检索结果-南通市图书馆

The capillary pressure curves from upscaling interfacial and unsaturated flows in porous layers with vertical heterogeneity

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Theoretical & Applied Mechanics Letters 2023年第4期13卷 287-290页

作者： Zhong Zheng State Key Laboratory of Ocean Engineering School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China MOE Key Laboratory of Hydrodynamics School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China

We provide the capillary pressure curves p_(c)(s)as a function of the effective saturation s based on the theoretical framework of upscaling unsaturated flows in vertically heterogeneous porous layers proposed recently(Z.zheng,Journal of Fluid Mechanics,950,A17,2022).Based on the assumption of vertical gravitational-capillary equilibrium,the saturation distribution and profile shape of the invading fluid can be obtained by solving a nonlinear integral-differential equation.The capillary pressure curves p_(c)(s)can then be constructed by systematically varying the injection rate.Together with the relative permeability curves k_(rn)(s)that are already obtained.One can now provide quick estimates on the overall behaviours of interfacial and unsaturated flows in vertically-heterogeneous porous layers.

关键词： Flow upscaling Interfacial and unsaturated flow Wetting and capillary effects Porous layer Heterogeneity

On optimization of cooperative MIMO for underlaid secrecy Industrial Internet of Things

在线全文

学校读者我要写书评

暂无评论

Frontiers of Information Technology & Electronic Engineering 2023年第2期24卷 259-274页

作者： Xinyao WANG Xuyan BAO Yuzhen HUANG Zhong Zheng Zesong FEI School of Information and Electronics Beijing Institute of TechnologyBeijing100081China China Academy of Information and Communications Technology Beijing100191China Academy of Military Sciences of PLA Beijing100091China

In this paper,physical layer security techniques are investigated for cooperative multi-input multi-output(C-MIMO),which operates as an underlaid cognitive radio system that coexists with a primary user(PU).The underlaid secrecy paradigm is enabled by improving the secrecy rate towards the C-MIMO receiver and reducing the interference towards the PU.Such a communication model is especially suitable for implementing Industrial Internet of Things(IIoT)systems in the unlicensed spectrum,which can trade off spectral efficiency and information secrecy.To this end,we propose an eigenspace-adaptive precoding(EAP)method and formulate the secrecy rate optimization problem,which is subject to both the single device power constraint and the interference power constraint.This precoder design is enabled by decomposing the original optimization problem into eigenspace selection and power allocation sub-problems.Herein,the eigenvectors are adaptively selected by the transmitter according to the channel conditions of the underlaid users and the PUs.In addition,a simplified EAP method is proposed for large-dimensional C-MIMO transmission,exploiting the additional spatial degree of freedom for a low-complexity secrecy precoder design.Numerical results show that by transmitting signal and artificial noise in the properly selected eigenspace,C-MIMO can eliminate the secrecy outage and outperforms the fixed eigenspace precoding methods.Moreover,the proposed simplified EAP method for the large-dimensional C-MIMO can significantly improve the secrecy rate.

关键词： Cognitive radio network Physical layer security Cooperative multi-input multi-output(C-MIMO) Eigenspace-adaptive precoding Difference convex programming

Approximation Algorithms on k-Correlation Clustering

在线全文

学校读者我要写书评

暂无评论

Journal of the Operations Research Society of China 2023年第4期11卷 911-924页

作者： zhong-zheng Tang Zhuo Diao School of Science Beijing University of Posts and TelecommunicationsBeijing100876China School of Statistics and Mathematics Central University of Finance and EconomicsBeijing100081China

In this paper,we consider the k-correlation clustering problem.Given an edge-weighted graph G(V,E)where the edges are labeled either“+”(similar)or“−”(different)with nonnegative weights,we want to partition the nodes into at most k-clusters to maximize agreements—the total weights of“+”edges within clusters and“−”edges between clusters.This problem is NP-hard.We design an approximation algorithm with the approximation ratio{a,(2-k)a+k-1/k},where a is the weighted proportion of“+”edges in all edges.As a varies from 0 to 1,the approximation ratio varies from k-1/k to 1 and the minimum value is 1/2.

