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位置敏感机制深度学习网络 1

低剂量CT；CT成像；全变分；稀疏字典学习 1

低压电器；协同装配；基于规划的人工势场；自适应量子遗传算法；动态交互 1

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Observation of premixed flame fronts by laser tomography

MU Kejin, WANG Yue, LEI Yu, ZHANG Zhedian, NIE Chaoqun, XIAO Yunhan

《能源前沿（英文）》 2008年第2卷第4期页码 427-432 doi: 10.1007/s11708-008-0069-3

摘要： The principle of combustion field detection by using laser tomography, as well as exploitation of the laser tomography apparatus and the tool for image processing is described. An experiment detecting flame fronts by laser tomography was made by employing a V-shaped premixed flame. The results show that the instantaneous geometric shape of flame wrinkles within the light sheet can be clearly resolved. The contours of the flame fronts are precisely tracked through active contour models (ACM) from the digital images of laser tomography, laying the basis for the quantitative analysis of flame wrinkling and propagation.

关键词： combustion tomography apparatus processing exploitation propagation

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A miniature triaxial apparatus for investigating the micromechanics of granular soils with

Zhuang CHENG, Jianfeng WANG, Matthew Richard COOP, Guanlin YE

《结构与土木工程前沿（英文）》 2020年第14卷第2期页码 357-373 doi: 10.1007/s11709-019-0599-2

摘要： The development of a miniature triaxial apparatus is presented. In conjunction with an X-ray micro-tomography (termed as X-ray μCT hereafter) facility and advanced image processing techniques, this apparatus can be used for investigation of the micro-scale mechanical behavior of granular soils under shear. The apparatus allows for triaxial testing of a miniature dry sample with a size of (diameter height). triaxial testing of a 0.4–0.8 mm Leighton Buzzard sand (LBS) under a constant confining pressure of 500 kPa is presented. The evolutions of local porosities (i.e., the porosities of regions associated with individual particles), particle kinematics (i.e., particle translation and particle rotation) of the sample during the shear are quantitatively studied using image processing and analysis techniques. Meanwhile, a novel method is presented to quantify the volumetric strain distribution of the sample based on the results of local porosities and particle tracking. It is found that the sample, with nearly homogenous initial local porosities, starts to exhibit obvious inhomogeneity of local porosities and localization of particle kinematics and volumetric strain around the peak of deviatoric stress. In the post-peak shear stage, large local porosities and volumetric dilation mainly occur in a localized band. The developed triaxial apparatus, in its combined use of X-ray μCT imaging techniques, is a powerful tool to investigate the micro-scale mechanical behavior of granular soils.

关键词： triaxial apparatus X-ray μCT in situ test micro-scale mechanical behavior granular soils

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Multislice computed tomography angiography in the diagnosis of cardiovascular disease: 3D visualizations

Zhonghua Sun

《医学前沿（英文）》 2011年第5卷第3期页码 254-270 doi: 10.1007/s11684-011-0153-7

摘要： Multislice computed tomography (CT) has been widely used in clinical practice for the diagnosis of cardiovascular disease due to its reduced invasiveness and high spatial and temporal resolution. As a reliable alternative to conventional angiography, multislice CT angiography has been recognized as the method of choice for detecting and diagnosing head and neck vascular disease, abdominal aortic aneurysm, aortic dissection, and pulmonary embolism. In patients with suspected coronary artery disease, although invasive coronary angiography still remains as the gold standard technique, multislice CT angiography demonstrates high diagnostic accuracy; in selected patients, it is considered as the first-line technique. The imaging diagnosis of cardiovascular disease is based on a combination of two-dimensional (2D) and three-dimensional (3D) visualization tools to enhance the diagnostic value. This is facilitated by reconstructed visualizations which provide additional information about the extent of the disease, an accurate assessment of the spatial relationship between normal structures and pathological changes, and pre-operative planning and post-procedure follow-up. The aim of the present article is to present an overview of the diagnostic performance of various 2D and 3D CT visualizations in cardiovascular disease, including multiplanar reformation, maximum intensity projection, volume rendering, and virtual intravascular endoscopy. The recognition of the potential value of these visualizations will assist clinicians in efficiently using the multislice CT imaging modality for the diagnostic management of patients with cardiovascular disease.

