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A novel approach to public-coin concurrent zero-knowledge and applications on resettable security
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作者 Zhenbin YAN Yi DENG 《中国科学:信息科学(英文版)》 SCIE EI CSCD 2019年第3期127-140,共14页
Canetti,Lin and Paneth in TCC 2013 showed a O(log^1+εn)rounds public-coin concurrent zeroknowledge argument system(CZK)based on the existence of collision resistant hash functions,which is currently known as round op... Canetti,Lin and Paneth in TCC 2013 showed a O(log^1+εn)rounds public-coin concurrent zeroknowledge argument system(CZK)based on the existence of collision resistant hash functions,which is currently known as round optimal public-coin CZK from standard assumptions.In this paper,we further address this problem and present an alternative construction of public-coin CZK argument system with succinct slot.The key technique involves a new variant of Earak's non-black-box simulate approach.In particular,the original protocol uses n commitments in each slot,while our construction uses one commitment in each slot.Through our simulation techniques,the simulator recovers any previous state needed for the probabilistically checkable proof(PCP)from the current committed state,which,in our view,may be of independent interest.Furthermore,the public-coin CZK argument system can be transformed into a resettable security protocol based on the one way functions assumption.Therefore,we present a new construction of the simultaneous resettable zero-knowledge argument system. 展开更多
关键词 ZERO-KNOWLEDGE CONCURRENT ZERO-KNOWLEDGE resettable ZERO-KNOWLEDGE CONCURRENT secure COMPUTATION COMPUTATIONAL COMPLEXITY
Synchronous resection of esophageal cancer and other organ malignancies:A systematic review 预览
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作者 Dimitrios Papaconstantinou Diamantis I Tsilimigras +7 位作者 Dimitrios Moris Adamantios Michalinos Aikaterini Mastoraki Efstratia Mpaili Natasha Hasemaki Anargyros Bakopoulos Dimitrios Filippou Dimitrios Schizas 《世界胃肠病学杂志:英文版》 SCIE CAS 2019年第26期3438-3449,共12页
BACKGROUND Neoplasms arising in the esophagus may coexist with other solid organ or gastrointestinal tract neoplasms in 6%to 15%of patients.Resection of both tumors synchronously or in a staged procedure provides the ... BACKGROUND Neoplasms arising in the esophagus may coexist with other solid organ or gastrointestinal tract neoplasms in 6%to 15%of patients.Resection of both tumors synchronously or in a staged procedure provides the best chances for long-term survival.Synchronous resection of both esophageal and second primary malignancy may be feasible in a subset of patients;however,literature on this topic remains rather scarce.AIM To analyze the operative techniques employed in esophageal resections combined with gastric,pancreatic,lung,colorectal,kidney and liver resections and define postoperative outcomes in each case.METHODS We conducted a systematic review according to PRISMA guidelines.We searched the Medline database for cases of patients with esophageal tumors coexisting with a second primary tumor located in another organ that underwent synchronous resection of both