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BFT 1

Cu(Inx 1

Doherty功率放大器；输出功率回退；输出阻抗；网络相位 1

Ga1–x)Se2 1

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串并联谐振变换器；全桥；半桥；变频；移相；宽范围输入电压 1

产品设计；知识推送；适用概率匹配；多维情境；个性化 1

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High-order moment methods for LRFD including random variables with unknown probability distributions

Zhao-Hui LU, Yan-Gang ZHAO, Zhi-Wu YU

《结构与土木工程前沿（英文）》 2013年第7卷第3期页码 288-295 doi: 10.1007/s11709-013-0210-1

摘要： The reliability-based load and resistance factors design (LRFD) has been widely used in the structural design codes. In almost all of the current reliability methods for the determination of the load and resistance factors, the basic random variables are assumed to have known probability distributions. However, in reality, the probability distributions of some of the basic random variables are often unknown due to the lack of statistical data. In this paper, the high-order moment methods for LRFD including random variables with unknown probability distributions are proposed. From the investigation of the present paper, it can be concluded that: 1) The load and resistance factors can be determined even when the probability distributions of the basic random variables are unknown; 2) The present method is convenient and more effective in estimating the load and resistance factors in practical engineering since it needs neither the iterative computation of derivatives nor any design points; 3) In the applicable range of the high-order moment method, although the load and resistance factors obtained by the proposed method may be different from those obtained by first order reliability method (FORM), the target mean resistances obtained by both methods are essentially the same.

关键词： high-order moment methods applicable range load and resistance factors target mean resistance

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Range of ecological impact of highway construction in the Longitudinal Range-Gorge Region, China

Jie LIU, Fan CHEN, Haiqing GENG, Xinxin QIU, Binbin CAI,

《环境科学与工程前沿（英文）》 2010年第4卷第3期页码 349-360 doi: 10.1007/s11783-010-0027-2

摘要： The major features of different road sections were identified. Methods quantitatively determining the ecological impact of highway construction were discussed, and a demonstration was presented. The Dabao highway (from Dali to Baoshan) and the Sixiao highway (from Simao to Xiaomengyang) passing through the Longitudinal Range-Gorge Region were used as examples in this paper. For the normal road sections having no important species to protect, a method of ecosystem health assessment was introduced to calculate the overall range of the ecological impact of highway construction. For the road sections having plants or soils of interest, indexes were selected and the range of impact was determined using mathematical methods such as regression analysis and variance analysis. The range of impact on animal populations was also discussed in terms of the minimum living areas required by animal populations and the fragmentation caused by highway construction. The results indicate that the zones impacted by highway construction were composed of both regular and anomalous figures, the range of impacts for different landforms of the two sample highways were substantially different; highway construction had dramatic effects on roadside ecosystem health; the impact on soil factors of farmland was greater than 200 m, and the distance may exceed 1000 m when important large animals were considered.

关键词： range of impact quantitative analysis highway construction Longitudinal Range-Gorge Region

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导航卫星双向伪距时间同步

谭述森

《中国工程科学》 2006年第8卷第12期页码 70-74

摘要：

针对卫星导航系统时间同步需求，提出了导航卫星双向伪距时间同步的理论根据，并就4种基本同步方法（双向无线电伪距同步方法, 星地双向激光伪距同步方法,双向卫星中继无线电伪距同步方法, 双向地球站中继无线电伪距同步方法）与应用进行了分析，与目前国际导航卫星时间同步通用方法相比,具有精度高, 方法简单，设备负担轻特点。

关键词：导航卫星伪距时间同步

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Applying the multi-zone model in predicting the operating range of HCCI engines

Ming JIA, Maozhao XIE, Zhijun PENG,

《能源前沿（英文）》 2010年第4卷第3期页码 414-423 doi: 10.1007/s11708-010-0108-8

摘要： In this paper, a multi-zone model is developed to predict the operating range of homogeneous charge compression ignition (HCCI) engines. The boundaries of the operating range were determined by knock (presented by ringing intensity), partial burn (presented by combustion efficiency), and cycle-to-cycle variations (presented by the sensitivity of indicated mean effective pressure to initial temperature). By simulating an HCCI engine fueled with iso-octane, the knock and cycle-to-cycle variations predicted by the model showed satisfactory agreement with measurements made under different initial temperatures and equivalence ratios; the operating range was also well reproduced by the model. Furthermore, the model was applied to predict the operating range of the HCCI engine under different engine speeds by varying the intake temperatures and equivalence ratios. The potential to extend the operating range of the HCCI engine through two strategies, i.e., variable compression ratio and intake pressure boosting, was then investigated. Results indicate that the ignition point can be efficiently controlled by varying the compression ratio. A low load range can be extended by increasing the intake temperature while reducing the compression ratio. Higher intake temperatures and lower compression ratios can also extend the high load range. Boosting intake pressure is helpful in controlling the combustion of the HCCI engine, resulting in an extended high load range.

