• Title/Summary/Keyword: Tightness

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Nonlinear Analysis of Rubber Bellows for the High Speed Railway Vehicle (고속철도차량 갱웨이 벨로우즈의 비선형 해석)

  • Kang, Gil-Hyun;Kim, Chul-Su
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.14 no.8
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    • pp.3631-3637
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    • 2013
  • Gangway bellows in this study is the double wrinkled neoprene rubber component to accept various deviations between the carriage end parts of the articulated type high speed railway vehicle(HSRV). The fatigue failure of the bellows has a harmful effect on the riding comfort for the passengers with the increase of noise and ringing in the ears due to air-tightness failure during pass through a long tunnel. In this study, to assure the safety of gangway bellows of the HSRV, non-linear analysis of the gangway bellows considering triaxial angular displacement(rolling /yawing/pitching) between the carriage end parts are performed. The non-linear properties of the rubber are determined by uniaxial tension and equi-biaxial tension test. Moreover, from the results of non-linear analysis, the effects of the angular displacements and frictional coefficients are evaluated.

Stochastic Glitch Estimation and Path Balancing for Statistical Optimization (통계적 최적화를 위한 확률적 글리치 예측 및 경로 균등화 방법)

  • Shin Ho-Soon;Kim Ju-Ho;Lee Hyung-Woo
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.43 no.8 s.350
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    • pp.35-43
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    • 2006
  • In the paper, we propose a new method for power optimization that uses path balancing based on stochastic estimation of glitch in Statistical Static Timing Analysis (SSTA). The proposed method estimates the probability of glitch occurrence using tightness probability of each node in timing graph. In addition, we propose efficient gate sizing technique for glitch reduction using accurate calculation of sizing effect in delay considering probability of glitch occurrence. The efficiency of proposed method has been verified on ISCAS85 benchmark circuits with $0.16{\mu}m$ model parameters. Experimental results show up to 8.6% of accuracy improvement in glitch estimation and 9.5% of optimization improvement.

Cervical stabilization exercise using the Sling system (슬링(Sling) 시스템을 이용한 경부 안정화 운동)

  • Kwon, Jae-Hoak;Cho, Mi-Ju;Park, Min-Chull;Kim, Suhn-Yeop
    • The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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    • v.8 no.2
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    • pp.57-71
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    • 2002
  • Cervical pain is a rapid increase that is owing to a flexion-extension whiplash injury, unappropriated posture, chronical repetition injury from abdominal position of head and neck, excessive repeating work, chronical deficiency of excercise. Because of that is bring about muscle unbalance, tightness of cervical extensor muscle, weakness of cervical deep flexor muscles, instability of cervical region and reduction of proprioceptive sensor. Recent the role of muscle is more emphasized for preservation of sine stabilization. And cognition of integrated muscular system, importance for the operation and relation is increased to maintain stability of the motor system and pertinent function. Therefore we are going to introduce the sling exercise and stabilization exercise method for advanced efficient of cervical and upper limb and for the muscle strengthening to importance cervical stabilization through neurological program as control the reaction of cervical stabilization. Sling exercise therapy(SET) concept consists of a system of diagnosis and treatment. The system of diagnosis involves testing the muscle's tolerance through progressive loading in open and close kinetic chains. The SET system contains elements such as relaxation, increasing the range of movement, traction, training the stabilizing musculature, sensory-motor exercises, training in open and close kinetic chains, dynamic training of the mobilizing musculature, cardiovascular exercise, group exercise, personal exercise at home Sensory-motor training is an essential element of the SET concept. The emphasis is on closed kinetic chain exercise on an unstable surface, there by achieving optimum stimulation of the sensory-motor apparatus.

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The Individual Heat-recovery ventilation system of Residential Buildings (주거용 건물의 개별 환기시스템 필요성에 관한 연구)

  • Shin, U-Cheul;Lee, Wang-Je;Yoon, Jong-Ho;Baek, Nam-Choon
    • KIEAE Journal
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    • v.14 no.6
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    • pp.99-104
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    • 2014
  • Recently supply of low energy house is increasing which can enhance energy efficiency and indoor environment comfort. Low energy house have to secure air tightness as well as thermal performance so house become high airtightness and inevitably need heat recovery ventilator to enhance indoor air quality. However, most of current ventilation systems are one-click, controlling the entire space so it causes increasing of heating load and fan power which makes it hard to save energy. Thus, Individual Control system is required which can achieve both enhancing indoor air quality and decreasing heating load and electric fan power. Thereby, in this study, we analyzed the correlation between ventilation and fan power through mock-up experiment and measured ventilation load under individual control system. As a result, under the condition of $24^{\circ}C$ of indoor temperature for 6 month(November to April) in Daejeon, ventilation load by fan speed was $10.9{\sim}19.6kWh/m^2{\cdot}a$ when operated 24 hours and $7.6{\sim}13.7kWh/m^2{\cdot}a$ when operated 12 hours in night time. In addition, it is possible to reduce at most 60% of ventilation load under the individual control system; measured ventilation load was $7.4kWh/m^2{\cdot}a$ when operated 24 hours, and $5.5kWh/m^2{\cdot}$ when operated 12 hours in night time.

