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Panoramic variation analysis of a family with neurodevelopmental disorders caused by biallelic loss-of-function

《医学前沿(英文)》 doi: 10.1007/s11684-023-1006-x

摘要: Highly clinical and genetic heterogeneity of neurodevelopmental disorders presents a major challenge in clinical genetics and medicine. Panoramic variation analysis is imperative to analyze the disease phenotypes resulting from multilocus genomic variation. Here, a Pakistani family with parental consanguinity was presented, characterized with severe intellectual disability (ID), spastic paraplegia, and deafness. Homozygosity mapping, integrated single nucleotide polymorphism (SNP) array, whole-exome sequencing, and whole-genome sequencing were performed, and homozygous variants in TMEM141 (c.270G>A, p.Trp90*), DDHD2 (c.411+767_c.1249-327del), and LHFPL5 (c.250delC, p.Leu84*) were identified. A Tmem141p.Trp90*/p.Trp90* mouse model was generated. Behavioral studies showed impairments in learning ability and motor coordination. Brain slice electrophysiology and Golgi staining demonstrated deficient synaptic plasticity in hippocampal neurons and abnormal dendritic branching in cerebellar Purkinje cells. Transmission electron microscopy showed abnormal mitochondrial morphology. Furthermore, studies on a human in vitro neuronal model (SH-SY5Y cells) with stable shRNA-mediated knockdown of TMEM141 showed deleterious effect on bioenergetic function, possibly explaining the pathogenesis of replicated phenotypes in the cross-species mouse model. Conclusively, panoramic variation analysis revealed that multilocus genomic variations of TMEM141, DDHD2, and LHFPL5 together caused variable phenotypes in patient. Notably, the biallelic loss-of-function variants of TMEM141 were responsible for syndromic ID.

关键词: neurodevelopmental disorder     autosomal recessive intellectual disability     consanguinity     spastic paraplegia     hearing loss     TMEM141    

Seismic responses and resilience of novel SMA-based self-centring eccentrically braced frames under near-fault ground motions

Zhi-Peng CHEN; Songye ZHU

《结构与土木工程前沿(英文)》 2022年 第16卷 第8期   页码 962-975 doi: 10.1007/s11709-022-0873-6

摘要: In this paper, the seismic responses and resilience of a novel K-type superelastic shape memory alloy (SMA) self-centring (SC) eccentrically braced frame (EBF) are investigated. The simulation models of the SMA-based SC-EBF and a corresponding equal-stiffness traditional EBF counterpart are first established based on some existing tests. Then twenty-four near-fault ground motions are used to examine the seismic responses of both EBFs under design basis earthquake (DBE) and maximum considered earthquake (MCE) levels. Structural fragility and loss analyses are subsequently conducted through incremental dynamic analyses (IDA), and the resilience of the two EBFs are eventually estimated. The resilience assessment basically follows the framework proposed by Federal Emergency and Management Agency (FEMA) with the additional consideration of the maximum residual inter-storey drift ratio (MRIDR). The novel SMA-based SC-EBF shows a much better resilience in the study and represents a promising attractive alternative for future applications.

关键词: shape memory alloy     eccentrically braced frame     self-centring     fragility     loss function     resilience    

鲁棒的极大熵聚类算法RMEC及其例外点标识

邓赵红,王士同,吴锡生,胡德文

《中国工程科学》 2004年 第6卷 第9期   页码 38-45

摘要:

针对极大熵聚类算法MEC(maximum entropy clustering)对例外点(outliers)较敏感和不能标识例外点的缺陷,提出了一种改进的极大熵聚类算法RMEC(robust maximum entropy clustering)。该算法的基本思想是通过引入Vapnik's ε-不敏感损失函数和权重因子重新构建目标函数,并利用优化理论推导出新的学习公式。RMEC算法不但对例外点较之MEC算法有更好的鲁棒性,而且还能有效地利用学习后的权重因子标识出数据集中存在的例外点。仿真试验结果亦表明了RMEC算法的上述优点。

关键词:     聚类     鲁棒性     例外点     ε-不敏感损失函数     权重因子    

Power fluctuation and power loss of wind turbines due to wind shear and tower shadow

