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Concise extraction and characterization of the pore-throat network in unconventional hydrocarbon reservoirs: A new perspective
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作者 Shu-Heng Du Yong-Min Shi 《Petroleum Science》 SCIE EI CAS CSCD 2024年第3期1474-1487,共14页
In this study,a new image-based method for the extraction and characterization of pore-throat network for unconventional hydrocarbon storage and exploitation is proposed.“Pore-throat solidity”,which is analogous to ... In this study,a new image-based method for the extraction and characterization of pore-throat network for unconventional hydrocarbon storage and exploitation is proposed.“Pore-throat solidity”,which is analogous to particle solidity,and a new method for automatic identification of pores and throats in tight sandstone oil reservoirs are introduced.Additionally,the“pore-throat combination”and“pure pore”are defined and distinguished by drawing the cumulative probability curve of the pore-throat solidity and by selecting an appropriate cutoff point.When the discrete grid set is recognized as a pore-throat combination,Legendre ellipse fitting and minimum Feret diameter are used.When the pore and throat grid sets are identified as pure pores,the pore diameter can be directly calculated.Using the new method,the analytical results for the physical parameters and pore radius agree well with most prior studies.The results comparing the maximum ball and the new model could also prove the accuracy of the latter's in micro and nano scales.The new model provides a more practical theoretical basis and a new calculation method for the rapid and accurate evaluation of the complex processes of oil migration. 展开更多
关键词 Hydrocarbon exploitation PORE throat Porous media Identification
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Hydrodynamic resistance of pore–throat structures and its effect on shale oil apparent permeability
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作者 Wendong Wang Qian Zhang +3 位作者 Jilong Xu Da Zheng Lifeng Liu Yuliang Su 《International Journal of Coal Science & Technology》 EI CAS CSCD 2024年第2期101-110,共10页
Oil transport is greatly affected by heterogeneous pore–throat structures present in shale.It is therefore very important to accurately characterize pore–throat structures.Additionally,it remains unclear how pore–t... Oil transport is greatly affected by heterogeneous pore–throat structures present in shale.It is therefore very important to accurately characterize pore–throat structures.Additionally,it remains unclear how pore–throat structures affect oil transport capacity.In this paper,using finite element(FE)simulation and mathematical modeling,we calculated the hydrodynamic resistance for four pore–throat structure.In addition,the influence of pore throat structure on shale oil permeability is analyzed.According to the results,the hydrodynamic resistance of different pore throat structures can vary by 300%.The contribution of additional resistance caused by streamline bending is also in excess of 40%,even without slip length.Fur-thermore,Pore–throat structures can affect apparent permeability by more than 60%on the REV scale,and this influence increases with heterogeneity of pore size distribution,organic matter content,and organic matter number.Clearly,modeling shale oil flow requires consideration of porous–throat structure and additional resistance,otherwise oil recovery and flow capacity may be overestimated. 展开更多
关键词 Pore–throat structure Hydrodynamic resistance Apparent permeability REV-scale Shale oil
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Simulation Study of Solid Rocket Motor C/C Throat Liner Ablation Based on Two Regions
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作者 Guanneng Chen Yihua Xu +2 位作者 Xiaojiang Zha Hemeng Shi Bing Liu 《Journal of Power and Energy Engineering》 2024年第4期1-19,共19页
Based on the ablation micro-morphological characteristics, thermo-chemical ablation mechanism, and mechanical stripping mechanism, a dual-region solid rocket motor C/C throat liner ablation model and physical model ar... Based on the ablation micro-morphological characteristics, thermo-chemical ablation mechanism, and mechanical stripping mechanism, a dual-region solid rocket motor C/C throat liner ablation model and physical model are established. The ablation program was written and the experimental data of 70 lb BATES engine platform was used for model validation. The relative errors between the simulation calculation results and the experimental results were −6.83% - 10.20%. The ablation program was applied to study the effects of combustion chamber temperature, pressure, oxidation component concentration, throat particle concentration and particle scouring angle on the nozzle throat liner, which provides a reference for the design of the nozzle throat liner and the estimation of solid rocket motor ablation. 展开更多
关键词 Dual-Area Ablation Model C/C throat Liner Ablation Environment Ablation Program
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Severe Cut Throat Injury in a Child: A Case Report and Review of Literature
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作者 Nafisatu Bello-Muhammad Hamisu Abdullahi +3 位作者 Yasir Nuhu Jibril Auwal Adamu Manir Hamza Anka Muhammad Ghazali Hasheem 《International Journal of Otolaryngology and Head & Neck Surgery》 2024年第4期285-292,共8页
