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QGP中夸克静色电场的起伏研究
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作者 白鸽 《华中师范大学学报(自然科学版)》 CAS CSCD 北大核心 1997年第1期28-32,共5页
利用QGP中存在德拜屏蔽现象以及高温极限下QGP中夸克的分布函数和色电势,得到QGP中夸克静色电场的起伏。
关键词 等离子体 夸克 屏蔽位势 静色电场 QGP
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QGP中夸克静色电波的辐射研究
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作者 白鸽 李家荣 《高能物理与核物理》 EI CSCD 北大核心 1997年第11期1011-1017,共7页
利用QGP中存在德拜屏蔽现象以及高温极限下QGP中夸克的分布函数和色电势,得到QGP中夸克静色电波的辐射功率。讨论了夸克静色电波的辐射功率与德拜长度的关系,有助于利用辐射功率研究德拜屏蔽位势。
关键词 夸克胶子 等离子体 QGP动力论方程 静色电波
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The Effect of Hydrostatic Pressure Fields on the Dispersion Characteristics of Fluid-shell Coupled System 被引量:5
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作者 刘志忠 李天匀 +1 位作者 朱翔 张俊杰 《Journal of Marine Science and Application》 2010年第2期129-136,共8页
The effect of hydrostatic pressure on the vibration dispersion characteristics of fluid-shell coupled structures was studied.Both fluid-loaded cylindrical shells and fluid-filled cylindrical shells were considered.Num... The effect of hydrostatic pressure on the vibration dispersion characteristics of fluid-shell coupled structures was studied.Both fluid-loaded cylindrical shells and fluid-filled cylindrical shells were considered.Numerical analysis was applied to solve the dispersion equations for shells filled with or loaded with fluid at various hydrostatic pressures.The results for external pressure showed that non-dimensional axial wave numbers are nearly independent when the pressure is below the critical level.The influence of internal pressure on wave numbers was found significant for the real branch s=1 and the complex branches of dispersion curves.The presence of internal pressure increased the cut on frequencies for the branch s=1 for high order wave modes. 展开更多
关键词 hydrostatic pressure DISPERSION fluid-shell coupled system wave propagation
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Vehicle Detection in Still Images by Using Boosted Local Feature Detector 被引量:1
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作者 Young-joon HAN Hern-soo HAHN 《Journal of Measurement Science and Instrumentation》 CAS 2010年第1期41-45,共5页
Vehicle detectition in still images is a comparatively difficult task. This paper presents a method for this task by using boosted local pattern detector constructed from two local features including Haar-like and ori... Vehicle detectition in still images is a comparatively difficult task. This paper presents a method for this task by using boosted local pattern detector constructed from two local features including Haar-like and oriented gradient features. The whole process is composed of three stages. In the first stage, local appearance features of vehicles and non-vehicle objects are extracted. Haar-tike and oriented gradient features are extracted separately in this stage as local features. In the second stage, Adabeost algorithm is used to select the most discriminative features as weak detectors from the two local feature sets, and a strong local pattern detector is built by the weighted combination of these selected weak detectors. Finally, vehicle detection can be performed in still images by using the boosted strong local feature detector. Experiment results show that the local pattern detector constructed in this way combines the advantages of Haar-like and oriented gradient features, and can achieve better detection results than the detector by using single Haar-like features. 展开更多
关键词 vehicle detection still image ADABOOST local features
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Maintenance time of sedative effects after an intravenous infusion of diazepam: A guide for endoscopy using diazepam
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作者 Mitsushige Sugimoto Takahisa Furuta +8 位作者 Akiko Nakamura Naohito Shirai Mutsuhiro Ikuma Shingen Misaka Shinya Uchida Hiroshi Watanabe Kyoichi Ohashi Takashi Ishizaki Akira Hishida 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第33期5197-5203,共7页
