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基于SFE参数化建模的汽车新平台开发
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作者 黄维 《汽车工艺师》 2024年第5期54-59,共6页
通过分析传统分车型研发模式,引出基于SFE参数化建模的汽车新平台开发。通过对标标杆车制订新平台刚度和模态性能指标,准备所需要的开发输入,详细介绍了新平台模型搭建过程和方法。根据性能目标对概念模型进行多方案性能提升工作,通过... 通过分析传统分车型研发模式,引出基于SFE参数化建模的汽车新平台开发。通过对标标杆车制订新平台刚度和模态性能指标,准备所需要的开发输入,详细介绍了新平台模型搭建过程和方法。根据性能目标对概念模型进行多方案性能提升工作,通过框架布置、断面尺寸调整、改变搭接方式等手段,在外造型冻结时刻同步使车身刚度模态性能达到目标值。先期结构性能材料一体化设计,大幅缩短开发周期,降低车型开发成本,提升性能指标。 展开更多
关键词 sfe参数化建模 先期设计 平台化开发 刚度 模态
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Trial application of the envelope method to the potential ambiguity problem
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作者 Li-Yuan Hu Yu-Shou Song 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第1期73-80,共8页
The optical potential ambiguity is a long-standing problem in the analysis of elastic scattering data.For a specific collid-ing system,ambiguous potential families can lead to different behaviors in the nearside and f... The optical potential ambiguity is a long-standing problem in the analysis of elastic scattering data.For a specific collid-ing system,ambiguous potential families can lead to different behaviors in the nearside and farside scattering components.By contrast,the envelope method can decompose the experimental data into two components with negative and positive deflection angles,respectively.Hence,a question arises as to whether the comparison between the calculated nearside(or farside)component and the derived positive-deflection-angle(or negative-deflection-angle)component can help analyze the potential ambiguity problem.In this study,we conducted a trial application of the envelope method to the potential ambiguity problem.The envelope method was improved by including uncertainties in the experimental data.The colliding systems of 16O+28Si at 215.2 MeV and 12C+12C at 1016 MeV were considered in the analyses.For each colliding system,the angular distribution experimental data were described nearly equally well by two potential sets,one of which is“surface transpar-ent”and the other is refractive.The calculated angular distributions were decomposed into nearside and farside scattering components.Using the improved envelope method,the experimental data were decomposed into the positive-deflection-angle and negative-deflection-angle components,which were then compared with the calculated nearside and farside components.The capability of the envelope method to analyze the potential ambiguities was also discussed. 展开更多
关键词 Elastic scattering Optical potential ambiguities envelope method Nearside/farside decomposition
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An envelope-based machine learning workflow for locating earthquakes in the southern Sichuan Basin
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作者 Kang Wang Jie Zhang +2 位作者 Ji Zhang Zhangyu Wang Ziyu Li 《Earthquake Research Advances》 CSCD 2024年第2期45-54,共10页
The development of machine learning technology enables more robust real-time earthquake monitoring through automated implementations. However, the application of machine learning to earthquake location problems faces ... The development of machine learning technology enables more robust real-time earthquake monitoring through automated implementations. However, the application of machine learning to earthquake location problems faces challenges in regions with limited available training data. To address the issues of sparse event distribution and inaccurate ground truth in historical seismic datasets, we expand the training dataset by using a large number of synthetic envelopes that closely resemble real data and build an earthquake location model named ENVloc. We propose an envelope-based machine learning workflow for simultaneously determining earthquake location and origin time. The method eliminates the need for phase picking and avoids the accumulation of location errors resulting from inaccurate picking results. In practical application, ENVloc is applied to several data intercepted at different starting points. We take the starting point of the time window corresponding to the highest prediction probability value as the origin time and save the predicted result as the earthquake location. We apply ENVloc to observed data acquired in the southern Sichuan Basin, China, between September 2018 and March 2019. The results show that the average difference with the catalog in latitude, longitude, depth, and origin time is 0.02°,0.02°, 2 km, and 1.25 s, respectively. These suggest that our envelope-based method provides an efficient and robust way to locate earthquakes without phase picking, and can be used in earthquake monitoring in near-real time. 展开更多
