• Title/Summary/Keyword: Impulsive

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Photodissociation Dynamics of Allyl Alcohol in UV: The Exit Channel Barrier for OH Production

  • Lee, Ji-Hye;Kang, Tae-Yeon;Kwon, Chan-Ho;Hwang, Hyon-Seok;Kim, Hong-Lae
    • Bulletin of the Korean Chemical Society
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    • v.32 no.2
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    • pp.510-514
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    • 2011
  • Photodissociation dynamics of allyl alcohol ($H_2C$=CH-$CH_2OH$) has been investigated at 205 - 213 nm along the UV absorption band by measuring rotationally-resolved laser-induced fluorescence spectra of OH radicals. Observed energy partitioning of the available energy among products at all photon energies investigated was similar and the barrier energy for OH production is about 574.7 kJ/mol from the OH yield measurements. The potential energy surfaces for the $S_0$, $T_1$, and $S_1$ excited states along the dissociation coordinate were obtained by ab initio quantum chemical calculations. The observed energy partitioning was successfully modeled by the "barrier-impulsive model" with the reverse barrier and the geometry obtained by the calculated potential energy surfaces. The dissociation takes place on the $T_1$ excited state potential energy surface with an energy barrier in the exit channel and a large portion of the photon energy is distributed in the internal degrees of freedom of the polyatomic products.

6DOF Simulation and Determination of Hydrodynamic Derivatives of Underwater Tow-Fish Using CFD (CFD를 이용한 수중 예인체의 유체력 미계수 결정과 6자유도 운동해석)

  • Go, Gwangsoo;Lee, Euntaek;Ahn, Hyung Taek;Kim, Seongil;Chun, Seung Yong;Kim, Jung Suk;Lee, Byeong Hee
    • Journal of the Society of Naval Architects of Korea
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    • v.53 no.4
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    • pp.315-328
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    • 2016
  • Techniques for determinating hydrodynamic derivatives of underwater tow-fish using CFD(Computational Fluid Dynamics) are described in this paper. Main components of hydrodynamic derivatives are added mass, linear damping and non-linear damping coefficients. In this study, linear and non-linear damping coefficients for translational velocities are settled by CFD analysis. In order to analyze the underwater tow-fish, UlsanFOAM based on open-source CFD code, namely OpenFOAM, is employed. By simulating pitch and yaw angle variation of underwater tow-fish, 6DOF(Degree-of-Freedom) forces and moments are estimated at each attitudes. In order to determinate the hydrodynamic derivatives, curves(forces and moments vs attitude) for CFD results are fitted by least square methods. To demonstrate the applicability of the current approach, two different problems(impulsive side towing and straight towing) are simulated and all results are validated.

A Study on Clothing Buying Motive and Clothing Buying Behavior (의복구매동기와 의복구매행동에 대한 연구-여대생을 중심으로)

  • Park, Hye-Sun;Kwon, Chung-Mun;Kim, Chun-Yo;Lee, Han-Goo;Chol, Hun-soo
    • The Journal of Natural Sciences
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    • v.9 no.1
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    • pp.131-143
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    • 1997
  • The authors studied clothing buying motive and clothing buying behavior. The date were obtained from 352 women college students living in Seoul and Taejon. As the result of factor analysis. four buying motive factors were found: fashion and individuality, economy, status, advertising and impulsive buying. Three buying behaviors(information using, clothing selection standard, and shop selection standard) were factor analyzed. Three factors were founded in information using: human, electric wave communication, advertising and observation factors. Four factors were found in clothing selection standard: utility, design, marketing, fashion and status. Two factors were found in shop selection standard: merchandise and service. Clothing buying motive and clothing buying behavior were related, and they were different according to the levels of spending money and major in college.

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Post-stroke fatigue, depression, emotional incontinence, and anger-proneness (뇌졸중 후 후유증: 피로, 우울, 감정조절 장애, 분노 조절 장애를 중심으로)

  • ChoiKwon, Smi
    • Perspectives in Nursing Science
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    • v.2 no.1
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    • pp.76-91
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    • 2005
  • Stroke patients often develop post stroke sequelae when they survive. Post stroke fatigue and emotional disturbances including depression are common along with motor dysfunction. However, medical personnel have paid relatively little attention to emotional changes and the presence of fatigue following strokes. Post-stroke fatigue was common, occurring in 57% of the patients in our series. The post-stroke fatigue appears to be related to the pre-stroke fatigue, physical disability and post stroke depression (PSD) although the relation to the lesion location remains elusive. The prevalence of post-stroke emotional disturbance has been reported to range from 12% to 64%. The wide variation in the frequency of post stroke depression may be related to methodological heterogeneity in items such as the criteria for depression, the timing of assessment, and the study population. Emotional incontinence, which is characterized by inappropriate or excessive laughing or crying is also common. The incidence of and factor related to this post-stroke emotional incontinence (PSEI) also remains unclear. We reported that out-patients with single, unilateral stroke, 18% had PSD and 34% had PSEI. Although both PSD and PSEI were related to motor dysfunction and location (anterior vs. posterior cortex) of the lesion, the latter was a stronger determinant for PSD. PSEI was more closely associated with subcortical strokes than was PSD. Another manifestation of post stroke patients is the occurrence of post stroke anger proneness (PSAP). They may become easily irritated, impulsive, less generous, and prone to be angry or aggressive at others. We also have reported the PSAP which seems to be closely associated with the presence of PSEI. The lesion distribution appears to be also similar. Both PSEI and PSAP respond well to serotonin reuptake inhibitors suggesting that these symptomsmay be possibly related to the alteration of serotonin after brain injury. Likewise, PSAP also produces a great deal of frustration and embarrassment among patients and caregivers. In summary, emotional disturbances such as depression, emotional incontinence, anger-proneness and fatigue are fairly common but under-recognized sequelae of stroke. These emotional disturbances decrease the quality of life of the patients and caregivers, and may adversely affect the overall prognosis. Therefore, these problems must be appropriately recognized and alleviated. Finding strategies to relieve the symptoms is imperative by understanding the causative factors in individual patient.

