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Emotional speaker recognition based on prosody transformation 被引量:1
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作者 宋鹏 赵力 邹采荣 《Journal of Southeast University(English Edition)》 EI CAS 2011年第4期357-360,共4页
A novel emotional speaker recognition system (ESRS) is proposed to compensate for emotion variability. First, the emotion recognition is adopted as a pre-processing part to classify the neutral and emotional speech.... A novel emotional speaker recognition system (ESRS) is proposed to compensate for emotion variability. First, the emotion recognition is adopted as a pre-processing part to classify the neutral and emotional speech. Then, the recognized emotion speech is adjusted by prosody modification. Different methods including Gaussian normalization, the Gaussian mixture model (GMM) and support vector regression (SVR) are adopted to define the mapping rules of F0s between emotional and neutral speech, and the average linear ratio is used for the duration modification. Finally, the modified emotional speech is employed for the speaker recognition. The experimental results show that the proposed ESRS can significantly improve the performance of emotional speaker recognition, and the identification rate (IR) is higher than that of the traditional recognition system. The emotional speech with F0 and duration modifications is closer to the neutral one. 展开更多
关键词 emotion recognition speaker recognition F0 transformation duration modification
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Scalable transcoding for video transmission over space-time OFDM systems 被引量:2
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作者 钱团结 孙军 +2 位作者 解蓉 苏鹏程 王嘉 《Journal of Southeast University(English Edition)》 EI CAS 2005年第4期405-410,共6页
A new scheme combining a scalable transcoder with space time block codes (STBC) for an orthogonal frequency division multiplexing (OFDM) system is proposed for robust video transmission in dispersive fading channe... A new scheme combining a scalable transcoder with space time block codes (STBC) for an orthogonal frequency division multiplexing (OFDM) system is proposed for robust video transmission in dispersive fading channels. The target application for such a scalable transcoder is to provide successful access to the pre-encoded high quality video MPEG-2 from mobile wireless terminals. In the scalable transcoder, besides outputting the MPEG-4 fine granular scalability (FGS) bitstream, both the size of video frames and the bit rate are reduced. And an array processing algorithm of layer interference suppression is used at the receiver which makes the system structure provide different levels of protection to different layers. Furthermore, by considering the important level of scalable bitstream, the different bitstreams can be given different level protection by the system structure and channel coding. With the proposed system, the concurrent large diversity gain characteristic of STBC and alleviation of the frequency-selective fading effect of OFDM can be achieved. The simulation results show that the proposed schemes integrating scalable transcoding can provide a basic quality of video transmission and outperform the conventional single layer transcoding transmitted under the random and bursty error channel conditions. 展开更多
关键词 scalable transcoding DOWN-SAMPLING space-time codes orthogonal frequency division multiplexing
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Establishment of a Multiplex PCR System for Detecting Transgenic Ingredients from Citrus 被引量:1
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作者 李政利 彭爱红 +3 位作者 邹修平 何永睿 姚利晓 陈善春 《Agricultural Science & Technology》 CAS 2012年第5期952-957,共6页
[Objective] This study aimed to establish a multiplex PCR system for de- tecting transgenic ingredients from Citrus. [Method] Based on the pBI121 plasmid sequences published in GenBank and actin gene sequence of Citru... [Objective] This study aimed to establish a multiplex PCR system for de- tecting transgenic ingredients from Citrus. [Method] Based on the pBI121 plasmid sequences published in GenBank and actin gene sequence of Citrus, the primers specific to CaMV35S promoter, NOS promoter, NOS terminator and actin gene were designed, to establish a multiple PCR system which could detect four types of sequences. In addition, orthogonal tests were performed to determine the optimal concentrations of all the components in PCR reaction system, as well as the optimal PCR cycle parameters. [Result] The optimal PCR reaction system