• Title/Summary/Keyword: Transport Equation

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Prediction of Crude Protein, Extractable Fat, Calcium and Phosphorus Contents of Broiler Chicken Carcasses Using Near-infrared Reflectance Spectroscopy

  • Kadim, I.T.;Mahgoub, O.;Al-Marzooqi, W.;Annamalai, K.
    • Asian-Australasian Journal of Animal Sciences
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    • v.18 no.7
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    • pp.1036-1040
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    • 2005
  • Near-infrared reflectance spectroscopic (NIRS) calibrations were developed for accurate and fast prediction of whole broiler chicken carcass composition. The Feed and Forage Foss systems Model 5000 Reflectance Transport Model 5000 with near-infrared reflectance spectroscopy (NIRS)-WinISI II windows software was used for this purpose. One equation was developed for the prediction of each carcass component. One hundred and fifty freeze dried broiler whole carcass samples were ground in a Cyclotech 1,093 sample mill and analyzed for dry matter, protein, fat, calcium and phosphate. Samples were divided into two sets: a calibration set from which equations were derived and a prediction set used to validate these equations. The chemical analysis values (mean${\pm}$SD) were calculated based on dry matter basis as follows: dry matter: 33.41${\pm}$2.78 (range: 26.41-43.47), protein: 54.04${\pm}$6.63 (range: 36.20-76.09), fat 35.44${\pm}$8.34 (range: 7.50-55.03), calcium 2.55${\pm}$0.65 (range: 0.99-4.41), phosphorus 1.38${\pm}$0.26 (range: 0.60-2.28). One hundred and three samples were used to calibrate the equations and prediction values. The software used was modified to obtain partial least square regression statistics, as it is the most suitable for natural products analysis. The coefficients of determination ($R^2$) and the standard errors of prediction were 0.82 and 1.83 for the dry matter, 0.96 and 1.98 for protein, 0.99 and 1.07 for fat, 0.90 and 0.30 for calcium and 0.91 and 0.11 for phosphorus, respectively. The present study indicated that NIRS can be calibrated to predict the whole broiler carcass chemical composition, including minerals in a rapid, accurate, and cost effective manner. It neither requires skilled operators nor generates hazardous waste. These findings may have practical importance to improve instrumental procedures for quick evaluation of broiler carcass composition.

Seasonal Variations of the Heat Flux in Muddy Intertidal Sediments near the Jebu Island during the Ebb Tides in the West Coast of Korea (서해 제부도 해역의 간조시 갯벌 퇴적층내 지온 및 열수지의 계절변화)

  • Na, Jung-Yul;Yu, Sung-Hyup;Seo, Jang-Won
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.5 no.1
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    • pp.1-9
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    • 2000
  • Vertical temperature distributions in muddy intertidal sediments near the Jebu Island on the west coast of Korea were obtained during the period of ebb tide which occurred in day time. The observations of mud temperature were made with thermistor embedded probe at 2cm interval for 18cm-layer of sediment for five different months of the year. Temporal changes in the vertical profile of the sediment temperature are strongly depend on the air temperature, the previous time of flood tide and the time of ebb tide. Heat exchanges in the surface layer (0-2 cm) in terms of magnitude and direction are greater than and opposite to those in the deeper sediment layer (8-12 cm), respectively and do not show any significant seasonal variations. In general, the surface layer gains heat while the deeper layer loses the heat. By using the 1-D diffusion equation temporal vertical profiles of the sediment temperature were obtained and were compared with the observed ones. The results show that in the sediment layer below 4 cm-depth the heat transport is predominantly by molecular diffusion. The average magnitude of heat flux into the sediment layer (0-18 cm) during the ebb tide when the mudflats were exposed in the middle of the day were between 4.1 and $28.9\;W/m^2$.

