• Title/Summary/Keyword: backward difference

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Research on the Amount To Be Removed at the Neckline According to the Upper Chest Type (흉부상부형태에 따른 네크라인의 줄임분량에 관한 연구)

  • Koo, Mi-Ji
    • Korean Journal of Human Ecology
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    • v.10 no.4
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    • pp.391-398
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    • 2001
  • This research is focused on how to divide the upper chest type and to find out the amount to be removed at the neckline according to the different upper chest type and different neckline depth. The result of the research is as followed. 1. In the result of the factor analysis, the upper chest could be explained by six factors such as the shape factor of the upper chest, shoulder curve factor, shoulder sloping factor, space factor from shoulder to waist, upper chest slope factor, and the bust size factor. 2. The shape of the upper chest could be divided by three groups. The first group is characterized as lagging and bent backward shoulder, slight slope of upper chest, and small bust. The second group is comparatively curved at the upper chest and big bust. The third group is rising and bent forward shoulder, slight curved upper chest. 3. The amount to be removed at the different neckline depth and in these three types of upper chest had a difference due to the differences of the upper chest shape containing the shoulder shape.

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Effect of Inclination Angle on the Heat Transfer and Pressure Drop Characteristics of Parallel Flow Heat Exchanger (경사각이 PF 열교환기의 열전달 및 압력 손실에 미치는 영향)

  • Kim, Do-Young;Ham, Jung-Ho;Kim, Nae-Hyun;Park, Nae-Hyun;Hwang, Jun-Hyun
    • Proceedings of the SAREK Conference
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    • 2007.11a
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    • pp.222-228
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    • 2007
  • The effect of inclination angle on the heat transfer and pressure drop characteristics of brazed aluminum heat exchangers is experimentally investigated. Three samples having different fin pitches (1.25, 1.5 and 2.0 mm) were tested. Results show that heat transfer coefficient is not affected by the inclination angle. However, the friction factor increases as the inclination angle increases with negligible difference between the forward and backward inclination. Both the heat transfer coefficient and the friction factor are the smallest at $P_f$=1.5mm, followed by $P_f$=2.0mm and 1.25mm. Possible explanation is provided considering the louver layout. Comparison with existing correlations is also mad.

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Turn-on/off Angle for Maximum Torque of SRM by Using Self-tuning Control (SRM의 자기동조 방식에 의한 최대토크의 턴-온/오프각 제어)

  • Seo Jong-Yun;Cha Hyun-Rok;Seo Jung-Chul;Yang Hyong-Yeol;Kim Kwang-Heon;Lim Young-Cheol;Jang Do-Hyun
    • Proceedings of the KIPE Conference
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    • 2001.07a
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    • pp.243-246
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    • 2001
  • The control of the SRM(Switched Reluctance Motor) is usually based on the non-linear inductance profiles with positions. So determination of optimal switching angle is very different. This paper proposed that the determination method of turn-on/off angle in the SRM drives is to maintain the high torque, which is realized by using self-tuning control method. During the sampling time, a number of pulses from the encoder are checked by using micro-controller. And compared with pre-checked a number of pulses. After calculating difference between two data, turn-on/off angle moves forward or backward direction by using self-tuning method. The optimal turn-on/off angle is determined by iterating such a process and the maximum torque is maintained. Experimental results are provided to demonstrate the validity of the self-tuning controller.

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An Internet Time Synchronization Model using Dynamic Linear Model (동적선형모델을 적용한 인터넷 시각동기 모델)

  • Yu, Dong-Hui;Hwang, So-Young;Kim, Yong-Ho
    • The KIPS Transactions:PartC
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    • v.10C no.6
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    • pp.711-716
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    • 2003
  • We propose a new Interet time synchronization model using danamic linear model and introduce the characteristics of internet transmission delays. SNTP(Simple Network Time Protocol) has been widely used as a time synchronization method on the Internet. While SNTP provides a very simple usage, SNTP may not provide the stable services, since SNTP does not consider the several essential error factors. In order to overcome the instabitily of SNTP, we analyze the process of time estimation of SNTP and find the difference between forward transmission delay and backward transmission delay operates the main error on the estimation of an time offset.

