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Detailed seismic zoning of the East Kazakhstan region in the Republic of Kazakhstan
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作者 Natalya V.Silacheva N.P.Stepanenko +2 位作者 O.K.Kurilova A.D.Kudabayeva A.T.Danabayeva 《Geodesy and Geodynamics》 EI CSCD 2024年第2期156-165,共10页
Kazakhstan is currently drafting new construction regulations that comply with the major provisions of the Eurocodes.Such regulations are created on the basis of seismic zoning maps of various degrees of detail,develo... Kazakhstan is currently drafting new construction regulations that comply with the major provisions of the Eurocodes.Such regulations are created on the basis of seismic zoning maps of various degrees of detail,developed by our Institute of Seismology using a new methodological approach for Kazakhstan.The article is about creating the first normative map of the Detailed Seismic Zoning on a probabilistic foundation for the Republic of Kazakhstan’s East Kazakhstan region.We carried out the probabilistic assessment of seismic hazard using a methodology consistent with the main provisions of Eurocode 8and updated compared with that used in developing maps of Kazakhstan’s General Seismic Zoning and seismic microzoning of Almaty.The most thorough and current data accessible for the area under consideration were combined with contemporary analytical techniques.Updates have been done to not only the databases being used but also the way seismic sources were shown,including active faults now.On a scale of 1:1000000,precise seismic zoning maps of the East Kazakhstan region were created for two probabilities of exceedance:10%and 2%in 50 years in terms of peak ground accelerations and macroseismic intensities.The obtained seismic hazard distribution is generally consistent with the General Seismic Zoning of Kazakhstan’s previous findings.However,because active faults were included and a thoroughly revised catalog was used,there are more pronounced zones of increased danger along the fault in the western part of the region.In the west of the territory,acceleration values also increased due to a more accurate consideration of seismotectonic conditions.Zoning maps are the basis for developing new state building regulations of the Republic of Kazakhstan. 展开更多
关键词 Probabilistic seismic hazard assessment detailed seismic zoning Peak ground acceleration Microseismical intensity
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Normalized glandular dose coefficients for digital breast tomosynthesis using detailed Chinese breast models
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作者 Jia-Hao Wang Rui Qiu +4 位作者 An-Kang Hu Ye-Qi Liu Zhen Wu Hui Zhang Jun-Li Li 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第5期42-59,共18页
The rise in breast cancer diagnoses among Chinese women has necessitated the use of X-ray breast screening,which carries a radiation risk.This study aimed to provide a dosimetry protocol for the Chinese female populat... The rise in breast cancer diagnoses among Chinese women has necessitated the use of X-ray breast screening,which carries a radiation risk.This study aimed to provide a dosimetry protocol for the Chinese female population to replace the traditional standard that utilizes simplified breast models,for the accurate estimation of the mean glandular dose of a patient undergoing digital breast tomosynthesis(DBT).The first set of detailed Chinese female breast models and representative breast parameters was constructed.Considering backscatter radiation and computational efficiency,we improved the combination of these models and the Chinese reference adult female whole-body voxel phantom.Image acquisition for four commercial DBT systems that are widely employed in China was simulated using the Monte Carlo method to obtain the normalized glandular dose coefficients of DBT(D_(gN)^(DBT))and the glandular depth dose(D_(g)^(dep)(z))for different breast characteristics and X-ray spectra.We calculated a series of D_(gN)^(DBT) values for breasts with different percentage mass glandularities(5%,25%,50%,75%,and 100%)and compressed breast thicknesses(2,3,4,5,6,and 7 cm)at various tube potentials(25,28,30,32,35,and 49 kV)and target/filter combinations(W/Rh,W/Al,Mo/Mo,Rh/Rh,and Rh/Ag).The parameter dependence of the breast characteristics and beam conditions on D_(gN)^(DBT) in detailed breast models was investigated.The D_(gN)^(DBT) results were 14.6-51.0%lower than those of the traditional dosimetry standard in China.The difference in D_(gN)^(DBT) was mainly due to a decrease in the depth of the main energy deposition area caused by the glandular distribution along the depth direction.The results obtained in this study may be used to improve breast dosimetry in China and provide more detailed information on risk assessment during DBT. 展开更多
