• 제목/요약/키워드: Short leg

검색결과 173건 처리시간 0.022초

Influence of Tether Length in the Response Behavior of Square Tension Leg Platform in Regular Waves

  • El-gamal, Amr R.;Essa, Ashraf
    • International Journal of Ocean System Engineering
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    • 제4권1호
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    • pp.19-28
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    • 2014
  • The tension leg platform (TLP) is a vertically moored structure with excess buoyancy. The TLP is regarded as moored structure in horizontal plan, while inherit stiffness of fixed platform in vertical plane. In this paper, a numerical study using modified Morison equation was carried out in the time domain to investigate the influence of nonlinearities due to hydrodynamic forces and the coupling effect between surge, sway, heave, roll, pitch and yaw degrees of freedom on the dynamic behavior of TLP's. The stiffness of the TLP was derived from a combination of hydrostatic restoring forces and restoring forces due to cables and the nonlinear equations of motion were solved utilizing Newmark's beta integration scheme. The effect of tethers length and wave characteristics such as wave period and wave height on the response of TLP's was evaluated. Only uni-directional waves in the surge direction was considered in the analysis. It was found that for short wave periods (i.e. 10 sec.), the surge response consisted of small amplitude oscillations about a displaced position that is significantly dependent on tether length, wave height; whereas for longer wave periods, the surge response showed high amplitude oscillations about that is significantly dependent on tether length.

Copepods of the Family Artotrogidae (Siphonostomatoida) from Korea, with Descriptions of Eight New Species

  • Jimin Lee;Il-Hoi Kim
    • Animal Systematics, Evolution and Diversity
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    • 제39권4호
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    • pp.176-211
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    • 2023
  • Nine copepod species of the family Artotrogidae Brady, 1880 are described or redescribed from Korea. Included new species are two in the genus Artotrogus Boeck, 1859, one each in the genera Bradypontius Giesbrecht, 1895, Cryptopontius Giesbrecht, 1899, Neopontius Scott T., 1898 and Chejupontius n. gen., and two in the genus Sewellopontius Ummerkutty, 1966. Chejupontius n. gen. resembles Ascidipontius Kim I. H., 1996, Pulicitrogus Kim I. H., 1998, and Sewellopontius in having reduced armature of leg 1, but is distinguished from these and other genera of the family by the large, mediodistally expanded protopod of leg 5 and by a combination of characters exhibited in leg 1 that the first exopodal segment lacks an inner seta, the second exopodal segment lacks an outer spine, the third exopodal segment is armed with three spines plus one to three setae, and the second endopodal segment is armed with a single inner seta. Pteropontius cristatus Giesbrecht, 1895 known previously only from the Mediterranean Sea is redescribed, based on a newly collected specimen from Korea, and P. trimerus Kim I. H., 1996 is removed to the genus Sewellopontius. A short note is given for the epibiotic suctorian Thecacineta calix (Schroder, 1907) which was found attached to the antennule of a new copepod species.

PWM 인버터의 전류파형 개선에 관한 연구 (Current Waveform Improvement of PWM Inverter)

  • 장석주;조상환;설승기
    • 대한전기학회논문지
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    • 제39권3호
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    • pp.273-280
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    • 1990
  • To prevent the shoot-through phenomena in a PWM inverter, a short dead time is usually provided between a pair of switching transistors in the same leg of the inverter. In this approach, the amount of the dead time is designed to meet the worst case condition of the inverter transistors and the base drive elements. So, in normal cases, relatively large portion of the dead time is unnecessary and it results in an undesirablecurrent waveform distortion and generates ripple torque on the motor shaft. In this paper, a new base drive method to remove the undesirable portion of the dead time is described. The method senses the transistor on/off states to interlock the other transistor of the leg without the external dead time. Also, for the transistors of large current rating, the Darlington drive circuit is combined to the proposed method and is tested to verify the effectiveness. The experimental results of the proposed method are described and compared with those of the conventional dead time method.

비만 여성의 하반신 체형 유형화에 관한 연구 (A Study on Lower Bodyshape from Classification of Obese Women)

  • 이진희
    • 한국의류학회지
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    • 제24권2호
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    • pp.237-244
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    • 2000
  • This study was carried out on 91 obese women who satisfied both of the conditions for obesity: over 1.6 in Rohrer index and over 90cm in bust girth. The purpose of this study was to analyze and classify the lower body of obese women and find out their respective characteristics. Twenty seven measurement items(21 direct measurement items and 6 indirect measurement items) were used for factor-analysis and cluster-analysis. In the study of lower body type, 7 factors were as a result of factor analysis and those factors were comprise 75.9% of total variance. Lower bodyshape were classified 3 types according to the cluster analysis. Type 1 was protrude of the hip, type 2 was short leg and protrude of the abdominal region and type 3 was obese of hip and long leg.

