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Analysis of Medical Records and Development of Chest Pain Care Record in the Emergency Department (의무 기록 분석을 통한 응급실 흉통 간호 기록지 개발)

  • Choi, Gui Yun;Moon, Young Sook;Hong, Eun Seog
    • Korean Journal of Adult Nursing
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    • v.18 no.4
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    • pp.533-542
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    • 2006
  • Purpose: The purposes of this study were to investigate medical records and to develop care records for management of patients with chest pain in the emergency department. Method: Retrospective review of the 42 medical chart of patients presented to the emergency department with chest pain were used. The collected data were analyzed with a frequency of items in the medical records. Results: In a frequency analysis of recorded items for doctors' chest pain assessment during history taking, the history/risk factors was the highest rank. The following ranks were 'commenced with when/timing, extra symptoms, place, nature, stay/radiate, alleviate/aggravate, intensity' in sequence. In a frequency of recorded items in nurse's progress notes according to nursing actions, the 'checking/monitoring' was the highest rank. The following ranks were 'performing, administering/injecting, referring/arranging, testing, preparing/catheterizing, teaching/informing' in sequence. Chest pain care records for the emergency department was designed, based upon data analysis and literature review. Conclusion: The designed records can be a rapid and effective approach tool for assessment and recording of patients with chest pain. Further research is necessary for evaluating the designed chest pain care records.

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Computer-aided approach for modelling of FG cylindrical shell sandwich with ring supports

  • Hussain, Muzamal;Naeem, Muhammad Nawaz;Khan, Muhammad Shabaz;Tounsi, Abdelouahed
    • Computers and Concrete
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    • v.25 no.5
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    • pp.411-425
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    • 2020
  • In this paper, the shell material has been taken as functionally graded material and their material quantity is located by the exponential volume fraction law. Moreover, the impact of ring supports around the shell circumference has been examined for their various positions along the shell axial length. These rings support restraints the radial displacement in the transverse direction. While the axial modal deformation functions have been estimated by characteristic beam functions and nature of materials used for construction of cylindrical shells. The fundamental natural frequency of cylindrical shell of parameter versus ratios of length- and height-to-radius for a wide range has been reported and investigated through the study. In addition, by increasing height-to-radius ratio resulting frequencies also increase and frequencies decrease on ratio of length-to-radius. Though the trends of frequency values of both ratios are converse to each other with three different boundary conditions. Also it is examined the position of ring supports with length-to radius ratio, height-to-radius ratio and varying the exponent of volume fraction. MATLAB software package has been utilized for extracting shell frequency spectra. The obtained results are confirmed by comparing with available literature.

Atomic Force Microscopy and Specular Reflectance Infrared Spectroscopic Studies of the Surface Structure of Polypropylene Treated with Argon and Oxygen Plasmas

  • Seo Eun-Deock
    • Macromolecular Research
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    • v.12 no.6
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    • pp.608-614
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    • 2004
  • Isotactic polypropylene (PP) surfaces were modified with argon and oxygen plasmas using a radio­frequency (RF) glow discharge at 240 mTorr and 40 W. The changes in topography and surface structure were investigated by atomic force microscopy (AFM) in conjunction with specular reflectance of infrared (IR) microspectroscopy. Under our operating conditions, the AFM image analysis revealed that longer plasma treatment resulted in significant ablation on the PP surface, regardless of the kind of plasma employed, but the topography was dependent on the nature of the gases. Specular reflectance IR spectroscopic analysis indicated that the constant removal of surface material was an important ablative aspect when using either plasma, but the nature of the ablative behavior and the resultant aging effects were clearly dependent on the choice of plasma. The use of argon plasma resulted in a negligible aging effect; in contrast, the use of oxygen plasma caused a noticeable aging effect, which was due to reactions of trapped or isolated radicals with oxygen in air, and was partly responsible for the increased surface area caused by ablation. The use of oxygen plasma is believed to be an advantageous approach to modifying polymeric materials with functionalized surfaces, e.g., for surface grafting of unsaturated monomers and incorporating oxygen-containing groups onto PP.

