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Accurate and broadband manipulations of harmonic amplitudes and phases to reach 256 QAM millimeter-wave wireless communications by time-domain digital coding metasurface

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National Science Review 2022年第1期9卷 36-46页

作者： Ming Zheng Chen Wankai Tang jun Yan Dai jun Chen ke Lei Zhang Cheng Zhang Jin Yang Lianlin Li Qiang Cheng shi Jin Tie jun Cui Institute of Electromagnetic Space Southeast University State key Laboratory of Terahertz and Millimeter Waves City University of Hong Kong State key Laboratory of Advanced Optical Communication Systems and Networks Department of Electronics Peking University National Mobile Communications Research Laboratory Southeast University State key Laboratory of Millimeter Waves Southeast University Center of Intelligent Metamaterials Pazhou Laboratory

We propose a theoretical mechanism and new coding strategy to realize extremely accurate manipulations of nonlinear electromagnetic harmonics in ultrawide frequency band based on a time-domain digital coding metasurface(TDCM).Using the proposed mechanism and coding strategy,we design and fabricate a millimeter-wave(mmWave) TDCM,which is composed of reprogrammable meta-atoms embedded with positive-intrinsic-negative *** controlling the duty ratios and time delays of the digital coding sequences loaded on a TDCM,experimental results show that both amplitudes and phases of different harmonics can be engineered at will simultaneously and precisely in broad frequency band from 22 to33 GHz,even when the coding states are imperfect,which is in good agreement with theoretical *** on the fabricated high-performance TDCM,we further propose and experimentally realize a large-capacity mmWave wireless communication system,where 256 quadrature amplitude modulation,along with other schemes,is *** new wireless communication system has a much simpler architecture than the currently used mmWave wireless systems,and hence can significantly reduce the hardware *** believe that the proposed method and system architecture can find vast application in future mmWave and terahertz-wave wireless communication and radar systems.

关键词： metasurface time-domain digital coding accurate and broadband harmonic control 256 QAM millimeter-wave wireless communications

After announced carbon neutrality targets,more homework ahead for research

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Advances in Climate Change Research 2022年第2期13卷 157-158页

作者： ke-jun JIANG Energy Research Institute Beijing 100038China

By January 2022,more than 130 countries announced their carbon neutrality target by 2050 or before 2060,with more than 80%of global emissions,making it possible to achieve the Paris Agreement *** on the IEA(2021),COP26 climate pledges could help limit global warming to 1.8℃,but implementing them will be the *** is a big change by looking back the history of human being's action on climate change.

关键词： neutral looking carbon

基于微滴式数字PCR检测牛病毒性腹泻病毒方法的建立及初步应用

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农业生物技术学报 2025年第1期33卷 190-199页

作者：刘芯怡李丹秦刚陈俊贞付强史慧君新疆农业大学动物医学学院新疆草食动物新药研究与创制重点实验室天康生物制药有限公司新疆巴楚县畜牧兽医站中国农业科学院西部农业研究中心

牛病毒性腹泻病毒(Bovine viral diarrhea virus, BVDV)是引起犊牛(Bos sp.)病毒性腹泻的主要病原之一，导致犊牛免疫力降低，患病率和死亡率升高。目前对BVDV常用的检测方法存在灵敏度较低、容易出现假阳性等状况。本研究基于微滴式数... 详细信息

牛病毒性腹泻病毒(Bovine viral diarrhea virus, BVDV)是引起犊牛(Bos sp.)病毒性腹泻的主要病原之一，导致犊牛免疫力降低，患病率和死亡率升高。目前对BVDV常用的检测方法存在灵敏度较低、容易出现假阳性等状况。本研究基于微滴式数字PCR(droplet digital PCR, ddPCR)技术，建立BVDV精准检测技术。首先针对BVDV 5'UTR基因保守序列区域设计引物和探针，合成BVDV 5'UTR基因并构建质粒标准品。使用BVDV质粒标准品分别建立实时荧光定量PCR(real-time quantitative PCR, qPCR)和ddPCR检测方法，并优化其反应参数和条件，分析其灵敏度、特异性和重复性，并进行了临床应用。结果显示，本研究建立的qPCR方法中，最佳引物和探针浓度分别为300和500 nmol/L，标准曲线呈良好的线性关系，最低检测下限为1×10～4 copies/μL，具有良好的特异性和重复性。建立的ddPCR方法中，最低检测下限为0.64 copies/μL，比qPCR灵敏性高15 625倍，该方法具有良好的特异性和重复性。临床检测了82份样品，ddPCR检出率为15.58%,qPCR检出率为14.63%。本研究建立的ddPCR方法比qPCR方法更加灵敏、高效、特异且重复性良好，为BVDV鉴别诊断提供了技术支持。

