• Title/Summary/Keyword: Contact Area

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Optimization of the Gear Tooth Crowning Amount Considering Contact Subsurface Stress (표면아래응력을 고려한 기어이의 크라우닝 최적화에 관한 연구)

  • Lee, Sang-Don;Kim, Jong-Sung;Cho, Yong-Joo
    • Tribology and Lubricants
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    • v.25 no.1
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    • pp.38-42
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    • 2009
  • Gear is an essential component of an automotive. Crowning is used for tooth modification of a gear. The basic concept of gear tooth crowning is to reduce the stress concentration in edge of contact area and appropriate profile modifications can help gears to resist scoring, pitting, and tooth breakage. In this study, a method to determinate spur gear tooth crowning amount to make smooth surface stress and subsurface stress distribution is proposed. This method is based on the contact analysis.

Guided-Wave Tomographic Imaging of Plate Defects by Laser-Based Ultrasonic Techniques

  • Park, Junpil;Lim, Juyoung;Cho, Younho
    • Journal of the Korean Society for Nondestructive Testing
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    • v.34 no.6
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    • pp.435-440
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    • 2014
  • Contact-guided-wave tests are impractical for investigating specimens with limited accessibility and rough surfaces or complex geometric features. A non-contact setup with a laser-ultrasonic transmitter and receiver is quite attractive for guided-wave inspection. In the present work, we developed a non-contact guided-wave tomography technique using the laser-ultrasonic technique in a plate. A method for Lamb-wave generation and detection in an aluminum plate with a pulsed laser-ultrasonic transmitter and Michelson-interferometer receiver was developed. The defect shape and area in the images obtained using laser scanning, showed good agreement with the actual defect. The proposed approach can be used as a non-contact online inspection and monitoring technique.

A Study on the Process Encounter for Service Quality Control : Focusing on franchise restaurant (서비스품질 관리를 위한 프로세스 접점에 관한 연구 : 프랜차이즈 외식업을 중심으로)

  • Kim, Sang-Cheol
    • Journal of Distribution Science
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    • v.11 no.8
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    • pp.25-30
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    • 2013
  • Purpose - Foodservices have grown to over 60% of the franchise industry. However, despite reaching this high level, the foodservice franchise industry is experiencing severe ups and downs. While factors such as expansion by franchises and the entry of large multinational firms are causing this imbalance, the more serious problem faced by franchisees is the lack of know-how and correct operating procedures. Franchise headquarters should advise franchisees on important matters such as food ingredients, interior design, tableware, and fixtures. However, even though franchise headquarters have the ability to impart such management know-how, this is often a neglected area. Research design, data and methodology - This study was conducted in an industrial environment to present suitable competitive alternatives for foodservice franchises. Empirical analysis was conducted using a sample of 232 people with experience in targeting customers. The main purpose of this study is not to identify and analyze the factors affecting customer satisfaction. Customers of the Food Service Industry to invite contacts until departure for the service flow by identifying the expectations and allow this area by analyzing the resulting measures to enhance the competitiveness has presented. Results - Actual results contact factors affecting the quality of service on customer satisfaction was a significant influence. However, the end of this analysis, the actual customer satisfaction directly affects the quality of service that is only important factor can commit mistakes. Relatively large impact on customer satisfaction, which is relatively independent of the quality factor should be a review of zone of tolerance. In this study, eating phase relative to contact the service customer satisfaction was the most influential. The results, however, zone of tolerance for an area in the waiting and ordering dissatisfaction factors are appearing. And in the course of these services outside the zone of tolerance area is unsatisfactory evaluation is being done. Conclusions - After all, Foodservice, the contact service management for zone of tolerance the top priority should be can be seen. Foodservice contact first in the case of service quality factors caused by the continuous flow of services, so this step-by-step identification needs to be clearer. This, of course, to distinguish between the actual per unit of activity appears to be more difficult to follow, for it seems to need a lot of future complementary. Next is the assessment of customer service quality. Customers remember the experience for the services of a real contact through the assessment and service evaluation clearly emerge as the expected level can be difficult. However, this situation is controlled by the test method cannot be avoided unless there is no limit to the number of leave. Despite these limitations, the next step to contact a service evaluation and analysis have to continue to refine and thereby franchisees for the operation of the store in terms of practical know-how required to provide to the office believe.

