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Seepage analysis of Upper Gotvand Dam concerning gypsum karstification (2D and 3D approaches)

Jamshid SADREKARIMI, Majid KIYANI, Behnam FAKHRI, Mohammad Javad VAHDATIRAD, Amin BARARI

《结构与土木工程前沿（英文）》 2011年 第5卷 第1期   页码 71-78 doi: 10.1007/s11709-010-0083-5

摘要： Upper Gotvand Dam is constructed on the Karun River at the south west of Iran. In this paper, 2D and 3D models of the dam together with the foundation and abutments were established, and several seepage analyses were carried out. Then, the gypsum veins that are scattered throughout the foundation ground were included in the models, and the seepage pattern, considering the dissolution law of gypsum, was analyzed. It was disclosed that the discharge fluxes obtained from 2D and 3D analyses are not similar, and the discharge flux in 3D model is about four times that of the 2D model. Also, the 3D model locates the phreatic surface somewhat higher than the 2D model. This means that the 2D model estimates lower pore water pressure pattern in comparison with the 3D model. These may be attributed to the fact that with 2D model the lateral components of vectors of seepage velocity are ignored. In the current case, the rate of increase of discharge flux due to dissolution of gypsum veins was obtained to be a third-order function of the aperture width. In spite of the fact that the grout curtain is designed to be about 170 m deep, however, complete dissolve of gypsum will severely increase the discharge flux through the foundation ground.

关键词： Upper Gotvand Dam     seepage analysis     gypsum veins     3D model     discharge flux    

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Approaching the upper boundary of driver-response relationships: identifying factors using a novel framework

《环境科学与工程前沿（英文）》 2023年 第17卷 第6期 doi: 10.1007/s11783-023-1676-2

摘要：

● A novel framework integrating quantile regression with machine learning is proposed.

关键词： Driver-response     Upper boundary of relationship     Interpretable machine learning     Quantile regression     Total phosphorus     Chlorophyll a    

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Optimum design and preliminary experiments of a novel parallel end traction apparatus for upper-limb

《机械工程前沿（英文）》 2021年 第16卷 第4期   页码 726-746 doi: 10.1007/s11465-021-0651-5

摘要： Robot-assisted technology has been increasingly employed in the therapy of post stroke patients to deliver high-quality treatment and alleviate therapists’ burden. This paper introduces a novel parallel end traction apparatus (PETA) to supplement equipment selection. Considering the appearance and performance of the PETA, two types of special five-bar linkage mechanisms are selected as the potential configurations of the actuation execution unit because of their compact arrangement and parallel structure. Kinematic analysis of each mechanism, i.e., position solutions and Jacobian matrix, is carried out. Subsequently, a comparative study between the two mechanisms is conducted. In the established source of nondimensional parameter synthesis, the singularity, maximum continuous workspace, and performance variation trends are analyzed. Based on the evaluation results, the final scheme with determined configuration and corresponding near-optimized nondimensional parameters is obtained. Then, a prototype is constructed. By adding a lockable translational degree of freedom in the vertical direction, the PETA can provide 2D planar exercise and 3D spatial exercise. Finally, a control system is developed for passive exercise mode based on the derived inverse position solution, and preliminary experiments are performed to verify the applicability of the PETA.

关键词： parallel mechanism     upper-limb rehabilitation     singularity and workspace analyses     performance evaluation     optimum design    

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Regeneration of vernacular architecture: new rammed earth houses on the upper reaches of the Yangtze

Jiaping LIU, Rongrong HU, Liu YANG, Runshan WANG,

《能源前沿（英文）》 2010年 第4卷 第1期   页码 93-99 doi: 10.1007/s11708-010-0002-4

摘要： In rural areas of western China, most of the vernacular architectures are made of earth. In the process of urbanization, few residents like to build their houses with earth because the old traditional earth house cannot meet their requirement for higher standard of living. As a result, much more energy will be consumed if industrial building materials are used instead of earth. The regeneration of the traditional earth house, therefore, becomes a challenge in new village construction. This paper briefly describes a project about creating a new prototype of earth house for the migrants along the upper reaches of the Yangtze River to shed light on finding an appropriate approach for regenerating the traditional earth houses with the concept of low-energy housing. It includes an investigation of the traditional earth house and the environment condition of the new settlement, the new house design process, and the quantitative evaluation of the living quality of the new house.