Background: Cut-throat injury is a potentially fatal condition that may be associated with serious morbidity and mortality. The neck region is particularly at risk of serious injuries due to the location of vital stru... Background: Cut-throat injury is a potentially fatal condition that may be associated with serious morbidity and mortality. The neck region is particularly at risk of serious injuries due to the location of vital structures, including nerves, viscera, and major vessels. Although cut-throat injury is said to be rare in children, its occurrence has been reported in some series. Management of this condition requires a multidisciplinary approach for a better outcome. Aim: The aim of this report is to highlight the successful management of an alarming case of severe cut-throat injury with associated laryngeal injury in a child. Case presentation: A 12-year-old boy presented with a cut-throat following an assault by an unknown person. Examination revealed an acutely ill child, conscious but pale. He sustained a deep transverse laceration that transected the thyroid cartilage, exposing the laryngeal cavity. An assessment of Zone II penetrating neck injury was made. He was resuscitated, and had emergency neck exploration, tracheostomy, and repair of the injuries. The patient was followed up for 6 months, and had a good voice outcome, with no significant complication. Conclusion: Cut-throat injury is rare in children. But it is a potentially life-threatening condition. It is therefore important to recognize this entity and develop effective protocol of management in our environment. 展开更多
关键词 Cut-throat Neck Trauma Penetrating Neck Injury Neck Exploration TRACHEOSTOMY
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Pore-Throat Combination Types and Gas-Water Relative Permeability Responses of Tight Gas Sandstone Reservoirs in the Zizhou Area of East Ordos Basin, China 被引量:5
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作者 LI Mi GUO Yinghai +2 位作者 LI Zhuangfu WANG Huaichang ZHANG Jingxia 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2019年第3期622-636,共15页
With the aim of better understanding the tight gas reservoirs in the Zizhou area of east Ordos Basin,a total of 222 samples were collected from 50 wells for a series of experiments.In this study,three pore-throat comb... With the aim of better understanding the tight gas reservoirs in the Zizhou area of east Ordos Basin,a total of 222 samples were collected from 50 wells for a series of experiments.In this study,three pore-throat combination types in sandstones were revealed and confirmed to play a controlling role in the distribution of throat size and the characteristics of gas-water relative permeability.The type-I sandstones are dominated by intercrystalline micropores connected by cluster throats,of which the distribution curves of throat size are narrow and have a strong single peak(peak ratio>30%).The pores in the type-II sandstones dominantly consist of secondary dissolution pores and intercrystalline micropores,and throats mainly occur as slice-shaped throats along cleavages between rigid grain margins and cluster throats in clay cement.The distribution curves of throat size for the type-II sandstones show a bimodal distribution with a substantial low-value region between the peaks(peak ratio<15%).Primary intergranular pores and secondary intergranular pores are mainly found in type-III samples,which are connected by various throats.The throat size distribution curves of type-III sandstones show a nearly normal distribution with low kurtosis(peak ratio<10%),and the micro-scale throat radii(>0.5μm)constitute a large proportion.From type-I to type-III sandstones,the irreducible water saturation(Swo)decreased;furthermore,the slope of the curves of Krw/Krg in two-phase saturation zone decreased and the two-phase saturation zone increased,indicating that the gas relative flow ability increased.Variations of the permeability exist in sandstones with different porethroat combination types,which indicate the type-III sandstones are better reservoirs,followed by type-II sandstones and type-I sandstones.As an important factor affecting the reservoir quality,the pore-throat combination type in sandstones is the cumulative expression of lithology and diagenetic modifications with strong heterogeneity. 展开更多
关键词 tight gas sandstone pore-throat COMBINATION type throat characteristic GAS-WATER relative permeability Zizhou area ORDOS Basin
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Pore throat structure heterogeneity and its effect on gas-phase seepage capacity in tight sandstone reservoirs:A case study from the Triassic Yanchang Formation,Ordos Basin 被引量:1
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作者 Yu-Bin Yang Wen-Lian Xiao +8 位作者 Ling-Li Zheng Qi-Hong Lei Chao-Zhong Qin You-An He Shuai-Shuai Liu Min Li Yong-Ming Li Jin-Zhou Zhao Meng Chen 《Petroleum Science》 SCIE EI CSCD 2023年第5期2892-2907,共16页
