• Title/Summary/Keyword: Hold-back

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Robust Rear Center-Hinge Bracket Optimization Based on Taguchi Method (다구찌 방법을 활용한 Rear Center-Hinge Bracket 강건 설계)

  • Jung, Sebin;Kim, Minho
    • Transactions of the Korean Society of Automotive Engineers
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    • v.22 no.3
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    • pp.203-209
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    • 2014
  • The rear center-hinge bracket is designed for supporting and folding the rear-seat backrest. This bracket needs to be strong enough to be able to rigidly hold the rear-seat backrest and to withstand luggage loads from the car trunk that are generated when a vehicle is driving on the roads. Particularly, current accident studies report that many serious occupant injuries occurred when the rear-seat back easily folded inward toward the car interior, driven by the luggage loads in the trunk. Given this fact, the robust design of the rear center-hinge bracket that mainly supports the rear backrest has become more important for providing customer safety and preventing high warranty and durability problems. However, none of the studies have emphasized its significant role and considered its robust optimization. Therefore, this paper presents how the hinge-bracket design is optimized based on an application of the finite-element method coupled with the parameter design using Taguchi's design experiment. Finally, Taguchi method's application optimizes a robust center-hinge bracket that shows more rigid performance although it has lighter weight and thinner thickness.

Characteristics of Motion-blur Free TFT-LCD using Short Persistent CCFL in Blinking Backlight Driving

  • Han, Jeong-Min;Ok, Chul-Ho;Hwang, Jeoung-Yeon;Seo, Dae-Shik
    • Transactions on Electrical and Electronic Materials
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    • v.8 no.4
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    • pp.166-169
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    • 2007
  • In applying LCD to TV application, one of the most significant factors to be improved is image sticking on the moving picture. LCD is different from CRT in the sense that it's continuous passive device, which holds images in entire frame period, while impulse type device generate image in very short time. To reduce image sticking problem related to hold type display mode, we made an experiment to drive TN-LCD like CRT. We made articulate images by turn on-off backlight, and we realized the ratio of Back Light on-off time by counting between on time and off time for video signal input during 1 frame (16.7 ms). Conventional CCFL (cold cathode fluorescent lamp) cannot follow fast on-off speed, so we evaluated new fluorescent substances of light source to improve residual light characteristic of CCFL. We realized articulate image generation similar to CRT by CCFL blinking drive and TN-LCD overdriving. As a result, reduced image sticking phenomenon was validated by naked eye and response time measurement.

A Status Analysis on the Field Management of Professional Construction Firms after Abrogation of Construction Participants System (시공참여자제도 폐지 이후 전문건설업체의 현장관리 실태분석)

  • Park, Kyoung-Hun;Kim, Hwa-Joong;Son, Chang-Baek
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2009.11a
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    • pp.199-203
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    • 2009
  • After the construction participants system is abolished, expectations are high for its consequences such as liquidating paper-companies, holding back low price contracts, and improving multi-stepwise subcontract structure. However, the professional construction firms have been took responsibilities and obligations as businessmen employing the chief workmen and construction workers. For this reason, it is expected that they will be charged a great deal of expenses such as increase in labor management services and laborers, the occurrence of an retirement grants, insurance fees, etc. Since the hold on power of field managers are getting weaker toward the construction workers, it is most likely to have loss in efficiency of production in the long term. Therefore purpose of this research is to analyze difficulties and the point at issues with which professional construction firms are undergoing after abolishing the construction participants system by investigating on the actual condition in the field management. For this research, we got a grip on the actual condition and analyzed the rise of a primary factor on reinforced concrete construction.

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Experimental Study on the Opening Characteristics for Swing Check Valves (스윙형 역지 밸브의 열림 특성에 관한 실험적 연구)

  • Song, Seok-Yoon;Kim, Yang-Seok;Park, Sung-Keun;Hong, Sung-Yull
    • 유체기계공업학회:학술대회논문집
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    • 2003.12a
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    • pp.555-561
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    • 2003
  • The experimental apparatus is designed and installed to measure the disc positions with flow velocity, $V_{open}\;and\;V_{min}$ for 3 inch and 6 inch swing check valves. The minimum flow velocity necessary to just open the disc at a full open position is referred to as $V_{open}\;and\;V_{min}$ is defined as the minimum velocity to fully open the disc and hold it without motion. In the experiments, $V_{min}$ is determined as the minimum flow velocity at which the back stop load begins to increase after the disc is idly opened or the oscillation level of disc is reduced below $1^{\circ}$. The results show that the $V_{min}$ velocities for 3 inch and 6 inch swing check valves are about 15.6% and 4.8% higher than the $V_{open}$ velocities, respectively. Although the experiments were done with the stable uniform flow, additional experiments will be performed to determine the effects of the upstream disturbances.

