• Title/Summary/Keyword: Water transport

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Probabilistic and spectral modelling of dynamic wind effects of quayside container cranes

  • Su, Ning;Peng, Shitao;Hong, Ningning;Wu, Xiaotong;Chen, Yunyue
    • Wind and Structures
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    • v.30 no.4
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    • pp.405-421
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    • 2020
  • Quayside container cranes are important delivery machineries located in the most frontiers of container terminals, where strong wind attacks happen occasionally. Since the previous researches on quayside container cranes mainly focused on the mean wind load and static response characteristics, the fluctuating wind load and dynamic response characteristics require further investigations. In the present study, the aerodynamic wind loads on quayside container cranes were obtained from wind tunnel tests. The probabilistic and spectral models of the fluctuating aerodynamic loads were established. Then the joint probabilistic distributions of dynamic wind-induced responses were derived theoretically based on a series of Gaussian and independent assumption of resonant components. Finally, the results were validated by time domain analysis using wind tunnel data. It is concluded that the assumptions are acceptable. And the presented approach can estimate peak dynamic sliding force, overturning moments and leg uplifts of quayside container cranes effectively and efficiently.

Water Transport during the Single-pass Perfusion Experiments : Effects of Some Perfusates and Their Osmolality (일회통과 관류실험시 물의 수송 : 관류액의 종류와 삼투압의 영향)

  • 이정화;이현주;용철순;오두만
    • YAKHAK HOEJI
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    • v.39 no.4
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    • pp.411-416
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    • 1995
  • The single-pass perfusion experiments were performed in anesthetized rats to investigate the effects of perfusates and their osmolality on the water transport and to determine the correlation between the extent of water transport and the volume change of perfusate. Phenol red was used as a nonabsorbable marker. In normal rats, when perfused at a flow rate of 0.5 ml/min, 2-(N-rnorpholino) ethanesulfonic acid (MES) and S$\phi$rensen's phosphate buffers showed minimal net water transport as 0.125 and 0.173 %/cm of intestinal length, respectively. Hypotonic perfusate of 200 mOsm/kg of water and hypertonic perfusate of 400 mOsm/kg of water generated significant water transport compared with isotonic perfusate of 300 mOsm/kg of water. There was a linear correlation between the extent of water transport and the volume change of perfusate, suggesting that the volume change can be used as a measure of water transport.

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Water Vapor Transport Properties of Nonwoven Batting Materials (부직포 충전재의 수분투파성)

  • Kim, Hui-Suk;Na, Mi-Hui;Kim, Eun-Ae
    • Journal of the Korean Society of Clothing and Textiles
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    • v.22 no.1
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    • pp.72-79
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    • 1998
  • Journal of the Korean Society of Clothing and Textiles Vol. 22, No. 1 (1998) p. 72∼79 The purpose of this study was to investigate the effects of geometrical structure and fiber type on the water vapor transport properties of nonwoven batting materials. Two types of fiber were used such as polyester and wool. Correlation between physical properties of nonwovens and water vapor transport rate was analyzed by Pearson Correlation. Steady and dynamic state water vapor transport properties were measured by absorption, evaporation and cobaltots chloride method respectively. The results were as follows: 1) In geometrical structure, thickness of nonwovens was effected on absorption and evaporation rate and air permeability was more influencing factor on water vapor transport rate than porosity. There were no decreasing of water vapor transport rate in hydrophilic fiber at high relative humudity. 2) The hydrophilicity of fiber affected steady and dynamic state water vapor permeabilities and wool nonwoven showed higher water vapor transport rate than polyester at high relative humidity. 3) Thickness showed higher correlation coefficient with water vapor transport rate than other physical properties of nonwovens.

