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Model test study for ice force on the bank-head of the lead-navigating bank

SONG An, SUN Jinliang, LU Hai, WANG Yi′an

《结构与土木工程前沿（英文）》 2007年 第1卷 第2期   页码 222-228 doi: 10.1007/s11709-007-0027-x

摘要： To determine the bank-head s ice force of the lead-navigating bank at key position that faces the ice directly of certain water conservancy, ice model test in reduced scale is designed and carried out based on the local situation on the spot and data observed. Preliminary conclusions are got through the analysis of the experimental data such as effect of the ice velocity on the ice force , ratio of components of forces when ice sheet acting on the vertical bank-head, ice force ratio of vertical to 45? incline as well as ratio of level ice force to the vertical ice force when acting on 45? incline. Finally, suggestions on determination of the ice force using formula are given after comparison between the result calculated by the present formula of ice force and the experimental results.

关键词： comparison     lead-navigating bank     vertical bank-head     certain     Preliminary    

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Expression pattern and regulation of head-to-head genes

Xinxing CUI,Chunhong YANG,Li KANG,Guiyu ZHU,Qingqing WEI,Yunliang JIANG

《农业科学与工程前沿（英文）》 2014年 第1卷 第2期   页码 130-136 doi: 10.15302/J-FASE-2014013

摘要： Vacuolar protein sorting 36 (VPS36), a protein primarily known for its role in the Endosomal Sorting Complex Required for Transport pathway, has recently been shown to be linked to chicken reproduction. Previous research showed that is significantly downregulated in sexually mature chicken ovaries compared to immature ones. In this study, using real-time quantitative RT-PCR, we investigated the expression pattern of and its head-to-head gene mRNA in chicken follicles. Small white follicles were found to have significantly higher expression of and mRNA than any other sized follicles ( <0.05). The expression of and mRNA were detected in both granulosa and theca layers of pre-ovulatory follicles, the expression of in theca layers was slightly higher than in granulosa cells. Treatment of small yellow follicles with follicle-stimulating hormone and estradiol resulted in a marked decrease of both and mRNA ( <0.05); however, progesterone, transforming growth factor-β 1 and luteinizing hormone induced no significant changes in and mRNA expression in these follicles. These results indicate that the head-to-head genes of and exhibit similar expression in chicken follicles and are involved in chicken follicle development.

关键词： chicken     Vps36     Ckap2     mRNA     follicle    

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Basic consideration of research strategies for head and neck cancer

null

《医学前沿（英文）》 2012年 第6卷 第4期   页码 339-353 doi: 10.1007/s11684-012-0213-7

摘要：

Head and neck cancer (HNC) consists of a group of malignancies affecting closely related anatomical regions of the upper aerodigestive tract (UADT), including the oral cavity, salivary glands, upper and lower jaw bones and facial skin; the nasal cavity, paranasal sinuses, pharynx, larynx and thyroid gland (although the latter is often excluded and considered as part of endocrine neoplasms). Of these, 90% of HNCs are histologically squamous cell carcinomas originating from the mucosal lining. These malignancies are strongly associated with certain environmental and life-style risk factors, principally tobacco in both smoked and smokeless forms, excessive alcohol consumption, diets poor in antioxidants and essential micronutrients, UV light, chemicals used in certain workplaces, and viruses, principally certain strains of human papillomavirus (HPV) and Epstein-Barr virus (EBV). These cancers are frequently aggressive in their biological behaviour with local invasion and metastasis to lymph nodes in the neck. Since most patients are already at late stages of disease at the time of diagnosis, the desirable practice of early diagnosis (first sign of the malignant lesion at an initial stage ) and early treatment, a critical priority to save lives and retain quality of life, is difficult to implement. Thus, primary prevention has been set as a key goal. This article aims to reinforce the basic knowledge of aetiology, key risk factors related to the development of head and neck cancer, basic features of clinical appearance of this group of cancers, and strategies for prevention and early detection. We also suggest basic research strategies on the basis of current knowledge, which should ultimately lead to the improvement of clinical management.

关键词： clinical management     head and neck cancer     prevention and early detection     research strategies     risk factors    

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Information System Engineering Management from the Perspective of Meta-synthesis Methodology—with the Bank

Hong-feng Chai,Quan Sun

《工程管理前沿（英文）》 2016年 第3卷 第4期   页码 404-413 doi: 10.15302/J-FEM-2016037

摘要： The paper empirically studies the engineering practices of the national currency circulation information system-China Union Pay’s Bankcard Information Exchange System. By integrating the meta-synthesis methodology and the financial information system engineering, the paper proposes basic principles and processes of the giant and complex financial information system engineering management, and further explores its paradigm and toolkit.