The microscopic heterogeneity of pore-throat structures in tight sandstone is a crucial parameter for understanding the transport mechanism of fluid flow.In this work,we firstly developed the new procedure to characte... The microscopic heterogeneity of pore-throat structures in tight sandstone is a crucial parameter for understanding the transport mechanism of fluid flow.In this work,we firstly developed the new procedure to characterize the pore size distribution(PSD)and throat size distribution(TSD)by combining the nuclear magnetic resonance(NMR),cast thin section(CTS),and constant-rate mercury injection(CRMI)tests,and used the permeability estimated model to verify the full-scale PSD and TSD.Then,we respectively analyzed the fractal feature of the pore and throat,and characterized the heterogeneity of pores and throats.Finally,we elaborated the effect of the pore and throat heterogeneity on the gas-phase seepage capacity base on the analysis of the simple capillary tube model and gas-flooding experiment.The results showed that(1)The PSD and TSD of the tight sandstone sample ranged from 0.01 to 10 mm and from 0.1 to 57 mm,respectively,mainly contributed by the micropores and mesopores.Meanwhile,the permeability estimated by the PSD and TSD was consistent with the experimental permeability,and relative error was lower than 8%.(2)The PSD and TSD exhibited multifractal characteristics,and singularity strength range,Δα,could be used as the indicator for characterizing the heterogeneity of pore and throat.Furthermore,the throat of the sample showed stronger heterogeneity than that the pore.(3)The throats played an important role for the fluid transport in the tight sandstone,and the effect of the throat heterogeneity on the gas-phase seepage capacity was different under the lower and higher injection pressure.The macropores and micropores maybe respectively become the preferential migration pathways at the lower and higher injection pressure.In the end,the identification plate was established in our paper,and could be described the relationship among the throat heterogeneity,injection pressure,permeability and flow path of the gas phase in the tight sandstone. 展开更多
关键词 Tight sandstone Pore size distribution(PSD) throat size distribution(TSD) Pore and throat heterogeneity Gas-phase flow capacity Nuclear magnetic resonance(NMR) Constant-rate mercury injection(CRMI)
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Classification and control factors of pore-throat systems in hybrid sedimentary rocks of Jimusar Sag, Junggar Basin, NW China
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作者 XIAO Dianshi GAO Yang +3 位作者 PENG Shouchang WANG Meng WANG Min LU Shuangfang 《Petroleum Exploration and Development》 CSCD 2021年第4期835-849,共15页
Aiming at the complicated problem of the genesis of high-quality hybrid sedimentary rocks,the pore-throat systems,controlling factors and fluid mobility of hybrid sedimentary rocks in the Permian Lucaogou Formation in... Aiming at the complicated problem of the genesis of high-quality hybrid sedimentary rocks,the pore-throat systems,controlling factors and fluid mobility of hybrid sedimentary rocks in the Permian Lucaogou Formation in Jimusar Sag were examined.The results show that the hybrid sedimentary rocks contain 5 types of pore-throat system,intergranular(Type A),mixed intergranular-dissolved-intercrystalline(Type B),dissolved(Type C),mixed dissolved-intercrystalline(Type D)and intercrystalline(Type E)ones.The pore-throat systems are controlled by 3 major factors,the component content and arrangement(CCA)of hybrid sedimentary rocks,sedimentary environment and diagenesis.CCA controls the matrix support mode of hybrid sedimentary rocks,and therefore controls the types and changes of pore-throat system.The sedimentary environment mainly controls the macroscopic distribution of pore-throat system,i.e.,hybrid sedimentary rocks deposited in the near source and high-energy environment are characterized by high content of coarse-grained component,granular/interbedded-support mode,and development of Type A and Type B pore-throat systems.Hybrid sedimentary rocks deposited in the medium-energy environment far from source are characterized by dolomitic/mud support mode and Type C and Type D pore-throat systems.Hybrid sedimentary rocks deposited in low-energy environment far from source have mainly Type E and Type D pore-throat systems.Diagenetic processes such as compaction and calcite cementation make the proportions of Type A and Type C pore-throat systems decrease further.In the hybrid sedimentary process of sandy-mud,pore-throat system types show a change of"A→B→C→D",in that of dolomite-sand,pore-throat system types show a change of"A→C→D→E"or"B→D→E",and in that of dolomite-mud,pore-throat system types show a change of"D→E",which are affected in details by the contents of coarse-grain component,feldspar and dolomite.The reservoir with Type A pore-throats has the best physical properties and fluid mobility,and the reservoirs with Type D and Type E pore-throats have the poorest.The movable fluid distribution is related to the matrix support mode,and the larger pores in hybrid sedimentary rocks of dolomite/mud support mode have no obvious advantage in fluid mobility.The findings of this study provide a geological basis for evaluating and building reasonable interpretation model of hybrid sedimentary rocks sweet spot. 展开更多
关键词 pore throat system pore throat types evolution fluid mobility hybrid sedimentary rock Permian Lucaogou Formation Jimusar Sag Junggar Basin
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Hybrid Dipper Throated and Grey Wolf Optimization for Feature Selection Applied to Life Benchmark Datasets 被引量:2
