• Title/Summary/Keyword: Bow-tie

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A Study on the Improvement of Safety Management by Port Logistics Industry Using Bow-Tie Analysis (Bow-Tie 분석기법을 이용한 항만물류산업 안전관리 개선방안에 관한 연구)

  • KIM, Do-Yean;SIM, Min-Seop;Lee, Jeong-Min;SHIN, Yong-Ran
    • Journal of Navigation and Port Research
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    • v.46 no.1
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    • pp.57-72
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    • 2022
  • The recent increase in international trade volume and explosive increase in cargo volume due to the non-face-to-face society are leading to an increase in risk exposure and safety accidents in the port logistics industry. Consequently, as the atmosphere and consensus on safety are spreading throughout the society, various safety laws are being enacted by the industry. Nevertheless, according to the industrial accidents status analysis by the Ministry of Employment and Labor, the average annual number of injured persons increased by 11.1% and the number of deaths by 4.0% from 2015 to 2019. This means that special attention should be paid to possible future risks and preventive measures for major causes of accidents should be established. Therefore, in this study, risk assessment was conducted based on 5,028 accident cases that were reported by the Korea Occupational Safety and Health Agency for 5 years, from 2016 to 2020, and major risk factors for each industry were derived, and then bow-tie analysis was conducted to perform the risk assessment; Further, the study aimed to derive the causes and preventive measures from the risk factors.

Design of the Broadband Microstrip Bow-tie Patch Antenna for a GPR (GPR용 광대역 마이크로스트립 보우타이 패치 안테나 설계)

  • 김민준;곽영복
    • Proceedings of the Korea Electromagnetic Engineering Society Conference
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    • 2002.11a
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    • pp.227-231
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    • 2002
  • GPR은 건물의 크랙, 지중 매설물과 같은 정보를 수집하기 위해 좁은 펄스를 사용하므로 넓은 대역의 주파수 특성을 가진다. 본 논문에서는 광대역 특성을 가지는 안테나를 마이크로스트립을 이용하여 보우타이 형태로 설계하였다. 설계 기판으로는 $\varepsilon$$_{r}$=4.0, t=1.6 mm의 FR-4 유전체 기판을 사용하였다. 제작된 안테나는 S$_{11}$<-10 ㏈에서 10.62%의 대역폭을 가지고, 5.778GHz에서 -33.3 ㏈의 S$_{11}$과 1.04의 VSWR 값을 나타내었다.

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Design of Ultrawide Band Monopole Antenna (광대역 모노폴 안테나 설계)

  • 이종필;박성욱
    • Proceedings of the Korea Electromagnetic Engineering Society Conference
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    • 2001.11a
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    • pp.136-139
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    • 2001
  • In this paper, we propese a novel wide band printed monopole antenna called the staircase bow-tie monopole antenna (SBMA). We apply an extraordinarr method for an impedance matching to conventional bow-tie monopoles. So we get the SBMA with a very wide band. Our antenna is smaller than a quarter wavelength in size but provides a 2:1 VSWR bandwidth of about 77.8%. An antenna gain and a radiation pattern are about 1.7dBi and omni-directional at 1.7 GHz, respeotively.

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Upper lip tie wrapping into the hard palate and anterior premaxilla causing alveolar hypoplasia

  • Heo, Woong;Ahn, Hee Chang
    • Archives of Craniofacial Surgery
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    • v.19 no.1
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    • pp.48-50
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    • 2018
  • Bony anomaly caused by lip tie is not many reported yet. There was a case of upper lip tie wrapping into the anterior premaxilla. We represent a case of severe upper lip tie of limited lip motion, upper lips curling inside, and alveolar hypoplasia. Male patient was born on June 3, 2016. He had a deep philtral sulcus, low vermilion border and deep cupid's bow of upper lip due to tension of short, stout and very tight frenulum. His upper lip motion was severely restricted in particular lip eversion. There was anterior alveolar hypoplasia with deep sulcus in anterior maxilla. Resection of frenulum cord with Z-plasty was performed at anterior premaxilla and upper lip sulcus. Frenulum was tightly attached to gingiva through gum and into hard palate. Width of frenulum cord was about 1 cm, and length was about 3 cm. He gained upper lip contour including cupid's bow and normal vermilion border after the surgery. This case is severe upper lip tie showing the premaxillary hypoplasia, abnormal lip motion and contour for child. Although there is mild limitation of feeding with upper lip tie child, early detection and treatment are needed to correct bony growth.

Analysis of Corneal Topography for Korean College Students Based on Computer-Assisted Videokeratography (각막지형도 검사를 이용한 대학생의 각막형태에 대한 연구)

  • Lee, Seok-Ju;Ryu, Guen-Chang;Shin, Cheol-Guen;Seong, Jeong-Sub;Kim, In-Suk
    • Journal of Korean Ophthalmic Optics Society
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    • v.11 no.3
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    • pp.241-247
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    • 2006
  • Purpose : To define the distribution of normal corneal topographic patterns of Korean college students and compare them with previously published western data, Bogan et al's study. Methods : Computerized corneal topography was performed 220eyes normal subjects using CTK-922(Topography, swiss made). Mean age of the subjects was 23.2 yr.(range 19 to 57 yr.). The color-coded videokeratographs were classified by a masked observer according to the Bogan et al's classification such as round, oval, symmetric bow tie, asymmetric bow tie, and irregular. Results: The results revealed 57 eyes(25.9%) had round, 14 (6.4%) oval , 41(18.6%)symmetric bow tie, 78(35.5%) asymmetric bow tie, and 30(13.6%) irregular pattern. Conclusions : Our results of topographic patterns show the tendency of more irregular and less round topographic pattern in Korean college students, as compared to that of western adults.

