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Endoscopic radial incision and cutting method for adult congenital duodenal webs:A case report
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作者 Hyun Deok Shin 《World Journal of Clinical Cases》 SCIE 2024年第18期3622-3628,共7页
BACKGROUND Congenital duodenal webs are rare in adults and can lead to various symptoms such as nausea,vomiting,and postprandial fullness.The treatment for this disease is mostly surgical.Endoscopic treatment techniqu... BACKGROUND Congenital duodenal webs are rare in adults and can lead to various symptoms such as nausea,vomiting,and postprandial fullness.The treatment for this disease is mostly surgical.Endoscopic treatment techniques have been developed and attempted for this disease.Endoscopic radial incision and cutting(RIC)techniques are reportedly very effective in benign anastomotic stricture.This case report highlights the effectiveness and safety of endoscopic RIC as a minimally invasive treatment for adult congenital duodenal webs.CASE SUMMARY A 23-year-old female patient with indigestion was referred to a tertiary hospital.The patient complained of postprandial fullness in the epigastric region.Previous physical examinations or blood tests indicated no abnormalities.Computed tomography revealed an eccentric broad-based delayed-enhancing mass-like lesion in the second portion of the duodenum.Endoscopy showed an enlarged gastric cavity and a significantly dilated duodenal bulb;a very small hole was observed in the distal part of the second portion,and scope passage was not possible.Gastrografin upper gastrointestinal series was performed,revealing an intraduodenal barium contrast-filled sac with a curvilinear narrow radiolucent rim,a typical"windsock"sign.Endoscopic RIC was performed on the duodenal web.The patient recovered uneventfully.Follow-up endoscopy showed a patent duodenal lumen without any residual stenosis.The patient reported complete resolution of symptoms at the 18-month follow-up.CONCLUSION Endoscopic RIC may be an effective treatment for congenital duodenal webs in adults. 展开更多
关键词 Congenital duodenal web Endoscopic treatment Radial incision and cutting method Surgery Case report
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Bamboo (Bambusa vulgaris) Regeneration by Cuttings: Comparative Study of Planting Methods of Culm Cuttings at UR-CAVM Busogo Campus Tree Nursery
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作者 Jean Nduwamungu 《Journal of Health Science》 2018年第1期42-48,共7页
Bamboo is one of the fastest growing and highest yielding renewable resources with multiple uses in the world. Lack of seedlings in sufficient number has generally been a major constraint in establishing more bamboo p... Bamboo is one of the fastest growing and highest yielding renewable resources with multiple uses in the world. Lack of seedlings in sufficient number has generally been a major constraint in establishing more bamboo plantations. This study investigated the efficiency of regenerating Bambusa vulgaris through cuttings at Busogo sector, Musanze district, using vertical and horizontal methods with and without water treatment. The experiment consisted in a RCBD (Randomized Complete Block Design) with 4 replications. The growth and sprouting of the 64 cuttings were monitored for three months and 18 days (105 days). In terms of planting method, horizontal planting method showed best sprouting percentage of 68%. In terms of treatment used, horizontal planting method without using water treatment showed slightly better sprouting percentage of 60%. The results further show that about 87% of sprouts had between 0 and 30 cm height and 98% of sprouts had basal diameter ranging from 0 to 20 mm only 105 days after planting. Indeed, the horizontal planting methods provided highest survival rate of sprouts than the vertical planting method (74%) of planted cuttings. Furthermore, the results show that, 105 days after planting, cuttings with horizontal method were more productive in terms of root development. In terms of planting method using water treatment, the horizontal planting method with water treatment showed highest rooting percentage (44%). Therefore, farmers should be trained and encouraged to use horizontal planting method using water treatment in order to get better results in regenerating bamboo through cuttings. 展开更多
关键词 BAMBOO bamboo regeneration culm cuttings cuttings planting methods.