关键词： earth house     low-energy housing     upper reaches of the Yangtze River     passive solar technique    

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Design and preliminary evaluation of an exoskeleton for upper limb resistance training

Tzong-Ming WU, Dar-Zen CHEN

《机械工程前沿（英文）》 2012年 第7卷 第2期   页码 188-198 doi: 10.1007/s11465-012-0327-2

摘要：

Resistance training is a popular form of exercise recommended by national health organizations, such as the American College of Sports Medicine (ACSM) and the American Heart Association (AHA). This form of training is available for most populations. A compact design of upper limb exoskeleton mechanism for home-based resistance training using a spring-loaded upper limb exoskeleton with a three degree-of-freedom shoulder joint and a one degree-of-freedom elbow joint allows a patient or a healthy individual to move the upper limb with multiple joints in different planes. It can continuously increase the resistance by adjusting the spring length to train additional muscle groups and reduce the number of potential injuries to upper limb joints caused by the mass moment of inertia of the training equipment. The aim of this research is to perform a preliminary evaluation of the designed function by adopting an appropriate motion analysis system and experimental design to verify our prototype of the exoskeleton and determine the optimal configuration of the spring-loaded upper limb exoskeleton.

关键词： exoskeleton     free-weight exercise     upper limb     motion analysis    

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EEG controlled neuromuscular electrical stimulation of the upper limb for stroke patients

Hock Guan TAN, Cheng Yap SHEE, Keng He KONG, Cuntai GUAN, Wei Tech ANG

《机械工程前沿（英文）》 2011年 第6卷 第1期   页码 71-81 doi: 10.1007/s11465-011-0207-1

摘要：

This paper describes the Brain Computer Interface (BCI) system and the experiments to allow post-acute (<3 months) stroke patients to use electroencephalogram (EEG) to trigger neuromuscular electrical stimulation (NMES)-assisted extension of the wrist/fingers, which are essential pre-requisites for useful hand function. EEG was recorded while subjects performed motor imagery of their paretic limb, and then analyzed to determine the optimal frequency range within the -rhythm, with the greatest attenuation. Aided by visual feedback, subjects then trained to regulate their -rhythm EEG to operate the BCI to trigger NMES of the wrist/finger. 6 post-acute stroke patients successfully completed the training, with 4 able to learn to control and use the BCI to initiate NMES. This result is consistent with the reported BCI literacy rate of healthy subjects. Thereafter, without the loss of generality, the controller of the NMES is developed and is based on a model of the upper limb muscle (biceps/triceps) groups to determine the intensity of NMES required to flex or extend the forearm by a specific angle. The muscle model is based on a phenomenological approach, with parameters that are easily measured and conveniently implemented.

关键词： brain computer interface     neuromuscular electrical stimulation     stroke     musculoskeletal modeling    

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CFD Simulation of thermal hydraulic characteristics in a typical upper plenum of RPV

Mingjun WANG, Lianfa WANG, Yingjie WANG, Wenxi TIAN, Jian DENG, Guanghui SU, Suizheng QIU

《能源前沿（英文）》 2021年 第15卷 第4期   页码 930-945 doi: 10.1007/s11708-021-0728-1

摘要： A comparative computational fluid dynamics (CFD) study was conducted on the three different types of pressurized water reactor (PWR) upper plenum, named TYPE 1 (support columns (SCs) and control rod guide tubes (CRGTs) with two large windows), TYPE 2 (SCs and CRGTs without windows), and TYPE 3 (two parallel perforated barrel shells and CRGTs). First, three types of upper plenum geometry information were collected, simplified, and adopted into the BORA facility, which is a 1/5 scale system of the four-loop PWR reactor. Then, the geometry, including the upper half core, upper plenum region, and hot legs, was built using the platform. After that, an unsteady calculation to simulate the reactor balance operation at hot full power scenario was performed. Finally, the differences of flowrate distribution at the core outlet and temperature distribution and transverse velocity inside the hot legs with different upper plenum internals were compared. The results suggest that TYPE 1 upper plenum internals cause the largest flowrate difference at the core outlet while TYPE 3 leads to the most even distributed flowrate. The distribution and evolution pattern of the tangential velocity inside hot legs is highly dependent on the upper plenum internals. Two counter-rotating swirls exist inside the TYPE 1 hot leg and only one swirl revolving around the hog leg axis exist inside the TYPE 2 hot leg. For TYPE 3, two swirls like that of TYPE 1 rotating around the hot leg axis significantly increase the temperature homogenization speed. This research provides meaningful guidelines for the future optimization and design of advanced PWR upper plenum internal structures.