AIM: To examine whether the sedative effects assessed by psychomotor tests would depend on the cytochrome P450 (CYP ) 2C19 genotypes after an infusion regimen of diazepam commonly used forgastrointestinal endoscopy in... AIM: To examine whether the sedative effects assessed by psychomotor tests would depend on the cytochrome P450 (CYP ) 2C19 genotypes after an infusion regimen of diazepam commonly used forgastrointestinal endoscopy in Japan. METHODS: Fifteen healthy Japanese volunteers consisting of three different CYP2C19 genotype groups underwent a critical ? icker fusion test, an eye movement analysis and a postural sway test as a test for physical sedative effects, and a visual analog scale (VAS) symptom assessment method as a test for mental sedative effects during the 336 h period after the intravenous infusion of diazepam (5 mg). RESULTS: The physical sedative effects assessed by the critical flicker test continued for 1 h (t values of 5 min, 30 min and 60 min later: 4.35, 5.00 and 3.19, respectively) and those by the moving radial area of a postural sway test continued for 3 h (t values of 5 h, 30 h, 60 min and 3 h later: -4.05, -3.42, -2.17 and -2.58, respectively), which changed significantly compared with the baseline level before infusion (P < 0.05). On the other hand, the mental sedative effects by the VAS method improved within 1 h. The CYP2C19 genotype-dependent differences in the postinfusion sedative effects were not observed in any of the four psychomotor function tests. CONCLUSION: With the psychomotor tests, the objective sedative effects of diazepam continued for 1 h to 3 h irrespective of CYP2C19 genotype status and the subjective sedative symptoms improved within 1 h. Up to 3 h of clinical care appears to be required after the infusion of diazepam, although patients feel subjectively improved. 展开更多
关键词 DIAZEPAM SEDATION cytochrome P450(CYP) 2C19 ENDOSCOPY Complication Critical flicker fusion test Eye movement analysis Postural sway test Visual analog scale
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Structural damage identification using test static data based on grey system theory 被引量:4
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作者 陈孝珍 朱宏平 陈传尧 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第8期790-796,共7页
A new structural damage identification method using limited test static displacement based on grey system theory is proposed in this paper. The grey relation coefficient of displacement curvature is defined and used t... A new structural damage identification method using limited test static displacement based on grey system theory is proposed in this paper. The grey relation coefficient of displacement curvature is defined and used to locate damage in the structure, and an iterative estimation scheme for solving nonlinear optimization programming problems based on the quadratic programming technique is used to identify the damage magnitude. A numerical example of a cantilever beam with single or multiple damages is used to examine the capability of the proposed grey-theory-based method to localize and identify damages. The factors of meas-urement noise and incomplete test data are also discussed. The numerical results showed that the damage in the structure can be localized correctly through using the grey-related coefficient of displacement curvature, and the damage magnitude can be iden-tified with a high degree of accuracy, regardless of the number of measured displacement nodes. This proposed method only requires limited static test data, which is easily available in practice, and has wide applications in structural damage detection. 展开更多
关键词 Damage identification Grey relation coefficient Static test data
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EVALUATION OF THE DIAGNOSTIC CRITERIA FOR THE LOCALIZATION OF ACQUIRED ARTERIOVENOUS FISTULAS BY COLOR DOPPLER FLOW IMAGING
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作者 李建初 蔡胜 +2 位作者 姜玉新 张缙熙 王岩青 《Chinese Medical Sciences Journal》 CAS CSCD 2001年第4期236-240,共5页
Objective. To evaluate the diagnostic criteria for the localization of acquired arteriovenous fistulas (AVFs) by color Doppler flow imaging (CDFI) based on the features of their hemodynamic changes. Methods. The shape... Objective. To evaluate the diagnostic criteria for the localization of acquired arteriovenous fistulas (AVFs) by color Doppler flow imaging (CDFI) based on the features of their hemodynamic changes. Methods. The shape and hemodynamic changes of involved vessels which could be helpful to localize the sites of fistulas were studied according to the observation of 10 cases of acquired AVFs. Results. The sites of the fistulas could be shown by two dimensional ultrasonography and color flow imaging in 40%and 80%cases, respectively. In all cases, turbulent high velocity flow was present at the sites of the fistulas, low resistant flow was present in the arteries proximal to the fistulas, and artery like flow was detected in the veins. Conclusion. CDFI was accurate for the localization of acquired AVFs, which were mainly localized by their hemodynamic changes shown by pulse Doppler ultrasound. 展开更多