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Power Generation Expansion Planning Using an Interior Point with Cutting Plane (IP/CP) Method
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作者 Moon, Guk-Hyun Seo, In-Yong Jaehee, Lee 《Journal of Mechanics Engineering and Automation》 2015年第11期640-645,共6页
The generation expansion planning is one of complex mixed-integer optimization problems, which involves a large number of continuous or discrete decision variables and constraints. In this paper, an interior point wit... The generation expansion planning is one of complex mixed-integer optimization problems, which involves a large number of continuous or discrete decision variables and constraints. In this paper, an interior point with cutting plane (IP/CP) method is proposed to solve the mixed-integer optimization problem of the electrical power generation expansion planning. The IP/CP method could improve the overall efficiency of the solution and reduce the computational time. Proposed method is combined with the Bender's decomposition technique in order to decompose the generation expansion problem into a master investment problem and a slave operational problem. The numerical example is presented to compare with the effectiveness of the proposed algorithm. 展开更多
关键词 Benders' decomposition technique power generation expansion planning interior point with cutting plane method mixed integer programming.
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An Improved Method of Extracting Artemisia abrotanum Genomic DNA 被引量:14
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作者 石开明 周毅峰 《Agricultural Science & Technology》 CAS 2008年第2期36-38,共3页
[ Objective ] The objective of this study is to explore a rapid and efficient method of extracting genomic DNA from Artemisia abrotanum. [ Method] Three methods of Cutting Method, Liquid Nitrogen Method and Quartz San... [ Objective ] The objective of this study is to explore a rapid and efficient method of extracting genomic DNA from Artemisia abrotanum. [ Method] Three methods of Cutting Method, Liquid Nitrogen Method and Quartz Sand Method based on SDS method were employed to extract Artemisia abrotanum genomlc DNA from tender leaf at seedling stage, tender spike and old leaf at heading stage. The obtained DNAs were detected by absorbance detection, agarose gel and PCR amplification. [ Result ] Cutting Method performed better than the other two methods compared in purity, extracting cycle and cost, accordingly more suitable for PCR amplification. The results also show that young spike is the best material for extracting genomic DNA from Artemisia Annua. 展开更多
关键词 Artemisia abrotanum DNA extraction cutting method
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Focal Mechanism Solution of the February 23,2014,M_L3.8 Rongchang Earthquake with the CAP(Cut and Paste)Method 被引量:1
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作者 Wang Xiaolong Lei Xinglin +3 位作者 Guo Xing Yu Tianhang Gou Xianbin Yu Gouzheng 《Earthquake Research in China》 CSCD 2016年第2期233-239,共7页
A M_L3.8 earthquake occurred on February 23,2014 in Rongchang County,which is located at the southern edge of the Sichuan Basin in the border area between Sichuan and Chongqing. This paper presents results of focal me... A M_L3.8 earthquake occurred on February 23,2014 in Rongchang County,which is located at the southern edge of the Sichuan Basin in the border area between Sichuan and Chongqing. This paper presents results of focal mechanism solution of this earthquake using the CAP( cut and paste) method based on broadband seismograms recorded by regional seismic stations. Our results show that the moment magnitude is M_W3. 09 and focal depth is 3km. The hypocenter of this earthquake is located close to a buried fault in the Luoguangshan anticline. Oil prospecting and deep drilling data indicate that this buried fault is a thrust fault,striking SW230°,dipping NW45°,and 1. 7km deep. There are some injection wells within the anticline,and significant injection-induced earthquakes were observed during the periods of injection of waste water into the deep formations through those wells. The best double couple solution of the M_L3.8 earthquake is 247°,48°and 104° for strike,dip and rate,respectively,for one nodal plane( and 46°,44° and 74°for another nodal plane),which is in agreement with the geometry of the buried fault.Therefore,we conclude that the M_L3.8 Rongchang earthquake is possibly the result of faulting along the buried reverse fault induced by water injection under the compressive stress regime in the area. 展开更多
