• Title/Summary/Keyword: Flow Mobility

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Effectiveness Assessment of Additional Gate Installation at a Railway Station: Case Study at Gwang-Myeong Station (철도역 출입구 추가설치 시 효과 평가: 신안산선 광명역 사례를 중심으로)

  • Lim, Kwangkyun;Kim, Sigon
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.41 no.6
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    • pp.715-725
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    • 2021
  • When constructing railway stations, gates shall be located in appropriate locations for convenient use. However, to reduce construction costs, the number of gates was minimized and the location was not appropriately placed to the direction of many users. This study proposed a method to calculate the benefits of additional gate installations using the improvement of pedestrian traffic flow, occupied area and travel time as economic effects. In particular, a method of estimating the percentage of people using certain gates and the number of people by route within the station was proposed. This method was applied to analyze the effect of additional gates to Gwang-myeong Station on the Shinansan Line, which is to be opened in 2025. The effect has only improved in mobility. The first year of its opening was estimated at 5.91 billion won for mobility and 75.8 billion won for cost, and the B/C was 1.21 for 30 years after its opening. It is expected that this method will be applied to systematic effect analysis when additional gates are installed at unopened railway stations as well as existing railway stations.

Mobility of Nitrate and Phosphate through Small Lysimeter with Three Physico-chemically Different Soils (소형 라이시메터시험을 통한 토양특성에 따른 질산과 인산의 이동성 비교)

  • Han, Kyung-Hwa;Ro, Hee-Myong;Cho, Hyun-Jun;Kim, Lee-Yul;Hwang, Seon-Woong;Cho, Hee-Rae;Song, Kwan-Cheol
    • Korean Journal of Soil Science and Fertilizer
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    • v.41 no.4
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    • pp.260-266
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    • 2008
  • Small lysimeter experiment under rain shelter plastic film house was conducted to investigate the effect of soil characteristics on the leaching and soil solution concentration of nitrate and phosphate. Three soils were obtained from different agricultural sites of Korea: Soil A (mesic family of Typic Dystrudepts), Soil B (mixed, mesic family of Typic Udifluvents), and Soil C (artificially disturbed soils under greenhouse). Organic-C contents were in the order of Soil C ($32.4g\;kg^{-1}$) > Soil B ($15.0g\;kg^{-1}$) > Soil A ($8.1g\;kg^{-1}$). Inorganic-N concentration also differed significantly among soils, decreasing in the order of Soil B > Soil C > Soil A. Degree of P saturation (DPS) of Soil C was 178%, about three and fifteen times of Soil B (38%) and Soil A (6%). Prior to treatment, soils in lysimeters (dia. 300 mm, soil length 450 mm) were tabilized by repeated drying and wetting procedures for two weeks. After urea at $150kg\;N\;ha^{-1}$ and $KH_2PO_4$ at $100kg\;P_2O_5\;ha^{-1}$ were applied on the surface of each soil, total volume of irrigation was 213 mm at seven occasions for 65 days. At 13, 25, 35, 37, and 65 days after treatment, soil solution was sampled using rhizosampler at 10, 20, and 30 cm depth and leachate was sampled by free drain out of lysimeter. The volume of leachate was the highest in Soil C, and followed by the order of Soils A and B, whereas the amount of leached nitrate had a reverse trend, i.e. Soil B > Soil A > Soil C. Soil A and B had a significant increase of the nitrate concentration of soil solution at depth of 10 cm after urea-N treatment, but Soil C did not. High nitrate mobility of Soil B, compared to other soils, is presumably due to relatively high clay content, which could induce high extraction of nitrate of soil matrix by anion exclusion effect and slow rate of water flow. Contrary to Soil B, high organic matter content of Soil C could be responsible for its low mobility of nitrate, inducing preferential flow by water-repellency and rapid immobilization of nitrate by a microbial community. Leached phosphate was detected in Soil C only, and continuously increased with increasing amount of leachate. The phosphate concentration of soil solution in Soil B was much lower than in Soil C, and Soil A was below detection limit ($0.01mg\;L^{-1}$), overall similar to the order of degree of P saturation of soils. Phosphate mobility, therefore, could be largely influenced by degree of P saturation of soils but connect with apparent leaching loss only more than any threshold of P accumulation.

