Dam Type Research Articles

Incidence of infection in 39-month-old ewes with TMEM154 diplotypes "1 1," "1 3," and "3 3" after natural exposure to ovine progressive pneumonia virus.

Production and well-being of sheep and goats in many countries are harmfully impacted by small ruminant lentiviruses (SRLV) that cause incurable, progressive diseases. Susceptibility to ovine progressive pneumonia virus (OPPV), the North American form of SRLV, is influenced by variants of the ovine transmembrane protein 154 gene (TMEM154). The experimental objective was to estimate additive and dominance effects of TMEM154 haplotypes 1 and 3 on susceptibility of breeding ewes to infection after natural exposure to OPPV from birth to 39 mo of age. Sires and dams were heterozygous for TMEM154 haplotypes 1 and 3, producing ewe lambs with diplotypes "1 1," "1 3," and "3 3." These lambs were raised by mature, infected dams to ensure natural, maternal exposure to OPPV. Ewe lambs (n = 108) were kept for breeding and joined an infected flock of ewes to guarantee natural, nonmaternal exposure to OPPV. Ewes were bred to lamb at 1, 2, and 3 yr of age. Serum samples were collected at breeding, 1 mo before lambing and shortly after weaning each year to monitor infection status to 39 mo of age. During the experiment, 9 of the 108 ewes died while uninfected and data collected on these ewes were not analyzed. Infection status of the remaining 99 ewes at 39 mo of age was analyzed using logistic regression procedures. Effects of ewe type of birth, ewe type of rearing, and breed type of dam were not detected (P > 0.10), and the estimated sire variance component was nil. Ewe diplotype affected infection status (P < 0.0001), as did additive (P < 0.0001) and dominance (P < 0.0022) effects. Predicted probabilities of infection for ewes with diplotypes "1 1," "1 3," and "3 3" were 0.10, 0.88, and 0.89, respectively, and confidence intervals for diplotypes "1 3" and "3 3" were distinct from "1 1." Haplotype 3 was completely dominant to haplotype 1 at 39 mo of age. The probability of infection for ewes with either diplotype "1 3" or "3 3" averaged 8.5 times that of ewes with diplotype "1 1." Diplotype "1 3" and "3 3" ewes were highly susceptible to nonmaternal transmission of OPPV, in contrast to diplotype "1 1" ewes. Therefore, the distribution of ewes with diplotypes "1 1," "1 3," and "3 3" within a flock will influence the number of infections caused by each route of transmission. Selection and mating strategies can be implemented to produce sheep that are genetically less susceptible to OPPV infection.

On One Class of Boundary Value Problems of the Steady-State Filtration Theory in Porous Grounds

:In the framework of Darcy's law of filtration the investigation results of one class of boundary value problems of the steady-state filtration theory in porous ground base are presented. The plane mixed bounadry value problems on the structural analysis of hydrotechnical con­struction of dam type on filtrating ground base in the form of a layer of finite or infinite thickness are considered. The coefficient of filtration is assumed to be constant, piecewise constant, or changing by the depth of base according to the exponential law, the property of anisotropy of filtration is also taken into account. Axis-symmetric and three-dimentional boundary value problems of the theory of steady-state fluid filtration in a three-dimentional layer of a finite or infinite thickness are discussed. These problems are of the type of Lamb well-known hydrodynamic problems in the theory of steady-state flow of the ideal fluid, when through the circular or rectangular openeing of a rigid screen on the upper bound of the layer the liquid with a definite vertical velocity or with a definite pressure is injected into porous ground base. Here, the fields of velocities and pressures in the layer, as well as flow rates of liquid through the certain sections of the ground base are determined.

