• Title/Summary/Keyword: protector

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A Study on the Improvement of Technical Regulation for Overvoltage Performance of Telecommunication Protector in Customer Premises (구내 통신용 보호기의 과전압 제한 성능 기준 개선 연구)

  • Ko, Hong-nam;Choi, Mun-Hwan;Cho, Pyung-Dong
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2013.10a
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    • pp.823-826
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    • 2013
  • Subscriber Protector is installed in a point of connection between main wire and in-plant cable to protect telecommunication facilities and service users from overvoltage or overcurrent due to the lightning or induction. In Korea, there are regulations for obligation of installation and performance criteria of protectors, but these regulations in force can not cope with diversification of services because it stands on the basis of PSTN service only. In earlier paper, we suggested the improvement way of technical regulation for subscriber protector in customer premises. and in this paper, we propose revised criteria for overvoltage performance of protector in customer premises, and make feasibility of revised criteria through inspection tests.

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Design and Evaluation of a Knee Protector using a 3D Printing Pad (3D 프린팅 패드를 활용한 무릎 보호대의 설계 및 평가)

  • Xi Yu Li;Jung Hyun Park;Jeong Ran Lee
    • Fashion & Textile Research Journal
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    • v.25 no.2
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    • pp.221-229
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    • 2023
  • This study aims to develop knee protectors that provide high safety and fitness, while incorporating a motion-adaptable 3D-printed pad. These protectors were evaluated by individuals who experience knee discomfort or pain. The results are as follows. First, the 3Dprinted pad design of a hexagonal mesh structure, which is modeled for excellent appearance and knee movement. Each unit of the mesh has a outer layer of 2mm thick, a spacer layer of 1 mm in diameter, and is connected by a 1.5 mm bridge. The bridge was extended up to 1.2 cm. Second, the knee brace was designed in three types - cylinder, strap, and combination by Universal design. Impact protection measurements of the three knee protectors demonstrated roughly 80% reduction in impact. Third, based on usability evaluation, cylinder type protectors have the highest ratings in most areas, primarily because of their ease of use. The strap type protector received positive reviews in terms of appearance and care, and the combination type provided stable knee protection. This study demonstrated the potential industrial application of 3D printing technology by designing and evaluating protective products for the human body. The results of this study are expected to aid knee protector manufacturers in developing practical products and promoting the development of protective equipment for other body parts or purposes.

Effect of Operative Wound Protection on Surgical Wound Complications (수술 증 절개창 보호 방법이 수술 후 절개창 합병증에 미치는 영향)

  • Lim, Jin-Hong;Kim, Sung-Soo;Choi, Won-Hyuk;Oh, Sung-Jin;Hyung, Woo-Jin;Choi, Seung-Ho;Noh, Sung-Hoon
    • Journal of Gastric Cancer
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    • v.7 no.4
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    • pp.248-253
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    • 2007
  • Purpose: Surgical wound complications remain a cause of morbidity and mortality among postoperative patients, and the cost of caring for patients with a surgical wound complication is substantial. The purpose of this study was to evaluate the ability of a vinyl wound protector to reduce the rate of wound complications when used in clean-contaminated surgery. Materials and Methods: Between May 2006 and September 2006, 295 patients with a gastric cancer that underwent gastric surgery were studied prospectively, and the patients were randomized into one of two groups: the no wound protector group (n=137) or the polyethylene protector group (n=132). Results: The demographics and operation type and operation time were similar for patients in both groups. The rate of wound complication was different between patients in the no protector group (n=42) and the polyethylene protector group (n=12) (P=0.001) and the rates of seroma (P=0.001), infection (P=0.030) and dehiscence (P=0.282) were different for the two groups. The postoperative hospital stay was significantly shorter in the polyethylene protector group of patients (P=0.040). Conclusion: The use of a polyethylene protector resulted in a reduction of the surgical wound complication rate, and the cost of caring for patients, and morbidity and mortality among postoperative patients could be reduced.

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Sensorless Position Control of DC Motor for the Auxiliary Scaffolding (차량용 보조발판의 센서리스 직류전동기 위치 제어)

  • Lee, Dong-Hee
    • The Transactions of the Korean Institute of Power Electronics
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    • v.24 no.6
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    • pp.389-395
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    • 2019
  • This paper presents the sensorless position control of an auxiliary scaffolding step system for vehicles using DC motors. The designed auxiliary scaffolding step has a mechanical protector at the stop position. At this position, the scaffolding is forcibly stopped by the mechanical protector, and the motor current is dramatically increased to the stall current of the DC motor, thereby increasing the electrical damage. In this study, the estimated back EMF- and current model-based observers are proposed to estimate the motor speed and stop position. A simple V/F acceleration voltage pattern is used to operate the auxiliary scaffolding system. The estimated moving position is adopted to determine the stop position of the DC motor with the load current state. The operating current of the DC motor can be reduced by the estimated moving position and V/F acceleration pattern. At the stop position, the proposed sensorless position controller can smoothly stop the DC motor with the estimated moving position and reduced load current without any mechanical and electrical stress from the stall current from the mechanical protector. The proposed control scheme is verified by the comparison of simulations and experiments.