Effects of Interactive Metronome Training on the Plantar Pressure and Fall Efficacy in Chronic Stroke Patients (상호교환식 메트로놈 훈련이 만성 뇌졸중 환자의 족저압과 낙상효능감에 미치는 영향)

  • Hwang, Won Kyung;Lee, Han Suk;Park, Sun Wook
    • Journal of the Korean Society of Physical Medicine
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    • v.15 no.1
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    • pp.105-112
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    • 2020
  • PURPOSE: This study examined the effects of Interactive Metronome training on the plantar pressure and fall efficacy in chronic stroke patients. METHODS: Twenty-two hemiplegic patients were allocated randomly to an experimental group and control group. The experimental group received conventional physical therapy and emphasized weight-bearing interactive metronome training, whereas the control group received conventional physical therapy. The training was performed three times per week, 40 minutes per each session, for a total of seven weeks. The plantar pressure was assessed using the contact area and contact pressure, whereas the fall efficacy was assessed using the FES (Fall Efficacy Scale), ABC (Activities-specific Balance Confidence scale) and FOFQ (Fear of Falling Questionnaire). RESULTS: After training, a significant increase was observed in the paretic side of the contact area and the paretic and non-paretic side of contact pressure in both groups (p<.05). The between-group differences in the changes before and after training were statistically significant in the paretic side of the contact pressure (p<.05). After training, both the FES of the between-group and ABC of the experimental group were increased significantly (p<.05), but the between-group differences in the changes before and after training were not statistically significant in the FES, ABC, and FOFQ (p>.05). CONCLUSION: Interactive Metronome training is considered an effective treatment for improving the contact pressure of the paretic side in chronic stroke patients.

A Study on the contact to lascivious computer programs and sexual attitude and behaviour by the grade of middle school students in Pusan and Kimhae area (부산 . 경남지역 중학교 남학생의 학년에 따른 컴퓨터 음란물 접촉실태에 관한 연구)

  • 손혜숙;김혜옥;김대환;이종태
    • Korean Journal of Health Education and Promotion
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    • v.16 no.2
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    • pp.55-66
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    • 1999
  • To evaluate the status of the contact to lascivious computer programs and sexual attitude and behaviour by the grades of middle school boy students, the questionnaire survey was done on 715 students of five middle schools in Pusan and Kimhae area from December 15 to December 24, 1997. The data were analyzed by PC SAS; $X^2$ -test. The level of significance was 0.05. 404 students (56.5%) had a personal computer in their home. 516 students(72.2%) have experienced of using a computer program. 294(57%) of them usually played a game with computer. 514 students(71.9%) had experiences of the contact to a lascivious computer program, which increased with the grades of the students(p〈0.05). The first exposure to a lascivious program was when they were elementary school students in 24.6% of first grade middle school student, 13.8% of second grade, and 11.3% of 3rd grade students. 92% of the students was introduced to first contact through their friends. 63.7% of them watch the program at their friends home. The most common drives to contact to a lascivious programs were curiosity (53%). Sexual desire was a higher drive in third grade students (20.6%) than lower grades. After contacting to a computer lascivious program, desire of masterbation was more frequent in lower grade students. and feeling disgust was more frequent in higher grade students (p〈0.05). Frequence of masterbation or sexual intercourse was higher in high grade students(p〈0.05) In conclusion, distribution and popular use of computer attributes to the increased exposure to lascivious programs and lowering the age of first exposure. There was the difference according to the grades in the feeling and sexual behaviour after contacting to computer lascivious program. Appropriate methods to protect young students to contact a lascivious program should be sought. The use of computer should be educated in elementary school students accompanied by proper sex education.

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High Quality Nickel Atomic Layer Deposition for Nanoscale Contact Applications

  • Kim, Woo-Hee;Lee, Han-Bo-Ram;Heo, Kwang;Hong, Seung-Hun;Kim, Hyung-Jun
    • Proceedings of the Materials Research Society of Korea Conference
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    • 2009.05a
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    • pp.22.2-22.2
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    • 2009
  • Currently, metal silicides become increasingly more essential part as a contact material in complimentary metal-oxide-semiconductor (CMOS). Among various silicides, NiSi has several advantages such as low resistivity against narrow line width and low Si consumption. Generally, metal silicides are formed through physical vapor deposition (PVD) of metal film, followed by annealing. Nanoscale devices require formation of contact in the inside of deep contact holes, especially for memory device. However, PVD may suffer from poor conformality in deep contact holes. Therefore, Atomic layer deposition (ALD) can be a promising method since it can produce thin films with excellent conformality and atomic scale thickness controllability through the self-saturated surface reaction. In this study, Ni thin films were deposited by thermal ALD using bis(dimethylamino-2-methyl-2-butoxo)nickel [Ni(dmamb)2] as a precursor and NH3 gas as a reactant. The Ni ALD produced pure metallic Ni films with low resistivity of 25 $\mu{\Omega}cm$. In addition, it showed the excellent conformality in nanoscale contact holes as well as on Si nanowires. Meanwhile, the Ni ALD was applied to area-selective ALD using octadecyltrichlorosilane (OTS) self-assembled monolayer as a blocking layer. Due to the differences of the nucleation on OTS modified surfaces toward ALD reaction, ALD Ni films were selectively deposited on un-coated OTS region, producing 3 ${\mu}m$-width Ni line patterns without expensive patterning process.