논산천의 서식처 유형별 어류군집의 분포특성

The spatial distribution characteristic of fish community were investigated at the 10 habitat types in the Nonsan stream from August, 2008 to June, 2009. The collected species during the surveyed period were 26 species belong to 6 families. Korean endemic species were Sarcocheilichthys nigripinnis morii, Squalidus japonicus coreanus, Hemiculter eigenmanni, Pseudobagrus koreanus, and Odontobutis interrupta which showed 19.2% ratio of total species. Dominant species was Zacco platypus, and subdominant species was Tridentiger brevispinis. Dominant species according to habitat types were Micropterus salmoides(substrate type pool and rock type pool), Lepomis macrochirus(channel connected pool and channel unconnected pool/abandoned type pool), T. brevispinis(channel unconnected pool/overflow type and run) and Z. platypus(riffle, meander type pool, side channel, and dam type pool). As a results of community analysis in side channel, diversity index showed relatively high values, indicating that habitat types in the Nonsan stream have relatively stable community structure. Bray-curtis cluster analysis indicated that the meander type pool and riffle showed the most similar values(80.8%). Moreover, cluster and principal component analysis were classified as 2 groups(lotic and lentic habitats).

Piezometric variations in the basaltic massif beneath the Itaipu hydroelectric plant (Brazil/Paraguay border): Right Buttress Dam

This article describes a case study of the changes in the hydrogeotechnical behavior of a portion of the foundation block of the Itaipu Dam, which is located on the Parana River on the border between Brazil and Paraguay. The study focuses on the foundation buttress blocks of the Right Buttress Dam, where the most permeable regions of the massif are monitored by standpipe piezometers. The behaviors of two features within the basalt layers, a basaltic breccia and a fracture, were evaluated. In general, the uplift pressure distribution models of the foundations of concrete dams only consider the hydraulic loads caused by the presence of the reservoir and the tailwater elevation. However, this study demonstrates that the hydrogeotechnical behavior of the massif in a given period may also depend on the local variation in rainfall. The primary conclusion is that although the rocky massif has received several foundation treatments (waterproofing and drainage work), the natural hydraulic conditions of the massif govern the pressure variations within the monitored features. Studying the behavior of these features is of fundamental importance to all large concrete dams, as a statistical analysis of ruptures in several types of dams conducted by the International Commission on Large Dams has demonstrated that accidents involving this type of dam are primarily caused by foundation collapse, particularly by collapses related to internal erosion problems and low shear resistance.

Total Risk Rating and Liquefaction Analysis of Farrokhi Earth Embankment Dam, Eastern Iran

Farrokhi earth embankment dam is located near Qayen in one of the most active seismic regions of Iran (Ferdows seismic state). Due to presence of large active faults in the area, like Dashte-Bayaz and Abiz faults, it is necessary to obtain the total risk rating of the dam and to evaluate the liquefaction potential of the soil layer beneath the dam foundation. The total risk for embankment dam structures depends on two factors, i.e., (i) the seismic hazard rating of the dam site, and, (ii) the risk rating of the dam and appurtenant structures. Bureaue’s method of total risk analysis is used in this paper. Applying this method to Farrokhi dam, the risk factors are determined from different aspects i.e., dam type, age, size, and downstream risk potential. The total risk factor is then determined by considering the effects of each factor as well as seismic vulnerability rating of the dam site. Liquefaction, defined as the transformation of a granular material from a solid to a liquefied state, is a common hazard for civil infrastructures at the time of major earthquakes. In the present study, the procedure recommended by Youd et al. (J Geotech Geoenviron Eng ASCE, 127(10):817–833, 2001), based on SPT results were used. Results of the field geotechnical investigation program carried out on the dam foundation, including SPT data, were used in the liquefaction analysis. Ground motion parameters required in the analysis, i.e. peak horizontal acceleration (amax), were calculated after a careful study of the active faults in the region. Based on the findings of the present study, the alluvial foundation is liquefiable to 3 m of depth in some regions and remedial measures should be taken in advance. An elaborate stability analysis of the dam embankment is deemed necessary.

THE HISTORIC KURIT DAM: AN ILLUSTRATIVE EXAMPLE OF WATER WISDOM

ABSTRACTThe historic Kurit Dam near Tabas, Iran, has regulated the Kurit River for irrigation for 600 years and can be considered a symbol of sustainability. The arch‐gravity dam is especially remarkable for its extraordinary height of 60 m. This was to remain a world record for any type of dam from 1350 until the early twentieth century. The former president of ICOLD referred to the Kurit Dam as one of the most astounding achievements in dam engineering in the Middle Ages. Despite the fact that the dam was built 650 years ago, it still serves as an illustrative example of creativity, harmony with floods, sustainable development and coping with uncertainties.Unfortunately overlooking the valuable water wisdom of past generations, a modern dam was constructed just upstream of the historic dam. When, 6 years after impoundment, the new dam remained virtually empty due to error in estimating the river inflow, the canniness of the builders of the old dam became evident.This paper seeks to reveal the engineering genius of Iranian history to provide an example of the intergenerational and multicultural collaboration demanded by the global climate challenges of today. Copyright © 2014 John Wiley &amp; Sons, Ltd.

