• Geomechanics and Engineering
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• 제22권6호
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• pp.519-528
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• 2020

A mathematical wetting model is usually used to predict the deformation of core wall rockfill dams induced by the wetting effect. In this paper, a series of wetting triaxial tests on a rockfill was conducted using a large-sized triaxial apparatus, and the wetting deformation behavior of the rockfill was studied. The wetting strains were found to be related to the confining pressure and shear stress levels, and two empirical equations, which are regarded as the proposed mathematical wetting model, were proposed to express these properties. The stress and deformation of a core wall rockfill dam was studied by using finite element analysis and the proposed wetting model. On the one hand, the simulations of the wetting model can estimate well the observed wetting strains of the upstream rockfill of the dam, which demonstrated that the proposed wetting model is applicable to express the wetting deformation behavior of the rockfill specimen. On the other hand, the simulated additional deformation of the dam induced by the wetting effect is thought to be reasonable according to practical engineering experience, which indicates the potential of the model in dam engineering.

• Smart Structures and Systems
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• 제21권1호
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• pp.123-137
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• 2018

Structural monitoring is the most important part of the construction and operation of the embankment dams. Appropriate instruments selection for dams is vital, as inappropriate selection causes irreparable loss in critical condition. Due to the lack of a systematic approach to determine adequate instruments, a framework based on three comparable Multi-Attribute Decision Making (MADM) methods, which are VIKOR, technique of order preference by similarity to ideal solution (TOPSIS) and Preference ranking organization method for enrichment evaluation (PROMETHEE), has been developed. MADM techniques have been widely used for optimizing priorities and determination of the most suitable alternatives. However, the results of the different methods of MADM have indicated inconsistency in ranking alternatives due to closeness of judgements from decision makers. In this study, 9 criteria and 42 geotechnical instruments have been applied. A new method has been developed to determine the decision makers' importance weights and an aggregation method has been introduced to optimally select the most suitable instruments. Consequently, the outcomes of the aggregation ranking correlate about 94% with TOPSIS and VIKOR, and 83% with PROMETHEE methods' results providing remarkably appropriate prioritisation of instruments for embankment dams.

• Environmental Engineering Research
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• 제15권2호
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• pp.99-103
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• 2010

Integrated management systems (IMS) that control entire sewerage facilities in the upper reaches of multi-purpose dams are being constructed for their efficient operation and management. However, because the IMS installed in a watershed belong to several local government bodies, significant conflict would be expected between stakeholders in the process of deciding who should control the IMS after completion of the construction that was initially implemented under the support of central government. The objective of this study was to suggest a decision making to determine who should control the IMS for sewerage facilities in the upper reaches of multipurpose dams in Korea, using the analytic hierarchy process (AHP). Three alternatives were selected to determine who should control the IMS for sewerage facilities: commissioning to public corporations, commissioning to private corporations, and a role-sharing partnership. In using the AHP technique, the emphasis was on comparing public interests, economics, efficiency, sustainability, specialty, grievance mediation and receptiveness. As a result, building a role-sharing partnership received the highest score. Commissioning to a special institute was also suggested as an alternative as this showed a score similar to that of building a role-sharing partnership.

• 대한수의학회지
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• 제30권3호
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• pp.343-348
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• 1990

Total 51 calves born from both 28 seropositive and 23 seronegative dams were subjected to study both prenatal and postnatal infections of bovine leukemia virus (BLV), and the duration of passive colostral antibody by means of immunodiffusion (ID) test. All calves were tested for precolostral and postcolostral periods by 16 months of age. The results were as follows: 1. Of 28 precolostral sera of the calves born from infected dams, one appeared positive, indicating in utero BLV infection from the dam. 2. BLV-antibody test for the postcolostral sera of the calves born from seropositive or seronegative dams showed that the colostral antibody of the calves disappeared from 2 to 6 months of age, and the increase of the number of seropositive calves initiated from 3 to 4 months of age indicated postnatal infection.

• Biomolecules & Therapeutics
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• 제4권4호
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• pp.339-348
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• 1996

A new composite antibiotic, SM-101 (sulbactam·metampicillin), was at dose levels of 0, 250, 500 and 1000 mg/kg/day administered intravenously to pregnant and subsequently delivered Sprague-Dawley rats from day 17 of gestation to day 21 of lactation. Effects of test agent on dams and growth, behaviour and mating performance of Fl offspring were examined. In dams, one death occurred at 1000 mg/kg. The increase in kidney weight of the 250, 500 and 1000 mg/kg group was found. In F1 offspring, both delayed incisors eruption and decreased body weight were observed in females of the 1000 mg/kg group. The increase in the weights of liver and kidney was found in males of the 1000 mg/kg group. No treatment-related abnormalities were observed in each treated group in terms of behaviour and reproductive performance. In F1/F2 fetuses, no drug-induced abnormalities occurred at all doses tested. The results show that the no effect dose level (NOEL) of SM-101 is under 250 mg/kg/day for dams and 500 mg/kg/day for F1 offspring, and over 1000 mg/kg/day for F1/F2 fetuses.

