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A Comparative Study on Achievements in Negative Nominal Interest Rates Published in Literature in English and Chinese
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作者 Yu Yuxin Wu Zhiyun 《Contemporary Social Sciences》 2023年第3期43-64,共22页
Interest rates are the key to the resource allocations of financial markets.The frequent appearance of negative nominal interest rates(NNIR)may lead to a failure of the transmission mechanism and arouse system risks i... Interest rates are the key to the resource allocations of financial markets.The frequent appearance of negative nominal interest rates(NNIR)may lead to a failure of the transmission mechanism and arouse system risks in the financial markets.Meanwhile,negative nominal interest rates is a new policy with no consensus reached by academia or policymakers.It is necessary to review the research results and promote consensus to reveal the nature and impact mechanisms of NNIR.Therefore,we retrieved original articles from the Web of Science(WoS)and China National Knowledge Infrastructure(CNKI)published from 1999 to 2020 on NNIR to determine the characteristics of current research results from various perspectives and compare literature in English and Chinese of highly productive institutions and researchers,hot topics,evolution contexts,research frontiers,and ecological characteristics.There are three major findings.In terms of research ecology,the ecological structure of the top research institutions,both domestic and abroad,remains steady,but the structure of the researchers is not stable.In terms of a research domain,NNIR is studied from many dimensions,and the early established research domains still have long-lasting impacts in English literature.In contrast,Chinese literature mainly focuses on discussing applicable policies with no highly focused domain and research topic with great influence yet.Finally,the focus in both English and Chinese literature has changed.Since the original research framework is insufficient in explanatory power,literature in English is beginning to pay attention to the empirical analyses of practical policies,and Chinese scholars are turning to theoretical study to enhance the in-depth understanding of this phenomenon.Researchers in China should focus on collecting high-quality research materials and pay more attention to the progress of empirical research in English literature to improve Chinese research efficiency and quality and then promote research progress in China. 展开更多
关键词 negative nominal interest rates(NNIR) BIBLIOMETRICS social network analysis cluster analysis
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On the Distribution of Duration of First Negative Surplus for a Discrete Time Risk Model with Random Interest Rate
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作者 汪荣明 吴贤毅 《Northeastern Mathematical Journal》 CSCD 2006年第3期299-305,共7页
In this paper, we examine further annuity-due risk model presented by Cai (Probability in the Engineering and Informational Sciences, 16(2002), 309-324). We consider the computation for the distribution of duratio... In this paper, we examine further annuity-due risk model presented by Cai (Probability in the Engineering and Informational Sciences, 16(2002), 309-324). We consider the computation for the distribution of duration of first negative surplus and the algorithm is shown for calculating probability that ruin occurs and the duration of first negative surplus takes any nonnegative integers values. Numerical illustration for the main result is given. 展开更多
关键词 discrete time risk model random interest rate annuity-due risk model duration of negative surplus
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Economic uncertainty,central bank digital currency,and negative interest rate policy
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作者 Baogui Xin Kai Jiang 《Journal of Management Science and Engineering》 CSCD 2023年第4期430-452,共23页
The covID-19 outbreak has brought unprecedented social attention to economic uncertainty and negative interest rate policy(NIRP).How does uncertainty affect economic activity,and how effective is a NIRP based on centr... The covID-19 outbreak has brought unprecedented social attention to economic uncertainty and negative interest rate policy(NIRP).How does uncertainty affect economic activity,and how effective is a NIRP based on central bank digital currency(CBDC)?To answer the two questions,we constructed a dynamic stochastic general equilibrium(DSGE)model that accommodates sticky prices and wages.The results indicated:(i)Economic uncertainty has substantially reduced investment,output,wage,and loans,which increases unemployment risk.In the short term,it has triggered impulsive consumption by households,while consumption has fallen into a slump in the long run.(ii)After suffering an uncertainty shock,the economy entered short-term stagflation and long-term deflation.The short-term stagflation was mainly caused by resident wage adjustment,and the long-term deflation was due to the decline in effective demand caused by unemployment risk.(ii)CBDC could eliminate the zero lower bound(ZLB)constraint,thereby improving the effectiveness of NIRP.Compared with traditional currency,CBDCbased NIRP could more effectively smooth macroeconomic fluctuations and alleviate the negative impact of an uncertainty shock,which is more conducive to restoring market confidence and promoting economic recovery. 展开更多
关键词 Economic uncertainty Zero lower bound(ZLB) Central bank digital currency(CBDC) negative interest rate policy(NIRP)
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Could we remain simply applying discount rate to evaluate the life quality of our future generations?