Impact of dams on distribution, population structure, and hybridization of two species of California freshwater sculpin (Cottus)

Dams represent a beneficial way to maximize riverine potential, though the benefits often come with costs. Modified conditions to rivers downstream of dams (release temperature, flow, barriers to migration) can lead to changes in species compositions. In California, these effects are amplified, as limited water resources lead to extensive anthropogenic changes. Our study examined the role of seven western Sierra Nevada river dams on localized distribution and population structure of native riffle sculpin (Cottus gulosus) and their role in potential hybridization with native prickly sculpin (C. asper). Individuals were collected above and below dams, genotyped with 10 microsatellite loci, and analyzed for possible hybridization. Three downstream locations (American, Tuolumne, and Kings River) support populations of both species whereas the remaining downstream sites supported only prickly sculpin. River specific genetic population structure was found for both species but was more extensive in riffle sculpin. Hybridization was limited to the Kings River, and represented less than 3 % of individuals sampled. Comparisons between dams including elevation above sea level, type of dam, distance from dam to sampling location, and average released water temperature showed no correlation with riffle sculpin presence below a dam. Expanded sampling within the Kings River found no association with distance and riffle sculpin or hybrid presence, although both were limited to recent trout restoration areas. Therefore, despite initial inclinations, dams show no direct correlation with sculpin distributions or hybridization in the Great Central Valley of California.

Nutritional background, sire type and dam type affect saturated and monounsaturated (oleic) fatty acid concentration of lambs reared for meat production in Australia

This study investigated the effect of finishing diet, sire type and dam type on major saturated (C12:0, 14:0, 16 : 0 and 18:0) and monounsaturated (oleic; C18:1cis) fatty acid concentrations in meat from lambs grown at eight production locations across Australia. Sires were selected from Merino, maternal and terminal meat breeds; while the dams consisted of ~80% pure Merino and 20% crossbred (Border Leicester × Merino) types. Lambs were generally maintained under extensive pasture conditions, but were fed grain, hay or feedlot pellets when the pasture supply was limited. Lambs were slaughtered over 3 consecutive years (2008–10), with 28–30 slaughter days per year. At 24 h post-mortem, 20-g muscle samples (longissimus lumborum: LL) were taken for fatty acid determination. Lambs from Hamilton, Katanning and Kirby had a higher (P &lt; 0.001) concentration of major saturated (palmitic and stearic) and oleic acids in meat that is proposed to be associated with those lambs being fed diets higher in cereal grain content. Saturated fatty acids, except lauric acid, were lower (P &lt; 0.02) in lambs sired by Merino or terminal type than lambs sired by maternal type. The use of Merino as the sire or dam reduced (P &lt; 0.001) the major saturated fatty acids in LL. Crossbred dam type increased (P &lt; 0.01) the oleic acid concentration in the LL, but sire type had no effect. The results demonstrate that the finishing diet type or sire type or dam type can significantly influence the concentration of major saturated (palmitic, stearic) and/or oleic acids in meat from lambs produced under different production systems in Australia.

Influence of Different Rubber Dam Application on Intraoral Temperature and Relative Humidity

The purpose of this study was to investigate the effect of type of rubber dam and application method on the moisture exclusion effect. The intraoral temperature and relative humidity were compared among various moisture exclusion appliances. Various dry field techniques were applied to 5 subjects and intraoral temperature and relative humidity measured 5 min after placing a digital hygro-thermometer in the mouth. The relative humidity was 100% in all subjects when moisture was excluded by means of cotton rolls alone. When only tooth 36 was exposed, relative humidity was significantly lower with latex, urethane, or 3-dimensional sheets than with cotton rolls alone, and was similar to the level of humidity in the room. When a local rubber dam was used, the relative humidity was significantly higher than the indoor humidity (p<0.05). No significant differences were noted in the intraoral temperature or relative humidity between exposure of 4 teeth and 1 tooth, but variation in the relative humidity was more marked in 4- than in 1-tooth exposure. The creation of an air vent did not influence the moisture exclusion effect. These results suggest that the rubber dam isolation technique excludes moisture to a level equivalent to the humidity in the room when only a single tooth is exposed, but the moisture exclusion effect may be inconsistent when several teeth are exposed.

