Search | Engineering

订阅投稿

首页工程期刊工程焦点工程成就工程前沿关于我们 English

资源类型

期刊论文 284

会议视频 9

年份

2023 24

2022 29

2021 20

2020 24

2019 16

2018 10

2017 15

2016 10

2015 20

2014 14

2013 12

2012 14

2011 6

2010 12

2009 10

2008 10

2007 9

2006 3

2005 10

2003 6

展开︾

关键词

严格雪崩准则 3

Walsh循环谱 2

三点弯曲梁 2

人工智能 2

农业面源污染 2

医学 2

即时医疗 2

抗击疫情 2

自相关函数 2

2022全球工程前沿 1

2D—3D配准 1

Beclin-1 1

Bent函数 1

Casimir力 1

Chrestenson谱 1

DPP）；分布式功率转换器；开关电容转换器 1

GIS 1

MERS-CoV 1

MPPT）；差分功率处理（Differential power processing 1

展开︾

检索范围：

排序：展示方式：

优化光学亚像素定位精度极限——揭示小PSF的像素相位效应 Article

战海洋, 邢飞, 宝竞宇, 孙婷, 陈真真, 尤政, 袁利

《工程（英文）》 2023年第27卷第8期页码 140-149 doi: 10.1016/j.eng.2023.03.009

摘要：

Subpixel localization techniques for estimating the positions of point-like images captured by pixelated image sensors have been widely used in diverse optical measurement fields. With unavoidable imaging noise, there is a precision limit when estimating the target positions on image sensors, which depends on the detected photon count, noise, point spread function (PSF) radius, and PSF’s intra-pixel position. Previous studies have clearly reported the effects of the first three parameters on the precision limit but have neglected the intra-pixel position information. Here, we develop a localization precision limit analysis framework for revealing the effect of the intra-pixel position of small PSFs. To accurately estimate the precision limit in practical applications, we provide effective PSF (ePSF) modeling approaches and apply the Cramér-Rao lower bound. Based on the characteristics of small PSFs, we first derive simplified equations for finding the best precision limit and the best intra-pixel region for an arbitrary small PSF; we then verify these equations on real PSFs. Next, we use the typical Gaussian PSF to perform a further analysis and find that the final optimum of the precision limit is achieved at the pixel boundaries when the Gaussian radius is as small as possible, indicating that the optimum is ultimately limited by light diffraction. Finally, we apply the maximum likelihood method. Its combination with ePSF modeling allows us to successfully reach the precision limit in experiments, making the above theoretical analysis effective. This work provides a new perspective on combining image sensor position control with PSF engineering to make full use of information theory, thereby paving the way for thoroughly understanding and achieving the final optimum of the precision limit in optical localization.

关键词： Optical measurement Subpixel localization Precision limit optimization Small point spread functions Centroiding Star sensors

HTML PDF 收藏

一种新的通信抗干扰技术体制：预编码跳码扩谱

姚富强,张毅

《中国工程科学》 2011年第13卷第10期页码 69-75

摘要：

基于常规直扩体制的不足，笔者分析了跳码扩谱的必要性，提出和研究了一种新的预编码跳码扩谱通信抗干扰技术体制，重点讨论了预编码跳码扩谱的基本原理与自编码跳码扩谱的异同点、关键技术等，最后分析了其基本性能。该体制和性能已在实际中得到初步验证。

关键词：通信抗干扰直接序列扩谱预编码跳码扩谱自编码跳码扩谱

HTML PDF 收藏

房间之间火灾蔓延过程的网络模型

游宇航,李元洲,霍然

《中国工程科学》 2005年第7卷第7期页码 86-89

摘要：

运用网络模型（networks）对火灾在房间之间的蔓延过程进行了分析；计算不同条件下火灾沿不同路径蔓延的概率和时间，找出其中危险的因素；通过加强安全措施，对火灾蔓延过程进行了有效的控制。结果表明，应用网络模型来分析火灾在房间之间的蔓延过程，可对于蔓延的可能性和危险性作出了较好的预测。

关键词：火灾蔓延房间网络模型路径

HTML PDF 收藏

Aerosol transmission, an indispensable route of COVID-19 spread: case study of a department-store cluster

《环境科学与工程前沿（英文）》 2021年第15卷第3期 doi: 10.1007/s11783-021-1386-6

摘要：

• Aerosol transmission is an indispensable route of COVID-19 spread.

