• Title/Summary/Keyword: driving forces

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History of Korean Nursing Education (1900-2000) (한국간호교육 100년 발달사적 연구(1900-2000))

  • Lee, So-Woo
    • The Journal of Korean Academic Society of Nursing Education
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    • v.6 no.2
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    • pp.303-326
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    • 2000
  • Only one hundred years of history in nursing education in Korea is not enough to develop the subject fully as a science. However, the development of Korean nursing education is a great historical event, because Korean nursing education has been accepted by a male-oriented Korean society and has led to a new paradigm in the new millenium. These results are largely due to the Korean people's high enthusiasm for education, as well as Korean women's diligence. I think these 100 years of history can be divided into five periods: (1) the Sunlight period (1900-1911) (2) the New born period (1912-1945) (3) the Settle-down period (1946-1960) (4) the Marked Growth period (1961-1980) (5) the Jumping Period (1981-2000) These classifications are characterized by changes in the educational system, a changed nursing curriculum, educational goals, educational outcomes, and implications. The characteristics of historical development of Korean nursing education was evaluated in three dimensions: structures, contents, and outcome. The structure of Korean nursing education consists of a 3-year program and a 4-year program. Most nursing leaders in Korea hope that these two programs will converge into one system. Secondly, the contents of nursing education in Korea underwent very active changes, according to historical development. These changes in the nursing curriculum have been developed to provide a professional education and develop nursing education as a modern science. Lastly, as to the results of nursing education in Korea, the education was needed to turn out advanced specialists in nursing. In the new millenium, knowledge and information will be the driving forces behind social development. A nation's level of development and creativity in nursing education is the most potent determinant of the future of Korean nursing. The best way to prepare for future challenges will be to create the backbone of a nursing education system. Hence, well-educated nurses in graduate programs should be turned into advanced specialists in nursing. These groups will upgrade the image of Korean nurses, and will have strong influence to improve patient care and the health situation in Korea.

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Analysis of Convective Boiling Heat Transfer for Refrigerant Mixtures in Annular Horizontal Flow (혼합냉매의 환상 유동 증발열전달 해석)

  • Sin, Ji-Yeong;Kim, Min-Su
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.20 no.2
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    • pp.720-729
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    • 1996
  • An analysis of convective boiling heat transfer for refrigerant mixtures is performed for an annular flow to investigate the degradation of the heat transfer rate. Annular flow is selected in this study because a great portion of the evaporator in the refrigeration and air conditioning system is known to be in the annular flow regime. Mass transfer effect due to composition difference between liquid and vapor is included in this analysis, which is considered to be one of driving forces for the mass transfer at the interface. Due to the concentration gradient at the interface the mass transfer is interfered, so is the evaporative heat transfer at the interface. The mass transfer resistance makes the interface temperature slightly higher and, as a result, the heat transfer coefficients decrease compared with those without mass transfer effects. The degradatioin of the heat transfer rate reaches its maximum at a certain composition. The composition difference between vapor core and vapor at the interface has a direct effect on the temperature difference between the vapor core and the interface and the degradation of the heat transfer rate. Correction factor $C_{F}$ for the mixture effects is added to the correlation for pure substances and the flow boiling heat transfer coefficients can be calculated using the modified equation.n.

Fabrication of an Alternating Multilayer Film of Poly(ethylene-alt-maleic anhydride) and Poly(4-vinyl pyridine) by Layer-by-Layer Self-Assembly Method (Layer-by-Layer 자기조립법에 의한 Poly(ethyiene-alt-maleic anhydride)i Poly(4-vinyl pyrtdine) 다층막 제조)

