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An exchange rate determination model for central banks'interventions in financial markets
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作者 林浚清 黄祖辉 战明华 《Journal of Zhejiang University Science》 CSCD 2002年第4期445-448,共4页
We establish an exchange rate determination model for central banks' interventions in financial markets. The model shows that central banks can adjust exchange rate by several policy instruments and that different... We establish an exchange rate determination model for central banks' interventions in financial markets. The model shows that central banks can adjust exchange rate by several policy instruments and that different instruments may have different effects on exchange rate determination. It specifies potential policy instruments for central banks as well as their policy effects. Based on these effects, feasible matches of policy instruments in contingent intervention are put forth. 展开更多
关键词 intervention of exchange rate Financial market Exchange rate determination
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Government Intervention Measures Effectively Control COVID-19 Epidemic in Wuhan,China 被引量:2
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作者 Xing XIN Shu-fang LI +6 位作者 Ling CHENG Chang-yu LIU Yin-juan XIN Hai-long HUANG Raijluxmee Beejadhursing Shao-shuai WANG Ling FENG 《Current Medical Science》 SCIE CAS 2021年第1期77-83,共7页
The coronavirus disease 2019(COVID-19)outbreak has been brought under control through a nationwide effort,and now it has become a global pandemic and the situation seems grim.We summarized the measures taken in Wuhan ... The coronavirus disease 2019(COVID-19)outbreak has been brought under control through a nationwide effort,and now it has become a global pandemic and the situation seems grim.We summarized the measures taken in Wuhan and analyzed the effects to comprehensively describe the factors involved in controlling the COVID-19 in China.In China,several measures such as the lockdown of Wuhan,restriction of traffic and communities,increasing hospital beds,nationwide support from medical staff,epidemic prevention equipment and supplies,and establishment of makeshift shelter hospitals have been taken.The lockdown of Wuhan reduced the propagation of cases to other cities in Hubei province and throughout China,traffic and community restrictions reduced the flow of population and the spread of disease,increasing wards and beds and medical personnel reduced the incidence of severe cases and mortality,the establishment of the Fangcang shelter hospitals provided a good isolation and monitoring environment,and further reduced the spread and fatality of the disease.The fact that China was able to control the spread of COVID-19 within three months without a specific drug or vaccine suggests that these measures are more adequate and effective. 展开更多
关键词 COVID-19 China's Mainland government intervention measures healthcare
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Analysis of the factors affecting the fuel rate in the COREX process and improvement measures 被引量:1
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作者 XU Wanren GUO Yanling WANG Chen 《Baosteel Technical Research》 CAS 2011年第1期45-50,共6页
Increasing production capacity and operating rate, reducing fuel rates and costs of hot metal (HM) are the urgent tasks for the COREX process. In this study ,the various factors on the fuel consumption of COREX are ... Increasing production capacity and operating rate, reducing fuel rates and costs of hot metal (HM) are the urgent tasks for the COREX process. In this study ,the various factors on the fuel consumption of COREX are researched from the theoretical analysis based on the calculations of material balances and heat balances. Combined with the production performances and practices of COREX-2000 ( Saldanha, India) and COREX-3000 ( Baosteel ), the technical measures of reducing the fuel rate are analyzed and the way forward of technical innovation is addressed and discussed with the standpoint of the COREX process improvement. 展开更多
关键词 COREX process reduction shaft (RS) melter-gasifier (MG) fuel rate improvement measures
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Analysis on psychological disorder and related factors in 98 patients with cancer and intervention measures thereon 被引量:1
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作者 Wenwu Wang Xuenong Ouyang Zhangshu Chen Xi Chen 《The Chinese-German Journal of Clinical Oncology》 CAS 2009年第8期488-491,共4页