关键词： financial information system     meta-synthesis methodology     bank card     information exchange    

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Influence of surface cracking, anchor head profile, and anchor head size on cast-in headed anchors in

《结构与土木工程前沿（英文）》   页码 1163-1187 doi: 10.1007/s11709-023-0987-5

摘要： In this study, the concrete cone capacity, concrete cone angle, and load–displacement response of cast-in headed anchors in geopolymer concrete are explored using numerical analyses. The concrete damaged plasticity (CDP) model in ABAQUS is used to simulate the behavior of concrete substrates. The tensile behavior of anchors in geopolymer concrete is compared with that in normal concrete as well as that predicted by the linear fracture mechanics (LFM) and concrete capacity design (CCD) models. The results show that the capacity of the anchors in geopolymer concrete is 30%–40% lower than that in normal concrete. The results also indicate that the CCD model overestimates the capacity of the anchors in geopolymer concrete, whereas the LFM model provides a much more conservative prediction. The extent of the difference between the predictions by the numerical analysis and those of the above prediction models depends on the effective embedment depth of the anchor and the anchor head size. The influence of concrete surface cracking on the capacity of the anchor is shown to depend on the location of the crack and the effective embedment depth. The influence of the anchor head profile on the tensile capacity of the anchors is found to be insignificant.

关键词： cast-in anchor     concrete cone capacity     geopolymer concrete     head size     surface crack     anchor profile    

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The effect of texture and irrigation on the soil moisture vertical-temporal variability in an urban artificial

Xiaofeng ZHANG,Xu ZHANG,Guanghe LI

《环境科学与工程前沿（英文）》 2015年 第9卷 第2期   页码 269-278 doi: 10.1007/s11783-014-0672-y

摘要： Soil moisture variability in natural landscapes has been widely studied; however, less attention has been paid to its variability in the urban landscapes with respect to the possible influence of texture stratification and irrigation management. Therefore, a case study was carried out in the Beijing Olympic Forest Park to continuously monitor the soil in three typical profiles from 26 April to 11 November 2010. The texture stratification significantly affected the vertical distribution of moisture in the non-irrigated profile where moisture was mostly below field capacity. In the profile where irrigation was sufficient to maintain moisture above field capacity, gravity flow led to increased moisture with depth and thus eliminated the influence of texture. In the non-irrigated sites, the upper layer (above 80 cm) exhibited long-term moisture persistence with the time scale approximating the average rainfall interval. However, a coarse-textured layer weakened the influence of rainfall, and a fine-textured layer weakened the influence of evapotranspiration, both of which resulted in random noise-like moisture series in the deeper layers. At the irrigated site, frequent irrigation neutralized the influence of evapotranspiration in the upper layer (above 60 cm) and overshadowed the influence of rainfall in the deeper layer. As a result, the moisture level in the upper layer also behaved as a random noise-like series; whereas due to deep transpiration, the moisture of the deep layer had a persistence time-scale longer than a month, consistent with characteristic time-scales found for deep transpiration.

关键词： moisture vertical distribution     moisture temporal variation     texture stratification     irrigation     meteorological forcing     urban landscape    

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长江干流水下岸坡侵蚀自动识别 Article

颜阁, 程和琴, 姜泽宇, 滕立志, 唐明, 石天, 姜月华, 杨国强, 周权平

《工程（英文）》 2022年 第19卷 第12期   页码 50-61 doi: 10.1016/j.eng.2021.03.027

摘要：

识别河岸侵蚀的风险是确保早期预警和预防或控制包括长江在内的河流集水区崩岸的一项重要挑战。本文引入一种基于地貌要素的算法，通过调整多波束回波探测数据的平坦度来提取河岸侵蚀信息。该算法绘制了10 个水下地貌形态要素，包括坡、坡脚、水平面、脊、顶、谷、凹陷、凸起、坑和坡肩。利用21 个平坦度值构建水下河岸侵蚀特征的识别策略。结果表明：当平坦度为10°时，作为侵蚀载体的岸坡陡坎被坡要素覆盖。平坦度为0°时，冲刷坑和河岸破损由河岸附近的坑要素和岸坡中的凹陷表示。河道水下沙波是加速河岸侵蚀的重要因素，尤其是靠近河岸坡脚的沙波；沙波的临界平坦度为3°。分析了水下地貌形
态要素的分布，并用于绘制河岸侵蚀库存图。分析结果表明，近岸区水深较大，易形成较大的冲刷坑和较长的河岸陡坎。窝崩往往发生在较长的岸坡处，以缩短其长度。经讨论陆地、海洋和河流环境中平坦度值的不同设置，得出的结论是，多样化的平坦度值能够显著识别河流水下地貌形态。因此，本研究为基于平坦度的河流水下地貌形态要素识别提供参考，增强了从大量多波束测深数据定位水下岸坡失稳迹象与风险的能力。