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作者 Doaa Sami Khafaga El-Sayed M.El-kenawy +4 位作者 Faten Khalid Karim Mostafa Abotaleb Abdelhameed Ibrahim Abdelaziz A.Abdelhamid D.L.Elsheweikh 《Computers, Materials & Continua》 SCIE EI 2023年第2期4531-4545,共15页
Selecting the most relevant subset of features from a dataset is a vital step in data mining and machine learning.Each feature in a dataset has 2n possible subsets,making it challenging to select the optimum collectio... Selecting the most relevant subset of features from a dataset is a vital step in data mining and machine learning.Each feature in a dataset has 2n possible subsets,making it challenging to select the optimum collection of features using typical methods.As a result,a new metaheuristicsbased feature selection method based on the dipper-throated and grey-wolf optimization(DTO-GW)algorithms has been developed in this research.Instability can result when the selection of features is subject to metaheuristics,which can lead to a wide range of results.Thus,we adopted hybrid optimization in our method of optimizing,which allowed us to better balance exploration and harvesting chores more equitably.We propose utilizing the binary DTO-GW search approach we previously devised for selecting the optimal subset of attributes.In the proposed method,the number of features selected is minimized,while classification accuracy is increased.To test the proposed method’s performance against eleven other state-of-theart approaches,eight datasets from the UCI repository were used,such as binary grey wolf search(bGWO),binary hybrid grey wolf,and particle swarm optimization(bGWO-PSO),bPSO,binary stochastic fractal search(bSFS),binary whale optimization algorithm(bWOA),binary modified grey wolf optimization(bMGWO),binary multiverse optimization(bMVO),binary bowerbird optimization(bSBO),binary hysteresis optimization(bHy),and binary hysteresis optimization(bHWO).The suggested method is superior 4532 CMC,2023,vol.74,no.2 and successful in handling the problem of feature selection,according to the results of the experiments. 展开更多
关键词 Metaheuristics dipper throated optimization grey wolf optimization binary optimizer feature selection
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Comparison of postoperative sore throat following laryngoscopy conducted by Miller and Macintosh laryngoscope blades 被引量:1
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作者 Khosro Barkhordari Farhad Etezadi +1 位作者 Reza Shariat Moharari Mohammad Reza Khajavi 《Health》 2011年第10期623-625,共3页
BACKGROUND: Post operative sore throat (PST) is one of the most common complaints after tracheal intubation. In this study we compared the effects of curved and straight laryngoscope blades on severity and incidence o... BACKGROUND: Post operative sore throat (PST) is one of the most common complaints after tracheal intubation. In this study we compared the effects of curved and straight laryngoscope blades on severity and incidence of PST. METHOD: In this prospective randomized clinical trial we evaluated incidence and severity of PST in 147 ASA physical status I–II, aged 18 – 62 y (group Miller, n = 71), (group Macintosh, n = 76) following intubation with Miller and Macintosh laryngoscope blades by using Visual Analog Scale (VAS). RESULTS: The overall incidence of PST in our study was 35.4% (Macintosh group = 39.5% and in Miller group = 31% and P = 0.829). The incidence of PST was not statistically different between two kinds of laryngoscope blades and the mean rank of pain score was not statistically different in recovery room and up to 48 hours after surgery. CONCLUSIONS: Our study showed these types of laryngoscope blade had not association with incidence and severity of PST. . 展开更多
关键词 Post Operative SORE throat TRACHEAL Incubation LARYNGOSCOPE BLADES
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Thermoregulatory function and sexual dimorphism of the throat sack in Helmeted Guineafowl(Numida meleagris)across Africa 被引量:1
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作者 Johann H.Van Niekerk Rodrigo Megía-Palma Giovanni Forcina 《Avian Research》 SCIE CSCD 2022年第3期239-248,共10页
The responses of ground-dwelling birds to heat and cold stress encompass a variety of behavioural,physiological and even morphological mechanisms.However,the role of glabrous skin in this respect has been marginally a... The responses of ground-dwelling birds to heat and cold stress encompass a variety of behavioural,physiological and even morphological mechanisms.However,the role of glabrous skin in this respect has been marginally addressed so far.The Helmeted Guineafowl(Numida meleagris)is a landfowl distributed across Sub-Saharan Africa with eight traditionally recognised extant subspecies.Among the most prominent morphological traits underlying intraspecific variability are size and pigmentation of the bare throat skin(or sack),which might be related to the different habitats and environmental conditions across its wide range.In order to explore the Helmeted Guineafowl range-wide sack variation and pigmentation in relation to thermoregulation and sexual signalling,we collected morphometric and environmental information for N.m.coronata integrating field data with the inspection of photographic