关键词： SARS-CoV-2 COVID-19 Environmental factor Aerosol transmission Epidemiologic characteristic

HTML PDF 收藏

A ruptured recurrent small bowel gastrointestinal stromal tumour causing hemoperitoneum

null

《医学前沿（英文）》 2015年第9卷第1期页码 108-111 doi: 10.1007/s11684-014-0344-0

摘要：

Hemoperitoneum is a rare and potentially life-threatening complication of GIST. We reported a 54-year-old man who developed disseminated intra-abdominal recurrence from a previously resected gastrointestinal stromal tumour (GIST) of the small bowel, and the patient presented with hemoperitoneum. Emergent debulking surgery was performed. A high dose imatinib was prescribed. Despite the presence of residual disease, the patient was well clinically 8 months after the operation. Even though, there is no evidence to support the routine use of debulking surgery in the management of GIST. In our patient, disease progression after second line targeted therapy and the absence of alternative treatment options for spontaneous rupture and hemoperitoneum prompted us to treat the patient aggressively. Resection of the ruptured GIST was carried out for control of bleeding and to prevent recurrent bleeding in this patient with good surgical risks. During the treatment decision-making, the patient’s general condition, the risk of surgery and the extent of dissemination were taken into consideration. In this patient who presented with spontaneous rupture of a small intestinal GIST, the novel use of targeted therapy and aggressive surgical treatment produced reasonably good survival outcome.

关键词： gastrointestinal stromal tumour hemoperitoneum small bowel GIST small bowel neoplasm imatinib

HTML PDF 收藏

基于频率响应函数的动力学模型修正方法研究

朱凼凼,冯咬齐,向树红

《中国工程科学》 2005年第7卷第8期页码 89-94

摘要：

概述了国内外动力学模型修正技术的研究状况，研究了近些年发展起来的基于频响函数的动力学模型修正方法；利用航天器振动试验测量所得的频响函数，从理论上介绍了频响函数残差法、设计参数型频响函数法和摄动型频响函数法三种基于频响函数的动力学模型修正方法，为动力学模型修正技术的发展提供参考。

关键词：航天器动力学频响函数模型修正

HTML PDF 收藏

Silica-based nanoarchitecture for an optimal combination of photothermal and chemodynamic therapy functions

《化学科学与工程前沿（英文）》 2023年第17卷第12期页码 2144-2155 doi: 10.1007/s11705-023-2362-4

摘要： This study introduces multifunctional silica nanoparticles that exhibit both high photothermal and chemodynamic therapeutic activities, in addition to luminescence. The activity of the silica nanoparticles is derived from their plasmonic properties, which are a result of infusing the silica nanoparticles with multiple Cu_2–xS cores. This infusion process is facilitated by a recoating of the silica nanoparticles with a cationic surfactant. The key factors that enable the internal incorporation of the Cu_2–xS cores and the external deposition of red-emitting carbon dots are identified. The Cu_2–xS cores within the silica nanoparticles exhibit both self-boosting generation of reactive oxygen species and high photothermal conversion efficacy, which are essential for photothermal and chemodynamic activities. The silica nanoparticles’ small size (no more than 70 nm) and high colloidal stability are prerequisites for their cell internalization. The internalization of the red-emitting silica nanoparticles within cells is visualized using fluorescence microscopy techniques. The chemodynamic activity of the silica nanoparticles is associated with their dark cytotoxicity, and the mechanisms of cell death are evaluated using an apoptotic assay. The photothermal activity of the silica nanoparticles is demonstrated by significant cell death under near-infrared (1064 nm) irradiation.

关键词： copper sulfide nanoparticles chemodynamic therapy photothermal therapy carbon dots silica nanoparticles

HTML PDF 收藏

论地对空雷达干扰系统在局部战争中的作用及其发展

张锡祥

《中国工程科学》 2000年第2卷第7期页码 55-65

摘要：

文章介绍了从地对空干扰机的发展概况，从单一干扰轰炸瞄准雷达，发展成地对空干扰系统和系列，可以干扰空载作战飞机雷达、导弹制导雷达、精密制导雷达、预警机雷达、星载探测雷达等，分析了这些雷达的干扰原理、干扰方法和干扰机的布局。文章对新体制雷达的干扰压制系数进行了分析，导出各类新体制雷达的干扰压制系数表达式，并提供了计算机仿真和实际试验的结果。文章分析了90年代以来两次现代化局部战争，地对空干扰系统若能发挥作用，将使被入侵国家的损失率下降，使入侵者的损失率升高。地对空干扰系统具有攻防兼备的立体干扰系列功能，需要经费较低，很适合于第三世界国家的需求，具有广泛的发展前景。