关键词 Rongchang earthquake Cut and Paste method Focal mechanismInjection-induced earthquake
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Focal Mechanism Solution of the 2011 M_S4.8 Anqing Earthquake Determined from the CAP Method
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作者 Hong Dequan Wang Xingzhou +2 位作者 Han Libo Qi Hao Zhang Bing 《Earthquake Research in China》 2012年第2期268-276,共9页
In this article, we have inverted local broadband waveform data to determine the focal mechanism of the 2011 Ms4.8 Anqing earthquake. Our results show that the best double couple solution of the Ms4.8 event is 16°... In this article, we have inverted local broadband waveform data to determine the focal mechanism of the 2011 Ms4.8 Anqing earthquake. Our results show that the best double couple solution of the Ms4.8 event is 16°, 74° and 120° for strike, dip and rake angles of one nodal plane respectively, and 131 °, 33°, 30° for the other nodal plane. The estimated focal depth is about 3kin. Both strikes of the two nodal planes differ significantly to the strike of Susong-Zongyang fault, along which seismic activity has been at a low level since the Late Quaternary. This implies that this earthquake may not have occurred on the Susong-Zongyang fault, and we infer that a buried fault with strike of NNE may be the seismogenic structure of this event. 展开更多
关键词 Anqing earthquake Cut And Paste method Focal mechanism solution
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From the new Austrian tunneling method to the geoengineering condition evaluation and dynamic controlling method 被引量:1
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作者 Yanjun Shang Kun Li +1 位作者 Wantong He Chunbo Sheng 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2014年第4期366-372,共7页
The new Austrian tunneling method (NATM) is widely applied in design and construction of underground engineering projects. When the type and distribution of unfavorable geological bodies (UGBs) associated with the... The new Austrian tunneling method (NATM) is widely applied in design and construction of underground engineering projects. When the type and distribution of unfavorable geological bodies (UGBs) associated with their influences on geoengineering are complicated or unfortunately are overlooked, we should pay more attentions to internal features of rocks grades IV and V (even in local but mostly controlling zones). With increasing attentions to the characteristics, mechanism and influences of engineering construction-triggered geohazards, it is crucial to fully understand the disturbance of these geohazards on project construction. A reasonable determination method in construction procedure, i.e. the shape of working face, the type of engineering support and the choice of feasible procedure, should be considered in order to mitigate the construction-triggered geohazards. Due to their high sensitivity to groundwater and in-situ stress, various UGBs exhibit hysteretic nature and failure modes. To give a complete understanding on the internal causes, the emphasis on advanced comprehensive geological forecasting and overall reinforcement treatment is therefore of more practical significance. Compre- hensive evaluation of influential factors, identification of UGB, and measures of discontinuity dynamic controlling comprises the geoengineering condition evaluation and dynamic controlling method. In a case of a cut slope, the variations of UGBs and the impacts of key environmental factors are presented, where more severe construction-triggered geohazards emerged in construction stage than those predicted in design and field investigation stages. As a result, the weight ratios of different influential factors with respect to field investigation, design and construction are obtained. 展开更多
关键词 Unfavorable geological body (UGB)Multi-factor interaction matrix Discontinuity dynamic controlling (DDC)Cut slope Geoengineering condition evaluation and dynamic controlling (GEDC) method
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Enhanced Feature Fusion Segmentation for Tumor Detection Using Intelligent Techniques
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作者 R.Radha R.Gopalakrishnan 《Intelligent Automation & Soft Computing》 SCIE 2023年第3期3113-3127,共15页
