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浅谈un-、in-、dis-三个英语否定前缀
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作者 郭卫华 田咏俐 《石家庄理工职业学院学术研究》 2012年第Z1期9-10,23,共3页
英语否定前缀在英语派生词缀中占有重要地位,对它们的熟练掌握能够使英语学习者更加高效、精确地学习和积累英语词汇。本文简要分析了英语中最常见的un-、in-、dis-三个否定前缀的构词特点和语义特征,以期能够对英语学习者的词缀学习和... 英语否定前缀在英语派生词缀中占有重要地位,对它们的熟练掌握能够使英语学习者更加高效、精确地学习和积累英语词汇。本文简要分析了英语中最常见的un-、in-、dis-三个否定前缀的构词特点和语义特征,以期能够对英语学习者的词缀学习和词汇积累起到一定的指导作用。 展开更多
关键词 un- in- dis- 否定前缀
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DIS-401数字音频切换器自动解除报警改造实例
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作者 李健 《西部广播电视》 2020年第24期227-230,共4页
海峡广电的DHX AUDIO DIS-401是一款四选一数字音频切换器。该切换器在信号源中断及信号恢复时都会触发报警,并且只能通过手动操作前面板上的“取消报警”按钮才能解除报警。微波信号源在雨雪天或者大风天气时不稳定,会频繁触发DIS-401... 海峡广电的DHX AUDIO DIS-401是一款四选一数字音频切换器。该切换器在信号源中断及信号恢复时都会触发报警,并且只能通过手动操作前面板上的“取消报警”按钮才能解除报警。微波信号源在雨雪天或者大风天气时不稳定,会频繁触发DIS-401报警,当信号恢复时也需要工作人员手动解除报警,严重影响值班人员正常工作。芜湖发射台技术人员通过增加外接电路,在不影响原设备报警触发条件的前提下,实现当所有信号源均恢复正常时DIS-401自动解除报警功能。 展开更多
关键词 音频切换器 dis-401 报警 自动解除 改造
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Contrastive analysis of prefix dis- and un- in English
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作者 李集团 《International English Education Research》 2014年第5期89-91,共3页
English prefix dis- and tin- are commonly surveyed along with some other negative prefixes. However, there are many cases in which prefix dis- and un- can be attached to the same root, causing the difficulty in distin... English prefix dis- and tin- are commonly surveyed along with some other negative prefixes. However, there are many cases in which prefix dis- and un- can be attached to the same root, causing the difficulty in distinguishing the comprehension of the two prefixes' semantic roles. Considering this issue, this paper endeavors to clarify the respective morphological processes and explain their specific semantic roles. 展开更多
关键词 dis- un- morphological process semantic role
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Research Progress on MEF2B Gene in Human and Animals
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作者 马晓萌 张莉 杜立新 《Agricultural Science & Technology》 CAS 2016年第11期2477-2482,共6页
Myocyte enhancer factor 2B (MEF2B) gene belongs to myocyte enhancer factor 2 (MEF2) gene family. They are all widely expressed in muscle and nerve tissues of human and animals. MEF2B plays an important role in the... Myocyte enhancer factor 2B (MEF2B) gene belongs to myocyte enhancer factor 2 (MEF2) gene family. They are all widely expressed in muscle and nerve tissues of human and animals. MEF2B plays an important role in the growth of muscle, development and differentiation of nerve system and liver fibrosis. This re- view mainly focused on the structural characteristics, tissue distribution, biological functions and research progress of MEF2B gene in human and animals. 展开更多
关键词 Myocyte enhancer factor 2B (MEF2B) Biological functions Tissue dis- tribution Research progress
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Breeding and Application of Japonica CMS Line Yangfujing 7A with Fine Grain Quality, Disease Resistance and High Combining Ability in Rice
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作者 周根友 夏华 《Agricultural Science & Technology》 CAS 2017年第2期377-379,共3页
Yangfujing 7A, derived from the cross between Xu 9201A and Yangfujing 7 and its successive backcrosses, is a BT-type japonica CMS line developed by the Agricultural Institute of Riparian Region of Jiangsu Province. It... Yangfujing 7A, derived from the cross between Xu 9201A and Yangfujing 7 and its successive backcrosses, is a BT-type japonica CMS line developed by the Agricultural Institute of Riparian Region of Jiangsu Province. It shows good integrat- ed characteristics, stable male sterility, good flowering habits, high out crossing rate, strong disease resistance, fine grain quality (reaching the 1st class of national standards for fine quality rice) and high combining ability. In 2012, it was technically identified in Jiangsu Province. Its F1 hybrid combination Tongyoujingl (Yangfujing 7 A/R98), showing high yield and good grain quality, was registered and released to commercial production by Jiangsu Crop Variety Appraisal Committee in 2013. 展开更多