关键词： pressurized water reactor (PWR)     upper plenum     internal structures     temperature distribution     computational fluid dynamics (CFD)    

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Long-term dam safety monitoring of Punt dal Gall arch dam in Switzerland

M. WIELAND, G.F. KIRCHEN

《结构与土木工程前沿（英文）》 2012年 第6卷 第1期   页码 76-83 doi: 10.1007/s11709-012-0144-z

摘要： The 130 m high Punt dal Gall dam is located at the Swiss-Italian border in the South-eastern part of Switzerland and was completed in 1969. The dam is founded on highly folded and partially crushed dolomite and limestone formations. A grout curtain with an area of 120,000 m was provided for controlling seepage. For the monitoring of the dam deformations five inverted pendulums were installed in the dam and three in the rock foundation of the right abutment outside of the dam. For a seasonal water level fluctuation in the reservoir of about 60 m the maximum amplitude of the radial displacement is 25 mm, which includes both the effects of the water load and temperature effects. Furthermore a comprehensive geodetic network was established, 57 joint meters were installed and cracks in the crest gallery are monitored by crack meters. There are also thermometers, piezometers and rocmeters. Springs at the left and right banks of the dam are monitored and chemical analyses of the seepage water and springs are performed regularly. The dam is equipped with strong motion instruments and several near-field earthquakes have been recorded in the past. The paper describes the long-term safety monitoring of this 42 years old arch dam. A short description of the Swiss practice in dam safety monitoring and emergency planning is also given.

关键词： dam safety concept     arch dam     dam instrumentation     dam safety monitoring    

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我国高坝建设和科技攻关

陈宗梁

《中国工程科学》 2000年 第2卷 第12期   页码 84-89

摘要：

介绍了我国大坝建设的发展和特点，概括了高坝建设中的地质勘探、坝工技术、泄洪消能、坝基处理和髙边坡处理等方面的科技成果和应用水平，展望了我国高坝发展前景并指出今后高坝科技攻关重点。

关键词： 水力发电     高坝     重力坝     拱坝     碾压混凝土坝     面板堆石坝    

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Features of seismic hazard in large dam projects and strong motion monitoring of large dams

Martin WIELAND,

《结构与土木工程前沿（英文）》 2010年 第4卷 第1期   页码 56-64 doi: 10.1007/s11709-010-0005-6

摘要： Earthquakes can affect large dam projects in many different ways. Usually, design engineers are focussing on ground shaking and neglect the other aspects. The May 12, 2008 Wenchuan earthquake has damaged 1803 dams and reservoirs, and 403 hydropower plants with an installed capacity of 3.3GW. Among these dams were the 132-m-high Shapai RCC arch dam and the 156-m-high Zipingpu concrete face rockfill dam. These recently completed dams are dam types which, up to now, have not experienced strong ground shaking. The widespread mass movements have caused substantial damage to dams and surface powerhouses in Sichuan. The different features of earthquake hazard are presented, i.e., ground shaking, faulting and mass movements. It is proposed to prepare project-specific safety plans for all dams, which consist of a matrix where the possible hazards and the corresponding countermeasures are listed. The earthquake behaviors of the Sefid Rud, Zipingpu and Shapai dams, which, in the past, have experienced strong ground shaking from nearby earthquakes, are discussed. Finally, the need for strong motion instrumentation of large dams is discussed. It is proposed that major dams with large damage potential, dams located in areas of high seismicity, and dams showing signs of abnormal behavior be equipped with strong motion instruments.