关键词 Digital breast tomosynthesis Normalized glandular dose coefficients detailed breast model Monte Carlo simulation
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Clinical effects of detailed nursing management interventions on medication adherence and disease perception in patients with drugresistant tuberculosis
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作者 Yan-Li Chen Ya-Qin Xie +1 位作者 Ming-Yue Wei Dong-Mei Xu 《World Journal of Clinical Cases》 SCIE 2024年第20期4191-4198,共8页
BACKGROUND Tuberculosis(TB)is a chronic respiratory infectious disease that considerably jeopardizes human health,and there is no effective vaccine suitable for its prevention in the entire population.AIM To investiga... BACKGROUND Tuberculosis(TB)is a chronic respiratory infectious disease that considerably jeopardizes human health,and there is no effective vaccine suitable for its prevention in the entire population.AIM To investigate the promotion of medication adherence and disease cognition in patients with drug-resistant(DR-)TB using detailed nursing management.METHODS In total,114 patients with DR-TB who were diagnosed and treated at our hospital between January 2019 and January 2023 were included in this study.Patients in the control group(n=57)were managed with conventional nursing care,while those in the observation group(n=57)were managed with detailed nursing care.Medication adherence,disease awareness scores,medication safety,and nursing satisfaction were compared between the two groups after the intervention.RESULTS The post-intervention medication compliance rate was 91.23%in the observation group and 75.44%in the control group,with the former being 15.79%higher than the latter(P<0.05).There was no statistically significant difference in the disease awareness scores between the two groups before the intervention;the disease awareness scores of the observation group were significantly higher than those of the control group after the intervention(P<0.05).The incidence of gastrointestinal reactions,joint swelling and pain,hearing loss,electrolyte disorders,and liver and kidney function abnormalities were lower in the observation group than those in the control group.The total nursing satisfaction of the observation group was higher than that of the control group(P<0.05).CONCLUSION Implementation of detailed nursing management for patients with DR-TB can effectively improve medication adherence,enhance awareness of the disease,ensure safety of medication,and improve satisfaction with nursing care. 展开更多
关键词 Medication adherence detailed nursing management Drug-resistant tuberculosis Disease perception TUBERCULOSIS
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Exploration of Detailed Planning Practice of Chemical Industrial Parks under the Background of Territorial Space Planning
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作者 CHENG Xi 《Journal of Landscape Research》 2024年第4期51-54,共4页
With the gradual completion of the overall planning of city and county land space,the detailed planning will be prepared according to the requirements of transmitting and refining the upper planning.Industrial parks a... With the gradual completion of the overall planning of city and county land space,the detailed planning will be prepared according to the requirements of transmitting and refining the upper planning.Industrial parks are one of the“main forces”of local economic development,and the preparation of their detailed planning will escort their development.The key points of the Control Indicators of Construction Land in Industrial Projectsissued in 2008 and 2023 were compared,and the new requirements for detailed planning under the background of territorial space and the contradictions between the detailed planning of industrial parks and the overall planning of the upper territorial space were sorted out based on the summary of the existing problems in the development of chemical parks.It provides some ideas for the practice of detailed planning of chemical industrial parks under the background of territorial space. 展开更多
关键词 detailed planning Chemical industrial parks PRACTICE Territorial spatial planning
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Predicting distant metastasis in nasopharyngeal carcinoma using gradient boosting tree model based on detailed magnetic resonance imaging reports
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作者 Yu-Liang Zhu Xin-Lei Deng +7 位作者 Xu-Cheng Zhang Li Tian Chun-Yan Cui Feng Lei Gui-Qiong Xu Hao-Jiang Li Li-Zhi Liu Hua-Li Ma 《World Journal of Radiology》 2024年第6期203-210,共8页
