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Research on Total Electric Field Prediction Method of Ultra-High Voltage Direct Current Transmission Line Based on Stacking Algorithm
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作者 Yinkong Wei Mucong Wu +3 位作者 Wei Wei Paulo R.F.Rocha Ziyi Cheng Weifang Yao 《Computer Systems Science & Engineering》 2024年第3期723-738,共16页
Ultra-high voltage(UHV)transmission lines are an important part of China’s power grid and are often surrounded by a complex electromagnetic environment.The ground total electric field is considered a main electromagn... Ultra-high voltage(UHV)transmission lines are an important part of China’s power grid and are often surrounded by a complex electromagnetic environment.The ground total electric field is considered a main electromagnetic environment indicator of UHV transmission lines and is currently employed for reliable long-term operation of the power grid.Yet,the accurate prediction of the ground total electric field remains a technical challenge.In this work,we collected the total electric field data from the Ningdong-Zhejiang±800 kV UHVDC transmission project,as of the Ling Shao line,and perform an outlier analysis of the total electric field data.We show that the Local Outlier Factor(LOF)elimination algorithm has a small average difference and overcomes the performance of Density-Based Spatial Clustering of Applications with Noise(DBSCAN)and Isolated Forest elimination algorithms.Moreover,the Stacking algorithm has been found to have superior prediction accuracy than a variety of similar prediction algorithms,including the traditional finite element.The low prediction error of the Stacking algorithm highlights the superior ability to accurately forecast the ground total electric field of UHVDC transmission lines. 展开更多
关键词 DC transmission line total electric field effective data multivariable outliers LOF algorithm Stacking algorithm
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Algorithms and statistical analysis for linear structured weighted total least squares problem
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作者 Jian Xie Tianwei Qiu +2 位作者 Cui Zhou Dongfang Lin Sichun Long 《Geodesy and Geodynamics》 EI CSCD 2024年第2期177-188,共12页
Weighted total least squares(WTLS)have been regarded as the standard tool for the errors-in-variables(EIV)model in which all the elements in the observation vector and the coefficient matrix are contaminated with rand... Weighted total least squares(WTLS)have been regarded as the standard tool for the errors-in-variables(EIV)model in which all the elements in the observation vector and the coefficient matrix are contaminated with random errors.However,in many geodetic applications,some elements are error-free and some random observations appear repeatedly in different positions in the augmented coefficient matrix.It is called the linear structured EIV(LSEIV)model.Two kinds of methods are proposed for the LSEIV model from functional and stochastic modifications.On the one hand,the functional part of the LSEIV model is modified into the errors-in-observations(EIO)model.On the other hand,the stochastic model is modified by applying the Moore-Penrose inverse of the cofactor matrix.The algorithms are derived through the Lagrange multipliers method and linear approximation.The estimation principles and iterative formula of the parameters are proven to be consistent.The first-order approximate variance-covariance matrix(VCM)of the parameters is also derived.A numerical example is given to compare the performances of our proposed three algorithms with the STLS approach.Afterwards,the least squares(LS),total least squares(TLS)and linear structured weighted total least squares(LSWTLS)solutions are compared and the accuracy evaluation formula is proven to be feasible and effective.Finally,the LSWTLS is applied to the field of deformation analysis,which yields a better result than the traditional LS and TLS estimations. 展开更多
关键词 linear structured weighted total least SQUARES ERRORS-IN-VARIABLES Errors-in-observations Functional modelmodification Stochastic model modification Accuracyevaluation
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A Total Dose Radiation Hardened PDSOI CMOS 3-Line to 8-Line Decoder
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作者 刘梦新 韩郑生 +3 位作者 李多力 刘刚 赵超荣 赵发展 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第6期1036-1039,共4页
The first domestic total dose hardened 2μm partially depleted silicon-on-insulator (PDSOI) CMOS 3-line to 8- line decoder fabricated in SIMOX is demonstrated. The radiation performance is characterized by transisto... The first domestic total dose hardened 2μm partially depleted silicon-on-insulator (PDSOI) CMOS 3-line to 8- line decoder fabricated in SIMOX is demonstrated. The radiation performance is characterized by transistor threshold voltage shifts,circuit static leakage currents,and I-V curves as a function of total dose up to 3× 10^5rad(Si). The worst case threshold voltage shifts of the front channels are less than 20mV for nMOS transistors at 3 × 10^5rad(Si) and follow-up irradiation and less than 70mV for the pMOS transistors. Furthermore, no significant radiation induced leakage currents and functional degeneration are observed. 展开更多
