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自成像魏格纳函数分析

光子学报 2007年第12期36卷 2325-2328页

作者：吕岑陕西科技大学电气与信息工程学院光电子系西安710021

在空域-频域空间,基于魏格纳变换和魏格纳分布函数,分析讨论了一维物体的自成像及其形成过程.从成像过程中各衍射频谱分量的光程差,给出了Talbot效应和Montgomery效应的统一解释.对于周期物的Talbot效应,得到了用杨氏双缝干涉解释自成... 详细信息

在空域-频域空间,基于魏格纳变换和魏格纳分布函数,分析讨论了一维物体的自成像及其形成过程.从成像过程中各衍射频谱分量的光程差,给出了Talbot效应和Montgomery效应的统一解释.对于周期物的Talbot效应,得到了用杨氏双缝干涉解释自成像现象的理论依据.周期物的自成像是物平面上间距为两倍周期、光程差为波长的整数平方倍的各衍射频谱分量同相相干迭加的结果.Montgomery效应是物平面上间距为抛物线关系、光程差为波长整数倍的各衍射频谱分量同相相干迭加的结果.

关键词：物理光学自成像 Talbot效应魏格纳函数 Montgomery效应

An overview on GNSS carrier-phase time transfer research

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Science China(Technological Sciences) 2020年第4期63卷 589-596页

作者： ZHANG Ming lü JinHu BAI ZhengDong JIANG ZhiQi CHEN BoBo The Key laboratory of Systems and Control Institute o f Systems ScienceAcademy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China Institute of Geomatics of Tsinghua university Beijing 100084China Management and Department of Energy and Resources Engineering College of EngineeringPeking UniversityBeijing 100871China

Global navigation satellite system(GNSS)carrier phase observations are two orders of higher accuracy than pseudo-range observations,and they are less affected by multipath *** a result,the time transfer accuracy can reach 0.1 ns,and the frequency transfer stability can reach 1×10^-15 with carrier phase(CP)method,therefore CP method is considered the most accurate and promising time transfer *** focus of this paper is to present a comprehensive summary of CP method,with specific attention directed toward day-boundary clock jump,ambiguity resolution(AR),multi-system time transfer and real-time time ***-boundary clock jump is essentially caused by pseudo-range *** approaches were proposed to solve the problem,such as continuously processing strategy,sliding batch and bidirectional filtering methods which were compared in this ***,researches on AR in CP method were *** scholars attempted to fix the single-difference ambiguities to improve the time transfer result,however,owing to the uncalibrated phase delay(uPD)was not considered,the current studies on AR in CP method were still ***,because four GNSS systems could be used for time-transfer currently,which was helpful to increase the accuracy and reliability,the researches on multi-system time transfer were ***’s more,real-time time transfer attracted more attention nowadays,the preliminary research results were presented.

关键词： carrier phase(CP) time transfer day-boundary clock jump ambiguity resolution(AR) multi-system time transfer real-time time transfer

基于分布式密钥生成方法的RSA可验证签名分享设计(英文)

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软件学报 2007年第1期18卷 168-176页

作者：吕克伟信息安全国家重点实验室(中国科学院研究生院) 北京100049

主要研究由Franklin和Reiter提出的可验证签名分享(VΣS).它可以允许一个签名的接受者在n个代理之间分享该签名,使得代理者的一些子集以后可以重构该签名.利用安全的分布式密钥生成方式、门限密码系统以及可验证秘密分享,给出了一个RSAV... 详细信息

主要研究由Franklin和Reiter提出的可验证签名分享(VΣS).它可以允许一个签名的接受者在n个代理之间分享该签名,使得代理者的一些子集以后可以重构该签名.利用安全的分布式密钥生成方式、门限密码系统以及可验证秘密分享,给出了一个RSAVΣS的新协议.该协议是有效的、可证安全的,并且可以容忍至多一半代理的恶意行为.

关键词：签名可验证秘密分享协议门限密码系统

Chronic intestinal failure and short bowel syndrome in Crohn’s disease

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World Journal of Gastroenterology 2021年第24期27卷 3440-3465页

作者： Aysegül Aksan Karima Farrag Irina Blumenstein Oliver Schröder Axel.u Dignass Jürgen Stein Institute of Nutritional Sciences Justus-Liebig-UniversitätGiessen 35392Germany Department of Clinical Research Interdisziplinäres Crohn Colitis Centrum Rhein-MainFrankfurt am Main 60594Germany Department of Gastroenterology and Clinical Nutrition DGD Kliniken SachsenhausenTeaching Hospital of the JW Goethe UniversityFrankfurt am Main 60594Germany Department of Gastroenterology Hepatology and Clinical NutritionFirst Medical ClinicJW Goethe University HospitalFrankfurt am Main 60529Germany Department of MedicineⅠ Agaplesion Markus HospitalGoethe-UniversityFrankfurt am Main 60431Germany Institute of Pharmaceutical Chemistry JW Goethe University60438 Frankfurt am MainGermany