material encompassing seven subspecies and environmental information from their habitats.Field data evidenced that sack size was significantly correlated with ambient temperature,thus pointing to a likely involvement of the throat sack in thermoregulation.When the pictorial data from all subspecies were pooled,sack size correlated negatively with biomass,rainfall and humidity,while a positive correlation was found with annual solar irradiation.Sack size correlated positively with monthly temperature variation among the bluethroated subspecies from southern Africa as opposed to the black-throated subspecies ranging north to Zambia and Mozambique.Still,in this latter group the sack was often larger during winter months,possibly to maximise solar radiation absorbance.Noteworthy,sack size was related to sex dimorphism in two subspecies.Sack morphology and colour in the Helmeted Guineafowl likely modulate body temperature by evaporative cooling or heating upon needs,but in some subspecies it is also seemingly related to sexual signalling.Additional studies are needed to fully understand the multifunctionality of this important morphological feature in this species. 展开更多
关键词 Evaporative cooling Helmeted guineafowl Sexual size dimorphism Sub-Saharan Africa THERMOREGULATION throat sack
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The influence of Laval nozzle throat size on supersonic molecular beam injection 被引量:1
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作者 Xinkui He Xianfu Feng +3 位作者 Mingmin Zhong Fujun Gou Shuiquan Deng Yong Zhao 《Journal of Modern Transportation》 2014年第2期118-121,共4页
In this study, finite element analysis (FEA) has been used to investigate the effects of different Laval nozzle throat sizes on supersonic molecular beam. The simulations indicate the Mach numbers of the molecular s... In this study, finite element analysis (FEA) has been used to investigate the effects of different Laval nozzle throat sizes on supersonic molecular beam. The simulations indicate the Mach numbers of the molecular stream peak at different positions along the center axis of the beam, which correspond to local minimums of the molecular densities. With the increase of the throat diameter, the first peak of the Mach number increases first and then decreases, while that of the molecular number density increases gradually. Moreover, both first peaks shift progressively away from the throat. At the last part, we discuss the possible applications of our FEA approach to solve some crucial problems met in modern transportations. 展开更多
关键词 Nuclear fusion Molecular beam injection Mach number Laval nozzle throat size
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Micro pore and throat characteristics and origin of tight sandstone reservoirs: A case study of the Triassic Chang 6 and Chang 8 members in Longdong area, Ordos Basin, NW China 被引量:2
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作者 LIU Hanlin YANG Youyun +5 位作者 WANG Fengqin DENG Xiuqin LIU Ye NAN Junxiang WANG Jin ZHANG Hongjie 《Petroleum Exploration and Development》 2018年第2期239-250,共12页
The microstructure differences of the Triassic Chang 6 and Chang 8 members tight reservoirs in the Longdong area of Ordos Basin were compared by means of cast thin sections, scanning electron microscope, X-ray diffrac... The microstructure differences of the Triassic Chang 6 and Chang 8 members tight reservoirs in the Longdong area of Ordos Basin were compared by means of cast thin sections, scanning electron microscope, X-ray diffraction, and constant rate mercury injection. Their pore evolution models were established, and the effects of main diagenesis on densification were examined. The throat is the main factor controlling the physical properties of the Chang 6 and Chang 8 members reservoirs: The lower the permeability, the smaller and the more concentrated the throat radius and the larger the proportion of the throats in the effective storage space. There are several obvious differences between Chang 6 and Chang 8 members:(1) with the increase of permeability, the contribution of the relative large throats to the permeability in the Chang 8 member reservoir is more than that in the Chang 6 member reservoir;(2) the control effect on pore-throat ratio of the nano-throats in the Chang 6 member reservoir is more significant. The sedimentary action determines the primary pore structure of the Chang 6 and Chang 8 members sand bodies, and the diagenesis is the main factor controlling the densification of the reservoirs. Because of the difference in rock fabrics and the chlorite content of Chang 6 and Chang 8, the strong compaction resulted in less porosity reduction(17%) of the Chang 81 reservoir with larger buried depth and larger ground temperature than the Chang 63 reservoir(19%). The siliceous, calcareous and clay minerals cement filling the pores and blocking the pore throat, which is the key factor causing the big differences between the reservoir permeability of Chang 6 and Chang 8 members. 展开更多
关键词 ORDOS Basin TRIASSIC Yanchang Formation tight SANDSTONE reservoir constant-speed mercury intrusion micro pore and throat structure
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Prof.Sheng Canruo's Experience in Acupuncture Treatment of Throat Diseases with Yan Si Xue 被引量:1