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Analysis of Aerodynamic Characteristics for determination of tunnel cross section in Honam high speed railway (호남고속철도 터널 단면선정을 위한 공기역학적 특성 분석)

  • Kim, Seon-Hong;Moon, Yeon-Oh;Seok, Jin-Ho;Jo, Hyeong-Jae;Yoo, Ho-Sik;Choi, Jeong-Hwan;Rim, Hyoung-Gyu
    • Proceedings of the KSR Conference
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    • 2007.11a
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    • pp.313-336
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    • 2007
  • Unlike a conventional railway system, a high-speed rail system experiences various aerodynamic problems in tunnel sections. Trains running at a high speed in a small tunnel, when compared with the open field, face significant air pressure, resulting in reduced operating stability and fast change in pressure inside the tunnel. These phenomena further cause some unexpected problems such as the passengers onboard feeling an aural discomfort and an impulsive noise at the tunnel exit. To solve these problems, this paper introduces analysis of aerodynamic characteristics for determination of tunnel cross section. The optimum cross-section that satisfies the criteria of aural discomfort was reviewed through lots of numerical simulation analysis. Also, the pressure inside the passenger car of a train operating on Kyungbu HSR line was measured, and the pressure inside the tunnel and the micro-pressure waves at tunnel exit were measured at Hwashin 5 Tunnel. At the same time, a test of train operation model was performed and then the measurement results and test results were compared to verify that various parameters used as input conditions for the numerical simulations were appropriate.

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Temperament and Character Traits of Adolescents by Ego Resilience and Ego Control Level (자아탄력-자아통제 수준에 따른 청소년의 기질 및 성격 특성)

  • Jun, Young-Soon;Kim, Tae-Ho;Hwang, Soon-Taeg;Kwon, Eun-Jeong;Lim, Mok-Ok
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • v.23 no.1
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    • pp.14-22
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    • 2012
  • Objectives : The purpose of present study is to identify the differences between temperament and character traits among adolescents classified by ego resilience and ego control level. Methods : A Junior Temperament and Character Inventory (TCI) was performed on participants, and a California Child Q-Test (CCQ) was tested for by the parents of the adolescent participants. Results : The result of the factor analysis and discriminant analysis show that the participants are classified into three different groups based on CCQ score and item response patterns. The three groups are named the ego resilience group, the undercontrolled group, and the overcontrolled group. The ego resilience group indicates that they have a high level of interest and curiosity but yet they are not easily tempered. Moreover, they behave proactively with a reasonable level of responsibility in order to improve themselves. In contrast, among the undercontrolled group, it is observed that, although the group shows even higher level of interest, curiosity and honesty, they are careless, more impulsive, and have a lack of delayed gratification and shame. Conclusions : The overcontrolled group shows that they are the most cautious and reflective group among the three but also show emotional instability such as strong criticism and passive-aggressiveness. In this study, implications and limitations are discussed.

Evaluation to Collision Safety Performance of Stacking Angle Different CFRP/Al Circular Member (적층각이 다른 CFRP/Al 혼성 원형부재의 충돌안전성능 평가)

  • Yang, Yong Jun;Kim, Young Nam;Cha, Cheon Seok;Jung, Jong An;Yang, In Young
    • Journal of the Korean Society of Safety
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    • v.30 no.6
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    • pp.1-6
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    • 2015
  • The actual condition is that environmental pollution due to the development of various industries has recently become a serious issue. An interest in improving the gas mileage is rising due to an increase in the number of vehicles in the era of high oil price in particular. In order to solve this problem, priority should be given to light-weight design of car body, However, at present, a design method enabling the conventional steel plate to be replaced is direly needed in order to guarantee passengers' safety according to excessive light-weight design of car body. In this study, in order to apply a design method that could realize fuel savings and environmental pollution prevention through an improvement in gas mileage together with meeting the safety requirements for vehicles, it was supposed that CFRP/Al composites member would be used as primary structural member. And to this end, it was intended to obtain optimum design data by experimentally implementing external impulsive load applied to the car body. According to results of impact test of CFRP/Al composites member, a collapsed shape of folding, crack, and bending occurred. So, it was possible to find that energy was observed. And in case of specimen having an angle of $90^{\circ}$ in the outermost layer and stack sequence of $[90^{\circ}{_2}/0^{\circ}2]s$, its collapsed length was shown to be short. Therefore, it was possible to find that the absorbed energy was shown to be higher by 20% or above at the maximum.