关键词： 多波束测深数据     形态要素     河岸侵蚀     水下陡坎     冲刷坑     崩岸    

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factors for ventilator-associated pneumonia among patients undergoing major oncological surgery for head

null

《医学前沿（英文）》 2017年 第11卷 第2期   页码 239-246 doi: 10.1007/s11684-017-0509-8

摘要：

Patients undergoing major oncological surgery for head and neck cancer (SHNC) have a particularly high risk of nosocomial infections. We aimed to identify risk factors for ventilator-associated pneumonia (VAP) in patients undergoing SHNC. The study included 465 patients who underwent SHNC between June 2011 and June 2014. The rate of VAP, risk factors for VAP, and biological aspects of VAP were retrospectively evaluated. The incidence of VAP was 19.6% (n=95) in patients who required more than 48 h of mechanical ventilation. Staphylococcus (37.7%), Enterobacteriaceae (32.1%), Pseudomonas(20.8%), and Haemophilus (16.9%) were the major bacterial species that caused VAP. The independent risk factors for VAP were advanced age, current smoking status, chronic obstructive pulmonary disease, and a higher simplified acute physiology score system II upon admission. Tracheostomy was an independent protective factor for VAP. The median length of stay in the ICU for patients who did or did not develop VAP was 8.0 and 6.5 days, respectively (P=0.006). Mortality among patients who did or did not develop VAP was 16.8% and 8.4%, respectively (P<0.001). The potential economic impact of VAP was high because of the significantly extended duration of ventilation. A predictive regression model was developed with a sensitivity of 95.3% and a specificity of 69.4%. VAP is common in patients who are undergoing SHNC and who require more than 48 h of mechanical ventilation. Therefore, innovative preventive measures should be developed and applied in this high-risk population.

关键词： ventilator-associated pneumonia (VAP)     pneumonia     risk factors     surgery for head and neck cancer (SHNC)    

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Reliability analysis of the control system of large-scale vertical mixing equipment

YANG Mingjin, LI Xiwen, LI Shaoping, YANG Shuzi

《机械工程前沿（英文）》 2008年 第3卷 第2期   页码 133-138 doi: 10.1007/s11465-008-0037-y

摘要： The control system of vertical mixing equipment is a concentrate distributed monitoring system (CDMS). A reliability analysis model was built and its analysis was conducted based on reliability modeling theories such as the graph theory, Markov process, and redundancy theory. Analysis and operational results show that the control system can meet all technical requirements for high energy composite solid propellant manufacturing. The reliability performance of the control system can be considerably improved by adopting a control strategy combined with the hot spared redundancy of the primary system and the cold spared redundancy of the emergent one. The reliability performance of the control system can be also improved by adopting the redundancy strategy or improving the quality of each component and cable of the system.

关键词： composite     redundancy     monitoring     vertical     technical    

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Biologically inspired model of path integration based on head direction cells and grid cells

Yang ZHOU,De-wei WU

《信息与电子工程前沿（英文）》 2016年 第17卷 第5期   页码 435-448 doi: 10.1631/FITEE.1500364

摘要： Some neurons in the brain of freely moving rodents show special firing pattern. The firing of head direction cells (HDCs) and grid cells (GCs) is related to the moving direction and distance, respectively. Thus, it is considered that these cells play an important role in the rodents’ path integration. To provide a bionic approach for the vehicle to achieve path integration, we present a biologically inspired model of path integration based on the firing characteristics of HDCs and GCs. The detailed implementation process of this model is discussed. Besides, the proposed model is realized by simulation, and the path integration performance is analyzed under different conditions. Simulations validate that the proposed model is effective and stable.