Binrong WEN, Sha WEI, Kexiang WEI, Wenxian YANG, Zhike PENG, Fulei CHU

《机械工程前沿(英文)》 2017年 第12卷 第3期   页码 321-332 doi: 10.1007/s11465-017-0434-1

摘要:

The magnitude and stability of power output are two key indices of wind turbines. This study investigates the effects of wind shear and tower shadow on power output in terms of power fluctuation and power loss to estimate the capacity and quality of the power generated by a wind turbine. First, wind speed models, particularly the wind shear model and the tower shadow model, are described in detail. The widely accepted tower shadow model is modified in view of the cone-shaped towers of modern large-scale wind turbines. Power fluctuation and power loss due to wind shear and tower shadow are analyzed by performing theoretical calculations and case analysis within the framework of a modified version of blade element momentum theory. Results indicate that power fluctuation is mainly caused by tower shadow, whereas power loss is primarily induced by wind shear. Under steady wind conditions, power loss can be divided into wind farm loss and rotor loss. Wind farm loss is constant at 3α(3α−1)R2/(8H2). By contrast, rotor loss is strongly influenced by the wind turbine control strategies and wind speed. That is, when the wind speed is measured in a region where a variable-speed controller works, the rotor loss stabilizes around zero, but when the wind speed is measured in a region where the blade pitch controller works, the rotor loss increases as the wind speed intensifies. The results of this study can serve as a reference for accurate power estimation and strategy development to mitigate the fluctuations in aerodynamic loads and power output due to wind shear and tower shadow.

关键词: wind turbine     wind shear     tower shadow     power fluctuation     power loss    

Turnover and loss of nitrogenous compounds during composting of food wastes

YANG Yanmei, ZHANG Xiangfeng, YANG Zhifeng, XI Beidou, LIU Hongliang

《环境科学与工程前沿(英文)》 2008年 第2卷 第2期   页码 251-256 doi: 10.1007/s11783-008-0042-8

摘要: Few people have so far explored into the research of the dynamics of various nitrogenous compounds (including water-soluble nitrogen) in composting of food wastes. This study aimed to investigate the solid-phase nitrogen, water-soluble nitrogen, nitrogen loss together with ammonia volatilization in the process of food wastes composting. A laboratory scale static aerobic reactor in the experiment was employed in the composting process of a synthetic food waste, in which sawdust was used as the litter amendment. In the experiment, oxygen was supplied by continuous forced ventilation for 15 days. The results have shown that the concentrations of total nitrogen and organic nitrogen decrease significantly in the composting process, whereas NH-N concentration increases together with little fluctuation in NO-N. After composting, the total content of the water-soluble nitrogen compounds in the compost greatly increased, the total nitrogen loss amounted to 50% of the initial nitrogen, mainly attributed to ammonia volatilization. 56.7% of the total ammonia volatilization occurred in the middle and late composting of the thermophilic stage. This suggested that the control at the middle and late composting of thermophilic stage is the key to nitrogen loss in the food waste compost.

Winner determination problem with loss-averse buyers in reverse auctions

Xiaohu QIAN, Min HUANG, Yangyang YU, Xingwei WANG

《工程管理前沿(英文)》 2017年 第4卷 第2期   页码 212-220 doi: 10.15302/J-FEM-2017019

摘要: Reverse auctions have been widely adopted for purchasing goods and services. This paper considers a novel winner determination problem in a multiple-object reverse auction in which the buyer involves loss-averse behavior due to uncertain attributes. A corresponding winner determination model based on cumulative prospect theory is proposed. Due to the NP-hard characteristic, a loaded route strategy is proposed to ensure the feasibility of the model. Then, an improved ant colony algorithm that consists of a dynamic transition strategy and a Max-Min pheromone strategy is designed. Numerical experiments are conducted to illustrate the effectiveness of the proposed model and algorithm. We find that under the loaded route strategy, the improved ant colony algorithm performs better than the basic ant colony algorithm. In addition, the proposed model can effectively characterize the buyer’s loss-averse behavior.

