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Sudden unexpected cardio-respiratory arrest after venipuncture in children

  • Jeong, Goun;Shin, Son Moon;Kim, Nam Su;Ahn, Young Min
    • Clinical and Experimental Pediatrics
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    • v.61 no.4
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    • pp.108-113
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    • 2018
  • Purpose: This study aimed to investigate the clinical and socioenvironmental characteristics of sudden cardiorespiratory arrest after venipuncture in children. Methods: We conducted a retrospective email-based survey of all members of the Korean Pediatric Society. The questionnaire included items on patient demographics, socioenvironmental circumstances of the venipuncture, type of cardiorespiratory arrest, symptoms and signs, treatment, prognosis, and presumed cause of the arrest. Results: Fourteen patients were identified. Of these, 13 were young children (<2 years old), and 1 was 14 years old. All patients had been previously healthy and had no specific risk factors for sudden cardiorespiratory arrest. Most cases (n=11, 79%) were defined as cardiac or cardiorespiratory arrest, while the remaining cases (n=3, 21%) were defined as respiratory arrest. Aspiration (n=3), acute myocarditis (n=2), and laryngeal chemoreflex (n=1) were presumed as the causes; however, the exact causes were unclear. The overall prognosis was poor (death, n=7; morbidity, n=5; full recovery, n=2). The medical institutions faced severe backlash because of these incidents (out-of-court settlement, n=5; medical lawsuit, n=5; continuous harassment, n=3). Conclusion: Cardiorespiratory arrest after venipuncture is unpredictable and the probable cause of most cases is a vasovagal reaction. Medical personnel must be aware of the risk of unexpected cardiorespiratory arrest during routine intravenous procedures.

The Development of the Solar Tracking System with High Accuracy by using LabVIEW (LabVIEW를 활용한 고정밀도 태양추적장치 개발)

  • Oh, Seung-Jin;Cho, Yil-Sik;Lee, Yoon-Joon;Chun, Won-Gee
    • 한국태양에너지학회:학술대회논문집
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    • 2009.04a
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    • pp.31-36
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    • 2009
  • There have been many solar tracking systems developed for the high accuracy in solar tracking. One of the key components of any motion control system is software. LabVIEW offers an ideal combination of flexibility, ease-of-use and well-integration with other I/O pieces for developing solar tracking system. Real-time solar positions which vary with GPS's data are used simultaneously to control the solar tracker by a chain of operating modes between the open and closed loops. This paper introduces a step by step procedure for the fabrication and performance assessment of a precision solar tracking system. The system developed in this study consists of motion controllers, motor drives, step-motors, feedback devices and application. CRD sensors are applied for the solar tracking system which play a primary role in poor conditions for tracking due to a gear backlash and a strong wind. Mini-dish was used as a concentrator for collecting sun light. The solar position data, in terms of azimuth and elevation, sunrise and sunset times was compared with those of KASI(Korea Astronomy & Space Science Institute). The results presented in this paper demonstrate the accuracy of the present system in solar tracking and utilization.

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Performance Assessment of Linear Motor for High Speed Machining Center (고속 HMC 이송계의 운동 특성 평가)

  • 홍원표;강은구;이석우;최헌종
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2003.06a
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    • pp.158-161
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    • 2003
  • Recently, the evolution in production techniques (e.g. high-speed milling), the complex shapes involved in modem production design, and the ever increasing pressure for higher productivity demand a drastic improvement of the dynamic behavior of the machine tool axes used in production machinery. And also machine tools of multi functional and minimized parts are increasingly required as demand of higher accurate in some fields such as electronic and optical components etc. The accuracy and the productivity of machined parts are natural to depend on the linear system of machine tools. The complex workpiece surfaces encountered in present-day products and generated by CAD systems are to be transformed into tool paths for machine tools. The more complex these tool paths and the higher the speed requirements, the higher the acceleration requirements are needed to the machine tool axes and the motion control system, and the more difficult it is to meet the requirements. The traditional indirect drive design for high speed machine tools, which consists of a rotary motor with a ball-screw transmission to the slide, is limited in speed, acceleration, and accuracy. The direct drive design of machine tool axes. which is based on linear motors and which recently appeared on the market. is a viable candidate to meet the ever increasing demands, because of these advantages such as no backlash, less friction, no mechanical limitations on acceleration and velocity and mechanical simplicity. Therefore performance tests were carried out to machine tool axes based on linear motor. Especially, dynamic characteristics were investigated through circular test.

