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机加中的“模随件动”加工法
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作者 贾鹏 《中国新技术新产品》 2013年第6期181-181,共1页
为了回避传统的正交加工刀路带来的各种弊端,不过于追求工艺基准的准确定位,利用数控铣床的进给系统和对刀、找正装置对工艺基准进行测量以确定其实际位置和角度,使用CAM软件在计算机进行相应建模,此时,所建的图模与工件的实际位置和角... 为了回避传统的正交加工刀路带来的各种弊端,不过于追求工艺基准的准确定位,利用数控铣床的进给系统和对刀、找正装置对工艺基准进行测量以确定其实际位置和角度,使用CAM软件在计算机进行相应建模,此时,所建的图模与工件的实际位置和角度完全一致即"模随件动",然后生成刀具轨迹和程序,最终完成加工。 展开更多
关键词 图模 位置 角度" 随件动"
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秦腔戏曲服饰随件中的手帕研究
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作者 赵利利 《中国宽带》 2021年第1期77-77,共1页
秦腔是我国的传统戏曲艺术之一,其戏曲艺术的各个方面都有自身的特色。服饰艺术是戏曲艺术的重要组成部分,秦腔戏曲服饰艺术也具有自身的独特性,不管是戏曲服装,还是服饰随件,都有较强的审美效果和其他方面的功能,对秦腔的整体发展产生... 秦腔是我国的传统戏曲艺术之一,其戏曲艺术的各个方面都有自身的特色。服饰艺术是戏曲艺术的重要组成部分,秦腔戏曲服饰艺术也具有自身的独特性,不管是戏曲服装,还是服饰随件,都有较强的审美效果和其他方面的功能,对秦腔的整体发展产生着重要影响。 展开更多
关键词 秦腔 戏曲服饰 随件 手帕
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机加中的"模随件动"加工法
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作者 段克君 《海外文摘》 2018年第20期91-92,共2页
随着工业化水平的提升,我国的机械制造业在工业生产中的占有比重越来越大,对整个机械加工的生产过程开始进行优化提升,其中针对机械加工的工艺要求,进行详细分析。也是针对“模随件动”加工法对于机械加工效率和质量的提升进行深化分析... 随着工业化水平的提升,我国的机械制造业在工业生产中的占有比重越来越大,对整个机械加工的生产过程开始进行优化提升,其中针对机械加工的工艺要求,进行详细分析。也是针对“模随件动”加工法对于机械加工效率和质量的提升进行深化分析,分析这种加工方法到底是否适合现代机械加工产业使用,在投入使用后到底会产生什么样的效果,“模随件动”加工法对于以往的机械加工形式的弊端是否能针对性地解决,在工艺和技术上“模随件动”加工法采用的到底是那种加工方法,这些都是以下需要讨论的问题点,也是为推广“模随件动”加工法打下基础。 展开更多
关键词 机械加工 “模随件动” 加工法 数控技术 加工方法
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秦腔戏剧服装随件的舞蹈美
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作者 兰宇 《当代戏剧》 北大核心 2015年第2期48-50,共3页
服装随件虽然不是服装的主体,但是它们在装饰戏剧舞台人物的过程中起到了丰富化的作用。在戏剧舞蹈表演中,随件对于人物形象塑造的美化和完善化,对于戏剧舞蹈动作的特殊性发挥等都起到重要的添彩作用,能够辅助人物的唱、念、做、打等动... 服装随件虽然不是服装的主体,但是它们在装饰戏剧舞台人物的过程中起到了丰富化的作用。在戏剧舞蹈表演中,随件对于人物形象塑造的美化和完善化,对于戏剧舞蹈动作的特殊性发挥等都起到重要的添彩作用,能够辅助人物的唱、念、做、打等动作的完美化表现,对于人物外部形象的增色、内心情绪的刻画,对人物风韵、情致的点染,对于戏剧气氛的烘托,对于戏剧情节发展的推动等方面,都是作用巨大,不可忽视。服装随件在戏剧舞蹈表演中具有推波助澜的美学效果。 展开更多
关键词 秦腔 戏剧表演 服装随件 渲染烘托 美学分析
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Semantic role labeling based on conditional random fields 被引量:9
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作者 于江德 樊孝忠 +1 位作者 庞文博 余正涛 《Journal of Southeast University(English Edition)》 EI CAS 2007年第3期361-364,共4页
Due to the fact that semantic role labeling (SRL) is very necessary for deep natural language processing, a method based on conditional random fields (CRFs) is proposed for the SRL task. This method takes shallow ... Due to the fact that semantic role labeling (SRL) is very necessary for deep natural language processing, a method based on conditional random fields (CRFs) is proposed for the SRL task. This method takes shallow syntactic parsing as the foundation, phrases or named entities as the labeled units, and the CRFs model is trained to label the predicates' semantic roles in a sentence. The key of the method is parameter estimation and feature selection for the CRFs model. The L-BFGS algorithm was employed for parameter estimation, and three category features: features based on sentence constituents, features based on predicate, and predicate-constituent features as a set of features for the model were selected. Evaluation on the datasets of CoNLL-2005 SRL shared task shows that the method can obtain better performance than the maximum entropy model, and can achieve 80. 43 % precision and 63. 55 % recall for semantic role labeling. 展开更多
关键词 semantic role labeling conditional random fields parameter estimation feature selection
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TONE MODELING BASED ON HIDDEN CONDITIONAL RANDOM FIELDS AND DISCRIMINATIVE MODEL WEIGHT TRAINING 被引量:1
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作者 黄浩 朱杰 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2008年第1期43-50,共8页