关键词： k-Correlation clusters Approximation algorithms Choosing the better of two solutions

Human-cyber-physical system for production and operation decision optimization in smart steel plants

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2022年第2期65卷 247-260页

作者： zheng zhong ZHANG KaiTian GAO XiaoQiang College of Materials Science and Engineering Chongqing UniversityChongqing 400045China College of Economics and Business Administration Chongqing UniversityChongqing 400045China

Based on the core developmental demands of smart steel manufacturing plants, this review analyzes the essential characteristics of the steel manufacturing process and its implications for production and operation decision optimization(PODO). A discussion on the potential application of technologies, including the Industrial Internet, big data, cloud computing, and 5 G, in the PODO of smart steel plants based on the Industry 4.0 intelligent manufacturing and human-cyber-physical system(HCPS) is also presented. An adaptive update conception for a new dual-level cyber system(for management control and unit operation) of a flatstructured HCPS for steel plants is proposed to eliminate issues such as the hierarchical structure of the cyber system, the occurrence of data islands, and weak intelligence in PODO ability. Additionally, the review provided an in-depth analysis of the closed-loop decision logic of a dual-level HCPS. The critical technologies required for developing the HCPS model include data platforms and their associated application technologies, intelligent modeling, human-machine collaboration, and platform-based integration. Finally, suggestions are proposed to develop smart steel plants, including concept renewal, technological integration,and talent training.

关键词： HCPS smart steel plants PODO management control unit operation

Comparison of intracytoplasmic sperm injection(ICSI)outcomes in infertile men with spermatogenic impairment of differing severity

在线全文

学校读者我要写书评

暂无评论

Asian Journal of Andrology 2022年第3期24卷 299-304页

作者： Ping Ping Zhong Zheng Yi Ma Sha-Sha Zou Xiang-Feng Chen Center for Reproductive Medicine Ren Ji HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200135China Shanghai Key Laboratory for Assisted Reproduction and Reproductive Genetics Shanghai 200135China Shanghai Human Sperm Bank Shanghai 200135China

The extent of spermatogenic impairment on intracytoplasmic sperm injection(ICSI)outcomes and the risk of major birth defects have been little assessed.In this study,we evaluated the relationship between various spermatogenic conditions,sperm origin on ICSI outcomes,and major birth defects.A total of 934 infertile men attending the Center for Reproductive Medicine of Ren Ji Hospital(Shanghai,China)were classified into six groups:nonobstructive azoospermia(NOA;n=84),extremely severe oligozoospermia(esOZ;n=163),severe oligozoospermia(sOZ,n=174),mild oligozoospermia(mOZ;n=148),obstructive azoospermia(OAZ;n=155),and normozoospermia(NZ;n=210).Rates of fertilization,embryo cleavage,high-quality embryos,implantation,biochemical and clinical pregnancies,abortion,delivery,newborns,as well as major birth malformations,and other newborn outcomes were analyzed and compared among groups.The NOA group showed a statistically lower fertilization rate(68.2%vs esOZ 77.3%,sOZ 78.0%,mOZ 73.8%,OAZ 76.6%,and NZ 79.3%,all P<0.05),but a significantly higher implantation rate(37.8%)than the groups esOZ(30.1%),sOZ(30.4%),mOZ(32.6%),and OAZ(31.0%)(all P<0.05),which was similar to that of Group NZ(38.4%).However,there were no statistically significant differences in rates of embryo cleavage,high-quality embryos,biochemical and clinical pregnancies,abortions,deliveries,major birth malformations,and other newborn outcomes in the six groups.The results showed that NOA only negatively affects some embryological outcomes such as fertilization rate.There was no evidence of differences in other embryological and clinical outcomes with respect to sperm source or spermatogenic status.Spermatogenic failure and sperm origins do not impinge on the clinical outcomes in ICSI treatment.