关键词: reverse auction     loss aversion     winner determination     improved ant colony algorithm    

A novel energy loss model and optimization design of the coin chute flection curve

Qinghua LIANG, Jinqiu MO, Weizhong GUO

《机械工程前沿(英文)》 2012年 第7卷 第1期   页码 38-46 doi: 10.1007/s11465-012-0311-x

摘要:

In this paper, we propose a novel design model based on the energy loss of the coin (ELM model) to optimize the flection curve, which is widely used in coin operated machines. Two different kinds of energy loss models are analyzed according to dynamic characteristics of the coin falling movement. The flection curve is constructed based on cubic quasi-uniform B-spline with the data points and end points derivatives as inputs, and the curve model is governed and affected by energy loss equations, allowing to minimize the total energy loss before the coin arrives at the detecting position, thus to reduce the energy loss and collisions between the coin and the flection, thus to improve the testing accuracy. A case study with a typical Chinese currency coin shows the effectiveness of the model using GA optimization toolbox.

关键词: flection curve     B-spline     energy loss model (ELM model)     optimization design    

Power system reconfiguration and loss minimization for a distribution systems using “Catfish PSO” algorithm

K Sathish KUMAR,S NAVEEN

《能源前沿(英文)》 2014年 第8卷 第4期   页码 434-442 doi: 10.1007/s11708-014-0313-y

摘要: One of the very important ways to save electrical energy in the distribution system is network reconfiguration for loss reduction. Distribution networks are built as interconnected mesh networks; however, they are arranged to be radial in operation. The distribution feeder reconfiguration is to find a radial operating structure that optimizes network performance while satisfying operating constraints. The change in network configuration is performed by opening sectionalizing (normally closed) and closing tie (normally opened) switches of the network. These switches are changed in such a way that the radial structure of networks is maintained, all of the loads are energized, power loss is reduced, power quality is enhanced, and system security is increased. Distribution feeder reconfiguration is a complex nonlinear combinatorial problem since the status of the switches is non-differentiable. This paper proposes a new evolutionary algorithm (EA) for solving the distribution feeder reconfiguration (DFR) problem for a 33-bus and a 16-bus sample network, which effectively ensures the loss minimization.

关键词: distribution system reconfiguration (DFR)     power loss reduction     catfish particle swarm optimization (catfish PSO)     radial structure    

Effect of mulching with maize straw on water infiltration and soil loss at different initial soil moistures

Yifu ZHANG,Hongwen LI,Jin HE,Qingjie WANG,Ying CHEN,Wanzhi CHEN,Shaochun MA

《农业科学与工程前沿(英文)》 2016年 第3卷 第2期   页码 161-170 doi: 10.15302/J-FASE-2016104

摘要: Mulching and soil water content (SWC) have a significant impact on soil erosion, and this study investigated the effect of straw mulching on water infiltration and soil loss under different initial SWC treatments in a rainfall simulation experiment conducted in northern China. Increasing initial SWC can decrease soil infiltration and increase soil loss. During an 80 mm rainfall event (80 mm·h for 60 min), 8%, 12% and 16% initial SWC treatments decreased cumulative infiltration by 8.7%, 42.5% and 58.1%, and increased total sediment yield by 44, 146 and 315 g, respectively, compared to 4% initial SWC. However, in all the straw mulching treatments, there was no significant difference in stable infiltration rate between the different initial SWC treatments. For all initial SWC treatments, straw mulching of 30% or more significantly enhanced water infiltration by over 31% and reduced soil loss by over 49%, compared to the unmulched treatment. Taking into consideration the performance of no-till planters, a maize straw mulching rate of 30% to 60% (1400–3100 kg·hm ) is recommended for the conservation of water and soil in northern China.