should contain 2.5μl of 10xPCR buffer, 2.0μl of MgCI2 (25 mmol/L), 2.0 μl of dNTP mixture (2.5 mmol/L of each dNTP), 1.0 μl of actin gene primers (10μmol/L), 1.0μl of 35S promoter primers (10 μmol/L), 1.5 μl of NOS promoter primers (10 μmol/L) and 0.5 μl of NOS terminator primers (10μmol/L), 0.1 μg of template DNA, 1.25 U of Taq DNA polymerase; ddH20 was added to the total reaction system of 25μl. The PCR reaction program consisted of pre-denaturing at 94℃ for 5 min; 31 cycles of denaturing at 94℃ for 30 s, annealing at 64.1℃ for 45 s and extension at 72℃ for 50 s; final extension at 72℃ for 10 min. The reaction system optimized with the orthogonal tests could detect as less as 0.1% transgenic component in the tested samples. [Conclusion] The MPCR detection system established in this study can meet the requirements in theory for detecting the genetically modified ingredients in Citrus or the deep-processed products. 展开更多
关键词 Multiplex PCR Orthogonal test DETECTION Genetically modified ingredients
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ZCT Scheme of Push-Pull Forward Converter 被引量:4
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作者 张方华 王慧贞 严仰光 《Journal of Southeast University(English Edition)》 EI CAS 2002年第4期331-335,共5页
The paper proposes a novel zero current transition (ZCT) push pull forward converter. The auxiliary resonant cell is in parallel with the main circuit and the zero current switching (ZCS) range of the main and the aux... The paper proposes a novel zero current transition (ZCT) push pull forward converter. The auxiliary resonant cell is in parallel with the main circuit and the zero current switching (ZCS) range of the main and the auxiliary switches of the proposed converter are entirely achieved. The resonant capacitor achieves high voltage by operating the auxiliary cell. The auxiliary switch turns on before the main switches turn off, the high voltage of resonant capacitor blanks off the rectifier, and then the curr... 展开更多
关键词 converter/ZCT converter ZCS/ZCT push pull/push pull forward
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Healthy ranges of serum alanine aminotransferase levels in Iranian blood donors 被引量:6
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作者 Mehdi Mohamadnejad Akram Pourshams +6 位作者 Reza Malekzadeh Ashraf Mohamadkhani Afsaneh Rajabiani Ali Ali Asgari Seyed Meysam Alimohamadi Hadi Razjooyan Mansooreh Mamar-Abadi 《World Journal of Gastroenterology》 SCIE CAS CSCD 2003年第10期2322-2324,共3页
AIM: The healthy ranges for serum alanine aminotransferase(ALT) levels are less well studied. The aim of this study was to define the upper limit of normal (ULN) for serum ALT levels, and to assess factors associated ... AIM: The healthy ranges for serum alanine aminotransferase(ALT) levels are less well studied. The aim of this study was to define the upper limit of normal (ULN) for serum ALT levels, and to assess factors associated with serum ALT activity in apparently healthy blood donors. METHODS: A total of 1 939 blood donors were included.ALT measurements were performed for all cases using the same laboratory method. Healthy ranges for ALT levels werecomputed from the population at the lowest risk for liver disease. Univariate and multivariate analyses were performed to evaluate associations between clinical factors and ALT levels.RESULTS: Serum ALT activity was independently associated with body mass index (BMI) and male gender, but not associated with age. Association of ALT with BMI was more prominent in males than in females. Upper limit of normal for non-overweight women (BMI of less than 25) was 34 U/L,and for non-overweight men was 40 U/L.CONCLUSION: Serum ALT is strongly associated with sex and BMI. The normal range of ALT should be defined for male and female separately. 展开更多
关键词 ADOLESCENT ADULT Age Distribution Aged Alanine Transaminase Blood Donors Body Mass Index Chemistry Clinical numerical data CHILD Female Humans Iran Logistic Models Male Middle Aged Reference Values Sex Distribution
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Development of practical postprocessor for 5-axis machine tool with non-orthogonal rotary axes 被引量:13
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作者 JUNG Hyoun-Chul HWANG Jong-Dae +1 位作者 PARK Ki-Beom JUNG Yoon-Gyo 《Journal of Central South University》 SCIE EI CAS 2011年第1期159-164,共6页
