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Efficacy of fexuprazan compared with rebamipide in Korean patients with gastritis:A matching-adjusted indirect comparison
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作者 Gwang Ha Kim Hang Lak Lee 《World Journal of Clinical Cases》 SCIE 2024年第19期3890-3897,共8页
BACKGROUND Gastritis is one of the most frequently diagnosed diseases requiring medical treatment in South Korea.Fexuprazan,a novel potassium-competitive acid blocker,has been approved for treating gastritis and erosi... BACKGROUND Gastritis is one of the most frequently diagnosed diseases requiring medical treatment in South Korea.Fexuprazan,a novel potassium-competitive acid blocker,has been approved for treating gastritis and erosive esophagitis.Meanwhile,rebamipide is the most commonly used mucoprotective agent for acute and chronic gastritis in real-world settings in South Korea.However,there have been no studies comparing the efficacy of these two drugs yet.AIM To compare the efficacy of fexuprazan with that of rebamipide for acute and chronic gastritis.METHODS This was a matching-adjusted indirect comparison.Individual patient data from a phase III study of fexuprazan(10 mg BID)were compared with cumulative data from two matching studies of rebamipide(100 mg TID).Erosion improvement and healing rates were compared between two weeks of fexurapan,two weeks of rebamipide,and four weeks of rebamipide.The two main outcome variables were presented as percentages,and the risk differences(RD)and 95%confidence intervals(CI)were calculated for the relative treatment effects.RESULTS In the primary analysis,the erosion improvement and healing rates after a twoweek treatment with fexuprazan were 64.5%and 53.2%,respectively,while a twoweek treatment with rebamipide resulted in erosion improvement and healing rates of 43.6%(RD:21.0%;95%CI:9.6-32.3;P<0.01)and 35.6%(RD:17.6%;95%CI:6.1-29.2;P=0.003),respectively.In the additional analysis,the erosion improvement and healing rates for the two-week fexuprazan treatment(64.2%and 51.2%,respectively)were similar to those obtained during a four-week treatment with rebamipide(60.6%;RD:3.6%;95%CI:-9.8,17.0;P=0.600 and 53.5%;RD:-2.3%;95%CI:-16.1,11.5;P=0.744,respectively).CONCLUSION The two-week fexuprazan treatment was superior to the two-week rebamipide treatment and similar to the fourweek rebamipide treatment for patients with gastritis. 展开更多
关键词 GASTRITIS Erosive gastritis Fexuprazan REBAMIPIDE Matching-adjusted indirect comparison indirect treatment comparison
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Indirect neutron radiography experiment on dummy nuclear fuel rods for pressurized water reactors at CMRR
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作者 Yong Sun Qi-Biao Wang +11 位作者 Peng-Cheng Li Ming Xia Bin Liu He-Yong Huo Wei Yin Yang Wu Sheng Wang Chao Cao Xin Yang Run-Dong Li Hang Li Bin Tang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第11期13-27,共15页
Nuclear energy is a vital source of clean energy that will continue to play an essential role in global energy production for future generations.Nuclear fuel rods are core components of nuclear power plants,and their ... Nuclear energy is a vital source of clean energy that will continue to play an essential role in global energy production for future generations.Nuclear fuel rods are core components of nuclear power plants,and their safe utilization is paramount.Due to its inherent high radioactivity,indirect neutron radiography(INR)is currently the only viable technology for irradiated nuclear fuel rods in the field of energy production.This study explores the experimental technique of indirect neutron computed tomography(INCT)for radioactive samples.This project includes the development of indium and dysprosium conversion screens of different thicknesses and conducts resolution tests to assess their performance.Moreover,pressurized water reactor(PWR)dummy nuclear fuel rods have been fabricated by self-developing substitute materials for cores and outsourcing of mechanical processing.Experimental research on the INR is performed using the developed dummy nuclear fuel rods.The sparse reconstruction technique is used to reconstruct the INR results of 120 pairs of dummy nuclear fuel rods at different angles,achieving a resolution of 0.8 mm for defect detection using INCT. 展开更多
关键词 Conversion screen DYSPROSIUM indirect neutron computed tomography Dummy nuclear fuel rods
