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Miniaturized power detection module operating in millimeter wave band

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Journal of Electronic Science and Technology 2024年第2期22卷 69-76页

作者： Xiang Zhou zhi-Yong Zhong School of Electronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu611731China

The miniaturized broadband detection module can be embedded into the microwave application system such as the front end of the transmitter to detect the power or other parameters in real *** is highly prospective in military and scientific *** this paper,a broadband power detection module operating at 2..5 GHz-40.0 GHz is designed by using low-barrier Schottky diode as the detector and a comparator for threshold *** module can dynamically detect the power range between-10 dBm and 10 dBm with the detection accuracy of 0.1 ***,the temperature compensation circuit is also applied to improve the measurement *** a result,the resulted error low to±1 dB in the temperature range of -55℃ to +85℃ is *** designed module is encapsulated by a Kovar alloy with a small volume of 9 mm×6 mm×3 *** endows the designed module the advantages of small size,easy integration,and low cost,and even it is applicable to high-reliability environments such as satellites.

关键词： Diode Miniaturization Power detection Temperature compensation

Few-shot skin cancer detection based on many-objective optimization

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Kongzhi yu Juece/Control and Decision 2024年第11期39卷 3597-3606页

作者： Zhao, Jia-Hui Wen, jie Cai, Xing-Juan Cui, zhi-Hua Shanxi Key Laboratory of Big Data Analysis and Parallel Taiyuan University of Science and Technology Taiyuan 030024 China Shanxi Key Laboratory of Advanced Control and Equipment Ⅰntelligence Taiyuan University of Science and Technology Taiyuan 030024 China

Due to the long-tailed distribution characteristics of skin cancer data, quickly identifying rare skin disease samples with small amounts of data becomes a challenging few-shot problem. The detection method based on meta-learning can quickly learn meta-knowledge from the majority of common classes skin disease classes and use prior knowledge to improve the model’s ability to detect rare skin diseases. However, the bias in the quality and distribution of public skin cancer categories leads to the risk of overfitting in the pre-training phase of meta-learning, and meta-learning models based on traditional networks struggle to handle fine-grained skin disease problems. Affronting this issue, a many-objective meta-learning skin cancer detection model is proposed. The proposed model optimizes the distribution of common classes (base classes) by considering various classification performances of the skin cancer detection model, thus obtaining quality-enhanced training samples. And it adopts the ResNet12.network structure integrated with the CCNet attention model, which can significantly enhance the ability to identify fine-grained skin lesion images. Additionally,an improved many-objective optimization algorithm with discrete grouping strategy is designed to efficiently solve the proposed model. Some experiments are conducted on two public medical datasets, ⅠSCⅠ2.18 and Derm7pt. The proposed many-objective skin detection model achieves detection accuracies of 67 %, 79 %, and 82.% respectively on binary classification tasks with 1-shot, 3-shot, and 5-shot learning,which validates the effectiveness of the model. © 2.2. Northeast University. All rights reserved.

关键词： Contrastive Learning

Experimental study on combustion characteristics of supersonic combustor based on alternating-wedge strut

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Chinese Journal of Aeronautics 2024年第5期37卷 214-227页

作者： jie LI Wenyan SONG Yuhang WANG School of Power Energy Northwestern Polytechnical UniversityXi’an 710129China

Acetone Planar Lase-Induced Fluorescence(PLIF)and OH-PLIF were employed to capture the fuel distribution and OH distribution downstream for the supersonic combustor based on the alternating-wedge *** combustion establishment process and combustion mode in the combustor under different fuel injection methods and different equivalence ratios were *** with the kerosene-PLIF and OH-PLIF results in the cavity combustor,a comparative analysis was conducted to understand the combustion characteristics and combustion modes between the alternating-wedge strut-based combustor and the cavity-based *** results show that the combustor is in weak combustion mode in the case of low equivalence ratio,and the combustor is in intensive combustion mode in the case of high equivalence *** lower limit of the equivalence ratio of the combustor to maintain the intensive combustion mode varies based on different fuel injection *** OH distribution under reacting condition has a strong correlation with the fuel distribution under non-reacting *** OH fluorescence signal near the injector is weaker when the fuel distribution is more *** injector position located at the base of the strut rear has better mixing performance,enabling the combustor to be in intensive combustion mode at a lower equivalence *** combustion reaction in the alternating-wedge strut-based combustor is not necessarily dominated by mass transfer due to the mixing enhancement and premixed zone downstream of strut,while the combustion reaction process in the cavity-based combustor is mainly influenced by mass transfer.