Objective: The aim of this study was to analyze factors of psychological disorder experienced by 98 cancer patients and to probe into intervention measures in accordance with the corresponding bad psychological facto... Objective: The aim of this study was to analyze factors of psychological disorder experienced by 98 cancer patients and to probe into intervention measures in accordance with the corresponding bad psychological factors. Methods: A questionnaire survey was conducted in the test group (n = 98) by filling out a symptom checklist 90 (SCL-90). And then the survey result was compared with the normal group (n = 1388) contained in relevant references. Results: Except for hostile factor that was similar to normal level (P 〉 0.05), other 8 factors were higher than in normal group (P 〈 0.01). And the cancer patients were classified with the survey results. Conclusion: Compared with normal persons, cancer patients have more psychological problems and related intervention measures are sought necessarily to improve the quality of life, to advance the immune function and to prolong the survival time of patients. 展开更多
关键词 cancer patients PSYCHOLOGY syspton checklist 90 (SCL-90) analytic system intervention measures
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DECAY RATE OF FOURIER TRANSFORMS OF SOME SELF-SIMILAR MEASURES
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作者 高翔 马际华 《Acta Mathematica Scientia》 SCIE CSCD 2017年第6期1607-1618,共12页
This paper is concerned with the Diophantine properties of the sequence {ξθn}, where 1 ≤ξ 〈 θ and θ is a rational or an algebraic integer. We establish a combinatorial proposition which can be used to study suc... This paper is concerned with the Diophantine properties of the sequence {ξθn}, where 1 ≤ξ 〈 θ and θ is a rational or an algebraic integer. We establish a combinatorial proposition which can be used to study such two cases in the same manner. It is shown that the decay rate of the Fourier transforms of self-similar measures μλ with λ = θ-1 as the uniform contractive ratio is logarithmic. This generalizes some results of Kershner and Bufetov-Solomyak, who consider the case of Bernoulli convolutions. As an application, we prove that μλ ahaost every x is normal to any base b ≥ 2, which implies that there exist infinitely many absolute normal numbers on the corresponding self-similar set. This can be seen as a complementary result of the well-known Cassels-Schmidt theorem. 展开更多
关键词 self-similar measures Fourier transforms decay rate normal numbers
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Optimal use of fielder XT guidewire enhances the success rate of chronic total occlusion percutaneous coronary intervention
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作者 Qian-Cheng Wang Hai-Ruo Lin +8 位作者 Yuan Han Hai Dong Kai Xu Shao-Yi Guan Zhen-Huan Chen Hui-Xin Hao Jian-Ping Bin Yu-Lin Liao Quan-Min Jing 《World Journal of Clinical Cases》 SCIE 2019年第8期928-939,共12页
BACKGROUND Chronic total occlusion(CTO) is found in 18-31% of patients who undergo coronary angiography. Successful recanalization of CTOs is associated with reduced recurrent angina pectoris rates and increased long-... BACKGROUND Chronic total occlusion(CTO) is found in 18-31% of patients who undergo coronary angiography. Successful recanalization of CTOs is associated with reduced recurrent angina pectoris rates and increased long-term survival.Although the success rate of CTO percutaneous coronary intervention(CTO-PCI)has improved, CTO-PCI remains technically challenging. The Fielder XT guidewire was designed for CTO lesions. To validate whether the use of the guidewire increases the success rate, we compared the results of CTO-PCI with or without the guidewire. We hypothesized that the use of Fielder XT guidewire can increase the success rate of CTO-PCI.AIM To investigate whether the use of Fielder XT guidewire increases the final procedural success of CTO-PCI via the anterograde approach.METHODS Between January 2013 and December 2015, a retrospective study was conducted on 1230 consecutive patients with CTO who received PCI via the anterograde approach at the General Hospital of Northern Theater Command. The patients were divided into an XT Group(n = 686) and a no-XT Group(n = 544) depending on whether Fielder XT guidewire was used. Both groups were compared for clinical parameters, lesion-related characteristics, procedural outcomes and inhospital complications. The data were statistically analyzed using Pearson's χ~2 test for categorical variables, and Students' t test was used to compare the quantitative data. Significant independent factors and a risk ratio with 95%confidence interval(CI) were assessed by multivariate logistic regression analysis.RESULTS In total, 1230 patients were recruited; 75.4% of the patients were male, and 55.8%of the patients were in the XT group. The overall success rate was 83.9%, with87.8% in the XT group. Based on multivariate logistic regression analysis, factors positively associated with procedural success were the use of Fielder XT guidewire(P = 0.005, 95%CI: 1.172-2.380) and systolic blood pressure(P = 0.011,95%CI: 1.003-1.022), while factors negatively associated with procedural success were blunt stump(P = 0.013, 95%CI: 1.341-11.862), male sex(P = 0.016, 95%CI:0.363-0.902), New York Heart Association(NYHA) class(P = 0.035, 95%CI: 0.553-0.979), contrast amount(P = 0.018, 95%CI: 0.983-0.998) and occlusion time(P =0.009, 95%CI: 0.994-0.999). No significant differences were found between the XT group and the no-XT group with respect to clinical parameters, lesion-related characteristics, coronary artery rupture [3(0.4%) vs 8(1.5%), P = 0.056], inhospital death [2(0.3%) vs 6(1.1%), P = 0.079] or in-hospital target lesion revascularization [3(0.4%) vs 7(1.3%), P < 0.099]. However, there were significant differences between the groups with respect to success rate [602(87.8%) vs 430(79.0%), P < 0.001], procedure time [(74 ± 23) vs(83 ± 21), P < 0.001], stent length[(32.0 ± 15.8) vs(37.3 ± 17.6), P < 0.001], contrast amount [(148 ± 46) vs(166 ± 43),P < 0.001], post-PCI myocardial infarction [43(6.3%) vs 59(10.8%), P = 0.004],major adverse cardiovascular event [44(6.4%) vs 57(10.7%), P = 0.007], side branch loss [31(4.5%) vs 44(8.1%), P = 0.009], contrast-induced nephropathy [29(4.2%) vs 40(7.4%), P = 0.018] and no reflow [8(1.2%) vs 14(2.9%), P = 0.034].CONCLUSION The use of Fielder XT guidewire shortens the Procedure and increases the success rate of CTO-PCI, and is also associated with reduced complication rates. 展开更多
关键词 Chronic total occlusion Percutaneous coronary intervention ANTEROGRADE WIRE ESCALATION Parallel WIRE technique Fielder XT GUIDEWIRE Success rate
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The Effect of Percutaneous Coronary Intervention on Left Ventricular Diastolic Dysfunction in Patients with Coronary Artery Disease Assessed by Strain Rate Imaging
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作者 Fariba Bayat Elham Farahani Habibollah Saadat 《World Journal of Cardiovascular Diseases》 2014年第10期522-529,共8页
Introduction: Coronary artery disease (CAD) is the most common cause for left ventricular dysfunction. Unfortunately, the treatment strategies of regional myocardial diastolic dysfunction in patients with CAD have not... Introduction: Coronary artery disease (CAD) is the most common cause for left ventricular dysfunction. Unfortunately, the treatment strategies of regional myocardial diastolic dysfunction in patients with CAD have not been well characterized and benefit of percutaneous coronary intervention (PCI) as a treatment strategy is not clear. So the present study aimed to assess the effects of PCI on regional and global left ventricular diastolic dysfunction in patients with CAD assessed by strain rate (SR) imaging. Methods: Thirty adult symptomatic patients with coronary artery disease that underwent coronary angiography and candidate for PCI on left anterior descending artery were enrolled to our study. Echocardiographic findings and early diastolic SR were measured before and 48 hours after PCI. Results: Mean age of the patients was 59.9 ± 8.3 years. Most of the left ventricular diastolic parameters showed significant difference before and after elective PCI;while mitral E velocity, DT, E/A and pulmonary vein flow before and after PCI did not show significant difference assessed by statically test. Also before PCI, mean (SD) of peak early diastolic SR in ischemic regions (1.89 ± 0.22) was smaller than of non-ischemic regions (2.53 ± 0.26) while after PCI this parameter became similar in ischemic regions (2.55 ± 0.27) and non-ischemic regions (2.55 ± 0.26). Conclusion: Most of the left ventricular diastolic parameters improved after PCI in CAD patients. Also regional myocardial relaxation as measured by peak early diastolic SR (ESR) in the ischemic segments improved significantly compared with that in non-ischemic segments. 展开更多
关键词 Strain rate PERCUTANEOUS CORONARY intervention DIASTOLIC Function
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Current Situation and Mental Health and Intervention Measures of Left-behind Children
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作者 Hongze YANG 《Asian Agricultural Research》 2016年第12期53-56,共4页
In the Outline of the Twelfth Five-Year Plan for National Economic and Social Development of the People's Republic of China,it proposed of improving distribution and form of urbanization and strengthening urbaniza... In the Outline of the Twelfth Five-Year Plan for National Economic and Social Development of the People's Republic of China,it proposed of improving distribution and form of urbanization and strengthening urbanization management. With acceleration of the urbanization,numerous rural labors flow to cities,and the number of left-behind children becomes increasingly large,which not only increases burden of family and education,but also gives rise to many mental problems. Due to lack of family education,many left-behind children have mental,emotional and ethical disorder and problem,which creates hidden trouble for building a harmonious society and economic development. This paper analyzed current situation and factors influencing mental health of left-behind children,including family environment,grandparent upbringing,and school environment. Finally,it came up with pertinent intervention measures from changing ideas of parents,improving the relationship between parents and children,and improving mental health education of schools. 展开更多
关键词 Left-behind children Mental health Grandparent upbringing intervention measures
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Recent Experience of the Effects of Intervention on Exchange Rates