关键词 Japonica hybrid rice CMS line Yangfujing 7A Fine grain quality dis- ease resistance BREEDING
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油井水泥分散剂DIS─3的合成及应用
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作者 赵林 董文轩 《江汉石油学院学报》 CSCD 北大核心 1998年第2期54-57,共4页
介绍了一种新型油井水泥分散剂DIS3的合成,室内实验考察了DIS-3对水泥浆性能的影响。结果表明:在DIS3的加量为0.4%~0.6%(基于干水泥质量)时,可使水泥浆的流变性得到明显的改善,且与其它油井水泥外加剂(如... 介绍了一种新型油井水泥分散剂DIS3的合成,室内实验考察了DIS-3对水泥浆性能的影响。结果表明:在DIS3的加量为0.4%~0.6%(基于干水泥质量)时,可使水泥浆的流变性得到明显的改善,且与其它油井水泥外加剂(如降滤失剂和缓凝剂)的配伍性良好,加有DIS3的水泥浆的各项指标均能满足现场固井施工要求。另外,还报道了DIS3在江汉油田3口井固井中的使用效果。 展开更多
关键词 固井 油井 水泥分散剂 dis-3 合成
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ANTI-PLANE SHEAR WAVES SCATTERING FROM A PARTIALLY DEBONDED MAGNETO-ELECTRO-ELASTIC CIRCULAR CYLINDRICAL INHOMOGENEITY 被引量:7
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作者 DuJianke ShenYapeng TianWeiping 《Acta Mechanica Solida Sinica》 SCIE EI 2004年第1期1-11,共11页
This article presents an analysis of the scattering of anti-plane shear waves from a single cylindrical inhomogeneity partially bonded to an unbounded magneto-electro-elastic matrix. The magneto-electric permeable bou... This article presents an analysis of the scattering of anti-plane shear waves from a single cylindrical inhomogeneity partially bonded to an unbounded magneto-electro-elastic matrix. The magneto-electric permeable boundary conditions are adopted. The crack opening displacement is represented by Chebyshev polynomials and a system of equations is derived and solved for the unknown coefficients. Some examples are calculated and the results are illustrated. The results show that the COD increases when the piezomagnetic coefficient of the inhomogeneity bonded to the piezoelectric matrix becomes larger, and that the COD decreases when the piezomagnetic coefficient of the matrix with the piezoelectric inhomogeneity increases. 展开更多
关键词 SH waves SCATTERING magneto-electro-elasticity INHOMOGENEITY crack opening dis- placement
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Role of on-board discharge in shock wave drag reduction and plasma cloaking 被引量:6
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作者 邱孝明 唐德礼 +2 位作者 孙爱萍 刘万东 曾学军 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第1期186-192,共7页
In the present paper, a physical model is proposed for reducing the problem of the drag reduction of an attached bow shock around the nose of a high-speed vehicle with on-board discharge, to the problem of a balance b... In the present paper, a physical model is proposed for reducing the problem of the drag reduction of an attached bow shock around the nose of a high-speed vehicle with on-board discharge, to the problem of a balance between the magnetic pressure and gas pressure of plane shock of a partially ionized gas consisting of the environmental gas around the nose of the vehicle and the on-board discharge-produced plasma. The relation between the shock strength and the discharge-induced magnetic pressure is studied by means of a set of one-fluid, hydromagnetic equations reformed for the present purpose, where the discharge-induced magnetic field consists of the electron current (produced by the discharge)-induced magnetic field and the partially ionized gas flow-induced one. A formula for the relation between the above parameters is derived. It shows that the discharge-induced magnetic pressure can minimize the shock strength, successfully explaining the two recent experimental observations on attached bow shock mitigation and elimination in a supersonic flow during on-board discharge [Phys. Plasmas 9 (2002) 721 and Phys. Plasmas 7 (2000) 1345]. In addition, the formula implies that the shock elimination leaves room for a layer of higher-density plasma rampart moving around the nose of the vehicle, being favourable to the plasma radar cloaking of the vehicle. The reason for it is expounded. 展开更多