关键词 PDSOI DECODER total dose RADIATION
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Comparison of totally laparoscopic total gastrectomy using an endoscopic linear stapler with laparoscopic-assisted total gastrectomy using a circular stapler in patients with gastric cancer: a single-center experience 被引量:27
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作者 Chung Sik Gong Byung Sik Kim Hee Sung Kim 《World Journal of Gastroenterology》 SCIE CAS 2017年第48期8553-8561,共9页
AIM To evaluate the safety and efficacy of totally laparoscopic total gastrectomy(TLTG) with esophagojejunostomy using a linear stapler compared with laparoscopic-assisted total gastrectomy(LATG) using a circular stap... AIM To evaluate the safety and efficacy of totally laparoscopic total gastrectomy(TLTG) with esophagojejunostomy using a linear stapler compared with laparoscopic-assisted total gastrectomy(LATG) using a circular stapler in gastric cancer patients.METHODS We retrospectively reviewed 687 patients who underwent laparoscopic total gastrectomy for gastric cancer at a single institution from August 2008 to August 2014. The patients were divided into two groups according to the type of operation: 421 patients underwent TLTG and 266 underwent LATG. Clinicopathologic characteristics and surgical outcomes in the two groups were compared and analyzed.RESULTS The TLTG group had higher mean ages at the time of operation(57.78 ± 11.20 years and 55.69 ± 11.96 years,P = 0.020) and more histories of abdominal surgery(20.2% and 12.4%,P = 0.008) compared with the LATG group. Surgical outcomes such as intraoperative and postoperative transfusions,combined operations,pain scores and administration of analgesics,and complications were similar between the two groups. However,compared with the LATG group,the TLTG group required a shorter operation time(149 min vs 170 min,P < 0.001),had lower postoperative hematocrit change(3.49% vs 4.04%,P = 0.002),less intraoperative events(3.1% vs 10.2%,P < 0.001),less intraoperative anastomosis events(2.4% vs 7.1%,P = 0.003),faster postoperative recovery such as median time to first flatus(3.30 d vs 3.60 d,P < 0.001),faster median commencement of soft diet(4.30 d vs 4.60 d,P < 0.001) and shorter length of postoperative hospital stay(6.75 d vs 7.02 d,P = 0.005). CONCLUSION The intracorporeal method for reconstruction of esophagojejunostomy using a linear stapler may be considered a feasible procedure comparing with extracorporeal anastomosis using circular stapler because TLTG is simpler and more straightforward than LATG. Therefore,TLTG can be recommended as an appropriate procedure for gastric cancer. 展开更多
关键词 totally LAPAROSCOPIC total GASTRECTOMY LAPAROSCOPIC-ASSISTED total GASTRECTOMY GASTRIC cancer
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Image reconstruction based on total-variation minimization and alternating direction method in linear scan computed tomography 被引量:6
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作者 张瀚铭 王林元 +3 位作者 闫镔 李磊 席晓琦 陆利忠 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第7期582-589,共8页
Linear scan computed tomography (LCT) is of great benefit to online industrial scanning and security inspection due to its characteristics of straight-line source trajectory and high scanning speed. However, in prac... Linear scan computed tomography (LCT) is of great benefit to online industrial scanning and security inspection due to its characteristics of straight-line source trajectory and high scanning speed. However, in practical applications of LCT, there are challenges to image reconstruction due to limited-angle and insufficient data. In this paper, a new reconstruction algorithm based on total-variation (TV) minimization is developed to reconstruct images from limited-angle and insufficient data in LCT. The main idea of our approach is to reformulate a TV problem as a linear equality constrained problem where the objective function is separable, and then minimize its augmented Lagrangian function by using alternating direction method (ADM) to solve subproblems. The proposed method is robust and efficient in the task of reconstruction by showing the convergence of ADM. The numerical simulations and real data reconstructions show that the proposed reconstruction method brings reasonable performance and outperforms some previous ones when applied to an LCT imaging problem. 展开更多
关键词 linear scan CT image reconstruction total variation alternating direction method
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The Ability of Baseline Triglycerides and Total Cholesterol Concentrations to Predict Incidence of Type 2 Diabetes Mellitus in Chinese Men and Women:A Longitudinal Study in Qingdao, China 被引量:8
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作者 CUI Jing MA Ping +6 位作者 SUN Jian Ping Zulqamain Baloch YIN Fan XIN Hua Lei REN Jie TAN Ji Bin WANG Bing Ling 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2019年第12期905-913,共9页