In thefield of diagnosis of medical images the challenge lies in tracking and identifying the defective cells and the extent of the defective region within the complex structure of a brain cavity.Locating the defective... In thefield of diagnosis of medical images the challenge lies in tracking and identifying the defective cells and the extent of the defective region within the complex structure of a brain cavity.Locating the defective cells precisely during the diagnosis phase helps tofight the greatest exterminator of mankind.Early detec-tion of these defective cells requires an accurate computer-aided diagnostic system(CAD)that supports early treatment and promotes survival rates of patients.An ear-lier version of CAD systems relies greatly on the expertise of radiologist and it con-sumed more time to identify the defective region.The manuscript takes the efficacy of coalescing features like intensity,shape,and texture of the magnetic resonance image(MRI).In the Enhanced Feature Fusion Segmentation based classification method(EEFS)the image is enhanced and segmented to extract the prominent fea-tures.To bring out the desired effect the EEFS method uses Enhanced Local Binary Pattern(EnLBP),Partisan Gray Level Co-occurrence Matrix Histogram of Oriented Gradients(PGLCMHOG),and iGrab cut method to segment image.These prominent features along with deep features are coalesced to provide a single-dimensional fea-ture vector that is effectively used for prediction.The coalesced vector is used with the existing classifiers to compare the results of these classifiers with that of the gen-erated vector.The generated vector provides promising results with commendably less computatio nal time for pre-processing and classification of MR medical images. 展开更多
关键词 Enhanced local binary pattern LEVEL iGrab cut method magnetic resonance image computer aided diagnostic system enhanced feature fusion segmentation enhanced local binary pattern
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Risk factors for bleeding after endoscopic mucosal resection 被引量:25
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作者 Masatsugu Shiba Kazuhide Higuchi +12 位作者 Kaori Kadouchi Ai Montani Kazuki Yamamori Hirotoshi Okazaki Makiko Taguchi Tomoko Wada Atsushi Itani Toshio Watanabe Kazunari Tominaga Yoshihiro Fujiwara Tomoshige Hayashi Kei Tsumura Tetsuo Arakawa 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第46期7335-7339,共5页
AIM: To clarify the risk factors for bleeding after endoscopic mucosal resection (EMR). METHODS: A total of 297 consecutive patients who underwent EMR were enrolled. Some of the patients had multiple lesions. Blee... AIM: To clarify the risk factors for bleeding after endoscopic mucosal resection (EMR). METHODS: A total of 297 consecutive patients who underwent EMR were enrolled. Some of the patients had multiple lesions. Bleeding requiring endoscopic treatment was defined as bleeding after EMR. Odds ratios (OR) with 95% confidence intervals (CI), calculated by logistic regression with multivariate adjustments for covariates, were the measures of association. RESULTS: Of the 297 patients, 57 (19.2%) patients with bleeding after EMR were confirmed. With multivariate adjustment, the cutting method of EMR, diameter, and endoscopic pattern of the tumor were associated with the risk of bleeding after EMR. The multivariate-adjusted OR for bleeding after EMR using endoscopic aspiration mucosectomy was 3.07 (95%CI, 1.59-5.92) compared with strip biopsy. The multiple-adjusted OR for bleeding after EMR for the highest quartile (16-50 mm) of tumor diameter was 5.63 (95%CI, 1.84-17.23) compared with that for the lowest (4-7 mm). The multiple-adjusted OR for bleeding after EMR for depressed type of tumor was 4.21 (95%CI, 1.75-10.10) compared with elevated type. CONCLUSION: It is important to take tumor charactedstics (tumor size and endoscopic pattern) and cutting method of EMR into consideration in predicting bleeding after EMR. 展开更多
关键词 Endoscopic mucosal resection BLEEDING Tumor characteristics cutting method
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Analysis of factors and countermeasures of mining subsidence in Kaiyang Phosphorus Mine 被引量:11
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作者 邓建 边利 +2 位作者 李夕兵 赵国彦 王新民 《Journal of Central South University of Technology》 EI 2006年第6期733-737,共5页