  • Lee Joon Youl;Hong Sook-Young
    • Polymer(Korea)
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    • v.29 no.4
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    • pp.392-398
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    • 2005
  • Self-assembled multilayer thin films of poly(ethylene-alt-maleic anhydride) (PEMAh) and poly(4-vinyl pyridine) (P4VP) were fabricated by layer-by-layer (LbL) sequential adsorption. Fourier transform infrared (FT-IR) spectroscopic analysis of the self-assembled PEMAh/P4VP multilayer films confirms that the driving forces for the multilayer buildup are the intermolecular hydrogen bonding and electrostatic interactions. The linear increase of absorption peak of P4VP at 256 nm with increasing number of PEMAh/P4VP bilayers indicates that the multilayer buildup is an uniform assembling process. We also investigate the effects of polyelectrolyte concenhation variation of the dipping solution and pH variation of the PEMAh solution on the multilayer film formation. Thickness. adsorbed polyelectrolyte mass and surface roughness of the multilayer films were measured by UV-visible spectroscopy, quartz crystal microbalance (QCM), and atomic force microscopy (AFM), respectively.

Analysis of Genes with Alternatively Spliced Transcripts in the Leaf, Root, Panicle and Seed of Rice Using a Long Oligomer Microarray and RNA-Seq

  • Chae, Songhwa;Kim, Joung Sug;Jun, Kyong Mi;Lee, Sang-Bok;Kim, Myung Soon;Nahm, Baek Hie;Kim, Yeon-Ki
    • Molecules and Cells
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    • v.40 no.10
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    • pp.714-730
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    • 2017
  • Pre-mRNA splicing further increases protein diversity acquired through evolution. The underlying driving forces for this phenomenon are unknown, especially in terms of gene expression. A rice alternatively spliced transcript detection microarray (ASDM) and RNA sequencing (RNA-Seq) were applied to differentiate the transcriptome of 4 representative organs of Oryza sativa L. cv. Ilmi: leaves, roots, 1-cm-stage panicles and young seeds at 21 days after pollination. Comparison of data obtained by microarray and RNA-Seq showed a bell-shaped distribution and a co-lineation for highly expressed genes. Transcripts were classified according to the degree of organ enrichment using a coefficient value (CV, the ratio of the standard deviation to the mean values): highly variable (CVI), variable (CVII), and constitutive (CVIII) groups. A higher index of the portion of loci with alternatively spliced transcripts in a group (IAST) value was observed for the constitutive group. Genes of the highly variable group showed the characteristics of the examined organs, and alternatively spliced transcripts tended to exhibit the same organ specificity or less organ preferences, with avoidance of 'organ distinctness'. In addition, within a locus, a tendency of higher expression was found for transcripts with a longer coding sequence (CDS), and a spliced intron was the most commonly found type of alternative splicing for an extended CDS. Thus, pre-mRNA splicing might have evolved to retain maximum functionality in terms of organ preference and multiplicity.

A Study on the Behavior of the Plane Stress Fracture Toughness - About the Compact Tension Specimen- (平面應力 破壞靭性値 擧動에 관한 硏究)

  • 송삼홍;고성위
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.10 no.6
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    • pp.937-946
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    • 1986
  • In this paper, the plane stress fracture toughness of low carbon steel with 3mm thickness is investigated for various specimen widths and crack ratios using the J integral. The experiments is carried out for the compact tension(CT) specimen on an Instron machine. For materials that may be approximated by the Ramberg and Osgood stress strain law, the relevant crack parameter like the J integral and load line displacement are approximately normalized. Crack driving forces in terms of J integral is computed using the above estimation scheme. Abtained results are summarized as follows. (1) The plane stress fracture toughness, J$_{c}$, is almost constant in the range 50-70mm of width. Hence J$_{c}$ can be obtained by using smaller specimen than ASTM standard. (2) Yoon's and Simpson's formular which considers crack growth in obtaining J integral show more consevative J than Rice's and Merkle's (3) J$_{c}$ is almost constant in the range 0.499-0.701 crack ratios tested. J$_{c}$ obtained by using Kumar's formular is 28.14kgf/mm for base metal specimen and 32.51kgf/mm for annealed. (4) Comparison of the prediction with actual experimental measurements by Yoon's formular show good agreement for several different-size specimens.

