• Title/Summary/Keyword: Over-the-head

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Observer-Based On-Line Overload Monitoring System of PMSM (상태관측기를 이용한 PMSM의 On-Line 과부하 모니터링 시스템)

  • Jang, Ki-Chan;Suh, Suhk-Hoon;Woo, Kwang-Joon
    • Proceedings of the KIEE Conference
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    • 2001.11c
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    • pp.268-271
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    • 2001
  • This paper presents observer-based on-line overload monitoring scheme for a PMSM(Permanent Magnet Synchronous Motor) drive system. Proposed scheme is to monitor overload status of motor drive system at remote place. The drive system is previously installed on main system and has no communication function. Proposed scheme consists of intelligent sensing head and monitoring part. Intelligent sensing head acquire motor 3-Phase currents and transmit data to monitoring part over serial communication interface. Monitoring part estimates motor speed using state observer. By comparing estimated speed with reference speed, we can detect motor fault. In this scheme observed information must coded and transmitted over a digital communication channel with finite capacity. We consider communication constraint as time delay and we design discrete-time observer. The proposed scheme is tested on the actual drive system.

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Ulnar Nerve Injury Caused by the Incomplete Insertion of a Screw Head after Internal Fixation with Dual Locking Plates in AO/OTA Type C2 Distal Humerus Fractures

  • Shin, Jae-Hyuk;Kwon, Whan-Jin;Hyun, Yoon-Suk
    • Clinics in Shoulder and Elbow
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    • v.20 no.4
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    • pp.236-239
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    • 2017
  • After dual plating with a locking compression plate for comminuted intraarticular fractures of the distal humerus, the incidence of ulnar nerve injury after surgery has been reported to be up to 38%. This can be reduced by an anterior transposition of the ulnar nerve but some surgeons believe that extensive handling of the nerve with transposition can increase the risk of an ulnar nerve dysfunction. This paper reports ulnar nerve injuries caused by the incomplete insertion of a screw head in dual plating without an anterior ulnar nerve transposition for AO/OTA type C2 distal humerus fractures. When an anatomical locking plate is applied to a distal humeral fracture, locking screws around the ulnar nerve should be inserted fully without protrusion of the screw because an incompletely inserted screw can cause irritation or injury to the ulnar nerve because the screw head in the locking system usually has a slightly sharp edge because screw head has threads. If the change in insertion angle and resulting protruded head of the screw are unavoidable for firm fixation of fracture, the anterior transposition of the ulnar nerve is recommended over a soft tissue shield.

A Suspected Case of Hyperkeratotic Head and Neck Malassezia Dermatosis Presenting with Acanthosis Nigricans

  • An, Min Kyun;Yoon, Ji Ha;Cho, Eun Byul;Park, Eun Joo;Kim, Kwang Ho
    • Journal of Mycology and Infection
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    • v.23 no.4
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    • pp.111-114
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    • 2018
  • A 19-year-old woman presented with an asymptomatic cutaneous discoloration on her nape. Dermatological examination revealed localized dark brown to dark pigmented velvety macules and patches. She denied a past medical history, except for a 7-kg weight gain over a 6-months period. Histopathologically, the specimen showed hyperkeratosis, epidermal hyperplasia, mild acanthosis, and papillomatosis. In addition, keratin material and fungal spore were noted between the papilloma ridges. Periodic acid-Schiff special stain showed a positive result for the fungal spore in the horny layer. She was treated with a daily oral dose of terbinafine and topical flutrimazole. After 12 weeks of treatment, she is currently under observation without pigmentation and adverse effect. We considered the initial diagnosis as acanthosis nigricans because of weight gain, similar clinical features, and histological findings. However, the final diagnosis was hyperkeratotic head and neck Malassezia dermatosis considering the presence of yeast and the dramatic improvement after antifungal treatment. To the best of our knowledge, hyperkeratotic head and neck Malassezia dermatosis is not well characterized in the literature. It is an unusual variant of pityriasis versicolor. The skin lesion appears brown to dark, scaly, and hyperkeratotic macules and patches located on the face and neck. Here, we reported an unusual case of hyperkeratotic head and neck Malassezia dermatosis.