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Development of Squirrel-Cage Induction Motor for 5-Phase 1.5kW (5상 1.5kW 농형 유도전동기 개발)

  • Kim, Min-Huei;Jung, Hyung-Woo;Song, Hyun-Jik
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.28 no.1
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    • pp.57-68
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    • 2014
  • This paper propose a development of squirrel-cage induction motor(IM) for 5-phase 1.5kW, 220V, 60Hz in order to study a polyphase ac machinery that keep hold of advantages more than traditional three-phase a IM, such as reducing a amplitude of torque pulsation, decreasing electric noises, and increasing the reliability. Designed methods of the motor use a development tools with Maxwell 2D and Simplorer program. There are designed drawing of manufactured frames of the IM. amplitude and waveform of the generated electromotive force, FFT analysis of harmonics within output voltages and current, and reviewing a experiment results are shown by variable output. We are presenting a design and manufacture methods for the 5-phase squirrel-cage IM.

Analytic Comparisons of Shipbuilding Competitiveness between China and Korea

  • Lee, Koung-Rae
    • Journal of Korea Trade
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    • v.23 no.4
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    • pp.1-16
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    • 2019
  • Purpose - This research empirically proves that global shipbuilding industry leadership has moved to China from Korea. Design/Methodology - Competitiveness is measured by AHP for the weights of comprehensive competitiveness, which is the output mixture of three attributive factors: shipbuilding technology, shipbuilding contract price, and export credit. Findings - China is far ahead of Korea for standard vessels such as bulkers and containerships with competitiveness weights of 0.762 and 0.612, respectively, against 0.238 and 0.388 of Korea. Korea is maintaining its competitiveness only in LNG carriers (174k CBM) with a competitiveness weight 0.621. China and Korea have similar competitiveness for chemical carriers, complex vessels with a small hull size. The sources of Chinese competitiveness are shipbuilding contract price and export credit. With the majority share of standard vessel types in the world fleet, China will hold a bigger market share than Korea in the global shipbuilding industry in the forthcoming years. Implications - The swing factors of market power are shipbuilding technology and contract price. If China fails to further develop shipbuilding technology for shipowners worried about the reliability of the Chinese-built vessels, shipowners may swing back to Korea. The rising Chinese labor cost will expedite this swing in the forthcoming competition. Originality/value - To the best of the author's knowledge, this is the first paper that quantitatively examines the competitiveness of shipbuilding between China and Korea by comparing attributive factors for competitiveness.

Realization of an IEEE 802.11g VoWLAN Terminal with Support of Adaptable Power Save and QoS During a Call (통화 중 적응적 Power Save와 QoS 지원이 가능한 IEEE B02.11g VoWLAN 단말기 구현)

  • Kwon, Sung-Su;Lee, Jong-Chul
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.31 no.10A
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    • pp.1003-1013
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    • 2006
  • There is a serious problem in an 802.11g VoWLAN (Voice over Wireless LAN) terminal that talk time is less than 30% compared with an 802.11b terminal. It is almost impossible to achieve talk time level of the 802.11b MAC transmission method because IEEE 802.11g uses OFDM modulation, which is a kind of multi-carrier method and OFDM transmission speed is 54 Mbps faster than normal modulation. In this paper, a new concept of a Holdover time as a power saving method during a call with 802.11g terminal is suggested for the first time. Increase in the number of engaged terminals as a result of holdover time causes to QoS problem because of the increase in the number of back-off and then contention window. In this paper, to solve the QoS problem, a new approach is suggested such that when in down lint the sequence number of 802.11 G.711 is analyzed in the MAC of the terminal and then the Hold over time depending on loss rate is changed. Also, consumption of an electric current of 802.11b/g and MAC parameter's performance due to busy traffic caused by increase in the number of terminal are analyzed and then real data using VQT and Airopeek are analyzed.

Relationship between Breathing Pattern Disorder and Joint Position Sense in Patients with Chronic Low Back Pain (만성요통환자의 호흡패턴이상과 관절위치감각의 관계)