State Transformations for Regenerative Sampling in Simulation Experiments

  • Kim, Yun-Bae
    • IE interfaces
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    • v.11 no.3
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    • pp.89-101
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    • 1998
  • The randomness of the input variables in simulation experiments produce output responses which are also realizations of random variables. The random responses make necessary the use of statistical inferences to adequately describe the stochastic nature of the output. The analysis of the simulation output of non-terminating simulations is frequently complicated by the autocorrelation of the output data and the effect of the initial conditions that produces biased estimates. The regenerative method has been developed to deal with some of the problems created by the random nature of the simulation experiments. It provides a simple solution to some tactical problems and can produce valid statistical results. However, not all processes can he modeled using the regenerative method. Other processes modeled as regenerative may not return to a given demarcating state frequently enough to allow for adequate statistical analysis. This paper shows how the state transformation concept was successfully used in a queueing model and a job shop model. Although the first example can be analyzed using the regenerative method. it has the problem of too few recurrences under certain conditions. The second model has the problem of no recurrences. In both cases, the state transformation increase the frequency of the demarcating state. It was shown that time state transformations are regenerative and produce more cycles than the best typical discrete demarcating state in a given run length.

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A Study on the Near Wake of a Square Cylinder Using Particle Image Velocimetry (III) - Phase Average - (PIV기법을 이용한정사각실린더의 근접후류에 관한 연구 (III) - 위상평균유동장 -)

  • Lee, Man-Bok;Kim, Gyeong-Cheon
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.25 no.11
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    • pp.1527-1534
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    • 2001
  • Phase averaged velocity fields in the near wake region behind a square cylinder have been (successfully) obtained using randomly sampled PIV data sets. The Reynolds number based on the flow velocity and the vertex height was 3,900. To identify the phase information, we examined the magnitude of circulation and the center of peak vorticity. The center of vorticity was estimated from lowpass filtered vorticity contours (LES decomposition) adopting a sub-pixel searching algirithm. Due to the sinusoidal nature of firculation which is closely related to the instantaneous vorticity, the location of peak voticity fits well with a sine curve of the circulation magnitude. Conditionally-averaged velocity fields represent the barman vortex shedding phenomenon very well within 5 degrees phase uncertainty. The oscillating nature of the separated shear layer and the separation bubble at the top surface are clearly observed. With the hot-wire measurements of Strouhal frequency, we found thats the convection velocity changes its magnitude very rapidly from 25 to 75 percent of the free stream velocity along the streamwise direction when the flow passes by the recirculation region.

Dynamic Characterization of Noise and Vibration Transmission Paths in Linear Cyclic Systems (I)-Theory-

  • Kim, Han-Jun;Cho, Young-Man
    • Journal of Mechanical Science and Technology
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    • v.14 no.10
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    • pp.1051-1060
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    • 2000
  • Linear cyclic systems (LCS's) are a class of systems whose dynamic behavior changes cyclically. Such cyclic behavior is ubiquitous in systems with fundamentally repetitive motions (e. g. all rotating machinery). Yet, the knowledge of the noise and vibration transmission paths in LCS's is quite limited due to the time-varying nature of their dynamics. The first part of this two-part paper derives a generic expression that describes how the noise and/or vibration are transmitted between two (or multiple) locations in the LCS's. An analysis via the Fourier series and Fourier transform (FT) plays a major role in deriving this expression that turns out to be transfer function dependent upon the cycle position of the system. The cyclic nature of the LCS' transfer functions is shown to generate a series of amplitude modulated input signals whose carrier frequencies are harmonic multiples of the LCS' fundamental frequency. Applicability of signal processing techniques used in the linear time-invariant systems (LTIS's to the general LCSs is also discussed. Then, a criterion is proposed to determine how well a LCS can be approximated as a LTIS. In Part II, experimental validation of the analyses carried out in Part I is provided.