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Optimizing PID controller parameters for robust automatic voltage regulator system through indirect design approach-2
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作者 Mohd Zaidi Mohd Tumari Mohd Ashraf Ahmad +1 位作者 Mohd Riduwan Ghazali Mohd Helmi Suid 《Global Energy Interconnection》 EI CSCD 2024年第5期682-696,共15页
Automatic voltage regulators(AVR)are designed to manipulate a synchronous generator’s voltage level automatically.Proportional integral derivative(PID)controllers are typically used in AVR systems to regulate voltage... Automatic voltage regulators(AVR)are designed to manipulate a synchronous generator’s voltage level automatically.Proportional integral derivative(PID)controllers are typically used in AVR systems to regulate voltage.Although advanced PID tuning methods have been proposed,the actual voltage response differs from the theoretical predictions due to modeling errors and system uncertainties.This requires continuous fine tuning of the PID parameters.However,manual adjustment of these parameters can compromise the stability and robustness of the AVR system.This study focuses on the online self-tuning of PID controllers called indirect design approach-2(IDA-2)in AVR systems while preserving robustness.In particular,we indirectly tune the PID controller by shifting the frequency response.The new PID parameters depend on the frequency-shifting constant and the previously optimized PID parameters.Adjusting the frequency-shifting constant modifies all the PID parameters simultaneously,thereby improving the control performance and robustness.We evaluate the robustness of the proposed online PID tuning method by comparing the gain margins(GMs)and phase margins(PMs)with previously optimized PID parameters during parameter uncertainties.The proposed method is further evaluated in terms of disturbance rejection,measurement noise,and frequency response analysis during parameter uncertainty calculations against existing methods.Simulations show that the proposed method significantly improves the robustness of the controller in the AVR system.In summary,online self-tuning enables automated PID parameter adjustment in an AVR system,while maintaining stability and robustness. 展开更多
关键词 PID controller tuning AVR system indirect design approach(IDA) Frequency-shifting Robust control
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Behavior of exciton in direct−indirect band gap Al_(x)Ga_(1−x)As crystal lattice quantum wells
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作者 Yong Sun Wei Zhang +10 位作者 Shuang Han Ran An Xin-Sheng Tang Xin-Lei Yu Xiu-Juan Miao Xin-Jun Ma Xianglian Pei-Fang Li Cui-Lan Zhao Zhao-Hua Ding Jing-Lin Xiao 《Journal of Semiconductors》 EI CAS CSCD 2024年第3期64-70,共7页
Excitons have significant impacts on the properties of semiconductors.They exhibit significantly different properties when a direct semiconductor turns in to an indirect one by doping.Huybrecht variational method is a... Excitons have significant impacts on the properties of semiconductors.They exhibit significantly different properties when a direct semiconductor turns in to an indirect one by doping.Huybrecht variational method is also found to influence the study of exciton ground state energy and ground state binding energy in Al_(x)Ga_(1−x)As semiconductor spherical quantum dots.The Al_(x)Ga_(1−x)As is considered to be a direct semiconductor at AI concentration below 0.45,and an indirect one at the concentration above 0.45.With regards to the former,the ground state binding energy increases and decreases with AI concentration and eigenfrequency,respectively;however,while the ground state energy increases with AI concentration,it is marginally influenced by eigenfrequency.On the other hand,considering the latter,while the ground state binding energy increases with AI concentration,it decreases with eigenfrequency;nevertheless,the ground state energy increases both with AI concentration and eigenfrequency.Hence,for the better practical performance of the semiconductors,the properties of the excitons are suggested to vary by adjusting AI concentration and eigenfrequency. 展开更多
关键词 exciton effects aluminum gallium arsenide crystal direct band gap semiconductor indirect band gap semiconductor
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Omental fibroma combined with right indirect inguinal hernia masquerades as a scrotal tumor: A case report