关键词: infiltration     initial soil water content     rainfall simulation     soil loss     straw mulching    

Effects of riparian vegetation patterns on the distribution and potential loss of soil nutrients: a case

Erhui GUO,Liding CHEN,Ranhao SUN,Zhaoming WANG

《环境科学与工程前沿(英文)》 2015年 第9卷 第2期   页码 279-287 doi: 10.1007/s11783-014-0667-8

摘要: A riparian ecosystem is an ecological transition zone between a river channel and terrestrial ecosystems. Riparian ecosystems play a vital role in maintaining stream health and bank stabilization. The types of riparian vegetation have changed greatly because of human activities along the Wenyu River. This study examines the impact of riparian vegetation patterns on water pollution due to soil nutrient loss. Four riparian vegetation patterns from the river channel to the upland were chosen as the focus of this study: grassland, cropland, grassland-cropland, and grassland-manmade lawn. The different distributions of soil nutrients along vegetation patterns and the potential risk of nutrient loss were observed and compared. The results showed that riparian cropland has the lowest value of total nitrogen (TN), total phosphorus (TP), available nitrogen (AN), available phosphorus (AP), and organic matter (OM), but it has the highest soil bulk density (BD). The distributions of soil TN, TP, AN, AP, and OM exhibited a declining trend from the upland toward the river channel for riparian cropland, whereas a different trend was observed for the riparian grassland. The vegetation patterns of grassland-cropland and grassland-manmade lawn show that the grassland in the lower slope has more nutrients and OM but lower soil BD than the cropland or manmade lawn in the upper slope. So, the lower-slope grassland may intercept and infiltrate surface runoff from the upland. The lower-slope grassland has higher levels of soil TN, TP, AN, and AP, and thus it may become a new source of nutrient loss. Our results suggest that the management of the riparian vegetation should be improved, particularly in densely populated areas, to control soil erosion and river pollution.

关键词: riparian     vegetation patterns     soil nutrient distribution     nutrient loss     management    

一种用于淮河上游日径流预测的增强型LSTM模型 Article

满媛媛, 杨勤丽, 邵俊明, 王国庆, 白林龙, 薛运宏

《工程(英文)》 2023年 第24卷 第5期   页码 230-239 doi: 10.1016/j.eng.2021.12.022

摘要:

径流预测对防洪具有重要意义。然而,由于径流过程的复杂性和随机性,很难准确预测日径流量,尤其是洪峰径流量。为此,本研究提出了一种用于日径流预测的增强型长短期记忆(LSTM)模型,其中集成了特征提取器并引入了新的损失函数。具体而言,为每个气象站建立由三个LSTM网络组成的特征提取器,旨在提取每个气象站输入数据的时间特征。此外,两个损失函数[ peak error tanh(PET)、peak error swish(PES)]用来增强峰值径流预测的权重,同时减少正常径流预测的权重。本研究以中国淮河流域上游为研究对象,利用增强型LSTM模型进行1960—2016 年的日径流预测。结果表明,增强型LSTM模型表现良好,纳什效率系数(NSE)在验证期(2005 年11 月至2016 年12 月)达到了0.917~0.924,优于广泛使用的集总式水文模型(AWBM、Sacramento、SimHyd、Tank Model)和数据驱动模型[人工神经网络(ANN)、支持向量回归(SVR)、门控循环单元(GRU)]。以PES 作为损失函数的增强型LSTM在极端径流预测方面表现最佳,在洪水期间的平均NSE为0.873。此外,海拔较高的气象站的降水比距离出水口最近的气象站对径流预测的影响更大。该研究可为流域日径流预测提供有效工具,为流域防洪和水安全管理提供技术支持。

关键词: 径流预测     长短期记忆网络     淮河上游流域     极端径流     损失函数    

Low-carbohydrate diets lead to greater weight loss and better glucose homeostasis than exercise: a randomized