Ground crack and subsidence were investigated in Kaiyang Phosphorus Mine as an example. Contribution factors to cause ground crack and mining subsidence were studied, including mining method, mining depth and ore thic... Ground crack and subsidence were investigated in Kaiyang Phosphorus Mine as an example. Contribution factors to cause ground crack and mining subsidence were studied, including mining method, mining depth and ore thickness and stope size, dip angle of orebody, geological structure, nature of overburden and water contents, and roof supports, etc. Countermeasures against cracks and subsidence were put forward. The uniaxial compressive strength of compounded phosphorus gypsum after 28 d of curing period was tested to be more than 1 MPa. Phosphorus gypsum can be used as materials for the backfill of stope. By comparison and numerical simulation, cut and fill mining method with middle-deep drilling holes and ore transportation by blasting force was selected as the optimum mining method in Kaiyang Phosphorus Mine. 展开更多
关键词 mining subsidence ground crack cut and fill mining method Kaiyang Phosphorus Mine
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Investigation and characterization of mining subsidence in Kaiyang Phosphorus Mine 被引量:8
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作者 邓建 边利 《Journal of Central South University of Technology》 EI 2007年第3期413-417,共5页
In Kaiyang Phosphorus Mine, serious environmental and safety problems are caused by large scale mining activities in the past 40 years. These problems include mining subsidence, low recovery ratio, too much dead ore i... In Kaiyang Phosphorus Mine, serious environmental and safety problems are caused by large scale mining activities in the past 40 years. These problems include mining subsidence, low recovery ratio, too much dead ore in pillars, and pollution of phosphorus gypsum. Mining subsidence falls into four categories: curved ground and mesa, ground cracks and collapse hole, spalling and eboulement, slope slide and creeping. Measures to treat the mining subsidence were put forward: finding out and managing abandoned stopes, optimizing mining method (cut and fill mining method), selecting proper backfilling materials (phosphogypsum mixtures), avoiding disorder mining operation, and treating highway slopes. These investigations and engineering treatment methods are believed to be able to contribute to the safety extraction of ore and sustainable development in Kaiyang Phosphorus Mine. 展开更多
关键词 mining subsidence ground cracking safety Kaiyang Phosphorus Mine cut and fill mining method
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Rock excavation using surface miners: An overview of some design and operational aspects 被引量:1
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作者 Prakash Amar Murthy Vemavarapu Mallika Sita Ramachandra Singh Kalendra Bahadur 《International Journal of Mining Science and Technology》 SCIE EI 2013年第1期33-40,共8页
Surface miner, a continuous mining machine, is being manufactured in India and abroad owing to enhanced demand of production in various mining industries like coal, limestone, gypsum, bauxite etc. Different types of s... Surface miner, a continuous mining machine, is being manufactured in India and abroad owing to enhanced demand of production in various mining industries like coal, limestone, gypsum, bauxite etc. Different types of surface miners are manufactured today based on cutting drum placement and design specifications. Selective mining without drilling and blasting, high production and small size products are some of the prominent attractive features obtained with these moving marvels. This machine can be used with good efficiency in soft to medium hard rock (100-120 MPa). This paper synthesizes the different applications, equipment models, features offered, operating methods, cutting performance assessment models as well as typical production performance of surface miner in coal and limestone mines of India. Engine hour metre reading, diesel and pick consumptions are linearly influenced by production. The emphasis for future research is also brought out. 展开更多
关键词 Surface miner cutting performance Compressive strength Operating methods
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Mini-batch cutting plane method for regularized risk minimization
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作者 Meng-long LU Lin-bo QIAO +2 位作者 Da-wei FENG Dong-sheng LI Xi-cheng LU 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2019年第11期1551-1563,共13页
