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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)    

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    

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    

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    

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    

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    

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    

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    

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    

川江载货汽车滚装运输贡献的评估与发展政策

许茂增,吴旻

《中国工程科学》 2008年 第10卷 第2期   页码 31-34

摘要:

介绍了川江地区的运输环境,阐述了滚装运输产生的行业背景、发展历程和现 状;提出以经济、社会、运输、节能、废气排放的指标,评价川江载货汽车滚装运输对区域经济 社会发展的贡献,建立了运费节约和能源节约指标的计算模型,并以2005年的统计数据和专 项调查数据为基础进行了实际评价。结果表明,川江载货汽车滚装运输兼具降低社会运输成 本、节能、环保与生态价值,有助于长江流域经济社会的可持续发展;分析了滚装运输发展 的机遇及面临的挑战,提出了促进滚装运输发展的政策和措施。

关键词: 川江     滚装运输     评价指标     计算模型     发展政策    

Serologic study on the outbreak of acute upper respiratory tract infections caused by adenovirus 3

JIANG Lufang, JU Liwen, LIN Yuzun, ZHOU Liandi, YU Shunzhang, JIANG Qingwu, JIANG Renjie

《医学前沿(英文)》 2007年 第1卷 第2期   页码 215-218 doi: 10.1007/s11684-007-0041-3

摘要: From April to June, 2004, an outbreak of acute upper respiratory tract infections (AURTI) occurred in the north area of Jiangsu Province, China. Twenty throat swabs were collected with 13 of them presenting an adenovirus (Ad)-like cytopathogenic effect on HEp-2. These were verified as Ad by the electron microscope, direct immunofluorescence assay and Ad primer-mediated PCR. Moreover, they were identified as adenovirus type 3 (Ad3) by type-specific PCR and sequencing of the amplification products. Subsequent serologic studies were carried out to finally diagnose and document the outbreak. The neutralization test of paired serum of six in nine cases show obviously increased antibodies titers. The positive rate of IgM, IgG and recovery phase neutralization antibodies of the cases were 3.7%, 44.4% and 59.5% respectively while those of the controls were 0%, 8.3% and 33.3% respectively. The values of Chi-Square were 0.510, 0.018 and 0.226 respectively. The concordance between IgG detected by ELISA and neutralization anti bodies detected by the neutralization test was 61.4% and the value of Kappa was 0.070. By the serologic study, we can definitively diagnose that this outbreak of acute respiratory infections was caused by Adenovirus 3.

关键词: Twenty     Adenovirus     cytopathogenic     type-specific     AURTI    

基于非关联流动法则的滑移线场及上限法研究

郑颖人,邓楚键,王敬林

《中国工程科学》 2010年 第12卷 第8期   页码 56-69

摘要:

当前岩土材料的滑移线场理论及上限法中都广泛采用经典塑性理论中的关联流动法则,由此得出应力特征线与速度滑移线一致的结论。而试验得知,岩土材料并不服从关联流动法则,因而应力特征线与速度滑移线不可能重合。文章分析了基于关联流动法则的滑移线场及上限法中存在的问题,根据广义塑性理论推导了基于非关联流动法则的滑移线场及上限法,消除了现行滑移线场理论及上限法理论中的种种矛盾。

关键词: 滑移线场     上限法     关联流动法则     非关联流动法则     广义塑性理论    

Synchronous rectal adenocarcinoma and anal canal adenocarcinoma

GU Jin, YAO Yunfeng, LI Jiyou, LU Aiping, WANG Hongyi

《医学前沿(英文)》 2007年 第1卷 第3期   页码 333-337 doi: 10.1007/s11684-007-0064-9

摘要: It is difficult to distinguish a rectal carcinoma with anal metastases from coexistent synchronous anorectal carcinomas. The therapeutic strategy for rectal and anal carcinoma is so different that it should be clearly identified. Here, we report on the case of a 63-year-old man who presented with an upper-third rectal adenocarcinoma. Five months after resection, he developed an adenocarcinoma in the anal canal. The histological slides of both tumors were reviewed and immunohistochemical studies for cytokeratins (CKs) 7 and 20 were performed. The index tumor demonstrated CK 7 /CK 20+ and the second showed CK7+/CK20+. For this reason, we believe the present case had synchronous adenocarcinomas arising from anal canal and the rectum separately. It is very important to differentiate the anorectal lesions pathologically because of the impact on the therapeutic options available, especially for the lesion arising in the anal canal.