A Study on Parking Guideline Generation Algorithm (주차 가이드라인 생성 알고리즘에 대한 연구)

  • Heo, Jun-Ho;Lee, Seon-Bong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.5
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    • pp.3060-3070
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    • 2015
  • Recently, novice driver or weak drivers was difficult to understand the movement characteristics of the car and are immature sense of width and length of the car according to various each driver's sex and age, model. To complement this problem, the use of rear sensor and the camera is increased. And the parking assistance system that improves the convenience of parking the driver is being developed. Accordingly, parking guide system is needed to reflect the difference in the steering angle and correct the error distance. In this study, it is proposed that the turning radius during backward by complementing the existing Ackerman Jentaud type. And it develops more accurate parking guideline to be able to generat algorithm by applying the formula to propose a steering wheel angle sensor value derived through the handle.

Effect of Paretic and Non-paretic Side Spine Taping on Balance Ability in Patients with Stroke

  • Cho, Yonghun;Park, Shinjun;Kim, Soonhee
    • Journal of International Academy of Physical Therapy Research
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    • v.10 no.2
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    • pp.1779-1784
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    • 2019
  • Background: A number of researchers have attempted to improve the balance of stroke patients, however there is still a question as to whether taping is effective in increasing balance. Objective: To determine the effect of paretic and non-paretic side taping on the balance ability in patients with stroke. Design: A single-blind randomized controlled trial Methods: This randomized single-blind controlled clinical trial with a repeated measures study included 45 subjects who were randomly assigned to paretic side taping groups (n=15), non-paretic side taping groups (n=15), and trunk exercise groups (n=15). Trunk exercise and paretic side taping groups had taping on the paralyzed erector spinae, while the non-paretic side taping group had taping on the non-paralyzed erector spinae. Trunk exercises were performed for 30 minutes to promote core muscles. The balance ability measured the center of pressure movement (paretic side, non-paretic side,forward, backward, limit of stability) in the sitting position. All measurements were evaluated using BioRescue. Results: All three groups showed significant increase in all variables after 4 weeks. The paretic and non-paretic side taping groups had a significant increase in all variables after 30 min of attachment. However, there was no significant difference among the three groups. Conclusions: Paralysis and non-paralysis taping improved the balance ability of patients with stroke in an immediate effect of 30 min. However, after 4 weeks of intervention, taping with trunk exercise did not differ from single trunk exercise. In future studies, various analyses need to be conducted through more diverse evaluations.

Study on Design and Driving Characteristics of T-Shaped Piezoelectric Actuators (T형상 압전 엑추에이터의 설계 및 구동특성 연구)

  • Kim, Tae-Hoon;Park, Min-Ho;Jeong, Seong-Su;Jun, Ho-Ik;Cheon, Seong-Kyu;Park, Tae-Gone
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.32 no.1
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    • pp.30-34
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    • 2019
  • A newly proposed T-shape piezoelectric actuator, composed of piezoelectric benders, was designed and studied. This actuator has four legs, and can walk in both forward and backward directions. The piezoelectric actuator has a simple structure and can be easily fabricated. It consists of a piezoelectric bender and a joint. The piezoelectric bender is composed of carbon and ceramic materials. Therefore, there is an advantage in that it can be fabricated on a very small scale. Elliptical displacements of the piezoelectric actuators were analyzed by finite element analysis. Elliptical motion at the tip occurred at two voltages having a 90-degree phase difference. Based on the finite element analysis results, prototype actuators with maximum displacements were fabricated, and the characteristics of their movements were characterized.