《医学前沿(英文)》 2021年 第15卷 第3期   页码 460-471 doi: 10.1007/s11684-021-0861-6

摘要: Lifestyle interventions, including dietary adjustments and exercise, are important for obesity management. This study enrolled adults with overweight or obesity to explore whether either low-carbohydrate diet (LCD) or exercise is more effective in metabolism improvement. Forty-five eligible subjects were randomly divided into an LCD group (n=22) and an exercise group (EX, n=23). The subjects either adopted LCD (carbohydrate intake<50 g/day) or performed moderate-to-vigorous exercise (≥30 min/day) for 3 weeks. After the interventions, LCD led to a larger weight loss than EX (−3.56±0.37 kg vs. −1.24±0.39 kg, P<0.001), as well as a larger reduction in fat mass (−2.10±0.18 kg vs. −1.25±0.24 kg, P=0.007) and waist circumference (−5.25±0.52 cm vs. −3.45±0.38 cm, P=0.008). Both interventions reduced visceral and subcutaneous fat and improved liver steatosis and insulin resistance. Triglycerides decreased in both two groups, whereas low-density lipoprotein cholesterol increased in the LCD group but decreased in the EX group. Various glycemic parameters, including serum glycated albumin, mean sensor glucose, coefficient of variability (CV), and largest amplitude of glycemic excursions, substantially declined in the LCD group. Only CV slightly decreased after exercise. This pilot study suggested that the effects of LCD and exercise are similar in alleviating liver steatosis and insulin resistance. Compared with exercise, LCD might be more efficient for weight loss and glucose homeostasis in people with obesity.

关键词: low-carbohydrate diet     obesity     nonalcoholic fatty liver disease     continuous glucose monitoring     mean sensor glucose    

A novel approach to minimizing material loss for computer numerical control flank-regrinding of worn

《机械工程前沿(英文)》 2023年 第18卷 第3期 doi: 10.1007/s11465-023-0757-z

摘要: Flanks of end mills are prone to wear in a long machining process. Regrinding is widely used in workshops to restore the flank to an original-like state. However, the traditional method involves material waste by trial and error and dramatically decreases the potential regrinding. Moreover, over-cut would happen to the flutes of worn cutters in the regrinding processes because of improper wheel path. This study presented a new approach to planning the wheel path for regrinding worn end mills to minimize material loss and recover the over-cut. In planning, a scaling method was developed to determine the maximum size of the new cutter according to the similarity of cutter shapes before and after regrinding. Then, the wheel path is first generated by envelope theory to regrind the worn area with a four-axis computer numerical control grinder according to the new size of cutters. Moreover, a second regrinding strategy is applied to recover the flute shape over-cut in the first grinding. Finally, the proposed method is verified by an experiment. Results showed that the proposed approach could save 25% of cutter material compared with the traditional method and ensure at least three regrinding times. This work effectively provides a general regrinding solution for the worn flank with maximum material-saving and regrinding period.

关键词: flank-regrinding     worn end mill     wheel position and orientation     material loss     over-cut    

Mass loss and nutrient dynamics during litter decomposition in response to warming and nitrogen addition

Haiyan REN, Jie QIN, Baolong YAN, Alata, Baoyinhexige, Guodong HAN

《农业科学与工程前沿(英文)》 2018年 第5卷 第1期   页码 64-70 doi: 10.15302/J-FASE-2017194

摘要: Plant litter decomposition has been studied extensively in the context of both warming and increased atmospheric nitrogen deposition. However, the temporal patterns of mass loss and nutrient release in response to warming and nitrogen addition remain unclear. A 2-year decomposition experiment aimed to examine the effects of warming and nitrogen addition on decomposition rate, and nitrogen and phosphorus dynamics. The effects of warming and nitrogen addition on decomposition of litter of , a dominant species in a desert steppe of northern China, were studied. Warming and nitrogen addition significantly enhanced litter mass loss by 10% and 16%, respectively, and moreover promoted nitrogen and phosphorus release from the litter in the first year of decomposition, followed by an immobilization period. The interactive effects of warming and nitrogen addition on mass loss, nitrogen and phosphorus concentrations of litter were also found during the decomposition. This study indicates that warming and nitrogen addition increased litter mass loss through altering litter quality. These findings highlight that interactions between climate change and other global change factors could be highly important in driving decomposition responses.

