• Title/Summary/Keyword: rational functions

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Separating and purifying polysaccharide, polypeptide from sea cucumber and their functions (해삼으로부터 다당류와 폴리펩타이드의 분리, 정제 및 기능성)

  • Jin, Hai-zhu;Fu, Xue-jun;Shen, Jing-yu;Sun, Bo;Wang, Hong-tao
    • Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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    • 2005.09a
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    • pp.112-123
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    • 2005
  • For thestudying and utilizing the thorn sea cucumber synthetically, the method preparing polysaccharide and polypeptide from sea cucumber was studied. The comparatively rational craft for preparing crude polysaccharide is fresh raw materials deal with oar form, $60\%$ of the ethanol precipitate after hydrolyzed by pretense and vibrated with ultrasonic wave auxiliary. The purification of polysaccharide and removal of protein fromcrude polysaccharide were made through precipitation method using the acetate. The polypeptide is obtained by concentrating in vacuum, freeze-drying after mixing precipitations of two times. Polysaccharide acute poisoning experiment indicate there is no bad reaction when LD50>5000g/kg, there strain rate of liver tumor H11 approach present generally acknowledged tumor treat medicine cyclophosphamide, and there is no side effect. The fatigue resistance function of polypeptide experiment also indicates that the fatigue resistance ability of mouse which fed on added sea cucumber polypeptide has a great improvement.

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Reliability Analysis of Storm Sewer System by AFOSM Method (AFOSM 방법에 의한 하수관망의 신뢰성 분석)

  • Kim, Mun Mo;Lee, Won Hwan;Cho, Won Cheol
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.13 no.2
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    • pp.201-209
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    • 1993
  • The purpose of this study is to analyze the reliability of storm sewer system and AFOSM method is applied on Sinjeong detention basin area to decide the applicability of AFOSM method. The Rackwitz Algorithm, which is suitable for minimizing the error due to non-linearity, is used to find the failiure point. The performance functions are established to calculate the risk, rational formula is used to determine the load and Manning equation and Darcy-Weisbach equation are used to determine the sewer capacity, and the results are 0.119, 0.127, respectively. The Risk-Safety Factor relation for each return period is derived and the designing of storm sewer system based on reliability analysis is enabled.

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Minimum life-cycle cost design of ice-resistant offshore platforms

  • Li, Gang;Zhang, Da-Yong;Yue, Qian-Jin
    • Structural Engineering and Mechanics
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    • v.31 no.1
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    • pp.11-24
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    • 2009
  • In China, the oil and natural gas resources of Bohai Bay are mainly marginal oil fields. It is necessary to build both ice-resistant and economical offshore platforms. However, risk is involved in the design, construction, utilization, maintenance of offshore platforms as uncertain events may occur within the life-cycle of a platform under the extreme ice load. In this study, the optimum design model of the expected life-cycle cost for ice-resistant platforms based on cost-effectiveness criterion is proposed. Multiple performance demands of the structure, facilities and crew members, associated with the failure assessment criteria and evaluation functions of costs of construction, consequences of structural failure modes including damage, revenue loss, death and injury as well as discounting cost over time are considered. An efficient approximate method of the global reliability analysis for the offshore platforms is provided, which converts the implicit nonlinear performance function in the conventional reliability analysis to linear explicit one. The proposed life-cycle optimum design formula are applied to a typical ice-resistant platform in Bohai Bay, and the results demonstrate that the life-cycle cost-effective optimum design model is more rational compared to the conventional design.

A performance-based design method for chloride-induced cover cracking of RC structures

  • Yang, Dong-Hui;Yi, Ting-Hua;Li, Hong-Nan
    • Computers and Concrete
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    • v.20 no.5
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    • pp.573-582
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    • 2017
  • Chloride-induced cover cracking will aggravate the performance deterioration for RC structures under the chlorideladen environment, which may endanger the safety of structures and occupants. Traditional design method cannot ensure that a definite performance is satisfied. To overcome the defects, a study on the performance-based design method was carried out in this paper. Firstly, the limit state functions were established for the corrosion initiation and cover cracking. Thereafter, the uncertainty analysis was performed to study the effects of random factors on the time-dependent performances. Partial factor formulae were deduced through the first-order reliability method for performance verification. Finally, an illustrative example was presented and the sensitivity of cover depth to other parameters was carried out. It is found that the uncertainties of the random variables have great effects on the required cover depth. It is demonstrated that the performance-based design method can ensure that the target performance can be satisfied and support to formulate a rational maintenance and repair strategy for RC structures under the chloride environment.

A study on the multi-functional fashion design - focused on the climatic change and environment consciousness- (다기능 패션디자인에 관한 연구 - 기후변화 및 환경의식을 중심으로 -)

  • Lee, Hyun-Young;Park, Hye-Won
    • Journal of Fashion Business
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    • v.13 no.2
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    • pp.123-135
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    • 2009
  • To cope with the threats posed by climate change actively, this study tries to examine multi-functional fashion design with the moral awareness of environment, which could be a direct cause of climate change. Literature and patents on multi-functional fashion design following climate change at home and abroad are examined to find the trend of multi-functional fashion designs. And fashion design that can protect human body to cope with climate change is analyzed. This study found that first, it is necessary to recognize the environment problems in the design process so that material is used to the minimum to minimize pollution and enable welfare and continuation of human society; second, environmentally friendly production and rational consumption such as manual production without waste of energy and material need to be favored to minimize the destruction of environment; third, to cope with environment and climate changes, design that allows an item to have diverse functions is needed so that it can have varied lengths, widths, and thicknesses, and it can be put on and taken off.

