• Title/Summary/Keyword: Correlation identification

Search Result 689, Processing Time 0.033 seconds

Chatter Monitoring of Milling Process using Spindle Displacement Signal (주축 변위 신호를 이용한 밀링가공의 채터 감시)

  • Chang, Hun-Keun;Kim, Il-Hae;Jang, Dong-Young
    • Transactions of the Korean Society of Machine Tool Engineers
    • /
    • v.16 no.6
    • /
    • pp.140-145
    • /
    • 2007
  • To improve productivity of a metal cutting process, it is required to monitor machining stability in real time. Since cutting environment is harsh against sensing conditions due to vibration, chip, and cutting fluid, etc., it is necessary to develop a robust and reliable sensing system for the practical application. In this work, a chatter monitoring system was developed and its effectiveness was proved. Spindle displacement caused by cutting was selected as a main monitoring parameter. A cylindrical capacitive displacement sensor was adopted. Chatter frequencies were identified through modal analysis. To quantify chatter vibrations, chatter correlation coefficient was introduced. The identification of the monitoring system showed a good agreement with the result of experiment.

Comparisons of Utility of Various Speech Intelligibility Evaluations of Adults with Hearing Impairment (청각장애 성인의 말명료도 평가방법의 비교)

  • Do, Yeon-Ji;Kim, Soo-Jin
    • Speech Sciences
    • /
    • v.11 no.4
    • /
    • pp.173-184
    • /
    • 2004
  • This study aims to discuss the test methodologies that evaluate the speech intelligibility of hearing-impaired adults using various contexts. Seven adults with severe hearing loss participated in the experiment. The context of the speech intelligibility consists of 77 pairs of one-syllable words with phonemic contrasts, 30 two-syllable words and the list of each 12 and 10 sentences. The speech intelligibility of various contexts had significant correlation, and both one-syllable words with phonemic contrasts and the sentence 1 had higher correlation than other tests. The one-syllable words with phonemic contrasts took longer to test than others, and it demanded more effort to select the pair of words. However, from the point of view of the identification of segmental difficulties, the one-syllable words with phonemic contrasts that reflected segmental factors contributing to the intelligibility was useful.

  • PDF

Delays and its Analysis: Indian Residential Construction Projects

  • Metha, Rakesh L.;Gaikwad, Suraj V.
    • Journal of Construction Engineering and Project Management
    • /
    • v.7 no.4
    • /
    • pp.20-28
    • /
    • 2017
  • In almost every construction project, delay is an inevitable yet controllable phenomenon. The Indian construction industry encounters an enormous amount of delays in projects. Delay affects both time and money in the forms of schedule and cost overruns, respectively. Due to impressive and dynamic growth in the Indian construction sector, planned efforts are essential to limit these undesirable delays. On account of the surge in the rate of residential building construction, the task of identification and analysis of the delays in residential projects in India has been attempted by the authors. A questionnaire survey was conducted involving 100 stakeholders. Further analysis included an Importance Index to rank the identified delays, Principle Component Analysis for advanced statistical analysis, and Correlation Analysis to check the extent of agreement amongst stakeholders. Conclusions drawn with reference to the analysed data eventually reflected finance-related issues, as well as labour related problems as the dominating causes of delays. The aim of the research is to provide insight to the construction stakeholders and researchers, on an international scale, with the obtained results.

Object Tracking Algorithm using Feature Map based on Siamese Network (Siamese Network의 특징맵을 이용한 객체 추적 알고리즘)

  • Lim, Su-Chang;Park, Sung-Wook;Kim, Jong-Chan;Ryu, Chang-Su
    • Journal of Korea Multimedia Society
    • /
    • v.24 no.6
    • /
    • pp.796-804
    • /
    • 2021
  • In computer vision, visual tracking method addresses the problem of localizing an specific object in video sequence according to the bounding box. In this paper, we propose a tracking method by introducing the feature correlation comparison into the siamese network to increase its matching identification. We propose a way to compute location of object to improve matching performance by a correlation operation, which locates parts for solving the searching problem. The higher layer in the network can extract a lot of object information. The lower layer has many location information. To reduce error rate of the object center point, we built a siamese network that extracts the distribution and location information of target objects. As a result of the experiment, the average center error rate was less than 25%.