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作者 Yuko Arayama 《Chinese Journal of Population,Resources and Environment》 2013年第2期168-173,共6页
When we try to estimate future environmental costs resulting from our current economic activities,we usually calculate the present value of the consequences for our future generations by utilizing a discount rate as a... When we try to estimate future environmental costs resulting from our current economic activities,we usually calculate the present value of the consequences for our future generations by utilizing a discount rate as a standard economic procedure.The popularity of this procedure is solely supported by its simplicity which assumes:(1)a perfect financial market over even 100 years,and(2)existence of a stable time preference between two consecutive periods for an individual consumer.An apparent deficiency of this approach is that the present value of life quality of future generations varies to a large extent along an arbitrarily chosen discount rate.As a matter of fact,the discount rate,which could reflect the time preference as2%or 5%,matters when we predict current strategies of environmental protection for future generations.Simply applying a discount rate to evaluate the quality of our future generation,without clarifying the actual production mechanism behind this,is almost to the same as ignoring the fact that all of the goods are produced through an actual production process and that environmental degradation reduces the efficiency of that process.The greatest concern for our future generations should not be given by an assumed discount rate,since the discount rate itself is determined by financial market conditions at certain points in time. 展开更多
关键词 time PREFERENCE DISCOUNT rate negative externalities future generations
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Piketty’s Capital-Income Theory Reconsidered for a Small Open Economy with Increasing Savings Rate
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作者 Yasunori Fujita 《Open Journal of Statistics》 2016年第1期25-30,共6页
Since Piketty offered a new view of capital/income ratio, numerous attempts have been made to examine the relationship between return on capital, economic growth and the capital/income ratio. This paper attempts to sh... Since Piketty offered a new view of capital/income ratio, numerous attempts have been made to examine the relationship between return on capital, economic growth and the capital/income ratio. This paper attempts to shed new light on this field. More precisely, following recent literatures that pay attention to dynamics of external balance sheets of countries, we examine if Piketty’s results for large countries are robust for a country that takes the world rate of return on capital as given and whose savings rate increases gradually from negative value. It is revealed that for such a country, (1) Kuznets curve is drawn and (2) capital/income ratio decreases in accordance with a rise in savings rate and return on capital. 展开更多
关键词 Small Open Economy Capital/Income Ratio Kuznets Curve negative Savings rate
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Decline of oil prices and the negative interest rate policy in Japan 被引量:2
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作者 Naoyuki Yoshino Farhad Taghizadeh-Hesary Nour Tawk 《Economic and Political Studies》 2017年第2期233-250,共18页
In April 2013,the Bank of Japan(BOJ)introduced an inflation target of 2%with the aim of overcoming deflation and achieving sustainable economic growth.But due to lower international oil prices it was unable to achieve... In April 2013,the Bank of Japan(BOJ)introduced an inflation target of 2%with the aim of overcoming deflation and achieving sustainable economic growth.But due to lower international oil prices it was unable to achieve this target and was forced to take further measures.Hence,in February 2016,the BOJ adopted a negative interest rate policy by massively increasing the money supply through the purchase of long-term Japanese government bonds(JGB).The BOJ had previously only purchased short-term government bonds,a policy that flattened the yield curve of JGBs.On the one hand,banks reduced the number of government bonds they purchased because short-term bond yields had become negative.The interest rates of long-term government bond up to 15 years even became negative.On the other hand,bank loans to corporates did not increase,due to Japanese economy’s vertical investment-saving(IS)curve.The