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Numerical Study of Evaporation and Ignition of in-line Array Liquid Droplets (액적 배열의 증발과 착화에 관한 수치해석적 연구)

  • 김충익;송기훈
    • Fire Science and Engineering
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    • v.13 no.1
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    • pp.37-47
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    • 1999
  • The spreading fire of very small floating particles after they are ignited is fast and t therefore dangerous. The research on this area has been limited to experiments and global simulations which treat them as dusts or gaseous fuel with certain concentration well m mixed with air. This research attempted micro-scale analysis of ignition of those particles modeling them as liquid droplets. For the beginning, the in-line array of fuel droplets is modeled by two-dimensional, unsteady conservation equations for mass, momentum, energy and species transport in the gas phase and an unsteady energy equation in the liquid phase. They are solved numerically in a generalized non-orthogonal coordinate. The single step chemical reaction with reaction rate controlled by Arrhenius’ law is assumed to a assess chemical reaction numerically. The calculated results show the variation of temperature and the concentration profile with time during evaporation and ignition process. Surrounding oxygen starts to mix with evaporating fuel vapor from the droplet. When the ignition condition is met, the exothermic reactions of the premixed gas initiate a and burn intensely. The maximum temperature position gradually approaches the droplet surface and maximum temperature increases rapidly following the ignition. The fuel and oxygen concentration distributions have minimum points near the peak temperature position. Therefore the moment of ignition seems to have a premixed-flame aspect. After this very short transient period minimum points are observed in the oxygen and fuel d distributions and the diffusion flame is established. The distance between droplets is an important parameter. Starting from far-away apart, when the distance between droplets decreases, the ignition-delay time decreases meaning faster ignition. When they are close and after the ignition, the maximum temperature moves away from the center line of the in-line array. It means that the oxygen at the center line is consumed rapidly and further supply is blocked by the flame. The study helped the understanding of the ignition of d droplet array and opened the possibility of further research.

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Numerical Analysis of Dynamic Response of Floating Offshore Wind Turbine to the Underwater Explosion using the PML Non-reflecting Technique (PML 무반사 기법을 이용한 부유식 해상풍력발전기의 수중폭발에 따른 동응답 수치해석)

  • Cho, Jin-Rae;Jeon, Soo-Hong;Jeong, Weui-Bong
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.29 no.6
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    • pp.521-527
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    • 2016
  • This paper is concerned with the numerical analysis of dynamic response of floating offshore wind turbine subject to underwater explosion using an effective non-reflecting technique. An infinite sea water domain was truncated into a finite domain, and the non-reflecting technique called the perfectly matched layer(PML) was applied to the boundary of truncated finite domain to absorb the inherent reflection of out-going impact wave at the boundary. The generalized transport equations that govern the inviscid compressible water flow was split into three PML equations by introducing the direction-wise absorption coefficients and state variables. The fluid-structure interaction problem that is composed of the wind turbine and the sea water flow was solved by the iterative coupled Eulerian FVM and Largangian FEM. And, the explosion-induced hydrodynamic pressure was calculated by JWL(Jones-Wilkins-Lee) equation of state. Through the numerical experiment, the hydrodynamic pressure and the structural dynamic response were investigated. It has been confirmed that the case using PML technique provides more reliable numerical results than the case without using PML technique.

Study on the Equation of Natural Period of Middle and Low Rise Building of Upper-Walled Lower Frame Type (중저층 상부벽식 하부골조 구조의 고유주기 산정식에 관한 연구)

  • Yoo, Suk-Hyeong
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.25 no.5
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    • pp.60-67
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    • 2021
  • According to the 「Guidelines of Structural Design for Piloti Building」 of the Ministry of Land, Infrastructure and Transport (2018), the natural period of middle and low rise building of upper-walled lower frame type, such as the domestic multiplex house in piloti style, is suggested for safety to apply the existing code formula of the wall structure. However, the current code formula of the wall structure was provided based on actual measurement of high-rise wall-type structures that mainly exhibit bending behavior. So it is considered that it is not suitable for a piloti-type house with four stories or less, where the wall behaves in shear. See also Park et al. (2000) confirmed that the effect of the lower frame part is greater than that of the upper wall part in the natural period of complex structures with 10 or more floors through analytical studies. Therefore, in this study, in order to examine the effect of the lower frame on the natural period of the middle and low-rise piloti structure, the estimation of natural period by the finite element analysis, approximation formula and ccurrent code formula was performed for the target structures with the shear and flexural stiffness of the upper wall and the shear stiffness of the lower frame as variables. As result, it was found that the change in the shear stiffness of the lower frame had a greater effect on the natural period of the whole building than the change in the bending or shear stiffness of the upper wall.