关键词： homogeneous charge compression ignition (HCCI) engine multi-zone operating range

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Accelerated degradation of orange G over a widepH range in the presence of FeVO

Xiaoxia Ou, Jianfang Yan, Fengjie Zhang, Chunhua Zhang

《环境科学与工程前沿（英文）》 2018年第12卷第1期 doi: 10.1007/s11783-018-1013-3

摘要： In this study, FeVO was prepared andused as Fenton-like catalyst to degrade orange G (OG) dye. The removalof OG in an aqueous solution containing 0.5 g·L FeVO and 15 mmol·L hydrogen peroxide at pH 7.0 reached 93.2%. Similar rates were achievedat pH 5.7 ( = 0.0471 min ), pH 7.0 ( = 0.0438 min ), and pH 7.7 ( = 0.0434 min ). The FeVO catalyst successfullyovercomes the problem faced in the heterogeneous Fenton process, i.e.,the narrow working pH range. The data for the removal of OG in FeVO systems containing H O conform to the Langmuir–Hinshelwood model ( = 0.9988),indicating that adsorption and surface reaction are the two basicmechanisms for OG removal in the FeVO –H O system. Furthermore, the irradiationof FeVO by visible light significantly increasesthe degradation rate of OG, which is attributed to the enhanced ratesof the iron cycles and vanadium cycles.

关键词： Azo dye Degradation FeVO₄ Kinetics Advanced oxidation processes

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Are Relational Contracting Approaches Applicable to Public Projects in China?

Wei-ya Hao,Hui-ping Ding,Yong-jian Ke,Ying-ying Wang

《工程管理前沿（英文）》 2014年第1卷第4期页码 358-363 doi: 10.15302/J-FEM-2014052

摘要： Rising complexities in construction projects management has boosted the importance of relational contracting (RC) in the field. RC is based on recognition of mutual benefits and win-win scenarios gained through more cooperative relationships between contracting parties. There have been a range of RC initiatives across many countries towards deeper collaborative relationships; however, such formal RC approaches are not yet well established in China. In this paper, the feasibility of implementing RC in the China’s public construction projects is investigated. The results indicate that RC is highly feasible for implementation in China due to its theoretical benefits, its alignment to Chinese culture, and its behaviors in past public construction projects. Three strategies for facilitating the implementation of RC in China are proposed.

关键词： relational contracting public construction relationship

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Kd-tree and quad-tree decompositions for declustering of 2D range queries over uncertain space

Ahmet SAYAR,Süleyman EKEN,Okan ÖZTÜRK

《信息与电子工程前沿（英文）》 2015年第16卷第2期页码 98-108 doi: 10.1631/FITEE.1400165

摘要： We present a study to show the possibility of using two well-known space partitioning and indexing techniques, kd trees and quad trees, in declustering applications to increase input/output (I/O) parallelization and reduce spatial data processing times. This parallelization enables time-consuming computational geometry algorithms to be applied efficiently to big spatial data rendering and querying. The key challenge is how to balance the spatial processing load across a large number of worker nodes, given significant performance heterogeneity in nodes and processing skews in the workload.