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Occurrence and Physico-chemical Properties of the Smectite-rich Clays from the Samcheok Area in Kangwon-do, Korea (강원도 삼척지역의 스멕타이트질 점토의 산상 및 특성)

  • Hwang, Jin-Yeon;Park, Seong-Wan;Lee, Sang-Hyon;Choi, Soo-Yong
    • Economic and Environmental Geology
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    • v.28 no.1
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    • pp.1-8
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    • 1995
  • The smectite-rich clays were found locally in Paleozoic calcareous sedimentary rocks in the Samcheok area. Their occurrences were investigated in detail, and the physico-chemical properties of the clays were also determined by X-ray diffraction, chemical analysis, thermal analysis and cation exchanging experiment. The smectite clays occur as the fissure filling dyke developed in calcareous sedimentary rock and as alteration products of intrusive rhyolite. Most of clays occur at the contact between the sedimentary rock and the rhyolite, and the alteration zone was observed only in rhyolite body close to the contact. Judging from their occurrences, it is believed that the smectite-rich clays in this area were formed by the hydrothemal alteration. The smectite clays from the area are mainly composed of Ca-montmorillonite, and associated with small quantities of quartz, opal-CT and feldspar. The montmorillonites from this area are lower in Fe content, and higher in exchangeable Ca ion, compared to those of bentonite from the Yangnam-Yeongil area.

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A Study on Stable Grasping Control of Dual-fingers with Soft-Tips (소프트-팁이 장착된 듀얼-핑거의 안정적 파지 제어에 관한 연구)

  • 심재군;한형용;양순용;이병룡;안경관;김성수
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 2002.10a
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    • pp.219-224
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    • 2002
  • This paper aims to derive a mathematical model of the dynamics of handling tasks in robot finger which stable grasping and manipulates a rigid object with some dexterity. Firstly, a set of differential equation describing dynamics of the manipulators and object together with geometric constraint of tight area-contacts is formulated by Lagrange's equation. Secondly, problems of controlling both the internal force and the rotation angle of the grasped object under the constraints of area-contacts of tight area-contacts are discussed. The effect of geometric constraints of area-contacts on motion of the overall system is analyzed and a method of computer simulation for overall system of differential-algebraic equations is presented. Thirdly, simulation results are shown and the effects of geometric constraints of area-contact is discussed. Finally, it is shown that even in the simplest case of dual single D.O.F manipulators there exists a sensory feedback from sensing data of the rotational angle of the object to command inputs to joint actuators and this feedback connection from sensing to action eventually realizes secure grasping of the object, provided that the object is of rectangular shape and motion is confined to a horizontal plane.

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A STUDY OF THE NORMAL & ABNORMAL OCCULSAL PATERNS IN ADULTS USING THE SUPERIMPOSED RUBBER PATTERN METHOD (Superimposed Rubber Pattern법에 의한 성인 정상 및 비정상 교합자의 교합 양상에 관한 연구)