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Nature of the Wiggle Instability of Galactic Spiral Shocks

  • Kim, Woong-Tae;Kim, Yonghwi;Kim, Jeong-Gyu
    • The Bulletin of The Korean Astronomical Society
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    • v.39 no.1
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    • pp.37.2-37.2
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    • 2014
  • Gas in disk galaxies interacts nonlinearly with a underlying stellar spiral potential to form galactic spiral shocks. Numerical simulations typically show that these shocks are unstable to the wiggle instability, forming non-axisymmetric structures with high vorticity. While previous studies suggested that the wiggle instability may arise from the Kelvin-Helmholtz instability or orbit crowding of gas elements near the shock, its physical nature remains uncertain. It was even argued that the wiggle instability is of numerical origin, caused by the inability of a numerical code to resolve a shock that is inclined to numerical grids. In this work, we perform a normal-mode linear stability analysis of galactic spiral shocks as a boundary-value problem. We find that the wiggle instability originates physically from the potential vorticity generation at a distorted shock front. As the gas follows galaxy rotation, it periodically passes through multiple shocks, successively increasing its potential vorticity. This sets up a normal-mode that grows exponentially, with a growth rate comparable to the orbital angular frequency. We show that the results of our linear stability analysis are in good agreement with the those of local hydrodynamic simulations of the wiggle instability.

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A Perspective of Mobile Communication in future (이동통신의 금후의 전망)

  • 조규심
    • Journal of the Korean Professional Engineers Association
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    • v.27 no.1
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    • pp.5-12
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    • 1994
  • In the high degree information society of the 21st century, along with the social activity becoming much more closer, our life style will also be very much changed. Recognition for obtaining various informations rapidly will be anticipated to enhance and the progress of a mobile communication system is greatly expected. This will enable the system to give and receive ″whenever, wherever, whomever, whatsever information.″ In our country, the car telephone and personal mobile communication services of radio calling etc. are diversified by the telecommunication system reformation and by the introduction of competive principle of the hereafter of 1988. Moreover, in accordance with the tariff, the number of subscrier is rapidly increasing. On the other hand, on the utility side of business, for the realization of a mobile communication which is abundant in functional nature, not only the hitherto voice but also non voice system of data communication is being introduced. The Ministry of Communications of Korea has been expediting the effective utilization of limited frequency band of qusai microwave band etc. as a concrete measures for an ever increasing demand. At the same time, to disseminate and promote a mobile communication most effectively, convenience, economic, and safety nature of the system, and in addition to these, international standardization is considered. For constitution of a new mobile communication, the Ministry has been promoting various policies designed for the digitalization of system, utility extention for home. personal level.

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Effects of tube-support parameters on damping of heat exchanger tubes in liquids (튜브지지대 인자가 열교환기 튜브의 감쇠에 미치는 영향)

  • 김범식
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.12 no.5
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    • pp.1003-1015
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    • 1988
  • Damping information is required to analyse heat exchangers for flow-induced vibration. The most important energy dissipation mechanisms in heat exchanger tubes are related to the dynamic interaction between tube and support. In liquids, squeeze-film damping is dominat. Simple experiments were carried out of a two-span tube with one intermediate support to investigate the effects of tube-support parameters, such as: tube-support thickness, diametral clearance, tube eccentricity, tube span length, location of tube-support, and nature of dynamic interaction between tube and tube-support. The results show that squeeze-film damping is much larger for lateral-type motion than for rocking-type motion at the support. Eccentricity was found to be very important. Diametral clearance, support thickness and frequency are also very relevant. The effects of these parameters on squeeze-film damping are formulated and proposed in a semi-empirical expression.

Unsteady Internal Flow Analysis of a Cathode Air Blower Used for Fuel Cell System (연료전지용 캐소드 공기블로어의 비정상 내부유동장 연구)

  • Jang, Choon-Man;Lee, Jong-Sung
    • New & Renewable Energy
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    • v.8 no.3
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    • pp.6-13
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    • 2012
  • This paper describes unsteady internal flow characteristics of a cathode air blower, used for the 1 kW fuel cell system. The cathode air blower considered in the present study is a diaphragm type blower. To analyze the flow field inside the diaphragm cavity, compressible unsteady numerical simulation is performed. Moving mesh system is applied to the numerical analysis for describing the volume change of the diaphragm cavity in time. Throughout a numerical simulation by modeling the inlet and outlet valves in a diaphragm cavity, unsteady nature of an internal flow is successfully analyzed. Variations of mass flow rate, force and pressure on the lower moving plate of a diaphragm cavity are evaluated in time. The computed mass flow rate at the same pressure and rotating frequency of a motor has a maximum of 5 percent error with the experimental data. It is found that flow pattern at the suction process is more complex compared to that at the discharge process. Unsteady nature of internal flow in the cathode air blower is analyzed in detail.