关键词： intracytoplasmic sperm injection nonobstructive azoospermia normozoospermia obstructive azoospermia oligozoospermia

PINK1 is involved in determining the cellular autophagic hierarchy

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China(Life Sciences) 2024年第5期67卷 1087-1088页

作者： Zhuchen Zhou zhong Chen Yanrong zheng Key Laboratory of Neuropharmacology and Translational Medicine of Zhejiang Province School of Pharmaceutical SciencesZhejiang Chinese Medical UniversityHangzhou 311402China

The protein PINK1 plays a crucial role in the regulation of the cellular autophagic hierarchy.Autophagy,a highly conserved biological process,serves as a mechanism for the degradation of intracellular components by lysosomes.Autophagosomes play a pivotal role in this process by selectively sequestering specific targets,including damaged organelles,protein aggregates,and pathogens.

关键词： PINK1 determining hierarchy

Explosive eye injuries: characteristics, traumatic mechanisms, and prognostic factors for poor visual outcomes

在线全文

学校读者我要写书评

暂无评论

Military Medical Research 2023年第6期10卷 751-762页

作者： Ying Zhang Xin Kang Qiong Wu Zhong Zheng Jun Ying Mao-Nian Zhang Senior Department of Ophthalmology the Third Medical Center of Chinese PLA General HospitalBeijing 100039China Department of Ophthalmol‑ogy the First Medical Center of Chinese PLA General HospitalBeijing 100853China Medical Security Center Chinese PLA General HospitalBeijing 100853China Information Center Logistics Support DepartmentCentral Military CommissionBeijing 100842China Information Management Department Chinese PLA General HospitalBeijing 100853China

Background: Explosions can produce blast waves, high-speed medium, thermal radiation, and chemical spatter,leading to complex and compound eye injuries. However, few studies have comprehensively investigated the clinical features of different eye injury types or possible risk factors for poor prognosis.Methods: We retrospectively reviewed all consecutive records of explosive eye injuries(1449 eyes in 1115 inpatients)in 14 tertiary referral hospitals in China over 12 years(between January 1, 2008 and December 31, 2019). Data on demographics, eye injury types, ocular findings, treatments, and factors affecting visual prognosis were extracted from a standardized database of eye injuries and statistically analyzed.Results: Mechanical ocular trauma accounted for 94.00% of explosion-related eye injuries, among which intraocular foreign bodies(IOFBs) resulted in 55.17% of open globe injuries(OGIs) and contusion caused 60.22% of close globe injuries(CGIs). Proliferative vitreous retinopathy(PVR) was more common in perforating(47.06%) and IOFB(26.84%)than in penetrating(8.79%) injuries, and more common with laceration(24.25%) than rupture(9.22%, P<0.01).However, no difference was observed between rupture and contusion. Ultimately, 9.59% of eyes were removed and the final vision was ≤4/200 in 45.82% of patients. Poor presenting vision [odds ratio(OR)=5.789], full-thickness laceration of the eyeball ≥5 mm(OR=3.665), vitreous hemorrhage(OR=3.474), IOFB(OR=3.510), non-mechanical eye injury(NMEI, OR=2.622), rupture(OR=2.362), traumatic optic neuropathy(OR=2.102), retinal detachment(RD,OR=2.033), endophthalmitis(OR=3.281), contusion(OR=1.679), ciliary body detachment(OR=6.592), zone Ⅲ OGI(OR=1.940), and PVR(OR=1.615) were significant negative predictors for poor visual outcomes(P<0.05).Conclusions: Explosion ocular trauma has complex mechanisms, with multiple eyes involved and poor prognosis. In lethal level Ⅰ explosion injuries, eyeball rupture is a serious condition, whereas contusion is more likely to improve. In level Ⅱ inj

关键词： Explosion-related eye injury Mechanical ocular trauma Visual outcome Risk factor

Spreading-rate dependence of hydroacoustic and teleseismic seismicity of ridge-transform systems:East Pacific Rise,Galapagos Ridge,and Mid-Atlantic Ridge