Although concern has been recently expressed with regard to the solution to the non-convex problem, convex optimization is still important in machine learning, especially when the situation requires an interpretable m... Although concern has been recently expressed with regard to the solution to the non-convex problem, convex optimization is still important in machine learning, especially when the situation requires an interpretable model. Solution to the convex problem is a global minimum, and the final model can be explained mathematically. Typically, the convex problem is re-casted as a regularized risk minimization problem to prevent overfitting. The cutting plane method (CPM) is one of the best solvers for the convex problem, irrespective of whether the objective function is differentiable or not. However, CPM and its variants fail to adequately address large-scale data-intensive cases because these algorithms access the entire dataset in each iteration, which substantially increases the computational burden and memory cost. To alleviate this problem, we propose a novel algorithm named the mini-batch cutting plane method (MBCPM), which iterates with estimated cutting planes calculated on a small batch of sampled data and is capable of handling large-scale problems. Furthermore, the proposed MBCPM adopts a "sink" operation that detects and adjusts noisy estimations to guarantee convergence. Numerical experiments on extensive real-world datasets demonstrate the effectiveness of MBCPM, which is superior to the bundle methods for regularized risk minimization as well as popular stochastic gradient descent methods in terms of convergence speed. 展开更多
关键词 Machine learning Optimization methods Gradient methods cutting plane method
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A Cutting Hyperplane Projection Method for Solving Generalized Quasi-Variational Inequalities
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作者 Ming-Lu Ye 《Journal of the Operations Research Society of China》 EI CSCD 2016年第4期483-501,共19页
The generalized quasi-variational inequality is a generalization of the generalized variational inequality and the quasi-variational inequality.The study for the generalized quasi-variational inequality is mainly conc... The generalized quasi-variational inequality is a generalization of the generalized variational inequality and the quasi-variational inequality.The study for the generalized quasi-variational inequality is mainly concerned with the solution existence theory.In this paper,we present a cutting hyperplane projection method for solving generalized quasi-variational inequalities.Our method is neweven if it reduces to solve the generalized variational inequalities.The global convergence is proved under certain assumptions.Numerical experiments have shown that our method has less total number of iterative steps than the most recent projection-like methods of Zhang et al.(Comput Optim Appl 45:89–109,2010)for solving quasi-variational inequality problems and outperforms the method of Li and He(J Comput Appl Math 228:212–218,2009)for solving generalized variational inequality problems. 展开更多
关键词 Generalized quasi-variational inequality cutting hyperplane projection method Point-to-set mapping PSEUDOMONOTONE
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The First Eccentric Zagreb Index of Linear Polycene Parallelogram of Benzenoid
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作者 Mehdi Alaeiyan Mohammad Reza Farahani +1 位作者 Muhammad Kamran Jamil M. R. Rajesh Kanna 《Open Journal of Applied Sciences》 2016年第5期315-318,共4页
Let G = (V,E) be a graph, where V(G) is a non-empty set of vertices and E(G) is a set of edges, e = uv∈E(G), d(u) is degree of vertex u. Then the first Zagreb polynomial and the first Zagreb index Zg<sub>1</... Let G = (V,E) be a graph, where V(G) is a non-empty set of vertices and E(G) is a set of edges, e = uv∈E(G), d(u) is degree of vertex u. Then the first Zagreb polynomial and the first Zagreb index Zg<sub>1</sub>(G,x) and Zg<sub>1</sub>(G) of the graph G are defined as Σ<sub>uv∈E(G)</sub>x<sup>(d<sub>u</sub>+d<sub>v</sub>)</sup> and Σ<sub>e=uv∈E(G)</sub>(d<sub>u</sub>+d<sub>v</sub>) respectively. Recently Ghorbani and Hosseinzadeh introduced the first Eccentric Zagreb index as Zg<sub>1</sub>*</sup>=Σ<sub>uv∈E(G)</sub>(ecc(v)+ecc(u)), that ecc(u) is the largest distance between u and any other vertex v of G. In this paper, we compute this new index (the first Eccentric Zagreb index or third Zagreb index) of an infinite family of linear Polycene parallelogram of benzenoid. 展开更多
关键词 Molecular Graph Linear Polycene Parallelogram of Benzenoid Zagreb Topological Index Eccentricity Connectivity Index Cut method
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Source Mechanism of the M_S 6.6 Xinyuan-Hejing Earthquake of June 30,2012
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作者 Ran Huimin Zhang Zhibin Zhao Qing 《Earthquake Research in China》 CSCD 2015年第2期247-257,共11页