neoplasms.All English language articles deemed eligible for inclusion were accessed in full text.Exclusion criteria included:(1)Hematological malignancies;(2)Head/neck/pharyngeal neoplasms;(3)Second primary neoplasms in the esophagus or the gastroesophageal junction;(4)Second primary neoplasms not surgically excised;and(5)Preclinical studies.Data regarding the operative strategy employed,perioperative outcomes and longterm outcomes were extracted and analyzed using descriptive statistics.RESULTS The systematic literature search yielded 23 eligible studies incorporating a total of 117 patients.Of these patients,71%had a second primary neoplasm in the stomach.Those who underwent total gastrectomy had a reconstruction using either a colonic(n=23)or a jejunal(n=3)conduit while for those who underwent gastric preserving resections(i.e.,non-anatomic/wedge/distal gastrectomies)a conventional gastric pull-up was employed.Likewise,in cases of patients who underwent esophagectomy combined with pancreaticoduodenectomy(15%of the cohort),the decision to preserve part of the stomach or not dictated the reconstruction method(whether by a gastric pullup or a colonic/jej 展开更多
关键词 ESOPHAGECTOMY Esophageal neoplasm Second PRIMARY Multiple PRIMARY CONCURRENT neoplasms Management
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经皮肾镜碎石术联合顺行和逆行输尿管软镜治疗复杂性肾结石的临床研究 预览
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作者 李晶 邓骞 +3 位作者 刘全海 屈卫星 管振峰 程永毅 《海南医学》 CAS 2019年第11期1388-1390,共3页
目的比较单通道同期经皮肾镜联合顺行输尿管软镜及经尿道逆行输尿管软镜治疗复杂性肾结石的可行性及临床效果。方法回顾性分析2014年10月至2017年10月陕西省人民医院泌尿外科收治的84例复杂性肾结石患者的临床诊治资料,所有患者均给予... 目的比较单通道同期经皮肾镜联合顺行输尿管软镜及经尿道逆行输尿管软镜治疗复杂性肾结石的可行性及临床效果。方法回顾性分析2014年10月至2017年10月陕西省人民医院泌尿外科收治的84例复杂性肾结石患者的临床诊治资料,所有患者均给予单通道微创经皮肾镜联合顺行或逆行输尿管软镜治疗,其中行顺行手术44例(顺行组),逆行手术40例(逆行组),比较两组患者的手术时间、住院时间、结石清除率以及术后并发症的差异。结果顺行组患者的手术时间为(119.2±30.2) min,短于逆行组的(151.7±47.5) min,一期结石清除率为70.5%,低于逆行组的90.0%,差异均有统计学意义(P<0.05);顺行组和逆行组患者的住院时间分别为(7.5±2.0) d、(8.1±3.1) d,血红蛋白变化值分别(15.3±4.6) g/L和(14.8±4.0) g/L,手术并发症发生率分别为15.9%和15.0%,差异均无统计学意义(P>0.05);顺行组患者的住院费用为(2.5±0.6)万元,低于逆行组的(2.9±0.8)万元,差异有统计学意义(P<0.05)。结论对于复杂性结石,单通道同期微通道经皮肾镜联合输尿管软镜治疗是安全有效的。经皮肾镜联合顺行输尿管软镜治疗复杂性肾结石较为直接且费用较低,而联合逆行输尿管软镜治疗复杂性肾结石更为有效,但手术时间较长和费用较高,应根据患者具体情况决定手术方式。 展开更多
关键词 微创经皮肾镜取石术 输尿管软镜术 复杂性肾结石 同期 单通道
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面向国产平台的程序并发性能分析技术 预览
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作者 王立杰 胡先浪 张大方 《计算机系统应用》 2019年第6期100-104,共5页
随着国产处理器和国产操作系统的逐步推广应用,越来越多的开发人员在国产平台下开发多线程程序.目前国产平台普遍采用的Qt Creator 工具中缺乏可视化的并发性能分析工具,使得优化由于多线程同步/互斥和资源竞争带来的性能问题变得特别困... 随着国产处理器和国产操作系统的逐步推广应用,越来越多的开发人员在国产平台下开发多线程程序.目前国产平台普遍采用的Qt Creator 工具中缺乏可视化的并发性能分析工具,使得优化由于多线程同步/互斥和资源竞争带来的性能问题变得特别困难.设计一种Qt Creator 下的并发性能分析方案,通过实时监控程序并发事件,采集程序运行过程中的并发性能数据,分析程序并发性能瓶颈和死锁原因,并以插件形式进行多视图数据显示.通过实验表明,该并发性能分析方案可以方便、快捷地辅助用户开发多线程并发程序,提高软件开发效率. 展开更多
关键词 国产平台 多线程 并发 QT Creator插件 死锁检测
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Concurrent optimization of structural topology and infill properties with a CBF-based level set method
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作者 Long JIANG Yang GUO +3 位作者 Shikui CHEN Peng WEI Na LEI Xianfeng David GU 《机械工程前沿:英文版》 CSCD 2019年第2期171-189,共19页