关键词： Head direction cells (HDCs)     Grid cells (GCs)     Path integration     Bionic navigation    

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Performance of vertical axis water turbine with eye-shaped baffle for pico hydropower

Zhuohuan HU, Dongcheng WANG, Wei LU, Jian CHEN, Yuwen ZHANG

《能源前沿（英文）》 2022年 第16卷 第4期   页码 683-696 doi: 10.1007/s11708-020-0689-9

摘要： A series of inline pico hydropower systems, which could be used in confined space, especially for water distribution networks (WDNs), was designed and investigated. The turbine with an eye-shaped vertical water baffle was developed to evaluate the hydraulic performance. A three-dimensional dynamic mesh was employed and the inlet velocity was considered as the inlet boundary condition, whereas the outlet boundary was set as the outflow. Then, numerical simulations were conducted and the standard turbulence model was found to be the best capable of predicting flow features through the comparison with the experimental results. The effects of the opening diameter of the water baffle and installation angle of the rotor on the flow field in the turbine were investigated. The results suggested that the water baffle opening at = 30 mm and the rotor at a 52° angle could achieve the highest efficiency of 5.93%. The proper eye-shaped baffle not only accelerates the fluid flow and generates positive hydrodynamic torque, but also eliminates the flow separation. The scheme proposed in this paper can be exploited for practical applications in the water pipelines at various conditions and power requirements.

关键词： vertical axis water turbine     eye-shaped     vertical water baffle     pico hydropower    

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Effect of undercut on the lower bound stability of vertical rock escarpment using finite element and

Shuvankar DAS; Debarghya CHAKRABORTY

《结构与土木工程前沿（英文）》 2022年 第16卷 第8期   页码 1040-1055 doi: 10.1007/s11709-022-0841-1

摘要： In the present study, the stability of a vertical rock escarpment is determined by considering the influence of undercut. Lower bound finite element limit analysis in association with Power Cone Programming (PCP) is applied to incorporate the failure of rock mass with the help of the Generalized Hoek-Brown yield criterion. The change in stability due to the presence of undercut is expressed in terms of a non-dimensional stability number (σci/γH). The variations of the magnitude of σci/γH are presented as design charts by considering the different magnitudes of undercut offset (H/vu and wu/vu) from the vertical edge and different magnitudes of Hoek-Brown rock mass strength parameters (Geological Strength Index (GSI), rock parameter (mi,), Disturbance factor (D)). The obtained results indicate that undercut can cause a severe stability problem in rock mass having poor strength. With the help of regression analysis of the computed results, a simplified design equation is proposed for obtaining σci/γH. By performing sensitivity analysis for an undisturbed vertical rock escarpment, we have found that the undercut height ratio (H/vu) is the most sensitive parameter followed by GSI, undercut shape ratio (wu/vu), and mi. The developed design equation as well as design charts can be useful for practicing engineers to determine the stability of the vertical rock escarpment in the presence of undercut. Failure patterns are also presented to understand type of failure and extent of plastic state during collapse.

关键词： undercut     vertical escarpment     stability     Hoek-Brown yield criterion     PCP    

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Ultramicrostructure and clinical implications of satellite foci in front of the head of pterygium

LIU Haixia, XIANG Nan, ZHOU Xiongwu, HU Weikun, LI Guigang, ZHANG Hong

《医学前沿（英文）》 2007年 第1卷 第2期   页码 211-214 doi: 10.1007/s11684-007-0040-4

摘要： In our previous studies, grey satellite foci were found in the front of heads of pterygia. This research was designed to investigate the ultramicrostructure and clinical implications of these satellite foci. The satellite foci were observed and counted under slit lamp biomicroscope. The patients with eye pterygia were divided into groups in terms of occupation, sex, age, length of history, grade of congestion, and size of the heads. The SPSS 13.0 software was used for statistical analysis. The cap areas and satellite foci were ultramicrostructurally examined. Among the total 62 eyes with pterygium, satellite foci were found in 34. The overall incidence of satellite foci was 54.8%. There were no significant differences in incidence among the subjects of different sex, age, and length of history. There were significant differences in incidence among the patients of different occupation, grades of congestion, and size of heads. Higher grades of congestion, outdoor occupations and larger pterygium heads were associated with higher incidence of satellite foci. High grades of congestion and bigger heads were also correlated with the number of satellite foci. Length of history bore no correlation with number of satellite foci. Histologically, the components of the cap areas and the foci were identical, with both consisting of mass of active fibroblasts. The activated fibroblasts existed in the natural tissue planes between Bowman s layer and basal cell layer. The fibroblasts in the satellite foci and the cap areas of a pterygium show some features of tumor cells and may play a vital role in the development and progression of a pterygium. The presence and amount of satellite foci around a pterygium can be used as an indicator for the speed of its growth.
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Transversal tube pitch effects on local heat transfer characteristics of the flat tube bank fin mounted