The Relative Incidence of Neoplastic Versus Non-neoplastic Mass in Major Salivary Gland Area Diagnosed by Surgery (주타액선부위에 발생한 종괴의 비교분석)

  • Oh Kyung-Kyoon;Chang Kyung-Man;Park Mi-Hyang
    • Korean Journal of Head & Neck Oncology
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    • v.10 no.2
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    • pp.157-162
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    • 1994
  • It is the purpose of this paper to determine the relative frequency of the neoplastic vs. non-neoplastic disease in a series of surgically removed parotid and submandibular masses. The study was conducted a retrospective review of 249 consecutive, operated patients' records seen over a 9-year period from 1985 through 1993 at Department of Otolaryngology-Head and Neck Surgery, Korea Cancer Center Hospital. One hundred and fifteen patients had parotid mass and 134 patients had submandibular mass. All the specimen surgically removed were studied histopathologically. The numbers and percentages of patients are reported along with a pathological classification of the lesions encountered: neoplastic(benign, malignant) and non-neoplastic (inflammatory, non-inflammatory). There were 59 benign, 46 malignant, 6 inflammatory, 4 non-inflammatory in 115 parotid mass, and 33 benign, 48 malgnant, 47 inflammatory, 6 non-inflammatory in 134 submandibular mass. One-hundred-eighty-six of entire 249 patients had tumor involvement, for a 74.7% incidence of neoplasia. There was a neoplastic predominance in parotid mass(91.3%) and a relative inflammatory predominance in submandibular mass(35.1%).

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A Case of Metallic Foreign Body in Maxillary Sinus (장기간 체류된 상악동 금속이물 1례)

  • Jung Dae-Gun;Lee Dong-Mok;Kim Myung-Won;Park So-Young;Kim Byung-Guk
    • Korean Journal of Bronchoesophagology
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    • v.10 no.1 s.19
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    • pp.55-57
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    • 2004
  • On occasion there were reports of foreign body of paranasal sinuses. Most common site is the maxillary sinus. But it is very rare to experience a long-term foreign body in maxillary sinus. There are two types of maxillary foreign bodies according to etiology, one is caused by various traumatic accidents, and the other is iatrogenic cause which mainly retaining gauze or medical instruments after sinus operation or teeth extraction. We experienced an interesting case of over fifty yews resided metal foreign body in maxillary sinus caused sinusitis, and report with a brief literature review.

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A Study on the Design of Linear Motor for Over Head Shuttle Short-Cut system (OHS 분기 시스템 적용을 위한 선형전동기에 관한 연구)

  • Park, Gun-Woo;Yun, Jong-Bo;Moon, In-Ho
    • Proceedings of the KIEE Conference
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    • 2009.07a
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    • pp.861_862
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    • 2009
  • 본 논문은 LCD 생산라인의 물류 자동화 시스템 중 OHS(Over Head Shuttle)을 분기가 되도록 하여, 이송 효율을 높이고, 이송거리를 단축시키기 위한 선형 이송시스템에 적용이 가능한 영구자석 여자 횡자속 선형 전동기 개발에 관한 내용이다. 3차원 FEM 해석과정특성 실험을 통해 전동기의 특성을 분석하여, 직선-곡선 레일과 분기구간에서 이송 가능한 횡자속 선형전동기 추진모듈의 사양을 결정하고 시작품을 설계, 제작하여 OHS 시스템 등의 이송시스템에 적용 가능한지 그 타당성을 검토하였다.

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Three Weekly Versus Weekly Cisplatin as Radiosensitizer in Head and Neck Cancer: a Decision Dilemma

  • Negi, Preety;Kingsley, Pamela Alice;Srivastava, Himanshu;Sharma, Surender Kumar
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.4
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    • pp.1617-1623
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    • 2016
  • Cisplatin-based concurrent chemoradiation plays an undisputed key role as definitive treatment in unresectable patients with locally advanced squamous cell carcinoma head and neck or as an organ preservation strategy. Treatment with 100 mg/m2 3-weekly cisplatin is considered the standard of care but is often associated with several adverse events. The optimum drug schedule of administration remains to be defined and presently, there is insufficient data limiting conclusions about the relative tolerability of one regimen over the other. This review addresses regarding the optimal dose schedule of cisplatin focusing mainly on three-weekly and weekly dose of cisplatin based concurrent chemoradiotherapy in locally advanced head and neck cancer with an emphasis on mucositis, dermatitis, systemic toxicity, compliance, and treatment interruptions. To derive a definitive conclusion, large prospective randomized trials are needed directly comparing standard 3-weekly cisplatin ($100mg/m^2$) with weekly schedule ($30-40mg/m^2$) of concurrent cisplatin based chemoradiotherapy in locally advanced squamous cell carcinoma head and neck.