In order to develop a practical postprocessor for 5-axis machine tool,the general equations of numerically controlled(NC) data for 5-axis configurations with non-orthogonal rotary axes were exactly expressed by the in... In order to develop a practical postprocessor for 5-axis machine tool,the general equations of numerically controlled(NC) data for 5-axis configurations with non-orthogonal rotary axes were exactly expressed by the inverse kinematics,and a windows-based postprocessor written with Visual Basic was developed according to the proposed algorithm.The developed postprocessor is a general system suitable for all kinds of 5-axis machines with orthogonal and non-orthogonal rotary axes.Through implementation of the developed postprocessor and verification by a cutting simulation and machining experiment,the effectiveness of the proposed algorithm is confirmed.Compatibility is improved by allowing exchange of data formats such as rotational total center position(RTCP) controlled NC data,vector post NC data,and program object file(POF) cutter location(CL) data,and convenience is increased by adding the function of work-piece origin offset.Consequently,a practical post-processor for 5-axis machining is developed. 展开更多
关键词 post-processor 5-axis machining non-orthogonal rotary axes numerically controlled (NC) data CL data
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Does Amplify-and-Forward Cooperative Relay Improve OFDM/OFDMA Ergodic Capacity? 被引量:1
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作者 HUANGFU Wei ZHANG Zhongshan +1 位作者 ZHANG Dandan LONG Keping 《China Communications》 SCIE CSCD 2014年第2期83-89,共7页
The ergodic information rate for Orthogonal Frequency-Division Multiplexing / Orthogonal Frequency-Division Multiple Access with amplify-and-forward (AF) relaying systems in the presence of frequency offsets is eval... The ergodic information rate for Orthogonal Frequency-Division Multiplexing / Orthogonal Frequency-Division Multiple Access with amplify-and-forward (AF) relaying systems in the presence of frequency offsets is evaluated. Unlike previous work, per-subcarrier adaptive power allocation is performed on each relay to optimize the system ergodic information rate. For a given frequency offset and total number of relays M, the AF ergodic information rate is proven to be a monotonically increasing function of α (the ratio of the power allocated to the source node and the total transmit power), implying that the maximum ergodic information rate can be obtained at α=1 (i.e., there is no cooperative relay). Furthermore, the proof of "cooperative relays cannot improve the AF ergodic information rate in a quasi-static wireless channel" is also provided in this letter. 展开更多
关键词 cooperation amplify-ano-forward (AF) ergodic information rate frequency offset Orthogonal Frequency-Division Multiplexing (OFDM) OrthogonalFrequency-Division Multiple Access(OFDMA)
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Mathematical treatment of wave propagation in acoustic waveguides with n curved interfaces 被引量:3
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作者 Jian-xin ZHU Peng LI 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第10期1463-1472,共10页
There are some curved interfaces in ocean acoustic waveguides. To compute wave propagation along the range with some marching methods, a flattening of the internal interfaces and a transforming equation are needed. In... There are some curved interfaces in ocean acoustic waveguides. To compute wave propagation along the range with some marching methods, a flattening of the internal interfaces and a transforming equation are needed. In this paper a local orthogonal coordinate transform and an equation transformation are constructed to flatten interfaces and change the Helmholtz equation as a solvable form. For a waveguide with a flat top, a fiat bottom and n curved interfaces, the coefficients of the transformed Helmholtz equation are given in a closed formulation which can be thought of as an extension of the formal work related to the equation transformation with two curved internal interfaces. In the transformed horizontally stratified waveguide, the one-way reformulation based on the Dirichlet-to-Neumann (DtN) map is then used to reduce the boundary value problem to an initial value problem. Numerical implementation of the resulting operator Riccati equation uses a large range step method to discretize the range variable and a truncated local eigenfunction expansion to approximate the operators. This method is particularly useful for solving long range wave propagation problems in slowly varying waveguides. Furthermore, the method can also be applied to wave propagation problems in acoustic waveguides associated with varied density. 展开更多