In this article,we use the CAP method to invert the focal mechanism of Xinyuan-Hejing M S6. 6 earthquake on June 30,2012. Our result shows that the best double couple solution of the M S6. 6 event is 299°,68°... In this article,we use the CAP method to invert the focal mechanism of Xinyuan-Hejing M S6. 6 earthquake on June 30,2012. Our result shows that the best double couple solution of the M S6. 6 event is 299°,68° and 164° for strike,dip and rake angles respectively. The other nodal plane is 35°,75° and 23°. The azimuth and dip angle of the P-axis are 166°and 5°,those of the T-axis are 258° and 26°. The moment magnitude is 6. 3. The estimated focal depth is about 21 km. The predominant rupture direction of this seismic sequence is NWW. The dip angles are between 60° and 90°. The rake angles are in the majority of ± 180°± 30°. The predominant strike of the azimuthal angle of the P-axis is near NS and T-axis is near EW. Preliminary analysis indicates that nodal plane I is the seismogenic fault,which is a NWW-trending,nearly upright left-lateral strike-slip fault.The displacement property,the principal compressive stress of this M S6. 6 earthquake and the P-axis preponderant orientation of this seismic sequence agree with the characteristics of the tectonic stress field of the focal area and its surroundings. 展开更多
关键词 The Xinyuan-Hejing earthquake Cut and paste (CAP) method Sourcemechanim
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Enhancing cut selection through reinforcement learning 被引量:1
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作者 Shengchao Wang Liang Chen +1 位作者 Lingfeng Niu Yu-Hong Dai 《Science China Mathematics》 SCIE CSCD 2024年第6期1377-1394,共18页
With the rapid development of artificial intelligence in recent years,applying various learning techniques to solve mixed-integer linear programming(MILP)problems has emerged as a burgeoning research domain.Apart from... With the rapid development of artificial intelligence in recent years,applying various learning techniques to solve mixed-integer linear programming(MILP)problems has emerged as a burgeoning research domain.Apart from constructing end-to-end models directly,integrating learning approaches with some modules in the traditional methods for solving MILPs is also a promising direction.The cutting plane method is one of the fundamental algorithms used in modern MILP solvers,and the selection of appropriate cuts from the candidate cuts subset is crucial for enhancing efficiency.Due to the reliance on expert knowledge and problem-specific heuristics,classical cut selection methods are not always transferable and often limit the scalability and generalizability of the cutting plane method.To provide a more efficient and generalizable strategy,we propose a reinforcement learning(RL)framework to enhance cut selection in the solving process of MILPs.Firstly,we design feature vectors to incorporate the inherent properties of MILP and computational information from the solver and represent MILP instances as bipartite graphs.Secondly,we choose the weighted metrics to approximate the proximity of feasible solutions to the convex hull and utilize the learning method to determine the weights assigned to each metric.Thirdly,a graph convolutional neural network is adopted with a self-attention mechanism to predict the value of weighting factors.Finally,we transform the cut selection process into a Markov decision process and utilize RL method to train the model.Extensive experiments are conducted based on a leading open-source MILP solver SCIP.Results on both general and specific datasets validate the effectiveness and efficiency of our proposed approach. 展开更多
关键词 reinforcement learning mixed-integer linear programming cutting plane method cut selection
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Novel pipe-roof method for a super shallow buried and large-span metro underground station 被引量:3
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作者 Bo Lu Jiachao Dong +6 位作者 Wen Zhao Xi Du Cheng Cheng Qian Bai Zhiguo Wang Mingcheng Zhao Jianyong Han 《Underground Space》 SCIE EI 2022年第1期134-150,共17页