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The Effects of Simulated Mild Leg Length Discrepancy on Gait Parameters and Trunk Acceleration

  • Jung, Soo-jung;An, Duk-hyun;Shin, Sun-shil
    • 한국전문물리치료학회지
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    • 제25권4호
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    • pp.9-18
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    • 2018
  • Background: Leg length discrepancy (LLD) leads to many musculoskeletal disorders and affects daily activities such as walking. In the majority of the population, mild LLD is a common condition. Nevertheless, it is still controversy among researchers and clinicians on the effects of mild LLD during gait, and available studies have largely overlooked this issue. Objects: The purpose of the present study is to investigate the effects of mild LLD on the gait parameters and trunk acceleration. Methods: A total of 15 female and male participants with no evidence of LLD of >.5 ㎝ participated in the present study. All participants walked under the following two conditions: (1) The non-LLD condition, where the participants walked in shoes of the same heel height; (2) A mild LLD condition induced by wearing a 1.5 ㎝ higher heel on the right shoe. The GAITRite system and tri-axial accelerometer were used to measure gait parameters and trunk acceleration. To compare the variation of each variable, a paired t-test was performed. Results: Compared to the non-LLD condition, step time and swing phase were significantly increased in the mild LLD condition, while stance phase, single support phase, and double support phase significantly decreased in the short limb (p<.05). In the long limb of the mild LLD condition, single support phase significantly increased, while swing phase significantly decreased (p<.05). Furthermore, significant decrease in the gait velocity and cadence in the mild LLD condition were observed (p<.05). In the comparison between both limbs in the mild LLD condition, the step time and swing phase of the short limb significantly increased compared with the long limb, while step length, stance phase, and single support phase of the long limb significantly increased compared with the short limb (p<.05). Additionally, trunk acceleration of all directions (anterior-posterior, medial-lateral, vertical) significantly increased in the mild LLD condition (p<.05). Conclusion: The results of the present study demonstrate that mild LLD causes altered and asymmetrical gait patterns and affects the trunk, resulting in inefficient gait. Therefore, mild LLD should not be overlooked and requires adequate treatment.

보조회로도 영전압영전류스위칭하는 DC-DC 변환기 (A Fully Soft Switched Full Bridge DC-DC converter)

  • 전성즙;조규형
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1999년도 하계학술대회 논문집 F
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    • pp.2512-2514
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    • 1999
  • A new zero voltage and zero current switching(ZVZCS) full bridge DC-DC converter with transformer isolation is proposed for arc welding machines. The proposed DC-DC converter uses an auxiliary transformer to obtain ZCS for leading leg, which provides load current control capability even in short circuit condition. The auxiliary circuit also operates in ZVZCS mode. The power rating of the auxiliary transformer is about 10% of the main transformer. The operation is verified by experiments for 12[KW] prototype.

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비골 외과 절제술을 통한 족관절 또는 경골거골종골간 관절고정술 (Transfibular Approach for Ankle and Tibiotalocalcaneal Arthrodesis)

  • 정영기;유정한;박용욱;김진섭;표동철
    • 대한족부족관절학회지
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    • 제1권1호
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    • pp.15-22
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    • 1997
  • A variety of surgical approach for ankle and tibiotalocalcaneal arthrodesis has been described. We used a transfibular approach between the sural nerve and lateral branch of the superficial peroneal nerve. This permits excellent visualization of the ankle and subtalar joint so that the fusion can readily be achieved under the direct visualization. Eight ankle fusions and four tibiotalocalcaneal fusions were carried out through a transfibular approach and reviewed. The resected fibula was utilized for bone graft. The follow up period was from 12 to 22 months. Ages of the patients ranged from 27 to 58 years. The postoperative regimen was six weeks nonweight bearing in a short leg cast, followed by weight bearing in a short leg cast until union occurred. All cases were fused except one who had preoperative pyogenic arthritis of the ankle and hindfoot. The results were as follows; 1. The chance of incisional neuroma is lessened through incision between the sural nerve and superficial peroneal nerve. 2. The possibility of a skin slough is reduced by using full thickness skin flaps. 3. Excellent visualization of the ankle and subtalar joint is easily achieved. So, we believed that the transfibular approach for ankle and tibiotalocalcaneal arthrodesis is the excellent surgical approach.