关键词：地对空干扰系统在现代化战争中作用发展前景

HTML PDF 收藏

Simulation and experimental improvement on a small-scale Stirling thermo-acoustic engine

Mao CHEN,Yonglin JU

《能源前沿（英文）》 2016年第10卷第1期页码 37-45 doi: 10.1007/s11708-015-0390-6

摘要： Compared with the traditional engines, the thermo-acoustic engines are relatively new and can act as the linear compressors for refrigerators. Many institutes have shown great interest in this kind of machine for its absence of moving mechanical part. In this paper, the influence of the dimensions of the main parts of the small-scale Stirling thermo-acoustic engine was numerically simulated using a computer code called DeltaEC. The resonator and the resonator cavity were found to be the most convenient and effective in improving the performance of the engine. Based on the numerical simulation, a small-scale Stirling thermo-acoustic engine were constructed and experimentally investigated. Currently, with a resonator length of only 1 m, the working frequency of the engine was decreased to 90 Hz and the onset temperature difference was decreased to 198.2 K.

关键词： thermo-acoustic Stirling engine small-scale simulation experiment

HTML PDF 收藏

Discovery of small molecule degraders for modulating cell cycle

《医学前沿（英文）》页码 823-854 doi: 10.1007/s11684-023-1027-5

摘要： The cell cycle is a complex process that involves DNA replication, protein expression, and cell division. Dysregulation of the cell cycle is associated with various diseases. Cyclin-dependent kinases (CDKs) and their corresponding cyclins are major proteins that regulate the cell cycle. In contrast to inhibition, a new approach called proteolysis-targeting chimeras (PROTACs) and molecular glues can eliminate both enzymatic and scaffold functions of CDKs and cyclins, achieving targeted degradation. The field of PROTACs and molecular glues has developed rapidly in recent years. In this article, we aim to summarize the latest developments of CDKs and cyclin protein degraders. The selectivity, application, validation and the current state of each CDK degrader will be overviewed. Additionally, possible methods are discussed for the development of degraders for CDK members that still lack them. Overall, this article provides a comprehensive summary of the latest advancements in CDK and cyclin protein degraders, which will be helpful for researchers working on this topic.

关键词： PROTAC molecular glue degrader cell cycle CDK cyclin

HTML PDF 收藏

Fine-tuning cell organelle dynamics during mitosis by small GTPases

《医学前沿（英文）》 2022年第16卷第3期页码 339-357 doi: 10.1007/s11684-022-0926-1

摘要： During mitosis, the allocation of genetic material concurs with organelle transformation and distribution. The coordination of genetic material inheritance with organelle dynamics directs accurate mitotic progression, cell fate determination, and organismal homeostasis. Small GTPases belonging to the Ras superfamily regulate various cell organelles during division. Being the key regulators of membrane dynamics, the dysregulation of small GTPases is widely associated with cell organelle disruption in neoplastic and non-neoplastic diseases, such as cancer and Alzheimer’s disease. Recent discoveries shed light on the molecular properties of small GTPases as sophisticated modulators of a remarkably complex and perfect adaptors for rapid structure reformation. This review collects current knowledge on small GTPases in the regulation of cell organelles during mitosis and highlights the mediator role of small GTPase in transducing cell cycle signaling to organelle dynamics during mitosis.

关键词： small GTPase cell organelle mitosis

HTML PDF 收藏

Gut microbiota and its implications in small bowel transplantation

null

《医学前沿（英文）》 2018年第12卷第3期页码 239-248 doi: 10.1007/s11684-018-0617-0

摘要：

The gut microbiota is mainly composed of a diverse population of commensal bacterial species and plays a pivotal role in the maintenance of intestinal homeostasis, immune modulation and metabolism. The influence of the gut microbiota on solid organ transplantation has recently been recognized. In fact, several studies indicated that acute and chronic allograft rejection in small bowel transplantation (SBT) is closely associated with the alterations in microbial patterns in the gut. In this review, we focused on the recent findings regarding alterations in the microbiota following SBT and the potential roles of these alterations in the development of acute and chronic allograft rejection. We also reviewed important advances with respect to the interplays between the microbiota and host immune systems in SBT. Furthermore, we explored the potential of the gut microbiota as a microbial marker and/or therapeutic target for the predication and intervention of allograft rejection and chronic dysfunction. Given that current research on the gut microbiota has become increasingly sophisticated and comprehensive, large cohort studies employing metagenomic analysis and multivariate linkage should be designed for the characterization of host–microbe interaction and causality between microbiota alterations and clinical outcomes in SBT. The findings are expected to provide valuable insights into the role of gut microbiota in the development of allograft rejection and other transplant-related complications and introduce novel therapeutic targets and treatment approaches in clinical practice.