关键词： cardiovascular disease multislice computed tomography three-dimensional reconstruction diagnosis visualization

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A multi-probe micro-fabrication apparatus based on the friction-induced fabrication method

Zhijiang WU, Chenfei SONG, Jian GUO, Bingjun YU, Linmao QIAN

《机械工程前沿（英文）》 2013年第8卷第4期页码 333-339 doi: 10.1007/s11465-013-0276-4

摘要：

A novel multi-probe micro-fabrication apparatus was developed based on the friction-induced fabrication method. The main parts of the apparatus include actuating device, loading system, and control system. With a motorized linear stage, the maximum fabrication area of 50 mm × 50 mm can be achieved, and the maximum sliding speed of probes can be as high as 10 mm/s. Through locating steel micro balls into indents array, the preparation of multi-probe array can be realized by a simple and low-cost way. The cantilever was designed as a structure of deformable parallelogram with two beams, by which the fabrication force can be precisely controlled. Combining the friction-induced scanning with selective etching in KOH solution, various micro-patterns were fabricated on Si(100) surface without any masks or exposure. As a low-cost and high efficiency fabrication device, the multi-probe micro-fabrication apparatus may encourage the development of friction-induced fabrication method and shed new light on the texture engineering.

关键词： friction-induced fabrication silicon surface texture friction multi-probe

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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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Near-infrared fluorescent probe for fast track of cyclooxygenase-2 in Golgi apparatus in cancer cells

Bhaskar Gurram, Miao Li, Jiangli Fan, Jingyun Wang, Xiaojun Peng

《化学科学与工程前沿（英文）》 2020年第14卷第1期页码 41-52 doi: 10.1007/s11705-019-1796-1

摘要： Cyclooxygenase-2 (COX-2) has been used as an excellent traceable biomarker, and exists maximally in Golgi apparatus (Cancer cells). Celecoxib (CCB) is a selective inhibitor for COX-2, and has been used as one of non-steroidal anti-inflammatory drug. Herein we report the conjugation of nile blue (NB) with CCB via a six-carbon linkage to form a fluorescence probe NB-C6-CCB for the detection of COX-2. NB-C6-CCB displays strong fluorescence with the emission peak centered at near-infrared wavelength (700 nm) in tumor cells or tumor tissues with high expression of COX-2. Importantly, NB-C6-CCB can discriminate cancer cells (MCF-7) fluorescence intensity from normal ones (COS-7) in the co-culture medium under confocal microscope. Subcellular localization of the NB-C6-CCB preferentially points to the Golgi apparatus and increases the fluorescent intensity. The competitive analysis (with CCB) and Native-PAGE analysis confirmed that NB-C6-CCB shows selective binding affinity towards COX-2 enzyme. Competitive analysis with CCB (flow cytometry assay) revealed the fluorescence intensity fluctuation due to pretreatment of CCB with different concentrations, indicating that the NB-C6-CCB is a precise or sensitive probe for the COX-2. Tumor tissue (depth: 500 µm), organs and mice imaging tests show excellent near-infrared visualization, specific localization and identification of tumors.

关键词： cyclooxygenase-2 nile blue CCB Golgi apparatus NIR imaging

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Kawai型碳化钨多面砧压机的压力突破 Review

Takayuki Ishii, 刘兆东, Tomoo Katsura

《工程（英文）》 2019年第5卷第3期页码 434-440 doi: 10.1016/j.eng.2019.01.013

摘要：

在众多领域中都需要扩大Kawai型碳化钨（tungsten carbide, WC）多面砧压机的压力范围，尤其是在地球科学领域。然而，40年来，在压力产生方面没有取得重大进展。我们最近的研究已经将采用碳化钨压砧的Kawai型多面砧压机的压力产生范围扩大到65 GPa，这是该装置高压产生范围的世界纪录，比传统压力产生范围增大了2.5倍以上。我们还成功地在高温下产生了约50 GPa的压力。本文回顾了我们最近发展的高压技术。室温和高温下高压的产生是通过以下技术的结合来实现的：①精确对准的滑块系统；②高硬度的二级压砧；③二级砧面锥形化；④由高体积模量材料组成的高压腔体；⑤炉体隔热性高。我们的高压技术将有助于研究在下地幔上部条件下材料的相稳定性和物理性质，并且能够合成和表征新材料。