A NUMERICAL SIMULATION METHOD FOR FREE SURFACE FLOWS NEAR MOVING BODIES IN A FIXED RECTANGULAR GRID SYSTEM (고정된 직사각형 격자계에서 움직이는 물체주위 자유수면유동 계산을 위한 수치기법의 개발)

  • Jeong, K.L.;Lee, Y.G.;Ha, Y.J.
    • 한국전산유체공학회:학술대회논문집
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    • 2011.05a
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    • pp.395-406
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    • 2011
  • In this research a numerical simulation method is developed for moving body in free surface flows using fixed staggered rectangular grid system. The non-linear free surface near the body is defined by marker-density method. The body boundary is defined by line segment connecting the points where the body surface and grid line meet. Continuity equation and Navier-Stokes equations are used as governing equations and the equations are coupled with two-step projection method. The velocities and pressures of body boundary and free surface cells are calculated with simultaneous iterative method. To treat a body movement in a fixed grid system, the volume displaced by moving body is added to the divergence of the body boundary cell. For the verification of the present numerical method. vortex shedding period of advancing cylinder is calculated and the period is compared with existing experiment results. Moreover, added mass and damping coefficients of a vertically excited box are calculated and the computed results are compared with published experiment results. Impulsive pressure and water level variation due to sloshing phenomenon are simulated and the results are compared with published experiment results. Varying the plunger shape, the waves generated by plunging type wave maker are compared with the 2nd order Stokes wave theory The plunger shape generating the wave that shows the best agreement with the theory is represented.

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A Case Study on Living Lifestyle Shop Brands focusing on Store Experiential Factors and an Empirical Study on Store Usage Behavior, Product Purchase Motives, Store Attitudes of Living Lifestyle Shop Consumers (리빙 라이프 스타일 숍 브랜드의 매장 체험요소 사례분석과 소비자들의 매장이용행태, 제품구매동기, 매장태도에 대한 실증적 연구)

  • Seo, Gowoomi;Oh, Kyung Wha
    • Fashion & Textile Research Journal
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    • v.19 no.4
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    • pp.448-467
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    • 2017
  • Attention to living lifestyle shops covering with the wide product range including household items, interior decoration, and bedding have recently increased since consumers have been improving their standard of living and income levels and they are getting more interested in up-to-date trends of global living lifestyles. The purpose of this study is first, to analyze the market situation of living lifestyle shops using the case study method and second, to investigate consumer's store usage behavior, product purchase motives, and attitudes to the living lifestyle shops using the empirical study method. For an empirical study, the survey was conducted with 20s to 50s female respondents who have visited living lifestyle shops and a total of 227 responses were analyzed using SPSS 18.0. The results of this study were as follows. The most frequently visit store was MUJI and most of respondents tended to visit the store once a month and their interest and purchase items were household items. Only impulsive purchase motives among other motives of living lifestyle shops, such as others-oriented, situational, and reasonable motives, significantly had a positive effect on store attitudes toward living lifestyle shops. There were differences in purchasing items at living lifestyle shops depending on marriage status and occupation. Purchase motives of living lifestyle products were statistically influenced by demographic factors such as age, marriage status and income level, however store attitudes were not. The managerial implications for living lifestyle shops are discussed limitations and areas for future research as well.

The Experimental Study about Kinetic Change of Water Surface in the Chambers for Wave Energy Converter (파력발전용 수조실의 수면 운동 변화에 대한 실험적 연구)

  • Hadano, Kesayoshi;Moon, Byung-Young;Lee, Seong-Beom;Kim, Kwang-Jung
    • The KSFM Journal of Fluid Machinery
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    • v.17 no.2
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    • pp.41-47
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    • 2014
  • Experimental results are given for the vertical motion of water in the water chambers for wave energy converter aligned along the wave propagation direction in order to avoid the impulsive wave forces. This paper mainly focuses on the property of the amplitude of the vertical motion of the water surface in the chambers. The amplification has been investigated by dimensionless parameters of wave period to resonance period ratio of the U-shaped oscillation, $T/T_r$, chamber size to wave length ratio, l/L, water depth to wave length ratio, h/L, amplitude of up-down motion of water particles to draft of the front wall ratio, ${\zeta}/D$. It has been shown that l/L should be less than 0.1 and as $T/T_r$ approaches unity the up-down of the water in the chambers is amplified. Also, the structure of the walls which form th water chambers has been examined roughly. It is deduced that the chambers set on both sides of the hull of a single-point moored floating vessel is preferable to those set along a fixed structure such as breakwaters.