关键词 Waveform envelope Earthquake location Local seismicity Synthetic data Sparse stations
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A New Dynamic and Vertical Photovoltaic Integrated Building Envelope for High-Rise Glaze-Facade Buildings
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作者 Wuwei Zou Yan Wang +3 位作者 Enze Tian Jiaze Wei Jinqing Peng Jinhan Mo 《Engineering》 SCIE EI CAS CSCD 2024年第8期194-203,共10页
Substantially glazed facades are extensively used in contemporary high-rise buildings to achieve attractive architectural aesthetics.Inherent conflicts exist among architectural aesthetics,building energy consumption,... Substantially glazed facades are extensively used in contemporary high-rise buildings to achieve attractive architectural aesthetics.Inherent conflicts exist among architectural aesthetics,building energy consumption,and solar energy harvesting for glazed facades.In this study,we addressed these conflicts by introducing a new dynamic and vertical photovoltaic integrated building envelope(dvPVBE)that offers extraordinary flexibility with weather-responsive slat angles and blind positions,superior architectural aesthetics,and notable energy-saving potential.Three hierarchical control strategies were proposed for different scenarios of the dvPVBE:power generation priority(PGP),natural daylight priority(NDP),and energy-saving priority(ESP).Moreover,the PGP and ESP strategies were further analyzed in the simulation of a dvPVBE.An office room integrated with a dvPVBE was modeled using EnergyPlus.The influence of the dvPVBE in improving the building energy efficiency and corresponding optimal slat angles was investigated under the PGP and ESP control strategies.The results indicate that the application of dvPVBEs in Beijing can provide up to 131%of the annual energy demand of office rooms and significantly increase the annual net energy output by at least 226%compared with static photovoltaic(PV)blinds.The concept of this novel dvPVBE offers a viable approach by which the thermal load,daylight penetration,and energy generation can be effectively regulated. 展开更多
关键词 Weather-responsive facades Building energy efficiency Dynamic photovoltaic integrated building envelopes(PVBEs) Building-integrated photovoltaics(BIPVs)
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Hepatitis B surface antigen-negative but hepatitis B envelope antigen-positive false occult hepatitis B virus infection:A case report
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作者 Shu-Sheng Yang Fei Fu +4 位作者 Qian-Kun Xuan Zhou-Xiang Zhang Zhi-Jun Li Guang-Bo Li Xiao-Yu Yu 《World Journal of Hepatology》 2024年第10期1199-1207,共9页
BACKGROUND Occult hepatitis B infection(OBI)is characterized by the detection of hepatitis B virus(HBV)DNA in serum(usually HBV DNA<200 IU/mL)or the liver but negativity for hepatitis B surface antigen(HBsAg).The d... BACKGROUND Occult hepatitis B infection(OBI)is characterized by the detection of hepatitis B virus(HBV)DNA in serum(usually HBV DNA<200 IU/mL)or the liver but negativity for hepatitis B surface antigen(HBsAg).The diagnosis of OBI relies on the sensitivity of assays used in the detection of HBV DNA and HBsAg.HBsAg assays with inadequate sensitivity or inability to detect HBV S variants may lead to misdiagnosis of OBI in people with overt HBV infection.CASE SUMMARY We report a HBsAg-negative but hepatitis B envelope antigen-positive patient who had a significant HBV DNA level.The patient was initially diagnosed as having