BACKGROUND Development of distant metastasis(DM)is a major concern during treatment of nasopharyngeal carcinoma(NPC).However,studies have demonstrated im-proved distant control and survival in patients with advanced N... BACKGROUND Development of distant metastasis(DM)is a major concern during treatment of nasopharyngeal carcinoma(NPC).However,studies have demonstrated im-proved distant control and survival in patients with advanced NPC with the addition of chemotherapy to concomitant chemoradiotherapy.Therefore,precise prediction of metastasis in patients with NPC is crucial.AIM To develop a predictive model for metastasis in NPC using detailed magnetic resonance imaging(MRI)reports.METHODS This retrospective study included 792 patients with non-distant metastatic NPC.A total of 469 imaging variables were obtained from detailed MRI reports.Data were stratified and randomly split into training(50%)and testing sets.Gradient boosting tree(GBT)models were built and used to select variables for predicting DM.A full model comprising all variables and a reduced model with the top-five variables were built.Model performance was assessed by area under the curve(AUC).RESULTS Among the 792 patients,94 developed DM during follow-up.The number of metastatic cervical nodes(30.9%),tumor invasion in the posterior half of the nasal cavity(9.7%),two sides of the pharyngeal recess(6.2%),tubal torus(3.3%),and single side of the parapharyngeal space(2.7%)were the top-five contributors for predicting DM,based on their relative importance in GBT models.The testing AUC of the full model was 0.75(95%confidence interval[CI]:0.69-0.82).The testing AUC of the reduced model was 0.75(95%CI:0.68-0.82).For the whole dataset,the full(AUC=0.76,95%CI:0.72-0.82)and reduced models(AUC=0.76,95%CI:0.71-0.81)outperformed the tumor node-staging system(AUC=0.67,95%CI:0.61-0.73).CONCLUSION The GBT model outperformed the tumor node-staging system in predicting metastasis in NPC.The number of metastatic cervical nodes was identified as the principal contributing variable. 展开更多
关键词 Nasopharyngeal carcinoma Distant metastasis Machine learning detailed magnetic resonance imaging report Gradient boosting tree model
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Fame:A Fast Detailed Placement Algorithm for Standard\| Cell Layout Based on Mixed Mincut and Enumeration 被引量:1
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作者 姚波 侯文婷 +1 位作者 洪先龙 蔡懿慈 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2000年第8期744-753,共10页
Rapid progress in manufacturing greatly challenges to the VLSI physical design in both speed and performance. A fast detailed placement algorithm, FAME is presented in this paper, according to these demands. It inhe... Rapid progress in manufacturing greatly challenges to the VLSI physical design in both speed and performance. A fast detailed placement algorithm, FAME is presented in this paper, according to these demands. It inherits the optimal positions of cells given by a global placer and exact position to each cell by local optimization. FM Mincut heuristic and local enumeration are used to optimize the total wirelength in y and x directions respectively, and a two way mixed optimizing flow is adopted to combine the two methods for a better performance. Furthermore, a better enumeration strategy is introduced to speed up the algorithm. An extension dealing with blockages in placement has also been discussed. Experimental results show that FAME runs 4 times faster than RITUAL and achieves a 5% short in total wirelength on average. 展开更多
关键词 detailed placement layout VLSI mincut optimization
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Detailed Routing Algorithm with Optical Proximity Effects Constraint 被引量:1
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作者 周强 蔡懿慈 +1 位作者 张为 洪先龙 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第2期189-195,共7页
We present a detailed routing algorithm considering the optical proximity effect. The light intensity is calculated beforehand and stored in look-up tables. These costs are used as a constraint to guide the sequential... We present a detailed routing algorithm considering the optical proximity effect. The light intensity is calculated beforehand and stored in look-up tables. These costs are used as a constraint to guide the sequential routing. The routing algorithm is based on constructed force directed Steiner tree routing to enhance routing efficien- cy. Experimental results on industrial benchmark circuits show that the presented routing algorithm can obtain much improvement considering optical effects short runtime. 展开更多
关键词 optical proximity effect detailed routing Steiner tree YIELD
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Better Initial Placement Algorithm for Large-Scale Mixed-Mode Detailed Placement
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作者 周强 罗丽娟 +1 位作者 洪先龙 周汉斌 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2004年第7期784-789,共6页