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作者 Yutaka Kurihara 《Chinese Business Review》 2013年第2期77-83,共7页
Recently, foreign exchange rates have been highly volatile all over the world. This article reports on an empirical examination of the effectiveness of foreign exchange market intervention in Tokyo foreign exchange ma... Recently, foreign exchange rates have been highly volatile all over the world. This article reports on an empirical examination of the effectiveness of foreign exchange market intervention in Tokyo foreign exchange market. In Japan, intervention in the foreign exchange market has occurred frequently and largely. In 2010, exchange rates fluctuated greatly, and the Japanese yen appreciated greatly against other foreign currencies. The Bank of Japan (BOJ) conducted an intervention in the foreign exchange market and bought massive USD to weaken the yen. They are expected to prevent too much appreciation of the yen, to promote export, and expansion of the economy. Recent foreign exchange market intervention in Tokyo has been effective in preventing the Japanese yen from appreciating against other currencies. Also, unsterilization has had a positive effect on depreciation of the yen. Moreover, news announcements by the Bank of Japan (BOJ) has led to depreciation of the yen. Effective announcements would increase the effects on markets. Sterilization in intervention and market communication are both taken into account in this article. The BOJ's news announcements seem to convey to markets adequately and communication between the bank and markets functions well. Moreover, the past exchange rate (i.e., the signaling effect) also is important to the movement of exchange rates. On the other hand, portfolio channel is not found 展开更多
关键词 exchange rate financial policy foreign exchange market intervention STERILIZATION TOKYO unsterilization
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Application of Intervention Measures in English Teaching
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作者 刘玉红 《海外英语》 2019年第23期263-264,共2页
Students often have problems of one kind or another in the process of learning English.How to solve these problems has always been an important topic in the education field.This paper starts with the analysis of the c... Students often have problems of one kind or another in the process of learning English.How to solve these problems has always been an important topic in the education field.This paper starts with the analysis of the characteristics of students'learning failure,and then puts forward the preconditions of effective interventions,and finally gives specific interventions. 展开更多
关键词 intervention measures English Teaching APPLICATION
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Improving IAC Algorithm Based on Range Rate Measurement 被引量:1
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作者 张鸿业 王月涌 蔡颖臻 《Journal of Beijing Institute of Technology》 EI CAS 1999年第3期276-281,共6页
Aim Interactive multiple model(IMM) algorithm was introduced into two? stage estimation to improve the estimating accuracy for system position and velocity.Methods The state estimation was carried out in mixed coor... Aim Interactive multiple model(IMM) algorithm was introduced into two? stage estimation to improve the estimating accuracy for system position and velocity.Methods The state estimation was carried out in mixed coordinates according to the nonlinear measure equation, a generalized interactive acceleration compensation(IAC) algorithm in mixed coordinate was presented. Results Simulation result shows the estimation accuracy is improved through changing measure equation in polar coordinates. Conclusion The estimation accuracy for position and velocity estimation, has been improved greatly, and the proposed algorithm has the advantage of less calculating time comparing with other multiple model methods. 展开更多
关键词 range rate measurement interactive acceleration compensation two-stage estimation
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Effects of acupuncture treatment on natural killer cell activity,pulse rate,and pain reduction for older adults:an uncontrolled,observational study 被引量:9
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作者 Hidetoshi Mori Hiroshi Kuge +3 位作者 Tim Hideaki Tanaka Eiichi Taniwaki Kazuyo Hanyu Tateyuki Morisawa 《Journal of Integrative Medicine》 SCIE CAS CSCD 2013年第2期101-105,共5页