关键词： gut microbiota small bowel transplantation acute rejection chronic rejection mucosal immunity biomarker microbiota-targeted therapy

HTML PDF 收藏

Molecular classification of non-small-cell lung cancer: diagnosis, individualized treatment, and prognosis

null

《医学前沿（英文）》 2013年第7卷第2期页码 157-171 doi: 10.1007/s11684-013-0272-4

摘要：

Non-small-cell lung cancer (NSCLC) is the most common cause of premature death among the malignant diseases worldwide. The current staging criteria do not fully capture the complexity of this disease. Molecular biology techniques, particularly gene expression microarrays, proteomics, and next-generation sequencing, have recently been developed to facilitate effectively its molecular classification. The underlying etiology, pathogenesis, therapeutics, and prognosis of NSCLC based on an improved molecular classification scheme may promote individualized treatment and improve clinical outcomes. This review focuses on the molecular classification of NSCLC based on gene expression microarray technology reported during the past decade, as well as their applications for improving the diagnosis, staging and treatment of NSCLC, including the discovery of prognostic markers or potential therapeutic targets. We highlight some of the recent studies that may refine the identification of NSCLC subtypes using novel techniques such as epigenetics, proteomics, or deep sequencing.

关键词： non-small-cell lung cancer molecular typing individualized medicine molecular-targeted therapy gene expression profiling

HTML PDF 收藏

Potential functions of esophageal cancer-related gene-4 in the cardiovascular system

Rui Zhou, Yuanshu Liu, Wenjun Huang, Xitong Dang

《医学前沿（英文）》 2019年第13卷第6期页码 639-645 doi: 10.1007/s11684-019-0701-0

摘要： Esophageal cancer-related gene-4 ( ) is cloned from the normal epithelium of the esophagus. It is constitutively expressed in quiescent epithelial cells and downregulated during tumorigenesis, and expression levels are inversely correlated with the malignant phenotype of tumor cells, validating that is a real tumor suppressor gene. Unlike other tumor suppressor genes that usually encode membrane or intracellular proteins, encodes a 148-amino acid pre-pro-peptide that is tethered on the cell surface in epithelial cells, specialized epithelial cells, and human leukocytes, where it can be processed tissue dependently into several small peptides upon cell activation. Ecrg4 is expressed in a wide variety of other cells/tissues, including cardiomyocytes and conduction system of the heart，, the glomus cells of the carotid body, adrenal glands, choroid plexus, and leukocytes among others, where it exerts distinct functions, such as promoting/suppressing inflammation, inducing neuron senescence, stimulating the hypothalamus–pituitary–adrenal axis, maintaining the stemness of stem cells, participating in the rhythm and rate control of the heart, and possibly gauging the responsiveness of the cardiovascular system (CVS) to hypoxia, in addition to tumor suppression. Here, we briefly review the latest discoveries on Ecrg4 and its underlying molecular mechanisms as a tumor suppressor and focus on the emerging roles of Ecrg4 in the CVS.

关键词： tumor suppressor gene esophageal cancer-related gene-4 cardiovascular disease hypoxia

HTML PDF 收藏

Performance prediction of switched reluctance generator with time average and small signal models

Jyoti KOUJALAGI, B. UMAMAHESWARI, R. ARUMUGAM

《能源前沿（英文）》 2013年第7卷第1期页码 56-68 doi: 10.1007/s11708-012-0216-8

摘要： This paper presents the complete mathematical model and predicts the performance of switched reluctance generator with time average and small signal models. The complete mathematical model is developed in three stages. First, a switching model is developed based on quasi-linear inductance profile. Next, based on the switching behaviour, a time average model is obtained to measure the difference between the excitation and generation time in each switching cycle. Finally, to track control voltage and current wave shapes, a small signal model is designed. The effectiveness of the complete multilevel model combining electrical machine, power converter, load and control with programming language is demonstrated through simulations. A PI controller is used for controlling the voltage of the generator. The results presented show that the controller exhibits accurate tracking control of load voltage under different operating conditions. This demonstrates that the proposed model is able to perform an accurate control of the generated output voltage even in transient situations. The simulation is performed to choose the control parameters and study the performance of switched reluctance generator prior to its actual implementation. Initial experimental results are presented using NI-Data acquisition card to control the output power according to load requirements.

关键词： generator reluctance switching model small signal model time average model