A Study on Angular Correlation between Hallux Valgus and 1st MPJ Dorsi-flexion according to Work Type and Age of Woman (여성의 근무형태와 연령에 따른 무지 외반각도와 제1 중족족지관절 운동한계각도의 상관관계에 대한 연구)

  • Choi, Geun-Hyung;Park, Kwang-Young;Byun, Sang-Joon;Park, Seung-Hwan
    • The Journal of Korean Physical Therapy
    • /
    • v.23 no.5
    • /
    • pp.57-63
    • /
    • 2011
  • Purpose: The aim of this research is to determine whether there is a significant correlation between the angle of the hallux valgus and dorsi-flexion of the 1st metatarsophalangeal joint (1st MPJ) as a physical factor that has a significant influence on healthy human walking. Methods: The subjects of this research were 65 female adults (130 feet) and the methods used included recording of real measurements and conducting a questionnaire. The acquired data is analyzed by the 'Simple Pearson Correlation Analysis' and 'Repeated Measures Analysis' methods. Results: The research result shows that the left area of -0.74706 and the right area of -0.76 have a relatively high negative correlation (p<0.00). Also, after conducting the 'Repeated Measures Analysis of Variance' of the angles of the hallux valgus and dorsi-flexion of the 1st metatarsophalangeal joint (1st MPJ), the result also shows that the left and right areas of -0.75 have a relatively high negative correlation. Conclusion: The present study was performed for the identification of a significant correlation between the angle of the hallux valgus and dorsi-flexion of the 1st MPJ. From the results of this study, we confirmed that there is a clear tendency for the average distribution rates of Hallux Valgus and Hallux Rigidus (Hallux Limitus) of women to show a higher increase in proportion to age.

Output-Only System Identification and Model Updating for Performance Evaluation of Tall Buildings (초고층건물의 성능평가를 위한 응답의존 시스템판별 및 모델향상)

  • Cho, Soon-Ho
    • Journal of the Earthquake Engineering Society of Korea
    • /
    • v.12 no.4
    • /
    • pp.19-33
    • /
    • 2008
  • Dynamic response measurements from natural excitation were carried out for 25- and 42-story buildings to evaluate their inherent properties, such as natural frequencies, mode shapes and damping ratios. Both are reinforced concrete buildings adopting a core wall, or with shear walls as the major lateral force resisting system, but frames are added in the plan or elevation. In particular, shear walls in a 25-story building are converted to frames from the 4th floor level downwards while maintaining a core wall throughout, resulting in a fairly complex structure. Due to this, along with similar stiffness characteristics in the principal directions, significantly coupled and closely spaced modes of motion are expected in this building, making identification rather difficult. By using various state-of-the-art system identification methods, the modal parameters are extracted, and the results are then compared. Three frequency-domain and four time-domain based operational modal identification methods are considered. Overall, all natural frequencies and damping ratios estimated from the different identification methods showed a greater consistency for both buildings, while mode shapes exhibited some degree of discrepancy, varying from method to method. On the other hand, in comparison with analysis results obtained using the initial finite element(FE) models, test results exhibited a significant difference of about doubled frequencies, at least for the three lower modes in both buildings. To improve the correlation between test and analysis, a few manual schemes of FE model updating based on plausible reasons have been applied, and acceptable results are obtained. The advantages and disadvantages of each identification method used are addressed, and some difficulties that might arise from the updating of FE models, including automatic procedures, for such large structures are carefully discussed.

A study about the relationship between mouth-odor survey and self awareness (구취의 객관적 수치와 주관적 인식 간의 관계 조사)

  • Kim, Min-Young;Lee, Hye-Jin
    • Journal of Korean society of Dental Hygiene
    • /
    • v.8 no.2
    • /
    • pp.13-22
    • /
    • 2008
  • The purpose of this study is to analyze the correlation between cause and the element of mouth odor through measurement and identification of mouth odor and is to apply to effective method for elimination of halitosis, Subjects were 150 people who visited Dong Pusan College and lived in Pusan Cross-sectional survey was used and mouth odor was measured by Oralchroma. Oral examination proceeded with status of tongue plaque distribution and calculus index, Statistical analysis was performed with SPSS version 13.0 for window Among 150 people, 67.3% subjects thought they had halitosis, 89.3% people felt that their mouth odor were the severest as soon as wake-up, Tongue was serious place for halitosis by 53.3% subjects Methylmercaptan and dimethyl sulfide showed the highest correlation by 0.549 index score, Moreover, methyl mercaptan was observed the correlation with brushing time in 0.190 index score and with food intake in 0.177(P<0.05). In conclusion, brushing time and food intake were correlated with mouth odor.