Computation of Temperature Rising by Absorbed Power Radiated from a Portable Phone (휴대폰 전파인 인제 흡수전력량과 온도 상승량 산출)

  • 이승학;김채영;강승진
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.12 no.3
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    • pp.409-426
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    • 2001
  • Absorbed power of the human head radiated from a 900 MHz portable phone and temperature rise are computed using FDTD(Finite-Difference Time-Domain) method. For this computation the 5 layered media for the human head modeling and the monopole antenna attached to metallic box for the portable phone are used. To reflect the real circumstances typical sizes of human heads and portable phones are considered in the calculation. The length of monopole antenna is 8.15 cm, and the output power of a phone is 600 mW. Under the predetermined model the distribution of 1 g, 10 g averaged SAR and temperature rise rate over the human head are calculated, from which it was found that the position of maximum SAR is near at the head skin surface, not deep places far into the head. The position of the highest temperature is located far from the head skin more than that of the maximum SAR occured. The averaged SAR and temperature along the distance between the head and phone are calculated according to seperation distance between the head and phone.

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A Study on Comparison of the Darcy-Weisbach and Hazen-Williams Equation (Darcy-Weisbach와 Hazen-Williams Equation 비교 연구)

  • Kim, Tae-Kyoungi;Rhee, Kyoung-Hoon;Sun, Byoung-Jin;Chio, Cheong-Ho
    • Journal of Korean Society of Water and Wastewater
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    • v.21 no.4
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    • pp.421-428
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    • 2007
  • Many engineering problems on the pipeline flow use continuity, energy, friction loss head equation. To calculate friction loss head in a pipeline, Darcy-Weisbach and many average velocity equations can be used and Hazen-Williams equation is used frequently in the pipe network for the water supply systems. Darcy-Weisbach equation is a general one acquired from applying Bernoulli's equation in the pipeline flow and Hazen-Williams equation is a experimental one in case that pipe velocity is below 3m/sec and pipe diameter is over 50mm. In this study, comparing Darcy-Weisbach with Hazen-Williams equation, relation f and C that are expressed as roughness coefficients of those equations is explained. Next, head losses calculated from using those equations are compared and those are applied in realistic pipelines. Comparing f with C, the f is decreasing linearly according to increase of the Reynolds number Re and increasing in case the C is decreasing. additionally, the C is increasing up to a point and then is decreasing according to increase of the Re. Next, the C is increasing and Re's range for increase of the C lengthens in case of decreasing of the relative roughness ${\varepsilon}/d$. Comparing head losses acquired from the two equations, head loss appears large in case that the C is decreasing and the ${\varepsilon}/d$ is increasing. additionally, Head loss calculated by the Darcy-Weisbach equation varies larger than one by Hazen-Williams equation in regard of the Re. Next, change aspect of head loss acquired by the C is distinguished more clearly than the one by the ${\varepsilon}/d$.

Clinical Characteristics of Head and Neck Mucosal Melanoma (두경부에 발생한 점막형 악성흑색종의 임상적 특성)

  • Choi Jong-Ouck;Seok Youn-Sik;Choi Geon;Yoo Hong-Kyoun
    • Korean Journal of Head & Neck Oncology
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    • v.12 no.2
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    • pp.188-192
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    • 1996
  • The biological behavior of mucosal melanoma is aggressive with frequent local recurrence and distant metastasis owing to the abundantly surrounding blood vessels and lymphatics adding to the fact that diagnosis is frequently delayed due to non-specific clinical outcome. The management for mucosal melanoma of the head and neck is controversial in view of the poor prognosis. Ten cases treated over the past 10 years are reported. The average age of the patients was 54.4 years. Seven cases were localized in the nasal cavity and paranasal sinuses and three cases in the oral cavity and nasopharynx. Eight patients had local tumors, one had regional lymph node metastases and one hed lung metastases. Six patients underwent surgical resection, with postoperative radiotherapy in five patients, three patients received radiotherapy and one patient received combination therapy. Recurrence occured in 80% of the patients and the median time to recurrence was 10.5months. The median survival for those who received surgical resection followed by postoperative radiation therapy was 20.8 months and 14.7 months in the radiation therapy only treated group. The author's conclusion is that mucosal melanoma is a highly aggressive disease of the upper respiratory tract in which the best treatment modality is wide surgical resection followed by postoperative radiation therapy.

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