The use of hidden conditional random fields (HCRFs) for tone modeling is explored. The tone recognition performance is improved using HCRFs by taking advantage of intra-syllable dynamic, inter-syllable dynamic and d... The use of hidden conditional random fields (HCRFs) for tone modeling is explored. The tone recognition performance is improved using HCRFs by taking advantage of intra-syllable dynamic, inter-syllable dynamic and duration features. When the tone model is integrated into continuous speech recognition, the discriminative model weight training (DMWT) is proposed. Acoustic and tone scores are scaled by model weights discriminatively trained by the minimum phone error (MPE) criterion. Two schemes of weight training are evaluated and a smoothing technique is used to make training robust to overtraining problem. Experiments show that the accuracies of tone recognition and large vocabulary continuous speech recognition (LVCSR) can be improved by the HCRFs based tone model. Compared with the global weight scheme, continuous speech recognition can be improved by the discriminative trained weight combinations. 展开更多
关键词 speech recognition MODELS hidden conditional random fields minimum phone error
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Design and analysis of traffic incident detection based on random forest 被引量:8
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作者 刘擎超 陆建 陈淑燕 《Journal of Southeast University(English Edition)》 EI CAS 2014年第1期88-95,共8页
In order to avoid the noise and over fitting and further improve the limited classification performance of the real decision tree, a traffic incident detection method based on the random forest algorithm is presented.... In order to avoid the noise and over fitting and further improve the limited classification performance of the real decision tree, a traffic incident detection method based on the random forest algorithm is presented. From the perspective of classification strength and correlation, three experiments are performed to investigate the potential application of random forest to traffic incident detection: comparison with a different number of decision trees; comparison with different decision trees; comparison with the neural network. The real traffic data of the 1-880 database is used in the experiments. The detection performance is evaluated by the common criteria including the detection rate, the false alarm rate, the mean time to detection, the classification rate and the area under the curve of the receiver operating characteristic (ROC). The experimental results indicate that the model based on random forest can improve the decision rate, reduce the testing time, and obtain a higher classification rate. Meanwhile, it is competitive compared with multi-layer feed forward neural networks (MLF). 展开更多
关键词 intelligent transportation system random forest traffic incident detection traffic model
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Polar Functions for Fractional Brownian Motion
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作者 肖益民 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第1期76-80,共5页
Let X (t)(t∈R^N) be a d-dimensional fractional Brownian motion. A contiunous function f:R^N→R^d is called a polar function of X(t)(t∈R^N) if P{ t∈R^N\{0},X(t)=t(t)}=0. In this paper, the characteristies of the cla... Let X (t)(t∈R^N) be a d-dimensional fractional Brownian motion. A contiunous function f:R^N→R^d is called a polar function of X(t)(t∈R^N) if P{ t∈R^N\{0},X(t)=t(t)}=0. In this paper, the characteristies of the class of polar functions are studied. Our theorem 1 improves the previous results of Graversen and Legall. Theorem2 solves a problem of Legall (1987) on Brownian motion. 展开更多
关键词 fractional Brownian motion polar function Lipschitz function class quasi-helix Hausdorff dimension
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Analysis of 3D curve expansion of conical cam with oscillating tapered roller follower 被引量:5
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作者 CHEN Jun-hua WU Yi-jie 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第11期1789-1794,共6页
This paper focuses on the analysis of running conditions and machining processes of conical cam with oscillating follower. We point out the common errors existing in the design and machining of the widely used plane e... This paper focuses on the analysis of running conditions and machining processes of conical cam with oscillating follower. We point out the common errors existing in the design and machining of the widely used plane expansion method of conical cam trough-out line. We show that the motion can be divided into two parts, i.e. the oscillating motion of oscillating bar and the rotary motion of oscillating bar relative to the conical cam. By increasing the rotary motion of oscillating bar, the motion path of tapered roller on oscillating bar (i.e. contour surface of conical cam) can be expanded on the cylinder. Based on these analyses, we present a creative and effective designing and machining method for 3D curve expansion of conical cam with oscillating follower. 展开更多
