• 제목/요약/키워드: Pivot

검색결과 363건 처리시간 0.056초

시소 시스템을 위한 RCGA 기반의 상태피드백 제어 (RCGA-Based State Feedback Control for Seesaw Systems)

  • 오세준;소명옥;정병건;류기탁;이윤형;이상태
    • Journal of Advanced Marine Engineering and Technology
    • /
    • 제32권6호
    • /
    • pp.974-980
    • /
    • 2008
  • Generally. most of the physical systems affected by disturbance or incomplete knowledge are complex and highly nonlinear. To control under these circumstances. many researches are ongoing in modern control theory recently. But the researches need apparatuses. which can verify the controller for being not damaged the real plant. In this paper. therefore. a seesaw system is considered control system to analyze and apply the control theory. A seesaw system consists of a moving cart on the rail and seesaw frame made to demonstrate the effectiveness of the control theory. The system has balancing and positioning problems. and the driving force is applied on the DC motor of cart. but not on the pivot. The purpose of control is to maintain an equilibrium of seesaw frame in spite of an allowable disturbance. Computer simulations are given to illustrate the control performance of the proposed scheme.

시간-주파수 영역에서의 연성 충격 스펙트럼 분석을 통한 하드디스크 드라이브의 충격진동 제어 (현장개발사례: SAMSUNG HDD 'SPINPOINT V40/P40 SERIES') (Shock Vibration Control of Hard-Disk Drive Using Coupled Shock Spectrum Analysis in Time-Frequency Domain)

  • 한윤식;강성우;오동호;황태연;손영
    • 한국소음진동공학회:학술대회논문집
    • /
    • 한국소음진동공학회 2001년도 춘계학술대회논문집
    • /
    • pp.1111-1116
    • /
    • 2001
  • A transient T-F(time-frequency) signal processing technique is applied to a tilt drop and a linear shock test rigs for identification of shock characteristics of hard disk drive (HDD). The T-F technique essentially tracks the shock characteristics of pivot point response as well as head slap and lift-off phenomena. From the T-F analysis result, the shock characteristic in HDD is modeled by the two degree of freedom coupled-dynamic system, which consists of actuator arm and suspension. As shock designing tool, the maximax shock response spectrum is employed for prediction of shock performance. Finally, the shock control technique is tested with newly designed actuator arm and suspension. Experimental head slap test result shows that the shock performance is much higher with the new shockproof designed model than the current model

  • PDF

일-한 기계 번역에 있어서 한국어 술부의 생성과 평가 (Generation of Korean Predicates for Japanese-Korean Machine Translation System and its Evaluation)

  • 김정인;문경희;이종혁;이근배
    • 한국정보과학회 언어공학연구회:학술대회논문집(한글 및 한국어 정보처리)
    • /
    • 한국정보과학회언어공학연구회 1996년도 제8회 한글 및 한국어 정보처리 학술대회
    • /
    • pp.329-337
    • /
    • 1996
  • 일-한 기계 번역을 연구하는 많은 연구자들은 양국어의 문절-어절 단위의 어순 일치와 같은 구조적 유사성을 최대한 이용하기 위해 직접 번역 방식을 채택하고 있다. 그러나, 일본어와 한국어 술부간에는 대응하는 품사의 불일치 및 국부적인 어순의 불일치 등이 어려운 문제로 남아 있다. 본 논문에서는 이들 술부 표현의 불일치를 해결하기 위해 이미 제안하였던 "양상 테이블을 기반으로 한 한국어 술부의 생성 방법"에 대해 좀더 체계적인 평가를 하고자 한다. 이 방법은 술부만을 대상으로 하는 추상적이고 의미 기호적인 양상 자질(modality feature)을 테이블화(양상 테이블)하여, 양국어의 술부 표현의 피봇(pivot)으로 이용함으로써 술부 양상 표현의 효과적인 번역을 가능하게 하였다. 일본어 499 문을 대상으로 실제 술부의 번역처리를 시행해 본 결과, 약 97.7%가 자연스럽게 번역됨을 확인하였다. 특히, 술부의 생성 부분은 일본어에 의존하지 않는 양상 테이블을 도입함으로써 일-한뿐만 아니라 다른 언어로부터의 한국어 술부 생성에도 적용시킬 수 있을 것이다.