关键词： seismic hazard     arch dam     concrete face rockfill dam     strong motion instrumentation     reservoir-triggered seismicity     Wenchuan earthquake    

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Upper bound solution to seismic active earth pressure of submerged backfill subjected to partial drainage

《结构与土木工程前沿（英文）》 2021年 第15卷 第6期   页码 1480-1493 doi: 10.1007/s11709-021-0776-y

摘要： In waterfront geotechnical engineering, seismic and drainage conditions must be considered in the design of retaining structures. This paper proposes a general analytical method to evaluate the seismic active earth pressure on a retaining wall with backfill subjected to partial steady seepage flow under seismic conditions. The method comprises the following steps: i) determination of the total head, ii) upper bound solution of seismic active earth thrust, and iii) deduction for the earth pressure distribution. The determination of total head h(x,z) relies on the Fourier series expansions, and the expressions of the seismic active earth thrust and pressure are derived by using the upper bound theorem. Parametric studies reveal that insufficient drainage and earthquakes are crucial factors that cause unfavorable earth pressure. The numerical results confirm the validity of the total head distribution. Comparisons indicate that the proposed method is consistent with other relevant existing methods in terms of predicting seismic active earth pressure. The method can be applied to the seismic design of waterfront retaining walls.

关键词： seismic active earth pressure     partial seepage flow     pore pressure     anisotropy     upper bound theorem    

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Expression status of GATA3 and mismatch repair proteins in upper tract urothelial carcinoma

Yue Wang, Jinxia Zhang, Yunfan Wang, Shufang Wang, Yu Zhang, Qi Miao, Fei Gao, Huiying He

《医学前沿（英文）》 2019年 第13卷 第6期   页码 730-740 doi: 10.1007/s11684-019-0687-7

摘要： GATA binding protein 3 (GATA3) and mismatch repair (MMR) deficiency contribute to the development of urothelial carcinoma. However, the combined expression of GATA3 and microsatellite instability (MSI) in upper tract urothelial carcinoma (UTUC) and its prognostic value have not been investigated. Here, we immunohistochemically stained GATA3 and MMR proteins in 108 UTUC samples. GATA3 was positive in 74 cases, and its expression was significantly lower than in adjacent benign urothelium ( <0.001). Loss of GATA3 expression was statistically associated with adverse clinicopathologic parameters, such as advanced stage, lymphovascular invasion, neural invasion, lymph node metastasis, and extensive necrosis. Cancer-specific survival (CSS, =0.028) and disease-free survival (DFS, =0.024) were significantly shorter in patients with GATA3 negative tumors than in patients with GATA3 positive tumors. The absence of MMR proteins was observed in 8.3% of the cases, and focal staining was identified in 13.0%. When using “lax criteria” which resulted in counting cases as negative where MMR staining was in fact focally positive (<5%), we found that GATA3 was inversely associated with MSI ( =0.005). Moreover, GATA3 /microsatellite stability (MS) tumors were correlated with advanced pT stage ( <0.001) and poor outcome ( =0.019 for CSS, =0.016 for DFS) compared with GATA3 /MSI ones. The GATA3 /MSI cases had unfavorable clinical outcomes compared with GATA3 /MSI cases ( =0.008 for CSS, =0.023 for DFS). This finding raises a question as to whether GATA3 interacts with MSI through the TGF- signaling pathway and regulates UTUC progression.

关键词： upper tract urothelial carcinoma     GATA binding protein 3     mismatch repair     microsatellite instability     prognosis    

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Key problems and solutions in arch dam heightening

Zuoguang FU, Yunlong HE, Sheng SU

《结构与土木工程前沿（英文）》 2011年 第5卷 第1期   页码 98-104 doi: 10.1007/s11709-010-0004-7

摘要： The dam heightening, which is an effective way to increase reservoir volume, has been paid close attention by engineers. Three problems should be dealt with when an arch dam needs to be heightened: stress state getting worse at dam heel, cracking on new added concrete dam surface, and weak bonding between new added concrete and old dam. Taking Geba arch dam as an example, these problems are examined in details through simulation analysis by the finite element method. The tensile stresses on dam’s surface and joint face that have certain relations to the dam heightening can be controlled by some measures.