Effects of Nursing Intervention of Mutual Goal Setting on Gastrectomy Patients According to Health Locus of Control (위절제술환자의 건강통제위에 따른 상호목표설정 간호중재의 효과)

  • Jang Eun-Hee
    • Journal of Korean Academy of Fundamentals of Nursing
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    • v.5 no.1
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    • pp.107-124
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    • 1998
  • Based on King's goal attainment theory, this research deals with applying nursing intervention of mutual goal settings to gastrectomy patients. It tests the effects of nursing intervention, according to the patients' health locus of control, suggested as external boundary criteria for the theory by employing a quasi-experimental design which consists of a pretest-posttest non-equivalent control and experimental groups. The subjects of this research were 62 gastrectomy patients hospitalized at Y medical center and the experimental and control groups consisted of 31 subjects. The experimental group received nursing intervention at the mutual goal setting of 5 times from the day before the surgery to the 5th day after the surgery, while the control group received only routine nursing care. Recovery indicators of both groups were measured and compared. Measurement variables included patients' characteristics, health locus of control, forced vital capacity, forced expiratory volume in one second, peak expiratory flow, bowel movement recovery, mobility recovery, level of pain, patients' stress and patients' satisfaction. Data were analyzed using SPSS statistical package and the hypotheses were tested by ANOVA and ANCOVA. Results of the analyses are summarized as follows : 1) Internal health locus of control had higher effects of the nursing intervention of mutual goal setting than external health locus of control on pulmonary ventilatory functions of forced vital capacity, forced expiratory volume in one second, and peak expiratory flow. 2) There was no statistically significant difference in the effects of nursing intervention of mutual goal setting on the bowel movement recovery between the internal and external health locus of control. 3) There was no statistically significant difference in the effects of nursing intervention of mutual goal setting on the mobility recovery between the internal and external health locus of control. 4) There was no statistically significant difference in the effects of nursing intervention of mutual goal setting on the level of pain between the internal and external health locus of control. 5) There was no statistically significant difference in the effects of nursing intervention of mutual goal setting on the level of stress between the internal and external health locus of control. 6) There was a statistically significant difference in the effects of nursing intervention of mutual goal setting on the level of satisfaction with provision of nursing information between the internal and external health locus of control, and there was no statistically significant difference in the effects of nursing intervention of mutual goal setting on the level of satisfaction with outcome of nursing between the internal and external locus of control. On the basis of the research results, the following are recommended : 1) Repeated research on responses to health locus of control is necessary. 2) Not only the effectiveness of nursing intervention in acute recovery periods, but also the long term effects are to be investigated. 3) The development of instruments is needed to accurately measure mutual goal setting regarding postoperative deep breath, coughing, early ambulation, etc. so that the relationship among the postoperative recovery indicators may be explored. 4) It is required that an instrument be developed to measure perception which facilitates goal attainment in the interactive setting between patients and nurses.

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Methods of Regulating Migration Processes in EU Countries

  • Hamova, Oksana;Dergach, Anna;Pikulyk, Oksana;Zolotykh, Irina;Diachenko, Kateryna
    • International Journal of Computer Science & Network Security
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    • v.21 no.3
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    • pp.257-265
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    • 2021
  • Modern methods of regulating migration processes in EU states include a wide variety of adapted, transformed under the sway of globalization tools in order to influence the movement of human capital within the European space. The main purpose of the regulatory policy on migration flows is the redistribution of professionally competent professionals between different spheres of life. Herewith, the determining factor in the effectiveness of such distribution is a rational combination of stimulating and disincentive levers of influence on the movement of citizens of different EU countries and taking into account the motives of such mobility. Modernization of migration management approaches can be a major economic, social, political and cultural progress of European countries. The purpose of the research is to conduct a detailed analysis of existing practices of migration flow management, in particular their stimulation or containment, and to outline key migration trends formed under the influence of multicomponent approaches to migration regulation, transformation of regulatory legislation and changing priorities of modern society. The research methods: statistical-analytical method; ARIS method; method of tabular, graphical and analytical modeling; comparative analysis; systematization, generalization. Results. Current pan-European methods of regulating migration processes are insufficiently adapted to the multinational socialeconomic space; consequently, there are some disparities in the distribution of migrants between EU countries, although the overall dynamics of migration is positive. Fluctuations in the population of European countries during 2000-2019 and trends in the transformation of social-economic space confirm the insufficient level of influence of current methods of regulating migration flows. Along with this, the presence of a characteristic asymmetry in the distribution of migrants requires a greater focus on the modernization of regulatory instruments, in particular, the regulatory mechanism for managing migration processes. As a result of the conducted study, further prospects for the implementation of alternative methods of regulating migration processes in EU states have been outlined; the current and projected limits for increasing the level of observance of migrants' rights at the European level have been clarified through the adoption of appropriate regulatory acts; effective solutions for intensifying the influx of high-quality labor resources from different countries to EU have been identified. The research results can be used to study methods of regulating migration processes in the countries in the global dimension.