关键词 Helmholtz equation Local orthogonal transform Dirichlet-to-Neumarm (DtN) reformulation Marching method Curved interface Multilayer medium
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Diagnostic yield of small bowel capsule endoscopy depends on the small bowel transit time 被引量:10
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作者 Jessie Westerhof Jan J Koornstra +3 位作者 Reinier A Hoedemaker Wim J Sluiter Jan H Kleibeuker Rinse K Weersma 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第13期1502-1507,共6页
AIM: To investigate whether the small bowel transit time (SBTT) influences the diagnostic yield of capsule endoscopy (CE). METHODS: Six hundred and ninety-one consecutive CE procedures collected in a database we... AIM: To investigate whether the small bowel transit time (SBTT) influences the diagnostic yield of capsule endoscopy (CE). METHODS: Six hundred and ninety-one consecutive CE procedures collected in a database were analyzed. SBTT and CE findings were recorded. A running mean for the SBl-I- was calculated and correlated to the diagnostic yield with a Spearman's correlation test. Subgroup anal- yses were performed for the various indications for the procedure. RESULTS: There was a positive correlation between the diagnostic yield and SBT1- (Spearman's rho 0.58, P 〈 0.01). Positive correlations between diagnostic yield and SB-FI-were found for the indication obscure gastro- intestinal bleeding (r = 0.54, P 〈 0.01), for polyposis and carcinoid combined (r = 0.56, P 〈 0.01) and for the other indications (r = 0.90, P 〈0.01), but not for suspected Crohn's disease (r = -0.40) CONCLUSION: The diagnostic yield in small bowel capsule endoscopy is positively correlated with the small bowel transit time. This is true for all indications except for suspected Crohn's disease. 展开更多
关键词 Capsule endoscopy Small bowel transit time Diagnostic yield
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Preliminary in vitro biological evaluation of novel O^6-benzylguanine derivative-precursors of PET tracers for the DNA repair protein AGT
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作者 贺巍巍 刘昭飞 +3 位作者 刘丹 贾兵 王凡 崔育新 《Journal of Chinese Pharmaceutical Sciences》 CAS 2008年第1期70-74,共5页
A series of O6-benzylguanine (O6-BG) derivatives was synthesized, and their in vitro AGT (O^6-Alkylguanine DNA alkyltransferase) inhibitory ability was evaluated by MTT method to investigate the possibility to be ... A series of O6-benzylguanine (O6-BG) derivatives was synthesized, and their in vitro AGT (O^6-Alkylguanine DNA alkyltransferase) inhibitory ability was evaluated by MTT method to investigate the possibility to be promising precursors of PET tracers. O^6--BG and its derivatives, HMBG, MOBG, MOMBG, BABP and PEG, were synthesized from guanine respectively. The AGT inhibitory ability of the compounds were tested by evaluating their effects on increasing sensitivity of HeLa cancer cells to 1,3-bis (2-chloroethyl)-l-nitrosourea (BCNU) with MTT method. Their order of AGT inhibitory activities follows HMBG ≥ O^6-BG ≥ MOBG ≥ MOMBG, whereas the BABP and PEG showed no AGT inhibition activity. HMBG, MOBG and MOMBG would be promising as precursor candidates of PET tracers for tumor imaging. 展开更多
关键词 O6-Benzylguanine derivatives O6-Alkylguanine DNA alkyltransferase MTT Positron emission tomography
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APOPTOSIS OF EPIDIDYMIS EPITHELIUM AND CONTENT OF EPIDIDYMIS SIALIC ACID FOLLOWING TORSED/DETORSED TESTES IN RAT 被引量:1
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作者 赵豫刚 郑新民 +2 位作者 杨志伟 李世文 胡礼泉 《Journal of Shanghai Second Medical University(Foreign Language Edition)》 2004年第2期114-117,共4页
Objective To investigate the apoptosis of epididyrnis epithelium and the change of epididymissialic acid following torsed/detorsed testes. Methods Twenty four adult male Sprague-Dawley rats were subjected to unilatera... Objective To investigate the apoptosis of epididyrnis epithelium and the change of epididymissialic acid following torsed/detorsed testes. Methods Twenty four adult male Sprague-Dawley rats were subjected to unilateral 720 testicular torsion with the duration of 2h and 4h, then repaired. The ischemic epididymis were collected for detecting the content of sialic acid by using spectrophotometry and the apoptosis with TUNEL technique. Results There were no statistically significant difference in the apoptosis of epididymis epithelium [(9.51± 2.78)% vs (6.34±1. 98)%] and the content of epididymis sialic acid(23, 3851 ± 9. 2199mg/mgprot vs 19. 3661 6. 3373mg/mgprot) at 24h between following 2h-torsed/detorsed testes and those of sham group. There were statistically significant difference in the apopotosis of epididymis epithelium[ (46. 81 ±3. 55)% vs (6. 34±1. 98) % ] and the content of epididymis sialic acid (13. 7249±7. 8006mg/mgprot vs 19. 3661±6. 3373mg/mgprot) at 24h between following 4h-torsed/detorsed testes and those of sham group(P <0. 05). Conclusion The results suggest that the sialic acid-secreting-function of epididymis remain normal at 24h following 2h-torsed/detorsed testes, while the apoptosis index of epididymis epithelium do not increase. The epididymis would be injured at 24h following 4h-torsed/detorsed testes, while the apoptosis index increased. 展开更多
