• 제목/요약/키워드: Experimental Method

검색결과 28,647건 처리시간 0.062초

전최소자승법을 이용한 강인한 모드매개변수 (Robust Modal Parameter Idnentification Using Total Least Square Method)

  • 정의봉;김준엽;김현
    • 대한기계학회논문집A
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    • 제20권3호
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    • pp.843-849
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    • 1996
  • The least square estimation is used frequently in experimental modal analysis techinque to eliminate noise signals. However, identified modal parameters are sometimes inaccurate, since the least squre estimation is sensitive to noise. In this paper, a new total least squre estimation, which is robust to noise signals, is developed and applied to experimental modal analysis technique such as Prony method and Circle Fit method. Several simulated results show that the proposed method is robuster to noise than conventional method.

Assessment of Acoustic Iterative Inverse Method for Bubble Sizing to Experimental Data

  • Choi, Bok-Kyoung;Kim, Bong-Chae;Kim, Byoung-Nam;Yoon, Suk-Wang
    • Ocean Science Journal
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    • 제41권4호
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    • pp.195-199
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    • 2006
  • Comparative study was carried out for an acoustic iterative inverse method to estimate bubble size distributions in water. Conventional bubble sizing methods consider only sound attenuation for sizing. Choi and Yoon [IEEE, 26(1), 125-130 (2001)] reported an acoustic iterative inverse method, which extracts the sound speed component from the measured sound attenuation. It can more accurately estimate the bubble size distributions in water than do the conventional methods. The estimation results of acoustic iterative inverse method were compared with other experimental data. The experimental data show good agreement with the estimation from the acoustic iterative inverse method. This iterative technique can be utilized for bubble sizing in the ocean.

마운트계의 실험적 설계변경을 위한 전달함수분리법의 개발 (Development of Transfer Function Separation Method for Experimental Dynamic Modification of Mounted System)

  • 정의봉;조영희
    • 소음진동
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    • 제7권5호
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    • pp.847-852
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    • 1997
  • Many investigations about the dynamic analysis of the structural system based on the BBA(Building Block Approach) method which predict dynamic characteristics of synthesized structures from each structure. But it is actually sometimes difficult to remove mounts from structures. In this paper, TFSM(The Transfer Function Separation Method) is developed which can predict dynamic characteristics of separated structures from the data of vibrational experiment of the synthesized structures. By combining TFSM with BBA, this paper also proposes the method which can predict dynamic characteristics of mount-modified structure without removing mounts from structures. And the proposed method is verified by the experimental data of plates.

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테이핑 요법이 노인의 무릎 통증과 관절가동범위에 미치는 영향 (Effects of a Taping Method on Pain and ROM of the Knee Joint in the Elderly)

  • 박영숙;김현정
    • 대한간호학회지
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    • 제35권2호
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    • pp.372-381
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    • 2005
  • Purpose: This study was to investigate the effects of a taping method on pain and ROM of the knee joint in the elderly. Method: The subjects were seniors registered in a senior welfare center in D city. An experimental group of 30 persons and acontrol group of 33 persons were chosen and according to the proper conditions and a knee pain score was marked from 1-5 on a Numerical Pain Rating Scale. For the experimental group, the taping method was conducted three times a week for four weeks (twelve times in all) but the control group did not receive taping.. The measuring instrument of knee pain was a numerical pain rating scale from 0 to 10 and the ROM score was the average value of three measured values with a goniometer. The data was analyzed with SPSS WIN 10.0 using an $x^2-test$, t-test, repeated measures ANOVA, and time contrast. Result: Knee joint pain was significantly decreased in the experimental group over that of the control group (p=.001). In addition, knee joint ROM of the experimental group was significantly improved over that of the control group (p=.001). Conclusion: It was proven that the taping method was effective for pain relief and increasing ROM of the knee joint in the elderly.

간호원의 의사소통방법이 정신병환자 반응에 미치는 영향에 대한 실험적 연구 (An Experimental Study on the Excellences of Nurses′ Communication Method upon Psychiatric Patient′s Response.)