关键词：高压多面砧压机碳化钨压砧烧结的金刚石压砧下地幔

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of plotting sensor sensitivity field and image reconstruction algorithm for electrical capacitance tomography

CHEN De-yun, YANG Cong-jing, ZHENG Gui-bin, YU Xiao-yang, SUN Li-juan

《机械工程前沿（英文）》 2006年第1卷第2期页码 242-247 doi: 10.1007/s11465-006-0008-0

摘要： Sensor sensitivity field in electrical capacitance tomography is affected by the distribution of multiphase medium, which is the peculiarity of soft field. This brings great difficulty for image reconstruction. To improve the quality of image reconstruction, it is important to analyze the distribution of the sensitivity field. In this article, using the finite element method, we expound a kind of novel plotting pattern to field, which is the distribution of sensitivity field through computer simulation. From experiments and results of sensitivity field analysis, a novel method of image reconstruction based on genetic algorithms is presented. The finite element model is correct and simulation result is fine by adopting unequal interval plotting patterns. At the same time, the result of image reconstruction has high precision.

关键词： multiphase unequal interval capacitance tomography pattern sensitivity

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珊瑚岛礁环境噪声成像 Article

夏少红, 张昌榕, 曹敬贺

《工程（英文）》 2023年第25卷第6期页码 182-193 doi: 10.1016/j.eng.2021.09.022

摘要：

As valuable land in the ocean, coral islands are not only important bases for making use of marine resources and protecting marine rights and interests, but also important for breakthrough research in many fields of earth science. Hence, the economical and efficient determination of the underground structure of coral islands has become significant in coral island engineering geology, but remains challenging for traditional marine geophysical prospecting and drilling methods. While ambient noise tomography with dense arrays has been widely used in continental regions, its applicability to coral islands remains undetermined. In this study, based on the data recorded by a dense array on an isolated coral island in the South China Sea, we analyzed the ambient noise characteristics and obtained a 3D subsurface structure of the coral island using ambient noise tomography. We made the following findings: ① The ambient noise frequencies can be roughly categorized into three levels: < 1, 1–5, and > 5 Hz. The spectral characteristics of the noise below 5 Hz were consistent at different stations, but there were significant differences in the characteristics of the noise above 5 Hz. ② For ambient noise frequencies below 5 Hz, cross-correlation functions with high quality could be obtained with only 24 h of waveform data. However, it was difficult to extract meaningful cross-correlation functions for ambient noise frequencies above 5 Hz. ③ The S-wave velocity in the coral island was higher toward the sea and lower toward the lagoon, which was consistent with the high degree of cementation of the outer reef flat stratum on the seaward side. ④ There were two low-velocity horizons at 25–75 and 200–300 m, which were in good agreement with the high-porosity horizons that were revealed by drilling core samples, reflecting the weathering history of the reef. Our research demonstrates that ambient noise tomography is a potentially economical, efficient, and environmentally friendly method for the geological prospecting of coral reefs.

关键词： Coral island Ambient noise tomography Engineering geology South China Sea

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properties of municipal solid waste incineration residues with cement and coal fly ash using X-ray Computed Tomography

Toshifumi MUKUNOKI, Ta Thi HOAI, Daisuke FUKUSHIMA, Teppei KOMIYA, Takayuki SHIMAOKA

