, Hyung-Ju;Har, Dong-Hwan
    • International Journal of Contents
    • /
    • 제11권2호
    • /
    • pp.20-30
    • /
    • 2015
  • We propose a new method that specifies objective image quality factors by evaluating an image quality measurement model using random images. In other words, No-Reference variables are used to evaluate the quality of an original image without using any reference for comparison. 1000 portrait images were collected from a web gallery with votes constituting over 30 recommendation values. The bottom-up data collecting process was used to calculate the following image quality factors: total range, average, standard deviation, normalized distribution, z-score, preference percentage. A final grade is awarded out of 100 points, and this method ranks and grades the final estimated image quality preference in terms of total image quality factors. The results of the proposed image quality evaluation model consist of the specific dynamic range, skin tone R, G, B, L, A, B, and RSC contrast. We can present the total for the expected preference points as the average of the objective image qualities. Our proposed image quality evaluation model can measure the preferences for an actual image using a statistical analysis. The results indicate that this is a practical image quality measurement model that can extract a subject's preferred image quality.

KBSI-HVEM 대물렌즈의 구면수차 계수 측정 (Measurement of Spherical Aberration Coefficient of the Objective Lens in KBSI-HVEM)

  • 김영민;심효식;김윤중
    • Applied Microscopy
    • /
    • 제37권2호
    • /
    • pp.111-121
    • /
    • 2007
  • Diffractogram 법을 이용하여 한국기초과학지원연구원에 설치된 초고전압 투과전자현미경(KBSI-HVEM)의 대물렌즈에 대한 구면수차 계수와 분해능을 측정하였다. 측정 정밀도 향상을 위해 획득한 diffractoram을 디지털 처리하였고 각 intensity 분포 그래프를 graphical curve fitting으로 정밀하게 분리하였다. 정밀 측정을 위한 실험적 고려 사항들을 고찰하였고 최적 실험 조건 도출을 위한 방안들을 본 실험을 통해 제안하였다. 실험적으로 측정된 대물렌즈의 구면수차 계수는 $2.628{\pm}0.04\;mm$였으며 이 값은 제조사에서 대물렌즈 설계 시 제안한 $C_s=2.61\;mm$와 거의 일치하는 값이었다.