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Mutual Recognition of National Military Airworthiness Authorities: A Streamlined Assessment Process

  • Purton, Leon;Kourousis, Kyriakos I.;Clothier, Reece;Massey, Kevin
    • International Journal of Aeronautical and Space Sciences
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    • v.15 no.1
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    • pp.54-62
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    • 2014
  • The Air and Space Interoperability Council (ASIC) has adopted the European Defence Agency (EDA) process for inter-regulatory military airworthiness authority recognition. However, there are gaps in the application of this process to nations outside of the European Union. This paper proposes a model that can effectively map diverse technical airworthiness regulatory frameworks. This model, referred to as the Product-Behaviour-Process (PBP) Bow-Tie model, provides the systematic structure needed to represent and compare regulatory frameworks. The PBP Bow-Tie model identifies key points of difference that need to be addressed, during inter-agency recognition between the two regulatory authorities. With the intention to adopt global use of the EDA process, the proposed PBP Bow-Tie model can be used as a basis for the successful recognition of regulatory frameworks outside of the European Union. Iris plots produced from the implementation of this model are presented, and proposed as a suitable means of illustrating the outcome of an assessment, and of supporting the comparisons of results. A comparative analysis of the Australian Defence Force and New Zealand Defence Force airworthiness regulatory frameworks is used as a case study. The case study clearly illustrates the effectiveness of the model in discerning regulatory framework differences; moreover, it has offered an opportunity to explore the limitations of the Iris plot.

Design of S-band Turnstile Antenna Using the Parasitic Monopole (기생 모노폴을 이용한 S-band Turnstile 안테나 설계)

  • Lee, Jung-Su;Oh, Chi-Wook;Seo, Gyu-Jae;Oh, Seung-Han
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.17 no.11 s.114
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    • pp.1082-1088
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    • 2006
  • A turnstile antenna using the parasitic monopole has been developed for STSAT-2 TT&C application. The antenna consists of two radiating elements; a bow-tie dipole and a parasitic monopole. The bow-tie dipole is main radiating element, used a bow-tie structure for bandwidth improvement and size reduction. The parasitic monopole improved beamwidth and axial ratio. The input impedance of the antenna is about 50 ohm without a matching circuit. The proposed antenna has beamwidth of $>140^{\circ}$, axial ratio of < 3 dB and VSWR of < 1.5 in the band of $2.075{\sim}2.282GHz$.

Design of a broadband half bow-tie dipole antenna for digital TV Reception (디지털 TV 수신용 광대역 반 보우타이 다이폴 안테나 설계)

  • Lee, Jong-Ig;Yeo, Junho
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2013.05a
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    • pp.61-62
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    • 2013
  • In this paper, a design method for a compact broadband planar dipole antenna fed by a microstrip (MS) line is studied. The proposed broadband dipole is optimized for terrestrial digital television (DTV) receiving. The dipole is fed by an MS line with 75-ohm characteristic impedance on an FR4 substrate and its size is $90mm{\times}180mm$. The dipole is modified to half bow-tie type for size reduction. A simplified balun is adopted for the impedance matching between the MS line and coplanar strip which feeds the dipole. The optimized dipole antenna for DTV band (470-806 MHz) is fabricated on an FR4 substrate and tested experimentally to verify the results of this study.

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A Miniaturized and Band Rejection Characteristic of Bow-Tie Monopole UWB Antenna (보우-타이 모노폴 UWB 안테나의 소형화 및 대역 저지 특성)

  • Choi, Hyung-Seok;Choi, Kyoung;Hwang, Hee-Yong
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.23 no.3
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    • pp.300-305
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    • 2012
  • In this paper, a miniaturized bow-tie monopole UWB antenna with band rejection characteristic is proposed. To miniaturize the proposed antenna, a perfect magnetic wall(PMW) condition is applied to primitive bow-tie monopole antenna. An uneven ground patch, a tapered feeding structure and a edge-chopped main patch are adapted for impedance matching. A quater-lambda slot resonator is inserted at main patch to prevent interference in UWB band from another band. The proposed antenna is fabricated on Taconic RF60-A substrate with relative permittivity of 6.15. The size of the proposed antenna is $30.0{\times}39.7mm^2$, which is only 45 % of the conventional bow-tie monopole antenna. The proposed antenna covers full UWB band with return losses less than -10 dB and has band stop characteristic in 5 GHz WLAN band. The maximum gains are within -1.0~5.0 dBi, the group delay variations are within 1.0 ns and the radiation patterns show directivity characteristics in x-y plane.

A Design of Bow-tie Patch Antenna for UWB (보우타이 패치 안테나의 초광대역화 설계)

  • Moon, Soo-Deok;Park, Jae-Ill;Choi, Kyoung;Kim, Hyoung-Seok;Hwang, Hee-Yong
    • Proceedings of the KIEE Conference
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    • 2004.07c
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    • pp.2049-2051
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    • 2004
  • Bow-tie 마이크로스트립 패치형태로 초광대역 안테나를 설계 제작하였다. 보다 광대역화된 특성을 얻기 위해 급전구조 변화와 반원형태의 기생페치를 추가하였다. 제작된 안테나는 입력단자 부분의 접지면을 전제하고 VSWR${\leq}$2를 기준으로, 슬롯형태가 아닌 패치형태로도 2.3GHz${\sim}$5.5GHz까지 대역폭비 2.4 : 1의 초광대역 특성을 나타냈다. 또한, 수평 단면 패턴에 대하여 넓은 주범을 가지며, 전 대역에서 안정된 방사패턴을 유지 하였다.

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