关键词 arteriovenous fistula ULTRASONOGRAPHY DOPPLER
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Percutaneous portal venoplasty and stenting for anastomotic stenosis after liver transplantation 被引量:7
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作者 Bao-Jie Wei Ren-You Zhai Jian-Feng Wang Ding-Ke Dai Ping Yu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第15期1880-1885,共6页
AIM:To review percutaneous transhepatic portal venoplasty and stenting(PTPVS)for portal vein anastomotic stenosis(PVAS)after liver transplantation (LT). METHODS:From April 2004 to June 2008,16 of 18 consecutive patien... AIM:To review percutaneous transhepatic portal venoplasty and stenting(PTPVS)for portal vein anastomotic stenosis(PVAS)after liver transplantation (LT). METHODS:From April 2004 to June 2008,16 of 18 consecutive patients(11 male and 5 female;aged 17-66 years,mean age 40.4 years)underwent PTPVS for PVAS.PVAS occurred 2-10 mo after LT(mean 5.0 mo). Three asymptomatic patients were detected on routine screening color Doppler ultrasonography(CDUS). Fifteen patients who also had typical clinical signs of portal hypertension(PHT)were identified by contrastenhanced computerized tomography(CT)or magnetic resonance imaging.All procedures were performed under local anesthesia.If there was a PVAS<75%, the portal pressure was measured.Portal venoplasty was performed with an undersized balloon and slowly inflated.All stents were deployed immediately following the predilation.Follow-ups,including clinical course, stenosis recurrence and stent patency which were evaluated by CDUS and CT,were performed. RESULTS:Technical success was achieved in all patients.No procedure-related complications occurred. Liver function was normalized gradually and the symptoms of PHT also improved following PTPVS.In 2 of 3 asymptomatic patients,portal venoplasty and stenting were not performed because of pressure gradients<5 mmHg.They were observed with periodic CDUS or CT.PTPVS was performed in 16 patients.In 2 patients,the mean pressure gradients decreased from 15.5 mmHg to 3.0 mmHg.In the remaining 14 patients,a pressure gradient was not obtained because of>75%stenosis and typical clinical signs of PHT.In a 51-year-old woman,who suffered from massive ascites and severe bilateral lower limb edema after secondary LT,PVAS complicated hepatic vein stenosis and inferior vena cava(IVC)stenosis. Before PTPVS,a self-expandable and a balloonexpandable metallic stent were deployed in the IVC and right hepatic vein respectively.The ascites and edema resolved gradually after treatment.The portosystemic collateral vessels resulting from PHT were visualized in 14 patients.Gastroesophageal varices became invisible on poststenting portography in 9 patients.In a 28-yearold man with hepatic encephalopathy,a pre-existing meso-caval shunt was detected due to visualization of IVC on portography.After stenting,contrast agents flowed mainly into IVC via the shunt and little flowed into the portal vein.A covered stent was deployed into the superior mesenteric vein to occlude the shunt. Portal hepatopetal flow was restored and the IVC became invisible.The patient recovered from hepatic encephalopathy.A balloon-expandable Palmaz stent was deployed into hepatic artery for anastomotic stenosis before PTPVS.Percutaneous transhepatic internal-external biliary drainage was performed in 2 patients with obstructive jaundice.Portal venous patency was maintained for 3.3-56.6 mo(mean 33.0 mo) and all patients remained asymptomatic.CONCLUSION:With technical refinements,early detection and prompt treatment of complications,and advances in immunotherapy,excellent results can be achieved in LT. 展开更多
关键词 Portal vein Anastomotic stenosis Venoplasty STENT Liver transplantation
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Dirac Quasinormal Modes of Reissner-Ndstrom Black Hole Surrounded by Quintessence
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作者 王春艳 张钰 +1 位作者 桂元星 吕建波 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第5期882-888,共7页
Using the third-order WKB approximation, we evaluate the quasinormal frequencies of massless Dirac field perturbation around a Reissner Nordstrom black hole surrounded by a static and spherically symmetric quintessenc... Using the third-order WKB approximation, we evaluate the quasinormal frequencies of massless Dirac field perturbation around a Reissner Nordstrom black hole surrounded by a static and spherically symmetric quintessence. We study the variation of quasinormal frequencies with the quintessential state parameter ε, the total angular momentum number |k|, the charge Q, and the overtone number n changes, respectively. Moreover, from the results we obtained, we find that the massless Dirac field damps more slowly due to the presence of quintessence. 展开更多