  • PDF

Validity of Self-administered Semiquantitative Food Frequency Questionnaire by Conditions of One Portion Size (식품섭취빈도조사법의 1회 섭취분량 제시여건에 따른 정확도에 관한 연구)

  • 김미자;김영옥;김석일
    • Korean Journal of Community Nutrition
    • /
    • v.3 no.2
    • /
    • pp.273-280
    • /
    • 1998
  • This study was designed to estimate the improvement of Validity for food frequency questionnaire(FFQ) by offering multiple choice portion size in developing a questionnaire. Validity of the two methods(food frequency questionnaire I=FFQ I & Food frequency questionnaire II=FFQ II) was tested in comparison with reference method of the 7-day weighed record(7DWR). Dietary consumption data of the three methods(FFQ I, FFQ II & 7DWR) were collected from 101 female university students for the analysis. Validity was measured in two categories : One was the nutrient intake value from the three methods, the other was the identification of between individual variation within the group. Spearman's rank order correlation test and distribution graphs were used for the analysis. The result showed that individual intake value of the FFQII was closer to that of the 7DWR than that of the FFQ I.Spearman's rank order correlation between the FFQII and the 7DWR did not show any improved correlation. The distribution graphs of nutrient intake derived from both the FFQ I and the FFQII were different from that of the 7DWR. Therefore, it could be suggested that single one portion size food frequency questionnaire is an equally efficient method as a multiple choice food frequency questionnaire to be adopted in epidemiologic studies.

  • PDF

Correlation between Crowding and Binocular Rivalry depending on eccentricity (과밀 효과와 양안 경합의 이심률별 상관관계)

  • Kim, Sang-Rae;Chong, Sang-Chul
    • Korean Journal of Cognitive Science
    • /
    • v.21 no.2
    • /
    • pp.233-251
    • /
    • 2010
  • Crowding effect is the impairment of peripheral object identification due to nearby objects. Binocular rivalry is a phenomenon in which perception alternates between two different objects presented separately to each eye. The purpose of this study was to investigate the correlation between these two phenomena. We measured the magnitudes of visibility index of these two effects at 8 different locations of 3 different eccentricities (2, 5, and $10^{\circ}$). Significant positive correlation between the two measurements was found only near the fovea ($2^{\circ}$). Our study is the demonstration to show relationship between crowding and binocular rivalry.

  • PDF

The Correlation of VOT and f0 In the Perception of Korean Obstruents (한국어 장애음 지각에서의 VOT와 F0의 상관 관계)

  • Kim Midam
    • Proceedings of the KSPS conference
    • /
    • 2003.10a
    • /
    • pp.163-167
    • /
    • 2003
  • The present thesis examines the correlation of VOT and F0 in the three-way distinction of Korean obstruents, conducting production and perception tests. In the production test, one female native speaker of Korean with a Seoul dialect (the author) recorded 15 repetitions of a monosyllabic word list including /ka, kha, k*a, pa, pha, p*a, ta, tha, t*a, ca, cha, c*a/ in random order, VOT and F0 of the following vowels were measured, and the result was significant for the three-way distinction with a strong correlation between VOT and F0, and also in the VOT-F0 plot, no overlapping among the domains was observed. As for the perception test, I manipulated the data recorded in the production test, heightening or lowering their F0 values. In all, 14 subjects (seven males and seven females) participated in the identification test. The result was as follows: the fortis stimuli were not influenced by F0 changes, and the VOT and F0 values at the lenis-aspirated boundary were negatively correlated. From these results I concluded the following: 1) VOT and F0 can distinguish the three domains of Korean obstruents without overlapping; 2) the fortis perception does not need F0 as its acoustic cue; and 3) VOT and F0 in the distinction between the lenis and aspirated are in the phonetic trading relation[2].

  • PDF