In this paper,a parametric level-set-based topology optimization framework is proposed to concurrently optimize the structural topology at the macroscale and the effective infill properties at the micro/meso scale.The... In this paper,a parametric level-set-based topology optimization framework is proposed to concurrently optimize the structural topology at the macroscale and the effective infill properties at the micro/meso scale.The concurrent optimization is achieved by a computational framework combining a new parametric level set approach with mathematical programming.Within the proposed framework,both the structural boundary evolution and the effective infill property optimization can be driven by mathematical programming,which is more advantageous compared with the conventional partial differential equatiodriven level set approach.Moreover,the proposed approach will be more efficient in handling nonlinear problems with multiple constraints.Instead of using radial basis functions(RBF),in this paper,we propose to construct a new type of cardinal basis functions(CBF)for the level set function parameterization.The proposed CBF parameterization ensures an explicit impose of the lower and upper bounds of the design variables.This overcomes the intrinsic disadvantage of the conventional RBF-based parametric level set method,where the lower and upper bounds of the design variables oftentimes have to be set by trial and error;A variational distance regularization method is utilized in this research to regularize the level set function to be a desired distanceregularized shape.With the distance information embedded in the level set model,the wrapping boundary layer and the interior infill region can be naturally defined.The isotropic infill achieved via the mesoscale topology optimization is conformally fit into the wrapping boundary layer using the shape-preserving conformal mapping method,which leads to a hierarchical physical structure with optimized overall topology and effective infill properties.The proposed method is expected to provide a timely solution to the increasing demand for multiscale and multifunctional structure design. 展开更多
关键词 CONCURRENT TOPOLOGY OPTIMIZATION PARAMETRIC level set method cardinal basis function shell-infill structure design confonnal mapping
A Mobile App to Replace the Goniometer? A Pilot Study Focusing on the Measurement of Knee Range of Movement 预览
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作者 Sara Aspinall Tim Sparks +2 位作者 Andrew King Mike Price Steven Godsiff 《运动科学:英文版》 2019年第3期71-80,共10页
Background: The universal goniometer is commonly used to measure knee range of movement in clinical practice. However, research has demonstrated that the universal goniometer lacks reliability failing to meet the stan... Background: The universal goniometer is commonly used to measure knee range of movement in clinical practice. However, research has demonstrated that the universal goniometer lacks reliability failing to meet the standard of clinically acceptable error (5°). Objective: This study tested the concurrent validity and intra-rater reliability of a photographic based “app” developed for feedback in sport, the Hudl Ubersense App, as an alternative instrument for measuring