Surface Deformation by using 3D Target Curve for Virtual Spatial Design (가상 공간 디자인을 위한 3차원 목표곡선을 이용한 곡면 변형)

  • Kwon, Jung-Hoon;Lee, Jeong-In;Chai, Young-Ho
    • Journal of KIISE:Software and Applications
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    • v.33 no.10
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    • pp.868-876
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    • 2006
  • 2D input data have to be converted into 3D data by means of some functions and menu system in 2D input modeling system. But data in 3D input system for virtual spatial design can be directly connected to the 3D modeling data. Nevertheless, efficient surface modeling and deformation algorithm for the 3D input modeling system are not proposed yet. In this paper, problems of conventional NURBS surface deformation methods which can occur when applied in the 3D input modeling system are introduced. And NURBS surface deformation by 3D target curves, in which the designer can easily approach, are suggested. Designer can efficiently implement the virtual spatial sketching and design by using the proposed deformation algorithm.

A Study on the Application building Scope for the Mixed-Use Districts (복합용도지역의 건축물 규모의 운용방안에 관한 연구)

  • Lee, Won-Geun;Kim, Young-Chan
    • Journal of The Korean Digital Architecture Interior Association
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    • v.10 no.1
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    • pp.65-74
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    • 2010
  • This study has been given careful consideration to an induction of the mixed-use districts for the efficiency of Land Use, the rational plot planning and the mixture/complex among the functions in order to complement the zoning plan with the primary purpose to purify the usage of landscape. Furthermore, it is aimed to indicate the implementations through the medium of the in-depth analysis about the cardinal factors such as the standards on the regional location, building size and building uses in the case of designating the Mixed-use districts.Abstract This study has been examined by the aspect of scope for securing the adequacy of Site Division Restriction, Floor Area Ratio, Building Coverage Ratio and Outdoor Area Ratio in the "Mixed-Use Districts" and especially, by the medium of the in-depth analysis about the actual condition of building and outdoor space scales. It has been deduced the scale standards by using the simulation and correlation analysis among the factors of those buildings and outdoor spaces. Moreover, it has been applied the analysis method of using the building scale, especially, the latter has analyzed the total 1,656 different types classified by 3 patterns of Plottage and Building Coverage Ratio, 9 patterns of the factor change on Outdoor Area Ratio and 8 different patterns of road width.

A Study on the Train Composition Requirements for Safety Operation of Urban-Transit (도시철도 안전운행을 위한 열차 구성요건에 관한 연구)

  • Jeon, Young-Seok;Lee, Hi-Sung;Wang, Jong-Bae
    • Journal of the Korean Society for Railway
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    • v.14 no.1
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    • pp.66-72
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    • 2011
  • In order to assure the safety of train operation, a safety function analysis corresponding hazardous events of railway accidents and a safety requirement review on operation & management of trains have been performed. The preconditions and train composition requirements such as safety principles and functions that should be essentially considered to enable the safety operation of Urban-Transit trains are clearly presented. On the basis of presented train composition requirements, a rational revise of Urban Railway Operation Rule is proposed. It will be helpful in accident prevention and safety improvement for railway operation.

Probabilistic Analysis of Lifetime Extreme Live Loads in Office Buildings (사무실의 사용기간 최대 적재하중에 대한 확률론적 분석)

  • 김상효;조형근;배규웅;박흥석
    • Computational Structural Engineering
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    • v.3 no.1
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    • pp.109-116
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    • 1990
  • Live load data in domestic office buildings have been collected in a systematic manner. Based on surveyed data, equivalent uniformly distributed load intensities, which produce the same load effect as the actual spatially varying, live load, have been obtained for various structural members (such as slab, beam, column, etc. ). Influence surface method has been employed to compute load effects under real live load, including beam moment, slab moment as well as axial force in column. The results have been examined to find probabilistic characteristics and relationship between influence area and load intensity (or coefficient of variation). The results were also compared with other survey results and found to be reasonable. Based on the probabilistic load models obtained, the lifetime extreme values have been analyzed and compared with current design loads. Tentative equations applicable to decide more rational design loads are also suggested as functions of influence area.

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Modal strength reduction factors for seismic design of plane steel frames

  • Papagiannopoulos, George A.;Beskos, Dimitri E.
    • Earthquakes and Structures
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    • v.2 no.1
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    • pp.65-88
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    • 2011
  • A new method for the seismic design of plane steel moment resisting frames is developed. This method determines the design base shear of a plane steel frame through modal synthesis and spectrum analysis utilizing different values of the strength reduction (behavior) factor for the modes considered instead of a single common value of that factor for all these modes as it is the case with current seismic codes. The values of these modal strength reduction factors are derived with the aid of a) design equations that provide equivalent linear modal damping ratios for steel moment resisting frames as functions of period, allowable interstorey drift and damage levels and b) the damping reduction factor that modifies elastic acceleration spectra for high levels of damping. Thus, a new performance-based design method is established. The direct dependence of the modal strength reduction factor on desired interstorey drift and damage levels permits the control of deformations without their determination and secures that deformations will not exceed these levels. By means of certain seismic design examples presented herein, it is demonstrated that the use of different values for the strength reduction factor per mode instead of a single common value for all modes, leads to more accurate results in a more rational way than the code-based ones.