• 제목/요약/키워드: reverse difference

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NURBS를 이용한 캠 기구의 역설계에 관한 연구 (A Study on Reverse Design of Cam Mechanism using NURBS)

  • 김상진;신중호;김대원;윤호업
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2002년도 추계학술대회 논문집
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    • pp.920-924
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    • 2002
  • This paper presents the reverse design of a cam mechanism using NURBS(Nonuniform Rational B-spline curve). Cam is very difficult to make the accurate shape on the design and the manufacture. Because the cam shape is commonly made in order to move in special functions. The reverse design can be used to check accuracy between the designed data and the manufactured data of the cam shape and also reproduce the cam without the design data. The reverse design procedures consist of motion analysis and curve fitting. The motion analysis is used the central difference method and the relative velocity method to find the displacement and velocity. The curve fitting is used NURBS to develope the whole curve. The central difference method is derived in the 3 dimensional space.

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수정된 리버스 식스 테이핑 적용이 편평족의 균형과 보행에 미치는 영향 - 사전연구 (The Effect of Modified Reverse-Six Taping on the Balance and Gait Performance in Pes Planus - Pilot study)

  • 양성화;신영일;이준용
    • 대한정형도수물리치료학회지
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    • 제22권1호
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    • pp.35-41
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    • 2016
  • Background: The purpose of this study was to investigate the effect of modified reverse-six taping on the balance and gait performance in Pes Planus. Methods: A total of twelve subjects (4 males, 8 females) in Pes Planus participated in this study. Navicular drop test was used to evaluate Pes Planus. Balance performance(anterior-posterior; A-P, medial-lateral; M-L), overall) was evaluated using the Biodex balance system in two difference condition(no-taping, with reverse-six taping). Gait performance (cadence, velocity) was evaluated using GAITRite System in two difference condition (no-taping, with reverse-six taping). Results: There were significant improvements of A-P and overall in the balance performance after using reverse-six taping (p<.05). there was no significant improvements of M-L balance performance. and, there were no statistical difference of cadence and velocity in the gait performance after using reverse-six taping. Conclusions: This study found that modified reverse-six taping in Pes Planus was improve the balance performance. but dose not affect the gait performance.

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Remote sensing images and interpretation for 'Reverse Difference' phenomenon of the marine sediments At the CaMau tongue (extreme South Vietnam - Mekong Basin)

  • 황강수;권승준;김용일
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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    • pp.682-686
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    • 2003
  • This paper is concerned with 'reverse difference' of marine sediments at the Camau tongue in the extreme south of Vietnam. We demonstrate the importance of remote sensing in geomorphology and marine geological application, using only visual evaluation and some data-processing techniques. In this paper, about 10,000 km$^2$ of the territorial water in the extreme south of Vietnam is being studied. We show that form and behavior of Mekong and its branch can be determined by visually interpreting remote sensing images and using ERDAS IMAGE 8.5 software. Besides, the 'reverse difference' phenomenon is explained by flows of Mekong river and its branches.

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일부 대학생의 척추 측만에 영향을 미치는 요인 분석 (An Analysis of Factors that Affect Spinal Scoliosis of College Students)