knee range of movement. Methods: Measurements of knee range of movement were made concurrently with the electrogoniometer (the gold standard) and the Hudl Ubersense App across a pre-determined randomised set of 20 functional knee angles between 35° and 130°. This was then repeated. The pre-agreed standard of concurrent validity was that 95% of Hudl Ubersense App measurements would be within 5° of the electrogoniometer and differences were displayed in Bland-Altman plots. Results: Thirty nine (97%) of the forty app readings differed from the corresponding electrogoniometer readings by less than 5°. The mean differences between the electrogoniometer and Hudl Ubersense App measurements over each trial were 1.75° and 0.80° respectively, indicating a high level of concurrent validity. There was less than 1.0° mean difference between the first and second set of results indicating a high level of intra-rater reliability. Conclusions: The results suggest that the Hudl Ubersense App has high levels of concurrent validity (using the electrogoniometer as the gold standard) and intra-rater reliability, scoring better than previous research on the current clinical measuring device, the universal goniometer. The Hudl Ubersense App has clinical advantages over the electrogoniometer, so further research is recommended to determine its inter-rater reliability, acceptability, and appropriate clinical practice procedures. 展开更多
关键词 MOBILE application range of movement KNEE CONCURRENT validity intra-rater reliability.
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影响CT引导下经皮肺穿刺并发气胸的因素分析 预览
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作者 金惠 《中国继续医学教育》 2019年第19期82-84,共3页
目的对影响CT引导下经皮肺穿刺并发气胸的因素进行观察和分析。方法选择2018年6月—2018年12月在医院进行了经皮肺穿刺的60例患者为对象,对其临床治疗的资料进行分析和整理。结果在两组患者之中,并发气胸组患者病灶直径<3cm患者发生... 目的对影响CT引导下经皮肺穿刺并发气胸的因素进行观察和分析。方法选择2018年6月—2018年12月在医院进行了经皮肺穿刺的60例患者为对象,对其临床治疗的资料进行分析和整理。结果在两组患者之中,并发气胸组患者病灶直径<3cm患者发生气胸的概率显著高于≥3cm的患者,病灶距离胸壁距离≥2cm的患者出现气胸的概率显著高于<2cm患者,病灶位置位于肺下叶者出现气胸的概率显著高于病灶位置处于上、中叶的患者,P<0.05,差异有统计学意义。肺气肿、病灶直径<3cm以及病灶位置位于肺下叶均为这一疾病的独立危险因素,P<0.05,差异有统计学意义。结论病灶直径<3cm、病灶距离胸壁距离≥2cm以及病灶位置位于肺下叶的患者极易出现CT引导下经皮肺穿刺并发气胸疾病。 展开更多
关键词 CT引导 经皮肺穿刺 患者 气胸 并发 影响 因素
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脑瘤患者术后并发癫痫的护理研究 预览
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作者 苏冉冉 《科学养生》 2019年第9期69-70,共2页
目的 探讨分析脑瘤患者进行手术之后的癫痫并发症的护理干预情况以及临床价值研究.方法 选取本院2018年7月~2019年6月的40例脑瘤手术后患有并发癫痫的患者作为研究对象,根据入院时间进行分组,分为观察组和对照组各20例,对照组给予常规护... 目的 探讨分析脑瘤患者进行手术之后的癫痫并发症的护理干预情况以及临床价值研究.方法 选取本院2018年7月~2019年6月的40例脑瘤手术后患有并发癫痫的患者作为研究对象,根据入院时间进行分组,分为观察组和对照组各20例,对照组给予常规护理,观察组给予优质护理,观察两组患者护理后癫痫发生率.结果 观察组患者的并发癫痫护理后发生率明显低于对照组(P<0 05).结论 对脑瘤手术患者在术后并发癫痫患者进行优质护理,可以有效降低癫痫发生率,值得推广应用. 展开更多
关键词 脑瘤患者 术后 并发 癫痫 护理
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阑尾炎合并阑尾血吸虫病伴感染的病理特点分析
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作者 周向华 蒋莉 +3 位作者 吴丽琴 杨凡凡 侯春晓 严晓红 《中国地方病防治杂志》 CAS 2019年第2期184-186,共3页