在线全文

学校读者我要写书评

暂无评论

Acta Oceanologica Sinica 2022年第5期41卷 124-135页

作者： Tingting zheng Jian Lin Qiu zhong Key Laboratory of Ocean and Marginal Sea Geology South China Sea Institute of OceanologyInnovation Academy of South China Sea Ecology and Environmental EngineeringChinese Academy of SciencesGuangzhou510301China Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou) Guangzhou511458China China-Pakistan Joint Research Center on Earth Sciences Chinese Academy of Science-Higher Education Commission(Pakistan)Islamabad45320Pakistan Department of Ocean Science and Engineering Southern University of Science and TechnologyShenzhen518055China Department of Geology and Geophysics Woods Hole Oceanographic InstitutionFalmouthWoods HoleMA02543USA

Seismicity in ocean ridge-transform systems reveals fundamental processes of mid-ocean ridges,while comparisons of seismicity in different oceans remain rare due to a lack of detection of small events.From 1996 to 2003,the Pacific Marine Environmental Laboratory of the National Oceanic and Atmospheric Administration(NOAA/PMEL)deployed several hydrophones in the eastern Pacific Ocean and the northern Atlantic Ocean.These hydrophones recorded earthquakes with small magnitudes,providing us with opportunities to study the seismic characteristics of ridge-transform systems at different spreading rates and make further comparisons of their differences.This study comparatively analyzed hydroacoustic and teleseismic data recorded on the fast-spreading East Pacific Rise(EPR,10°S to 12°N),intermediate-spreading Galapagos Ridge(103°W to 80°W),and slow-spreading Mid-Atlantic Ridge(MAR,15°N to 37°N).We present a systematic study of the spatial and temporal distribution of events,aftershock seismicity,and possible triggering mechanisms of aftershock sequences.Our analysis yields the following conclusions.(1)From the hydroacoustic data,the EPR transform faults had the highest average seismicity rate among the three regions.(2)Along-ridge event distributions show that a high number of earthquakes were concentrated on the EPR,while they became dispersed on the GR and fewer and more scattered on the MAR,reflecting that the different tectonic origins were closely correlated with the spreading rate.(3)Analysis from mainshock-aftershock sequences shows no significant differences in the aftershock decay rate among the three regions.(4)Multiple types of aftershock triggering models were inferred from Coulomb stress changes:strike-slip mainshocks triggered strike-slip aftershocks and normal faulting aftershocks,and normal faulting mainshocks triggered normal faulting aftershocks.Although these results are case studies,they may be applicable to other ocean ridge-transform systems in future investigations.Our results provide important new

关键词： East Pacific Rise Galapagos Ridge Mid-Atlantic Ridge hydroacoustic and teleseismic seismicity ridge-transform system

在线全文

学校读者我要写书评

暂无评论

郑启仲运用升降散治疗儿科疾病经验

中华中医药杂志 2014年第6期29卷 1864-1866页

作者：郑宏郑攀郑启仲河南中医学院第一附属医院儿科医院郑州450000 河南中医学院郑州450000 河南中医学院第一附属医院国医堂郑州450000

升降散出自杨栗山《伤寒瘟疫条辨》,原为治温疫的首要方剂,郑启仲教授运用升降散化裁治疗儿科多种疾病每获良效。文章通过整理郑启仲教授运用升降散治疗儿科疾病的验案,揭示其紧扣"气机失调、升降失常"的病机,擅于运用升降散治疗扁桃体... 详细信息

升降散出自杨栗山《伤寒瘟疫条辨》,原为治温疫的首要方剂,郑启仲教授运用升降散化裁治疗儿科多种疾病每获良效。文章通过整理郑启仲教授运用升降散治疗儿科疾病的验案,揭示其紧扣"气机失调、升降失常"的病机,擅于运用升降散治疗扁桃体炎、肺炎、过敏性紫癜、抽动症等的经验,体现了"异病同治"的原则,对于研究升降散的组方奥妙、证治范围及适应证候均有参考价值。

关键词：升降散儿科疾病郑启仲名医经验