OBI.However,sequence analysis revealed a unique insertion of amino acid residues at positions 120-124 in the S protein,which affects the formation of a disulfide bond that is associated with the formation of a loop.It is well known that there is an overlap between the S protein and Pol protein.We found that this new insertion site occurred in polymerase/reverse transcriptase domain,indi-cating that this insertion might be involved in HBV pathogenicity.The patient was finally diagnosed with a false OBI.CONCLUSION An insertion of amino acid residues at positions 120-124 of the S protein affects the formation of immunodominant epitopes and results in negative HBsAg levels. 展开更多
关键词 Occult hepatitis B infection Hepatitis B virus Hepatitis B surface antigen Hepatitis B envelope antigen Immunodominant epitopes Case report
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Development of experimental study on coupled heat and moisture transfer in porous building envelope 被引量:2
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作者 陈国杰 刘向伟 +2 位作者 陈友明 郭兴国 邓永强 《Journal of Central South University》 SCIE EI CAS 2012年第3期669-674,共6页
A new facility was presented which can expediently and cheaply measure the transient moisture content profile in multi-layer porous building envelope.Then,a common multi-layer porous building envelope was provided,whi... A new facility was presented which can expediently and cheaply measure the transient moisture content profile in multi-layer porous building envelope.Then,a common multi-layer porous building envelope was provided,which was constructed by cement mortar-red brick-cement plaster.With this kind of building envelope installed in the south wall,a well-controlled air-conditioning room was set up in Changsha,which is one of typical zones of hot and humid climate in China.And experiments were carried out to investigate the temperature and moisture distribution in multi-layer building envelope in summer,both in sunny day and rainy day.The results show that,the temperature and humidity at the interface between the brick and cement mortar are seriously affected by the changes of outdoor temperature and humidity,and the relative humidity at this interface keeps more than 80% for a long-term,which can easily trigger the growth of mould.The temperature and humidity at the interface between the brick and cement plaster change a little,and they are affected by the changes of indoor temperature and humidity.The temperature and humidity at the interface of the wall whose interior surface is affixed with a foam plastic wallpaper are generally higher than those of the wall without wallpaper.The heat transfer and moisture transfer in the envelope are coupled strongly. 展开更多
关键词 coupled heat and moisture transfer transient moisture content multi-layer porous building envelope
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Hepatitis B virus envelope as a targeting gene transfer vector for hepatic cancer cells 被引量:1
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作者 Dejian Pan Weibing Wang +1 位作者 Donglin Wang Zhengtang Chen 《The Chinese-German Journal of Clinical Oncology》 CAS 2009年第8期447-452,共6页
Objective: The aim of the study was to observe the transfection efficacy of hepatitis B virus envelope (HBVE) and evaluate its ability as a gene transfer vector for liver cancer cells. Methods: To obtain HBVE, the... Objective: The aim of the study was to observe the transfection efficacy of hepatitis B virus envelope (HBVE) and evaluate its ability as a gene transfer vector for liver cancer cells. Methods: To obtain HBVE, the supematant fluid of HepG 2.2.15 cells was mixed with a PEG8000 solution for concentration and was inactivated by β-propiolactone. The acquired HBVE was used to pack plRES2-EGFP to test its package ability. Then, we examined its quantity and quality with ELISA, PCR, SDS-PAGE and electron microscopy. The plRES2-EGFP was packed with HBVE and obtained the product HBVE-GFP. The plRES2-EGFP was packed with liposome and obtained the product liposome-GFP. HBVE-GFP and liposome-GFP were used to transfer HepG 2 cells to study the transfection