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휠체어 장애인의 대량맞춤복을 위한 사이즈 체계 개발: 남성 정장 사이즈 (Development of a Sizing System of Mass-customized Clothing for Wheelchair Users: Men's Suit Sizes)

  • 박광애;박장운;양정은;전은진;유희천
    • 한국의류산업학회지
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    • 제16권4호
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    • pp.625-634
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    • 2014
  • This study develops a sizing system of mass-customized male suits for wheelchair users. One hundred and three male wheelchair users' 21 anthropometric dimensions were measured to identify body shapes and develop a sizing system. The measured wheelchair users' body sizes were compared with the average body sizes of Korean males from the $6^{th}$ Korean Body Size Survey to understand the body size differences between two groups. As a result of body shape classification using the KS's Drop method, wheelchair user body shapes were classified into four shapes for upper-body (A: 32%, B: 26%, BB: 24%, and Y: 18%), and two shapes for lower-body (B: 70% and A: 30%). The upper-body of wheelchair users was relatively developed than Korean males; however, the lower-body was relatively stunted. The key dimensions of a sizing system were selected as chest circumference, waist circumference, and trunk length, outside leg length based on the correlation analysis between anthropometric measures. The top sizes were determined considering chest and waist circumferences for horizontal sizes, and additionally the trunk length was divided into short, medium, and long groups for vertical sizes. The bottom sizes were selected considering the waist and hip circumferences for horizontal sizes, and additionally their outside leg length was divided into short, medium, and long groups for vertical sizes.

조선전기 출토 여성복식의 유형과 특징에 관한 연구 (A Study on the Types and Characteristics of Women's Costume Excavated in the Early Joseon Dynasty)

  • 정주란;김용문
    • 복식
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    • 제67권1호
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    • pp.147-168
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    • 2017
  • This study examines the types and characteristics of women's garments excavated in the early Joseon Dynasty before 1592. The study sorts out headgear, jacket, skirt and trousers, and coats from the historical texts in the early Joseon Dynasty and excavated women's wears in the fifteenth and sixteenth centuries, and analyzes their textiles and patterns. The Joseon women's garments convey several features. They are wide across the chest and square shaped collar with virtually straight sleeves. While their breast-ties are extremely little for the size of clothes, they do not have any inner-tie. They have broad and short dongjeongs which seem to be hard to be adjusted. There are a variety of headgear. Jang-Jeogori slit down in both sides. The Jeogori after the seventeenth century transformed a more practical form of a fitting dress to an individual body in comparison with the sixteenth jeogori. It is identified that the fabrics in the early Joseon period were woven more diversely and colorfully than the late Joseon period. Most of the excavated fabrics in the sixteenth century were in silk. Materials for adornments before 1592 were not much diverse and their designs mostly contained patterns of lotus flowers, patterns of cloud and treasures with oblique lines. The colors are mainly brown, navy and green. The Joseon women's clothes were comprised of skirts with folded hem, coat with round collars, wide leg pants, Jangot, long-sleeved coat with folding collars, and quadrangular pieces of cloth in various sizes, or mu and so forth. Joseon women's clothes, like men's wears, partake of active functions in their headgears, wide leg pants, styles in short front and long back, and coat with round collars.

족근-중족 관절 골절 탈구의 치료경험 (Treatment for Tarsometatarsal Fracture-Dislocation)

  • 정영기;유정한;박용욱;노동근;하성한
    • 대한족부족관절학회지
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    • 제1권2호
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    • pp.112-118
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    • 1997
  • Tarsometatarsal fracture-dislocation is uncommon but severe lesion. Since this lesion is sometimes difficult to recognize by roentgenography, it is easily overlooked. Three patients were treated with open reduction and internal fixation with 3.5 mm cannulated screw and K-wire, two had treatment with open reduction and internal fixation with 3.5 mm cannulated screw only and two had treatment with dosed reduction and short leg cast only between January 1994 and May 1996. The duration of follow-up ranged from twelve to twenty-nine months after the diagnosis. Results were assessed by a subjective questiormaire, physical examination, and radiographic analysis. Multiple fixation techniques for maintaining the reduction of tarsometatarsl joint have been introduced. We recent]y used the 3.5 mm cannulated screw for internal fixation of the tarso-first and second metatarsal fracture-dislocation. We think cannulated screw fixation has several advantages; 1. The cannulated screw fixation is more rigid than the K-wire fixation. 2. There is an decreased risk of screw breakage with early weight bearing. 3. It is possible to compress the involved joints, if necessary. There were no disability in all patients. One patient who was treated with delayed open reduction and internal fixation with 3.5 mm cannulated screw and K-wire had a radiographic mild degenerative arthritis. And one patient who was treated with dosed reduction and short leg cast had a mild metatarsus adductus. But. these two patients were symptom free. There was no correlation between the severity of the diastasis and the patient s functional result.

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