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建筑走廊内相邻防烟分区不同排烟方式相互影响研究

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暖通空调 2025年第1期55卷 52-56页

作者：王雪梁强中国人民警察大学廊坊065000

同一防火分区内相邻防烟分区采用不同排烟方式可能会对排烟造成不利影响。以某一医院走廊为例,采用FDS软件对同一防火分区采用不同排烟方式时的排烟效率进行分析。结果表明:机械排烟对自然排烟的排烟效果会产生影响;自然排烟会对机械排... 详细信息

同一防火分区内相邻防烟分区采用不同排烟方式可能会对排烟造成不利影响。以某一医院走廊为例,采用FDS软件对同一防火分区采用不同排烟方式时的排烟效率进行分析。结果表明:机械排烟对自然排烟的排烟效果会产生影响;自然排烟会对机械排烟的启动时间有影响;对于本建筑排烟系统,自然排烟窗与机械排烟口正对设置情况下的整体控烟效果更好。相邻防烟分区采用不同排烟方式时,建议采用性能化方式进行优化设计。

关键词：火灾走廊排烟排烟效率排烟系统排烟口机械排烟自然排烟防烟分区

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Experimental Study on Inducement and Development of Flow Instabilities in a Centrifugal Compressor with Different Diffuser Types

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Journal of Thermal Science 2020年第2期29卷 435-444页

作者： xue Xiang WANG Tong Gas Turbine Research Institute Shanghai Jiao Tong UniversityShanghai 200240China

A centrifugal compressor is a typical compressed air energy storage device. In order to ensure the safety of the compressed energy storage process in the compressor, the internal unsteady flow phenomena need to be closely monitored, especially some serious ones like stall and surge. It is necessary to explore the mechanism of flow instabilities under different conditions. A centrifugal air compressor was tested with a vaneless diffuser and a variable vaned diffuser with five different vane setting angles, respectively. Various diffuser types resulted in various modes of flow instabilities prior to surge. The vaneless region between the impeller and the diffuser was focused on. Multiple high-speed sensors were arranged along the circumferential direction. The pressure signals at all these positions were being measured and collected in real time as the compressor was slowly throttled into surge. This paper emphasizes on the influence of matching between the impeller and the diffuser on the flow instability. The experimental results showed that the diffuser vane setting angle affected the stall characteristics. Due to the asymmetry of the volute, the circumferential pressure distribution was always severely distorted prior to surge. A high-pressure region appeared near the volute tongue, and a low-pressure region was formed away from the volute tongue. In the case of the vaned diffuser with non-design installation angle and the vaneless diffuser, the rotating stall signal was originated in the low-pressure region and propagated circumferentially. However, in the case of the vaned diffuser with the design installation angle, the circumferential high-pressure region became the most sensitive region for the generation of stall, and another form of instability occurred there. Both the inducement and development of these flow instabilities have been studied. The dynamic experimental research on the compressor matching different types of diffusers could be a good case supple

关键词： compressed air energy storage centrifugal compressor flow instability stall

A multiscale view in functional materials

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Progress in Natural Science:Materials International 2022年第6期32卷 674-683页

作者： Guoqiang Shi Dongfeng xue Multiscale Crystal Materials Research Center Shenzhen Institute of Advanced Technology Chinese Academy of Sciences

Functional materials show various highly demanded performances originating from intrinsic features related to degrees of freedom in a lattice ***,deep physical or chemical insights of quantum materials stimulate researchers to clarify multiscale processes within both materials and devices,which may be understood as functional materials that possess energy origin beyond electron *** is of great significance for the design of functional materials to understand the sources of properties of functional materials from the perspective of multi degrees of freedom via multiscale research *** short review illustrates the importance and explores the energy source of functional materials from multiple degrees of freedom ***,we analyzed the multiple degrees of freedom within lithium niobate single crystals to clarify their multiscale *** short review may,in some cases,provide a perspective for enhancing research scopes of functional materials and recommending some methodologies from multiple degrees of freedom perspectives.

关键词： Degrees of freedom Functional crystals Lithium niobate

Intelligent Assessment of Active and ReactivePower Flow with Satisfying Accuracy forN-k_(1)-k_(2) Cascading Outages

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Journal of Modern Power Systems and Clean Energy 2021年第5期9卷 986-999页

作者： Yusheng xue Yun Liu NARI Group Corporation(State Grid Electric Power Research Institute) NanjingChina School of Electrical Engineering Shandong UniversityJinanChina

Addressed to the N-k_(1)-k_(2) cascading outages,it is computationally burdensome for the reliable calculation of active and reactive power *** paper builds a comprehensive framework with three algorithms,including the distribution factor(DF),the Newton-Raphson(NR),and the first iteration of NR algorithm(termed as 1J).Classifiers are designed to determine whether the NR algorithm should be employed for *** features are extracted upon the analytical error of *** reactive power is partially considered in the 1J but neglected in the DF algorithm,the deviation between the solutions is taken as one crucial *** support vector machine(SVM)is then utilized for classifier *** the deep integration of the causal inference and the statistical paradigm,this framework calculates active and reactive power flows rapidly,reliably,and *** effectiveness and robustness are fully validated in three typical IEEE systems.