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作者 Ping Zhou Chan-Hui Jin +6 位作者 Ying Shi Guo-Qing Ma Wen-Hao Wu Yu Wang Kun Cai Wu-Feng Fan Tian-Bao Wang 《World Journal of Clinical Cases》 SCIE 2024年第5期988-994,共7页
BACKGROUND The most common causes of scrotal enlargement in patients include primary tumor of the scrotum,inflammation,hydrocele of the tunica vaginalis,and indirect inguinal hernia;scrotal enlargement caused by exter... BACKGROUND The most common causes of scrotal enlargement in patients include primary tumor of the scrotum,inflammation,hydrocele of the tunica vaginalis,and indirect inguinal hernia;scrotal enlargement caused by external tumors of the scrotum is rare.The patient had both a greater omentum tumor and an inguinal hernia,and the tumor protruded into the scrotum through the hernia sac,which is even rarer.Moreover,omental tumors are mostly metastatic,and primary omental fibroma is rare.CASE SUMMARY Here,we report a rare case of a 25-year-old young man with scrotal enlargement and pain for 3 months.Preoperative examination and multidisciplinary discu-ssions considered intra-abdominal tumor displacement and inguinal hernia,and intraoperative exploration confirmed that the greater omentum tumor protruded into the scrotum.Therefore,tumor resection and tension-free inguinal hernia repair were performed.The final diagnosis was benign fibroma of the greater omentum accompanied by an indirect inguinal hernia.CONCLUSION This unusual presentation of a common inguinal hernia disease illustrates the necessity of performing detailed history taking,physical examination,and imaging before surgery. 展开更多
关键词 HERNIA indirect inguinal hernia FIBROMA Omental tumor Scrotal tumor Greater omentum Case report
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Fracture propagation and evolution law of indirect fracturing in the roof of broken soft coal seams
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作者 Haifeng Zhao Pengyue Li +1 位作者 Xuejiao Li Wenjie Yao 《International Journal of Coal Science & Technology》 EI CAS CSCD 2024年第1期78-102,共25页
Indirect fracturing in the roof of broken soft coal seams has been demonstrated to be a feasible technology.In this work,the No.5 coal seam in the Hancheng block was taken as the research object.Based on the findings ... Indirect fracturing in the roof of broken soft coal seams has been demonstrated to be a feasible technology.In this work,the No.5 coal seam in the Hancheng block was taken as the research object.Based on the findings of true triaxial hydraulic fracturing experiments and field pilot under this technology and the cohesive element method,a 3D numerical model of indirect fracturing in the roof of broken soft coal seams was established,the fracture morphology propagation and evolution law under different conditions was investigated,and analysis of main controlling factors of fracture parameters was conducted with the combination weight method,which was based on grey incidence,analytic hierarchy process and entropy weight method.The results show that“士”-shaped fractures,T-shaped fractures,cross fractures,H-shaped fractures,and“干”-shaped fractures dominated by horizontal fractures were formed.Different parameter combinations can form different fracture morphologies.When the coal seam permeability is lower and the minimum horizontal principal stress difference between layers and fracturing fluid injection rate are both larger,it tends to form“士”-shaped fractures.When the coal seam permeability and minimum horizontal principal stress between layers and perforation position are moderate,cross fractures are easily generated.Different fracture parameters have different main controlling factors.Engineering factors of perforation location,fracturing fluid injection rate and viscosity are the dominant factors of hydraulic fracture shape parameters.This study can provide a reference for the design of indirect fracturing in the roof of broken soft coal seams. 展开更多
关键词 indirect fracturing Roof of coal seam Fracture propagation and evolution Coalbed methane Cohesive element method Combination weight method
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Experimental Study and Thermal Modelling of Cocoa Shell Convective Drying in an Indirect Solar Dryer
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作者 Siaka Touré Adjo Christelle Ogo Modibo Sidibé 《Modeling and Numerical Simulation of Material Science》 2024年第2期69-78,共10页