The Energy Analysis and Evaluation of the NEO-Hanok

  • Han, Sang Hee;Park, So Yeon;Park, Hyo Soon
    • KIEAE Journal
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    • v.14 no.2
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    • pp.77-86
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    • 2014
  • Plenty of efforts have been made in the traditional architecture of Korea, Hanok, to develop various elements such as restoration, the introduction of new design, and energy-saving while systemic setups on standard and evaluation of eco-friendly energy design of Hanok are lacking. If we evaluate energy performance based on current standards without reflecting unique features of Hanok on the system, Hanok will be included in the very low grade among the residential buildings being included in the approval system of eco-friendly architecture or the unique features will be modified and the burden of increased construction cost. Therefore, this study is to prepare the basic reference for the introductory evaluation system by evaluating the energy performance level of NEO-Hanok based on the current building energy rating system. The result for NEO-Hanok based on the building energy rating system, we propose the rating standard with scorecard elements of NEO-Hanok by considering the necessity of identity and standard for NEO-Hanok. As a result of infiltration test to check the tightness, it was measured as 10.81 times/h (50 ACH). As we switch from the main insulation for the wall from the glass wool 64k(0.035W/mk) to rigid polyurethane foam first class first unit (0.024W/mk), the result was slightly increased from the first demand quantity rating yield $249.8kWh/m^2{\cdot}yr$ to $235.0kWh/m^2{\cdot}yr$. Current certificate system is focused more on the heating load than the cooling load, it is disadvantageous for Hanok, which has less cooling energy consumption in summer. The rating result from the target building study is level 4.

A Comparative Analysis on Cooling Energy of Heat Recovery Ventilator and Air Handling Unit in the Office Building (사무용 건물에서 전열교환 환기시스템과 일반공조기의 냉방에너지 비교분석에 관한 연구)

  • Jang, Ji-Hoon;Kim, Hyeonsoo;Auh, Jin-Sun;Leigh, Seung-Bok;Kim, Byungseon-Sean
    • KIEAE Journal
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    • v.16 no.6
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    • pp.123-128
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    • 2016
  • Purpose: In order to save the energy consumption of buildings, buildings have been constructed with high performance insulation or airtightness. However, high performance insulation or air tightness has led to a poor indoor air quality. Therefore, HRV(Heat Recovery Ventilator) has received attention to save the energy consumption and insure a good air quality. Because existing research is almost about the performance of HRV in residential buildings, This study analyzed the effect of HRV on cooling energy consumption in commercial office building. Method: This study was proceeded at commercial office building in In-cheon. In order to evaluate the energy consumption of HRV, this study proposed two methods: estimating energy consumption of the room installed AHU(Air Handling Unit) system; estimating energy consumption of the room installed HRV system. Therefore, comparison of two methods was proceeded to evaluate energy performance of each method. Result: As the result of comparison between rooms installed AHU and HRV, the experiment showed that energy consumption of the room installed HRV system is about 22% less than the room of AHU system. This conclusion is considered because the room installed HRV system have maintained temperature well at set point temperature $26^{\circ}C$.

SURGICAL CORRECTION OF A CUPID'S BOW USING A DOUBLE Z-PLASTY: REPORT OF A CASE (중복 Z-성형술을 이용한 큐피드활의 교정)

  • Ryu, Sun-Youl;Seo, Il-Young
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.27 no.1
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    • pp.66-70
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    • 2005
  • Cupid's bow, upper lip, columella, and ala of nose are esthetically important, in which their symmetrical plasties determine success or failure of the surgery in cleft lip and palate patients. Z-palsty and its modifications are simple and effective. The double Z-plasty is economical in surgical time and esthetics in reconstructing the cupid's bow compared with other methods. We report a 29-year-old male patient who represented reversed cupid's bow and whistle deformity after the primary repair of the cleft lip. He was corrected the cupid's bow using a double Z-plasty. The reversed cupid's bow was corrected to a normal shape and the whistle deformity disappeared. The tightness of the upper lip was relieved after the operation. The double Z-plasty was esthetically successful because the procedure was limited in the vermilion and did not produce a new scar on the skin. Furthermore, the lip tubercle became protuberant. The cupid's bow was symmetrically smoothly curved at 4 years after the operation. These results indicate that the double Z-plasty is simple, less traumatic to the surrounding tissues, and suitable for the correction of whistle deformity.