关键词： Active power flow algorithm coordination causal algorithm integration of research paradigms N-k_(1)-k_(2)cascading outage reactive power flow

Quantitative Assessment for Commutation Security Based on Extinction Angle Trajectory

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Journal of Modern Power Systems and Clean Energy 2021年第2期9卷 328-337页

作者： Qi Tao Yusheng xue the School of Electrical Engineering Zhejiang UniversityHangzhou 310000China NARI Group Corporation(State Grid Electric Power Research Institute) Nanjing 211106China

In order to reduce the risk of commutation failure(CF)in the AC/DC hybrid power system,the quantitative analysis on CF is required for on-line assessment and optimal *** paper presents an accurate and reliable method to quantify the commutation security based on the trajectory due to the complexity of the high-voltage direct current(HVDC)***,the characteristics of the extinction angle trajectory are analyzed under both commutation success and failure *** commutation security margin index(CSMI)is then proposed for the HVDC ***,a search strategy for parameter limits is put forward based on the sensitivity analysis of CSMI to accelerate the search speed with a guaranteed accuracy level.A modified IEEE 39-bus power system and an actual large-scale power system with 46 generators and 821 buses are utilized to verify the validity and robustness of the proposed index and strategy.

关键词： AC/DC hybrid power system commutation failure(CF) commutation security margin high-voltage direct current(HVDC) security limit

Individualized treatment guided by endoscopic ultrasound-guided fine-needle aspiration for adrenocortical oncocytoma:A case report

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World Journal of Clinical Oncology 2025年第2期16卷 158-164页

作者： Han Chen xue Jing Department of Gastroenterology The Affiliated Hospital of Qingdao UniversityQingdao 266000Shandong ProvinceChina

BACKGROUND Adrenocortical oncocytoma is a rare,mostly benign,nonfunctional tumor that is typically detected *** diagnosis is challenging because of the absence of distinctive imaging characteristics,necessitating pathological *** SUMMARY We present a case report of a 35-year-old woman with an adrenal mass located on the left side,where endoscopic ultrasound-guided fine-needle aspiration(EUSFNA)was performed after comprehensive diagnostic *** results are consistent with those of previously documented cases regarding tumor demographics and anatomical *** the limited number of reports on this condition,long-term follow-up is crucial to enhance our understanding of its *** For patients with adrenocortical oncocytoma,EUS-FNA can enables collection of preoperative tissue specimens leading to suitable treatment strategies.

关键词： Adrenocortical oncocytoma Non-functioning tumor Endoscopic ultrasound guided fine-needle aspiration Diagnosis Case report

Quantum Memory via Wigner Crystals of Polar Molecules

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Chinese Physics Letters 2011年第12期28卷 32-35页

作者： xue Peng Department of Physics Southeast UniversityNanjing 211189

Collective excitations of rotational and spin states of an ensemble of polar molecules as a candidate for a high-fidelity quantum memory are *** dipolar crystals are formed in the high-density limit of cold clouds of polar molecules under one-dimensional trapping *** lifetime of quantum memory is calculated by identifying the dominant decoherence mechanisms,and we estimate their effects on gate operations,when a molecular ensemble qubit is transferred to a superconducting microwave cavity.

关键词： ensemble quantum operations

Quantum Computing via Singlet-Triplet Spin Qubits in Nanowire Double Quantum Dots

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Chinese Physics Letters 2011年第7期28卷 31-34页

作者： xue Peng Department of Physics Southeast UniversityNanjing 211189

We propose a new structure for quantum computing via spin qubits with high *** spin qubit corresponds to two electrons in a nanowire double quantum dot,with the singlet and one of the triplets as the logical qubit *** entangling gate is effected by virtual charge dipole *** include noise to show the feasibility of this scheme under current experimental conditions.

关键词： conditions states quantum

Physiological-physical feature fusion for automatic voice spoofing detection

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Frontiers of Computer Science 2023年第2期17卷 157-166页

作者： Junxiao xue Hao ZHOU Research Institute of Artificial Intelligence Zhejiang LabHangzhou 311121China School of Cyber Science and Engineering Zhengzhou UniversityZhengzhou 450002China Henan Key Laboratory of Cyberspace Situation Awareness Zhengzhou 450000China

Biometric speech recognition systems are often subject to various spoofing attacks,the most common of which are speech synthesis and speech conversion *** spoofing attacks can cause the biometric speech recognition system to incorrectly accept these spoofing attacks,which can compromise the security of this *** have made many efforts to address this problem,and the existing studies have used the physical features of speech to identify spoofing ***,recent studies have shown that speech contains a large number of physiological features related to the human *** example,we can determine the speaker's gender,age,mouth shape,and other information by *** by the above researches,we propose a spoofing attack recognition method based on physiological-physical features *** method involves feature extraction,a densely connected convolutional neural network with squeeze and excitation block(SE-DenseNet),and feature fusion *** first extract physiological features in audio from a pretrained convolutional *** we use SE-DenseNet to extract physical *** a dense connection pattern has high parameter efficiency,and squeeze and excitation blocks can enhance the transmission of the ***,we integrate the two features into the classification network to identify the spoofing *** results on the ASVspoof 2019 data set show that our model is effective for voice spoofing *** the logical access scenario,our model improves the tandem decision cost function and equal error rate scores by 5%and 7%,respectively,compared to existing methods.

关键词： spoofing attacks SE-DenseNet physiological feature