关键词 testicular torsion detorsion cell apoptosis sialic acid
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Distribution of the tropical Pacific surface zonal wind anomaly and its relation with two types of El Nio 被引量:1
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作者 汪洋 陈锦年 王宏娜 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2013年第5期1137-1152,共16页
E1 Nino events with an eastern Pacific pattern (EP) and central Pacific pattern (CP) were first separated using rotated empirical orthogonal functions (REOF). Lead/lag regression and rotated singular value decom... E1 Nino events with an eastern Pacific pattern (EP) and central Pacific pattern (CP) were first separated using rotated empirical orthogonal functions (REOF). Lead/lag regression and rotated singular value decomposition (RSVD) analyses were then carried out to study the relation between the surface zonal wind (SZW) anomalies and sea surface temperature (SST) anomalies in the tropical Pacific. A possible physical process for the CP E1 Nifio was proposed. For the EP E1 Nino, strong westerly anomalies that spread eastward continuously produce an anomalous ocean zonal convergence zone (ZCZ) centered on about 165°W. This SZW anomaly pattern favors poleward and eastward Sverdrup transport at the equator. For the CP E1Nino, westerly anomalies and the ZCZ are mainly confined to the western Pacific, and easterly anomalies blow in the eastern Pacific. This SZW anomaly pattern restrains poleward and eastward Sverdrup transport at the equator; however, there is an eastward Sverdrup transport at about 5°N, which favors the wanning of the north-eastern tropical Pacific. It is found that the slowness of eastward propagation of subsurface warm water (partly from the downwelling caused by Ekman convergence and the ZCZ) is due to the slowdown of the undercurrent in the central basin, and vertical advection in the central Pacific may be important in the formation and disappearance of the CP E1 Nifio. 展开更多
关键词 surface zonal wind anomaly CP (central Pacific) E1 Nino rotated empirical orthogonal function rotated singular value decomposition zonal convergence physical process
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BEACON SYNCHRONIZATION TECHNOLOGY FOR “BEIDOU” TERRESTRIAL IMPROVEMENT SYSTEM 被引量:2
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作者 WEIJin-chen TANGJi-qiang SHENFeng 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2005年第2期177-182,共6页
Synchronization is an essential technology in the radio navigation system. The technique for improving the “Beidou” positioning ability is presented through constituting the terrestrial improvement system, and the b... Synchronization is an essential technology in the radio navigation system. The technique for improving the “Beidou” positioning ability is presented through constituting the terrestrial improvement system, and the beacon synchronization of the improvement system with the “Beidou” one-way time transfer model is realized.The direct digital synthesis (DDS) is adopted to generate the pseudo-random code clock having high precision and stability. Meanwhile, the CPLD device is used to design the synchronization pulse picking-up module, the spread spectrum PN code generator and the spread spectrum modulator. Measurement results indicate that the beacon synchronization has the high precision and the stability. 展开更多
关键词 radio navigation system terrestrial improvement system time transfer SYNCHRONIZATION
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A Note of log A≥log B
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作者 高福根 杨长森 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第1期135-139,共5页
In this paper, firstly we shall show some equivalent conditions of A 〉 B 〉 0; secondly by using the results of ours we shall show some characterizations of the chaotic order(i.e., logA≥log B) by norm inequalities.