Computational Simulation of Coaxial eVTOL Aircraft in Ground Effect (동축 반전 전기동력 수직이착륙기의 지면 효과에 대한 전산해석)

  • Yang, Jin-Yong;Lee, Hyeok-Jin;Myong, Rho-Shin;Lee, Hakjin
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.50 no.9
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    • pp.599-608
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    • 2022
  • Urban air mobility (UAM) equipped with rotor system is subject to ground effect at vertiport during takeoff and landing. The aerodynamic performance of the aircraft in ground effect should be analyzed for the safe operation. In this study, The ground effects on the aerodynamic performance and wake structure of the quadcopter electric vertical takeoff and landing (eVTOL) configuration equipped with coaxial counter-rotating propellers were investigated by using the lattice Boltzmann method (LBM). The influence of the ground effect was observed differently in the upper and lower propellers of the coaxial counter-rotating propeller system. There was no significant change in the aerodynamic performance of the upper propeller even if the propeller height above the ground was changed, whereas the averaged thrust and torque of the lower propeller increased significantly as propeller height decreased. In addition, the amplitude of the thrust fluctuation tended to increase as the propeller height decreased. The propeller wake was not sufficiently propagated downstream and was diffused along the ground due to the outwash flow developed by the ground effect. The impingement of the rotor wakes on the ground and a fountain vortex structure were observed.

Study on Improvement Plans for Installation and Operation of Traffic Safety Facilities according to Differences in Perception Methods and Range of Autonomous Vehicles and Human Vehicles (자율주행차량과 일반차량의 인지 방식과 범위의 차이에 따른 교통안전시설 설치 및 운영 개선방안 연구)

  • Hyeokjun Jang;Eunjeong Ko;Eum Han;Kitae Jang
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.22 no.1
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    • pp.311-326
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    • 2023
  • This paper proposes a plan to improve the installation and operation of traffic safety facilities using a microscopic simulation by confirming the difference in the perception method and range of autonomous vehicles and human vehicles. In this study, the existing 『Traffic Safety Sign Installation·Management Guidelines』 was reviewed, and safety signs among traffic safety facilities were classified according to changes in vehicle behavior. Subsequently, for the classified facilities, the installation location of the traffic sign was changed through simulation experiments, and the optimal location was inferred to suggest an improvement plan. This study confirmed how traffic safety facilities installed based on the visibility of human drivers affect road efficiency and safety in mixed traffic flow with autonomous vehicles and human-controlled vehicles. The optimal location derived through this study is meaningful because it can be used as the basis for revising the guidelines on the installation and management of traffic safety facilities.

Crystal growth of GaN semiconductor films by counter-flow metal-organic chemical vapor deposition (암모니아 역류형태의 반응로를 이용한 GaN 반도체 박막의 성장)

  • 김근주;황영훈
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.9 no.6
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    • pp.574-579
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    • 1999
  • A counter-flow type horizontal reactor of metal organic chemical vapor deposition was designed with the Reynolds and the Rayleigh numbers of Re = 4.5 and Ra = 215.8, respectively. The GaN thin films were grown and characterized by Hall measurement, double crystal X-ray diffraction analysis and photoluminescence measurement. The Si and Mg were also used for doping of GaN films. The dislocation density of $2.6{\times}10^8/\textrm {cm}^2$ was included in GaN films representing the geometrical lattice mismatch between sapphire substrates and GaN films. The Si doped n-GaN films provide the electron carrier density and mobility in the regions of $10^{17}~10^{18}/\textrm{cm}^3$ and 200~400 $\textrm{cm}^2$/V .sec, respectively. Mg doped p-GaN films were post-annealed and activated with the hole carrier density of $8{\times}10^{17}/{\textrm}{cm}^3$.