关键词 Oscillating follower Conical cam Tapered roller plane expansion 3D curve expansion
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Optimizing the wavefield storage strategy in reflection-acoustic logging reverse-time migration 被引量:5
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作者 Li Yu-Sheng Li Ning +3 位作者 Yuan ye Wu Hong-Liang Feng Zhou Liu Peng 《Applied Geophysics》 SCIE CSCD 2019年第4期530-538,562,共10页
In this paper,wavefield storage optimization strategies are discussed with respect to reverse-time migration(RTM)imaging in reflection-acoustic logging,considering the problem of massive wavefield data storage in RTM ... In this paper,wavefield storage optimization strategies are discussed with respect to reverse-time migration(RTM)imaging in reflection-acoustic logging,considering the problem of massive wavefield data storage in RTM itself.In doing so,two optimization methods are proposed and implemented to avoid wavefield storage.Firstly,the RTM based on the excitation-amplitude imaging condition uses the excitation time to judge the imaging time,and accordingly,we only need to store a small part of wavefield,such as the wavefield data of dozens of time points,the instances prove that they can even be imaged by only two time points.The traditional RTM usually needs to store the wavefield data of thousands of time points,compared with which the data storage can be reduced by tens or even thousands of times.Secondly,the RTM based on the random boundary uses the idea that the wavefield scatters rather than reflects in a random medium to reconstruct the wavefield source and thereby directly avoid storing the forward wavefield data.Numerical examples show that compared with other migration algorithms and the traditional RTM,both methods can effectively reduce wavefield data storage as well as improve data-processing efficiency while ensuring imaging accuracy,thereby providing the means for high-efficiency and highprecision imaging of fractures and caves by boreholes. 展开更多
关键词 reflection-acoustic logging RTM excitation-amplitude imaging condition random boundary
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Deprescribing antihypertensive treatment in nursing home patients and the effect on blood pressure 被引量:2
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作者 Christine Gulla Elisabeth Flo +1 位作者 Reidun LS Kjome Bettina S Husebo 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2018年第4期275-283,共9页
Background It is debatable whether treating multimorbid nursing home patients with antihypertensive drugs produces beneficial effects. Most cardiovascular guidelines promote treatment; few have advice on how to depres... Background It is debatable whether treating multimorbid nursing home patients with antihypertensive drugs produces beneficial effects. Most cardiovascular guidelines promote treatment; few have advice on how to deprescribe when treatment may no longer be necessary. We investigated the effect of medication review on antihypertensive drug use and the association between cognition, blood pressure, and prescribing. Methods From August 2014 to December 2015, 765 patients from 72 units (clusters) in 32 Norwegian nursing homes were included in a 4-month, multicentre, cluster-randomized, controlled trial, with 9-month follow-up. Patients ≥ 65 years old with antihypertensive treatment (n = 295, 39%) were randomized to systematic medication review where the physician received support from peers (collegial mentoring) or were given care as usual (control condition). Outcome measures were the number of antihypertensive drugs, systolic blood pressure, and pulse. We used hospitalizations and deaths as criteria to assess