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Wearing Acceptability of Chemical Protective Clothing during Fire Training (소방훈련시 화학보호복 착용에 따른 동작만족도 연구)

  • Bang, Changhoon;Kwan, Jungsuk
    • Fire Science and Engineering
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    • v.34 no.3
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    • pp.110-115
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    • 2020
  • The aim of this study was to investigate the wearing acceptability of chemical protective clothing during fires and to provide basic data for the safety of firefighters. The results of the study were as follows: Wearer acceptabilities of chemical protective clothing under static movement (e.g., looking at the ceiling with maximum head bending, wrapping one's arms around oneself, sitting obliquely on the floor, and maintaining a crouching position) were 21.7%-47.8% lower than those of general uniforms. When wearing chemical protective suits, the acceptability under static movement was statistically low (p < .001). Wearer acceptabilities of chemical protective clothing under dynamic movement (e.g., running, lifting a heavy object (20 kg) up to the waist, lifting and moving a heavy object (20 kg) by 1 m, lifting a stretcher and walking forward, and lifting a stretcher and walking backward) were 19.2%-47.8% lower than those of general uniforms. When wearing chemical protective suits, the acceptability under dynamic movement was also statistically low (p < .001).

A Wheeled Inverted Pendulum System with an Automatic Standing Arm (자동기립이 가능한 차륜형 역진자 시스템 개발)

  • Lee, Se-Han
    • Journal of the Korean Institute of Intelligent Systems
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    • v.25 no.6
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    • pp.578-584
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    • 2015
  • In this study a moving platform for a mobile robot that can be traveling with a full automatic standing arm was developed. Conventional mobile robots generally may equip 4 wheels or 3 wheels with a caster wheel or independent driven wheels and have good statistic stability. When a mobile robot travels on a sharply perpendicular and narrow crossroad, it may need a special steering scheme such as going forward and backward repeatedly or it is sometimes physically impossible for the robot to go through the crossroad because of the size limit. The upright running mobile robot changes its posture to the upright posture which has a small planar area and is able to go through the crossroad. The upright control which was manually performed step by step before such as sequences of uprighting (returning), checking, and balancing, is now automated.

The Study on the Lower Limb Surface Changes Caused by the Limb Movements (Part 1) (동작에 따른 하지피부면의 변화에 관한 연구 (제일보) - 탈관절과 슬관절 굴신을 중심으로 -)

  • 박영득
    • Journal of the Korean Home Economics Association
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    • v.20 no.4
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    • pp.1-12
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    • 1982
  • This study was to investigate the changes of shape of the lower limb surface, the rate of the measurement of expansion and contraction and correlation coefficient between variables caused by hip joint and knee joint movements. The results of the investigation are as follows; 1. According to the development figure of shell when the leg was raised $45^{\circ}$forward($M_{2}$), total length of F.L shortened while B.L lengthened. This result is contarary to $M_{3}$raising the leg $15^{\circ}$ backward. In both $M_{2}$, $M_{3}$movements, the rate of expansion and contraction to the course direction was insignificant. When hip joint was bent $15^{\circ}$ with knee joint $120^{\circ}$bent ($M_{4}$) and hip joint was bent $30^{\circ}$ with knee joint $90^{\circ}$ bent($M_{5}$), upper section of back hip expanded while the front hip section contracted slightly. In the Movement of sitting on the chair($M_{6}$), abdomen, front hip section and upper thight section contracted to the wale direction remarkably while the back hip section expanded conspicuously. 2. According to the rate of expansion and contraction of skin (surface) by the somatometry. In $M_{2}$, C.F.L. upper and middle thight girth contracted and B.L, C.L, L.L expanded. This fact is contarary to M3. In M4, M5, C.F.L showed remarkable contraction and C.B.L expanded remarkably. In $M_{6}$, C.B.L contracted most of all the items measured and knee girth, F.L, L.L, C.B.L, hip girth expanded conspicuously. 3. According to the correlation coefficient between variables. In various movements, the correlation among girth items commonly showed a high or middle grade, the correlation among length items also commonly showed a low grade and that girth and length items showed a very low grade commonly. Waist girth, hip grith, F.L, B.L, L.L items showed that there were significant correlation.