  • Choi, Dae-Gyun;Lee, Sung-Bok;Kwon, Young-Hyuk;Choi, Boo-Byung
    • The Journal of Korean Academy of Prosthodontics
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    • v.33 no.3
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    • pp.467-491
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    • 1995
  • In order to analyze the occlusin of intercuspation with maximun bite force, fifteen healthy adult subjects with the ages 23 to 27 were studied(Group1 ; 5-normal occlusion with Angle's Class1, Group2 ; 5-Angle's Class2 malocclusion, Group3 ; 5-Angle’s Class3 malocclusion). Head Position was fixed with occlusal plane paralleling to horizontal line and occlusal registration r cord was made with polyether rubber impression material(Ramitec, ESPECo. West Germany). After all subject were trained for maximum intercuspation at least 5 times, occlusal registration procedure was repeated for this study. Lower posterior rubber occlusal registration records were sliced with 1mm thickness using precision metal sliding channel(Hitachi Ind. Co., Japan). Gross sectional drawings were traced from occluding view of upper and lower posterior teeth on the rubber slices using digitizer, and superimposed for the determination of each drawing distance(Superimposed Rubber Pattern Method). Based on superimposed rubber pattern drawings, total area of occlusal view, sum of each area of the 5 divided occlusal contact provinces and its ratio, total area and number of occlusal contact area were determined to elucidate occlusal stability in the normal and abnormal occlusion groups. The data were analysed by t-test(p=0.05) to determine statistical significance. The obtained results were as follows : 1. Group1 showed the largest standard area with occlusal view of the lower posterior teeth and Group3 showed the smallest area. There was a significant difference between Group2 and Group3(p=0.025), and Gropu1 was not statistically different for both Group2 and Group3. 2. Means and ratio of the under 2.0mm area(D) and ratio showed $197.49mm^2$, 59.76% in Group1, $188,69mm^2$, 56.10% in Group2, and $174.23mm^2$, 55.76% in Group3. The results that Group1 has the most area/ratio and Group3 has the least area/ratio can be considered Group1 is the most advantageous for masticatory effective area, and Group3 is the least adnantageous. 3. Means and ratio of the under 1.0mm area(C) were $198.96mm^2$, 42.65% in Group1, 123.06$mm^2$, 46.58% in Group2, and $92.24mm^2$, 29.52% in Group3. These data means that Group1 is the most advantageous in terms of masticatory effective area and Group3 is the least. 4. Means and ratio of the under 0.5mm area(B) were $86.68mm^2$, 26.68% in Group1, $62.98mm^2$, 18.71% in Group2, and $36.44mm^2$, 11.66% in Group3. These can also be considered Group1 is the most advantageous for masticatory effective area and occlusal stability. 5. Means and ratio of the under 0.05mm area(A) were $30.92mm^2$, 9.21% in Group1, $14.31mm^2$, 4.25% in Group2, and $7.59mm^2$, 2.43% in Group3. The area ratio of the each subject group was(4.1) : (1.9) : (1)and the data of the under 0.05mm area has the intimate relationship with inter-group and intra-group data/ratio. 6. First molar showed the most occlusal contact points in all subject group and Group1 showed somewhat uniformly distributed occlusal contact point except first premolar. In Group2, all contact point in posterior teeth showed significantly reduced distribution except first molar. Group3 showed evenly distributed contace points in first and second molars.

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Comparisons of Foot Pressure Patterns between Experienced Skiers and Intermediate Skiers during Alpine Skiing (알파인 스킹 시 상급 스키어와 중급 스키어 간의 족저압력 패턴 비교)

  • Kim, Joo-Nyeon;Yoo, Si-Hyun;Ha, Sung-He;Kim, Jin-Hae;Ryu, Ji-Seon;Park, Sang-Kyoon;Yoon, Suk-Hoon
    • Korean Journal of Applied Biomechanics
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    • v.24 no.1
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    • pp.19-26
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    • 2014
  • This study investigated foot pressure patterns between experienced skiers and intermediate skiers during alpine skiing. Five experienced skiers and five intermediate skiers participated in this study. Foot pressure measurement system was used to measure vertical ground reaction force (vGRF) and contact area under the six plantar regions. Each participant was asked to perform basic parallel turns and carved turns on a $18^{\circ}$ groomed slope. Each right turn was divided into the initiation phase, the steering phase 1 and 2. For the initiation phase of the basic parallel turns, significantly greater contact area was found on the LRF and RRF of the intermediate skiers (p<.05) and significantly greater vGRF was found on the LRF of the intermediate skiers (p<.05). Also significantly greater vGRF and contact area were found on the LRF and RRF of the intermediate skiers at the steering phase 1 (p<.05) and on the LRF of the intermediate skiers at the steering phase 2 (p<.05). For the carved turns, significantly greater vGRF and contact area were found on the LRF and RRF of the intermediate skiers at all three phase (p<.05). On the other hand, significantly greater vGRF was found on the RFF of the experienced skiers at the steering phase 1 (p<.05). Also significantly greater vGRF and contact area were found on the RMF of the experienced skiers at the steering phase 2 (p<.05). In order to increase performance, we suggest that the intermediate skiers should be unweighted at the initiation phase and shift the body weight to the forefoot of the outer foot at the steering phase 1. Also, the outer ski should be loaded more than the both skis at the steering phase 1 and 2.