The concern of the present work is the convective drying of empty cocoa shells in an indirect solar dryer. Some drying experiments, using one sample, were carried out. During the experiments, the sample is introduced ... The concern of the present work is the convective drying of empty cocoa shells in an indirect solar dryer. Some drying experiments, using one sample, were carried out. During the experiments, the sample is introduced in the drying chamber. Then at steady time intervals, the sample is withdrawn from the drying chamber, for a rapid weighing. After each weighing, the sample is reintroduced in the dryer. At each time interval, the ambient temperature of the drying chamber and its relative humidity γ are measured by a thermo-hygrometer. From the experimental data, a theoretical determination of the moisture evaporated from the product was performed and a good agreement was found between the theoretical and experimental values, confirmed by the value of the RMSE. Those calculations used the constants in the Nusselt number found in literature. Then those constants were evaluated again, to get new values more suitable with the experimental data. The dimensionless numbers of Nusselt, Grashof and Prandtl were calculated. That allowed the calculation of the average value of the Nusselt number. The average convective heat transfer coefficient was determined. 展开更多
关键词 Shells of Cocoa Pods indirect Solar Dryer Moisture Evaporated Constants of the Nusselt Number Convective Heat Transfer Coefficient
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Factors that influence the results of indirect decompression employing oblique lumbar interbody fusion
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作者 Andrey E Bokov Svetlana Y Kalinina +2 位作者 Mingiyan I Khaltyrov Alexandr P Saifullin Anatoliy A Bulkin 《World Journal of Orthopedics》 2024年第8期734-743,共10页
BACKGROUND Indirect decompression is one of the potential benefits of anterior reconstruction in patients with spinal stenosis.On the other hand,the reported rate of revision surgery after indirect decompression highl... BACKGROUND Indirect decompression is one of the potential benefits of anterior reconstruction in patients with spinal stenosis.On the other hand,the reported rate of revision surgery after indirect decompression highlights the necessity of working out prediction models for the radiographic results of indirect decompression with assessing their clinical relevance.AIM To assess factors that influence radiographic and clinical results of the indirect decompression in patients with stenosis of the lumbar spine.METHODS This study is a single-center cross-sectional evaluation of 80 consecutive patients(17 males and 63 females)with lumbar spinal stenosis combined with the instability of the lumbar spinal segment.Patients underwent single level or bisegmental spinal instrumentation employing oblique lumbar interbody fusion(OLIF)with percutaneous pedicle screw fixation.Radiographic results of the indirect decompression were assessed using computerized tomography,while MacNab scale was used to assess clinical results.RESULTS After indirect decompression employing anterior reconstruction using OLIF,the statistically significant increase in the disc space height,vertebral canal square,right and left lateral canal depth were detected(Р<0.0001).The median(M)relative vertebral canal square increase came toМ=24.5%with 25%-75%quartile border(16.3%;33.3%)if indirect decompression was achieved by restoration of the segment height.In patients with the reduction of the upper vertebrae slip,the median of the relative increase in vertebral canal square accounted for 49.5%with 25%-75%quartile border(2.35;99.75).Six out of 80 patients(7.5%)presented with unsatisfactory results because of residual nerve root compression.The critical values for lateral recess depth and vertebral canal square that were associated with indirect decompression failure were 3 mm and 80 mm2 respectively.CONCLUSION Indirect decompression employing anterior reconstruction is achieved by the increase in disc height along the posterior boarder and reduction of the slipped vertebrae in patients with degenerative spondylolisthesis.Vertebral canal square below 80 mm2 and lateral recess depth less than 3 mm are associated with indirect decompression failures that require direct microsurgical decompression. 展开更多
关键词 indirect decompression Anterior reconstruction Central lumbar spinal stenosis Degenerative spondylolisthesis Lateral recess stenosis Spinal instability Oblique lateral interbody fusion