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Numerical Analysis of Natural Convection-Radiation Heat Transfer in an Enclosure Containing Absorbing, emitting and Linear Anisotropic Scattering Medium (흡수,방사 및 선형비등방 산란 매질을 포함하는 밀폐공간내의 자연대류- 복사열전달에 대한 수치해석)

  • 차상명;김종열;박희용
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.16 no.5
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    • pp.952-964
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    • 1992
  • The interaction of natural convection and radiation heat transfer in a two dimensional square enclosure containing absorbing, emitting and linear anisotropically scattering gray medium is numerically analyzed. P-1 and P-3 approximation is introduced to calculate radiation heat transfer. The effects of scattering albedo, wall emissivity, scattering anisotropy, and optical thickness on the characteristics of the flow and temperature field and heat transfer are investigated. Temperature and velocity profiles depend a great deal on the scattering albedo, and the importance of this effect increases with decrease in albelo. Planck number is another important parameter in radiation heat transfer. The increase in scattering albedo increases convection heat transfer and decreases radiation heat transfer at hot wall. However, the increase in scattering albedo decreases both convection and radiation heat transfer at cold wall. The increase in optical thickness decreases radiation heat transfer. The scattering anisotropy has important effects on the radiation heat transfer only. The highly forward scattering leads to an increase of radiation heat transfer whereas the highly backward scattering leads to an decrease of radiation heat transfer. The effect of scattering anisotropy decreases when reducing the wall emissivity.

Development of a Cardiac Catheter Remote Control Robot Platform for Radiofrequency Ablation Intervention (고주파 절제술을 위한 심장전극도자 원격 제어 로봇 플랫폼의 개발)

  • Park, Jun-Woo;Song, Seung-Joon;Lee, Jung-Chan;Choi, Hyuk;Lee, Jung-Joo;Choi, Jae-Soon
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.60 no.7
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    • pp.1417-1426
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    • 2011
  • Radiofrequency ablation through cardiac catheterization is one of minimally invasive intervention procedures used in drug resistant arrhythmia treatment. To facilitate more accurate and precise catheter navigation, systems for robotic cardiac catheter navigation have been developed and commercialized. The authors have been developing a novel robotic catheter navigation system. The system is a network-based master-slave configuration 3-DOF (Degree-Of-Freedom) robotic manipulator for operation with conventional cardiac ablation catheter. The catheter manipulation motion is composed of the translation (forward/backward) and the roll movements of the catheter and knob rotation for the catheter tip articulation. The master manipulator comprises an operator handle compartment for the knob and the roll movement input, and a base platform for the translation movement input. The slave manipulator implements a robotic catheter platform in which conventional cardiac catheter is mounted and the 3-DOF motions of the catheter are controlled. The system software that runs on a realtime OS based PC, implements the master-slave motion synchronization control in the robot system. The master-slave motion synchronization performance tested with step, sinusoidal and arbitrarily varying motion commands showed satisfactory results with acceptable level of steady state error. The developed system will be further improved through evaluation of safety and performance in in vitro and in vivo tests.

Charisma: Trimble's Modernized Differential GPS Reference Station and Integrity Monitor Software

  • Remondi, Benjamin W.
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • v.1
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    • pp.221-226
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    • 2006
  • Around 2002, the United States Coast Guard (USCG) identified a need to re-capitalize their Reference Station (RS) and Integrity Monitor (IM) equipment used in the Nationwide Differential Global Position System (NDGPS). Commercially available off-the-shelf differential RS and IM equipment lacked the open architecture required to support long-term goals that include future system improvements such as use of new civil frequencies on L2 and L5 and realization of a higher rate NDGPS beacon data channel intended to support RTK. The first step in preparing for this future NDGPS was to port current RTCM SC-104 compatible RS and IM functionality onto an open architecture PC-based platform. Trimble's product Charisma is a PC-based RS and IM software designed to meet these USCG goals. In fact USCG engineers provided key designs and design insights throughout the development. We cannot overstate the contribution of the USCG engineers. Fundamental requirements for this effort were that it be sufficiently flexible in hardware and software design to support fluid growth and exploitation of new signals and technologies as they become available, yet remain backward compatible with legacy user receivers and existing site hardware and system architecture. These fundamental goals placed an implicit adaptability requirement on the design of the replacement RS and IM. Additionally, project engineers were to remain focused on sustaining the high level of differential GPS service that 1.5 million legacy users have come to depend on. This paper will present new hardware and software (i.e., Trimble's Charisma software) architecture for the next generation NDGPS RS and IM. This innovative approach to engineering on an open architecture PC-based platform allows the system to continue to fulfill legacy NDGPS system requirements and allows the USCG and others to pursue a scalable hardware re-capitalization strategy. We will use the USCG's recapitalization project to explain the essential role of the Charisma software.