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A Study on International Trade of Water Transport Service using Social Network Analysis (소셜네트워크분석(SNA)을 활용한 수상운송서비스 무역 네트워크 분석 연구)

  • Seon-youl Park
    • Korea Trade Review
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    • v.47 no.3
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    • pp.75-92
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    • 2022
  • This study aims to analyze the International trade network of Water transport service using Social Network Analysis for defining the status of Korean Water transport industry. This study use World Input-Output Table of Asian Development Bank from 2000 to 2020 and build the International trade matrix of Water transport service from that. Therefore, this study analyze Out-degree centrality, In-degree centrality and betweenness centrality of Korea and other main countries in the matrix of World Water transport industry. As a result, Korea rank above 10th in the all centralities and the total output also rank 8th in the world, therefore, this study show the importance of Korean Water transport industry in the world. However, Singapore has the highest centrality in the world, even though China has the largest Total output among 63 countries.

The Change of Water Vapor Transport due to Global Warming (지구 온난화에 따른 물 수송 변화)

  • Oh, Hyun-Taik;Kim, Jeong-Woo;Shin, Ho-Jeong;Choi, Young-Jean
    • Journal of Korea Water Resources Association
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    • v.37 no.2
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    • pp.109-119
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    • 2004
  • This research is an analysis of the water vapor transport change Into the continent due to the global warming effect with the general circulation models. Water vapor transport change from ocean to land increases through the year due to CO2 doubling effect. In Eurasia, it indicates an increase about 170∼350${\times}$06 Mt/day the whole year. In Africa, it shows an decrease every month except November, especially there is the maximum decrease about -350${\times}$106 Mt/day during August-September. In other continents, excluding Eurasia and Africa, the change of water vapor transport vary with the month below $\pm$8.0${\times}$106 Mt/day with the unsystematic patterns. In Eurasia, the change of water vapor transport increases as a whole, but it decrease in desert areas which occupy a high area-ratio. Therefore, except desert areas, the amount of the growth in water vapor transport change concentrate on Asian monsoon area. As a result of monsoon strengthening, available water will grow considerably at the asian monsoon areas.

Change of Porosity and Water Vapour Transport Properties of Wool Fabrics by the Change of Moisture Regain and Fabric Structure (모직물의 수분율 변화와 구조에 따른 기공도 및 수분전달 특성변화)

  • 김동옥;나미희;김은애
    • Journal of the Korean Society of Clothing and Textiles
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    • v.23 no.6
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    • pp.820-828
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    • 1999
  • The purpose of this study was to investigate the changes of pore area and water vapour transport by the changes of moisture regain and fabric structure of wool fabrics, As specimens 4 worsted wool fabrics were used. The pore area were measured by image analysis method and dinamic vapour transport and water reisitance was determined by clothing-environment-body modelling system. The pore area was changed by the moisture regain of wool fabrics. The change of pore area was influenced by the yarn twist thread count and cover factor and the weave type. The water vapour transport was changed by the moisture regain. The change of water vapour transport was influenced by the change of pore aree which was determined by image analysis.

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Seasonal Volume Transport Variation and Origin of the Tsushima Warm Current

  • You, Sung-Hyup;Yoon, Jong-Hwan
    • Ocean and Polar Research
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    • v.30 no.2
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    • pp.193-205
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    • 2008
  • A model of the current and seasonal volume transport in the East China Sea was used to investigate the origin of the Tsushima Warm Current (TSWC). The modeled volume transport field suggested that the current field west of Kyushu ($30^{\circ}-32^{\circ}N$) was divided into two regions, R1 and R2, according to the bottom depth. R1 consisted of the Taiwan Warm Current (TWWC) region and the mixed Kuroshio-TWWC (MKT) water region, while R2 was the modified Kuroshio water (MKW) region west of Kyushu. The MKW branched from the Kuroshio and flowed into the Korea/Tsushima Straits through the Cheju-Kyushu Strait, contributing 41% of the annual mean volume transport of the TSWC. The TWWC and MKT water flowed into the Korea/Tsushima Straits through the Cheju-Kyushu and Cheju Straits, contributing 32% and 27% of the volume transport, respectively. The maximum volume transport of the MKW was 53% of the total volume transport of the TSWC in November, while the maximum volume transport of the water in the R1 region through the Cheju-Kyushu Strait was 41% in July. Hence, there were two peaks per year of volume transport in the TSWC.