efficiency. HBVE-GFP was used to transfer HepG 2, A549, HeLa and FB cells to study the targeting ability. The green fluorescent protein (GFP) expression was observed under a fluorescent microscope. The rate of GFP positive cells was determined by flow cytometry. Results: 1. The acquired HBVE could retain the surface protein HBsAg + pre S1 + pre S2 and had no virus DNA. It had good package ability for plRES2-EGFP. 2. Transfection efficiency: The GFP could be observed in both the liposome group and HBVE group under the fluorescent microscope. But the HBVE group had a higher fluorescent intensity than liposome group. The transfection rate of liposome group was 49.97% + 2.37% while the HBVE group was 70.65% + 3.15% and the fluorescent intensity of the HBVE group was 3-4 times (P = 0.000) for liposome group with the determination of flow cytometry. 3. Targeting ability: The GFP could be observed in the four groups under the fluorescent microscope. The HepG 2 group had the highest fluorescent intensity among the four groups. The transfection rate of HepG 2 group was 71.35% + 0.03% which was highly expressed than other groups (P = 0.000) and the fluorescent intensity of the HepG 2 group was 2-3 times (P = 0.000) for the other 3 groups with the determination of flow cytometry. Conclusion: HBVE can be constructed successfully with the methods of PEG8000 and β-propiolactone from the supernatant fluid of HepG 22.15 cells. The HBVE can be a candidate gene transfer vector for liver cancer cells. 展开更多
关键词 hepatitis B virus envelope (HBVE) transfection efficacy targeting ability hepatic cancer gene transfer vector
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Pepper mild mottle virus coat protein interacts with pepper chloroplast outer envelope membrane protein OMP24 to inhibit antiviral immunity in plants 被引量:4
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作者 Kelei Han Hongying Zheng +11 位作者 Dankan Yan Huijie Zhou Zhaoxing Jia Yushan Zhai Jian Wu Yuwen Lu Guanwei Wu Shaofei Rao Jianping Chen Jiejun Peng Rende Qi Fei Yan 《Horticulture Research》 SCIE CSCD 2023年第5期16-28,共13页
Pepper mild mottle virus(PMMoV)is a devastating viral pathogen of pepper(Capsicum annuum)but it is unclear whether and how peppers protect against PMMoV infection.The expression of the chloroplast outer membrane prote... Pepper mild mottle virus(PMMoV)is a devastating viral pathogen of pepper(Capsicum annuum)but it is unclear whether and how peppers protect against PMMoV infection.The expression of the chloroplast outer membrane protein 24(OMP24)of C.annuum was upregulated under PMMoV infection and it interacted with PMMoV coat protein(CP).Silencing of OMP24 in either C.annuum or Nicotiana benthamiana facilitated PMMoV infection,whereas overexpression of N.benthamiana OMP24 in transgenic plants inhibited PMMoV infection.Both C.annuum OMP24(CaOMP24)and N.benthamiana OMP24(NbOMP24)localized to the chloroplast and have a moderately hydrophobic transmembrane domain that is necessary for their localization.Overexpression of CaOMP24 induced stromules,perinuclear chloroplast clustering,and accumulation of reactive oxygen species(ROS),the typical defense responses of chloroplasts transferring the retrograde signaling to the nucleus to regulate resistance genes.The expression of PR1 and PR2 was also upregulated significantly in plants overexpressing OMP24.Self-interaction of OMP24 was demonstrated and was required for OMP24-mediated plant defense.Interaction with PMMoV CP interfered with the self-interaction of OMP24 and impaired OMP24-induced stromules,perinuclear chloroplast clustering and ROS accumulation.The results demonstrate the defense function of OMP24 in pepper during viral infection and suggest a possible mechanism by which PMMoV CP modulates the plant defense to facilitate viral infection. 展开更多
关键词 outer IMMUNITY envelope
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Influence Factors of Heat Transfer of Unattached Rectangular Underground Engineering Envelope
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作者 袁艳平 吉洪湖 +2 位作者 宋保银 王健 王琴 《Journal of Shanghai Jiaotong university(Science)》 EI 2006年第4期518-524,共7页