Objectives The purpose of this study was to assess the association between triglycerides(TG),total cholesterol(TC)at baseline,and type 2 diabetes mellitus(T2DM)incidence in a general Chinese population.Further,it aime... Objectives The purpose of this study was to assess the association between triglycerides(TG),total cholesterol(TC)at baseline,and type 2 diabetes mellitus(T2DM)incidence in a general Chinese population.Further,it aimed to evaluate the ability of TG and TC to predict T2DM incidence.Methods Qingdao Diabetes Prevention Program participants recruited between 2006 and 2009 were followed up in 2012–2015.TG,TC,and T2DM status were measured.Cox proportional hazards models were used to estimate the association between TG,TC,and T2DM incidence.The receiver operating characteristic(ROC)curve was used to evaluate the ability of TG and TC to identify T2DM participants.Results The incidence of T2DM significantly increased with TG in women and TC in both men and women(Ptrend<0.05).Univariate Cox regression indicated that higher TG{borderline high TG[hazards ratio(HR):2.05;95%confidence interval(CI):1.40,3.00]and hypertriglyceridemia[HR:2.64;95%CI:1.68,4.15]}and TC[hypercholesterolemia(HR:2.05;95%CI:1.43,2.95)]were significantly associated with increased risk of T2DM incidence in women but not in men.Multivariate Cox regression showed that hypertriglyceridemia in women(HR:1.78,95%CI:1.07,2.97),borderline high TC in men(HR:1.61,95%CI:1.04,2.48),and hypercholesterolemia in women(HR:1.68,95%CI:1.81,2.61)had a higher significant risk of T2DM incidence.The optimal cutoff values of TG were>1.15 and>1.23 mmol/L in men and women,respectively.For TC,they were>5.17 and>5.77 mmol/L in men and women,respectively.The area under the ROCs of TG and TC were 0.54(0.51–0.57)and 0.55(0.52–0.58),respectively,in men,and 0.60(0.58–0.62)and 0.59(0.56–0.61),respectively,in women.Conclusion Elevated TG and TC were risk factors for T2DM incidence.However,no predictive capacity was found for both factors to identify T2DM incidence in Chinese men and women.Hence,TG and TC levels in both Chinese men and women might be used for decreasing the incidence of T2DM but no clinical predictive capacity for T2DM. 展开更多
关键词 TRIGLYCERIDES total cholesterol Adult onset type 2 diabetes mellitus
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Maximal and total skew information for a two-qubit system using nonlinear interaction models 被引量:7
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作者 孙红贵 刘万芳 李春杰 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第9期37-43,共7页
Maximal and total skew information is studied. For symmetric pure states of two-qubit, they are closely related to the linear entropy, the concurrence, and the spin squeezing parameter. For a two-qubit system implemen... Maximal and total skew information is studied. For symmetric pure states of two-qubit, they are closely related to the linear entropy, the concurrence, and the spin squeezing parameter. For a two-qubit system implemented in three nonlinear interaction models with an external field, we give the exact state vectors and the expectation value (Sz) at any time t. Based on (Sz)2, we give the maximal and the total skew information and a condition in which the maximal and the total skew information can reach 1 and 2, respectively. 展开更多
关键词 maximal and total Wigner-Yanase skew information nonlinear interaction models two-qubit system
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Maximal and total skew information of three-qubit system obtained using nonlinear interaction models 被引量:6
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作者 Sun Hong-Gui Liu Wan-Fang +1 位作者 Zhang Li-Hua Li Chun-Jie 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第1期52-61,共10页
Both the maximal and the total skew information have been studied. For a three-qubit system implemented in three nonlinear interaction models, we give the exact state vector at any time t. Beused on this, we give the ... Both the maximal and the total skew information have been studied. For a three-qubit system implemented in three nonlinear interaction models, we give the exact state vector at any time t. Beused on this, we give the maximal and the total skew information. It is found that they have the same form and their evolution periods are dependent on the energy difference between the ground state and the second excited state in these models. The maximal skew information is always in the (Sx, Sv) plane. We give the condition for the occurrence of IGHZ}sy, in which they can reach the extreme values of 9/4 and 15/4, respectively. In three different decoherence channels, two kinds of information and the concurrence are calculated. We find that the phenomenon of the concurrence of sudden death occurs, but the above two kinds of information do not die suddenly. In the phase-damping channel, the two kinds of information will not be lost completely. 展开更多
关键词 maximal and total Wigner-Yanase skew information nonlinear interaction models three-qubit system three decoherenee channels