《结构与土木工程前沿（英文）》 2019年第13卷第3期页码 640-652 doi: 10.1007/s11709-018-0502-6

摘要： A significant volume of Municipal Solid Waste incineration bottom ash and fly ash (i.e., incineration residues) are commonly disposed as landfill. Meanwhile, reclamation of landfill sites to create a new land space after their closure becomes an important goal in the current fewer and fewer land availability scenario in many narrow countries. The objective of this study is to reclaim incineration residue materials in the landfill site by using cement and coal fly ash as stabilizers aiming at performing quality check as new developed materials before future construction. Indeed, physical and mechanical properties of these new materials should be initially examined at the micro scale, which is the primary fundamental for construction at larger scale. This research examines quantitative influences of using the combination of cement and coal fly ash at different ratio on the internal structure and ability of strength enhancement of incineration residues when suffering from loading. Couple of industrial and micro-focus X-ray computed tomography (CT) scanners combined with an image analysis technique were utilized to characterize and visualize the behavior and internal structure of the incineration residues-cement-coal fly ash mixture under the series of unconfined compression test and curing period effect. Nine types of cement solidified incineration residues in term of different curing period (i.e., 7, 14, 28 days) and coal fly ash addition content (i.e., 0%, 9%, 18%) were scanned before and after unconfined compression tests. It was shown that incineration residues solidified by cement and coal fly ash showed an increase in compression strength and deformation modulus with curing time and coal fly ash content. Three-dimension computed tomography images observation and analysis confirmed that solidified incineration residues including incineration bottom and fly ash as well as cement and coal fly ash have the deliquescent materials. Then, it was studied that stabilized parts play a more important role than spatial void distribution in increment or reduction of compression strength.

关键词： mechanical property municipal solid waste incineration residues coal fly ash unconfined compression test image analysis X-Ray Computed Tomography scanners

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Simultaneous acquisition of CT angiography and whole brain CT perfusion images by using multiphase dynamic helical scan on 16 MDCT

Weiwei CHEN, Jianpin QI, Wenzhen ZHU, Wenhua HUANG, Jinmei SONG

《医学前沿（英文）》 2009年第3卷第2期页码 230-235 doi: 10.1007/s11684-009-0023-8

摘要： We implemented a new protocol — multiphase dynamic helical scan to acquire CT angiography (CTA) and whole brain CT perfusion (CTP) images simultaneously with single scan on 16 multidetector CT (MDCT). A total of 90 patients who were randomly assigned into 3 groups were included in our study. Each group underwent CT scan by using the new protocol, traditional CTA and CTP protocol, respectively. The image quality of CTA, the CTP parameter values and the X-ray doses were measured and compared between the new protocol and the traditional protocols. There was no statistically significant difference in the CTA image quality between the above methods ( =0.55). For CTP parameters, the new protocol tended to overestimate the blood volume (BV) and blood flow (BF) value, and to underestimate the mean transit time (MTT) value compared with the traditional method. However, there was no statistically significant difference in BV, BF, and MTT value between the two methods except permeability surface (PS) ( >0.05). The volume CT dose index (CTDIvol) and dose length product (DLP) of our protocol were lower than the traditional one. The new protocol can obtain valuable diagnostic information in a shorter time without significant compromise in image quality. In addition, it reduces the radiation dose as well as contrast medium usage on the patient.

关键词： computed tomography angiography computed tomography perfusion

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Fatigue of asphalt binder, mastic and mixture at low temperature

Dong WANG, Linbing WANG, Guoqing ZHOU

《结构与土木工程前沿（英文）》 2012年第6卷第2期页码 166-175 doi: 10.1007/s11709-012-0157-7

摘要： The fatigue damage is one of the most common distresses observed on the asphalt concrete pavement. To thoroughly understand the fatigue of asphalt concrete, the behaviors of the major components of asphalt concrete under cyclic loading are investigated respectively in this study. A new experiment method is developed to evaluate the performances of asphalt binder, mastic and fine aggregates mixture under cyclic tensile loading. The fatigue test results of asphalt binder show that the fatigue performance of asphalt binder is closely related with loading magnitude, temperature and loading rate. Mastic specimens with different filler content are tested and the results indicate that mastic specimens with 30% filler content show better fatigue resistance and higher permanent strain. The micro-structure analysis of mastic and mixture indicates that the fatigue resistance is closely related with the air void content of specimen. 3D digital specimens are developed to model the fatigue of the asphalt binder, mastic and mixture specimens based on the finite element method (FEM). Fatigue damage of asphalt concrete is simplified by a damage model. With proper selection of damage parameters, the simulation results agree well with laboratory test results and can be used as a basis for future fatigue research.