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作者 姚文龙 王新中 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2000年第2期122-125,共4页
Yan Si Xue(咽四穴)refer to four points in the throat summarized by Prof.Sheng Canruo in his long-year clinical experience based on the combination of TCM theory and the knowledge of modernmedical anatomy.By taking “Y... Yan Si Xue(咽四穴)refer to four points in the throat summarized by Prof.Sheng Canruo in his long-year clinical experience based on the combination of TCM theory and the knowledge of modernmedical anatomy.By taking “Yan Si Xue” as main points,and other differential adjunct points,Prof.Sheng has obtained satisfactory therapeutic results in treating various throat diseases such ashoarseness,paralysis of vocal cord,dysphonia after radiotherapy on throat tumor,vocal nodules,disorder of the glossopharyngeal nerve,hysteric aphasia,and acute or chronic laryngopharyngitis. 展开更多
关键词 Prof.Sheng Canruo’s Experience in Acupuncture Treatment of throat Diseases with Yan Si Xue
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Classification of microscopic pore-throats and the grading evaluation on shale oil reservoirs 被引量:2
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作者 LU Shuangfang LI Junqian +5 位作者 ZHANG Pengfei XUE Haitao WANG Guoli ZHANG Jun LIU Huimin LI Zheng 《Petroleum Exploration and Development》 2018年第3期452-460,共9页
On the basis of the characterization of microscopic pore-throats in shale oil reservoirs by high-pressure mercury intrusion technique, a grading evaluation standard of shale oil reservoirs and a lower limit for reserv... On the basis of the characterization of microscopic pore-throats in shale oil reservoirs by high-pressure mercury intrusion technique, a grading evaluation standard of shale oil reservoirs and a lower limit for reservoir formation were established. Simultaneously, a new method for the classification of shale oil flow units based on logging data was established. A new classification scheme for shale oil reservoirs was proposed according to the inflection points and fractal features of mercury injection curves: microscopic pore-throats(less than 25 nm), small pore-throats(25-100 nm), medium pore-throats(100-1 000 nm) and big pore-throats(greater than 1 000 nm). Correspondingly, the shale reservoirs are divided into four classes, I, II, III and IV according to the number of microscopic pores they contain, and the average pore-throat radii corresponding to the dividing points are 150 nm, 70 nm and 10 nm respectively. By using the correlation between permeability and pore-throat radius, the permeability thresholds for the reservoir classification are determined at 1.00× 10^(-3) μm^2, 0.40×10^(-3) μm^2 and 0.05×10^(-3) μm^2 respectively. By using the exponential relationship between porosity and permeability of the same hydrodynamic flow unit, a new method was set up to evaluate the reservoir flow belt index and to identify shale oil flow units with logging data. The application in the Dongying sag shows that the standard proposed is suitable for grading evaluation of shale oil reservoirs. 展开更多
关键词 SHALE oil MICROSCOPIC pore-throat high pressure mercury injection lower limit of reservoir formation GRADING EVALUATION Bohai Bay Basin Dongying SAG
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Comparison of Postoperative Throat and Neck Complaints after the Use of the i-Gel versus the Traditional Laryngeal Mask 被引量:1
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作者 Ana Sofia Del Castillo Sardi Marion Britto Janeth Rangel 《Open Journal of Anesthesiology》 2013年第4期233-236,共4页
Introduction: One of the most important jobs of an anesthesiology is to preserve an adequate gaseous exchange. With the coming in the 80’s of the laryngeal mask airway, a less invasive technique was introduced for th... Introduction: One of the most important jobs of an anesthesiology is to preserve an adequate gaseous exchange. With the coming in the 80’s of the laryngeal mask airway, a less invasive technique was introduced for this end. There are a lot of variants of these supraglotic issues, being the i-gel a no inflate mask;witch principle is to provide a perilaryngel stamp that reduced the incidence of sore throat, cervical pain compared with the traditional laryngeal mask. Method: A group of 121 ASA I-II patients with general anesthesia administration, where divided in two groups, one of 60 patients where a traditional laryngeal mask airway was used, and a second group of 61 patients where an i-gel mask was used. In both groups the presence of postoperative sore throat, cervical pain and dysphonia;number of attempts and pressure in the airway tract was measured. Results: The group of patients where the i-gel was used present lower incidence of sore throat (11% vs 27%) and cervical pain (3% vs 9%) and lower values of pressure on the airway tract compared with the group in which the conventional laryngeal mask was used. On the other hand there was no difference in the presence of dysphonia, trauma or number of attempts used to insert the mask. Conclusions: The i-gel larygeal mask demonstrated to be a safe issue, with low incidence of morbidity to administrated general anesthesia. 展开更多
关键词 i-Gel Laryngeal Mask Cervical Pain Sore throat
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A novel contour design technique of super/hypersonic nozzle diverging section with sharing throat