关键词： Kd tree Quad tree Space partitioning Spatial indexing Range queries Query optimization

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Efficient regeneration system applicable to five

Juhua LIU,Peiguang SUN,Jing ZHANG,Jiashui WANG,Jianbin ZHANG,Jingyi WANG,Caihong JIA,Pengzhao GAO,Biyu XU,Zhiqiang JIN

《农业科学与工程前沿（英文）》 2016年第3卷第4期页码 330-334 doi: 10.15302/J-FASE-2016118

摘要： Banana ( spp.) is an important staple food, economic crop, and nutritional fruit worldwide. Hybridization is seriously hampered by the long generation time, polyploidy, and sterility of most cultivars. Establishment of an efficient regeneration and transformation system for banana is critical for their genetic improvement. An efficient and reproducible transformation system for banana using direct organogenesis was developed. Media containing benzylaminopurine (BA) combined with one of four other growth regulators was evaluated for the regeneration efficiency of five cultivars and the ability to induce/support development of new banana shoots. The result indicated that the greatest number of shoots per explant for all five cultivars was obtained using MS medium supplemented with 8.9 mmol·L BA and 9.1 mmol·L thidiazuron (TDZ). In 240–270 d, one immature male flower could regenerate between 380 and 456, 310–372, 200–240, 130–156, and 100–130 well-developed shoots for Gongjiao, Red banana, Rose banana, Baxi, and Xinglongnaijiao, respectively. Such a system will facilitate molecular breeding and functional genomics of banana.

关键词： banana (Musa spp) system regeneration

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近程毫米波合成孔径辐射计被动测距原理

王本庆,李兴国

《中国工程科学》 2010年第12卷第3期页码 95-99

摘要：

毫米波合成孔径技术利用了物体自身辐射电磁波的相位信息，采用很少阵元就能实现实时成像，但目前合成孔径技术只是限于亮温成像，缺少了目标的距离信息，这对于目标探测与识别很不利。提出在近程条件下合成孔径被动测距原理和相应的双正交傅立叶变换算法，并给出了近程距离分辨率公式，近程成像的特点是成像公式中存在二次相位因子，而且距离分辨率和距离的平方成反比。毫米波合成孔径被动成像可以同时得到物体辐射的亮温分布和距离分布，能够有效克服离焦引起的图像模糊，对图像的反降晰和目标识别具有重要意义。

关键词：毫米波辐射计合成孔径近程成像被动测距 BFT

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An experimental study for optimization of high range water reducing superplasticizer in self compacting

Rahul DUBEY, Pardeep KUMAR

《结构与土木工程前沿（英文）》 2013年第7卷第1期页码 62-71 doi: 10.1007/s11709-013-0192-z

摘要： Concrete is extensively used construction material in the infrastructure development industry. With increase in technical knowhow, the need of research for high performance concretes such as self-compacting concrete (SCC) has increased in the last decade. The adaptability of SCC is due to its fluidic behavior in fresh state. However, to develop SCC using indigenous materials, the lack of standardized mix design procedures is the biggest impediment. Although with the advent of chemical admixtures, it is possible to achieve concrete with high fluidity, but at the same time durability issues require more attention. To have these fresh state properties SCC mixes are typically designed with high powder contents, and chemical admixtures. Proportioning and optimization of these materials is a key issue in the mix design of SCC. This paper focuses mainly on experimental study to optimize dosages of superplasticizer for mortar of SCC and then in concrete mixture itself.

关键词： self-compacting concrete (SCC) fresh properties superplasticizer optimization compressive strength

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Mechatronic design of a novel linear compliant positioning stage with large travel range and high out-of-plane

Hua LIU, Xin XIE, Ruoyu TAN, Lianchao ZHANG, Dapeng FAN

《机械工程前沿（英文）》 2017年第12卷第2期页码 265-278 doi: 10.1007/s11465-017-0453-y

摘要：

Most of the XY positioning stages proposed in previous studies are mainly designed by considering only a single performance indicator of the stage. As a result, the other performance indicators are relatively weak. In this study, a 2-degree-of-freedom linear compliant positioning stage (LCPS) is developed by mechatronic design to balance the interacting performance indicators and realize the desired positioning stage. The key parameters and the coupling of the structure and actuators are completely considered in the design. The LCPS consists of four voice coil motors (VCMs), which are conformally designed for compactness, and six spatial leaf spring parallelograms. These parallelograms are serially connected for a large travel range and a high out-of-plane payload capacity. The mechatronic model is established by matrix structural analysis for structural modeling and by Kirchhoff’s law for the VCMs. The sensitivities of the key parameters are analyzed, and the design parameters are subsequently determined. The analytical model of the stage is confirmed by experiments. The stage has a travel range of 4.4 mm× 7.0 mm and a 0.16% area ratio of workspace to the outer dimension of the stage. The values of these performance indicators are greater than those of any existing stage reported in the literature. The closed-loop bandwidth is 9.5 Hz in both working directions. The stage can track a circular trajectory with a radius of 1.5 mm, with 40 mm error and a resolution of lower than 3 mm. The results of payload tests indicate that the stage has at least 20 kg out-of-plane payload capacity.