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Over-education and University Selection Behavior of Local High School Leavers: A Case Study, Chungbuk, Korea (대학교육기회의 확대와 대학진학행동: 충청북도를 사례로)

  • 조영국
    • Journal of the Economic Geographical Society of Korea
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    • v.6 no.1
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    • pp.145-170
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    • 2003
  • Since 1980's, the opportunities of higher education have increased absolutely to the extent worrying of over-education. The over-education means that job-seekers having a bachelor degree flow into job market much more than necessary and the problem of unemployment and under-employment becomes more serious. These changes in the labor market can affect the university selection behaviors of high school graduates. This study aims to reveal the impacts of over-education in Chungbuk, a periphery region, Korea. As expected, many of college graduates flow down into jobs asking school years less than higher education. On the other hand, high school graduates have an tendency of choosing a college, especially a college in center region, other than universities in Chungbuk, to expect more stable and rewarding job in income and upward mobility after the graduation of higher education. As the result of this, a regional university district, which means most of students in the region enter college within region limit, is getting broken into more smaller districts, a kind of local district. It can be thought as a sign that the dominance of regional center is weakening and more cities in the region receive a direct affects from center region, not through regional center.

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Neurobiology and Neurobiomechanics for Neural Mobilization (신경가동성에 대한 신경생물학과 신경생역학적 이해)

  • Kim Jae-Hun;Yuk Goon-Chan;Bae Sung-Soo
    • The Journal of Korean Physical Therapy
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    • v.15 no.2
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    • pp.67-74
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    • 2003
  • Nervous system is clinically important, and involved in most disorders directly or indirectly. It could be injury and be a source of symptoms. Injury of central or peripheral nervous system injury may affect that mechanism and interrupt normal function. An understanding of the concepts of axonal transport is important for physical therapist who treat injury of nerves. Three connective tissue layers are the endoneurium, perineurium, epineurium. Each has its own special structural characteristics and functional properties. The blood supply to the nervous system is well equipped in all dynamic and static postures with intrinsic and extrinsic vasculation. After nerve injury, alternations in the ionic compression or pressures within this environment may interfere with blood flow and, consequently conduction and the flow of axoplasm. The cytoskeleton are not static. On the contrary, elements of the cytoskeleton are dynamically regulated and are very likely in continual motion. It permits neural mobility. There are different axonal transport systems within a single axon, of which two main flows have been identified : First, anterograde transport system, Secondly, retrograde transport system. The nervous system adapts lengthening in two basic ways. The one is that the development of tension or increased pressure within the tissues, increased intradural pressure. The other is movements that are gross movement and movement occurring intraneurally between the connective tissues and the neural tissues. In this article, we emphasize the biologic aspects of nervous system that influenced by therapeutic approaches. Although identified scientific information in basic science is utilized at clinic, we would attain the more therapeutic effects and develop the physical therapy science.

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Travel Time Forecasting in an Interrupted Traffic Flow by adopting Historical Profile and Time-Space Data Fusion (히스토리컬 프로파일 구축과 시.공간 자료합성에 의한 단속류 통행시간 예측)

  • Yeo, Tae-Dong;Han, Gyeong-Su;Bae, Sang-Hun
    • Journal of Korean Society of Transportation
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    • v.27 no.2
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    • pp.133-144
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    • 2009
  • In Korea, the ITS project has been progressed to improve traffic mobility and safety. Further, it is to relieve traffic jam by supply real time travel information for drivers and to promote traffic convenience and safety. It is important that the traffic information is provided accurately. This study was conducted outlier elimination and missing data adjustment to improve accuracy of raw data. A method for raise reliability of travel time prediction information was presented. We developed Historical Profile model and adjustment formula to reflect quality of interrupted flow. We predicted travel time by developed Historical Profile model and adjustment formula and verified by comparison between developed model and existing model such as Neural Network model and Kalman Filter model. The results of comparative analysis clarified that developed model and Karlman Filter model similarity predicted in general situation but developed model was more accurate than other models in incident situation.