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Analysis of Standards and Effects of Police Indirect Court of Human Rights——Taking“Akbay and Others v.Germany”as an Example
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作者 刘梅湘 侯慧茹 CHEN Feng 《The Journal of Human Rights》 2024年第1期202-230,共29页
The European Court of Human Rights(ECtHR)has ruled that illegal indirect entrapment must meet three criteria simultaneously.This mixed standard requires that the previous direct entrapment violates the“essentially pa... The European Court of Human Rights(ECtHR)has ruled that illegal indirect entrapment must meet three criteria simultaneously.This mixed standard requires that the previous direct entrapment violates the“essentially passive,”subsequent indirect entrapment satisfies the“reasonable foreseeability,”and police entrapment of secondary defendants to commit crimes is considered“decisive.”The legal consequences of indirect entrapment are distinguished between general indirect entrapment and illegal indirect entrapment.The basic position of the ECtHR on the consequences of illegal indirect entrapment has shifted from supporting mitigating penalties to recognizing procedural dismissal,and general indirect entrapment is considered a mitigating factor in sentencing.Against the backdrop of increasing internationalization of criminal justice standards,the above criteria and positions have strong implications for the improvement of relevant rules in China. 展开更多
关键词 indirect entrapment direct entrapment standard of legitimacy legal consequence
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Indirect Electroanalysis of 3-Methyl-4-Nitrophenol in Water Using Carbon Fiber Microelectrode Modified with Nickel Tetrasulfonated Phthalocyanine Complex
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作者 Yibor Fabrice Roland Bako Serge Foukmeniok Mbokou +2 位作者 Boukaré Kaboré Issa Tapsoba Maxime Pontié 《Materials Sciences and Applications》 2024年第2期25-35,共11页
Electrochemical detection of 3-methyl-4-nitrophenol (MNP) in direct phenol oxidation occurs at high potentials and generally leads to progressive passivation of the electrochemical sensor. This study describes the use... Electrochemical detection of 3-methyl-4-nitrophenol (MNP) in direct phenol oxidation occurs at high potentials and generally leads to progressive passivation of the electrochemical sensor. This study describes the use of a carbon fiber microelectrode modified with a tetrasulfonated nickel phthalocyanine complex for the detection of MNP at a lower potential than that of direct phenol oxidation. The MNP voltammogram showed the presence of an anodic peak at -0.11 V vs SCE, corresponding to the oxidation of the hydroxylamine group generated after the reduction of the nitro group. The effect of buffer pH on the peak current and SWV parameters such as frequency, scan increment, and pulse amplitude were studied and optimized to have better electrochemical response of the proposed sensor. With these optimal parameters, the calibration curve shows that the peak current varied linearly as a function of MNP concentration, leading to a limit of detection (LoD) of 1.1 μg/L. These results show an appreciable sensitivity of the sensor for detecting the MNP at relatively low potentials, making it possible to avoid passivation phenomena. 展开更多
关键词 3-Methyl-4-Nitrophenol Carbon Fiber Microelectrode Nickel Tetrasulfonated Phthalocyanine indirect Electroanalysis Square Wave Voltammetry
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Indirect tension test of epoxy asphalt mixtureusing microstructural finite-element model 被引量:8
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作者 王江洋 钱振东 《Journal of Southeast University(English Edition)》 EI CAS 2011年第1期65-69,共5页
A finite-element model of the thermosetting epoxy asphalt mixture(EAM) microstructure is developed to simulate the indirect tension test(IDT).Image techniques are used to capture the EAM microstructure which is di... A finite-element model of the thermosetting epoxy asphalt mixture(EAM) microstructure is developed to simulate the indirect tension test(IDT).Image techniques are used to capture the EAM microstructure which is divided into two phases:aggregates and mastic.A viscoelastic constitutive relationship,which is obtained from the results of a creep test,is used to represent the mastic phase at intermittent temperatures.Model simulation results of the stiffness modulus in IDT compare favorably with experimental data.Different loading directions and velocities are employed in order to account for their influence on the modulus and the localized stress of the microstructure model.It is pointed out that the modulus is not consistent when the loading direction changes since the heterogeneous distribution of the mixture internal structure,and the loading velocity affects the localized stress as a result of the viscoelasticity of the mastic.The study results can provide a theoretical basis for the finite-element method,which can be extended to the numerical simulations of asphalt mixture micromechanical behavior. 展开更多