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Observation of Insulin Exocytosis by a Pancreatic β Cell Line with Total Internal Reflection Fluorescence Microscopy 被引量:7
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作者 Zhao-ying Fu Ya-ping Wang Yu Chen 《Chinese Medical Sciences Journal》 CAS CSCD 2011年第1期60-63,共4页
INSULIN secretion was traditionally measured with biochemical and immunological methods such as enzyme linked immunosorbant assay and radioimmunoassay. However, these methods can only tell the amount of insulin secret... INSULIN secretion was traditionally measured with biochemical and immunological methods such as enzyme linked immunosorbant assay and radioimmunoassay. However, these methods can only tell the amount of insulin secreted; they give no information about the secretion process or mechanism of exocytosis. In recent years, an imaging technique known as total internal reflection fluorescence (TIRF) microscopy has been employed to study insulin secretion. 展开更多
关键词 total internal reflection fluorescence microscopy EXOCYTOSIS INSULIN KISS-AND-RUN
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First total synthesis of (±)-trolline 被引量:1
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作者 Qiu Qin He Chao Mei Liu Ke Li 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第6期651-652,共2页
Trolline, a new bioactive alkaloid was isolated in 2004. We reported herein the first total synthesis of (±)-trolline, in two steps and 18.0% overall yield.
关键词 total synthesis Trolline ALKALOID
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Signatures of a Universal Spectrum for Nonlinear Variability in Daily Columnar Total Ozone Content 被引量:1
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作者 A. M. Selvam (1) M. Radhamani (1) 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1994年第3期335-342,共8页
Continuous periodogram analyses of sets of 50 to 364 daily mean atmospheric columnar total ozone content at19 globally representative stations indicate that the power spectra fOllow the universal inverse power law for... Continuous periodogram analyses of sets of 50 to 364 daily mean atmospheric columnar total ozone content at19 globally representative stations indicate that the power spectra fOllow the universal inverse power law form of thestatistical normal distribution. The results are consistent with prediction of a cell dynamical system model for atmospheric flows extending up to the stratosphere and above. The unique quantification for nonlinear variability of dailyatmospheric total ozone implies predictability of the total pattern of fluctuations. 展开更多
关键词 OZONE Columnar total ozone
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Continuous flow analysis of dissolved total phosphorus in seawater by UVK_(2)S_(2)O_(8) online digestion method 被引量:1
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作者 YUZhigang RAABEThomas +1 位作者 HEMKENGitta BROCKMANNUwe 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2004年第4期637-645,共9页
Several methods for analysis of dissolved total phosphorus in seawater were reviewed. Discussions were focused on UVirradiation and persulphate oxidation methods which are the most popular dissolved organic phosphorus... Several methods for analysis of dissolved total phosphorus in seawater were reviewed. Discussions were focused on UVirradiation and persulphate oxidation methods which are the most popular dissolved organic phosphorus determinationmethods presently. The compounds used for the phosphorus recovery test were categorized into three groups accordingto their chemical structure. It was found that low power UV irradiation can decompose POC or PC bonds efficientlybut may be inefficient for POP bonds. Heating-bath in acid condition is useful for decomposing POP bonds. Usingthe continuous flow analysis system (Auto-analyzer II), UV digestion and heating-bath, series experiments were carriedout based on the above analysis. Eleven model compounds were employed for the phosphorus recovery test and thefactors influencing the decomposition efficiency of dissolved compounds containing phosphorus were clarified. Finally,the optimal design for determination of dissolved total phosphorus in seawater based on the routine continuous flowanalysis system was presented. For the organic mono-phosphate, the recovery is more than 90% and a recovery of33%~51% was obtained for inorganic or organic polyphosphates. Up to now, this is the highest decompositionefficiency for dissolved phosphorus based on the continuous flow analysis system. 展开更多
关键词 dissolved total phosphorus organic phosphorus ultraviolt persulfate potassium continuous flow analysis
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Chinese expert consensus and practice guideline of totally implantable access port for digestive tract carcinomas 被引量:9
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作者 Ke-Cheng Zhang Lin Chen 《World Journal of Gastroenterology》 SCIE CAS 2020年第25期3517-3527,共11页