OBJECTIVE: The aim of this study was to examine the changes in natural killer (NK) cell activity, pulse rate, and pain intensity among older adults before and after acupuncture treatment. METHODS: Fifty-six indivi... OBJECTIVE: The aim of this study was to examine the changes in natural killer (NK) cell activity, pulse rate, and pain intensity among older adults before and after acupuncture treatment. METHODS: Fifty-six individuals (16 males and 40 females), aged 60 to 82 years (mean age 72.4 + 5.0), who were experiencing pain in the shoulder, low back, or knee, participated in the study. NK cell activity, leukocyte differentiation (granulocytes and lymphocytes), pulse rate, and blood pressure values were obtained. Pain intensity was evaluated by using the visual analog scale (VAS). The Wilcoxon test was used to analyze NK cell activity, leukocytes (granulocyte counts and granulocyte-to-lymphocyte ratio), and the VAS score in accordance with the location of pain complaints before and after acupuncture treatment. RESULTS: NK cell activity decreased after acupuncture treatment for pain in the shoulder-pain and knee-pain groups. Further, the lymphocyte and granulocyte counts increased after acupuncture treatment for the shoulder-pain group. Pulse rate decreased for the shoulder-pain, low-back- pain, and knee-pain groups after acupuncture treatment. The VAS score decreased after acupuncture treatment for the shoulder-pain, low-back-pain, and knee-pain groups. CONCLUSION: This study showed that in older adults, acupuncture treatment decreases pulse rate, relieves pain in the shoulder, low back, and knee, and reduces NK-cell activity. 展开更多
关键词 acupuncture therapy killer cells natural leukocytes heart rate pain measurement clinical trial
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Crustal strain rates of southeastern Tibetan Plateau derived from GPS measurements and implications to lithospheric deformation of the Shan-Thai terrane 被引量:7
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作者 KeLiang Zhang ShiMing Liang WeiJun Gan 《Earth and Planetary Physics》 CSCD 2019年第1期45-52,共8页
The link between the crustal deformation and mantle kinematics in the Tibetan Plateau has been well known thanks to dense GPS measurements and the relatively detailed anisotropy structure of the lithospheric mantle.Ho... The link between the crustal deformation and mantle kinematics in the Tibetan Plateau has been well known thanks to dense GPS measurements and the relatively detailed anisotropy structure of the lithospheric mantle.However, whether the crust deforms coherently with the upper mantle in the Shan-Thai terrane(also known as the Shan-Thai block) remains unclear.In this study, we investigate the deformation patterns through strain rate tensors in the southeastern Tibetan Plateau derived from the latest GPS measurements and find that in the Shan-Thai terrane the upper crust may be coupled with the lower crust and the upper mantle.The GPS-derived strain rate tensors are in agreement with the slipping patterns and rates of major strike-slip faults in the region.The most prominent shear zone, whose shear strain rates are larger than 100×10^(–9) a^(–1), is about 1000-km-long in the west, trending northward along Sagaing fault to the Eastern Himalayan Syntaxis in the north, with maximum rate of compressive strain up to –240×10^(–9) a^(–1).A secondary shear zone along the Anninghe-Xiaojiang Fault in the east shows segmented shear zones near several conjunctions.While the strain rate along RRF is relatively low due to the low slip rate and low seismicity there, in Lijiang and Tengchong several local shear zones are present under an extensional dominated stress regime that is related to normal faulting earthquakes and volcanism, respectively.Furthermore, by comparing GPS-derived strain rate tensors with earthquake focal mechanisms, we find that 75.8%(100 out of 132) of the earthquake T-axes are consistent with the GPS-derived strain rates.Moreover, we find that the Fast Velocity Direction(FVDs) at three depths beneath the Shan-Thai terrane are consistent with extensional strain rate with gradually increasing angular differences, which are likely resulting from the basal shear forces induced by asthenospheric flow associated with the oblique subduction of the India plate beneath the Shan-Thai terrane.Therefore, in this region the upper crust deformation may be coherent with that of the lower crust and the lithospheric mantle. 展开更多
关键词 strain rate TENSOR GPS measurement LITHOSPHERIC deformation southeastern TIBETAN PLATEAU Shan-Thai TERRANE
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Field Measurements of Influence of Sand Transport Rate on Structure of Wind-sand Flow over Coastal Transverse Ridge 被引量:10
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作者 DONG Yuxiang S L NAMIKAS +1 位作者 P A HESP MA Jun 《Chinese Geographical Science》 SCIE CSCD 2008年第3期255-261,共7页
The structure of wind-sand flow under different total sand transport rates was measured with field vertical anemometer and sand trap on the crest of typical coastal transverse ridge in Changli Gold Coast of Hebei Prov... The structure of wind-sand flow under different total sand transport rates was measured with field vertical anemometer and sand trap on the crest of typical coastal transverse ridge in Changli Gold Coast of Hebei Province, which is one of the most typical coastal aeolian distribution regions in China and famous for the tall and typical coastal transverse ridges. The measurement results show that, on the conditions of approximate wind velocities and same surface materials and environments, some changes happen to the structure of wind-sand flow with the increase of total sand transport rate on the crest of coastal transverse ridge. First, the sand