关键词 MICROSTRUCTURE epoxy asphalt mixture image techniques finite-element model indirect tension test
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Design calculation of porous ceramics tube type dew point indirect evaporative cooler 被引量:1
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作者 毛秀明 黄翔 文力 《Journal of Southeast University(English Edition)》 EI CAS 2010年第2期205-208,共4页
To improve the wall surface hydrophilicity of a tube type indirect evaporative cooler,a new method adopting porous ceramics is proposed.This method realizes the combination of porous ceramics and the evaporative cooli... To improve the wall surface hydrophilicity of a tube type indirect evaporative cooler,a new method adopting porous ceramics is proposed.This method realizes the combination of porous ceramics and the evaporative cooling technique.The design calculation of the porous ceramics tube type dew point indirect evaporative cooler are carried out from such aspects as the volumes and status parameters of the primary and secondary air,the cooler structure,the heat transfer of the solid porous ceramic tubes and the resistance of the cooler.The calculation results show that the design is reasonable.Finally,based on the design calculation,the porous ceramics tube type dew point indirect evaporative cooler is successfully manufactured. 展开更多
关键词 tube type indirect evaporative cooler dew point porous ceramics design calculation
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Capillary Zone Electrophoresis of Native Amino Acids with Indirect Ultraviolet Detection
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作者 王洪 顾峻岭 +2 位作者 傅若农 胡汉芳 丁天惠 《Journal of Beijing Institute of Technology》 EI CAS 1998年第1期43-48,共6页
Aim To strdy the separation of native amino acids using capillary zone electro- pboresis (CZE) with indirect ultraviolet detecition. Methods 13 native amino acids were sepa- rated by capillary electrophoresis with ind... Aim To strdy the separation of native amino acids using capillary zone electro- pboresis (CZE) with indirect ultraviolet detecition. Methods 13 native amino acids were sepa- rated by capillary electrophoresis with indirect detection . The experiments were carried out with homemade CE apparatus under the following operating conditior conditions: a fused-silica capillary col- umn of 50.0cm effect length and of 75m i.d. was used. 7 organic acids were used as BGAE, and a positive potential of separation in CZE with indirect detection. After optimizing for l3 native amino acids were established. Conclusion The choice of BGAe is an important factor influencing the efficiency of separation in CZE with indiect detection .After optimizing the separation conditions a baseline separation for 13 native amino acids is obtained. 展开更多
关键词 CZE indirect UV detection native amino acid
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Indirectness and Politeness in English Requests
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作者 周伟 《海外英语》 2014年第11X期269-270,共2页
Foreign language teachers may have long observed learners' grammatically correct, yet situationally inappropriate verbal communication. To make sure they conduct speech acts appropriately, language learners should... Foreign language teachers may have long observed learners' grammatically correct, yet situationally inappropriate verbal communication. To make sure they conduct speech acts appropriately, language learners should possess communicative skills and pragmatic competence. This paper addresses how to raise learners' pragmatic awareness through making requests in English.By exploring the verbal indirectness and politeness of requests, the paper aims to facilitate learners' ability to make socially appropriate utterances. 展开更多
关键词 indirectNESS POLITENESS SPEECH ACTS REQUESTS Engli
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Application of Nominal Indirect Anaphora in English Teaching and Learning