关键词：牛病毒性腹泻病毒(BVDV) 微滴式数字PCR(ddPCR) 实时荧光定量PCR(qPCR) 灵敏性特异性重复性

Natural orifice transluminal endoscopic wedge hepatic resection with a water-jet hybrid knife in a non-survival porcine model

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World Journal of Gastroenterology 2011年第7期17卷 926-931页

作者： Hong shi Sheng-jun Jiang Bin Li Deng-ke Fu Pei Xin Yong-Guang Wang Institute of Minimally Invasive Medicine Tongji University Shanghai200092 China Department of Minimally Invasive Sur-gery Beijing Chuiyangliu Hospital Beijing 100022 China

AIM: To explore the feasibility of a water-jet hybrid knife to facilitate wedge hepatic resection using a natural orifice transluminal endoscopic surgery (NOTES) approach in a non-survival porcine model. METHODS: The Erbe Jet2 water-jet system allows a needleless, tissue-selective hydro-dissection with a pre-selected pressure. Using this system, wedge hepatic resection was performed through three natural routes (trans-anal, trans-vaginal and trans-umbilical) in three female pigs weighing 35 kg under general anesthesia. Entry into the peritoneal cavity was via a 15-mm incision using a hook knife. The targeted liver segment was marked by an APC probe, followed by wedge hepatic resection performed using a water-jet hybrid knife with the aid of a 4-mm transparent distance soft cap mounted onto the tip of the endoscope for holding up the desired plane. The exposed vascular and ductal structures were clipped with Endoclips. Hemostasis was applied to the bleeding cut edges of the liver parenchyma by electrocautery. After the procedure, the incision site was left open, and the animal was euthanized followed by necropsy. RESULTS: Using the Erbe Jet2 water-jet system, trans-anal and trans-vaginal wedge hepatic resection was successfully performed in two pigs without laparoscopic assistance. Trans-umbilical attempt failed due to an unstable operating platform. The incision for peritoneal entry took 1 min, and about 2 h was spent on excision of the liver tissue. The intra-operative blood loss ranged from 100 to 250 mL. Microscopically, the hydro-dissections were relatively precise and gentle, preserving most vessels. CONCLUSION: The Erbe Jet2 water-jet system can safely accomplish non-anatomic wedge hepatic resection in NOTES, which deserves further studies to shorten the dissection time.

关键词： Natural orifice transluminal endoscopic surgery Hepatic resection Water-jet Hybrid knife Triangulation

Analysis of the dominant frequency in a subsonic compressor stator at near stall condition

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Chinese Science Bulletin 2014年第1期59卷 23-28页

作者： ke shi Song Fu School of Aerospace Tsinghua University

IDDES method was applied to investigate the highly unsteady flow in a subsonic compressor stator with very large hub clearance and high incidence *** blade loading variation frequency was found close to the rotating instability(RI)frequency f RI&333 Hz observed in the *** analysis of the flow physics shows that the loading variation is caused by the periodic swing of the large scale separated flow on the blade suction side *** breakdown of the leakage vortex has no significant dominant frequencies,thus cannot be the cause of RI in this compressor stator as normally ***,the vortex shedding and vortex breakdown due to shear layer instability at the outer edge of the blade suction surface separation region excite high frequency unsteadiness that can form the sources of noise.

关键词：压气机亚音速静子非定常流动频分状态失速优势频率

A novel dependency language model for information retrieval

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第6期8卷 871-882页

作者： CAI ke-ke BU Jia-jun CHEN Chun QIU Guang School of Computer Science and Technology Zhejiang University Hangzhou 310027 China

This paper explores the application of term dependency in information retrieval (IR) and proposes a novel dependency retrieval model. This retrieval model suggests an extension to the existing language modeling (LM) approach to IR by introducing dependency models for both query and document. Relevance between document and query is then evaluated by reference to the Kullback-Leibler divergence between their dependency models. This paper introduces a novel hybrid dependency structure, which allows integration of various forms of dependency within a single framework. A pseudo relevance feedback based method is also introduced for constructing query dependency model. The basic idea is to use query-relevant top-ranking sentences extracted from the top documents at retrieval time as the augmented representation of query, from which the relationships between query terms are identified. A Markov Random Field (MRF) based approach is presented to ensure the relevance of the extracted sentences, which utilizes the association features between query terms within a sentence to evaluate the relevance of each sentence. This dependency retrieval model was compared with other traditional retrieval models. Experiments indicated that it produces significant improvements in retrieval effectiveness.