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Design and Implementation of an Around View Monitoring System on MOST150 Network (MOST150 네트워크 기반 차량 주변 감시 시스템의 설계 및 구현)

  • Jang, Si-Woong
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.18 no.11
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    • pp.2765-2770
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    • 2014
  • Rear view cameras which help to park or to drive backward has been distributed through after-market, but it is inconvenient because they do not provide views of left, right and front sides. Around view monitoring(AVM) systems which can monitor around vehicle at a glance have been developed and equipped by vehicle vendor but systematic studies on these systems is lack. While the AVM system which equipped on Infiniti cars of Nissan is adequate to monitor around vehicle at a glance, it has disadvantages that additional cabling because of using analog cables is required and image quality is lowered due to EMI/EMC intervention. The around view monitoring system implemented in this paper has advantages that there are no EMI/EMC problems because of using optical network and that cabling is simple because of using plug-and-play ways. Additionally, an advantage of MOST150 network is that camera nodes and display node can be easily installed in the form of plug-and-play.

Centrality Analysis of Industry Sector for National Flagship Industry Selection (국가주력산업 선정을 위한 산업의 중심성 분석)

  • Kim, Sung-Rok;Lee, Jong-Sang
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.1
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    • pp.615-621
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    • 2016
  • The selection of a flagship industry is based on whether the industry's developmental impact is great and whether the industry can be the center of the national economy. Here, a ripple effect may be derived by analyzing the forward and backward linkage effects, but in the case of industries that are the centerpieces of the national economy, each researcher reported different results. Consequently, they could not agree on their flagship industry despite belonging to the same time. This study presents a prestige centrality of network analysis as a way of analyzing an industry, which was the center of the national economy, and performed empirical analysis utilizing the 2013 I-O Table. The analysis showed that the industries classified as those with high centrality include the energy industry, which is essential for economic development, can create a synergy effect with other industries, such as the transportation industry, industries with a high level of export and employment, such as electronics and chemicals, and industries for domestic demand, such as wholesale and retail, food services and accommodation.

Application of Network Coding to IEEE 802.16j Mobile Multi-hop Relay Network for Throughput Enhancement

  • Lee, Kyung-Jun;Sung, Won-Jin;Jang, Ju-Wook
    • Journal of Communications and Networks
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    • v.10 no.4
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    • pp.412-421
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    • 2008
  • We observe simultaneous transmission of relay stations (RSs) allowed in current IEEE 802.16j draft standard for multi-hop relay networks may involve severe interference among the RSs, hence leading to throughput degradation. Allowing only 1/3 of the RSs to simultaneously transmit instead of 1/2 RSs as in the current draft standard reduces the interference but results in reduced throughput. To remedy this problem, we devise schemes to incorporate network coding at link-layer level (decode-and-forward) into the simultaneous transmission of RSs. Data movement is rearranged to maximize coding gain. Formula is derived to dictate exact movement of packets traveling between base station (BS) and mobile stations (MSs) via intermediate RSs. The frame structure in the current IEEE 802.16j draft standard does not allow broadcast needed for network coding. We devise a new frame structure which supports the broadcast. A new R-MAP (pointers to the burst data) is introduced to implement the broadcast. Since our new frame structure is used only for BS to RS or RS to RS communication, our schemes retain backward compatibility with legacy MSs based on IEEE 802.16e standard. Simulation based on simple configuration of RSs shows considerable improvement in terms of system throughput and round trip delay. For a 4-hop relay network with 1 BS and 4 RSs with symmetric traffic in uplink (UL) and downlink (DL), throughput is improved by 49% in DL and by 84% in UL traffic compared with IEEE 802.16j draft standard under the assumption that omni-directional antennae are used in BS and RSs.

Efficient RFID Search Protocols Providing Enhanced User Privacy (강화된 사용자 프라이버시를 보장하는 효율적인 RFID 검색 프로토콜)

  • Lim, Ji-Hwan;Oh, Hee-Kuck;Nyang, Dae-Hun;Lee, Mun-Kyu;Kim, Sang-Jin
    • The KIPS Transactions:PartC
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    • v.16C no.3
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    • pp.347-356
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    • 2009
  • In an RFID search protocol, a reader uses designated query to determine whether a specific tag is in the vicinity of the reader. This fundamental difference makes search protocol more vulnerable to replay attacks than authentication protocols. Due to this, techniques used in existing RFID authentication protocols may not be suitable for RFID search protocols. In this paper, we propose two RFID search protocols, one based on static ID and the other based on dynamic ID, which use counter to prevent replay attacks. Moreover, we propose a security model for RFID search protocols that includes forward/backward traceability, de-synchronization and forgery attack. Based on this model, we analyze security of our protocols and related works.