Totally implantable access port is a fully implantable drug delivery system that is implanted subcutaneously and can be retained for a long time.Advantages of ports include a simple nursing process,low risk of infecti... Totally implantable access port is a fully implantable drug delivery system that is implanted subcutaneously and can be retained for a long time.Advantages of ports include a simple nursing process,low risk of infection and embolism,and high patient comfort.In order to promote the standardized application of ports in the treatment of digestive tract tumors and reduce port-related complications,the Chinese Research Hospital Association Digestive Tumor Committee,the Chinese Association of Upper Gastrointestinal Surgeons,the Chinese Gastric Cancer Association,and the Gastrointestinal Surgical Group of Chinese Surgical Society Affiliated to Chinese Medical Association have organized multidisciplinary expert discussions at the General Hospital of the People’s Liberation Army and nationwide expert letter reviews and on-site seminars,and formulated an expert consensus of the operation guidelines. 展开更多
关键词 totally implantable access port Digestive tract tumor Consensus and guideline Venous port Peritoneal port Arterial port
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Pollution Tolerance of Smoke in the Distribution of Neurotransmitter Enzyme (Acetylcholine Esterase) and Total Cholesterol in Tissues of Wistar Rats 被引量:1
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作者 A. C. Achudume F. Aina B. Onibere 《Journal of Environmental Protection》 2010年第4期475-479,共5页
This study was designed to assess total animal exposure to non-occupational but environmentally induced smoke through short-term landfill burning toxicity tests at the biochemical levels. Exposure to municipal land-fi... This study was designed to assess total animal exposure to non-occupational but environmentally induced smoke through short-term landfill burning toxicity tests at the biochemical levels. Exposure to municipal land-fill burning using rat model focused primarily on inhalation exposure. The environmental monitoring consisted of 60 days exposure to refuse burning by evaluating the level of protein concentrations, neurotransmitter enzyme acetylcholine esterase (AcHE), and total cholesterol in different tissues of Wistar rats. Protein concentrations tended to decrease in the brain, liver and kidney and slightly increased in the plasma while acetylcholine esterase decreased in brain and liver and increased in the kidney. The non-depletion in total cholesterol levels in the tissues tended to be due to active mobilization towards tissue metabolism. The data were sufficient to support risk assessment for human. 展开更多
关键词 MUNICIPAL Land-Fill SMOKE Pollutants ACETYLCHOline ESTERASE total CHOLESTEROL
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Conceptual design of a Cs2LiLaBr6 scintillator‑based neutron total cross section spectrometer on the back‑n beam line at CSNS 被引量:3
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作者 Da‑Jun Zhao Song Feng +6 位作者 Pin‑Jing Cheng Rong Liu Wen Luo Hao‑Qiang Wang Jie‑Ming Xue Kun Zhu Bo Zheng 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第1期23-32,共10页
To reduce the experimental uncertainty in the 235 U resonance energy region and improve the detection efficiency for neutron total cross section measurements compared with those obtained with the neutron total cross s... To reduce the experimental uncertainty in the 235 U resonance energy region and improve the detection efficiency for neutron total cross section measurements compared with those obtained with the neutron total cross section spectrometer(NTOX), a dedicated lithium-containing scintillation detector has been developed on the Back-n beam line at the China Spallation Neutron Source. The Fast Scintillator-based Neutron Total Cross Section(FAST) spectrometer has been designed based on a Cs2Li La Br6(CLLB) scintillator considering the γ-ray flash and neutron environment on the Back-n beam line. The response of the CLLB scintillator to neutrons and γ-rays was evaluated with different 6Li/7 Li abundance ratios using Geant4. The neutron-γdiscrimination performance of the CLLB has been simulated considering different scintillation parameters, physical designs,and light readout modes. A cubic 6Li-enriched( > 90%) CLLB scintillator, which has a thickness of 4-9 mm and side length of no less than 50 mm to cover the Φ 50 mm neutron beam at the spectrometer position, has been proposed coupling to a side readout SiPM array to construct the FAST spectrometer. The developed simulation techniques for neutron-γ discrimination performance could provide technical support for other neutron-induced reaction measurements on the Back-n beam line. 展开更多
关键词 Neutron total cross section CLLB scintillator GEANT4 Pulse shape discrimination(PSD)
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Research on Total Electric Field for DC Lines Converted from Double-Circuit AC Lines
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作者 Xiaoqian Ma Jiayu Lu +1 位作者 Kun He Wensheng Gao 《Energy and Power Engineering》 2017年第4期598-610,共13页