关键词 chaotic order positive invertible operators Furuta inequality
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Control strategy for pneumatic rotary position servo systems based on feed forward compensation pole-placement self-tuning method 被引量:2
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作者 毛新涛 杨庆俊 +1 位作者 吴晋军 包钢 《Journal of Central South University》 SCIE EI CAS 2009年第4期608-613,共6页
The pneumatic rotary position system, in which an electro-pneumatic proportional flow valve controled a rotary cylinder, was studied, and its mathematical model was built. The model indicated that the controlled pneum... The pneumatic rotary position system, in which an electro-pneumatic proportional flow valve controled a rotary cylinder, was studied, and its mathematical model was built. The model indicated that the controlled pneumatic system had disadvantages such as inherent non-linearity and variations of system parameters with working points. In order to improve the dynamic performance of the system, feed forward compensation self-tuning pole-placement strategy was adopted to place the poles of the system in a desired position in real time, and a recursive least square method with fixed forgetting factors was also used in the parameter estimation. Experimental results show that the steady state error of the pneumatic rotary position system is within 3% and the identified system parameters can be converged in 5 s. Under different loads, the controlled system has an excellent tracking performance and robustness of anti-disturbance. 展开更多
关键词 pneumatic servo system adaptive control parameter identification POLE-PLACEMENT
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Bekenstein-Hawking Cosmological Entropy and Correction Term Corresponding Cosmological Horizon of Rotating and Charged Black String
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作者 ZHAO Ren WU Yue-Qin +1 位作者 ZHANG Li-Chun LI Huai-Fan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第8期264-268,共5页
Utilizing the quantum statistical method and applying the new state density equation motivated by generalized uncertainty principle in quantum gravitaty, we avoid the difficulty in solving wave equation and directly c... Utilizing the quantum statistical method and applying the new state density equation motivated by generalized uncertainty principle in quantum gravitaty, we avoid the difficulty in solving wave equation and directly calculate the partition function of bosonic and fermionic field on the background of rotating and charged black string. Then near the cosmological horizon, entropies of bosonic and fermionic field are calculated on the background of black string. When constant A introduced in generalized uncertainty principle takes a proper value, we derive Bekenstein- Hawking entropy and the correction value corresponding cosmologicaJ horizon on the background of rotating and charged black string. Because we use the new state density equation, in our calculation there are not divergent term and small mass approximation in the original brick-wall method. From the view of quantum statistic mechanics, the correction value to Bekenstein-Hawking entropy of the black string is derived. It makes people deeply understand the correction value to the entropy of the black string cosmological horizon in non-spherical coordinate spacetime. 展开更多
关键词 quantum statistics nonspherical symmetry spacetime generalized uncertainty principle entropy corresponding black string cosmological horizon
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Analysis and application of pseudo-offset method in the converted-wave prestack time migration 被引量:2
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作者 Zhang Liyan Liu Yang 《Applied Geophysics》 SCIE CSCD 2006年第1期18-26,共9页
Pseudo-offset migration (POM) is a new method for prestack time migration of converted waves that improves on equivalent-offset migration (EOM). The mapping of POM is different than EOM but the purpose of the two ... Pseudo-offset migration (POM) is a new method for prestack time migration of converted waves that improves on equivalent-offset migration (EOM). The mapping of POM is different than EOM but the purpose of the two methods is to map the input samples to the common conversion scatter point (CCSP) gathers. This paper introduces the principles of the two migration methods and model parameter sensitivity tests for both POM and EOM. At large offset-to-depth ratios the hyperbolic approximation, the three-term approximation and the double square root (DSR) equation are used to NMO-correct the mapped POM gathers to obtain more accurate migration velocities. These equations were derived and calculated by small pseudo offset. POM is then used to image complex structure and prestack time migration. 展开更多
关键词 converted-wave Pseudo-offset migration equivalent-offset migration time migration NMO correction.