A Study on the Vibration Analysis of a Deckhouse of Fishing Vessel (어선의 갑판실의 진동 해석법에 관한 연구)

  • 배동명
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.27 no.3
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    • pp.193-210
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    • 1991
  • For the deckhouse or superstructure, attention is directed to the reduction of vibration from a human susceptibility point of view. The two basic requirements for obtaining a low vibration level in the accommodation are to ensure that excitation forces from propeller and/or main engine are small and to avoid resonance excitation of the hull and superstructure. In recent years increased attention has been directed towards the problems of vibration and noise in deckhouse, which have caused major problems with regard to the environmental quality in the living quarters for crews. Accordingly, in this paper, the characteristic of the vibration of deckhouse of fishing boat, of which the length/height ratio is also relatively high, are studied systematically with regard to the shape and modelling of deckhouse based on finite element method of 1-dimensional, 2-dimensional and 3-dimensional model. This study is divided into 4-part. 1st part is the global deckhouse vibration, 2nd part is the local deckhouse vibration, 3rd part consists of the estimation for stiffness of foundational support and 4th part is the application to TUNA LONG LINER of 416 ton class. For the global vibration analysis, the severity of the vibration depends on the longitudinal shear and bending stiffness of the deckhouse, on the vertical deckhouse support(fore, aft and sides). However, even if the design is technically sound, vibration problems may arise due to vertical or longitudinal hull girder or afterbody resonances. Author applied the method of this study to the analysis of, deep-sea fishing vessel of G.T. 416 ton class with relatively low height and long deckhouse, and investigated the vibrational characteristic of the fishing vessel with earlier structural feature. According to this investigation, the vibration, response of above vessel was confirmed of which main hull and deckhouse behave as one body. It is at the bottom of vibrational trouble which a accommodation part of the fishing vessel is raised, that is the local vibration for side wall, fore-aft wall and deck plate of deckhouse rather than thief fect of fore-aft vibration of deckhouse for above fishing vessel. and the resonance of main hull, deckhouse and driving system such as the main engine, propeller in exciting source is mainly brought up as the trouble.

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Research Trends for Performance, Safety, and Comfort Evaluation of Agricultural Tractors: A Review

  • Kabir, Md. Shaha Nur;Ryu, Myong-Jin;Chung, Sun-Ok;Kim, Yong-Joo;Choi, Chang-Hyun;Hong, Soon-Jung;Sung, Je-Hoon
    • Journal of Biosystems Engineering
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    • v.39 no.1
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    • pp.21-33
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    • 2014
  • Background: Significant technological development and changes happened in the tractor industries. Contrariwise, the test procedures of the major standard development organizations (SDO's) remained unchanged or with a little modification over the years, demanding new tractor test standards or improvement of existing ones for tractor performance, safety, and comfort. Purpose: This study focuses on reviewing the research trends regarding performance, safety and comfort evaluation of agricultural tractors. Based on this review, few recommendations were proposed to revise or improve the current test standards. Review: Tractor power take-off power test using the DC electric dynamometer reduced human error in the testing process and increased the accuracy of the test results. GPS signals were used to determine acceleration and converted into torque. High capacity double extended octagonal ring dynamometer has been designed to measure drawbar forces. Numerical optimization methodology has been used to design three-point hitch. Numerous technologies, driving strategies, and transmission characteristics are being considered for reducing emissions of gaseous and particulate pollutants. Engine emission control technology standards need to be revised to meet the exhaust regulations for agricultural tractors. Finite Element Analysis (FEA) program has been used to design Roll-Over Protective Structures (ROPS). Program and methodology has been presented for testing tractor brake systems. Whole-body vibration emission levels have been found to be very dependent upon the nature of field operation performed, and the test track techniques required development/adaptation to improve their suitability during standardized assessment. Emphasizes should be given to improve visibility and thermal environment inside the cab for tractor operator. Tractors need to be evaluated under electromagnetic compatibility test conditions due to large growing of electronic devices. Research trends reviewed in this paper can be considered for possible revision or improvement of tractor performance, safety, and comfort test standards.