  • 황현숙
    • PNF and Movement
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    • 제7권2호
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    • pp.1-10
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    • 2009
  • This research measures the conditions of spinal scoliosis of college students and analyses the factors that affect spinal scoliosis. From September 15, 2008 to October 30, 2008, the study was conducted with 142 C College students and measured the degrees of spinal scoliosis. The analysis was evaluated according to the Pneumex Analysis program. The collected data was compiled into statistics using the SPSS PC+ 12.0 program. The results were as follows: 1. It appeared that in the cases of C curve, reverse C curve, S curve, and the normal, there was a statistical significance(p=.010) between the conditions of spinal scoliosis of the two genders. 2. It appeared that the comparison among the three groups according to the characteristics of the subjects showed a statistical significance in spinal length(p=.000) in the C curve group, age(p=.019) and spinal length(p=.004) in the reverse C curve group, and spinal length (p=.035), difference in apparent leg length(p=.019), and difference in true leg length(p=.012) in the S curve group. 3. It appeared that in the normal group without spinal scoliosis, the results of comparing the differences in apparent true leg length and spinal length according to the characteristics of the subjects showed a statistical significance in spinal length and gender(p=.000), age (p=.008), height(p=.000), and whether or not there was a regular exercise over once per week(p=.001). 4. On the correlations between C curve, reverse C curve, and S curve and differences in apparent true leg length and spinal length, it appeared that: (a) As the difference in apparent leg length gets bigger the difference in true leg length gets big in C curve(r=.551, p=.000). (b) As the difference in apparent leg length gets bigger the difference in true leg length gets big in reverse C curve(r=.511, p=.006). (c) There is no correlation in S curve.

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정보보호 투자와 침해사고의 인과관계에 대한 실증분석 (Information Security Investment and Security Breach: Empirical Study on the Reverse Causality)

  • 신일순;장원창;박희영
    • 정보보호학회논문지
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    • 제23권6호
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    • pp.1207-1217
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    • 2013
  • 본 연구는 2010년 한국인터넷진흥원에서 조사한 "기업의 정보보호 실태조사"의 원자료를 패널데이터로 재구성하여 정보보호 투자와 침해사고의 인과관계를 분석하였다. 이중차분법을 이용하여 분석한 실증결과는 다음과 같다. 첫째, 정보보호투자가 침해사고를 줄인다는 통상적인 인과관계에 대해서는 유의미한 실증적인 근거를 발견하기 어려웠던 반면, 역의 인과관계, 즉 침해사고가 많은 기업이 정보보호 투자를 증가시킨다는 가설은 유의미하게 데이터에 의해 입증되는 것으로 나타났다. 둘째, 정보보호에 매우 민감하기 때문에 다른 업종에 비해 과감한 사전적인 투자를 수행하는 것으로 인식되고 있는 금융/보험업의 경우, 실증분석에 따르면 오히려 침해사고의 발생에 따라 사후적으로 정보보호 투자를 수행하고 있는 대표적인 업종으로 나타났다.

Reverse Total Shoulder Arthroplasty in the Massive Rotator Cuff Tear

  • Jeong, Jin Young;Cha, Hong Eun
    • Clinics in Shoulder and Elbow
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    • 제17권3호
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    • pp.145-150
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    • 2014
  • In the patients of retracted massive rotator cuff tears, there are much of difficulty to functional recovery and pain relief. Nevertheless the development of treatment, there are still debates of the best treatments in the massive rotator cuff tears. Recenlty various of treatments are introduced; these are acromioplasty with debridement, biceps tenotomy, great tuberoplasty with biceps tenotomy, partial repair, mini-open rotator cuff repair, arthroscopic rotator cuff repair, soft tissue augmentation, tendon transfer, flap, hemiarthroplasty, and reverse total shoulder arthroplasty. That there is no difference of result for reverse total shoulder arthroplasty between patients who have massive rotator cuff tear without arthritis and patients who have cuff tear arthropathy. Reverse total shoulder arthroplasty is one of reliable and successful treatment options for massive rotator cuff tear. Especially it is more effective for patients who have a pseudoparalysis.

고주파 유도가열을 이용한 열간 파이프 벤딩 공정 설계 (Process Design of the Hot Pipe Bending Process Using High Frequency Induction Heating)

  • 류경희;이동주;김동진;김병민;김광호
    • 한국정밀공학회지
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    • 제18권9호
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    • pp.110-121
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    • 2001
  • During hot pipe bending using induction heating, the wall of bending outside is thinned by tensile stress. In design requirement, the reduction of wall thickness is not allowed to exceed 12.5%. So in this study, two methods of bending, one is loading of reverse moment and the other is loading of temperature gradient, have been investigated to design pipe bending process that satisfy design requirements. For this purpose, finite element analysis with a bending radius 2Do(outer diameter of pipe) has been performed to calculate proper reverse moment and temperature gradient to be applied. Induction heating process has been analyzed to estimate influence of heating process parameters on heating characteristic by finite difference method. Then pipe bending experiments have been performed for verification of finite element and finite difference analysis results. Experimental results are in good agreement with the results of simulations.