With rapid growth of power demand, transmission capacity is also in urgent need of upgrading. In some cases, converting existing AC transmission lines to DC lines can Improve the transmission capacity and reduce the c... With rapid growth of power demand, transmission capacity is also in urgent need of upgrading. In some cases, converting existing AC transmission lines to DC lines can Improve the transmission capacity and reduce the construction investment. In this paper, the upstream finite element method was expanded to calculate the total electric field of same tower multi-circuit DC lines converted from double-circuit AC lines, and the validity of the algorithm was confirmed by experiments. Taking a DC line converted from a typical same tower 500 kV double-circuit AC transmission line as an example, the surface electric field and the ground total electric field in different pole conductor arrangement schemes were calculated and analyzed, and the critical height of pole conductors for DC lines in residential and non-residential area were determined. Then, the corridor width of DC and AC lines at critical height in residential and non-residential areas before and after AC-DC line transformation were compared. The results indicate that for DC lines converted from common 500 kV double-circuit AC lines, the ground total electric field can meet the requirements of corresponding standard with appropriate pole conductor arrangement schemes. 展开更多
关键词 DC lineS Converted from AC lineS Multi-Circuit DC line at SAME Tower Pole Conductor BUNDLES Arrangement Scheme total Electric Field line-to-Ground Distance Corridor Width
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Anatomic Anteversion of the Acetabular Component Correlates with Polyethylene Linear Wear in Total Hip Arthroplasty: The Three-Dimensional Numerical Analysis 被引量:1
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作者 Ima Kosukegawa Satoshi Nagoya +4 位作者 Mitsunori Kaya Mikito Sasaki Shunichiro Okazaki Daisuke Suzuki Toshihiko Yamashita 《Open Journal of Orthopedics》 2016年第6期126-134,共9页
Background: Although abduction of the acetabular component is considered to predict factors for polyethylene wear attributable to osteolysis, other radiographic factors have yet to be elucidated. The purpose of the pr... Background: Although abduction of the acetabular component is considered to predict factors for polyethylene wear attributable to osteolysis, other radiographic factors have yet to be elucidated. The purpose of the present study was to evaluate whether anteversion or change in implantation angle of the acetabular component influences polyethylene linear wear by using standing and supine radiographs of the hip joint. Methods: Standing and supine plain anteroposterior radiographs of 62 hip joints in which cementless total hip arthroplasty was performed were examined for polyethylene linear wear rate (mm/year), pelvic inclination, and radiological inclination and anatomic anteversion of the acetabular component. Results: All correlation coefficients of measurements of polyethylene linear wear, pelvic inclination angle, anatomical anteversion angle and radiological inclination angle were calculated highly. And by the three-dimensional numerical analysis, anatomic anteversion of the acetabular component had at least some effect on the degree of polyethylene wear. Conclusion: This study suggests that increased anteversion of the acetabular component reduces polyethylene linear wear in metal-on-polyethylene total hiparthroplasty. 展开更多
关键词 total Hiparthroplasty Polyethylene linear Wear Standing Position Settingangle of Acetabular Component
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Nonlinear total least-squares variance component estimation for GM(1,1)model 被引量:2
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作者 Leyang Wang Jianqiang Sun Qiwen Wu 《Geodesy and Geodynamics》 CSCD 2021年第3期211-217,共7页
The solution of the grey model(GM(1,1)model)generally involves equal-precision observations,and the(co)variance matrix is established from the prior information.However,the data are generally available with unequal-pr... The solution of the grey model(GM(1,1)model)generally involves equal-precision observations,and the(co)variance matrix is established from the prior information.However,the data are generally available with unequal-precision measurements in reality.To deal with the errors of all observations for GM(1,1)model with errors-in-variables(EIV)structure,we exploit the total least-squares(TLS)algorithm to estimate the parameters of GM(1,1)model in this paper.Ignoring that the effect of the improper prior stochastic model and the homologous observations may degrade the accuracy of parameter estimation,we further present a nonlinear total least-squares variance component estimation approach for GM(1,1)model,which resorts to the minimum norm quadratic unbiased estimation(MINQUE).The practical and simulative experiments indicate that the presented approach has significant merits in improving the predictive accuracy in comparison with control methods. 展开更多