FEA Simulations on Water Absorption in Various Pre-Cracked Concretes (유한요소해석에 기반한 콘크리트 균열 조건에 따른 수분흡수 현상 분석)

  • Kim, Kun-Soo;Park, Ki-Tae;Kim, Jaehwan
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.25 no.5
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    • pp.68-75
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    • 2021
  • This study performed simulating water absorption in various pre-cracked concretes. 2D-Finite Element Analysis (2D-FEA) model was developed based on experimental results on the amount of absorbed water in concrete with the exposure time. Results from the 2D-FEA showed that both crack width and crack depth strongly affect the amount of absorbed water in cracked concrete. In addition, water absorption rate is introduced and a predictive equation is suggested to estimate the rate in order to quantify the amount of absorbed water in cracked concrete. It was confirmed that water absorption in concrete having less than 150 mm crack depth was dominated as a main transport factor regardless of crack width. Therefore, considering that steel corrosion caused by chlorides dissolved in water mainly occurs in reinforced concrete structures, it is necessary that crack depth as well as crack width should be investigated in reinforced concrete structures at the time of field-inspection.

Molecular Dynamics Simulation on the Thermal Boundary Resistance of a Thin-film and Experimental Validation (분자동역학을 이용한 박막의 열경계저항 예측 및 실험적 검증)

  • Suk, Myung Eun;Kim, Yun Young
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.32 no.2
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    • pp.103-108
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    • 2019
  • Non-equilibrium molecular dynamics simulation on the thermal boundary resistance(TBR) of an aluminum(Al)/silicon(Si) interface was performed in the present study. The constant heat flux across the Si/Al interface was simulated by adding the kinetic energy in hot Si region and removing the same amount of the energy from the cold Al region. The TBR estimated from the sharp temperature drop at the interface was independent of heat flux and equal to $5.13{\pm}0.17K{\cdot}m^2/GW$ at 300K. The simulation result was experimentally confirmed by the time-domain thermoreflectance technique. A 90nm thick Al film was deposited on a Si(100) wafer using an e-beam evaporator and the TBR on the film/substrate interface was measured using the time-domain thermoreflectance technique based on a femtosecond laser system. A numerical solution of the transient heat conduction equation was obtained using the finite difference method to estimate the TBR value. Experimental results were compared to the prediction and discussions on the nanoscale thermal transport phenomena were made.

A Study on the Current State of the Library's AI Service and the Service Provision Plan (도서관의 인공지능(AI) 서비스 현황 및 서비스 제공 방안에 관한 연구)

  • Kwak, Woojung;Noh, Younghee
    • Journal of Korean Library and Information Science Society
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    • v.52 no.1
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    • pp.155-178
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    • 2021
  • In the era of the 4th industrial revolution, public libraries need a strategy for promoting intelligent library services in order to actively respond to changes in the external environment such as artificial intelligence. Therefore, in this study, based on the concept of artificial intelligence and analysis of domestic and foreign artificial intelligence related trends, policies, and cases, we proposed the future direction of introduction and development of artificial intelligence services in the library. Currently, the library operates a reference information service that automatically provides answers through the introduction of artificial intelligence technologies such as deep learning and natural language processing, and develops a big data-based AI book recommendation and automatic book inspection system to increase business utilization and provide customized services for users. Has been provided. In the field of companies and industries, regardless of domestic and overseas, we are developing and servicing technologies based on autonomous driving using artificial intelligence, personal customization, etc., and providing optimal results by self-learning information using deep learning. It is developed in the form of an equation. Accordingly, in the future, libraries will utilize artificial intelligence to recommend personalized books based on the user's usage records, recommend reading and culture programs, and introduce real-time delivery services through transport methods such as autonomous drones and cars in the case of book delivery service. Service development should be promoted.