关键词 Dirac field quasinormal frequencies WKB approximation QUINTESSENCE
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The first report of treatment of liver abscess due to Candida albicans with intra-abscess and intravenous administration of liposomal amphotericin B (Amphotec)
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作者 廖万清 姚志荣 +4 位作者 温海 徐红 杨松林 刘兴华 谭卫萍 《Journal of Medical Colleges of PLA(China)》 CAS 2005年第3期191-192,共2页
Increasing reports on application and safety of liposomal amphotericin B (Amphotec) in the treatment of deep fungal infections have been described recently. This is the first report that a case of liver abscess due to... Increasing reports on application and safety of liposomal amphotericin B (Amphotec) in the treatment of deep fungal infections have been described recently. This is the first report that a case of liver abscess due to Candida albicans was completely cured with intra-abscess and intravenous administration of liposomal amphotericin B without recurrence in three-year follow-up period. 展开更多
关键词 liposomal amphotericin B Candida albicans liver abscess
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Electrostatic Waves in Weakly Magnetized Quantum Plasmas
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作者 王春华 孙晓霞 王超群 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第4期771-772,共2页
By using the quantum magnetohydrodynamic model, the electrostatic waves in weakly magnetized quantum plasmas are investigated. The electrons are treated as a quantum and magnetized species, while the ions are classica... By using the quantum magnetohydrodynamic model, the electrostatic waves in weakly magnetized quantum plasmas are investigated. The electrons are treated as a quantum and magnetized species, while the ions are classical unmagnetized ones. The general dispersion relations are derived. It is shown that, both the high frequency electron waves (Langmuire wave and upper-hybrid wave) and the low frequency ion acoustic wave can propagate when the plasmas are cold. 展开更多
关键词 electrostatic wave quantum plasma weakly magnetized
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一只蓝狐
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作者 王霖馨 《初中生辅导》 2015年第25期6-7,共2页
我是一只蓝狐,一只生活在北冰洋沿圈的蓝狐。自从被场主请到这儿来后,我每天夜晚都会听见母亲那凄惨极了的哀叫,那声音一直在我的耳际回荡,陪伴我入梦。我想不通,为什么母亲总在我半睡半醒时静静的走到我身旁,长长的叹气一声。依稀记得... 我是一只蓝狐,一只生活在北冰洋沿圈的蓝狐。自从被场主请到这儿来后,我每天夜晚都会听见母亲那凄惨极了的哀叫,那声音一直在我的耳际回荡,陪伴我入梦。我想不通,为什么母亲总在我半睡半醒时静静的走到我身旁,长长的叹气一声。依稀记得,母亲和我,还有我的几个姐姐被场主那双大手抓进笼子里的时候,我们几个都没有反抗,这里实在太冷了。 展开更多
关键词 蓝狐 衣食无忧 邻居们 我不知道 静色 主带 指导教师 王开
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青花魂
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作者 笑非 《当代江西》 2008年第7期42-43,共2页
生于瓷都制陶世家的李冬明从小就有个梦,梦想老的青花艺术在自己手中发扬光大走向世界。青花瓷历史悠久,唐代时河南省的巩县窑就有原始青花制作,到了元代江西景德镇已能生产装饰精致的产品了。景德镇烧制的青花瓷,以其胎釉精细、静色浓... 生于瓷都制陶世家的李冬明从小就有个梦,梦想老的青花艺术在自己手中发扬光大走向世界。青花瓷历史悠久,唐代时河南省的巩县窑就有原始青花制作,到了元代江西景德镇已能生产装饰精致的产品了。景德镇烧制的青花瓷,以其胎釉精细、静色浓艳、造型多样。 展开更多
关键词 巩县窑 静色 花魂 瓷都 江西景德镇 陶瓷发展史 中国瓷器 工艺美术大师 藏巧于拙 青花大王
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Quantum tunnelling radiation from static and rotating black lenses in five dimensions
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作者 LI HuiLing 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2012年第11期2004-2009,共6页
Black lenses with L(n,1) horizon topology in five dimensions have many unusual properties shared by neither Myers-Perry black holes with event-horizon topology S 3,nor 5-dimensional black rings with event-horizon topo... Black lenses with L(n,1) horizon topology in five dimensions have many unusual properties shared by neither Myers-Perry black holes with event-horizon topology S 3,nor 5-dimensional black rings with event-horizon topology S 2 × S 1.In this work,by constructing appropriate matrices γμ for the general covariant Dirac equation,we further extend the fermion tunnelling method to 5-dimensional static and rotating black lenses.As a result,it is interesting to find as in black hole cases,fermions tunnelling can also result in correct Hawking temperatures for the static and rotating black lenses. 展开更多
关键词 tunnelling radiation static and rotating black lenses Dirac equation Hawking temperatures
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