目的探究阑尾炎合并阑尾血吸虫病伴感染的相关临床病理特点。方法本次研究选择2014年2月至2018年7月在本院收治的1 132例急性阑尾炎患者为研究对象,经证实其中共有98例患者为阑尾炎合并阑尾血吸虫病伴有急性感染,为研究组。同时随机在1 ... 目的探究阑尾炎合并阑尾血吸虫病伴感染的相关临床病理特点。方法本次研究选择2014年2月至2018年7月在本院收治的1 132例急性阑尾炎患者为研究对象,经证实其中共有98例患者为阑尾炎合并阑尾血吸虫病伴有急性感染,为研究组。同时随机在1 034例患者中选取98例未合并血吸虫病的急性阑尾炎患者为对照组,详细观察2组患者在临床表现及临床病理学上的特点。结果 1 132例急性阑尾炎患者,确诊阑尾炎合并阑尾血吸虫病伴有急性感染的患者98例,检出率为8.66%。研究组98例阑尾炎合并阑尾血吸虫病伴有急性感染的患者均存在不同程度的右下腹疼痛,合并恶心呕吐的患者73例,占74.49%,发热患者69例,占70.41%,合并右下腹转移性痛的患者68例,占69.39%。对照组98例未合并血吸虫病的急性阑尾炎也存在不同程度的右下腹疼痛,其中合并恶心呕吐的患者71例,占72.45%,发热患者64例,占65.31%,合并右下腹转移性痛的患者61例,占62.24%。2组患者在腹痛、发热及恶性呕吐等症状上比较(P>0.05)。但2组患者在白细胞计数、坏疽及穿孔等相关并发症上比较(P<0.05)。结论阑尾炎合并阑尾血吸虫病伴感染患者术后行病理学常规检查,不仅有利于血吸虫病的监测和控制,同时对于改善患者预后,降低相关并发症及提高医院治疗效果有着重要意义。 展开更多
关键词 阑尾炎 并发 血吸虫病 感染 病理特点
NSCLC根治术后pN2期患者不同放化疗模式的疗效分析
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作者 李秀娟 罗兴波 +3 位作者 张静 谢晓慧 彭晓琴 姚文秀 《肿瘤预防与治疗》 2019年第4期311-318,共8页
目的:比较序贯放化疗(sequential radiochemotherapy,SCRT)与同步放化疗(concurrent chemoradiotherapy,CCRT)在非小细胞肺癌(nonsmallcelllungcancer,NSCLC)根治术后pN2期患者辅助治疗中的价值。方法:选取2012年1月~2017年12月期间,在... 目的:比较序贯放化疗(sequential radiochemotherapy,SCRT)与同步放化疗(concurrent chemoradiotherapy,CCRT)在非小细胞肺癌(nonsmallcelllungcancer,NSCLC)根治术后pN2期患者辅助治疗中的价值。方法:选取2012年1月~2017年12月期间,在四川省肿瘤医院行肺癌根治术后pN2期NSCLC患者92例,据放化疗方式不同分为SCRT组(n=54)和CCRT组(n=38),比较两组副反应,无局部复发生存期(local recurrence free survival,LRFS)、无远处转移生存期(distant metastasis freesurvival,DMFS)、无病生存期(disease free survival,DFS)、总生存(0-verallsurvival,OS)及1年、2年、3年生存率。结果:两组患者在一般资料、病理类型、病理T分期、淋巴结状态等方面差异无统计学意义。CCRT组白细胞减少发生率较SCRT组高,差异有统计学意义(P<0.05),放射性食管炎、放射性肺炎等副反应发生率在两组间差异无统计学意义(P>0.05)。SCRT组的中位DMFS.DFS优于CCRT组,两组的中位LRFS及CCRT组的中位OS暂未达到,但差异均未达到统计学意义(P>0.05),结论:对于根治术后pN2期NSCLC,SCRT与CCRT均是有效的治疗方式,但SCRT的安全性更佳,且SCRT的DMFS、DFS有优于CCRT的趋势,SCRT及CCRT在NSCLC根治术后PN2期患者治疗中的价值有待于进一步探索。 展开更多
关键词 N2 非小细胞肺癌 序贯 同步 放化疗
Android平台下虚拟多串口并发通信的研究 预览
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作者 冉德纲 孙斌 +2 位作者 杨建 申兴发 周红春 《计算机时代》 2019年第5期37-40,共4页
目前Android系统只提供单串口通信,在多串口并发通信方面缺乏基础功能。文章提出虚拟串口方案以解决多串口并发通信问题,将原有唯一串口通过软件接口方式虚拟出多个串口为应用程序提供服务。系统主要由Android源码框架层串口数据流分发... 目前Android系统只提供单串口通信,在多串口并发通信方面缺乏基础功能。文章提出虚拟串口方案以解决多串口并发通信问题,将原有唯一串口通过软件接口方式虚拟出多个串口为应用程序提供服务。系统主要由Android源码框架层串口数据流分发软件和STM32微处理器单串口物理扩展外部电路两部分组成。实验结果表明,在多串口并发通信时,该系统能够提供高效、稳定、可靠的串口数据传输。 展开更多
关键词 ANDROID系统 串口 并发 STM32 事件驱动模型
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Coalition Game Based Full-Duplex Concurrent Scheduling in Millimeter Wave Wireless Backhaul Network 预览
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作者 Haiyan Jiang Yong Niu +2 位作者 Jiayi Zhang Bo Ai Zhangdui Zhong 《中国通信:英文版》 SCIE CSCD 2019年第2期59-75,共17页
With the development of self-interference(SI)cancelation technology,full-duplex(FD)communication becomes possible.FD communication can theoretically double the spectral efficiency.When the time slot(TS)resources are l... With the development of self-interference(SI)cancelation technology,full-duplex(FD)communication becomes possible.FD communication can theoretically double the spectral efficiency.When the time slot(TS)resources are limited and the number of flows is large,the scheduling mechanism of the flows becomes more important.Therefore,the effectiveness of FD scheduling mechanism for the flows is studied in millimeter wave wireless backhaul network with the limited TS resources.We proposed a full duplex concurrent scheduling algorithm based on coalition game(FDCG)to maximize the number of flows with their QoS requirements satisfied.We transformed the problem of maximizing the number of flows with their QoS requirements satisfied into