Using a mathematical model of heat transfer of unattached underground engineering envelope, the calculation area was divided into 14 rectangular blocks according to the interzone temperature profile estimation (ITPE) ... Using a mathematical model of heat transfer of unattached underground engineering envelope, the calculation area was divided into 14 rectangular blocks according to the interzone temperature profile estimation (ITPE) technology, and the solutions were obtained for all the parts using the technique of variable separation. The Fourier coefficients are determined based on the continuity of the heat flux and boundary conditions, as a result, a system of linear equation group including 26N equations has been obtained. By changing the parameters, the influence of heat characteristics of envelope building material and soil, temperature of earth surface and heat transfer coefficient between air and wall on heat course of the envelope has been quantitatively analyzed. 展开更多
关键词 interzone temperature PROFILE estimation (ITPE) technique of variable separation BASEMENT envelope heat TRANsfeR
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Density-dependent carrier-envelope phase shift in attosecond pulse generation from relativistically oscillating mirrors 被引量:1
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作者 Rishat Zagidullin Stefan Tietze +2 位作者 Matt Zepf Jingwei Wang Sergey Rykovanov 《Matter and Radiation at Extremes》 SCIE EI CSCD 2023年第6期41-48,共8页
The carrier-envelope phase(CEP)φ_(0)is one of the key parameters in the generation of isolated attosecond pulses.In particular,“cosine”pulses(φ_(0)=0)are best suited for generation of single attosecond pulses in a... The carrier-envelope phase(CEP)φ_(0)is one of the key parameters in the generation of isolated attosecond pulses.In particular,“cosine”pulses(φ_(0)=0)are best suited for generation of single attosecond pulses in atomic media.Such“cosine”pulses have the peak of the most intense cycle aligned with the peak of the pulse envelope,and therefore have the highest contrast between the peak intensity and the neighboring cycles.In this paper,the dynamics of single attosecond pulse generation from a relativistically oscillating plasma mirror is investigated.We use an elementary analytical model as well as particle-in-cell simulations to study few-cycle attosecond pulses.We find that the phase of the field driving the surface oscillations depends on the plasma density and preplasma scale length.This leads us to a counterintuitive conclusion:for the case of normal incidence and a sharp plasma-vacuum boundary,the CEP required for the generation of a single attosecond pulse phase is closer toφ_(0)=π/2(a“sine”pulse),with the exact value depending on the plasma parameters. 展开更多
关键词 envelope OSCILLATING RELATIVISTIC
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Transfer of the zp3a gene results in changes in egg adhesiveness and buoyancy in transgenic zebrafish
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作者 Yu-Qing Cao Yong-Xin Wang +5 位作者 Yan Zhao Jia Zhang Xian He Ping Xie Jun Chen Yu-Hua Sun 《Zoological Research》 SCIE CAS CSCD 2023年第2期259-268,共10页
Reproductive strategies and spawning habits play key roles in the evolution of endemic East Asian cyprinids.However,the molecular mechanisms underlying the regulation of spawning habits are not well understood.We rece... Reproductive strategies and spawning habits play key roles in the evolution of endemic East Asian cyprinids.However,the molecular mechanisms underlying the regulation of spawning habits are not well understood.We recently identified zona pellucida(Zp) as the top differentially expressed protein between East Asian cyprinids that produce adhesive and semi-buoyant eggs,suggesting that Zp protein may play important roles in the regulation of egg type.In this work,we generated transgenic zebrafish in which oocyte-specific expression of zp genes from rare minnow(Gobiocypris rarus),an East Asian cyprinid laying adhesive eggs,was driven by a zebrafish zp3.2 gene promoter.We found that the transgenic eggs obtained partial adhesiveness and exhibited alteration in hydration and buoyancy.Abnormal metabolism of vitellogenin(VTG) may contribute to enhanced hydration and/or buoyancy.Our work shows that expression of the exogenous zp3a gene from an adhesiveegg producing fish is sufficient to induce changes in both egg adhesiveness and buoyancy in zebrafish,emphasizing the important role of zp genes in the regulation of spawning habits.Our results thus provide new insights into how endemic East Asian cyprinids may have adapted to the Yangtze river-lake system via changes in spawning habits. 展开更多