Using real-time abnormal hydrology observations to identify a river blockage event resulted from a natural dam

This study proposes an automatic identification approach for landslide dam formation using a real-time abnormal hydrology record and artificial neural network (ANN). In Taiwan, natural dams occur frequently and have the potential to cause significant disasters, especially in the presence of fragile geological conditions such as steep mountains, earthquakes, intense typhoon, and storm events. During a river blockage event, obtaining immediate real-time information can be difficult or even impossible due to extreme weather conditions, remote locations, and the mountainous terrain of the area. As a result of these issues, there is a strong need for a practical tool that can not only detect the occurrence of this type of natural dam but also estimate the potential real-time risk of dam failure. In order to develop the appropriate safety response, a rapid preliminary assessment of the failure type must be identified, followed by a thorough investigation into the failure process after the event has occurred. In this study, a new method is developed that applies an ANN model (1) to evaluate, in real time, the occurrence of a natural dam and the storage changes behind that dam; (2) to rapidly assess the natural dam failure type and failure process; and (3) to reconstruct the dam height variation during the dam failure process after the event. The proposed methodology is applied to Chi-Shan River Basin located in Kaohsiung, Taiwan, during Typhoon Morakot in 2009. In 3 days, Typhoon Morakot produced 1,911 mm of precipitation. The typhoon event produced a landslide dam and a debris flow that inundated Hsiaolin Village, causing 398 deaths. The tragic results of this case study demonstrate the need for an applicable, accurate, and efficient method to evaluate dam formation and its failure rate.

Analysis on Progressive Slipping-Shear Failure Mode of Bedding Slope of Hard Rock with Medium or Large Dip Angle

Kala Hydropower Station is located in the midstream of Yalong River in Sichuan Province of China, and the type of dam is concrete gravity dam, with a largest dam height of 129 m, an installed capacity of 1000 MW and a storage capacity of 255.8 million cubic meters. The slope on the right bank of the dam site is mainly composed of hard metasandstone and marbles interbedded with carbonaceous slates and the dip of rock formation is the same as the aspect of slope, so that it is a typical bedding slope. The field survey indicates that the failure of bedding slope of hard rock is not on a common mode of slipping-bending or buckling, but on an uncommon failure mode. The paper introduces a research method that starts with geologic history, analyzes current state and predicts the future failure mode, analyzes the characteristics and phenomenon of slope failure, and adopts the finite element calculation method to analyze the plastic zone resulting from slope deformation. According to the deformation evidence and calculation results, the engineering geologic mechanical theory is used to analyze the deformation and failure mode of slope, and it is indicated that the current and future failure modes of hard rock slope with large thickness are all slipping-shear failure.

Static Performance of Face Rockfill Dam on the Principle of Finite Element

The concrete face rockfill dam has a strong ability to adapt to the terrain and geological conditions, which is a good choice of dam type for easy construction, short constructed period, safe and good shock resistance. Therefore, the study of stress and deformation in the completion date, normal water level and rapid drawdown is of very important in significance. In this paper, a face rockfill dam is studied by the finite element method.

Coupled stress–seepage analysis of Karun III concrete arch dam

The response of a concrete arch dam is very much affected by the mechanisms of foundation rock behaviour. This type of dam is highly sensitive to displacements of its foundation owing to the low stiffness of the dam compared to the displacements of its foundation and abutments. Seepage is a load type which is distributed widely within foundation rock. Therefore, it could have important effects on displacements and stresses in the dam. In this paper, the Karun III double-curvature, 205 m high arch dam is selected as a case study. Effective stress analyses are carried out for the dam. The analysis results are compared with values recorded by instruments. Furthermore, the effects of some basic input parameters on the response of the dam are investigated. Subsequently, basic parameters are calibrated based on the initial investigation results, and the effective stress analysis is carried out for the Karun III dam by employing the modified parameters.