the problem of maximizing sum rate of concurrently scheduled flows in each slot.We obtained the scheduled flows with maximum sum rate in first slot by using coalition game.And then with certain restrictions,the maximum sum rate of concurrently scheduled flows can also be achieved in subsequent time slots.The simulation results show that the proposed FDCG algorithm can achieve superior performance in terms of the number of flows that meet their QoS requirements and system throughput compared with other three algorithms. 展开更多
关键词 MILLIMETER wave wireless BACKHAUL NETWORK coalition game CONCURRENT SCHEDULING maximum SUM rate
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对全喉切除患者及家属同期进行护理的影响 预览
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作者 李艳霞 《中国卫生标准管理》 2019年第6期114-115,共2页
目的分析对全喉切除患者及家属同期实施护理干预的影响。方法针对我院收治的实施全喉切除的喉癌患者50例进行护理观察,随机分成两组后给予常规组25例全喉切除患者实施常规护理,给予观察组25例全喉切除患者及家属实施同期护理干预,对比... 目的分析对全喉切除患者及家属同期实施护理干预的影响。方法针对我院收治的实施全喉切除的喉癌患者50例进行护理观察,随机分成两组后给予常规组25例全喉切除患者实施常规护理,给予观察组25例全喉切除患者及家属实施同期护理干预,对比两组全喉切除患者的护理效果。结果观察组全喉切除患者及家属护理后的生活质量高于常规组全喉切除患者,差异有统计学意义(P<0.05)。结论针对全喉切除患者及家属实施同期护理干预的应用效果显著。 展开更多
关键词 全喉切除 家属 同期 护理干预 护理有效性 生活质量
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急性脑梗死并发肺部感染患者治疗中行康复护理的临床价值研究 预览
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作者 王沛沛 李勤娥 +1 位作者 屈文龙 匡敏玉 《实用心脑肺血管病杂志》 2019年第S1期157-158,共2页
目的分析急性脑梗死并发肺部感染患者治疗中行康复护理的临床价值。方法 2013年8月—2018年6月,于首都医科大学附属北京康复医院收治的急性脑梗死并发肺部感染患者中选取98例,随机分为两组,各49例。对照组行常规护理,观察组在对照组基... 目的分析急性脑梗死并发肺部感染患者治疗中行康复护理的临床价值。方法 2013年8月—2018年6月,于首都医科大学附属北京康复医院收治的急性脑梗死并发肺部感染患者中选取98例,随机分为两组,各49例。对照组行常规护理,观察组在对照组基础上行康复护理,比较两组护理效果、BI(Barthel指数)与NIHSS(美国国立卫生研究院卒中量表)评分情况。结果观察组护理总有效率为95.92%,高于对照组的75.51%,差异有统计学意义(χ2=8.333,P<0.05);观察组护理后NIHSS评分为(4.01±0.52)分,低于对照组的(7.89±1.09)分,BI评分为(75.58±3.59)分,高于对照组的(50.01±1.25)分,组间差异有统计学意义(P<0.05)。结论急性脑梗死并发肺部感染患者治疗中行康复护理的临床价值显著,利于改善患者的神经功能缺损状况,提高日常生活能力,值得推广。 展开更多
关键词 急性脑梗死 肺部感染 并发 康复护理 常规护理 临床价值
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天脉1操作系统上TCP并发服务器设计与实现 预览
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作者 郑涛 赵一煊 张双 《航空计算技术》 2018年第3期114-117,121共5页
航空电子系统信息化和系统复杂性越来越高,航空电子系统上驻留的应用软件越来越多,出现了一个应用软件需要向多个应用软件提供服务的场景,并且应用软件之间的数据交互采用网络技术,以及产品的国产化和自主可控的要求。基于此需求,在天脉... 航空电子系统信息化和系统复杂性越来越高,航空电子系统上驻留的应用软件越来越多,出现了一个应用软件需要向多个应用软件提供服务的场景,并且应用软件之间的数据交互采用网络技术,以及产品的国产化和自主可控的要求。基于此需求,在天脉1操作系统上设计了一个TCP并发服务器软件,着重阐述了天脉1操作系统上TCP并发服务器的模型、TCP并发原理和TCP并发服务器软件架构,并且实现和验证了天脉1操作系统上TCP并发服务器的并发能力,达到了预期的目标。 展开更多
关键词 天脉1操作系统 TCP 并发 服务器
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Concurrent topology optimization for minimization of total mass considering load-carrying capabilities and thermal insulation simultaneously 预览
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作者 Kai Long Xuan Wang Xianguang Gu 《力学学报:英文版》 SCIE EI CAS CSCD 2018年第2期315-326,共12页