transport rates of layers at different heights in the wind-sand flow increase, with the maximum increase at the height layer of 4-8cm. Second, the ratios of sand trans-port rates of layers at different heights to total sand transport rate decrease at the low height layer (0-4cm), but increase at the high height layer (4-60cm). Third, the distribution of the sand transport rate in the wind-sand flow can be expressed by an exponential function at the height layer of 0-40cm, but it changes from power function model to ex-ponential function model in the whole height layer (0-60cm) and changes into polynomial function model at the height layer of 40-60cm with the increase of total sand transport rate. Those changes have a close relationship with the limit of sand grain size of wind flow transporting and composition of sand grain size in the wind-sand flow. 展开更多
关键词 sand transport rate coastal transverse ridge structure of wind-sand flow field measurement
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Self-heating Probe Instrument and Method for Measuring High Temperature Melting Volume Change Rate of Material 被引量:2
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作者 WANG Junwei WANG Zhiping +1 位作者 LU Yang CHENG Bo 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2013年第2期371-376,共6页
The castings defects are affected by the melting volume change rate of material. The change rate has an important effect on running safety of the high temperature thermal storage chamber, too. But the characteristics ... The castings defects are affected by the melting volume change rate of material. The change rate has an important effect on running safety of the high temperature thermal storage chamber, too. But the characteristics of existing measuring installations are complex structure, troublesome operation and low precision. In order to measure the melting volume change rate of material accurately and conveniently, a self-designed measuring instrument, self-heating probe instrument, and measuring method are described. Temperature in heating cavity is controlled by PID temperature controller; melting volume change rate υ and molten density are calculated based on the melt volume which is measured by the instrument. Positive and negative υ represent expansion and shrinkage of the sample volume after melting, respectively. Taking eutectic LiF+CaF2 for example, its melting volume change rate and melting density at 1 123 K are -20.6% and 2 651 kg/m–3 measured by this instrument, which is only 0.71% smaller than literature value. Density and melting volume change rate of industry pure aluminum at 973 K and analysis pure NaCl at 1 123 K are detected by the instrument too. The measure results are agreed with report values. Measuring error sources are analyzed and several improving measures are proposed. In theory, the measuring errors of the change rate and molten density which are measured by the self-designed instrument is nearly 1/20-1/50 of that measured by the refitted mandril thermal expansion instrument. The self-designed instrument and method have the advantages of simple structure, being easy to operate, extensive applicability for material, relatively high accuracy, and most importantly, temperature and sample vapor pressure have little effect on the measurement accuracy. The presented instrument and method solve the problems of complicated structure and procedures, and large measuring errors for the samples with high vapor pressure by existing installations. 展开更多
关键词 high temperature volume expansion rate molten density measuring instrument measuring method
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Does heart rate variability correlate with long-term prognosis in myocardial infarction patients treated by early revascularization? 被引量:10
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作者 Leonida Compostella Nenad Lakusic +3 位作者 Caterina Compostella Li Van Stella Truong Sabino Iliceto Fabio Bellotto 《World Journal of Cardiology》 CAS 2017年第1期27-38,共12页
AIMTo assess the prevalence of depressed heart rate variability (HRV) after an acute myocardial infarction (MI), and to evaluate its prognostic significance in the present era of immediate reperfusion.METHODSTime-doma... AIMTo assess the prevalence of depressed heart rate variability (HRV) after an acute myocardial infarction (MI), and to evaluate its prognostic significance in the present era of immediate reperfusion.METHODSTime-domain HRV (obtained from 24-h Holter recordings) was assessed in 326 patients (63.5 ± 12.1 years old; 80% males), two weeks after a complicated MI treated by early reperfusion: 208 ST-elevation myocardial infarction (STEMI) patients (in which reperfusion was successfully obtained within 6 h of symptoms in 94% of cases) and 118 non-ST-elevation myocardial infarction (NSTEMI) patients (percutaneous coronary intervention was performed within 24 h and successful in 73% of cases). Follow-up of the patients was performed via telephone interviews a median of 25 mo after the index event (95%CI of the mean 23.3-28.0). Primary end-point was occurrence of all-cause