An algorithm is presented for better legal solution in detailed placement of large scale mixed macros and standard cells IC design.Due to the limitation of computing complexity,an effective and efficient initial place... An algorithm is presented for better legal solution in detailed placement of large scale mixed macros and standard cells IC design.Due to the limitation of computing complexity,an effective and efficient initial placement is very important for detailed placement.Novelty of this algorithm lies in a better solution at initial stage by using network flow method to satisfy row capacity constraint and the thought of linear placement problem(LPP) to resolve overlaps.Moreover,divide and conquer strategy and other simplified methods are adopted to minimize complexity.Experimental results show that the algorithm can get an average of 16% wire length improvement on PAFLO in reasonable CPU time. 展开更多
关键词 PLACEMENT detailed placement mixed mode placement ALGORITHM
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Quantitative method for evaluating detailed volatility of wind power at multiple temporal-spatial scales 被引量:6
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作者 Yongqian Liu Han Wang +3 位作者 Shuang Han Jie Yan Li Li Zixin Chen 《Global Energy Interconnection》 2019年第4期318-327,共10页
With the increasing proportion of wind power integration, the volatility of wind power brings huge challenges to the safe and stable operation of the electric power system. At present, the indexes commonly used to eva... With the increasing proportion of wind power integration, the volatility of wind power brings huge challenges to the safe and stable operation of the electric power system. At present, the indexes commonly used to evaluate the volatility of wind power only consider its overall characteristics, such as the standard deviation of wind power, the average of power variables, etc., while ignoring the detailed volatility of wind power, that is, the features of the frequency distribution of power variables. However, how to accurately describe the detailed volatility of wind power is the key foundation to reduce its adverse influences. To address this, a quantitative method for evaluating the detailed volatility of wind power at multiple temporal-spatial scales is proposed. First, the volatility indexes which can evaluate the detailed fluctuation characteristics of wind power are presented, including the upper confidence limit, lower confidence limit and confidence interval of power variables under the certain confidence level. Then, the actual wind power data from a location in northern China is used to illustrate the application of the proposed indexes at multiple temporal(year–season–month–day) and spatial scales(wind turbine–wind turbines–wind farm–wind farms) using the calculation time windows of 10 min, 30 min, 1 h, and 4 h. Finally, the relationships between wind power forecasting accuracy and its corresponding detailed volatility are analyzed to further verify the effectiveness of the proposed indexes. The results show that the proposed volatility indexes can effectively characterize the detailed fluctuations of wind power at multiple temporal-spatial scales. It is anticipated that the results of this study will serve as an important reference for the reserve capacity planning and optimization dispatch in the electric power system which with a high proportion of renewable energy. 展开更多
关键词 Wind power detailed VOLATILITY Frequency distribution MULTIPLE temporal-spatial scales TYPICAL DAYS Forecasting accuracy
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Development and testing of a detailed kinetic mechanism of natural gas combustion in internal combustion engine 被引量:2
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作者 M.Mansha A.R.Saleemi +1 位作者 Badar M.Ghauri Naveed Ramzan 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2010年第2期97-106,共10页
A detailed chemical mechanism to describe the combustion of natural gas in internal combustion (IC) engine has been developed,which is consisting of 233 reversible reactions and 79 species.This mechanism accounts fo... A detailed chemical mechanism to describe the combustion of natural gas in internal combustion (IC) engine has been developed,which is consisting of 233 reversible reactions and 79 species.This mechanism accounts for the oxidation of methane,ethane,propane and nitrogen.It has been tested using IC engine model of CHEMKIN 4.1.1 and experimental measurements.The performance of the proposed mechanism was evaluated at various equivalence ratios (φ=0.6 to φ=1.3),initial reactor conditions (Tini=500 to 3500 ℃; Pini=1.0 to 10 atm) and engine speed (2000-7000 rpm).The proposed kinetic mechanism shows good concordances with GRI3.0 mechanism especially in the prediction of temperature,pressure and major product species (H2O,CO2) profiles at stoichiometric conditions (φ=1.0).The experimental results of measured cylinder pressure,species fractions were also in agreement with simulation results derived from the proposed kinetic mechanism.The proposed mechanism successfully predicts the formation of gaseous pollutants (CO,NO,NO2,NH3) in the engine exhaust.Although there are some discrepancies among each simulation profile,the proposed detailed mechanism is good to represent the combustion of natural gas in IC engine. 展开更多