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作者 张杰 《快乐阅读(开心辞典)(上)》 2011年第26期49-50,共2页
This paper deals with the application of nominal indirect anaphora to unveil the essence of nominal indirect anaphora and disclose the magic power of cohesion and coherence inside it from the angle of cognitive lingui... This paper deals with the application of nominal indirect anaphora to unveil the essence of nominal indirect anaphora and disclose the magic power of cohesion and coherence inside it from the angle of cognitive linguistics.Thus we can apply the resolution mechanism for English teaching and learning for English learners. 展开更多
关键词 NOMINAL indirect ANAPHORA RESOLUTION mechanism LANGUAGE TEACHING and LEARNING
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A Review of Indirect Speech Acts in Speech Act Theory
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作者 张焕芹 《海外英语》 2018年第11期234-235,共2页
The theory of indirect speech acts proposed by John Searle is a problematic issue in speech act theory. The theory is subject to various criticisms.This essay reviews various arguments and the significant problems wit... The theory of indirect speech acts proposed by John Searle is a problematic issue in speech act theory. The theory is subject to various criticisms.This essay reviews various arguments and the significant problems with reference to the indirect speech acts. The review includes some important concepts of speech act theory which are related to indirect speech acts; inference theory and idiom theory which underline indirect speech acts and their major problems in accounting for indirect speech acts. 展开更多
关键词 speech act indirect speech speech act theory
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Indirect Radiative Forcing and Climatic Effect of the Anthropogenic Nitrate Aerosol on Regional Climate of China 被引量:14
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作者 李树 王体健 +1 位作者 庄炳亮 韩永 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2009年第3期543-552,共10页
The regional climate model (RegCM3) and a tropospheric atmosphere chemistry model (TACM) were coupled, thus a regional climate chemistry modeling system (RegCCMS) was constructed, which was applied to investigat... The regional climate model (RegCM3) and a tropospheric atmosphere chemistry model (TACM) were coupled, thus a regional climate chemistry modeling system (RegCCMS) was constructed, which was applied to investigate the spatial distribution of anthropogenic nitrate aerosols, indirect radiative forcing, as well as its climatic effect over China. TACM includes the thermodynamic equilibrium model ISORROPIA and a condensed gas-phase chemistry model. Investigations show that the concentration of nitrate aerosols is relatively high over North and East China with a maximum of 29μg m-3 in January and 8 μg m-3 in July. Due to the influence of air temperature on thermodynamic equilibrium, wet scavenging of precipitation and the monsoon climate, there are obvious seasonal differences in nitrate concentrations. The average indirect radiative forcing at the tropopause due to nitrate aerosols is -1.63 W m 2 in January and -2.65 W m 2 in July, respectively. In some areas, indirect radiative forcing reaches -10 W m-2. Sensitivity tests show that nitrate aerosols make the surface air temperature drop and the precipitation reduce on the national level. The mean changes in surface air temperature and precipitation are 0.13 K and -0.01 mm d-1 in January and -0.09 K and -0.11 mm d-1 in July, respectively, showing significant differences in different regions. 展开更多
关键词 nitrate aerosol indirect radiative forcing indirect climate effect regional climate atmosphericchemistry
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Indirect Methods of Detecting and Evaluating Inclusions in Steel—A Review 被引量:12
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作者 ZHANG Li-feng 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2006年第4期1-8,共8页
Indirect methods to detect and evaluate inclusions in steel are extensively reviewed, which include total oxygen content measurement, nitrogen pickup, steel and slag composition measurement, lining refractory observat... Indirect methods to detect and evaluate inclusions in steel are extensively reviewed, which include total oxygen content measurement, nitrogen pickup, steel and slag composition measurement, lining refractory observation, tracer studies of determining exogenous inclusions from slag and lining erosion, SEN clogging and final prod- uct tests. There is no single ideal method of detecting and evaluating inclusions in steel, so it is better to use several methods simultaneously to give a more accurate evaluation. Total oxygen content and nitrogen pickup in low carbon aluminum-killed steel as criterion of clean steel in many plants are summarized. 展开更多