关键词 attached bow shock and magnetohydrodynamic (MHD) drag reduction on-board dis- charges plasma cloaking MHD and fluid equation
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Cancer risk in IBD: How to diagnose and how to manage DALM and ALM 被引量:7
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作者 Helmut Neumann Michael Vieth +2 位作者 Cord Langner Markus F Neurath Jonas Mudter 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第27期3184-3191,共8页
The risk of developing neoplasia leading to colorectal cancer is significantly increased in ulcerative colitis (UC) and most likely in Crohn's disease. Several endoscopic surveillance strategies have been implemen... The risk of developing neoplasia leading to colorectal cancer is significantly increased in ulcerative colitis (UC) and most likely in Crohn's disease. Several endoscopic surveillance strategies have been implemented to identify these lesions. The main issue is that colitisassociated neoplasms often occurs in flat mucosa, often being detected on taking random biopsies rather than by identification of these lesions via endoscopic imaging. The standard diagnostic procedure in long lasting UC is to take four biopsies every 10 cm. Image enhancement methods, such as chromoendoscopy and virtual histology using endomicroscopy, have greatly im- proved neoplasia detection rates and may contribute toreduced random biopsies by taking targeted "smart" biopsies. Chromoendoscopy may effectively be performed by experienced endoscopists for routine screening of UC patients. By contrast, endomicroscopy is often only available in selected specialized endoscopic centers. Importantly, advanced endoscopic imaging has the poten- tial to increase the detection rate of neoplasia whereas the interplay between endoscopic experience and interpretation of histological biopsy evaluation allows the physician to make a proper diagnosis and to find the appropriate therapeutic approach. Colitis-associated intraepithelial neoplasms may occur in flat mucosa of endoscopically normal appearance or may arise as dysplasia-associated lesion or mass (DALM), which may be indistinguishable from sporadic adenomas in healthy or non-colitis mucosa [adenoma-like mass (ALM)]. The aim of this review was to summarize endoscopic and histological characteristics of DALM and ALM in the context of therapeutic procedures. 展开更多
关键词 Inflammatory bowel disease Crohn’s dis- ease Endoscopy Colitis Dysplasia-associated lesion or mass Adenoma-like mass ENDOMICROSCOPY Ulcerative colitis ENDOMICROSCOPY Confocal laser endomicroscopy Probe-based confocal laser endomicroscopy Integrated confocal laser endomicroscopy Endoscope-based confocal laser endomicroscopy Narrow band imaging CHROMOENDOSCOPY Cancer DYSPLASIA
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ANTI-PLANE SHEAR CRACK IN A FUNCTIONALLY GRADIENT PIEZOELECTRIC MATERIAL 被引量:2
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作者 Hu Keqiang Zhong Zheng Jin Bo 《Acta Mechanica Solida Sinica》 SCIE EI 2002年第2期140-148,共9页
The main objective of this paper is to study the singular natureof the crack-tip stress and electric displacement field in afunctionally gradient piezoelectric medium having materialcoefficients with a discontinuous d... The main objective of this paper is to study the singular natureof the crack-tip stress and electric displacement field in afunctionally gradient piezoelectric medium having materialcoefficients with a discontinuous derivative. The problem isconsidered for the simplest possible loading and geometry, namely,the anti-plane shear stress and electric displacement in -plane oftwo bonded half spaces in which the crack is parallel to theinterface. 展开更多