关键词 natural gas detailed mechanism equivalence ratio pollutants emission COMBUSTION
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Perovskite/Silicon Tandem Solar Cells: From Detailed Balance Limit Calculations to Photon Management 被引量:2
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作者 Mohammad I.Hossain Wayesh Qarony +3 位作者 Sainan Ma Longhui Zeng Dietmar Knipp Yuen Hong Tsang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2019年第4期49-72,共24页
Energy conversion efficiency losses and limits of perovskite/silicon tandem solar cells are investigated by detailed balance calculations and photon management.An extended Shockley-Queisser model is used to identify f... Energy conversion efficiency losses and limits of perovskite/silicon tandem solar cells are investigated by detailed balance calculations and photon management.An extended Shockley-Queisser model is used to identify fundamental loss mechanisms and link the losses to the optics of solar cells.Photon management is used to minimize losses and maximize the energy conversion efficiency.The influence of photon management on the solar cell parameters of a perovskite single-junction solar cell and a perovskite/silicon solar cell is discussed in greater details.An optimized solar cell design of a perovskite/silicon tandem solar cell is presented,which allows for the realization of solar cells with energy conversion efficiencies exceeding 32%. 展开更多
关键词 PEROVSKITE SOLAR CELL Tandem SOLAR CELL Thermodynamic PHOTON MANAGEMENT detailed balance LIMIT
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Comparison of endoscopic ultrasound, computed tomography and magnetic resonance imaging in assessment of detailed structures of pancreatic cystic neoplasms 被引量:13
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作者 Chen Du Ning-Li Chai +6 位作者 En-Qiang Linghu Hui-Kai Li Li-Hua Sun Lei Jiang Xiang-Dong Wang Ping Tang Jing Yang 《World Journal of Gastroenterology》 SCIE CAS 2017年第17期3184-3192,共9页
AIM To evaluate the advantages of endoscopic ultrasound(EUS) in the assessment of detailed structures of pancreatic cystic neoplasms(PCNs) compared to computed tomography(CT) and magnetic resonance imaging(MRI).METHOD... AIM To evaluate the advantages of endoscopic ultrasound(EUS) in the assessment of detailed structures of pancreatic cystic neoplasms(PCNs) compared to computed tomography(CT) and magnetic resonance imaging(MRI).METHODS All patients with indeterminate PCNs underwent CT, MRI, and EUS. The detailed information, including size, number, the presence of a papilla/nodule, the presence of a septum, and the morphology of the pancreatic duct of PCNs were compared among the three imaging modalities. The size of each PCN was determined using the largest diameter measured. A cyst consisting of several small cysts was referred to as a motherdaughter cyst. Disagreement among the three imaging modalities regarding the total number of mother cysts resulted in the assumption that the correct number was the one in which the majority of imaging modalities indicated.RESULTS A total of 52 females and 16 males were evaluated. The median size of the cysts was 42.5 mm by EUS, 42.0 mm by CT and 38.0 mm by MRI; there was no significant difference in size as assessed among the three imaging techniques. The diagnostic sensitivity and ability of EUS to classify PCNs were 98.5%(67/68) and 92.6%(63/68), respectively. These percentages were higher than those of CT(73.1%, P < 0.001; 17.1%, P < 0.001) and MRI(81.3%, P = 0.001; 20.3%, P < 0.001). EUS was also able to better assess the number of daughter cysts in mother cysts than CT(P = 0.003); however, there was no significant difference between EUS and MRI in assessing mother-daughter cysts(P = 0.254). The papilla/nodule detection rate by EUS was 35.3%(24/68), much higher than those by CT(5.8%, 3/52) and MRI(6.3%, 4/64). The detection rate of the septum by EUS was 60.3%(41/68), which was higher than those by CT(34.6%, 18/52) and by MRI(46.9%, 30/64); the difference between EUS and CT was significant(P = 0.02). The rate of visualizing the pancreatic duct using EUS was 100%, whereas using CT and MRI it was less than 10%.CONCLUSION EUS helps visualize the detailed structures of PCNs and has many advantages over CT and MRI. EUS is valuable in the diagnosis and assessment of PCNs. 展开更多
关键词 Endoscopic ultrasound detailed structures Computed tomography Magnetic resonance imaging Pancreatic cystic neoplasms
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Detailed sedimentary facies of a sandstone reservoir in the eastern zone of the Sulige gas field, Ordos Basin 被引量:10
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作者 LI Yijun ZHAO Yong +2 位作者 YANG Renchao FAN Aiping LI Fuping 《Mining Science and Technology》 EI CAS 2010年第6期891-897,903,共8页