Overcoming Experiences of Family Members Caring for Elderly Patients with Dementia at Home (재가 치매 노인환자를 돌보는 가족원의 극복 경험)

  • Sung, Mi Ra;Yi, Myungsun;Lee, Dong Young;Jang, Hye Young
    • Journal of Korean Academy of Nursing
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    • v.43 no.3
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    • pp.389-398
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    • 2013
  • Purpose: The purpose of the study was to understand and describe the overcoming experiences of family members caring for elderly patients with dementia at home. Methods: Data came from autobiographies on the overcoming experiences of caregiving from 31 participants, who had submitted the autobiographies to a public contest held by the Seoul Metropolitan Center for Dementia in 2012. Data were analyzed using qualitative content analysis. Results: Four overcoming stages emerged from the analysis: confronting stage; challenging stage; integrating stage; and transcendental stage, representing transformation of experiences from frustration and suffering to happiness and new hope in life. The confronting stage illustrates severe negative feelings and exhaustion occurring after the diagnosis of dementia. The challenging stage signifies major driving forces in taking good care of their patients. It includes tender loving memories about the patients as well as family and social supports. The integrating stage shows genuine empathy for the patients' situation and the happiness of 'here and now', while the transcendental stage represents new hope in the future. Conclusion: Health professionals need to support caregivers to find true meaning of caring and happiness in everyday life, while providing specific information on dementia care and relieving various negative feelings.

Embedded Inductors in MCM-D for RF Appliction (RF용 MCM-D 기판 내장형 인덕터)

  • 주철원;박성수;백규하;이희태;김성진;송민규
    • Journal of the Microelectronics and Packaging Society
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    • v.7 no.3
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    • pp.31-36
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    • 2000
  • We developed embedded inductors in MCM-D substrate for RF applications. The increasing demand for high density packaging was the driving forces to the development of MCM-D technology. Most of these development efforts have been focused on high performance digital circuits. However, recently there is a great need fur mixed mode circuits with a combination of digital, analog and microwave devices. Mixed mode modules often have a large number of passive components that are connected to a small number of active devices. Integration of passive components into the high density MCM substrate becomes desirable to further reduce cost, size, and weight of electronic systems while improving their performance and reliability. The proposed MCM-D substrate was based on Cu/photosensitive BCB multilayer and Ti/Cu is used to form the interconnect layer. Seed metal was formed with 1000 $\AA$ Ti/3000 $\AA$ Cu by sputtering method and main metal was formed with 3 $\mu\textrm{m}$ Cu by electrical plating method. The multi-turn sprial inductors were designed in coplanar fashion. This paper describe the manufacturing process of integrated inductors in MCM-D substrate and the results of electrical performance test.

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Coil Gun Electromagnetic Launcher (EML) System with Multi-stage Electromagnetic Coils

  • Lee, Su-Jeong;Kim, Ji-Hun;Song, Bong Sob;Kim, Jin Ho
    • Journal of Magnetics
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    • v.18 no.4
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    • pp.481-486
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    • 2013
  • An electromagnetic launcher (EML) system accelerates and launches a projectile by converting electric energy into kinetic energy. There are two types of EML systems under development: the rail gun and the coil gun. A railgun comprises a pair of parallel conducting rails, along which a sliding armature is accelerated by the electromagnetic effects of a current that flows down one rail, into the armature and then back along the other rail, but the high mechanical friction between the projectile and the rail can damage the projectile. A coil gun launches the projectile by the attractive magnetic force of the electromagnetic coil. A higher projectile muzzle velocity needs multiple stages of electromagnetic coils, which makes the coil gun EML system longer. As a result, the installation cost of a coil gun EML system is very high due to the large installation site needed for the EML. We present a coil gun EML system that has a new structure and arrangement for multiple electromagnetic coils to reduce the length of the system. A mathematical model of the proposed coil gun EML system is developed in order to calculate the magnetic field and forces, and to simulate the muzzle velocity of a projectile by driving and switching the electric current into multiple stages of electromagnetic coils. Using the proposed design, the length of the coil gun EML system is shortened by 31% compared with a conventional coil gun system while satisfying a target projectile muzzle velocity of over 100 m/s.