关键词: CK7+/CK20+     resection     different     therapeutic strategy     upper-third    

Modeling limit force capacities of high force to volume lead extrusion dampers

《结构与土木工程前沿(英文)》 2021年 第15卷 第3期   页码 609-622 doi: 10.1007/s11709-021-0724-x

摘要: Lead extrusion dampers are supplemental energy-dissipation devices that are used to mitigate seismic structural damage. Small volumetric sizes and high force capacities define high-force-to-volume (HF2V) devices, which can absorb significant response energy without sacrificial damage. However, the design of such devices for specific force capacities has proven difficult based on the complexities of their internal reaction mechanisms, leading to the adoption of empirical approaches. This study developed upper- and lower-bound force capacity estimates from analytical mechanics based on direct and indirect metal extrusion for guiding design. The derived equations are strictly functions of HF2V device geometric parameters, lead material properties, and extrusion mechanics. The upper-bound estimates from direct and indirect extrusion are denoted as (FUB,1, FUB,2) and (FUB,3, FUB,4), respectively, and the lower-bound estimates are denoted as (FLB, FLB,1) based on the combination of extrusion and friction forces. The proposed models were validated by comparing the predicted bounds to experimental force capacity data from 15 experimental HF2V device tests. The experimental device forces all lie above the lower-bound estimates (FLB, FLB,1) and below the upper-bound estimates (FUB,1, FUB,2, FUB,4). Overall, the (FLB, FUB,2) pair provides wider bounds and the (FLB,1, FUB,4/FUB,1) pair provides narrower bounds. The (FLB,1, FUB,1) pair has a mean lower-bound gap of 36%, meaning the lower bound was 74% of the actual device force on average. The mean upper-bound gap was 33%. The bulge area and cylinder diameter of HF2V devices are key parameters affecting device forces. These relatively tight bounds provide useful mechanics-based predictive design guides for ensuring that device forces are within the targeted design range after manufacturing.

关键词: extrusion     lead dampers     upper and lower bound     analytical modelling     limit force    

Treatment of infant postrenal acute renal failure following obstruction due to upper urinary calculi

Hui-Xia ZHOU MD, Zhi-Chun FENG MD, Hao MENG MD, Xiao-Guang ZHOU MD, Shuang LI BM, Jun WANG MM, Shi-Xi DAI BM,

《医学前沿(英文)》 2010年 第4卷 第1期   页码 127-130 doi: 10.1007/s11684-010-0009-6

摘要: The surgical emergency treatments and curative effects of postrenal acute renal failure following obstruction due to upper urinary calculi in infants were evaluated. Of the 13 infants with postrenal acute renal failure following obstruction due to upper urinary calculi, 11 received retrograded catheterizations of the ureter with semi-rigid ureteroscopy (F 6.8), and two received open ureterolithotomy. The results showed that only one infant had anuresis and continuous reduction of hemoglobin 5h after the open ureterolithotomy and received exploration via excision and peritoneal dialysis, and the remaining 12 patients well recovered in this group. The renal function of all the patients was restored without postoperative complications. It is concluded that the retrograded catheterization of the ureter with ureteroscopy is a minimally invasive, safe and effective therapy for postrenal acute renal failure following obstruction due to upper urinary calculi in infants. For those infants whose urethras are thin and small, the open ureterolithotomy is a suitable method. But patients with bleeding tendency need to be corrected prior to the open ureterotomy to remove obstructions.

关键词: infant     acute renal failure     postrenal     ureteroscopy    

标题 作者 时间 类型 操作

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

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

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

期刊论文

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

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

川江载货汽车滚装运输贡献的评估与发展政策

许茂增,吴旻

期刊论文

Serologic study on the outbreak of acute upper respiratory tract infections caused by adenovirus 3

JIANG Lufang, JU Liwen, LIN Yuzun, ZHOU Liandi, YU Shunzhang, JIANG Qingwu, JIANG Renjie

期刊论文

基于非关联流动法则的滑移线场及上限法研究

郑颖人,邓楚键,王敬林

期刊论文

Synchronous rectal adenocarcinoma and anal canal adenocarcinoma

GU Jin, YAO Yunfeng, LI Jiyou, LU Aiping, WANG Hongyi

期刊论文

Modeling limit force capacities of high force to volume lead extrusion dampers

期刊论文

Treatment of infant postrenal acute renal failure following obstruction due to upper urinary calculi

Hui-Xia ZHOU MD, Zhi-Chun FENG MD, Hao MENG MD, Xiao-Guang ZHOU MD, Shuang LI BM, Jun WANG MM, Shi-Xi DAI BM,

期刊论文