关键词 functionally gradient material piezoelectric material stress intensityfactors electric dis- placement intensity factors
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Does immunohistochemical staining have a clinical impact in early gastric cancer conducted endoscopic submucosal dissection? 被引量:6
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作者 Seong Ran Jeon Joo Young Cho +5 位作者 Gene Hyun Bok Tae Hee Lee Hyun Gun Kim Won Young Cho So Young Jin Yeon Soo Kim 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第33期4578-4584,共7页
AIM: To evaluate clinicopathologic parameters and the clinical significance related lymphovascular invasion (LVI) by immunohistochemical staining (IHCS) in endoscopic submucosal dissection (ESD). METHODS: Between May ... AIM: To evaluate clinicopathologic parameters and the clinical significance related lymphovascular invasion (LVI) by immunohistochemical staining (IHCS) in endoscopic submucosal dissection (ESD). METHODS: Between May 2005 and May 2010, a total of 348 lesions from 321 patients (mean age 63 ± 10 years, men 74.6%) with early gastric cancer (EGC) who met indication criteria after ESD were analyzed retrospectively. The 348 lesions were divided into the absolute (n = 100, differentiated mucosal cancer without ulcer ≤ 20 mm) and expanded (n = 248) indica-tion groups after ESD. The 248 lesions were divided into four subgroups according to the expanded ESD indication. The presence of LVI was determined by factor Ⅷ-related antigen and D2-40 assessment. We compared LVI IHCS-negative group with LVI IHCSpositive in each group. RESULTS: LVI by hematoxylin-eosin staining (HES) and IHCS were all negative in the absolute group, while was observed in only the expanded groups. The positive rate of LVI by IHCS was higher than that of LVI by HES (n = 1, 0.4% vs n = 11, 4.4%, P = 0.044). LVI IHCS-positivity was observed when the cancer invaded to the mucosa 3 (M3) or submucosa 1 (SM1) levels, with a predominance of 63.6% in the subgroup that included only SM1 cancer (P < 0.01). In a univariate analysis, M3 or SM1 invasion by the tumor was significantly associated with a higher rate of LVI by IHCS, but no factor was significant in a multivariate analysis. There were no cases of tumor recurrence or metastasis during the median 26 mo follow-up. CONCLUSION: EGCs of the absolute group are immunohistochemically stable. The presence of LVI may be carefully examined by IHCS in an ESD expanded indication group with an invasion depth of M3 or greater. 展开更多
关键词 Gastric cancer Endoscopic submucosal dis- section Immunohistochemical staining Lymphovascu- lar invasion Depth
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A two-step rectification algorithm for airborne linear images with POS data
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作者 庹红娅 刘允才 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第6期492-496,共5页
Rectification for airborne linear images is an indispensable preprocessing step. This paper presents in detail a two-step rectification algorithm. The first step is to establish the model of direct georeference positi... Rectification for airborne linear images is an indispensable preprocessing step. This paper presents in detail a two-step rectification algorithm. The first step is to establish the model of direct georeference position using the data provided by the Po- sitioning and Orientation System (POS) and obtain the mathematical relationships between the image points and ground reference points. The second step is to apply polynomial distortion model and Bilinear Interpolation to get the final precise rectified images. In this step, a reference image is required and some ground control points (GCPs) are selected. Experiments showed that the final rectified images are satisfactory, and that our two-step rectification algorithm is very effective. 展开更多