harm. Results At baseline, each patient used 9.2 ± 3.5 regular drugs, and 1.6 ± 0.7 antihypertensives. Mean blood pressure was 128/71 mmHg and 9% had a systolic pressure ≥ 160 mmHg. Between baseline and month four, antihypertensives were deprescribed to a significantly higher extent in the intervention group (n = 43, 32%) compared to control (n = 11, 10%); Incidence Rate Ratio = 0.8, 95% CI = 0.7?0.9. In the intervention group, there was an immediate increase in systolic blood pressure when antihypertensives were reduced, from baseline 128 ± 19.5 mmHg to 143 ± 25.5 mmHg at month four. However, at month nine, the blood pressure had reverted to baseline values (mean 134 mmHg). Deprescription did not affect pulse and systolic pressure. The number of hospitalizations was higher in control patients at month four (P = 0.031) and nine (P = 0.041). Conclusion A systematic medication review supported by collegial mentoring significantly decreased the use of antihypertensive drugs in nursing home patients without an effect on the systolic blood pressure over time. 展开更多
关键词 Antihypertensive drugs Deprescribing HYPERTENSION Long-term care Medication review
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Subtle trap recognition based on seismic sedimentology- A case study from Shengli Oilfield 被引量:10
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作者 Huang Handong Zhang Ruwei +2 位作者 Luo Qun Zhao Di Peng Yongmin 《Applied Geophysics》 SCIE CSCD 2009年第2期175-183,共9页
Seismic sedimentology is the study of sedimentary rocks and facies using seismic data. However, often the sedimentary body features can't be described quantitatively due to the limit of seismic resolution. High resol... Seismic sedimentology is the study of sedimentary rocks and facies using seismic data. However, often the sedimentary body features can't be described quantitatively due to the limit of seismic resolution. High resolution inversion offsets this limitation and is applied to seismic sedimentology to identify subtle traps under complex geologic conditions, thereby widening the applicable range of seismic sedimentology. In this paper, based on seismic sedimentology, seismic phase-controlled nonlinear random inversion is used to predict the sandy conglomerate reservoir of Es3 in the Chezhen depression in Shengli Oilfield. Thickness and sedimentary microfacies maps of sandy conglomerate bodies in several stages are presented and several subtle traps were predicted and verified by drilling. 展开更多
关键词 Seismic sedimentology subtle trap phase-controlled inversion seismic data Jiyang depression
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Adaptive foreground and shadow segmentation using hidden conditional random fields 被引量:1
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作者 CHU Yi-ping YE Xiu-zi +2 位作者 QIAN Jiang ZHANG Yin ZHANG San-yuan 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第4期586-592,共7页
Video object segmentation is important for video surveillance, object tracking, video object recognition and video editing. An adaptive video segmentation algorithm based on hidden conditional random fields (HCRFs) is... Video object segmentation is important for video surveillance, object tracking, video object recognition and video editing. An adaptive video segmentation algorithm based on hidden conditional random fields (HCRFs) is proposed, which models spatio-temporal constraints of video sequence. In order to improve the segmentation quality, the weights of spatio-temporal con- straints are adaptively updated by on-line learning for HCRFs. Shadows are the factors affecting segmentation quality. To separate foreground objects from the shadows they cast, linear transform for Gaussian distribution of the background is adopted to model the shadow. The experimental results demonstrated that the error ratio of our algorithm is reduced by 23% and 19% respectively, compared with the Gaussian mixture model (GMM) and spatio-temporal Markov random fields (MRFs). 展开更多
关键词 Video segmentation Shadow elimination Hidden conditional random fields (HCRFs) On-line learning
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Approach to minish scattering of results for split Hopkinson pressure bar test 被引量:1