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A Study on Effect of Various Cooling Methods in Motion of High-Precision Ball Screw (고속 고정밀 볼 스크류 구동에 따른 강제 냉각방식의 효과에 관한 연구)

  • Kim, Su-Sang;Xu, Zhe-Zhu;Kim, Hyun-Koo;Lyu, Sung-Ki
    • Journal of the Korean Society for Precision Engineering
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    • v.30 no.3
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    • pp.254-259
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    • 2013
  • Ball screw system is widely used as a precision mechanical linear actuator that translates rotational motion to linear motion for its high efficiency, great stiffness and long life. Recently, according to the requirements of high accuracy and stiffness, the pre-load on the ball screw which means of remove the backlash in the ball screw is usually used. Because of the preload which means the frictional resistance between the screw and nut, becomes a dominating heat source and it generates thermal deformation of ball screw which is the reason for low accuracy of the positioning decision. There are several methods to solve the problem that includes temperature control, thermal stable design and error compensation. In the past years, researchers focused on the error compensation technique for its ability to correct ball screw error effectively rather than the capabilities of careful machine design and manufacturing. Significant amounts of researches have been done to real-time error compensation. But in this paper, we developed a series of cooling methods to get thermal equilibrium in the ball screw system. So we find the optimum cooling type for improving positioning error which caused by thermal deformation in the ball screw system.

Heritage Soft Power in East Asia's Memory Contests: Promoting and Objecting to Dissonant Heritage in UNESCO

  • Nakano, Ryoko
    • Journal of Contemporary Eastern Asia
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    • v.17 no.1
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    • pp.50-67
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    • 2018
  • Heritage has entered the center stage of public diplomacy in East Asia. Competition to claim and interpret memories of World War II in East Asia has driven campaigns to list heritage items with UNESCO. State and non-state actors aim to use heritage listings to present a particular view of the war and related history to domestic and international audiences. This paper highlights the role of heritage soft power in East Asia's "memory contests" by examining the promotion of dissonant modern heritage in UNESCO's heritage programs. It conceptualizes heritage designation as a soft power resource in East Asia and presents a conceptual framework for understanding the hegemonic competition over the "memory regime" that emerged from the structural change in East Asia's regional order. It then uses this framework to analyze the processes by which state and non-state actors promote and/or object to UNESCO recognition of their sites and documents as heritage of outstanding universal value or world significance. The elements of this process are illustrated with case studies of two very different pieces of heritage, Japan's "Sites of the Meiji Industrial Revolution" and China's "Documents of Nanjing Massacre," which were enshrined as significant world heritage in 2015. While state and non-state actors in East Asia are increasingly recognizing the utility of heritage as a soft power resource for advancing specific historical narratives to an international audience, a backlash movement from civil society groups and governments in other countries prevents a purely unilateral interpretation. As a result, the utility of heritage soft power in this context must be significantly qualified.

The Development of Automatic Grease Lubricator Driven by Gear Mechanism with Controlled Operating Time (주유시간 조절이 가능한 기어 메커니즘 구동방식의 자동그리스주유기 개발)

  • Wang, Duck-Hyun;Lee, Kyu-Young;Lee, Sang-Hoon
    • Journal of the Korean Society for Precision Engineering
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    • v.23 no.2 s.179
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    • pp.199-206
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    • 2006
  • Automatic grease lubricator is equipment that provides adequate amount of fresh grease constantly to the shaft and the bearings of machines. It minimizes the friction heat and reduces the friction loss of machines to the least. This research is to develop automatic grease lubricator by gear driven mechanism with controlled operation time. The ultimate design of this equipment is to lubricate an adequate amount of grease by a simple switch clicking according to the advanced set cycle. The backlash of the gear was minimized to increase the output power. To increase the power of gear mechanism, the binding frequency and the thickness of the coil were changed. To control the rotating cycles of the main shaft according to its set numbers, different resistance and chips were used to design the circuit to controls electrical signals with pulse. The body of the lubricator was analyzed by stress analysis with different constructed angle. The stress analysis for differing loading pressures applied to the exterior body of grease lubricator due to the setup angle, was found that the maximum stress was distributed over the outlet part where the grease lubricator suddenly narrowed contracts. Digital mock-up was analyzed and the rapid prototyping(RP) trial products were tested with PCB circuit and grease. The evaluation of the outlet capacity for RP trial products was conducted, because the friction caused by the outlet on the wall surface was an important factor in the operation of the equipment. Finally, the finishing process was applied to decrease the roughness of the surface to a comparable level and was able to test the performance examination for the product.