The present work introduces a novel concurrent optimization formulation to meet the requirements of lightweight design and various constraints simultaneously.Nodal displacement of macrostructure and effective thermal ... The present work introduces a novel concurrent optimization formulation to meet the requirements of lightweight design and various constraints simultaneously.Nodal displacement of macrostructure and effective thermal conductivity of microstructure are regarded as the constraint functions,which means taking into account both the loadcarrying capabilities and the thermal insulation properties.The effective properties of porous material derived from numerical homogenization are used for macrostructural analysis.Meanwhile,displacement vectors of macrostructures from original and adjoint load cases are used for sensitivity analysis of the microstructure.Design variables in the form of reciprocal functions of relative densities are introduced and used for linearization of the constraint function.The objective function of total mass is approximately expressed by the second order Taylor series expansion.Then,the proposed concurrent optimization problem is solved using a sequential quadratic programming algorithm,by splitting into a series of sub-problems in the form of the quadratic program.Finally,several numerical examples are presented to validate the effectiveness of the proposed optimization method.The various effects including initial designs,prescribed limits of nodal displacement,and effective thermal conductivity on optimized designs are also investigated.An amount of optimized macrostructures and their corresponding microstructures are achieved. 展开更多
关键词 CONCURRENT design TOPOLOGY optimization HOMOGENIZATION Thermal insulation NODAL DISPLACEMENT Independent continuous mapping method
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一种基于测试的消息竞争故障定位方法 预览
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作者 曾奕 《南京师范大学学报:工程技术版》 CAS 2018年第4期44-51,共8页
针对并发程序中由消息竞争所引发的不确定性故障难以捕获与再现、定位结果不精确等问题,提出一种结合程序频域比对、Delta调试策略的故障定位方法.该方法首先建立并发程序执行模型,定义同步序列描述程序执行路径的不确定性,并将其抽象... 针对并发程序中由消息竞争所引发的不确定性故障难以捕获与再现、定位结果不精确等问题,提出一种结合程序频域比对、Delta调试策略的故障定位方法.该方法首先建立并发程序执行模型,定义同步序列描述程序执行路径的不确定性,并将其抽象成简洁的消息竞争序列;而后收集、比对正确的测试执行与错误的测试执行中消息竞争序列间的差异,约简故障搜索空间,获得初始故障集合;最后,为初始故障集合中所对应的每一个失效执行,采用Delta调试策略设计并运行一组附加测试,从而逐步精准地锁定故障根源.初步实验结果表明,该方法能够有效检测消息竞争故障,提高故障定位效率. 展开更多
关键词 并发 不确定性 错误定位 消息竞争
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CRL: Efficient Concurrent Regeneration Codes with Local Reconstruction in Geo-Distributed Storage Systems
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作者 Quan-Qing Xu Wei-Ya Xi +1 位作者 Khai Leong Yong Chao Jin 《计算机科学技术学报:英文版》 SCIE EI CSCD 2018年第6期1140-1151,共12页
As a typical erasure coding choice, Reed-Solomon (RS) codes have such high repair cost that there is a penaltyfor high reliability and storage efficiency, thereby they are not suitable in geo-distributed storage sys... As a typical erasure coding choice, Reed-Solomon (RS) codes have such high repair cost that there is a penaltyfor high reliability and storage efficiency, thereby they are not suitable in geo-distributed storage systems. We present anovel family of concurrent regeneration codes with local reconstruction (CRL) in this paper. The CRL codes enjoy threebenefits. Firstly, they are able to minimize the network bandwidth for node repair. Secondly, they can reduce the numberof accessed nodes by calculating parities from a subset of data chunks and using an implied parity chunk. Thirdly, they arefaster than existing erasure codes for reconstruction in geo-distributed storage systems. In