Study of Permanent Thermal Insulation for Arch Dam in Cold Region

For virtue of small volume and fast speed of construction, arch dam is the most suitable dam type in cold region, where construction period is relatively short each year. Low average value and large amplitude of atmospheric temperature make temperature stress distribution of arch affect directly by thickness of permanent insulation material as while as the time of thermal insulation. Extreme climate lead to stricter external insulation requirement for cold region arch than these in common district, however, thermal insulation will increase the burden of artificial cooling and extend the construction period. Therefore, it is complicated and critical for arch dam crack prevention to study on permanent thermal insulation. In view of this, finite element method was applied for simulation of construction processes of a practical project in cold region. Influence of permanent thermal insulation layer thickness and selection of insulation time is analyzed, in order to provide basis for permanent thermal insulation optimization.

Effects of TMEM154 haplotypes 1 and 3 on susceptibility to ovine progressive pneumonia virus following natural exposure in sheep1,2,3

Small ruminant lentiviruses (SRLV) adversely affect production and well-being of sheep and goats throughout much of the world. The SRLV, including ovine progressive pneumonia virus (OPPV) in North America, cause lifetime infections, and management procedures to eradicate or reduce disease prevalence are costly. Variants of ovine transmembrane protein 154 gene (TMEM154) affect susceptibility to OPPV. The primary experimental objective was to estimate additive and dominance effects of TMEM154 haplotypes 1 and 3 on susceptibility to OPPV infection following natural exposure. A group of 187 trial lambs was born and raised by mature, infected ewes to ensure natural exposure to OPPV. Parents of trial lambs were heterozygous for haplotypes 1 and 3, producing lambs with diplotypes "1 1," "1 3," and "3 3." A group of 20 sentinel lambs was born and raised by mature, uninfected ewes that were diplotype "1 1." Sentinel lambs had diplotypes "1 1" and "1 3," being sired by the same set of rams as trial lambs. Trial and sentinel lambs were comingled during the experiment. Lambs were weaned at 60 d of age, bled 1 wk after weaning, and thereafter at intervals of 4 or 5 wk until 9 mo of age when OPPV infection status was determined by use of a competitive enzyme-linked immunosorbent assay. Only 1 sentinel lamb became infected. Infection status of trial lambs was analyzed using logistic regression procedures to account for the binary nature of infection status and random effects of sires. Effects of sex, type of birth, type of rearing, age of dam, breed type of dam, and sires were not detected (P>0.20). Infection status was affected by diplotype of lamb (P=0.005), with additive (P=0.002) and dominance (P=0.052) effects identified. Predicted probabilities of infection for lambs with diplotypes "1 1," "1 3," and "3 3" were 0.094, 0.323, and 0.346, respectively. Confidence intervals for probabilities of infection for diplotypes "1 3" and "3 3" were similar, but distinct from diplotype "1 1." These results are consistent with complete dominance of haplotype 3 relative to haplotype 1. The probability of infection at 9 mo of age for lambs with either diplotype "1 3" or "3 3" averaged 3.56 times that of lambs with diplotype "1 1." Genetic susceptibility to OPPV infection can be reduced by selection to increase the frequency of haplotype 1, resulting in a greater proportion of lambs with diplotype "1 1."

Arch Dam Deformation Prediction Model Based on PSO-SVM

Arch dam has gradually evolved as one of dam type as main large-scale hydraulic project, dam deformation prediction is an important part of dam safety monitoring, and it is difficult to forecast because of the complicated nonlinear characteristics of the monitoring data. Support Vector Machine (SVM) could solve the small sample, nonlinear high dimension problem due to the excellent generalization ability, and hence it has been widely used in the forecast of arch dam deformation. However, the forecast results considerably depend on the choice of SVM model parameters. In this paper, Particle Swarm Optimization (PSO), which has the characteristic of fast global optimization, was applied to optimize the parameters in SVM, and then the dam deformation prediction model based on PSO-SVM could be established. The model is applied to a certain arch dam foundation prediction. The accuracy of this employed approach was examined by comparing it with multiple regression method. In a word, the experimental results indicate that the proposed method based on PSO-SVM can be used in arch dam deformation prediction.