关键词： mechatronic design linear compliant positioning stage large travel range high out-of-plane payload capacity spatial parallelogram voice coil motor sensitivity analysis

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A novel cataplasma matrix of traditional Chinese medicine

Jing TIAN, Xiaolei ZHANG, Xueqin ZHOU,

《化学科学与工程前沿（英文）》 2010年第4卷第1期页码 91-95 doi: 10.1007/s11705-009-0304-4

摘要： The aim of this paper was to develop a cataplasma matrix that can be applicable to both watersoluble and liposoluble drugs. The gellan gum and konjaku were employed as the scaffold materials of the matrix. With polyacrylic acid sodium and oligosaccharides as tacktifier, the formula of the cataplasma matrix was optimized in the orthogonal method as: gellan gum 0.4 g, xanthan€gum 0.03 g, konjac glue 0.1 g, glycerin 4 g, Gluco-Adhesive T (GAT) 6 g, Gluco-Adhesive E (GAE) 6 g, polyacrylic acid sodium 0.22 g, and sorbitol 3 g. The 180° peel strength, the tensile strength and the elongation at break was 3.043 N, 0.275 MPa and 91.05%, respectively. Furthermore, the drug-compatibilities of the matrix were investigated with baicalin, berberine and curcumin, which were used as the models of hydrophilic, poor-water-soluble and hydrophobic ingredients. The drug contents could reach 4.12% , 2.42% and 3.75%, while the release rate were measured as, 361.79, 55.85 and 104.41 μg·cm·hfor baicalin, berberine and curcumin, respectively. These results indicated that the obtained matrix had good drug-compatibility and drug-release properties for different ingredients.

关键词： drug-release applicable berberine curcumin different

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通过竞争的协调：一种更广泛适用的方法？

Robin Batterham

《工程（英文）》 2016年第2卷第3期页码 286-287 doi: 10.1016/J.ENG.2016.03.009

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Enhancing the efficiency of nitrogen removing bacterial population to a wide range of C:N ratio (1.5:

《环境科学与工程前沿（英文）》 2022年第16卷第8期 doi: 10.1007/s11783-022-1522-y

摘要：

• Simultaneous C & N removal in Methammox occurs at wide C:N ratio.

关键词： Methanogens Biological Nitrogen Removal (BNR) Simultaneous Methammox C:N ratio

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基于适用概率匹配与多维情境驱动的设计知识推送技术 None

Shu-you ZHANG, Ye GU, Xiao-jian LIU, Jian-rong TAN

《信息与电子工程前沿（英文）》 2018年第19卷第2期页码 235-245 doi: 10.1631/FITEE.1700763

摘要：为了提高产品智能设计过程中设计知识的使用效率和质量，有必要向设计人员主动推送设计知识。知识推送主要包括知识匹配和匹配结果的合理推送两个方面。针对现有知识匹配通常缺乏智能性和匹配结果推送缺少个性化的问题，提出基于适用概率匹配和多维情境驱动的设计知识推送技术。构建包括设计知识表示向量、设计案例特征向量和映射布尔矩阵等的训练样本集，通过贝叶斯理论计算设计知识适用与不适用于设计内容的概率，即二者之间的匹配度，得到推送知识集。构建等级化设计内容模型对推送知识集进行过滤，通过设计知识、设计上下文、设计内容和设计人员等多维情境驱动，实现个性化的设计知识推送。在数控机床智能设计平台中的知识推送应用，证明了该技术的可行性和正确性。

关键词：产品设计；知识推送；适用概率匹配；多维情境；个性化

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标题作者时间类型操作

High-order moment methods for LRFD including random variables with unknown probability distributions

Zhao-Hui LU, Yan-Gang ZHAO, Zhi-Wu YU

期刊论文

Range of ecological impact of highway construction in the Longitudinal Range-Gorge Region, China

Jie LIU, Fan CHEN, Haiqing GENG, Xinxin QIU, Binbin CAI,

期刊论文

导航卫星双向伪距时间同步

谭述森

期刊论文