关键词 Zona pellucida protein ADHESIVE BUOYANCY HYDRATION Egg envelope
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Failure Envelopes of Single-Plate Rigid Helical Anchors for Floating Offshore Wind Turbine
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作者 CHEN Hong-zhen WANG Le +3 位作者 TIAN Ying-hui ZHANG Chun-hui SHEN Zhi-chao LIU Meng-meng 《China Ocean Engineering》 SCIE EI CSCD 2023年第6期1000-1010,共11页
Helical anchor is a kind of novel foundation for floating offshore wind turbines,which should be subjected to combined tensile loading caused by wind,wave and current.However,the research about the capacity of helical... Helical anchor is a kind of novel foundation for floating offshore wind turbines,which should be subjected to combined tensile loading caused by wind,wave and current.However,the research about the capacity of helical anchor was mainly examined under uniaxial loading and scarcely explored under combined loading.In this study,three-dimensional finite element limit analysis is adopted to assess the bearing capacities of single-plate rigid helical anchors with different ratios of helix to shaft diameter,D_(H)/D_(S) and embedment ratios L/D_(S).Result shows that the vertical,horizontal and moment bearing capacities increase with increasing D_(H)/D_(S) and L/D_(S).The normalized V-H failure envelopes expands with increasing L/D_(S),while the normalized V-M failure envelopes tend to contract with the increase of D_(H)/D_(S).With increasing D_(H)/D_(S) or decreasing L/D_(S),the normalized H-M failure envelopes expand when the horizontal and moment loading act in the same direction and contract when they act in the opposite direction.The effect of D_(H)/D_(S) and L/D_(S) on the shape of H-M failure envelope become insignificant when L/D_(S)≥4.A series of failure mechanisms under different loading conditions were observed and can be used to explain the trend.Besides,a series of approximate expressions were proposed to fit the uniaxial bearing capacities and the failure envelopes. 展开更多
关键词 helical anchors bearing capacity failure envelope CLAY
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Intelligent Digital Envelope for Distributed Cloud-Based Big Data Security
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作者 S.Prince Chelladurai T.Rajagopalan 《Computer Systems Science & Engineering》 SCIE EI 2023年第7期951-960,共10页
Cloud computing offers numerous web-based services.The adoption of many Cloud applications has been hindered by concerns about data security and privacy.Cloud service providers’access to private information raises mo... Cloud computing offers numerous web-based services.The adoption of many Cloud applications has been hindered by concerns about data security and privacy.Cloud service providers’access to private information raises more security issues.In addition,Cloud computing is incompatible with several industries,including finance and government.Public-key cryptography is frequently cited as a significant advancement in cryptography.In contrast,the Digital Envelope that will be used combines symmetric and asymmetric methods to secure sensitive data.This study aims to design a Digital Envelope for distributed Cloud-based large data security using public-key cryptography.Through strategic design,the hybrid Envelope model adequately supports enterprises delivering routine customer services via independent multi-sourced entities.Both the Cloud service provider and the consumer benefit from the proposed scheme since it results in more resilient and secure services.The suggested approach employs a secret version of the distributed equation to ensure the highest level of security and confidentiality for large amounts of data.Based on the proposed scheme,a Digital Envelope application is developed which prohibits Cloud service providers from directly accessing insufficient or encrypted data. 展开更多