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作者 郭善广 王振国 +1 位作者 赵玉新 柳军 《Journal of Central South University》 SCIE EI CAS 2014年第7期2766-2771,共6页
A straightforward technique has been developed to quickly determine the wall contour of super/hypersonic nozzles working at multiply Mach number which share a common throat section.Mach number distribution along the c... A straightforward technique has been developed to quickly determine the wall contour of super/hypersonic nozzles working at multiply Mach number which share a common throat section.Mach number distribution along the centerline of the nozzle is specified in advance and divided into two sections,both of which are described by the b-spline function.The first section is shared by different exit Mach number nozzles.The nozzle contour is determined by the method of characteristics plus boundary layer correction.An example of this design method is employed to illustrate the technique with a computational fluid dynamics calculation.The simulation results indicate that desired Mach numbers are obtained at the nozzle exit,and the good flow quality is attained for different nozzles within δMa/Ma<±0.56% in the flow core region.This technique improves the design precision of the converging-diverging nozzle,cancels waves completely,and achieves nozzles with multiple Mach number exiting which share a common throat section. 展开更多
关键词 supersonic flow nozzle design throat section multiple Mach number method of characteristics
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Transfer Learning for Chest X-rays Diagnosis Using Dipper Throated Algorithm
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作者 Hussah Nasser AlEisa El-Sayed M.El-kenawy +3 位作者 Amel Ali Alhussan Mohamed Saber Abdelaziz A.Abdelhamid Doaa Sami Khafaga 《Computers, Materials & Continua》 SCIE EI 2022年第11期2371-2387,共17页
Most children and elderly people worldwide die from pneumonia,which is a contagious illness that causes lung ulcers.For diagnosing pneumonia from chest X-ray images,many deep learning models have been put forth.The go... Most children and elderly people worldwide die from pneumonia,which is a contagious illness that causes lung ulcers.For diagnosing pneumonia from chest X-ray images,many deep learning models have been put forth.The goal of this research is to develop an effective and strong approach for detecting and categorizing pneumonia cases.By varying the deep learning approach,three pre-trained models,GoogLeNet,ResNet18,and DenseNet121,are employed in this research to extract the main features of pneumonia and normal cases.In addition,the binary dipper throated optimization(DTO)algorithm is utilized to select the most significant features,which are then fed to the K-nearest neighbor(KNN)classifier for getting the final classification decision.To guarantee the best performance of KNN,its main parameter(K)is optimized using the continuous DTO algorithm.To test the proposed approach,six evaluation metrics were employed namely,positive and negative predictive values,accuracy,specificity,sensitivity,and F1-score.Moreover,the proposed approach is compared with other traditional approaches,and the findings confirmed the superiority of the proposed approach in terms of all the evaluation metrics.The minimum accuracy achieved by the proposed approach is(98.5%),and the maximum accuracy is(99.8%)when different test cases are included in the evaluation experiments. 展开更多
关键词 METAHEURISTIC PNEUMONIA dipper throated optimization KNN
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Adaptive Dynamic Dipper Throated Optimization for Feature Selection in Medical Data
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作者 Ghada Atteia El-Sayed M.El-kenawy +7 位作者 Nagwan Abdel Samee Mona M.Jamjoom Abdelhameed Ibrahim Abdelaziz A.Abdelhamid Ahmad Taher Azar Nima Khodadadi Reham A.Ghanem Mahmoud Y.Shams 《Computers, Materials & Continua》 SCIE EI 2023年第4期1883-1900,共18页
The rapid population growth results in a crucial problem in the early detection of diseases inmedical research.Among all the cancers unveiled,breast cancer is considered the second most severe cancer.Consequently,an e... The rapid population growth results in a crucial problem in the early detection of diseases inmedical research.Among all the cancers unveiled,breast cancer is considered the second most severe cancer.Consequently,an exponential rising in death cases incurred by breast cancer is expected due to the rapid population growth and the lack of resources required for performing medical diagnoses.Utilizing recent advances in machine learning could help medical staff in diagnosing diseases as they offer effective,reliable,and rapid responses,which could help in decreasing the death risk.In this paper,we propose a new algorithm for feature selection based on a hybrid between powerful and recently emerged optimizers,namely,guided whale and dipper throated optimizers.The proposed algorithm is evaluated using four publicly available breast cancer datasets.The evaluation results show the effectiveness of the proposed approach from the accuracy and speed perspectives.To prove the superiority of the proposed algorithm,a set of competing feature selection algorithms were incorporated into the conducted experiments.In addition,a group of statistical analysis experiments was conducted to emphasize the superiority and stability of the proposed algorithm.The best-achieved breast cancer prediction average accuracy based on the proposed algorithm is 99.453%.This result is achieved in an average time of 3.6725 s,the best result among all the competing approaches utilized in the experiments. 展开更多