The Study on Experimental Measurement Method of Hinge Moment Acting on Control Surface of Air Vehicle (비행체 조종면에 작용하는 힌지 모멘트의 시험적 측정 방법 연구)

  • Park, Jong-Min;Chung, Sang-Joon
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.40 no.2
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    • pp.165-170
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    • 2012
  • This paper contains the test method to obtain aerodynamic hinge moments acting on the control surface of air vehicle wing. During the flight, hinge moments make difference between actual control surface angle and control angle which is measured by sensor of actuator. The hinge moments can be obtained by using this difference. Static ground load test and calibration test were conducted to obtain torsional stiffness of control surface actuation system. This results are used to calculate hinge moments. In addition, the mechanical errors of actuation system such as slip angle of mounting point and backlash could be estimated. Using flight test results, this experimental measurement method of hinge moment acting on control surface is conducted. The results of this method are similar to those of numerical simulation method, and the validity of this method is proved.

Vibration Control of Steel-Frame Structures by a Linear Motor Damper (선형 모터 댐퍼를 이용한 철골 구조물의 진동제어)

  • 문석준;정태영;임채욱;정정교;박진일;김두훈
    • Journal of the Earthquake Engineering Society of Korea
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    • v.7 no.2
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    • pp.49-58
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    • 2003
  • The linear motor has not only no backlash and less friction, resulting in very high accuracy, but also mechanical simplicity, higher reliability, and longer lifetime. In this study, a large-capacity hybrid mass damper using linear motor principle has been developed to suppress vibration of large structures. It is designated linear motor damper in this paper. The LMD has been designed to be able to move the auxiliary damper mass of 155kg up to $\pm$250mm stroke. A series of performance tests for LMD control system with $H_{winfty}$ robust controller have been carried out on the full-scale steel frame structure. Through the performance tests, it is confirmed that vibration response levels are reduced down 10dB for the first and second modes of the test structure.

Development Paradigm of Repression and Desire Embodied by Body and Clothing (몸·복식에서 억압과 욕망의 패러다임 개발)

  • Jeong, Ki-Sung;Kim, Min-Ja
    • Journal of the Korean Society of Costume
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    • v.63 no.6
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    • pp.97-112
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    • 2013
  • In this study, physical, social and psychological repression embodied by the body and clothing are referred to instinctual, power and creative desires, respectively, from the point of biological, social and aesthetic views. Desire refers to a behavior to overcome men's imperfections with individual security, sense of belonging and the pursuit of an ideal, which are obtained by living as a social creature. Repression through the body is sub-categorized depending on whether it is temporary or permanent. Repression expressed through clothing is seen through revealing/concealing, contraction/expansion, and deconstruction/ reconstruction. What enables human beings to embrace changes in fashion without fierce resistance or backlash is the changes of formativeness demonstrated by repression through the body and clothing. The aesthetic values drawn from the exhibition of repression and on the body and clothing are categorized into narcissism, fetishism and aestheticism. While narcissism is an instinctive desire grounded on the originality and confidence of the self that results in refusing repression, fetishism is a desire for power that expedites repression in the pursuit of materialistic value or sexual fantasy. Aestheticism is a desire for creativity that symbolizes the body-and-clothing repression in the pursuit of aesthetic idealism. Repression evokes desire, and the pursuit of desire leads to another repression. The aesthetic values of desire for instinct, power and creativity can be substituted with each other for interpretation according to the attitudes of an initiator, a user and a spectator.

Measurement of Improved Learning Outcomes using Job Assignment Teaching Method (직무배정 수업기법의 학습성과 향상도 측정)

  • Kim, Sang-Kyun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.12 no.12
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    • pp.5633-5638
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    • 2011
  • Kim(2011) showed that the team-based teaching method which is focusing on the individual job assignment solves the backlash effects of peer-evaluation method and suggested that it should be studied if the job assignment teaching method does not worsen the learning outcomes[1]. To analyse the learning outcomes of the job assignment teaching method is the purpose of this paper. This paper evaluates the improvement of the learning outcomes which are resulted from a variance of education style that each member of project team was given his specific task. Firstly, all the students evaluate a learning satisfaction and quality of outcomes by themselves. Secondly, an instructor and some professionals evaluate all the outputs. The results showed that the learning outcomes evaluated by students and instructors are improved significantly. The suggested method in this paper, which focuses on the job assignment of team project, could improve the learning outcomes of team project in engineering education.