The Application of NIRS for Soil Analysis on Organic Matter Fractions, Ash and Mechanical Texture

  • Hsu, Hua;Tsai, Chii-Guary;Recinos-Diaz, Guillermo;Brown, John
    • Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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    • 2001.06a
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    • pp.1263-1263
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    • 2001
  • The amounts of organic matter present in soil and the rate of soil organic matter (SOM) turnover are influenced by agricultural management practice, such as rotation, tillage, forage plow down direct seeding and manure application. The amount of nutrients released from SOM is highly dependent upon the state of the organic matter. If it contains a large proportion of light fractions (low-density) more nutrients will be available to the glowing crops. However, if it contains mostly heavy fractions (high-density) that are difficult to breakdown, then lesser amounts of nutrients will be available. The state of the SOM and subsequent release of nutrients into the soil can be predicted by NIRS as long as a robust regression equation is developed. The NIRS method is known for its rapidity, convenience, simplicity, accuracy and ability to analyze many constituents at the same time. Our hypothesis is that the NIRS technique allows researchers to investigate fully and in more detail each field for the status of SOM, available moisture and other soil properties in Alberta soils for precision farming in the near future. One hundred thirty one (131) Alberta soils with various levels (low 2-6%, medium 6-10%, and high >10%) of organic matter content and most of dry land soils, including some irrigated soils from Southern Alberta, under various management practices were collected throughout Northern, Central and Southern Alberta. Two depths (0- 15 cm and 15-30 cm) of soils from Northern Alberta were also collected. These air-dried soil samples were ground through 2 mm sieve and scanned using Foss NIR System 6500 with transport module and natural product cell. With particle size above 150 microns only, the “Ludox” method (Meijboom, Hassink and van Noorwijk, Soil Biol. Biochem.27: 1109-1111, 1995) which uses stable silica, was used to fractionate SOM into light, medium and heavy fractions with densities of <1.13, 1.13-1.37 and >1.37 respectively, The SOM fraction with the particle size below 150 microns was discarded because practically, this fraction with very fine particles can't be further separated by wet sieving based on density. Total organic matter content, mechanical texture, ash after 375$^{\circ}C$, and dry matter (DM) were also determined by “standard” soil analysis methods. The NIRS regression equations were developed using Infra-Soft-International (ISI) software, version 3.11.

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Numerical Analysis of the Grand Circulation Process of Mang-Bang Beach-Centered on the Shoreline Change from 2017. 4. 26 to 2018. 4. 20 (맹방해빈의 일 년에 걸친 대순환과정 수치해석 - 2017.4.26부터 2018.4.20까지의 해안선 변화를 중심으로)

  • Cho, Young Jin;Kim, In Ho;Cho, Yong Jun
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.31 no.3
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    • pp.101-114
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    • 2019
  • In this study, we carry out the numerical simulation to trace the yearly shoreline change of Mang-Bang beach, which is suffering from erosion problem. We obtain the basic equation (One Line Model for shoreline) for the numerical simulation by assuming that the amount of shoreline retreat or advance is balanced by the net influx of longshore and cross-shore sediment into the unit discretized shoreline segment. In doing so, the energy flux model for the longshore sediment transport rate is also evoked. For the case of cross sediment transport, the modified Bailard's model (1981) by Cho and Kim (2019) is utilized. At each time step of the numerical simulation, we adjust a closure depth according to pertinent wave conditions based on the Hallermeier's analytical model (1978) having its roots on the Shield's parameter. Numerical results show that from 2017.4.26 to 2017.10.15 during which swells are prevailing, a shoreline advances due to the sustained supply of cross-shore sediment. It is also shown that a shoreline temporarily retreats due to the erosion by the yearly highest waves sequentially occurring from mid-October to the end of October, and is followed by gradual recovery of shoreline as high waves subdue and swells prevail. It is worth mentioning that great yearly circulation of shoreline completes when a shoreline retreats due to the erosion by the higher waves occurring from mid-March to the end of March. The great yearly circulation of shoreline mentioned above can also be found in the measured locations of shoreline on 2017.4.5, 2017.9.7, 2017.11.7, 2018.3.14. However, numerically simulated amount of shoreline retreat or advance is more significant than the physically measured one, and it should be noted that these discrepancies become more substantial for the case of RUN II where a closure depth is sustained to be as in the most morphology models like the Genesis (Hanson and Kraus, 1989).