  • 이평숙
    • 대한간호학회지
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    • 제4권2호
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    • pp.78-92
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    • 1974
  • It is the purpose of this study to make clear the way in which people can lead a more desirable human life, that is, to ascertain the method of achieving therapeutic change through transaction between nurses and psychiatric patients. The various problems proposed by th9 above-stated aims of study can be shown, such as: What kind of influences does the method of a nurse′s communication have upon the response of psychiatric patients? 1) What are the general methods of communication used by the nurses? 2) Are there any differences between the control group and experimental group in the patients′ "Child" response? 3) Are there any differences between the control group and experimental group in the Patients "Adult" response? 4) What is the most desirable method of communication for therapeutic change in the patients? In an effort to solve the above questions this study attempted and managed to draw a random sampling of 200 patients being accommodated in the National Mental Hospital by dividing them into two groups, experimental groups and control groups, and recording the transactions between nurses and patients. In the course of carrying,: out this study, the experimental group was interviewed by the nurses specially trained In the P.A.C theory. and the control group interviewed at random by the nurses with no special training in communication. Further, the communication between nurses and patients in a free, relaxed atmosphere was allowed only for 15 minutes, whereupon the nurses were requested to make process-recording according to her memory of nurse patient transaction. The process-recording which recorded a series ol transactions between the nurses and the patients was analyzed according to Berne and Harris′transactional Analysis Standard. Through this standard, the writer of this study examined the significance of difference to compare the transactions brought forth between the experimental group and the control group. The following is a summary of the study which the writer of this thesis undertook. Hypothesis to The method of communication which the nurses usually apply to the patients will be higher in "Parent" than in "Adult". The communication which the nurses carried out in the control group turned out to be not significant between "Adult" and "Parent" Accordingly hypothesis 1. carne to be rejected. Hypothesis 2. The patients "Adult" response will be higher in the experimental group than in the control group. According to the result of a CR examination, as the communication showed a significant difference on P〈.01 level′ hypothesis 2 became affirmative. Hypothesis 3. The patients′"Child" response will be higher in the control group than in the experimental group. Hypothesis 3 proved affirmative since it showed an significant degree on P〈.01 level according to the result of a CR examination. Hypothesis 4 "Adult" response of the patient will be higher in frequency by nurses′"Adult" stimulus than nurse′s "Parent" stimulus Chi-square examination revealed significant difference on P〈.05 level. Hypo. 4 is affirmed. The following conclusions are drawn out based on the result of this study. 1) The generally used method of communication stimulus used by nurses for patients proved to be "Adult" and "Parent" in similar proportion. 2) The group in which the nurses could increase the patients "Adult" response proved to be higher in the experimental group than in the control group. Therefore, the communication (or stimulus) which has been applied in the experimental group can be said to be possible method of achieving therapeutic change. 3) Since the patients′"Child" response were higher in the control group than in the experimental group the communication method used In the control group was suggested as the less agreeable method of achieving therapeutic change than that used in the experimental Group. 4) "Adult" response of patient was elicited in significantly greater percentage when the "Adult" stimulus was used by the nurse. Therefore the most desirable method of-communication to give therapeutic change definitely was shown to be the "Adult" stimulus. Recommendations for further studies are as follows: 1) Studies on nurses′role perception in nurse-patient relationships. 2) Studies on patients′response to the method of communication used by nurses according to variables such as sex, social status, educational background, state of health. 3) Application of T.A, method to various groups of patients. 4) Study of various methods to improve student skill in use of process recording.

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하이브리드 실험법을 이용한 TLD가 설치된 건물의 지진응답 제어 (Earthquake Response Control of a Building with a Tuned Liquid Damper Using Hybrid Experiment Method)

  • 이성경;이상현;민경원;박은천;우성식;정란;윤경조
    • 한국지진공학회:학술대회논문집
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    • 한국지진공학회 2006년도 학술발표회 논문집
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    • pp.527-534
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    • 2006
  • A real-time hybrid method, in which the experimental implementation and the numerical computation of a structure are simultaneously carried out in real-time and combined on-line, has been used as a dynamic testing technique of structure to investigate its dynamic behaviors. In this paper, an experimental hybrid method, which implements the earthquake response control of a building structure with a TLD by using only a TLD as an experimental part, is proposed and is experimentally verified through a shaking table test. In the proposed methodology, the whole building structure with a TLD is divided into the upper TLD and the lower structural parts as experimental and numerical substructures, respectively. At the moment, the control force acting between their interface is measured from the experimental TLD with shear-type load-cell which is mounted on shaking table. Shaking table vibrates the upper experimental TLD with the response calculated from the numerical substructure, which is subjected to the excitations of the measured interface control force at its top story and an earthquake input at its base. The experimental results show that the conventional method, in which both a TLD and a building model are physically manufactured and are tested, can be replaced by the proposed methodology with a simple experimental installation and a good accuracy for evaluating the control performance of a TLD.