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콤바인 HST 전자제어시스템 개발 (I) (Development of a Combine HST Electronic Control System (I) - Indoor Tests for Control Characteristics -)

  • 서신원;허윤근;이제용;이창규
    • 농업과학연구
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    • 제37권2호
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    • pp.295-302
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    • 2010
  • Electro-hydraulic transmission (HST) and an electronic control system was designed, and performance of the components were investigated through indoor tests. When input values for HST swash plate control were given at 3 levels (5, 10, 13 degrees) in forward and reverse directions, the errors were less than 0.6 degrees. Response time was in ranges of 0.14 ~ 0.16 s and 0.16 ~ 0.2 s for forward and reverse direction controls while driving, and the values were 0.23 ~ 0.25 s and 0.18 ~ 0.23 s at static condition, respectively. Similar experiments for left and right steering resulted errors less than 0.5 degrees. Resonse time was in ranges of 0.16 ~ 0.22 s and 0.11 ~ 0.23 s for left and right turns while driving, and the values were 0.07 ~ 0.21 s and 0.09 ~ 0.14 s at static condition, respectively. From frequency response experiments, control system appeared to follow sine waves appropriately at frequencies less than 0.8 Hz with gain of 0.11 dB and 0.09 dB for forward and reverse direction controls, respectively, and the gain decreased above the frequency. Phase difference showed a gradual increase and were less than 45 degree up to 0.8 Hz. Similar experiments for left and right streering showed that the control system appeared to follow sine waves appropriately at frequencies less than 0.8 Hz with gain of 0.28 dB and 0.26 dB for left and right steering controls, respectively, and the gain decreased above the frequency. Phase difference showed a gradual increase and were less than 45 degree up to 0.8 Hz, which was the same as for the forward and reverse controls.

역공학에서의 노이즈가 포함된 측정데이터의 분할에 관한 연구 (Study on Segmentation of Measured Data with Noise in Reverse Engineeing)

  • 이석희;김호찬;허성민
    • 대한기계학회논문집A
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    • 제26권3호
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    • pp.560-569
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    • 2002
  • The segmentation has been performed to the data of good quality in most cases, so the adoption of previous segmentation theory to the measured data with a laser scanner does not produce good result because of the characteristics of the data with noise component. A new approach to perform the segmentation on the scanned data is introduced to deal with problems during reverse engineering process. A triangular net is generated from measured point data, and the segmentation on it is classified as plane, smooth and rough segment. The segmentation result in each segment depends on the user-defined criteria. And the difference of the segmentation between the data of good quality and the data with noise is described and analyzed with several real models. The segment boundaries selected are used to maintain the characteristics of the parts during modeling process, thus they contribute to the automation of the reverse engineering.

HSS을 적용한 STI CMP 공정에서 EPD 특성 (A study of EPD for Shallow Trench Isolation CMP by HSS Application)

  • 김상용;김용식
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2000년도 춘계학술대회 논문집 전자세라믹스 센서 및 박막재료 반도체재료 일렉트렛트 및 응용기술
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    • pp.35-38
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    • 2000
  • In this study, the rise throughput and the stability in fabrication of device can be obtained by applying of CMP process to STI structure in 0.l8um semiconductor device. Through reverse moat pattern process, reduced moat density at high moat density, STI CMP process with low selectivity could be to fit polish uniformity between low moat density and high moat density. Because this reason, in-situ motor current end point detection method is not fit to the current EPD technology with the reverse moat pattern. But we use HSS without reverse moat pattern on STI CMP and take end point current sensing signal.[1] To analyze sensing signal and test extracted signal, we can to adjust wafer difference within $110{\AA}$.

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