  • PDF

우리나라 기업회계원칙에 관한 고찰 (A Study on the Principle of Business Enterprises Accounting)

  • 최달수
    • 산업경영시스템학회지
    • /
    • 제2권2호
    • /
    • pp.93-103
    • /
    • 1979
  • As principles of our country's Business Enterprises Account are being developed, Customs of Business Enterprises Account are in the state of change and then Principles of that are in revision. According to systematizing contents of such a principle of Business Enterprises Account, having made an analysis and Investigation from versatile situation, I can deprive of the following conclusions from above facts. 1. The prelude of a general principle involves compulosory character like a forced law rather than a theoretical teaching of original character. 2. Because of making much of supply of account information, To make mistakes, emphasis on function of an information, on the other side, being apt to disregard control function of original account. 3. There is no such a mutual relation as theoretical systematic form among general rule, a profit-and-loss account, balance sheet and drawing principle. These rules which don't form gradual structure are prescribed respectively according to business like necessity. 4. An overall contents of account principle are regarded as principle near financial account rather than the Pivot of administration account. In the future, The whole academic world of account and business practice should become the idealistic account principle with lots of study and effort.

  • PDF

물리치료사의 환자 운반 시 작업 부하 분석에 NIOSH 들기 공식 적용: 사례연구 (Application of NIOSH Lifting Equation to Analysis of Workload for Patients Transferring by Physical Therapist: a Case Study)

  • 이인희
    • The Journal of Korean Physical Therapy
    • /
    • 제21권3호
    • /
    • pp.119-124
    • /
    • 2009
  • Purpose: The National Institute for Occupational Safety and Health (NIOSH) lifting equation (NLE) is a useful tool to ergonomically analyze a workload. The NLE has high reliability and it can assess tasks by analyzing the work process. The purpose of this case study was to try using the NLE to analyze the workload of transferring patients by physical therapists in the hospital setting. Methods: We observed a physical therapist (PT) transferring patients from a wheelchair to a tilt table and a therapeutic table in one day. Two types of patient transferring methods were evaluated; (1) the manual single person method of stand, pivot and transfer, and (2) manual two person lifting under the thigh and grasping the waist for totally dependent patients. Results: The NIOSH lifting indexes of a person grasping the waist during the manual two person lifting were 5.52~4.48 according to the patient's weight. The NIOSH lifting indexes were 3.34 and 4.48 for the tasks performed by the manual single person method. Conclusion: Because transferring patients is not done very frequently, patients transferring tasks by a PT are not included as one of the musculoskeletal disorder related risky work criteria of the Korea Ministry of Labor. But the NIOSH lifting indexes of a person grasping the waist during the manual two person lifting and the manual single person method were over the NIOSH recommended weight limit threshold.

  • PDF

편심 베어링 - 비틀림 스프링 내장형 자동벨트 긴장장치의 진동해석 (Vibration Analysis of a BEBTS(Built-in Eccentric Bearing-Torsional Spring) Type ABTU(Automatic Belt Tension Unit))

  • 최영휴;안영덕;정원지
    • 한국정밀공학회지
    • /
    • 제19권3호
    • /
    • pp.95-100
    • /
    • 2002
  • Built-in Eccentric Bearing-Torsional Spring (BEBTS) type Automatic Belt Tension Unit (ABTU) is one of typical belt tension units. The BEBTS type ABTU system frequently experiences torsional vibration about its pivot due to the variation of belt tension. However, it is very difficult to analyze the rotational (or torsional) vibration of the ABTU because the exciting moment varies according to the change of belt tension. To get over this difficulty, in this paper. the ABTU was simplified as 1-DOF translational motion model in the tangential direction. Its equation of motion was derived and solved. The time history and frequency responses were computed and examined for three of BEBTS type ABTUs which are made by different manufacturers but the tame kind.

시저스 시스템을 적용한 파사드 디자인에 관한 연구 (A Study on the Facade Design Using Scissors System)

  • 김승덕;정혜원
    • 한국공간구조학회논문집
    • /
    • 제17권4호
    • /
    • pp.133-140
    • /
    • 2017
  • Recently, the interest in the smart buildings is increasing in the architecture field. Among them, a research of facade design using a transformable system that can adjust the effect of the external environment is in progress. One of a typical example of the deployable system is a Scissors system that can change shape by using the geometric conditions of a unit member. Scissors system is a high-tech structural system which can construct the deployable plan and curved space by using the SLE (Scissors-Like Element) consisted of two Bar and Pivot. If the facade is designed by applying Scissors system, it is possible to maximize the performance and aesthetic effect of the structure by using a shape change of the line member. This paper presents a study of deployable facade design applying hybrid-typed Scissors system. A new deployable pattern of facade design is developed by combining Angulated Scissors system and tessellation pattern. Applying the deployable pattern a double skin construction method which is to add an outer wall for design, it raises three dimensional effects and can maximize the artistic essence of the change in shape upon deployment.