Given sustaining exploration, the eastern zone of the Sulige gas field may soon become a key area of exploitation. In order to explore its genesis, types and distribution of the reservoir sandstones in the eastern zon... Given sustaining exploration, the eastern zone of the Sulige gas field may soon become a key area of exploitation. In order to explore its genesis, types and distribution of the reservoir sandstones in the eastern zone of this gas field, we focused in our study on the provenance and detailed sedimentary facies of sandstone of the He8 (the eighth part of the Shihezi formation, Permian system) and Shanxil (the first part of the Shanxi formation, Permian system) members, based on core observations, analyses in petrography, granularity and logging. The results show that: 1) the sandstone provenance of Shanxil and He8 in the eastern zone of the Sulige gas field is from the north of the Ordos Basin, characterized by dual directions from the north and northeast. 2) The He8 and Shanxil members were deposited in a fluvial-delta sedimentary system. The He8 was mainly deposited in braided rivers, in- cluding braided channels, channel bars, levee and floodplain sub-environments, whereas the Shanxil Member was deposited in braided rivers and deltas, including braided channels, channel bars, floodplains, tributaries and inter-tributary sub-environments. 3) Sedimentary facies bands migrated in drastic fashion towards the basin from the Shanxil to the He8 Member. Base levels of sedi- mentation generally present a trend of small increases in-amplitude, large decreasing amplitudes and slow and gradual Increases. 4) The continuity of the reservoir sandbodies along the source direction is better than that perpendicular to the direction. Compared with Shanxil, both dimensions and continuity of the sandbodies in He8 are better from which we conclude that it is the most fa- vorable part of the reservoir. 展开更多
关键词 Ordos Basin Sulige gas field PERMIAN sandstone reservoir detailed sedimentary facies
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CFD Simulation of Propane Cracking Tube Using Detailed Radical Kinetic Mechanism 被引量:7
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作者 张楠 邱彤 陈丙珍 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第12期1319-1331,共13页
In the radiant section of cracking furnace,the thermal cracking process is highly coupled with turbulent flow,heat transfer and mass transfer.In this paper,a three-dimensional simulation of propane pyrolysis reactor t... In the radiant section of cracking furnace,the thermal cracking process is highly coupled with turbulent flow,heat transfer and mass transfer.In this paper,a three-dimensional simulation of propane pyrolysis reactor tube is performed based on a detailed kinetic radical cracking scheme,combined with a comprehensive rigorous computational fluid dynamics(CFD)model.The eddy-dissipation-concept(EDC)model is introduced to deal with turbulence-chemistry interaction of cracking gas,especially for the multi-step radical kinetics.Considering the high aspect ratio and severe gradient phenomenon,numerical strategies such as grid resolution and refinement,stepping method and relaxation technique at different levels are employed to accelerate convergence.Large scale of radial nonuniformity in the vicinity of the tube wall is investigated.Spatial distributions of each radical reaction rate are first studied,and made it possible to identify the dominant elementary reactions.Additionally,a series of operating conditions including the feedstock feed rate,wall temperature profile and heat flux profile towards the reactor tubes are investigated.The obtained results can be used as scientific guide for further technical retrofit and operation optimization aiming at high conversion and selectivity of pyrolysis process. 展开更多
关键词 numerical simulation cracking tube computational fluid dynamics(CFD) detailed radical kinetics
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Reduced Detailed Mechanism for Methane Combustion 被引量:1
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作者 Abdelouahad Ait Msaad Abdeltif Belcadi +2 位作者 Mustapha Mahdaoui Elhoussin Aaffad M’hamed Mouqallid 《Energy and Power Engineering》 2012年第1期28-33,共6页