关键词 Airborne linear image POS data Two-step rectification algorithm Direct georeference position Polynomial dis- tortion model
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Modelling of Ar-Hg Electrodeless Lamps
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作者 杨深 石挺 +1 位作者 刘洋 陈育明 《Plasma Science and Technology》 SCIE EI CAS CSCD 2012年第2期147-151,共5页
A self-consistent model of high-frequency electrodeless lamps with internM coils is developed. Radial distributions of the plasma parameters are obtained. Mercury lines with wavelength of 435.8 nm and 365 nm are measu... A self-consistent model of high-frequency electrodeless lamps with internM coils is developed. Radial distributions of the plasma parameters are obtained. Mercury lines with wavelength of 435.8 nm and 365 nm are measured to testify the model. Based on the model, the population of resonance state 63p1 of mercury in dependence on the argon pressure and driving frequency is calculated. It is shown that the population of 63p1 of mercury is larger when the argon pressure is between 26.6 Pa and 53.2 Pa. Meanwhile the driving frequency has little influence on the population of 63P1. 展开更多
关键词 electrodeless lamp inductive coupled plasma (ICP) SIMULATION Ar-Hg dis- charge
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Dynamics of cantilever plates and its hybrid vibration control
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作者 Bo Ni Chao Hu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2013年第5期738-748,共11页
Applying Lagrange-Germain's theory of elas- tic thin plates and Hamiltonian formulation, the dynamics of cantilever plates and the problem of its vibration control are studied, and a general solution is finally given... Applying Lagrange-Germain's theory of elas- tic thin plates and Hamiltonian formulation, the dynamics of cantilever plates and the problem of its vibration control are studied, and a general solution is finally given. Based on Hamiltonian and Lagrangian density function, we can obtain the flexural wave equation of the plate and the relationship between the transverse and the longitudinal eigenvalues. Based on eigenfunction expansion, dispersion equations of propagation mode of cantilever plates are deduced. By satisfying the boundary conditions of cantilever plates, the natural frequencies of the cantilever plate structure can be given. Then, analytic solution of the problem in plate structure is obtained. An hybrid wave/mode control approach, which is based on both independent modal space control and wave control methods, is described and adopted to analyze the active vibration control of cantilever plates. The low-order (controlled by modal control) and the high-order (controlled by wave control) frequency response of plates are both improved. The control spillover is avoided and the robustness of the system is also improved. Finally, simulation results are analyzed and discussed. 展开更多
关键词 Cantilever plate Hamiltonian formulism - dis- persion equations Modal control Elastic wave control - Hybrid control
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英语中几个表示否定意义的前缀及其区别
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作者 龙和文 《英语学习》 2000年第2期44-45,共2页
在英语中,有一些表示否定意义的前缀,在表示否定意义的时候,它们的用法基本相同,可译成汉语"非"、"无"、"不(是)"、"未"等。但这些前缀的来源以及接在后面的词有一定的差别。此外,除了表示否... 在英语中,有一些表示否定意义的前缀,在表示否定意义的时候,它们的用法基本相同,可译成汉语"非"、"无"、"不(是)"、"未"等。但这些前缀的来源以及接在后面的词有一定的差别。此外,除了表示否定意义外,它们各自还可表示其他的意义。下面分别作简单介绍。 展开更多
关键词 英语 语法 否定词缀 前缀 un- non- dis- in-
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Up and Down Expression of Androgen Receptor, Estrogen Receptor beta and Platelet Derived Growth Factor beta by Testosterone in Aortic Vascular Smooth Muscle Tissues