关键词 GM(1 1)model Minimum norm quadratic unbiased estimation(MINQUE) total least-squares(TLS) Unequal-precision measurement Variance component estimation(VCE)
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Influence of the total gas flow rate on high rate growth microcrystalline silicon films and solar cells
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作者 韩晓艳 侯国付 +8 位作者 张晓丹 魏长春 李贵君 张德坤 陈新亮 孙健 张建军 赵颖 耿新华 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第8期3563-3567,共5页
This paper reports that high-rate-deposition of microcrystalline silicon solar cells was performed by very-highfrequency plasma-enhanced chemical vapor deposition. These solar cells, whose intrinsic μc-Si:H layers w... This paper reports that high-rate-deposition of microcrystalline silicon solar cells was performed by very-highfrequency plasma-enhanced chemical vapor deposition. These solar cells, whose intrinsic μc-Si:H layers were prepared by using a different total gas flow rate (Ftotal), behave much differently in performance, although their intrinsic layers have similar crystalline volume fraction, opto-electronic properties and a deposition rate of - 1.0 nm/s. The influence of Ftotal on the micro-structural properties was analyzed by Raman and Fourier transformed infrared measurements. The results showed that the vertical uniformity and the compact degree of μc-Si:H thin films were improved with increasing Ftotal. The variation of the microstructure was regarded as the main reason for the difference of the J V parameters. Combined with optical emission spectroscopy, we found that the gas temperature plays an important role in determining the microstructure of thin films. With Ftotal of 300 sccm, a conversion efficiency of 8.11% has been obtained for the intrinsic layer deposited at 8.5 A/s (1 A=0.1 nm). 展开更多
关键词 microcrystalline silicon high rate solar cell total gas flow rate
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“Meniscal” scar as a landmark for the joint line in revision total knee replacement
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作者 Wasim Sardar Khan Jagmeet Bhamra +1 位作者 Rhodri Williams Rhidian Morgan-Jones 《World Journal of Orthopedics》 2017年第1期57-61,共5页
AIM To determine whether tissue identified at the joint line was actually remnant "meniscal" scar tissue or not. METHODS Nine patients undergoing revision knee surgery following informed consent had meniscal... AIM To determine whether tissue identified at the joint line was actually remnant "meniscal" scar tissue or not. METHODS Nine patients undergoing revision knee surgery following informed consent had meniscal scar tissue sent to the histology department for analyses. All revisions were performed where joint line had been raised or lowered at earlier surgery. Although preoperative radiographic evaluations suggested that the joint line had been altered, intraoperatively there was scar tissue at the level of the recreated joint line. This scar tissue has traditionally been described as meniscal scar, and to identify the origins of this tissue, samples were sent for histological analyses. The tissue samples were stored in formalin, and embedded and sectioned before undergoing histochemical staining. All samples underwent macroscopic and microscopic examination by a histopathologist who was blind to the study aims. The specific features that were examined included tissue organisation, surface and central composition, cellular distribution including histiocytes, nuclear ratio and vasculature. Atypical and malignant features, inflammation and degeneration were specifically looked for. A statistical review of the study was performed by a biomedical statistician.RESULTS The histological findings for the nine patients showingthe macroscopic and microscopic findings, and the conclusion are outlined in a Table. The histological analyses were reviewed to determine whether the tissue samples were likely to be meniscal scar tissue. The response was yes(2, 22%), no(6, 67%) and maybe(1,11%) based on the conclusions. The results were "yes"when on macroscopy, firm cream tissue was identified.In these two "yes" samples, microscopic analyses showed organised fibrous tissue with focal degenerative areas with laminated pattern associated with histiocytes peripherally but no inflammation. The "no" samples were assessed macroscopically and microscopically and were deemed to have appearances representing fibrous synovial tissue and features in keeping with degenerate scar tissue or connective tissue. One sample was indeterminate and microscopically contained fibrocollagenous tissue with synovial hyperplasia. It also contained some degenerate hyalinised tissue that may represent cartilage, but the appearances were not specific. CONCLUSION Based on our pilot study, we recommend reliance on a number of markers to identify the joint line as outlined above, and to exercise caution in using the "meniscal"scar. 展开更多
关键词 Menical SCAR Joint line REVISION surgery KNEE HISTOLOGY
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