• Biomolecules & Therapeutics
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• 제9권4호
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• pp.311-317
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• 2001

YHB6211, a newly developed recombinant human granulocyte colonystimulating factor, was administered at dose levels of 0, 3, 15, and 75 $\mu$g/kg/day intravenously to the pregnant New Zealand White rabbits (20 rabbits per group) during the organogenetic period, days 6 to 18 of gestation. All dams were subjected to Caesarian section on day 28 of gestation and their fetuses were examined for external, visceral, and skeletal abnormalities. No abnormalities in clinical signs, body weight changes, gross findings, mortality, and external appearance were found in all dams and fetuses exposed to 0, 3, and 15 $\mu$g/kg/day of YHB6211. However, in the group treated with 75 $\mu\textrm{g}$/kg/day of YHB6211, maternal body and uterine weights, fetal body weights and length, and the number of live fetuses were significantly decreased and further fetal mortality was remarkably increased. It is suggested that YHB6211 may have no side effect up to the dose level of 15 $\mu$g/kg/day, and there would be no teratogenicity for fetuses of rabbits up to 75 $\mu\textrm{g}$/kg/day even if it may have some toxic effects over 75$\mu\textrm{g}$/kg/day for dams and fetuses of rabbits.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2004년도 학술발표회
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• pp.563-567
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• 2004

During drought season, the self-purification capacities of the four major rivers in Korea are significantly controlled by environmental maintenance flows supplied from the mid- or upstream large dams. Therefore, it is obviously important to operate the dams considering not only water quantity aspects but also conservation of downstream water quality and aquatic ecosystems. Mathematical water quality models can be efficiently used to serve as a decision support tool for evaluating the effects of operational alternatives of upstream dams on the downstream aquatic environment. In this study, an unsteady one-dimensional water quality model, KORIV1-WIN was developed based on the theoretical and numerical algorithms for hydrodynamics and water quality simulations of CE-QUAL-RIV1. It consists of hydrodynamic(KORIV1H) and water quality(KORIV1Q) modules, and pre- and post-processors for input data preparations and output displays. The model can be used to predict one-dimensional hydraulic and water quality variations in rivers with highly unsteady flows such as dam outflow change, rainfall-runoff, and chemical spill events.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2009년도 세계 도시지반공학 심포지엄
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• pp.1017-1024
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• 2009

In the past few decades, the rockfill embankment dam, which has superior workability and economy, has become a major trend. In Korea, most of the embankment dams are rockfill dams, but recently, in response to the demand for sustainable development and environmentally-friendly water resource development, the sand and gravel in streams has become a major construction material for dams, rather than the non-economic rockfill, and its application examples have also increased. In this study, a large triaxial test was performed, with construction samples of different maximum sizes, in parallel with the grading method at the 'B Dam' construction site in Korea, and the effects of the different maximum sizes on the strain of the dam construction material and on the shear strength characteristics were analyzed to provide the basic data for determining the strength characteristics of the coarse-grained materials by the maximum size.

• 한국실내디자인학회논문집
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• 제18권3호
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• pp.93-101
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• 2009

Nowadays, the constructions of dams are being issued by the public due to the preservation and protection of nature considered more important than development. These social phenomenon can not be evitable due to arguing the both attitudes, preservation and development of nature. However, There are possibilities to make an agreement with the compromise between the two sides. The common goals of the attitudes are concerning human beings and their life quality. In this atmosphere, the exhibition hall of dams is very important to lead the agreement of both groups because the spaces not only provide contents to compromise by showing positive factors of dams, but present condition of using water as natural resources. The purpose of this study is based on the effect of the applied media in an exhibition hall as presenting education and enlightenment factors. To examine the effect, this study categorizes the existing media by communication types firstly. Secondly, based on the categorization, existing media of each dam exhibition hall are analyzed by numerical way. Thirdly, the general characteristics of applied media are defined by integrating the spatial contents and media. The data from the study are effective to provide the basic data for following design works for the exhibition space.

• Computers and Concrete
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• 제16권3호
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• pp.429-448
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• 2015

The dams are huge structures storing a large amount of water and failures of them cause especially irreparable loss of lives during the earthquakes. They are named as a group of structures subjected to fluid-structure interaction. So, the response of the fluid and its hydrodynamic pressures on the dam should be reflected more accurately in the structural analyses to determine the real behavior as soon as possible. Different mathematical and analytical modelling approaches can be used to calculate the water hydrodynamic pressure effect on the dam body. In this paper, it is aimed to determine the dynamic response of concrete gravity dams using different water modelling approaches such as Westergaard, Lagrange and Euler. For this purpose, Sariyar concrete gravity dam located on the Sakarya River, which is 120km to the northeast of Ankara, is selected as a case study. Firstly, the main principals and basic formulation of all approaches are given. After, the finite element models of the dam are constituted considering dam-reservoir-foundation interaction using ANSYS software. To determine the structural response of the dam, the linear transient analyses are performed using 1992 Erzincan earthquake ground motion record. In the analyses, element matrices are computed using the Gauss numerical integration technique. The Newmark method is used in the solution of the equation of motions. Rayleigh damping is considered. At the end of the analyses, dynamic characteristics, maximum displacements, maximum-minimum principal stresses and maximum-minimum principal strains are attained and compared with each other for Westergaard, Lagrange and Euler approaches.