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作者 李夕兵 周子龙 赵阳升 《Journal of Central South University of Technology》 EI 2007年第3期404-407,共4页
Split Hopkinson pressure bar(SHPB) apparatus, usually used for testing behavior of material in median and high strain-rate, is now widely used in the study of rock dynamic constitutive relation, damage evolvement me... Split Hopkinson pressure bar(SHPB) apparatus, usually used for testing behavior of material in median and high strain-rate, is now widely used in the study of rock dynamic constitutive relation, damage evolvement mechanism and energy consumption. However, the possible reasons of sampling disturbance, machining error and so on often lead to the scattering of test results, and bring ultimate difficulty for forming general test conclusion. Based on the stochastic finite element method, the uncertain parameters of specimen density ps, specimen radius Rs, specimen elastic modulus Es and specimen length Ls in the data processing of SHPB test were considered, and the correlation between the parameters and the test results was analyzed. The results show that the specimen radius Rs has direct correlation with the test result, improving the accuracy in preparing and measuring of specimen is an effective way to improve the accuracy of test and minish the scattering of results for SHPB test. 展开更多
关键词 split Hopkinson pressure bar test data scattering stochastic finite element method(SFEM)
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Studies of reasonability of computing return period of storm surge based on random events set
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作者 LI Xuan GONG Mao-xun +1 位作者 KANG Xing CHEN Bing-rui 《Marine Science Bulletin》 CAS 2017年第1期24-36,共13页
In order to study whether the random events set can be used in Rudongbank of Nantong or not, we use ADCIRC model to stimulate the storm surge affectingRudong bank based on random events set. Then we use p-III curve to... In order to study whether the random events set can be used in Rudongbank of Nantong or not, we use ADCIRC model to stimulate the storm surge affectingRudong bank based on random events set. Then we use p-III curve to fit peak-value ofsurge of all the years to get the surge of typical return periods. The result shows that theresults of fitting by ADCIRC and by historical data coincide well in lower return periods,but to higher return periods, the results of fitting by ADCIRC are significantly higher thanthat of fitting by historical data. Due to the short time, it’s not enough for the extremestorm surge events to occur, the results of higher return periods are not reliable, so wecan’t rule out the reasonability of results based on random events set. The results offitting based on random events set are accurate in lower return periods and we can alsofully estimate the surge of higher return periods based on random events set. In thesituation of lacking historical data of hundreds of years, random events set can beaccepted as a tool to compute the return period of storm surge. Consideration of globalwarming, the possibility of super typhoons’ appearance will rise, which will result inhigher surge of return periods. In order to prevent the disaster of storm surge, thegovernment needs to deepen and reinforce the coastal engineering like seawalls and embankments. 展开更多
关键词 random events set storm surge reasonability
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Science Letters:Crossover randomized controlled trial of the electronic version of the Chinese SF-36 被引量:2
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作者 CHEN Tian-hui LI Lu +3 位作者 SIGLE Joerg M. DU Ya-ping WANG Hong-mei LEI Jun 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2007年第8期604-608,共5页