关键词： fatigue asphalt mixture asphalt binder mastic finite element method (FEM) X-ray tomography

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基于多声源波速结构成像的岩体异常区域超前辨识方法 Article

董陇军, 裴重伟, 谢鑫, 张义涵, 闫先航

《工程（英文）》 2023年第22卷第3期页码 191-200 doi: 10.1016/j.eng.2022.05.016

摘要：

异常区域超前辨识对于预防地下岩土工程灾害具有重要作用。为了满足地下工程高精度探测的需求，本文提出一种层析成像方法以辨识复杂岩体结构中的异常区域，结合了走时层析、阻尼最小二乘法和高斯滤波等技术。该方法克服了空洞区域辨识中速度差限制，减轻了迭代中孤立速度突变所带来的影响。开展了数值和室内实验，量化评估最短路径法（shortest-path method, SPM）、动态最短路径法（dynamic shortest-path method, DSPM）和快速扫描法（fast sweeping method, FSM）等正演模拟的识别精度和计算效率。结果表明，在数值和室内实验中DSPM和FSM均能清晰地辨识出异常区域。陕西震奥矿山现场应用结果证明了该方法可利用矿山开采中爆破、微震等多类声源对矿山内部未知结构进行波速场成像。本研究不仅实现了走时层析成像方法在异常区域识别中的应用，而且为地下岩土工程中潜在风险源的探测提供了新的思路。

关键词：地下工程走时层析复杂结构异常区域辨识射线追踪

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A new method of studying collapsibility of loess

Yuanqing ZHU , Zhenghan CHEN ,

《结构与土木工程前沿（英文）》 2009年第3卷第3期页码 305-311 doi: 10.1007/s11709-009-0040-3

摘要： A new triaxial testing system that could control suction in wetting-induced collapsible tests was successfully developed to study the suction effects on wetting-induced collapsible deformation. The pedestal of the triaxial cell was made up of two parts, and the equipment not only could control suction but also could make water accessible to soil. A pressure/volume-controlled equipment was combined with the triaxial system to measure the water volume absorbed by samples accurately and to add pressure on water to filtrate into the sample. The apparatus could measure volume change precisely and keep the deviator stress unvaried, as well as measure the volume of water filtrating into the samples exactly. A triaxial collapsible testing procedure was described using the new apparatus for undisturbed collapsible loess with controlled suction. Furthermore, a series of double triaxial collapsible tests were conducted under different suctions and the same net cell pressure, and tests under different net cell pressures and the same suction were also done. It was indicated that the collapsible deformation increased with the increasing suction, and the effect of the net cell pressure on collapsible deformation was remarkable. The new triaxial apparatus was a useful facility to study the collapsible behavior of loess.

关键词： triaxial apparatus for collapsible soils controlled suction pressure/volume controlled equipment double triaxial collapsible test single triaxial collapsible test

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Low-dose CT for lung cancer screening: opportunities and challenges

null

《医学前沿（英文）》 2018年第12卷第1期页码 116-121 doi: 10.1007/s11684-017-0600-1

摘要：

Lung cancer is among the most frequently diagnosed cancers worldwide and the leading cause of cancer death in both males and females. Screening for lung cancer coupled with earlier intervention has long been studied as an approach to mortality reduction. However, minimal progress was achieved until recently, when low-dose spiral computed tomography (LDCT) screening demonstrated a 20% reduction in mortality from lung cancer in a randomized controlled trial (RCT), the National Lung Screening Trial, from the United States. On the basis of this finding, LDCT has been recommended for lung cancer screening in high-risk populations by several clinical guidelines. However, results from the following independent RCTs in Europe failed to show consistent conclusions. In addition, intractable problems gradually emerged with the progress of LDCT screening. This paper summarizes and discusses the main observations and challenges of LDCT screening for lung cancer. Before spreading implementation of LDCT screening, challenges, including high false-positive rates, overdiagnosis, enormous costs, and radiation risk, must be addressed. Complementary biomarkers and technical improvement are expected in the field of lung cancer screening in the near future.

关键词： lung cancer low-dose computerized tomography early detection opportunities challenges