Simulated results from a detailed elementary reaction mechanism for methane-containing species in flames consisting of nitrogen (NOx), C1 or C2 fuels are presented, and compared with reduced mechanism;this mechanism h... Simulated results from a detailed elementary reaction mechanism for methane-containing species in flames consisting of nitrogen (NOx), C1 or C2 fuels are presented, and compared with reduced mechanism;this mechanism have been constructed with the analysis of the rate sensitivity matrix f (PCAF method), and the computational singular perturbation (CSP). The analysis was performed on solutions of unstrained adiabatic premixed flames with detailed chemical kinetics described by GRI 3.0 for methane including NOx formation. A 9-step reduced mechanism for methane has been constructed which reproduces accurately laminar burning velocities, flame temperatures and mass fraction distributions of major species for the whole flammability range. Many steady-state species are also predicted satisfactorily. This mechanism is especially for lean flames. This mechanism is accurate for a wide range of the equivalence ratio (1, 0.9, 0.8, and 0.7) and for pressures as high as 40 atm to 60 atm. For both fuels, the CSP algorithm automatically pointed to the same steady-state species as those identified by laborious analysis or intuition in the literature and the global reactions were similar to well established previous methane-reduced mechanisms. This implies that the method is very well suited for the study of complex mechanisms for heavy hydrocarbon combustion. 展开更多
关键词 detailed MECHANISM REDUCED MECHANISM PCAF METHOD CSP ALGORITHM
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ARCHITECTURE MODEL AND RESOURCE GRAPH BUILDING ALGORITHM FOR DETAILED FPGA ARCHITECTURE DESIGN 被引量:1
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作者 Li Zhihua Yang Haigang +2 位作者 Yang Liqun Li Wei Huang Juan 《Journal of Electronics(China)》 2014年第6期505-512,共8页
This paper addresses the issue of designing the detailed architectures of Field-Programmable Gate Arrays(FPGAs), which has a great impact on the overall performances of an FPGA in practice. Firstly, a novel FPGA archi... This paper addresses the issue of designing the detailed architectures of Field-Programmable Gate Arrays(FPGAs), which has a great impact on the overall performances of an FPGA in practice. Firstly, a novel FPGA architecture description model is proposed based on an easy-to-use file format known as YAML. This format permits the description of any detailed architecture of hard blocks and channels. Then a general algorithm of building FPGA resource graph is presented. The proposed model is scalable and capable of dealing with detailed architecture design and can be used in FPGA architecture evaluation system which is developed to enable detailed architecture design. Experimental results show that a maximum of 16.36% reduction in total wirelength and a maximum of 9.34% reduction in router effort can be obtained by making very little changes to detailed architectures, which verifies the necessity and effectiveness of the proposed model. 展开更多
关键词 Field-Programmable Gate Arrays(FPGAs) architecture model detailed architecture design Architecture evaluation system
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Mapping Detailed Soil Property Using Small Scale Soil Type Maps and Sparse Typical Samples 被引量:2
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作者 ZHANG Shujie ZHU Axing +2 位作者 LIU Wenliang LIU Jing YANG Lin 《Chinese Geographical Science》 SCIE CSCD 2013年第6期680-691,共12页
Soil type maps at the scale of I Z 1 000 000 are used extensively to provide soil spatial distribution information for soil erosion assessment and watershed management models in China. However, the soil property maps ... Soil type maps at the scale of I Z 1 000 000 are used extensively to provide soil spatial distribution information for soil erosion assessment and watershed management models in China. However, the soil property maps produced through conventional direct linking method usually suffer low accuracy as well as the lack of spatial details within a soil type polygon. This paper presents an effective method to produce detailed soil property map based on representative samples which were extracted from each polygon on the 1 : 1 000 000 soil type map. The representative sample of each polygon is defined as the location that can represent the largest area within the polygon. The representativeness of a candidate sample is determined by calculating the soil-forming environment condition similarities between the sample and other locations. Once the representative sample of each polygon has been chosen, the property values of the existing typical samples are assigned to the corresponding representative samples with the same soil type. Finally, based on these representative samples, the detailed soil property map could be produced by using existing digital soil mapping methods. The case study in XuanCheng City, Anhui Province of China, demonstrated the proposed method could produce soil property map at a higher level of spatial details and accuracy: 1) The soil organic matter (SOM) map produced based on the representative samples can not only depict the detailed spatial distribution of SOM within a soil type polygon but also largely reduce the abrupt change of soil property at the boundaries of two adjacent polygons. 2) The Root Mean Squared Error (RMSE) of the SOM map based on the representative samples is 1.61, and it is 1.37 for the SOM map produced by using conventional direct linking method. Therefore, the proposed method is an effective approach to produce spatial detailed soil property map with higher accuracy for environment simulation models. 展开更多