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회전원판 근처에서 회전하는 유연디스크에 대한 실험 및 수치해석 (Experimental and Numerical Study on an Air-Stabilized Flexible Disk Rotating Close to a Rigid Rotating Disk)

  • 가드압델라솔;임윤철
    • 정보저장시스템학회논문집
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    • 제5권1호
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    • pp.19-35
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    • 2009
  • The present work is an experimental and analytical study on a flexible disk rotating close to a rigid rotating disk in open air. In the analytical study, the air flow in the gap between the flexible disk and the rigid disk is modeled using Navier-Stokes and continuity equations while the flexible disk is modeled using the linear plate theory. The flow equations are discretized using the cell centered finite volume method (FVM) and solved numerically with semi-implicit pressure-linked equations (SIMPLE algorithm). The spatial terms in the disk equation are discretized using the finite difference method (FDM) and the time integration is performed using fourth-order Runge-Kutta method. An experimental test-rig is designed to investigate the dynamics of the flexible disk when rotating close to a co-rotating, a counter-rotating and a fixed rigid disk, which works as a stabilizer. The effects of rotational speed, initial gap height and inlet-hole radius on the flexible disk displacement and its vibration amplitude are investigated experimentally for the different types of stabilizer. Finally, the analytical and experimental results are compared.

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연삭가공 표면 거칠기 기상계측 방법

  • 김현수;안국진;홍성욱
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1993년도 추계학술대회 논문집
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    • pp.345-350
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    • 1993
  • This paper presents a new method based upon the light scattering concept for on-the-machine measurement of roughness of ground surfaces. The present method utilizes fluxes of scattered lights condensed through lenses aligned along the specular direction. A theorctical analysis is preformed for the purpose of investigating the possibility of the method as well as determining the experimental condition. Experiment is also performed to show the effectiveness of the proposed method. The theoretical and experimental results show that the proposed method has a potential to identify a wide range of surface roughness and is robust enough to be useful in on-the-machine measurement of roughness of ground surfaces.

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키네시오 테이핑 방법이 만성 뇌졸중 환자의 발목관절 근긴장도, 균형 능력 및 관절가동범위에 미치는 영향 (Effect of Kinesio Taping Method on Ankle Muscle Tone, Balance Ability and Range of Motion in Chronic Stroke Patients)

  • 박영한;어영선
    • 대한물리의학회지
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    • 제16권1호
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    • pp.83-92
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    • 2021
  • PURPOSE: This study examined whether ankle joint stabilizing taping and muscle control taping influenced the ankle range of motion (ROM), muscle tone, and balance ability in chronic stroke patients. METHODS: Ten stroke patients were assigned randomly to experimental group 1 (joint stabilization taping n = 5) and experimental group 2 (Muscle control taping n = 5). After general physical therapy in both groups, ankle stabilization taping was applied to experimental group 1, and muscle control taping was applied to experimental group 2 three times a week for a total of six weeks (18 times). RESULTS: The muscle tone and stiffness of the gastrocnemius (GCM) showed significant differences between the experimental 1 and experimental 2 groups (p < .05). The Berg Balance Scale (BBS) and ROM also showed significant differences within the experimental 1 and experimental 2 groups (p < .05). The BBS and ROM also showed no significant differences between the experimental 1 and experimental 2 groups (p > .05). CONCLUSION: This study examined the muscle tone, balance, and ROM on the paraplegic side of stroke patients using kinesio taping, and the effect of the taping application method was confirmed from the preceding study. Therefore, it can decrease the paralysis side muscle tone and improve the ROM and balance ability.

선박의 파랑 중 부가저항에 대한 실험과 수치계산의 비교 연구 (Systematic Experimental and Numerical Analyses on Added Resistance in Waves)

  • 박동민;서민국;이재훈;양경규;김용환
    • 대한조선학회논문집
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    • 제51권6호
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    • pp.459-479
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    • 2014
  • This paper considers experimental and numerical studies on added resistance in waves. As the numerical methods, three different methods, strip method, Rankine panel method and Cartesian-grid method, are applied. The computational results of vertical motion response and added resistance are compared with the experimental data of Series 60($C_B=0.8$) hull, S175 containership and KVLCC2 hull. To investigate the influence of above-still water hull form, a Rankine panel method is extended to two nonlinear methods: weakly-nonlinear and weak-scatterer approaches. As nonlinear computational models, three ships are considered: original KVLCC2 hull, 'Ax-bow' and 'Leadge-bow' hulls. Two of the three models are modified hull forms of original KVLCC2 hull, aiming the reduction of added resistance. The nonlinear computational results are compared with linear results, and the improvement of computational result is discussed. As experimental approach, a series of towing-tank experiment for ship motions and added resistance on the three models (original KVLCC2 hull, 'Ax-bow' and 'Leadge-bow') are carried out. For the original KVLCC2 hull, uncertainty analysis in the measurement of vertical motion response and added resistance is performed in three waves conditions: ${\lambda}/L=0.5$, 1.1, 2.0. From the experimental results, the effects of hull form on added resistance are discussed.