or cardiac death; secondary end-point was occurrence of major clinical events (MCE, defined as mortality or readmission for new MI, new revascularization, episodes of heart failure or stroke). Possible correlations between HRV parameters (mainly the standard deviation of all normal RR intervals, SDNN), clinical features (age, sex, type of MI, history of diabetes, left ventricle ejection fraction), angiographic characteristics (number of coronary arteries with critical stenoses, success and completeness of revascularization) and long-term outcomes were analysed.RESULTSMarkedly depressed HRV parameters were present in a relatively small percentage of patients: SDNN < 70 ms was found in 16% and SDNN < 50 ms in 4% of cases. No significant differences were present between STEMI and NSTEMI cases as regards to their distribution among quartiles of SDNN (χ<sup>2</sup> =1.536, P = 0.674). Female sex and history of diabetes maintained a significant correlation with lower values of SDNN at multivariate Cox regression analysis (respectively: P = 0.008 and P = 0.008), while no correlation was found between depressed SDNN and history of previous MI (P = 0.999) or number of diseased coronary arteries (P = 0.428) or unsuccessful percutaneous coronary intervention (PCI) (P = 0.691). Patients with left ventricle ejection fraction (LVEF) < 40% presented more often SDNN values in the lowest quartile (P < 0.001). After > 2 years from infarction, a total of 10 patients (3.1%) were lost to follow-up. Overall incidence of MCE at follow-up was similar between STEMI and NSTEMI (P = 0.141), although all-cause and cardiac mortality were higher among NSTEMI cases (respectively: 14% vs 2%, P = 0.001; and 10% vs 1.5%, P = 0.001). The Kaplan-Meier survival curves for all-cause mortality and for cardiac deaths did not reveal significant differences between patients with SDNN in the lowest quartile and other quartiles of SDNN (respectively: P = 0.137 and P = 0.527). Also the MCE-free survival curves were similar between the group of patients with SDNN in the lowest quartile vs the patients of the other SDNN quartiles (P = 0.540), with no difference for STEMI (P = 0.180) or NSTEMI patients (P = 0.541). By the contrary, events-free survival was worse if patients presented with LVEF < 40% (P = 0.001).CONCLUSIONIn our group of patients with a recent complicated MI, abnormal autonomic parameters have been found with a prevalence that was similar for STEMI and NSTEMI cases, and substantially unchanged in comparison to what reported in the pre-primary-PCI era. Long-term outcomes did not correlate with level of depression of HRV parameters recorded in the subacute phase of the disease, both in STEMI and in NSTEMI patients. These results support lack of prognostic significance of traditional HRV parameters when immediate coronary reperfusion is utilised. 展开更多
关键词 Heart rate variability Autonomic nervous system Primary percutaneous coronary intervention Myocardial infarction ST-elevation myocardial infarction Non-ST-elevation myocardial infarction Left ventricle ejection fraction Long-term prognosis
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STUDIES ON CULTURE CONDITIONS OF BENTHIC DIATOMS FOR FEEDING ABALONE I.EFFECTS OF TEMPERATURE AND LIGHT INTENSITY ON GROWTH RATE 被引量:1
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作者 王起华 王淑红 +3 位作者 丁明进 李梅 石若夫 程爱华 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1997年第4期296-303,共8页
Effects of temperature and light intensity on the groWth rate of four species of benthic diatoms for feeding abalone were studied by using a novel method (in situ optical density measurement)which was simple, convenie... Effects of temperature and light intensity on the groWth rate of four species of benthic diatoms for feeding abalone were studied by using a novel method (in situ optical density measurement)which was simple, convenient, fast, accurate and reliable for determining biomass of benthic algae. The results showed that the favourable temperature and light intensity were as follows: for Amphora coffeaeformis, 30℃, 18 W/m2 for Cocconeis scutellum var. parv. 18℃, 20 W/m2; for Navicula Corymbosa, 18℃. 12.4 W/m2;for Navicula mollis, 24℃, 6 W/m2. 展开更多
关键词 BENTHIC DIATOMS culture condition growth rate in SITU OD measurement
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Methodology for production logging in oil-in-water flows under low flow rate and high water-cut conditions 被引量:2
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作者 Wang Da-Yang Jin Ning-De +2 位作者 Zhai Lu-Sheng Ren Ying-Yu He Yuan-Sheng 《Applied Geophysics》 SCIE CSCD 2019年第3期302-313,395,共13页