Study of Flood Control Capability and Advanced Application of Multiple Dams Constructed in Series

The new concept for flood control called ‘Cascade’ method which permits dams to overflow around an upstream region with a sequence of dams constructed in a river is proposed. Multiple small scale dry dams should be constructed in series instead of a large scale dam in order to prevent flood disaster and preserve the natural environment. Recently a flood control dam with a bottom outlet hole as its regular spillway, known as ‘dry dam’, has been reviewed, planned and built in some sites in Japan. Under a condition of a common reservoir capacity, the Cascade type flood control permitting upstream dams to overflow except for the most downstream dam in a river is compared with a conventional one not to overflow each dam in a numerical simulation. As a result, it is made clear that the Cascade method using multiple dry dams is much more effective than the conventional one. In this connection, the Cascade type flood control method permitting upstream dams to overflow from emergency spillways except for the most downstream dam can be applied to normal storage dams with slide gates operated conventionally. Therefore, it could become an effective adaptation method for the global warming problem since it is performed by only changing how to operate slide gates in existing storage dams constructed in series. In addition, we also propose a new type of dry dam that has a closable and openable gate for its regular spillway primarily to retain the water for the water utilization. The new type of dry dam, which should be constructed in the upper reach away from the existing downstream storage dam needing still more its capacity for water utilization, ensures the amount of water available for the use by closing the regular spillway after the new dry dam is at full capacity, and the flood control capacity of the dams including the new dry dam is stronger than that of the normal dams owing to the storage function with the new dry dam. The new dry dams may improve the water utilization, the flood control, and environmentfriendliness under the current condition in Thailand damaged by the severe flood in 2011.

Effect of Construction Material on Dam Type Selection of the Büyük Karaçay Dam (Hatay, Turkey)

This paper covers the investigation of construction materials and selection of the dam type for the Buyuk Karacay Dam, which was planned to be constructed on Buyuk Karacay River 20 km to the SW of Hatay (Southern Turkey). The purposes of the dam are irrigation, domestic water supply, and producing energy. Auxiliary structures locations have been determined during the study of detailed geological maps of the dam axis and reservoir area. Quality, quantity and hauling distance of natural construction materials were effective to select different dam types. For engineering geological studies exploration boreholes were drilled at the dam site; pressuremeter tests were performed in order to determine bearing capacity and elasticity properties of rocks; pressured water tests were also performed to determine permeability of the dam site. Moreover, physical and mechanical properties of rocks were determined by the laboratory test. In the feasibility stage, the dam type was chosen as the central core rock-fill dam, depending on state of natural construction materials. In design stage dam type was changed as faced symmetrical hardfill dam. Finally, the dam type was revised again during the design stage as concrete face rockfill dam.

Study on Automatic Safety Monitoring and Management System of Tailings Reservoir

The tailings dam is a very important component part in mine production facilities. Meanwhile, it is a potential major risk source with high potential energy. Through collecting many accidents of the tailings dam, it is showed that accident type of the tailings dam mainly is dam-break, damage of drainage system, leakage of tailings, etc. On the basis of this analysis, the main causes of dam-break are slope instability, breaking construction rule, unusual rainfall, etc. The automatic safety monitoring and management system of the tailings reservoir (ASMMS) is a powerful measure for mine safety production. The basic frame of the ASMMS is proposed. The main contents and key problems of the ASMMS are also analyzed. It can provide a strong theoretical and technical basis for the safety and management of the tailings dam.

直列配置された流水型ダム群の洪水制御能力の検討

A new flood control concept called 'Cascade method' which permits a dam to overflow from an emergency spillway around an upstream region with plural dams set in series in a river basin has been suggested. In this study, characteristics of the new flood control method are investigated for various inflow flood hydrographs whose shape is transformed systematically. As a result of this study, it is made clear that the new method can control more effectively for leaning forward inflow hydrographs. In addition, we propose another new type of a dry dam to encourage water-utilization. The new type has an outlet work for flood control with a slide gate which can be closed automatically depending on hydraulic pressure or buoyancy. We call this gate 'pressure gate'. The new type of dry dams constructed in series with a pressure gate strengthens still more flood control capability of the Cascade method.