Channel Electrode Voltammetric and In Situ Electrochemical ESR Studies of Comproportionation of Methyl Viologen in Acetonitrile

  • Lee, Ji U;John C. Eklund;Robert A. W. Dryfe;Richard G. Compton
    • Bulletin of the Korean Chemical Society
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    • v.17 no.2
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    • pp.162-167
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    • 1996
  • Two redox processes of methyl viologen (+2/+, +/0) in acetonitrile were investigated by using channel electrode voltammetric and in situ electrochemical ESR methods. Two separated unequal plateau currents of the first (+2/+) and second (+/0) redox processes of the viologen were observed in the channel electrode voltammograms and showed a cube-root depedndence on the electrolyte flow rate, respectively. The simple Levich analysis resulted in two different diffusion coefficients of $D_{+2}=2.2{\times}10^{-5}\;cm^2/s$ and $D_+=3.0{\times}10^{-5}cm^2/s$ from the limiting currents. In situ electrochemical ESR studies were performed for the monocation radicals generated at the potentials of the two plateau currents in the electrolyte flow range $1.3{\times}10^{-1}{\geq}v_f{\geq}2.7{\times}10^{-3}\;cm^3/s$. Backward implicitfinite difference method was employed to simulate the electrochemical kinetic problem of two sequential electron transfers ($MV^{+2}+e{\leftrightarrows}MV^+,\;MV^{+}+e{\leftrightarrows}MV^0$) coupled with reversible comproportionation ($MV^{2+}+MV^0{{\leftrightarrows}^{k_f}_{k_b}}2MV^+$). $k_f$ was found to be greater than ($10^6M^{-1}s^{-1}.

Setback genioplasty with rotation for aesthetic mentolabial soft tissue: a case report

  • Joon-Bum Hong;Joo-young Ohe;Gyu-Jo Shim;Yong-Dae Kwon
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.49 no.6
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    • pp.365-368
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    • 2023
  • The mentum plays an important role in the aesthetics of the face, and genioplasty is performed to improve an unbalance of the mentum. Among the various surgical approaches, setback genioplasty is used to create an aesthetic jaw-end appearance by moving the mentum backward when it protrudes more than normal. However, conventional setback genioplasty may be aesthetically disadvantageous because the profile of the mentum could become flat. This case study attempted to overcome the limitations of conventional setback genioplasty by rotating the position of the menton and pogonion. We devised a new method for setback genioplasty by rotating the segment anteroinferiorly. Using virtual surgery, we were able to specify the range of surgery more accurately and easily, and the surgery time was reduced. This case report showed the difference in chin soft tissue responses between conventional setback genioplasty and setback genioplasty with rotation.

A Study on Development of WBI Program and Application for Learning Probability and Statistics in the Middle School (웹 기반의 중학교 확률과 통계를 중심으로 한 WBI 프로그램 개발 및 적용에 관한 연구)

  • 강청귀
    • Journal of the Korean School Mathematics Society
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    • v.4 no.2
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    • pp.49-60
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    • 2001
  • This paper is dedicated to the enhancement of the second-grade students of middle school students' understanding of the basic principles and concepts of probability with the help of Web-browser-used WBI programs relating to probability and statistics in teaching them the unit of probability. I have come up with the following research problems with a view to applying and analyzing the findings. (1) A web sites in relation to the learning of probability and statistics is to be developed with the second graders of middle school in mind. (2) Is there any difference between the experiment group exposed to web-sites-aided classes and the control group going through the conventional ways of math classes when the sites is made trial use of \ulcorner (3) What response do the learners show in regard to classes which makes use of the web sites when the sites is applied\ulcorner After making an experiment with the aid of the web sites and teaching plans, I made a measurement and an analysis of the academic achievement of the subjects, their understanding of classes based on the web sites, the concentration of the learners, and their responses relating to the contents of web sites concentrating on probability and statistics. I have come to the following conclusions based on the findings. First there was a significant difference between the classes of honor students and the classes of backward pupils when T-Test was made with regard to the achievement of the subjects who divided into the experiment group and the control group. The former made use of the web sites whereas the latter stuck to the conventional way of teaching math. The former scored higher than the latter. Second, the research based on questionnaire findings shows that the web-site-aided experiment classes proved to be more effective than the traditional control classes. All in all, I think that web-aided classes will have a more positive influence on the students' interest in math and on the scholastic achievement of math than conventional classes.

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