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作者 吴赛珠 吕红松 +5 位作者 周可祥 孙飞 马瑞 郑华 隗和明 容志毅 《South China Journal of Cardiology》 CAS 2004年第2期116-122,共7页
Objectives To investigate the effects of testosterone enanthate (TE) on serum lip- ids and lipoproteins metabolism and the expression of androgen receptor (AR) , estrogen receptor beta ( ER - β) and platelet derived ... Objectives To investigate the effects of testosterone enanthate (TE) on serum lip- ids and lipoproteins metabolism and the expression of androgen receptor (AR) , estrogen receptor beta ( ER - β) and platelet derived growth factor beta ( PDGFR - β) in aortic vascular smooth muscle tissues (VSMTs). Methods Forty aged male rats were ran- domly divided into 4 groups, group A (placebo group) , group B (2. 5 mg/kg intramuscular injection of TE once a week ) , group C (5.0 mg/kg intramuscular injection of TE once a week ) , group D ( 10. 0 mg/kg intramus- cular injection of TE once a week). All animals were fed freely during 16 - week treatment periods. The ex- pression of AR ,ER - βand PDGFR - β were studied by Western bolt. Results Average serum LDL - C was lower in group D than that in group A ( p < 0. 01 ). Compared with the other groups, average serum TC was also lower in group D (p <0. 05). AR expression in aortic vascular smooth muscle tissues could be regulated by TE: 99.50 ±21.74, 125.38 ±28.68 and 101.98 ± 15.42 for TE concentrations at 2.5 mg/kg, 5.0 mg/kg and 10.0 mg/kg, respectively , the expression of ER - β could be regulated by TE: 92. 34 ± 18. 68, 47. 72 ± 18.12, 82.13 ±23.50, and the expression of PDGFR - β could be regulated as well by TE: 219.70 ±45. 59, 50.16 ±9. 72, 125.36 ±15. 74(Data for AR ,ER-β and PDGFR - β protein band intensity were expressed with x ± s, with control group taken as 100 ).Conclusions This study indicates that androgens have significant effects on serum lipids and lipoprotein metabolism. Testosterone enanthate at 5. 0 mg/kg can stimulate the expression of AR, but inhibite the expres- sion of PDGFR. Testosterone enanthate at the concen- trations of 5. 0 mg/kg and 10. 0 mg/kg can inhibite the expression of ER - β. 展开更多
关键词 androgen receptor platelet de- rived growth factor estrogen coronary heart dis- ease aortic vascular smooth muscle testosterone
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A priori error estimates of finite volume element method for hyperbolic optimal control problems 被引量:5
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作者 LUO XianBing CHEN YanPing HUANG YunQing 《Science China Mathematics》 SCIE 2013年第5期901-914,共14页
In this paper,optimize-then-discretize,variational discretization and the finite volume method are applied to solve the distributed optimal control problems governed by a second order hyperbolic equation.A semi-discre... In this paper,optimize-then-discretize,variational discretization and the finite volume method are applied to solve the distributed optimal control problems governed by a second order hyperbolic equation.A semi-discrete optimal system is obtained.We prove the existence and uniqueness of the solution to the semidiscrete optimal system and obtain the optimal order error estimates in L ∞(J;L 2)-and L ∞(J;H 1)-norm.Numerical experiments are presented to test these theoretical results. 展开更多
关键词 second order hyperbolic equation optimal control problems finite volume element method dis- tributed control variational discretization
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否定前缀小议
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作者 黄晓萍 《伊犁教育》 2005年第3期30-31,共2页
我们承认否定前缀un-、in-和dis-有否定意义的同时,实际上它还存在许多不全表示否定的意思。通过文中的比较分析,说明根据否定词缀增加词汇量无疑是一种有效途径。但由于有许多容易产生误解的地方,切忌望“缀”生义,有否定前缀的单... 我们承认否定前缀un-、in-和dis-有否定意义的同时,实际上它还存在许多不全表示否定的意思。通过文中的比较分析,说明根据否定词缀增加词汇量无疑是一种有效途径。但由于有许多容易产生误解的地方,切忌望“缀”生义,有否定前缀的单词也不完全表示否定。一定要认真对待之。 展开更多
关键词 un- in- dis-
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