Objectives:to verify the feasibility and reliability of the electronic version of Chinese SF-36 based on the Quality-of-Life-Recorder. Design: A crossover randomized controlled trial, comparing a paper-based and an el... Objectives:to verify the feasibility and reliability of the electronic version of Chinese SF-36 based on the Quality-of-Life-Recorder. Design: A crossover randomized controlled trial, comparing a paper-based and an electronic version of the Chinese SF-36, was conducted. According to generated random numbers, interviewees were asked to fill out either the electronic version or the paper version first. The second version was filled in after a pause of at least 10 min. Settings and participants: One group of 100 medical students at the School of Medicine of Zhejiang University and the other group of 50 outpatients at a clinic for general practice in Hangzhou City (China) were eventually recruited in this study. Results: The acceptance of the electronic version was good (60% of medical students and 84% of outpatients preferred the electronic version). At the level of eight-scale scores, the mean-difference for each scale (except for general health) between the two versions was less than 5%. At the level of 36 questions, the percentage of "exact agreement" ranged within 64%~99%; the percentage of "global agreement" ranged within 72%~99%; 77% of the kappa coefficients demonstrated "good/excellent agreement" and 23% of the kappa coefficients demonstrated "medium agreement". Conclusion: This study, for the first time, can provide empirical basis for the confirmation of the feasibility and reliability of the electronic version of the Chinese SF-36 and may provide an impulse towards widespread deployment of the Quality-of-Life-Recorder in Chinese populations. 展开更多
关键词 Health-related quality of life (HRQoL) SF-36 Electronic questionnaire Computer based testing General practice Randomized control trial Feasibility Reliability
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Health-related quality of life of 256 recipients after liver transplantation 被引量:6
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作者 Pei-Xian Chen Lu-Nan Yan Wen-Tao Wang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第36期5114-5121,共8页
AIM:To investigate health-related quality of life(HRQoL) and psychological outcomes in 256 adults who had undergone liver transplantation(LT).METHODS:A stratified random sampling method was used in this follow-up mult... AIM:To investigate health-related quality of life(HRQoL) and psychological outcomes in 256 adults who had undergone liver transplantation(LT).METHODS:A stratified random sampling method was used in this follow-up multicenter study to select a representative sample of recipients undergoing either living donor liver transplantation(LDLT) or deceased donor liver transplantation(DDLT).HRQoL was measured by using the Chinese version of Medical Outcome Study Short Form-36(SF-36),and psychological outcomes by using the beck anxiety inventory(BAI) and the self-rating depression scale(SDS).Clinical and demographic data were collected from the records of the Chinese Liver Transplant Registry and via questionnaires.RESULTS:A total of 256 patients were sampled,including 66(25.8%) receiving LDLT and 190(74.2%) undergoing DDLT;15(5.9%) recipients had anxiety and four(1.6%) developed severe depression after the operation.Compared with LDLT recipients,DDLT patients had higher scores in general health(60.33 ± 16.97 vs 66.86 ± 18.42,P = 0.012),role-physical(63.64 ± 42.55 vs 74.47 ± 36.46,P = 0.048),roleemotional(61.11 ± 44.37 vs 78.95 ± 34.31,P = 0.001),social functioning(78.60 ± 22.76 vs 88.16 ± 21.85,P = 0.003),vitality(70.30 ± 15.76 vs 75.95 ± 16.40,P = 0.016),mental health(65.88 ± 12.94 vs 71.85 ± 15.45,P = 0.005),physical component summary scale(PCS,60.07 ± 7.36 vs 62.58 ± 6.88,P = 0.013) and mental component summary scale(MCS,52.65 ± 7.66 vs 55.95 ± 10.14,P = 0.016).Recipients > 45 years old at the time of transplant scored higher in vitality(77.33 ± 15.64 vs 72.52 ± 16.66,P = 0.020),mental health(73.64 ± 15.06 vs 68.00 ± 14.65,P = 0.003) and MCS(56.61 ± 10.00 vs 54.05 ± 9.30,P = 0.037) than those aged ≤ 45 years.MCS was poorer in recipients with than in those without complications(52.92 ± 12.21 vs 56.06 ± 8.16,P = 0.017).Regarding MCS(55.10 ± 9.66 vs 50.0 ± 10.0,P < 0.05) and PCS(61.93 ± 7.08 vs 50.0 ± 10.0,P < 0.05),recipients scored better than the Sichuan general and had improved overall QoL compared to patients with chronic diseases.MCS and PCS significantly correlated with scores of the BAI(P < 0.001) and the SDS(P < 0.001).CONCLUSION:Age > 45 years at time of transplant,DDLT,full-time working,no complications,anxiety and depression were possible factors influencing postoperative HRQoL in liver recipients. 展开更多