关键词： Supersonic combustor Alternating-wedge strut Cavity PLIF Fuel injection Fuel distribution Combustion characteristics Combustion mode

Emerging direct current triboelectric nanogenerator for high-entropy mechanical energy harvesting

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Science China(Technological Sciences) 2024年第5期67卷 1297-1316页

作者： CHEN jie GUO RuiLong GUO HengYu College of Physics and Electronic Engineering Chongqing Normal UniversityChongqing 401331China Department of Applied Physics Chongqing UniversityChongqing 401331China

In the era of the Internet of Things(IoT),the provision of sustainable power to distributed,mobile,and low-power-consumption electronic devices is a critical *** overcome this challenge,the triboelectric nanogenerator(TENG),a highly efficient high-entropy mechanical energy harvesting device,was developed in *** device enables the direct conversion of irregular and low-frequency mechanical energy into pulsed alternating current(AC)***,the incompatibility of most electronic devices with AC signals necessitates rectifier circuits or generators that deliver direct current(DC)*** recent years,DC-TENGs have undergone extensive development,achieving significant milestones in various application fields while also facing crucial challenges that require *** this review,three categories of DC-TENG devices with distinct operating mechanisms are comprehensively explored:multiphase coupling,mechanical rectification,and air *** typical structures and working mechanisms are thoroughly discussed,and specific output performance limitations,along with corresponding optimization strategies,are ***,the applications of DC-TENGs in various scenarios are ***,the challenges faced by DC-TENGs and potential solutions are analyzed to guide further advancements in this technology.

关键词： TENG direct current working mechanisms output performance limitations optimization strategies

Gene therapy for monogenic disorders: challenges, strategies, and perspectives

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Journal of Genetics and Genomics 2024年第2期51卷 133-143页

作者： Yi Zhang zhi-Ying Wu Department of Medical Genetics and Center for Rare Diseases Second Affiliated HospitalZhejiang University School of MedicineHangzhouZhejiang 310009China Department of Neurology Second Affiliated HospitalZhejiang University School of MedicineHangzhouZhejiang 310009China Key Laboratory of Medical Neurobiology of Zhejiang Province HangzhouZhejiang 310009China

Monogenic disorders refer to a group of human diseases caused by mutations in single genes. While disease-modifying therapies have offered some relief from symptoms and delayed progression for some monogenic diseases, most of these diseases still lack effective treatments. In recent decades, gene therapy has emerged as a promising therapeutic strategy for genetic disorders. Researchers have developed various gene manipulation tools and gene delivery systems to treat monogenic diseases. Despite this progress, concerns about inefficient delivery, persistent expression, immunogenicity, toxicity, capacity limitation, genomic integration, and limited tissue specificity still need to be addressed. This review gives an overview of commonly used gene therapy and delivery tools, along with the challenges they face and potential strategies to counter them.

关键词： Gene therapy Monogenic diseases Geneediting Genedelivery Challenges

SG-NeRF:Sparse-Input Generalized Neural Radiance Fields for Novel View Synthesis

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Journal of Computer Science & Technology 2024年第4期39卷 785-797页

作者： Kuo Xu jie Li Zhen-Qiang Li Yang-jie Cao School of Cyber Science and Engineering Zhengzhou UniversityZhengzhou 450002China Intelligent Big Data System(iBDSys)Lab Shanghai Jiao Tong UniversityShanghai 200240China School of Computer and Artificial Intelligence Zhengzhou UniversityZhengzhou 450001China

Traditional neural radiance fields for rendering novel views require intensive input images and pre-scene optimization,which limits their practical *** propose a generalization method to infer scenes from input images and perform high-quality rendering without pre-scene optimization named SG-NeRF(Sparse-Input Generalized Neural Radiance Fields).Firstly,we construct an improved multi-view stereo structure based on the convolutional attention and multi-level fusion mechanism to obtain the geometric features and appearance features of the scene from the sparse input images,and then these features are aggregated by multi-head attention as the input of the neural radiance *** strategy of utilizing neural radiance fields to decode scene features instead of mapping positions and orientations enables our method to perform cross-scene training as well as inference,thus enabling neural radiance fields to generalize for novel view synthesis on unseen *** tested the generalization ability on DTU dataset,and our PSNR(peak signal-to-noise ratio)improved by 3.14 compared with the baseline method under the same input *** addition,if the scene has dense input views available,the average PSNR can be improved by 1.04 through further refinement training in a short time,and a higher quality rendering effect can be obtained.