  • Cho, Byungyun;Yoon, Junggyu
    • Journal of The Korean Society of Integrative Medicine
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    • v.7 no.2
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    • pp.1-10
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    • 2019
  • Purpose : To investigate the relationship between breathing pattern disorder and joint position error (JPE) in patients with chronic low back pain (CLBP). Methods : Thirty nine patients with CLBP participated. End-tidal $CO_2$ and respiration rate (RR) were measured using a capnography. Breathing-hold time (BHT) and Nijmegen Questionnaire (NQ) were investigated. Thoracic excursion was measured with a cloth tape measurement technique. Joint position error were measured using a small laser point mounted on a lightweight headband. they were asked to relocate the head, after the neck movement on the horizontal plane. Pearson 's test was used for correlation analysis between respiratory variables and JPE in patients with CLBP. Independent t-test was used to verify the difference between thoracic and diaphragm breathing pattern in patients with CLBP. The significance level was set at 0.05. Results : There was a significant correlation between JPE (LR) and JPE (RR, EX) (r=.639, r=.813) (p<.001) and a low negative correlation with end-tidal $CO_2$ (r=-.357) (p<.05). There was a significant correlation between RR and JPE (EX) (r=.750) (p<.001). There was a low correlation between JPE (EX) and NQ (r=.333) (p<.05). There was a somewhat high negative correlation between NQ and thoracic excursion (r=-.528) (p<.001). There was a somewhat high negative correlation between thoracic excursion and JPE (LR, RR, EX) (r=-.470, r=-.484, r=-.602) (p<.001). There were no significant differences in the RR, BHT, NQ, and thoracic excursion between the thoracic and diaphragmatic breathing (p>.05). There was a significant difference in the JPE (EX), end - tidal $CO_2$, and VAS values between the thoracic and diaphragm breathing (p<.05). Conclusion : There was a correlation between JPE (EX) and NQ in patients with CLBP, and correlation between thoracic excursion and JPE (LR, RR, EX) and NQ. There was a significant difference in the JPE (EX), end-tidal $CO_2$ level, and VAS value in the comparison of thoracic breathing and diaphragm breathing. The results showed that breathing patterns and JPE were related to each other.

A Study about the Training Program for the Kolman Technique on the Horizontal Bars (체조 철봉 콜만 기술동작의 훈련프로그램 적용 및 향상도평가)

  • Back, Jin-Ho;Park, Jong-Chul;Yoon, Chang-Sun
    • Korean Journal of Applied Biomechanics
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    • v.19 no.1
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    • pp.37-47
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    • 2009
  • This study develops a technique training program to enhance the completion of Kolman, the high air flight technique, and applies it to two national athletes of the horizontal bar, one of the gymnastic events, for eight weeks. After that, their improvement was measured through 3D motion analysis to help them elevate their performance. The training program includes swing, hand release, twist, and bar hold, and its implementation produced the results stated below. They were made to practice the motion in the following way. After the hand-standing of giant swing which initiates the motion, they lift their body upward a little bit more. Next, they take their body down almost like a vertical descent and make a deep tap swing. Instead of doing the tap swing which widens the flection of hip and shoulder joints, while body revolution is more emphasized in particular, they release the bar as raising the centroid of their body sufficiently. During the flight, they try to narrow every joint in their body. As a result, the bar's elasticity becomes greatly increased, and since the backing rate of their body gets higher, the centripetal force of the swing is improved that they can release the bar in the higher position. In addition, because they can erect their body faster during the flight, they can perform comfortable twist and revolution in the air. They can also adjust the direction of the flight easily without too much concern for the proper timing of hand release as they rise. Thereby, they can not only maintain adequate distance from the bar for the bar hold but also ensure enough distance for body revolution and twist.

The Generation and Function of the three $\breve{U}$m and three Yang meridian (삼음삼양경맥(三陰三陽經脈)의 발생(發生)과 기능(機能))

  • Park, Chan-Guk
    • Journal of Korean Medical classics
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    • v.12 no.2
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    • pp.166-174
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    • 1999
  • Meridians are often defined as passway of Ki and Blood or something that can control funtions of the body. It is true but I think meridians have something more than that. Meridians are not just passway of Ki and Blood, rather they receive Ki from outside and transform it into Essence-Ki(精氣). If we draw a line in a body, we have Chang-Pu inside and meridians outside. Chang-Pu whim is inside our body hold Essence-Ki and manipulate it. These Chang-Pu also have variation of Ki accumulation-Tai-Yang, Soyang, T'ae$\breve{u}$m, Soum. Nevertheless, their gradients are not great so Ki flow among them are not great either. If there are much Ki flow in our body there will be much Ki consumption resulting in exhaustion of Essence-Ki, which is very hard to acquire. Therefore Chang-Pu keeps less gradient by not moving Ki a lot to preserve Essence-Ki. Chang-Pu, inside, are suitable for storing Ki while meridians, outside, are for producing Ki. Meridinas have great difference in Ki accumulation so there are great flow of Ki. This nature is suitable for producing Ki. For example, roots and limbs of a tree don't have much gradient in Ki. They are concentrated and their shape are not very distinct. On the other hand, leaves are wide and it's easy to tell front from back. It means their Ki gradient is great and their Ki flow is also great. Therefore they suitable for producing Ki. Just like this, meridians in our body are suitable for producing Ki. Areas that meridians cover are much wider than that of Chang-Pu. Four limbs and surface of our body are very distinctive. Ulnar side is high in Ki accumulation but is small in volume so it's better to store Ki there. Radial side is low in Ki accumulation but big in volume so it's better to receive and consume Ki there. Meridians are deeply involved in producing and storing Ki.

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