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Optimization of IBRS-2 Cells Culturing Conditions for Cultivation of Porcine Parvovirus N Strain Using Roller Bottle
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作者 卢冰霞 何颖 +10 位作者 赵武 梁家幸 段群棚 蒋冬福 卢敬专 闭炳芬 周英宁 秦毅斌 李斌 苏乾莲 陈忠伟 《Agricultural Science & Technology》 CAS 2017年第5期839-842,共4页
The aim was to optimize the roller bottle culture system of IBRS-2 cells for cultivation of porcine parvovirus (PPV) N strain using a four-factor three-level or- thogonal test (cell culture medium pH value: 7.0, 7... The aim was to optimize the roller bottle culture system of IBRS-2 cells for cultivation of porcine parvovirus (PPV) N strain using a four-factor three-level or- thogonal test (cell culture medium pH value: 7.0, 7.2 and 7.4; inoculation time: 0, 24 and 48 h; inoculation dose: 0.10%, 1.00% and 10.00%; harvest time: 48, 72 and 96 h). The results showed that the optimal conditions were as follows: cell culture medium pH value of 7.2, synchronous inoculation, inoculation dose of 0.10% and culture time of 96 h. Among the four factors, culture time was the most important factor affectina the virulence titer of PPV N strain. 展开更多
关键词 Porcine parvovirus (PPV) Roller bottle culture OPTIMIZATION Orthogonal test
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A Bilinear Backlund Transformation and Lax Pair for a (1+1)-Dimensional Differential-Difference sine-Gordon Equation 被引量:1
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作者 QIAN Xian-Min Hon-Wah Tam 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第3X期487-490,共4页
In this paper, we obtain a 1+1 dimensional integrable differential-difference model for the sine-Gordon equation by Hirota's discretization method. A bilinear Backlund transformation and the associated Lax pair are ... In this paper, we obtain a 1+1 dimensional integrable differential-difference model for the sine-Gordon equation by Hirota's discretization method. A bilinear Backlund transformation and the associated Lax pair are also proposed/or this model. 展开更多
关键词 sine-Gordon equation Hirota's discretization method Backlund transformation Lax pair
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Generalized Maximum Likelihood Noncoherent Block Detection for Decode-and-Forward Relay Systems
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作者 HE Yucheng QIAO Ying ZHOU Lin 《China Communications》 SCIE CSCD 2014年第4期163-171,共9页
This paper considers noncoherent cooperative decode-and-forward(DF) halfduplex multi-branch relay systems.Each relay branch is modeled as a probabilistic transition system at the last hop,and thus it can be considered... This paper considers noncoherent cooperative decode-and-forward(DF) halfduplex multi-branch relay systems.Each relay branch is modeled as a probabilistic transition system at the last hop,and thus it can be considered as a relaying chain comprising multi-hop relays.An approximation to the generalized maximum likelihood(ML) noncoherent block detection is derived for uncoded M-ary modulation in a faded noisy environment.In particular,the derived noncoherent block detection in a noiseless case is equivalent to a multichannel reception with full diversity.Furthermore,the generalized detection is extended specifically to block coded M-ary phase shift keying(MPSK) modulation.For a DF three node relay system using block coded quadrature phase shift keying(QPSK),simulation results are provided to examine the end-to-end error performance of the noncoherent detection with considering the effects of network geometry and power allocation,respectively.It is shown that under a fixed power allocation,a proper relay placement can yield near full diversity for large signal-to-noise ratio. 展开更多
关键词 cooperative communications decode-and- forward MPSK noncoherent detection
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