This study aimed to obtain the production profiles of oil-in-water flow under low flow rate and high water-cut conditions in oil wells.A combination production profile logging composed of an arc-type conductance senso... This study aimed to obtain the production profiles of oil-in-water flow under low flow rate and high water-cut conditions in oil wells.A combination production profile logging composed of an arc-type conductance sensor(ATCS)and a cross-correlation flow meter(CFM)with a center body is proposed and experimentally evaluated.The ATCS is designed for water holdup measurement,whereas the CFM with a center body is proposed to obtain the mixture velocity.Then,a drift-flux model based on flow patterns is established to predict the individual-phase superficial velocity of oil-in-water flows.Results show that the ATCS possesses high resolution in water holdup measurement and that flow pattern information can be deduced from its signal through nonlinear time series analysis.The CFM can enhance the correlation of upstream and downstream signals and simplify the relationship between the cross-correlation velocity and mixture velocity.On the basis of the drift-flux model,individual-phase superficial velocities can be predicted with high accuracy for different flow patterns. 展开更多
关键词 oil-in-water flows low flow rate high water-cut conductance sensor flow meter measurement model
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Single-Channel Speech Enhancement Using Critical-Band Rate Scale Based Improved Multi-Band Spectral Subtraction 被引量:1
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作者 Navneet Upadhyay Abhijit Karmakar 《Journal of Signal and Information Processing》 2013年第3期314-326,共13页
This paper addresses the problem of single-channel speech enhancement in the adverse environment. The critical-band rate scale based on improved multi-band spectral subtraction is investigated in this study for enhanc... This paper addresses the problem of single-channel speech enhancement in the adverse environment. The critical-band rate scale based on improved multi-band spectral subtraction is investigated in this study for enhancement of single-channel speech. In this work, the whole speech spectrum is divided into different non-uniformly spaced frequency bands in accordance with the critical-band rate scale of the psycho-acoustic model and the spectral over-subtraction is carried-out separately in each band. In addition, for the estimation of the noise from each band, the adaptive noise estimation approach is used and does not require explicit speech silence detection. The noise is estimated and updated by adaptively smoothing the noisy signal power in each band. The smoothing parameter is controlled by a-posteriori signal-to-noise ratio (SNR). For the performance analysis of the proposed algorithm, the objective measures, such as, SNR, segmental SNR, and perceptual evaluations of the speech quality are conducted for the variety of noises at different levels of SNRs. The speech spectrogram and objective evaluations of the proposed algorithm are compared with other standard speech enhancement algorithms and proved that the musical structure of the remnant noise and background noise is better suppressed by the proposed algorithm. 展开更多
关键词 SINGLE-CHANNEL SPEECH Enhancement Critical-Band rate SCALE Spectral Over-Subtraction Adaptive Noise Estimation Objective Measure SPEECH Spectrograms
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Partial phase flow rate measurements for stratified oil-water flow in horizontal wells 被引量:1
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作者 SONG Hongwei GUO Haimin +1 位作者 GUO Shuai SHI Hangyu 《Petroleum Exploration and Development》 2020年第3期613-622,共10页
To accurately measure and evaluate the oil-water production profile of horizontal wells, a dynamic measurement experiment of oil-water two-phase flow in horizontal wells and numerical simulation were combined to estab... To accurately measure and evaluate the oil-water production profile of horizontal wells, a dynamic measurement experiment of oil-water two-phase flow in horizontal wells and numerical simulation were combined to establish a method for measuring the partial phase flow rate of oil-water two-phase stratified flow in horizontal wells. An experimental work was performed in horizontal oil-water two-phase flow simulation well using combination production logging tool including mini-capacitance sensor and mini-spinner. The combination tool provides a recording of holdup and velocity profiles at five different heights of the borehole cross-section. The effect of total flow rate and water-cut on the response of spinner and capacitive sensor at five measured positions were investigated. The capacitance water holdup interpolation imaging algorithm was used to determine the local fluid property and oil-water interface height, and the measured local fluid speed was combined with the numerical simulation result to establish an optimal calculation model for obtaining the partial phase flow rate of the oil-water two-phase stratified flow in the horizontal well. The calculated flow rates of five measured points are basically consistent with the experimental data, the total flow rate and water holdup from calculation are in agreement with the set values in the experiment too, suggesting that the method has high accuracy. 展开更多
关键词 horizontal well oil-water two-phase flow stratified flow regime flow rate measurement fluid dynamics experiment production logging
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