Liangbi WANG, Zhimin LIN, Kangjie SUN, Yuanxin DONG, Song LIU, Yongheng ZHANG,

《能源前沿（英文）》 2010年 第4卷 第3期   页码 333-345 doi: 10.1007/s11708-009-0061-6

摘要： The tube bank fin is commonly used to increase the area of the heat transfer surface with a small heat transfer coefficient of a heat exchanger. If vortex generators (VGs) are punched on the fin surface, the heat transfer performance of the fin can be improved. This paper focused on the effect of transversal tube pitch on the local heat transfer performance of the three-row flat tube bank fin mounted with VGs. On the fin surface, constructing the flow channel but without mounted VGs, the transversal tube pitch was greater, and the span averaged Nusselt number downstream was larger because fewer interactions of vortices would be generated from different VGs located upstream. When the area goodness factor was used as the criteria on the condition of one tube unit of heat exchanger for commonly used fin materials and fin thickness, the transversal tube pitch has considerable effect on the heat transfer enhancement of VGs. Large transversal tube pitch is more sensitive to fin material than to fin thickness.

关键词： heat transfer enhancement     vortex generator     finned flat tube bank     heat exchanger    

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Corporate governance impact on banking risk

Mahdi JEMMALI, Bassem SALHI

《工程管理前沿（英文）》 2020年 第7卷 第2期   页码 182-195 doi: 10.1007/s42524-019-0034-3

摘要： This study aims to determine the relationship between several factors of governance and the level of risk in 10 Tunisian banks during an analysis period of eight years. We propose an important empirical question and examine the internal mechanisms of governance aimed at reducing financial risks. This estimation is based on a model with a single equation that examines variables relative to governance and credit risk to determine their impact on banking financials. Results demonstrate that the internal mechanisms of governance present diverging effects on the financial risk of the Tunisian banks in our case study (i.e., credit risk). Moreover, making applications work by putting together a process and model for banking risk is important. This model can be applied in any bank, and the results can be used to make decisions in real time.

关键词： bank governance     banking risk     process decision     modeling     architecture    

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标题 作者 时间 类型 操作

Model test study for ice force on the bank-head of the lead-navigating bank

SONG An, SUN Jinliang, LU Hai, WANG Yi′an

期刊论文

Expression pattern and regulation of head-to-head genes

Xinxing CUI,Chunhong YANG,Li KANG,Guiyu ZHU,Qingqing WEI,Yunliang JIANG

期刊论文

Basic consideration of research strategies for head and neck cancer

null

期刊论文

Information System Engineering Management from the Perspective of Meta-synthesis Methodology—with the Bank

Hong-feng Chai,Quan Sun

期刊论文

Influence of surface cracking, anchor head profile, and anchor head size on cast-in headed anchors in

期刊论文

The effect of texture and irrigation on the soil moisture vertical-temporal variability in an urban artificial

Xiaofeng ZHANG,Xu ZHANG,Guanghe LI

期刊论文

长江干流水下岸坡侵蚀自动识别

颜阁, 程和琴, 姜泽宇, 滕立志, 唐明, 石天, 姜月华, 杨国强, 周权平

期刊论文

factors for ventilator-associated pneumonia among patients undergoing major oncological surgery for head

null

期刊论文

Reliability analysis of the control system of large-scale vertical mixing equipment

YANG Mingjin, LI Xiwen, LI Shaoping, YANG Shuzi

期刊论文

Biologically inspired model of path integration based on head direction cells and grid cells

Yang ZHOU,De-wei WU

期刊论文

Performance of vertical axis water turbine with eye-shaped baffle for pico hydropower

Zhuohuan HU, Dongcheng WANG, Wei LU, Jian CHEN, Yuwen ZHANG

期刊论文

Effect of undercut on the lower bound stability of vertical rock escarpment using finite element and

Shuvankar DAS; Debarghya CHAKRABORTY

期刊论文

Ultramicrostructure and clinical implications of satellite foci in front of the head of pterygium

LIU Haixia, XIANG Nan, ZHOU Xiongwu, HU Weikun, LI Guigang, ZHANG Hong

期刊论文

Transversal tube pitch effects on local heat transfer characteristics of the flat tube bank fin mounted

Liangbi WANG, Zhimin LIN, Kangjie SUN, Yuanxin DONG, Song LIU, Yongheng ZHANG,

期刊论文

Corporate governance impact on banking risk

Mahdi JEMMALI, Bassem SALHI

期刊论文