Transport of Phenol in Waste Water Through Liquid Surfactant Membrane (폐수중 액체막에 의한 페놀의 이동)

  • 우인성;김병석;김윤선
    • Journal of the Korean Society of Safety
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    • v.5 no.3
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    • pp.39-43
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    • 1990
  • The transport of phenol from waste water through the liquid surfactant membrane containing Aliquat 336 as a carrier was analyzed by a theoretical model. Extraction experiments was carried out to investigate the effect of process parameters, such as mixing intensity, concentration of sodium hydroxide in internal aqueous solution, and counter anions, and initial phenol concentration in waste water at $25^{\circ}C$. It was found that transport rate of phenol increased with increasing pH differents. The transport rate of phenol in waste water was influenced by counter anions.

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The Effect of Geometrical Structure on the Moisture Transport Properties of Nonwoven Batting Materials (부직포 충전재의 구조적 특성이 수분전달 특성에 미치는 영향-단층구조와 이층구조 부직포의 비교-)

  • 김희숙;나미희
    • Journal of the Korean Society of Clothing and Textiles
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    • v.24 no.6
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    • pp.810-818
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    • 2000
  • The purpose of this study was to analyze the effect of geometrical structure on the moisture transport properties of nonwoven batting materials. Two types of nonwovens were used such as single and double layered nonwovens. Steady and dynamic state water vapor transport properties were measured by absorption, evaporation and cobaltous chloride method respectively. The results of this study were as follows: 1) Geometrical structure affected water vapor evaporation, but there were no differences between single and double layered nonwovens in moisture absorption. Thickness and air permeability were influencing factor on water vapor transport rate. 2) Directionality of double layered nonwoven was observed both in steady and dynamic state moisture transport. There were differences between upper and lower layer of double layered nonwoven both in moisture absorption rate and color change by cobaltous chloride method. 3) In dynamic state of water vapor transport rate, single layered nonwoven reached more rapidly at the established relative humidity. It was confirmed that geometrical structure affected water vapor evaporation and hydrophilicity of fiber affected moisture absorption because there were much more water vapor transport rate by evaporation than absorption within the same period of time.

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Evaluation Method for the Water Transport Properties of Sweat Absorbent Fabrics - Water Vapour Transport in the of Human-Clothing-Environment System - (첨단 흡수속건소재의 수분전달 특성 평가방법에 관한 연구 - 인체-의복-환경 System에서의 투습성 평가 -)

  • Kim, Eun Ae;Barker, Roger L.
    • Journal of the Korean Society of Clothing and Textiles
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    • v.17 no.2
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    • pp.329-338
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    • 1993
  • The purpose of this study was to design an instrument to simulate the Human-Clothing-Environment system and evaluate the water vapour transport properties of sweat absorbent PET fabrics. The instrument was composed of sweat generating part, clothing part which can simulate clothing layers, and enviromental part. As specimens, sweat absorbent PET, regular PET, cotton, nylon and acrylics fabrics were included. For the water vapour transport(WVT), relative humidities and temperatures were measured by film type humidity sensors and thermocouples, respectively. Water vapour pressures were calculated with measured RH's and temperatures. For the liquid water transport, wickability and demand wettability were measured. Results showed that there was a difference in terms of water vapour transport mechanism depending on the fiber type ; sweat absorbent PET showed higher WVT at the transient period then equilibrated, whereas other fabrics showed lower WVT at the transient period then increased continuously. These differences are expected to affect to the difference in the comfort properties of clothings. Sweat absorbent PET showed higher demand wettability and wickability than other fabrics. Wide application of the instrument was also suggested.

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