Vibration Analysis of HDD Actuator with Equivalent Finite Element Model of VCM Coil

  • Kim, Dong-Woohn;Lee, Jin-Koo;Park, No-Cheol;Park, Young-Pil
    • Journal of Mechanical Science and Technology
    • /
    • 제17권5호
    • /
    • pp.679-690
    • /
    • 2003
  • As the rate of increase in areal density of the HDD has accelerated, dynamic characteristics of the HDD actuator need to be improved with respect to the performance of the tracking servo and shock transmission. Therefore, it is important to analyze the vibration characteristic of the HDD actuator that consists of the VCM part, E-block and pivot bearing. In this paper, vibration modes of the HDD actuator are investigated the using finite element and experimental modal analyses methods. To develop a detailed finite element model, finite element models of each components of the actuator assembly are constructed and tuned to the results of the EMA. The VCM coil is modeled as an equivalent finite element model that has an orthotropic material property using auto-model updating program. Auto-model updating program with improved sensitivity based iterative method is applied to build a detailed finite element model using the result of the EMA. A detailed finite element model of the HDD actuator is then constructed and analyzed.

대퇴과간절흔 성형술에서 유연성 연마기를 이용한 방법 (Notchyplasty with Flexible Reamer)

  • 채인정;이광석;백종륜
    • 대한관절경학회지
    • /
    • 제1권1호
    • /
    • pp.123-127
    • /
    • 1997
  • Arthroscopic anterior cruciate ligament reconstructions using bone-patella tendon-bone have been considered the best method by which others are compared. The notchyplasty is one of the important steps of this procedure and it is emphasized recently to prevent retear of the reconstructed ACL caused by impingement. However, until now, there is controversy about adequate amount of notchyplasty. Also, it is hard to examine the adequacy of notchyplasty even in the arthroscopic field, The purpose of this paper is to describe the surgical technique of notchyplasty, using the flexible reamer and preliminary result of its operation. In this study the results of ACL reconstruction with notchyplasty which is made by us were analized from January. 1994 to December, 1995. The results were as follows: 1. The notchyplasty with flexible reamer is the method that can be obtained adequate amount of removal, perfectly smooth notchyplasty. 2. The range of motion of the affected knee joint was normal ROM after post operation 6 month. 3. In the last follow up, 2 cases were positive in anterior drawer test 4 cases were positive in Lachmann's test and 1 knee was positive in Pivot shift test 4. Average Lysholm knee scoring scale was 70 points at preoperative and 92 points at the last follow up.

  • PDF

관절경적 전방십자인대 재건술시에 골-슬개건-골과 네가닥 반건양건-박건을 이용한 방법의 비교연구 (Comparative Study of Arthroscopic ACL Reconstruction Using Bone-Patellar Tendon-Bone Versus Four-Stranded Semitendinosus-Gracilis Tendon)

  • 김진구;임영;김병직;고한석;문형태
    • 대한관절경학회지
    • /
    • 제2권2호
    • /
    • pp.107-113
    • /
    • 1998
  • This study is retrospective analysis of 31 patients treated by arthroscopically assisted ACL reconstruction, from September 1995 to September 1996. ACL reconstructions using autogenous bone patellar tendon bone (B-PT-B) were done in 18 patients, and using hamstring tendon were done in 13 patients. We used four-stranded hamstring tendon grafts and fixed the grafts using Endobutton and screw. The mean postoperative Lysholm knee score was 87.2 points in B-PT-B. group, and 89.0 points in hamstring tendon group. There were no clinically significant results between two groups in Telos test, quadriceps atrophy, Lachman test, anterior drawer test and pivot shift test, but the incidences of anterior knee pain were lower in hamstring group. Four-stranded hamstring tendon graft showed enough stability and good functional outcome similar to that of patellar tendon graft, and had an advantage of quicker return of quadriceps function and less donor site morbidity.

  • PDF