To address the inadequacies of traditional pipe-roof methods,the steel support cutting pipe method(SSCP)—a novel pipe-roof method that improves construction security and underground space usage—is proposed.To furthe... To address the inadequacies of traditional pipe-roof methods,the steel support cutting pipe method(SSCP)—a novel pipe-roof method that improves construction security and underground space usage—is proposed.To further explore the applications of SSCP,its design scheme ought to be optimized.The failure mode and mechanical behaviors of the SSCP were investigated through laboratory experiments.Subsequently,a series of finite element models(FEMs)was established to study the deformation characteristics.Further,the parameters of the steel support of the proposed structure were optimized using fuzzy mathematics.The results indicated the ultimate bearing capacity to be 366.8 kN,and the specimen began to yield when the external load reached 70%of the ultimate value.The lon-gitudinal spacing of the steel supports,transverse steel support size,and vertical steel support size had significant effect on the vertical deformation of the steel support and the ground settlement.Finally,the optimal combination of steel supports for the SSCP structure was obtained. 展开更多
关键词 Steel support cutting pipe method Ground settlement Deformation characteristics Fuzzy mathematical theory Parameter optimization
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Carbon isotope fractionation during CH_4 transport in paddy fields 被引量:1
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作者 ZHANG GuangBin JI Yang +2 位作者 LIU Gang MA Jing XU Hua 《Science China Earth Sciences》 SCIE EI CAS 2014年第7期1664-1670,共7页
In this study,to further promote the application of the stable carbon isotope natural abundance(SCINA)method to the study of CH4in paddy fields in China,field experiments were carried out to investigate carbon isotope... In this study,to further promote the application of the stable carbon isotope natural abundance(SCINA)method to the study of CH4in paddy fields in China,field experiments were carried out to investigate carbon isotope fractionation during CH4transport in both rice-and non-rice-growing seasons.More importantly,two new methods for the measurement of the CH4transport fractionation factor(εtransport)in paddy fields were introduced.The results indicated that the closed chamber+syringe method was much better for the determination ofεtransport during the non-rice-growing season.Presently,εtransport was calculated using theδ13C value of the CH4emitted from a rice field minus that of the CH4in the floodwater(–6.7‰to–3.0‰).In addition,there were three methods available for estimatingεtransport during the rice-growing season:deduction of theδ13C value of the CH4in the floodwater from that of the CH4emitted from the field(–16.6‰to–15.2‰);deduction of theδ13C value of the CH4in the soil pore water from that of the CH4emitted from the field(–13.2‰to–1.1‰);and deduction of theδ13C value of the CH4in the aerenchyma of plants from that of the CH4emitted from plants(–16.3‰to–10.9‰).Unfortunately,the first two methods showed relatively large uncertainties.Only the last one,the dividing+cutting method,was not only scientific and reliable but also provided accurate measurements. 展开更多
关键词 paddy field CH4 transport isotope fractionation factor closed chamber syringe method dividing cutting method
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The Entrance Effect on Gases Flow Characteristics in Micro-tube 被引量:1
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作者 Chengwen Li Li Jia Tiantian Zhang 《Journal of Thermal Science》 SCIE EI CAS CSCD 2009年第4期353-357,共5页
Entrance region may have important effect on gases flow characteristics in micro-channels. It's concluded in the available papers that the entrance effect causes significant difference. An experimental system of s... Entrance region may have important effect on gases flow characteristics in micro-channels. It's concluded in the available papers that the entrance effect causes significant difference. An experimental system of single-phase gas flow characteristics in microchannels was set up. Flow characteristics of nitrogen in PEEK polymer micro-tube (hydraulic diameter is 553btm) was studied experimentally. According to the data of nitrogen flow in the micro-tube with the length ranging from 0. 1m to1.524m, it is shown that the friction constant becomes higher when the tube becomes shorter. By using pipe cutting methods, it's confirmed that entrance effect is one of the key factors that cause friction constant higher than conventional theory. It's found that friction constant of fully developed flow is lower than the value predicted by conventional theory in turbulent region. The result indicates that the flow transition occurs at Reynolds number ranging from 1600-2000. The phenomenon of obvious early transition is not found. 展开更多
关键词 MICROCHANNEL the length of entrance region entrance effect constant friction method of cutting tube
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