关键词 Medical dataset breast cancer guided whale optimizer dipper throated optimizer feature selection META-HEURISTICS
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Dipper Throated Optimization for Detecting Black-Hole Attacks inMANETs
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作者 Reem Alkanhel El-Sayed M.El-kenawy +3 位作者 Abdelaziz A.Abdelhamid Abdelhameed Ibrahim Mostafa Abotaleb Doaa Sami Khafaga 《Computers, Materials & Continua》 SCIE EI 2023年第1期1905-1921,共17页
In terms of security and privacy,mobile ad-hoc network(MANET)continues to be in demand for additional debate and development.As more MANET applications become data-oriented,implementing a secure and reliable data tran... In terms of security and privacy,mobile ad-hoc network(MANET)continues to be in demand for additional debate and development.As more MANET applications become data-oriented,implementing a secure and reliable data transfer protocol becomes a major concern in the architecture.However,MANET’s lack of infrastructure,unpredictable topology,and restricted resources,as well as the lack of a previously permitted trust relationship among connected nodes,contribute to the attack detection burden.A novel detection approach is presented in this paper to classify passive and active black-hole attacks.The proposed approach is based on the dipper throated optimization(DTO)algorithm,which presents a plausible path out of multiple paths for statistics transmission to boost MANETs’quality of service.A group of selected packet features will then be weighed by the DTO-based multi-layer perceptron(DTO-MLP),and these features are collected from nodes using the Low Energy Adaptive Clustering Hierarchical(LEACH)clustering technique.MLP is a powerful classifier and the DTO weight optimization method has a significant impact on improving the classification process by strengthening the weights of key features while suppressing the weights ofminor features.This hybridmethod is primarily designed to combat active black-hole assaults.Using the LEACH clustering phase,however,can also detect passive black-hole attacks.The effect of mobility variation on detection error and routing overhead is explored and evaluated using the suggested approach.For diverse mobility situations,the results demonstrate up to 97%detection accuracy and faster execution time.Furthermore,the suggested approach uses an adjustable threshold value to make a correct conclusion regarding whether a node is malicious or benign. 展开更多
关键词 Black-hole attack mobile ad-hoc network OPTIMIZATION dipper throated optimization
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Hybrid Grey Wolf and Dipper Throated Optimization in Network Intrusion Detection Systems
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作者 Reem Alkanhel Doaa Sami Khafaga +5 位作者 El-Sayed M.El-kenawy Abdelaziz A.Abdelhamid Abdelhameed Ibrahim Rashid Amin Mostafa Abotaleb B.M.El-den 《Computers, Materials & Continua》 SCIE EI 2023年第2期2695-2709,共15页
The Internet of Things(IoT)is a modern approach that enables connection with a wide variety of devices remotely.Due to the resource constraints and open nature of IoT nodes,the routing protocol for low power and lossy... The Internet of Things(IoT)is a modern approach that enables connection with a wide variety of devices remotely.Due to the resource constraints and open nature of IoT nodes,the routing protocol for low power and lossy(RPL)networks may be vulnerable to several routing attacks.That’s why a network intrusion detection system(NIDS)is needed to guard against routing assaults on RPL-based IoT networks.The imbalance between the false and valid attacks in the training set degrades the performance of machine learning employed to detect network attacks.Therefore,we propose in this paper a novel approach to balance the dataset classes based on metaheuristic optimization applied to locality-sensitive hashing and synthetic minority oversampling technique(LSH-SMOTE).The proposed optimization approach is based on a new hybrid between the grey wolf and dipper throated optimization algorithms.To prove the effectiveness of the proposed approach,a set of experiments were conducted to evaluate the performance of NIDS for three cases,namely,detection without dataset balancing,detection with SMOTE balancing,and detection with the proposed optimized LSHSOMTE balancing.Experimental results showed that the proposed approach outperforms the other approaches and could boost the detection accuracy.In addition,a statistical analysis is performed to study the significance and stability of the proposed approach.The conducted experiments include seven different types of attack cases in the RPL-NIDS17 dataset.Based on the 2696 CMC,2023,vol.74,no.2 proposed approach,the achieved accuracy is(98.1%),sensitivity is(97.8%),and specificity is(98.8%). 展开更多
关键词 Metaheuristics grey wolf optimization dipper throated optimization dataset balancing locality sensitive hashing SMOTE
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