关键词： Term dependency Language modeling (LM) Retrieval model Sentence retrieval

Empirical Research on the Application of a Structure-Based Software Reliability Model

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IEEE/CAA Journal of Automatica Sinica 2021年第6期8卷 1153-1162页

作者： Jie Zhang Yang Lu ke shi Chong Xu School of Computer and Information Anhui Normal UniversityWuhu 241003China School of Computer Science and Information Engineering Hefei University of TechnologyHefei 230601China

Reliability engineering implemented early in the development process has a significant impact on improving software *** can assist in the design of architecture and guide later testing,which is beyond the scope of traditional reliability analysis *** reliability models work for this,but most of them remain tested in only simulation case studies due to lack of actual *** we use software metrics for reliability modeling which are collected from source codes of post *** the proposed strategy,redundant metric elements are filtered out and the rest are aggregated to represent the module *** further propose a framework to automatically apply the module value and calculate overall reliability by introducing formal *** experimental results from an actual project show that reliability analysis at the design and development stage can be close to the validity of analysis at the test stage through reasonable application of metric *** study also demonstrates that the proposed methods have good applicability.

关键词： Algebraic method reliability evaluation software metrics software reliability

Effect of Top Slag Basicity on Quality of Steel Treated by Exothermic Agent SiFe and SiCaBa during Chemical Heating

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Journal of Iron and Steel Research International 2002年第1期9卷 12-15页

作者： WANG Hai-chuan ZHOU Yun WANG shi-jun YUE ke-xiang DONG Yuan-chi Anhui University of Technology

The effect of top slag basicity on quality of steel treated with SiFe and SiCaBa alloy as exothermic agent in chemical heating was *** experiments were carried out in MoSi_2 laboratory furnace with 0.2 kg molten steel for equilibrium test and 2 kg molten steel for simulation test *** results showed that the adjusting basicity of top slag with CaO is effective to prevent rephosphorization and resulphurization,and it is possible to dephosphorize and desulphurize and remove the inclusions from molten steel when basicity R of the top slag is adjusted to 2.0 — 3.10,and SiCaBa alloy is better than SiFe alloy in this relation.

关键词： chemical heating top slag basicity SiFe SiCaBa exothermic agent

Coordinated reduction of CO_(2) emissions and environmental impacts with integrated city-level LEAP and LCA method: A case study of Jinan, China

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Advances in Climate Change Research 2021年第6期12卷 848-857页

作者： CHEN Sha LIU Ying-Ying LIN Jin shi Xiao-Dan JIANG ke-jun ZHAO Guang-Lin Department of Environmental Science Key Laboratory of Beijing on Regional Air Pollution ControlBeijing University of TechnologyBeijing100124China Energy Research Institute Beijing100038China College of Engineer Swansea UniversitySwanseaSA18ENUnited Kingdom

The evaluation of the efficiency and feasibility of energy transition and air pollution control at the city level is one of the key points in addressing environmental problems and achieving the goals of CO_(2) emission reduction and carbon neutrality in China. In this study, an integrated method is developed on the basis of the Low Emissions Analysis Platform (LEAP) and life cycle assessment (LCA). The energy demands and environmental co-benefits in Jinan, one of the low-carbon city pilots in China, are quantitatively evaluated under three policy scenarios: low-carbon (LC) policy scenario, pollution control (PC) policy scenario, and deep-level cut of CO_(2) emissions (DCC) scenario from 2016 to 2050. From 2016 to 2030, the PC policies would be more powerful than the LC policies in terms of energy demand decrease. From 2030 to 2050, the LC policies would be more efficient than all the other policies. Promoting energy-saving buildings in the LC scenario would contribute to the continual decline in energy demands. In the DCC scenario, CO_(2), PM_(2.5), PM_(10), CO, NO_(X) and SO_(2) emissions would decline by more than 71.4% relative to the records in 2016. Global warming potential, human toxicity potential, photochemical ozone creation potential, particulate matter formation potential, and acidification potential would also decrease by 81.8%–88.5%. On the basis of the integrated city-level LEAP and LCA method, this study quantifies the various environmental impacts of urban decarbonization policies and provides science-based references for urban low-carbon transformation.

关键词： Coordinated emission reduction Environmental co-benefits LEAP-LCA Jinan