关键词 Digital envelope Cloud computing big data ENCRYPTION DECRYPTION
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Envelope Method and More General New Global Structures of Solutions for Multi-dimensional Conservation Law
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作者 Gui-Qin Qiu Gao-Wei Cao +1 位作者 Xiao-Zhou Yang Yuan-An Zhao 《Communications on Applied Mathematics and Computation》 2023年第3期1180-1234,共55页
For the two-dimensional(2D)scalar conservation law,when the initial data contain two different constant states and the initial discontinuous curve is a general curve,then complex structures of wave interactions will b... For the two-dimensional(2D)scalar conservation law,when the initial data contain two different constant states and the initial discontinuous curve is a general curve,then complex structures of wave interactions will be generated.In this paper,by proposing and investigating the plus envelope,the minus envelope,and the mixed envelope of 2D non-selfsimilar rarefaction wave surfaces,we obtain and the prove the new structures and classifications of interactions between the 2D non-selfsimilar shock wave and the rarefaction wave.For the cases of the plus envelope and the minus envelope,we get and prove the necessary and sufficient criterion to judge these two envelopes and correspondingly get more general new structures of 2D solutions. 展开更多
关键词 Riemann problem Non-selfsimilar shock wave Non-selfsimilar rarefaction wave envelope Multi-dimensional conservation law
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Coherent Parameter Measurement Based on Partial Coherent Envelope Demodulation
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作者 Chaoze Zhang Laiyang Dang +3 位作者 Tianyu Guan Yuqin Mao Ligang Huang Tao Zhu 《Optics and Photonics Journal》 2023年第6期133-139,共7页
The key parameters of laser energy concentration and coherence can be characterized by laser linewidth, which determines the detection range, measurement resolution and signal-to-noise ratio of laser precision measure... The key parameters of laser energy concentration and coherence can be characterized by laser linewidth, which determines the detection range, measurement resolution and signal-to-noise ratio of laser precision measurement technology. Up to now, the laser linewidth is mainly measured by the energy distribution width in the frequency domain, but the coherence of the laser has not been measured or characterized directly. In this work, we propose the concept of coherent linewidth based on the coherent envelope of delayed self-heterodyne detection to directly characterize the time-frequency coherence of lasers. In the proof-of-concept experiment, we obtain the coherence coefficient through the Fourier transform of the partial coherence envelope, and then measure the coherence linewidth of the laser. The measured coherent linewidth is smaller than the traditional integral linewidth and larger than the intrinsic Lorentzian linewidth, indicating that the coherent linewidth is less affected by low-frequency 1/f noise. The concept of coherent linewidth proposed in this article can serve as a candidate method for directly characterizing the coherence of narrow linewidth lasers. . 展开更多
关键词 Laser Linewidth Coherent Linewidth Coherent envelope
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英科“绿林”荣登SFEO上海生产性服务业品牌价值榜
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作者 蒋红芳 《上海化工》 CAS 2023年第3期61-61,共1页
首届中国制造品牌发展论坛暨第九届中国品牌经济(上海)论坛于5月14日举行。会上,上海企业文化与品牌研究所与上海市工业经济联合会发布了“TBB中国品牌价值榜”、“TBB上海制造品牌价值榜”、“SFEO上海生产性服务业品牌价值榜”、“SFE... 首届中国制造品牌发展论坛暨第九届中国品牌经济(上海)论坛于5月14日举行。会上,上海企业文化与品牌研究所与上海市工业经济联合会发布了“TBB中国品牌价值榜”、“TBB上海制造品牌价值榜”、“SFEO上海生产性服务业品牌价值榜”、“SFEO上海企业品牌成长榜”等一批品牌价值榜。上海英科实业有限公司(简称“上海英科”)的“绿林”品牌荣登“SFEO上海生产性服务业品牌价值榜”,位列第53名。 展开更多