关键词： arch dam     heighten     tensile stress     finite element method    

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Influence of soft rock-fill material as dam embankment with central bituminous concrete membrane

Peter TSCHERNUTTER

《结构与土木工程前沿（英文）》 2011年 第5卷 第1期   页码 63-70 doi: 10.1007/s11709-010-0016-3

摘要： This paper demonstrates the difficulties in determining the relevant material parameters for a valuation of the deformation behavior of the up- and downstream dam shell by means of an embankment dam of medium height. Laboratory as well as field tests on solid rock-fill material were performed before the beginning of construction. During the construction the properties of the available rock-fill changed from solid to soft materials. This gave rise to the necessity of adjusting the dam design of the downstream dam shoulder. Several times higher dam settlements as well as significant differential settlements between the up- and downstream dam shell were observed during construction and operation. Apart from this situation, the dam has been operated for nearly 20 years and the behavior of the water barrier has been very good.

关键词： embankment dam     bituminous concrete membrane     rock-fill material properties     deformation behavior    

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Evaluation method of dam behavior during construction and reservoir filling and application to real dams

Yuji KOHGO, Akira TAKAHASHI, Tomokazu SUZUKI,

《结构与土木工程前沿（英文）》 2010年 第4卷 第1期   页码 92-101 doi: 10.1007/s11709-010-0009-2

摘要： In this paper we analyzed a real fill-type dam, named the Minami-Aiki Dam, to verify a numerical consolidation method with an elastoplastic model for unsaturated soils. The validities were conducted by comparing the analyzed and measured values during construction and impounding. The settlements calculated showed good agreement to those observed. Though the changing patterns of the measured and calculated pore water pressures were similar, the amounts of pore water pressures induced by the self-weights of embankment and the dissipation speeds were different. The earth pressures measured at the bottom of the core zone showed good agreement with those calculated. This method is valid for estimating behavior of fill-type dams during construction and impounding.

关键词： fill dam     consolidation analysis     unsaturated geo-materials     impounding     construction    

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标题 作者 时间 类型 操作

Seepage analysis of Upper Gotvand Dam concerning gypsum karstification (2D and 3D approaches)

Jamshid SADREKARIMI, Majid KIYANI, Behnam FAKHRI, Mohammad Javad VAHDATIRAD, Amin BARARI

期刊论文

Approaching the upper boundary of driver-response relationships: identifying factors using a novel framework

期刊论文

Optimum design and preliminary experiments of a novel parallel end traction apparatus for upper-limb

期刊论文

Regeneration of vernacular architecture: new rammed earth houses on the upper reaches of the Yangtze

Jiaping LIU, Rongrong HU, Liu YANG, Runshan WANG,

期刊论文

Design and preliminary evaluation of an exoskeleton for upper limb resistance training

Tzong-Ming WU, Dar-Zen CHEN

期刊论文

EEG controlled neuromuscular electrical stimulation of the upper limb for stroke patients

Hock Guan TAN, Cheng Yap SHEE, Keng He KONG, Cuntai GUAN, Wei Tech ANG

期刊论文

CFD Simulation of thermal hydraulic characteristics in a typical upper plenum of RPV

Mingjun WANG, Lianfa WANG, Yingjie WANG, Wenxi TIAN, Jian DENG, Guanghui SU, Suizheng QIU

期刊论文

Long-term dam safety monitoring of Punt dal Gall arch dam in Switzerland

M. WIELAND, G.F. KIRCHEN

期刊论文

我国高坝建设和科技攻关

陈宗梁

期刊论文

Features of seismic hazard in large dam projects and strong motion monitoring of large dams

Martin WIELAND,

期刊论文

Upper bound solution to seismic active earth pressure of submerged backfill subjected to partial drainage

期刊论文

Expression status of GATA3 and mismatch repair proteins in upper tract urothelial carcinoma

Yue Wang, Jinxia Zhang, Yunfan Wang, Shufang Wang, Yu Zhang, Qi Miao, Fei Gao, Huiying He

期刊论文

Key problems and solutions in arch dam heightening

Zuoguang FU, Yunlong HE, Sheng SU

期刊论文

Influence of soft rock-fill material as dam embankment with central bituminous concrete membrane

Peter TSCHERNUTTER

期刊论文

Evaluation method of dam behavior during construction and reservoir filling and application to real dams

Yuji KOHGO, Akira TAKAHASHI, Tomokazu SUZUKI,

期刊论文