Chronic intestinal failure(CIF)is a rare but feared complication of Crohn’s *** on the remaining length of the small intestine,the affected intestinal segment,and the residual bowel function,CIF can result in a wide spectrum of symptoms,from single micronutrient malabsorption to complete intestinal *** of CIF has improved significantly in recent *** in home-based parenteral nutrition,in particular,have translated into increased survival and improved quality of ***,60%of patients are permanently reliant on parenteral *** results with new drugs such as teduglutide have added a new dimension to CIF *** outcomes of patients with CIF could be greatly improved by more effective prevention,understanding,and *** complex cases,the care of patients with CIF requires a multidisciplinary approach involving not only physicians but also dietitians and nurses to provide optimal intestinal rehabilitation,nutritional support,and an improved quality of ***,we summarize current literature on CIF and short bowel syndrome,encompassing epidemiology,pathophysiology,and advances in surgical and medical management,and elucidate advances in the understanding and therapy of CIF-related complications such as catheter-related bloodstream infections and intestinal failure-associated liver disease.

关键词： Chronic intestinal failure Short bowel syndrome Crohn's disease Inflammatory bowel disease Parenteral nutrition Intestinal failure-associated liver disease

Estimating Cumulative Treatment Effect under an Additive Hazards Model

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Journal of Systems Science & Complexity 2021年第2期34卷 724-734页

作者： lu Xiaoliang ZHANG Baoxue SuN l.uquan School of Statistics Capital University of Economics and BusinessBeijing 100070China Institute of Applied Mathematics Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China

In clinical and epidemiologic studies of time to event,the treatment effect is often of direct interest,and the treatment effect is not constant over *** this paper,the authors propose an estimator for the cumulative hazard difference under a stratified additive hazards *** asymptotic properties of the resulting estimator are established,and the finite-sample properties are examined through simulation *** application to a liver cirrhosis data set from the Copenhagen Study Group for liver Diseases is provided.

关键词： Additive hazards model cumulative hazards survival data time-dependent effect

Experimental Study of a Solar Thermal Incubator using a Phase-Change Material for Off-Grid use

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Open Journal of Applied Sciences 2024年第9期14卷 2471-2481页

作者： Yéouélé Thio Bati Ernest Boya Bi Ekoun Paul Magloire Koffi Prosper Gbaha laboratoire des Procds Industriels de Synthse de lEnvironnement et des Energies Nouvelles Institut National Polytechnique Flix Houphout-Boigny Yamoussoukro Cte dIvoire

The aim of this study was to provide a simple, easy-to-use incubation system for small-scale rural poultry farmers far from the electricity grid. To this end, a naturally ventilated solar thermal incubator was built and experimentally tested. A u-shaped evacuated tube collector and a wooden crate holding 50 eggs were used to build the solar thermal incubator. Water was used as the heat transfer fluid, and an EPCM was integrated into the incubation chamber for operation at night or when the sun was hidden. The heat generated by the solar collector and stored in the heat transfer fluid is transported to the incubation chamber by thermosiphon to heat the chamber. Temperature and humidity probes powered by a solar panel were placed at various locations to monitor the thermo-hygrometric efficiency of the incubation system. The incubator, heated by natural convection, proved to function normally, and the incubation chamber was maintained throughout the incubation period within a temperature range of 35.53˚C to 39.53˚C and relative humidity averaging 49.4% to 68.5%. The experiment was carried out by introducing 30 eggs and the results of the experimental study showed that the incubator’s efficiency was 87%. The performance tests gave a fertility rate of 93% and a hatching rate of 93%, i.e. 28 fertile eggs and 26 hatched eggs, respectively.

关键词： Solar Incubator Vacuum Tube Collector Encapsulated PCM Poultry Eggs

Probability to retrieve testicular spermatozoa in azoospermic patients

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Asian Journal of Andrology 2000年第3期2卷 199-205页

作者： H.-J.Glanden l.-C.Horn W.Dorschner u.Paasch J.Kratzsch Department of Dermatology/Andrology unit Department of Dermatology Department of PathologyDepartment of Dermatology Department of UrologyDepartment of Dermatology/Andrology UnitDepartment of Clinical Chemistry and Pathological Biochemistry University of Leipzig D-04103 Leipzig Germany

Aim: The degree of probability to retrieve spermatozoa from testicular tissue for intracytoplasmic sperm injection intooocytes is of interest for counselling of infertility patients. We investigated the relation of sperm retrieval to clinical dataand histological pattern in testicular biopsies from azoospermic patients. Methods: In 264 testicular biopsies from142 azoospermic patients, the testicular tissue was shredded to separate the spermatozoa, histological semi-thin sec-tions of which were then evaluated using Johnsen score. Results: The retrieval of spermatozoa correlated signifi-cantly (P ular volume (r = 0.49), the FSH concentration ( r = -0.66), the maximum score(r = 0.85) and the mean Johnsen score (r = 0.81). In the multivariate regression analysis the successful testicularsperm extraction showed the closest relationship to the maximum score. The testicular volume correlated significantlywith the mean Johnsen score ( r = 0.64, P l serum FSH concentration mainly with the maxi-mum score ( r = -0.77; P ly lower Johnsenscore compared to the patients who did not have any testicular disease in the past (3.7 ± 2.4 vs. 5.9 ± 2. 5; P lusion: In a limited range, the testicular volume and the FSH concentration in serum were related to theJohnsen score which correlated significantly with the sperm retrieval. The successful sperm retrieval can be expected inall azoospermic patients irrespective of the results of clinical examination. However, the probability of retrieval of sper-matozoa decreased significantly in patients with a FSH level > 18 u/l, tesficular volume l, mean Johnsen scoreum Johnsen score < 7.