Forehead reconstruction with a custom-made three-dimensional titanium implant in a Parry-Romberg syndrome patient

  • Kim, Jae Yoon;Jung, Bok Ki;Kim, Young Suk;Roh, Tai Suk;Yun, In Sik
    • Archives of Craniofacial Surgery
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    • v.19 no.2
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    • pp.135-138
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    • 2018
  • Parry-Romberg syndrome is a rare neurocutaneous syndrome characterized by progressive shrinkage and degeneration of the tissues usually on only one side of the face. It is usually difficult to restore the facial contour due to skin tightness. In this case report, we report a forehead reconstruction with custom-made three-dimensional (3D) titanium implant of a Parry-Romberg syndrome patient who was treated with multiple fat grafts but had limited effect. A 36-year-old man presented with hemifacial atrophy. The disease progressed from 5 to 16 years old. The patient had alopecia on frontal scalp and received a surgery using tissue expander. The alopecia lesion was covered by expanded scalp flap done 22 years ago. Also, he was treated with fat grafts on depressed forehead 17 years ago. However, it did not work sufficiently, and there was noted depressed forehead. We planned to make 3D titanium implant to cover the depressed area (from the superior orbital rim to the vertex). During the operation, we confirmed that the custom-made 3D implant accurately fit for the depressed area without any dead spaces. Previously depressed forehead and glabella were elevated, and the forehead contour was improved cosmetically. A custom-made 3D titanium implant is widely used for skull reconstruction and bring good results. In our case, the depressed forehead of a Parry-Romberg syndrome patient was improved by a 3D titanium implant.

A Study on Formality and Symbolism in Black Dress (흑색의상의 조형성과 상징성에 관한 연구)

  • 곽혜선;금기숙
    • Journal of the Korean Society of Costume
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    • v.37
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    • pp.231-252
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    • 1998
  • Since the costume directly express human mental and emotional status, colors of costume can be valuable data to grasp the spirit of the times. Black is noticeably used in modern fashion and the study for black costume is very useful to understand modern fashion. There-fore the study mainly approaches the black costume, finding its background of appearance and symbolism, reviews the symbolism and formality of black expressed in the field of paint-ing and design beyond the fashion, and compar-es to fashion. The study result of the thesis is as follows ; First, black as a color is a one to light other neighboring colors, while it is a static, con-tractible and outstandigly attractived color. Second, black color traditionally symbolizes death, earth, air, North and inferior level and in the painting, it symbolized death, despair, fantastic world and the expression of pent-up self, while cities have been symbolized in the black printing in modern times. In the design, black has appeared with the industrial society, which symbolizes functionality and modernity. Third, black in the fashion design was symbolized death, sternness simplicity, modernity, sex, resistance and so on. Death became conspicious by a religious factor since the old times, sternness was influenced by Spanish fashion in the 16th century, simplicity by Dutch fashion in the 17th century and modernity by Baudelaire dandyism and Chanel little black dress, while sex and resistance were urged to the modern times by teenage inferior culture and stickiness to sex. Fourth, the formative features of black costume prefer simplicity, tightness and bareness in form, and in material, usually used glancing materials changed by the effect of light, lace, see-through fabric and matte one with depth. As a result, the black color is summarized to symbol death, expression of self and modernity. It is not a color of emotion but of mentality and artificial one against nature. Black color in fashion gets a strong power to express self in the symbolic aspect and draws a higher attention on human body than the fashion itself. By these features, black costume will be continuously prefered in spite of changes of the fashion.

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Active monitoring of pipeline tapered thread connection based on time reversal using piezoceramic transducers

  • Hong, Xiaobin;Song, Gangbing;Ruan, Jiaobiao;Zhang, Zhimin;Wu, Sidong;Liu, Guixiong
    • Smart Structures and Systems
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    • v.18 no.4
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    • pp.643-662
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    • 2016
  • The monitoring of structural integrity of pipeline tapered thread connections is of great significance in terms of safe operation in the industry. In order to detect effectively the loosening degree of tapered thread connection, an active sensing method using piezoceramic transducers was developed based on time reversal technique in this paper. As the piezoeramic transducers can be either as actuators or sensors to generate or detect stress waves, the energy transmission for tapered thread connection was analyzed. Subsequently, the detection principle for tapered thread connection based on time reversal was introduced. Finally, the inherent relationship between the contact area and tightness degree of tapered thread connection for the pipe structural model was investigated. Seven different contact area scenarios were tested. Each scenario was created by loosening connectors ranging from 3 turns to 4.5 turns in the right tapered threads when the contact area in the left tapered threads were 4.5 turns. The experiments were separately conducted with a highly noisy environment and various excitation signal amplitudes. The results show the focused peaks based on time reversal have the monotonously rising trend with the increase of the contact areas of tapered threads within an acceptable monitoring resolution for metal pipes. Compared with the energy method, the proposed time reversal based method to monitor tapered threads loosening demonstrates to be more robust in rejecting noise in Structural Health Monitoring (SHM) applications.