关键词 生产性服务业 品牌价值 品牌成长 文化与品牌 (上海) sfe TBB 绿林
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A Theory on Increasing the Heat Transfer Performance of Building Wall
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作者 Yu Zhang ShaoLei Sun 《Journal of Building Material Science》 2023年第1期49-54,共6页
The target of traditional thermal conductivity of wall research is the spatial distribution form.In these studies,the change of thermal conductivity with temperature is neglected.Meanwhile,case studies are always used... The target of traditional thermal conductivity of wall research is the spatial distribution form.In these studies,the change of thermal conductivity with temperature is neglected.Meanwhile,case studies are always used.This method needs large computation and it is hard to obtain the optimal result.In order to overcome the problems,a new approach has been put forward in this paper.Different from the traditional approach,the new approach solves an inverse prob­lem under the concept of passive ideal energy-saving buildings to obtain the optimal distribution of heat ability with temperature on an external wall.The result for a typical summer day shows the heat ability distribution of a wall in summer is a staircase.It is similar to the heat pipe.It is also found that the optimal heat transfer property of the exter­nal wall is closer to the heat pipe when its heat capacity per square meter(ρc_(p)L)is of extreme value.This study can provide guidance to researchers in building materials. 展开更多
关键词 Thermal conductivity Building envelope Passive room Inverse problem Nonlinear optimization
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考虑最小平均包络熵负荷分解的最优Bagging集成超短期多元负荷预测 被引量:3
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作者 姜飞 林政阳 +3 位作者 王文烨 王小明 奚振乾 郭祺 《中国电机工程学报》 EI CSCD 北大核心 2024年第5期1777-1788,I0009,共13页
多元负荷预测技术是保证综合能源系统(integrated energy system,IES)供需平衡与稳定运行的关键基石。但具有强随机性与波动性的IES负荷加剧了超短期多元负荷准确预测的难度。为此,提出考虑最小平均包络熵负荷分解的最优Bagging集成超... 多元负荷预测技术是保证综合能源系统(integrated energy system,IES)供需平衡与稳定运行的关键基石。但具有强随机性与波动性的IES负荷加剧了超短期多元负荷准确预测的难度。为此,提出考虑最小平均包络熵负荷分解的最优Bagging集成超短期多元负荷预测方法。构建基于最小平均包络熵的变分模态分解参数优化模型,将IES多元负荷分解为本征模态分量集合;基于统一信息系数法筛选多元负荷预测的日历、气象与负荷强相关特征;结合负荷本征模态分量集合、日历规则、气象环境与负荷数据,构建Bagging集成超短期多元负荷预测模型,并建立基于平均绝对百分比误差与决定系数的集成策略优化模型,进而得到最优集成策略与最终预测结果。以美国亚利桑那州立大学坦佩校区IES为对象展开仿真验证,结果表明,所提方法的电、热、冷负荷预测平均绝对百分比误差分别为1.9486%、2.0585%、2.5331%,相比其他预测方法具有更高准确率。 展开更多
关键词 多元负荷预测 综合能源系统 集成学习 海洋捕食者算法 包络熵
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基于fsQCA组态视角的我国医疗资源配置效率提升路径分析 被引量:4
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作者 李丽清 杨苏乐 +1 位作者 万里晗 卢祖洵 《中国全科医学》 北大核心 2024年第4期413-419,共7页
背景当前我国医疗资源配置区域失衡、公平性缺失问题仍然突出。党的“二十大”报告明确提出要“促进优质医疗资源扩容和区域均衡布局”。目的探究提升我国医疗资源配置效率的具体路径,为实现我国医疗资源合理且高效配置、促进基本公共... 背景当前我国医疗资源配置区域失衡、公平性缺失问题仍然突出。党的“二十大”报告明确提出要“促进优质医疗资源扩容和区域均衡布局”。目的探究提升我国医疗资源配置效率的具体路径,为实现我国医疗资源合理且高效配置、促进基本公共服务均等化提供科学参考。方法于2022年9月—2023年2月开展研究,数据源于《2021中国统计年鉴》《2021中国卫生健康统计年鉴》。将医疗卫生机构数、卫生技术人员数、床位数作为投入指标,以诊疗人次和入院人数为产出指标,通过数据包络分析(DEA)方法对我国2020年31个省份医疗资源配置效率进行测度;以医疗资源配置效率为结果变量,以卫生技术人员占比、每千人口床位数、出院者平均住院日、人均国内生产总值(GDP)、居民可支配收入、财政收入分权和医疗卫生财政预算支出占比为条件变量,运用模糊集定性比较分析(fsQCA)方法从组态视角探究内外部要素对医疗资源配置效率的协同影响机制,剖析高或非高水平医疗资源配置效率的条件组态,明确医疗资源高效率和低效率配置的多重路径。结果2020年我国31个省份医疗资源配置效率整体水平较高,均值为0.852,但省际存在较大差异。组态分析结果可知,医疗资源配置效率的提升是多因素共同作用的结果,共存在3种医疗资源高效率配置的路径。路径1:政府主导型驱动路径,以广西壮族自治区为典型案例。路径2:内外协调型驱动路径,以云南省和甘肃省为代表案例。路径3:均衡型驱动路径,代表案例主要有广东省、福建省和湖北省。非高医疗资源配置效率的路径也存在3条。路径1:政府制约型路径。路径2:经济-政府双重制约型路径,代表案例有黑龙江省和吉林省。路径3:内外制约型路径,典型案例有山西省和西藏自治区。结论内外部各要素及要素间的协同在良性互动过程中共同影响着医疗资源配置效率水平,需优化内外部环境,并对关键资源要素进行有效整合,以形成合力,促进区域医疗资源合理配置。 展开更多
关键词 资源配置 卫生保健公平提供 数据包络分析 模糊集定性比较分析 组态路径
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超临界流体萃取技术在化工生产中的应用
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作者 王淑敏 《聚酯工业》 CAS 2024年第6期89-91,共3页
文章先阐述了超临界流体萃取技术的相关概念,分析该技术的优势特点。在化工领域,超临界流体萃取技术被应用于天然色素、香精香料、生物活性物质、油脂、药物成分等多种化合物的提取和纯化,既能提高产品质量,又能减少环境污染和能源消耗... 文章先阐述了超临界流体萃取技术的相关概念,分析该技术的优势特点。在化工领域,超临界流体萃取技术被应用于天然色素、香精香料、生物活性物质、油脂、药物成分等多种化合物的提取和纯化,既能提高产品质量,又能减少环境污染和能源消耗,符合绿色化工和可持续发展的理念。并进一步分析了超临界流体萃取技术在化工生产中的具体应用,展现出该技术强大的实用性和发展潜力。 展开更多
关键词 超临界流体萃取技术 超临界流体 sfe
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