关键词: climate warming     grassland     litter decomposition     nitrogen deposition     nutrient release    

Hypoxia-induced activity loss of a photo-responsive microtubule inhibitor azobenzene combretastatin A4

Yang An, Chao Chen, Jundong Zhu, Pankaj Dwivedi, Yanjun Zhao, Zheng Wang

《化学科学与工程前沿(英文)》 2020年 第14卷 第5期   页码 880-888 doi: 10.1007/s11705-019-1864-6

摘要: The conformation-dependent activity of azobenzene combretastatin A4 (Azo-CA4) provides a unique approach to reduce the side-effects of chemotherapy, due to the light-triggered conformation transition of its azobenzene moiety. Under hypoxic tumor microenvironment, however, the high expression of azoreductase can reduce azobenzene to aniline. It was postulated that the Azo-CA4 might be degraded under hypoxia, resulting in the decrease of its anti-tumor activity. The aim of this study was to verify such hypothesis in HeLa cells . The quantitative drug concentration analysis shows the ratiometric formation of degradation end-products, confirming the bioreduction of Azo-CA4. The tubulin staining study indicates that Azo-CA4 loses the potency of switching off microtubule dynamics under hypoxia. Furthermore, the cell cycle analysis shows that the ability of Azo-CA4 to induce mitotic arrest is lost at low oxygen content. Therefore, the cytotoxicity of Azo-CA4 is compromised under hypoxia. In contrast, combretastatin A4 as a positive control maintains the potency to inhibit tubulin polymerization and break down the nuclei irrespective of light irradiation and oxygen level. This work highlights the influence of hypoxic tumor microenvironment on the anti-tumor potency of Azo-CA4, which should be considered during the early stage of designing translational Azo-CA4 delivery systems.

关键词: hypoxia     microtubule inhibitor     drug delivery     azo-combretastatin A4     photo-responsive    

标题 作者 时间 类型 操作

Panoramic variation analysis of a family with neurodevelopmental disorders caused by biallelic loss-of-function

期刊论文

Seismic responses and resilience of novel SMA-based self-centring eccentrically braced frames under near-fault ground motions

Zhi-Peng CHEN; Songye ZHU

期刊论文

鲁棒的极大熵聚类算法RMEC及其例外点标识

邓赵红,王士同,吴锡生,胡德文

期刊论文

Power fluctuation and power loss of wind turbines due to wind shear and tower shadow

Binrong WEN, Sha WEI, Kexiang WEI, Wenxian YANG, Zhike PENG, Fulei CHU

期刊论文

Turnover and loss of nitrogenous compounds during composting of food wastes

YANG Yanmei, ZHANG Xiangfeng, YANG Zhifeng, XI Beidou, LIU Hongliang

期刊论文

Winner determination problem with loss-averse buyers in reverse auctions

Xiaohu QIAN, Min HUANG, Yangyang YU, Xingwei WANG

期刊论文

A novel energy loss model and optimization design of the coin chute flection curve

Qinghua LIANG, Jinqiu MO, Weizhong GUO

期刊论文

Power system reconfiguration and loss minimization for a distribution systems using “Catfish PSO” algorithm

K Sathish KUMAR,S NAVEEN

期刊论文

Effect of mulching with maize straw on water infiltration and soil loss at different initial soil moistures

Yifu ZHANG,Hongwen LI,Jin HE,Qingjie WANG,Ying CHEN,Wanzhi CHEN,Shaochun MA

期刊论文

Effects of riparian vegetation patterns on the distribution and potential loss of soil nutrients: a case

Erhui GUO,Liding CHEN,Ranhao SUN,Zhaoming WANG

期刊论文

一种用于淮河上游日径流预测的增强型LSTM模型

满媛媛, 杨勤丽, 邵俊明, 王国庆, 白林龙, 薛运宏

期刊论文

Low-carbohydrate diets lead to greater weight loss and better glucose homeostasis than exercise: a randomized

期刊论文

A novel approach to minimizing material loss for computer numerical control flank-regrinding of worn

期刊论文

Mass loss and nutrient dynamics during litter decomposition in response to warming and nitrogen addition

Haiyan REN, Jie QIN, Baolong YAN, Alata, Baoyinhexige, Guodong HAN

期刊论文

Hypoxia-induced activity loss of a photo-responsive microtubule inhibitor azobenzene combretastatin A4

Yang An, Chao Chen, Jundong Zhu, Pankaj Dwivedi, Yanjun Zhao, Zheng Wang

期刊论文