Relation of necessity of the first aid education and attitude about traumatic dental injuries in some military men (일부 군인들의 치아외상에 대한 태도와 응급처치 교육필요성과의 관련성)

  • Kim, Yun-Jeong;Kim, Seon-Young;Shin, Dong-Min
    • Journal of Korean society of Dental Hygiene
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    • v.13 no.1
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    • pp.122-128
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    • 2013
  • Objectives : The purpose of this study was to investigate the traumatic injuries by first aid education and mouth protector in some military men. Methods : Among 195 military men, a total of 164 military men filled out the self-administered questionnaire and the return rate was 84.1%. The data were evaluated statistically using chi-square analysis. Results : 81.5% of respondents agreed that first aid education is necessary and 48.2% of respondents agreed that mouth protector of is necessary. In managing tooth fracture, subluxation, and avulsion, the military men answered the necessity of the first aid education revealed 87.2%, 86.8%, and 91.5%, respectively. The questions in managing tooth fracture, subluxation showed that mouth protector is necessary 56.3%, 49.0% respectively. In managing tooth fracture with reattachment, the necessity of the first aid education showed 88.9%. Conclusions : In order to get the knowledge about emergency treatment of traumatic injuries in military men, it is necessary to develop the professional education program for the dental hygiene personnel.

STUDY ON ENTRANCE SKIN DOSE AT PANORAMIC RADIOGRAPHY IN INCHEON, KOREA

  • Choi, Jung-Hyun;Kim, Sung-Chul;Han, Dong Kyoon
    • Journal of Radiation Protection and Research
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    • v.39 no.4
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    • pp.182-186
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    • 2014
  • Recently, the use of panoramic radiography has shown a constant increase, and significant research is underway. However, radiation exposure attracts less attention in dental radiography than in other types of radiography. We used an OSLD for measurement of the entrance skin dose in eyeballs and the thyroid region, both of which are not covered by examinations but are included in radiographical regions and are sensitive to radiation, as well as orally in Incheon and reported the results. The entrance skin dose was 0.0282 mSv on average for the oral region, and 0.0259 mSv on average for the eyeball, and 0.0261mSv on average, for thyroid gland. While there is no proper shielding method for the eyeball, a thyroid protector is not used by most hospitals and most hospitals are equipped with an apron and a thyroid protector separately; thus, it is necessary to use an integration of an apron and a thyroid protector and medical device manufacturers need to develop a method for controlling the length of the slit in the slit-type area of radiation occurrence in order to reduce unnecessary exposure.

Compatible Anchors of Silt Protector in Shallow Sea with Mud Seafloor Material (천해역 점성토 지반에 적합한 오탁방지막 기초 앵커)

  • KWEON GI-CHUL;HONG NAM-SEEG;SONG Mu-HYO;CHOI CHANG-GYU
    • Journal of Ocean Engineering and Technology
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    • v.17 no.3 s.52
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    • pp.7-12
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    • 2003
  • The Navy has tested the holding capacity of many kinds of anchors in order to propose the design chart for the holding capacity of drag-embedment anchors. The design chart is only applicable up to the cable bottom angle 60 when load is raised to the ultimate weight. However, the anchor experiences a significant uplift force when the angle is above 60 in shallow seas. In this paper, the procedure for the estimation of the holding capacity of anchors in mud is proposed. Drag-embedment anchors do not function well when there is a significant uplift component of load in soft seafloor materials, such as mud. Under these loading and seafloor conditions, gravity anchors seems to be more efficient. However, they are too heavy for their holding capacity. Therefore, suction pile (hollow concrete block) is more beneficial to the foundntion of silt protector in shallow sea with mud seafloor materials.

Development of Fire-Diagnosis Concrete using Composite Sensors (복합센서를 이용한 화재자현 콘크리트의 개발)

  • Choi, Young-Wha;Kim, Ie-Sung;Park, Kang-Geun
    • Journal of Korean Association for Spatial Structures
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    • v.10 no.4
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    • pp.85-92
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    • 2010
  • Use of concrete has undoubtedly become widespread in construction and civil engineering. Sensors are used to add functional characteristics to concrete. Self-diagnosis concrete is also being developed. The thermal protector used in the study is a sensor using the linear expansion and cubical expansion of metal. The LED(Light Emitting Diode) is a phototransistor type, and to secure high-sensitivity light, the prices of these sensors are low. Rising temperatures of concrete elements can be predicted from LED of the external virtual beam due to operation of thermal protector sensors of concrete beam caused by fire load on the concrete specimen. In this study, the development of fire-diagnosis concrete using composite sensors are the fundamental study for damage detection using simply measurements.

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Trend of DomeTrend of Domestic Patent and Utility Model Application of Head Protector Technologystic Patent and Utility Model Application of Head Protector Technology (머리 안전·보호구 기술의 국내 특허 및 실용신안 출원 동향)

  • Hyunjung Han;Eunkung Jeon
    • Journal of the Korean Society of Clothing and Textiles
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    • v.46 no.6
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    • pp.1128-1141
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    • 2022
  • Due to increased interest in safety in sports, leisure, industries, and daily life; the demand for products that protect the head is increasing. As a preparatory study for the development of head protection for head injury prevention, this study analyzed patents and utility models related to head protection products such as industrial safety helmets, vehicle helmets, and sports protection gear. For this study, 368 patents and utility models for head protection products searched through WipsOn were selected and analyzed by application year, function, application, protection area, main material, and subject. From the analytic results of this study, the quantitative and qualitative flow and characteristics of developing technology related to head protection products were identified. Through the trend of current technology, it provided data to seek the development direction in the future. The significance of this study is to secure objective data to establish a road map for creating new Intellectual Property for head protection products.