关键词 Liver transplantation Living donor livertransplantation Deceased donor liver transplantation PSYCHOLOGY Health-related quality of life
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A content aware chunking scheme for data de-duplication in archival storage systems
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作者 Nie Xuejun Qin Leihua Zhou Jingli 《High Technology Letters》 EI CAS 2012年第1期45-50,共6页
Based on variable sized chunking, this paper proposes a content aware chunking scheme, called CAC, that does not assume fully random file contents, but tonsiders the characteristics of the file types. CAC uses a candi... Based on variable sized chunking, this paper proposes a content aware chunking scheme, called CAC, that does not assume fully random file contents, but tonsiders the characteristics of the file types. CAC uses a candidate anchor histogram and the file-type specific knowledge to refine how anchors are determined when performing de- duplication of file data and enforces the selected average chunk size. CAC yields more chunks being found which in turn produces smaller average chtmks and a better reduction in data. We present a detailed evaluation of CAC and the experimental results show that this scheme can improve the compression ratio chunking for file types whose bytes are not randomly distributed (from 11.3% to 16.7% according to different datasets), and improve the write throughput on average by 9.7%. 展开更多
关键词 data de-duplicate content aware chunking (CAC) candidate anchor histogram (CAH)
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Early Stage Software Reliability Estimation with Stochastic Reward Nets
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作者 赵靖 刘宏伟 +1 位作者 崔刚 杨孝宗 《Journal of Donghua University(English Edition)》 EI CAS 2005年第3期33-36,共4页
This paper presents software reliability modeling issues at the early stage of a software development for fault tolerant software management system. Based on Stochastic Reward Nets, an effective model of hierarchical ... This paper presents software reliability modeling issues at the early stage of a software development for fault tolerant software management system. Based on Stochastic Reward Nets, an effective model of hierarchical view for a fault tolerant software management system is put forward, and an approach that consists of system transient performance analysis is adopted. A quantitative approach for software reliability analysis is given. The results show its usefulness for the design and evaluation of the early-stage software reliability modeling when failure data is not available. 展开更多
关键词 software reliability software reliability evaluation early-stage software reliability growth model stochastic reward nets Hierarchical model
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Survivability analysis of wireless Ad hoc network using stochastic reward nets
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作者 赵靖 崔刚 +1 位作者 刘宏伟 王慧强 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2008年第4期535-539,共5页
To provide services in presence of failures or attacks in a timely manner, the network survivability was analyzed. Based on stochastic Petri nets, we put forward an effective model for ad hoe network and adopt a two-p... To provide services in presence of failures or attacks in a timely manner, the network survivability was analyzed. Based on stochastic Petri nets, we put forward an effective model for ad hoe network and adopt a two-phase approach consisting of the steady-state availability analysis and the system transient performance analysis, then provide a quantitative approach for analysis of the network survivability. The results show that the proposed model is useful for the design and evaluation of the wireless ad hoc network. 展开更多
关键词 SURVIVABILITY availability ad hoc network stochastic Petri nets
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