关键词： sperm extraction testicular histology azoospermia male infertility follicle stimulating hormone

Quantitative Applications of Weather Satellite Data for Nowcasting:Progress and Challenges

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Journal of Meteorological Research 2024年第3期38卷 399-413页

作者： Jun lI Jing ZHENG Bo lI Min MIN Yanan l.u Chian-Yi l.u Zhenglong lI WPaul MENZEl Timothy J.SCHMIT John l.CINTINEO Scott lINDSTROM Scott BACHMEIER Yunheng XuE Yayu MA Di DI Han lIN Innovation Centre for Fengyun Meteorological Satellite(FYSIC) National Satellite Meteorological CentreChina Meteorological AdministrationBeijing100081China School of Atmospheric Sciences and Guangdong Province Key laboratory for Climate Change and Natural Disaster Studies Sun Yat-sen University and Southern Laboratory of Ocean Science and EngineeringZhuhai519082China Key laboratory of Geographic Information Science(Ministry of Education) East China Normal UniversityShanghai200241China Research Center for Environmental Changes Academia SinicaTaipei11529China Cooperative Institute for Meteorological Satellite Studies University of Wisconsin-MadisonMadisonWI53706USA Sensors and Calibration Branch STAR/NESDISMadisonWI53706USA Wuxi university Wuxi214105China School of Computer Science Chengdu University of Information TechnologyChengdu610225China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science&TechnologyNanjing210044China Key laboratory of Spatial Data Mining and Information Sharing of Ministry of Education National and Local Joint Engineering Research Center of Satellite Geospatial Information TechnologyFuzhou UniversityFuzhou350108China

Monitoring and predicting highly localized weather events over a very short-term period,typically ranging from minutes to a few hours,are very important for decision makers and public *** these events usually relies on radar observations through monitoring and *** advanced high-resolution imaging and sounding observations from weather satellites,nowcasting can be enhanced by combining radar,satellite,and other data,while quantitative applications of those data for nowcasting are advanced through using machine learning *** applications include monitoring the location,impact area,intensity,water vapor,atmospheric instability,precipitation,physical properties,and optical properties of the severe storm at different stages(pre-convection,initiation,development,and decaying),identification of storm types(wind,snow,hail,etc.),and predicting the occurrence and evolution of the *** observations can provide information on the environmental characteristics in the preconvection stage and are very useful for situational awareness and storm *** paper provides an overview of recent progress on quantitative applications of satellite data in nowcasting and its challenges,and future perspectives are also addressed and discussed.

关键词： weather satellite quantitative applications nowcasting pre-convection

Genome-wide identification and in silico gene expression analysis of the related to ABI3/VP1(RAV)transcription factor family in barley(Hordeum vulgare l.)

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BIOCEll 2021年第6期45卷 1673-1685页

作者： CÜNEYT uÇARlI Department of Molecular Biology and Genetics Istanbul UniversityIstanbul34134Turkey

RAV(Related to ABI3/VP1)transcription factors are unique members of the AP2-ERF superfamily with AP2 and B3 domains and play important roles in the regulation of seed germination,plant growth,and stress *** the study,7 RAV genes,named HvRAVs,were identified in barley based on the available genome *** five of the seven HvRAVs were located on chromosome 3,HvRAV5 and HvRAV7 were located on chromosome 1 and 4,*** of the predicted HvRAVs were intron-less,except HvRAV2,which had one *** proteins have shown basic,instable,and hydrophilic *** AP2 domain specific RAYD and WlG motifs were detected in all HvRAV ***,B3 repression domain,R/KlFGV,is also found in the C-terminal of *** were found to have stress-related cis-acting elements,including MYB,MYC,and ***2 was predicted to have no GARE motifs,TATCCCA or TAACAA(G/A),and *** drought conditions,the expression level of HvRAVs did not significantly change in a drought-sensitive barley genotype,whereas HvRAV5 and HvRAV7 were dramatically down-regulated in a drought-tolerant *** of HvRAV5 was also inhibited by ***7 was strongly induced by plant pathogen *** HvRAV6 was induced by exogenous gibberellin application and during the germination ***,HvRAV6 transcript was detected higher than other HvRAVs in all stress and control conditions as well as during *** silico analyses have shown that HvRAVs play a role in response to different abiotic and biotic stresses as well as in plant ***,the extensive biological roles of HvRAV genes in plant development and in response to abiotic and biotic stresses need further investigation.

关键词： Barley RAV AP2 domain B3 domain AP2/ERF family Cis-acting elements