addition, we demonstrate howthe CRL codes overcome the limitations of the Reed-Solomon codes. We also illustrate analytically that they are excellent inthe trade-off between chunk locality and minimum distance. Furthermore, we present theoretical analysis including latencyanalysis and reliability analysis for the CRL codes. By using quantity comparisons, we prove that CRL(6, 2, 2) is only0.657x of Azure LRC(6, 2, 2), where there are six data chunks, two global parities, and two local parities, and CRL(10,4, 2) is only 0.656x of HDFS-Xorbas(10, 4, 2), where there are 10 data chunks, four local parities, and two global paritiesrespectively, in terms of data reconstruction times. Our experimental results show the performance of CRL by conductingperformance evaluations in both two kinds of environments: 1) it is at least 57.25% and 66.85% more than its competitorsin terms of encoding and decoding throughputs in memory, and 2) it has at least 1.46x and 1.21x higher encoding anddecoding throughputs than its competitors in JBOD (Just a Bunch Of Disks). We also illustrate that CRL is 28.79% and30.19% more than LRC on encoding and decoding throughputs in a geo-distributed environment. 展开更多
关键词 CONCURRENT REGENERATION code local RECONSTRUCTION geo-distributed storage system
PBK和基质金属蛋白酶9在宫颈癌中的表达及对同步放化疗疗效的影响 被引量:1
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作者 孙晓革 宝莹娜 +4 位作者 邱惠 石静 张薇 郁志龙 谢丛华 《中华放射医学与防护杂志》 CSCD 北大核心 2018年第7期529-534,共6页
目的 探讨DNA损伤修复因子PBK(PDZ连接激酶)和基质金属蛋白酶9(MMP-9)在宫颈癌中的表达及对同步放化疗疗效的影响。方法 收集2014年1月至2016年7月共65例宫颈鳞癌根治性同步放化疗患者的病理标本,通过免疫组织化学法检测PBK和MMP-... 目的 探讨DNA损伤修复因子PBK(PDZ连接激酶)和基质金属蛋白酶9(MMP-9)在宫颈癌中的表达及对同步放化疗疗效的影响。方法 收集2014年1月至2016年7月共65例宫颈鳞癌根治性同步放化疗患者的病理标本,通过免疫组织化学法检测PBK和MMP-9的表达情况。体外照射采用调强放射治疗,剂量为50 Gy/25次;外照射18次后予以高剂量率后装治疗,30-36 Gy/5-6次,3-4周。外照射开始后给予每周化疗,采用单药顺铂方案,顺铂(DDP)40 mg/m2静脉滴注,连续2-6周。定期随访所有患者,分析患者临床特征、预后与PBK和MMP-9之间的关系。结果 PBK在宫颈癌标本中的阳性表达率为92.3%,MMP-9为69.2%。PBK高表达组的宫颈癌患者总生存率(OS)和疾病无进展生存率(PFS)均明显低于PBK表达低的患者(χ^2=4.324、8.068,P〈0.05),MMP-9高表达组患者的PFS明显低于低表达组(χ^2=5.134,P〈0.05),PBK和MMP-9联合高表达组的OS和PFS比联合低表达组低(χ^2=5.382、9.364,P〈0.05)。结论 PBK和MMP-9在宫颈癌组织中的表达存在差异与宫颈癌的预后相关,联合检测PBK和MMP-9的表达水平可能有助于预测宫颈癌同步放化疗后的疗效。 展开更多
关键词 PBK(PDZ连接激酶) 基质金属蛋白酶9 同步放化疗 宫颈癌
2013~2017年北京某医院无偿献血者构成及血液检测结果分析 预览 被引量:1
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作者 潘雪 关晓珍 +3 位作者 潘纪春 张婷 郭邦胜 汪德清 《临床输血与检验》 CAS 2018年第4期354-357,共4页
目的 分析本院近5年无偿献血者构成及血液标本检测结果,为进一步了解血源阳性检出率、变化特点和制定无偿献血工作策略提供参考依据。方法 选择2013年1月~2017年12月本院无偿献血者(由街头、军队、患者亲友三类无偿献血者构成)共158 ... 目的 分析本院近5年无偿献血者构成及血液标本检测结果,为进一步了解血源阳性检出率、变化特点和制定无偿献血工作策略提供参考依据。方法 选择2013年1月~2017年12月本院无偿献血者(由街头、军队、患者亲友三类无偿献血者构成)共158 027例,采集全血后的血液标本进行初检、复检,主要包括丙氨酸氨基转移酶(ALT)、乙型肝炎病毒(HBV)、丙型肝炎病毒(HCV)、人类免疫缺陷病毒(HIV)及梅毒螺旋体(TP),并对无偿献血者的构成和检测结果进行统计分析。结果 158 027例无偿献血者中街头、军队、患者亲友三类无偿献血者的比例为1∶2.7∶4.4,总不合格率为4.1%,其中街头与军队无偿献血者不合格率低于患者亲友献血者,三类无偿献血者的不合格率比较差异有统计学意义(χ2=22.329,P〈0.05);不同年份总不合格率的差异有统计学意义(χ2=519.222,P〈0.05),以2013年最高;各项不合格检出率由高到低依次为HBsAg〉ALT〉TP〉HCV〉HIV,除HCV外,其他不同年份检测不合格率差异有统计学意义(χ2=2 298.798、41.849、23.547、34.582,P〈0.05);HIV/HBV合并阳性9例,HIV/TP合并阳性29例,HIV/TP/HCV合并阳性1例,其他项目合并阳性共64例,三类无偿献血者合并阳性检出率的差异有统计学意义(χ2=52.707,P〈0.05)。结论 加强血液检测工作及持续关注血源性传染病的阳性检出率变化规律是提高血液质量安全的必要手段。 展开更多
关键词 无偿献血 血液传播疾病 血液检测
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