关键词 INCLUSION indirect method total oxygen nitrogen pickup
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Electromagnetic Characteristic of Twin-wire Indirect Arc Welding 被引量:7
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作者 SHI Chuanwei ZOU Yong +1 位作者 ZOU Zengda WU Dongting 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第1期123-131,共9页
Traditional welding methods are limited in low heat input to workpiece and high welding wire melting rate. Twin-wire indirect arc(TWIA) welding is a new welding method characterized by high melting rate and low heat... Traditional welding methods are limited in low heat input to workpiece and high welding wire melting rate. Twin-wire indirect arc(TWIA) welding is a new welding method characterized by high melting rate and low heat input. This method uses two wires one connected to the negative electrode and another to the positive electrode of a direct-current(DC) power source. The workpiece is an independent, non-connected unit. A three dimensional finite element model of TWIA is devised. Electric and magnetic fields are calculated and their influence upon TWIA behavior and the welding process is discussed. The results show that with a 100 A welding current, the maximum temperature reached is 17 758 K, arc voltage is 14.646 V while maximum current density was 61 A/mm2 with a maximum Lorene force of 84.5 ~tN. The above mentioned arc parameters near the cathode and anode regions are far higher than those in the arc column region. The Lorene force is the key reason for plasma velocity direction deviated and charged particles flowed in the channel formed by the cathode, anode and upper part of arc column regions. This led to most of the energy being supplied to the polar and upper part of arc column regions. The interaction between electric and magnetic fields is a major determinant in shaping TWIA as well as heat input on the workpiece. This is a first study of electromagnetic characteristics and their influences in the TWIA welding process, and it is significant in both a theoretical and practical sense. 展开更多
关键词 twin-wire indirect arc welding ELECTROMAGNETIC SIMULATION
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Modeling Study of Aerosol Indirect Effectson Global Climate with an AGCM 被引量:4
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作者 王志立 张华 +2 位作者 沈学顺 龚山陵 张小曳 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2010年第5期1064-1077,共14页
Aerosol indirect effects (AIEs) on global climate were quantitatively investigated by introducing aerosol–cloud interaction parameterizations for water stratus clouds into an AGCM (BCC AGCM2.0.1), which was devel... Aerosol indirect effects (AIEs) on global climate were quantitatively investigated by introducing aerosol–cloud interaction parameterizations for water stratus clouds into an AGCM (BCC AGCM2.0.1), which was developed by the National Climate Center of the China Meteorological Administration. The study yielded a global annual mean of -1.14 W m^-2 for the first indirect radiative forcing (IRF), with an obvious seasonal change. In summer, large forcing mainly occurred in mid to high latitudes of the Northern Hemisphere, whereas in winter, large values were found at 60°S. The second indirect effect led to global annual mean changes in net shortwave flux of -1.03 W m^-2 at the top of the atmosphere (TOA), which was relatively significant in mid-latitude regions of both hemispheres. The total AIE reduced the global annual means of net shortwave flux at the TOA and of surface temperature by 1.93 W m^-2 and 0.12 K, respectively. Change in surface temperature induced by the total AIE was clearly larger in the Northern Hemisphere (-0.23 K) than in the Southern Hemisphere, where changes were negligible. The interhemispheric asymmetry in surface cooling resulted in significant differences in changes of the interhemispheric annual mean precipitation rate, which could lead to a tendency for the ITCZ to broaden. The total AIE decreased the global annual mean precipitation rate by 0.055 mm df^-1. 展开更多
关键词 AEROSOL CLOUD RADIATION indirect effect
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