关键词 soil type map existing typical sample representative sample detailed soil property map digital soil mapping
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Coupled simulation of recirculation zonal firebox model and detailed kinetic reactor model in an industrial ethylene cracking furnace 被引量:8
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作者 Zhou Fang Tong Qiu Weiguo Zhou 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2017年第8期1091-1100,共10页
A coupled system simulating both firebox and reactor is established to study the naphtha pyrolysis in an industrial tubular furnace.The firebox model is based on zone method including combustion,radiation,and convecti... A coupled system simulating both firebox and reactor is established to study the naphtha pyrolysis in an industrial tubular furnace.The firebox model is based on zone method including combustion,radiation,and convection to simulate heat transfer in the furnace.A two-dimensional recirculation model is proposed to estimate the flow field in furnace.The reactor model integrates the feedstock reconstruction model,an auto-generator of detail kinetic schemes,and the reactor simulation model to simulate the reaction process in the tubular coil.The coupled simulation result is compared with industrial process and shows agreement within short computation time. 展开更多
关键词 Ethylene cracking Coupled simulation Tubular furnace Recirculation zone modeling detailed reaction kinetic
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Detailed reservoir inversion addressing geological problems in reservoir development 被引量:1
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作者 Shen Guoqiang Meng Xianjun Xia Jizhuang Zhang Xuefang Li Xia 《Applied Geophysics》 SCIE CSCD 2007年第1期58-65,共8页
In the Ken 71 development block, fluvial facies of the Neogene Guantao Formation and delta facies of the Paleogene Dongying Formation are the main pay beds. It is a multiple oil and water system which is complicated b... In the Ken 71 development block, fluvial facies of the Neogene Guantao Formation and delta facies of the Paleogene Dongying Formation are the main pay beds. It is a multiple oil and water system which is complicated by faults. Characteristics of the block include a dense well network, thin reservoirs, complicated horizontal relationships, and small velocity difference between reservoir and non-reservoir. Therefore, it is difficult to conduct detailed reservoir description for subsequent development project adjustment. We demonstrate a stochastic seismic inversion which aims at detailed reservoir description. It is a technology which utilizes multiple wells, seismic data, and geological calibration and integrates with 3D structural interpretation results to build a 3D multi-fault detailed and constrained geological model. On this basis, we adopted stochastic seismic inversion to conduct a multi-stratum parameters inversion such as impedance and lithology. As a result, thin interbedded strata in the block were well resolved and the results demonstrated the importance of detailed reservoir inversion for oilfield development. 展开更多
关键词 Ken 71 block multi-well calibration detailed geological model IMPEDANCE stochastic seismic inversion
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Detailed balance limit efficiency of silicon intermediate band solar cells
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作者 曹权 马志华 +2 位作者 薛春来 左玉华 王启明 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第9期334-338,共5页
The detailed balance method is used to study the potential of the intermediate band solar cell (IBSC), which can improve the efficiency of the gi-based solar cell with a bandgap between 1.1 eV to 1.7 eV. It shows th... The detailed balance method is used to study the potential of the intermediate band solar cell (IBSC), which can improve the efficiency of the gi-based solar cell with a bandgap between 1.1 eV to 1.7 eV. It shows that a crystalline silicon solar ceil with an intermediate band located at 0.36 eV below the conduction band or above the valence band can reach a limiting efficiency of 54% at the maximum light concentration, improving greatly than 40.7% of the Shoekley-Queisser limit for the single junction Si solar cell. The simulation also shows that the limiting efficiency of the silicon-based solar cell increases as the bandgap increases from 1.1 eV to 1.7 eV, and the amorphous Si solar cell with a bandgap of 1.7 eV exhibits a radiative limiting efficiency of 62.47070, having a better potential. 展开更多
关键词 intermediate band silicon solar cell concentrated light detailed balance principle
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