关键词： Neural Radiance Fields(NeRF) multi-view stereo(MVS) new view synthesis(NVS)

Perspective on new cell-free DNA technologies for early cancer detection

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Cancer Biology & Medicine 2024年第2期21卷 139-143页

作者： jie Li Xun Lan Department of Basic Medical Sciences School of MedicineTsinghua UniversityBeijing 100084China MOE Key Laboratory of Bioinformatics Tsinghua UniversityBeijing 100084China Tsinghua-Peking Joint Center for Life Sciences Tsinghua UniversityBeijing 100084China

High cancer heterogeneity and aggressiveness are major factors contributing to the poor prognosis of patients with advanced cancer~(1-5).Early detection of cancer can significantly improve the prognosis of patients with early-stage cancer after standard *** traditional cancer detection technologies,such as endoscopy for gastrointestinal cancer,mammography for breast cancer。

关键词： prognosis cancer patients

Exclusive enteral nutrition for treating pediatric Crohn’s disease

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World Journal of Pediatrics 2024年第9期20卷 869-871页

作者： Yu Yu jie Chen Department of Gastroenterology Children’s HospitalNational Clinical Research Center for Child HealthZhejiang University School of MedicineHangzhou 310052China

Crohn's disease(CD),an enduring and relapsing condition afecting the gastrointestinal tract,manifests in a spectrum of symptoms and clinical manifestations that can profoundly afect quality of life[1].Recently,CD has emerged as a global burden of *** China,the prevalence and incidence of childhood infammatory bowel disease(IBD)have steadily increased,from 0.5 per 1 million in 2.01 to 6.0 per 1 million in 2.10[2..Pediatric patients often face a longer treatment duration than adults.

关键词： Crohn pediatric nutrition

Analyzing the surface passivity effect of germanium oxynitride:a comprehensive approach through first principles simulation and interface state density

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Nuclear Science and Techniques 2024年第5期35卷 74-84页

作者： Sheng-jie Du Xiu-Xia Li Yang Tian Yuan-Yuan Liu Ke Jia Zhong-Zheng Tang Jian-Ping Cheng zhi Deng Yu-Lan Li Zheng-Cao Li Sha-Sha Lv College of Nuclear Science and Technology Joint Laboratory of Jinping Ultra‑Low Radiation Background Measurement of Ministry of Ecology and Environment Key Laboratory of Beam Technology of Ministry of Education Beijing Normal UniversityBeijing Normal UniversityBeijing 100875China Joint Research Center Nuctech Company LimitedBeijing 100084China Department of Engineering Physics Key Laboratory of Particle&Radiation Imaging of Ministry of EducationTsinghua UniversityBeijing 100084China Key Laboratory of Advanced Materials(MOE) School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China

High-purity germanium(HPGe)detectors,which are used for direct dark matter detection,have the advantages of a low threshold and excellent energy *** surface passivation of HPGe has become crucial for achieving an extremely low energy *** this study,first-principles simulations,passivation film preparation,and metal oxide semiconductor(MOS)capacitor characterization were combined to study surface *** calculations of the energy band structure of the -H,-OH,and -NH_(2. passivation groups on the surface of Ge were performed,and the interface state density and potential with five different passivation groups with N/O atomic ratios were accurately analyzed to obtain a stable surface *** on the theoretical calculation results,the surface passivation layers of the Ge_(2.ON_(2. film were prepared via magnetron sputtering in accordance with the optimum atomic ratio *** microstructure,C-V,and I-V electrical properties of the layers,and the passivation effect of the Al/Ge_(2.ON_(2./Ge MOS were characterized to test the interface state *** mean interface state density obtained by the Terman method was 8.4×10^(11) cm^(-2. eV^(-1).The processing of germanium oxynitrogen passivation films is expected to be used in direct dark matter detection of the HPGe detector surface passivation technology to reduce the detector leakage currents.

关键词： Surface passivation High purity germanium detector Germanium nitrogen oxide Interface state density