purpose of this paper is to show that the monetary policy through implementation of the zero interest rate and more recently through the negative interest rate could not help the Japanese economy to recover from the long-lasting recession and these are not the remedy.It is of key importance to make the IS curve downward rather than vertical.That means the rate of return on investment must be positive and companies must be willing to invest even if interest rates are set too low.Japan’s long-term recession is due to structural problems that cannot be solved by its current monetary policy.The paper also explains why the BOJ has to reduce its 2%inflation target in the present low oil price era. 展开更多
关键词 negative interest rate policy Japanese economy oil price Abenomics
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自行下体负压训练器锻炼对心血管功能及下体负压耐力的影响 被引量:2
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作者 杨长斌 孙喜庆 +3 位作者 王永春 刘挺松 冯岱雅 姚永杰 《航天医学与医学工程》 CAS CSCD 北大核心 2004年第3期192-195,共4页
目的探讨利用自行下体负压训练器锻炼后心血管功能及下体负压耐力的变化 ,为其应用提供实验依据。方法 1 2名健康男性被试者随机分为两组 ,分别在进气阀门完全关闭 (A组 )、进气阀门打开至峰值负压为 - 30mmHg(B组 )两种状态下进行锻炼... 目的探讨利用自行下体负压训练器锻炼后心血管功能及下体负压耐力的变化 ,为其应用提供实验依据。方法 1 2名健康男性被试者随机分为两组 ,分别在进气阀门完全关闭 (A组 )、进气阀门打开至峰值负压为 - 30mmHg(B组 )两种状态下进行锻炼。A组锻炼持续时间为 5d ,3min/d ,分别于锻炼前、锻炼 3、5d后进行心脏泵血功能及头高位倾斜检查 ,进行短程心率变异性分析 ,锻炼前后行下体负压耐力检查。B组锻炼持续时间为 1 0d ,5min/d ,分别于锻炼前、锻炼 5、8、1 0d后进行各项检查 ,检查项目与A组相同。结果A组锻炼后 ,心脏泵血功能显著降低 ,下体负压耐力显著升高。B组心脏泵血功能则在锻炼 8d后显著增强 ,下体负压耐力也显著提高。结论利用自行下体负压训练器进行锻炼 ,可以显著提高下体负压耐力 ,但训练方案不同心血管功能的改变也不同。 展开更多
关键词 心血管功能 训练 心率变异性 下体负压 耐力
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将然否定重复频率语块“不再VP”和“再不VP”比较
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作者 王秋萍 《沈阳师范大学学报(社会科学版)》 2022年第5期61-67,共7页
由否定副词“不”,表示将要重复的动作或持续的状态意义的频度副词“再”与VP共同组成将然否定重复频率语块“不再VP”和“再不VP”。两个语块均表达事件过程、频度、状态、结果的否定性改变,有时同时表达出言者主观性的观点、立场、决... 由否定副词“不”,表示将要重复的动作或持续的状态意义的频度副词“再”与VP共同组成将然否定重复频率语块“不再VP”和“再不VP”。两个语块均表达事件过程、频度、状态、结果的否定性改变,有时同时表达出言者主观性的观点、立场、决心,以及告别过去的心理状态变化。但两者在将然否定重复功能方面存在四点差异:第一,终止时间域大小、终止时效性长短不同;第二,语气轻重不同;第三,将然否定重复语义指向时间域方向不同;第四,动作、状态转变或情感转变的表达侧重点不同。调查所见,“不再VP”常用于客观陈述的叙述体,少用于对话体,“再不VP”用于对话体频次远高于“不再VP”,更多呈现主观性表述与情感表达。 展开更多
关键词 将然否定重复频率语块 不再VP 再不VP
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Effects of Tanreqing Capsule on the negative conversion time of nucleic acid in patients with COVID-19:A retrospective cohort study 被引量:10
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作者 Xing Zhang Yan Xue +13 位作者 Xuan Chen Jia-min Wu Zi-jian Su Meng Sun Lu-jiong Liu Yi-bao Zhang Yi-le Zhang Gui-hua Xu Miao-yan Shi Xiu-ming Song Yun-fei Lu Xiao-rong Chen Wei Zhang Qi Chen 《Journal of Integrative Medicine》 SCIE CAS CSCD 2021年第1期36-41,共6页
Objective:Traditional Chinese medicine plays a significant role in the treatment of the pandemic of coronavirus disease 2019(COVID-19).Tanreqing Capsule(TRQC)was used in the treatment of COVID-19 patients in the Shang... Objective:Traditional Chinese medicine plays a significant role in the treatment of the pandemic of coronavirus disease 2019(COVID-19).Tanreqing Capsule(TRQC)was used in the treatment of COVID-19 patients in the Shanghai Public Health Clinical Center.This study aimed to investigate the clinical efficacy of TRQC in the treatment of COVID-19.Methods:A retrospective cohort study was conducted on 82 patients who had laboratory-confirmed mild and moderate COVID-19;patients were treated with TRQC in one designated hospital.The treatment and control groups consisted of 25 and 57 cases,respectively.The treatment group was given TRQC orally three times a day,three pills each time,in addition to conventional Western medicine treatments which were also administered to the control group.The clinical efficacy indicators,such as the negative conversion time of pharyngeal swab nucleic acid,the negative conversion time of fecal nucleic acid,the duration of negative conversion of pharyngeal-fecal nucleic acid,and the improvement in the level of immune indicators such as T-cell subsets(CD3,CD4 and CD45)were monitored.Results:COVID-19 patients in the treatment group,compared to the control group,had a shorter negative conversion time of fecal nucleic acid(4 vs.9 days,P=0.047)and a shorter interval of negative conversion of pharyngeal-fecal nucleic acid(0 vs.2 days,P=0.042).The level of CD3+T cells increased in the treatment group compared to the control group([317.09±274.39]vs.[175.02±239.95]counts/l L,P=0.030).No statistically significant differences were detected in the median improvement in levels of CD4+T cells(173 vs.107 counts/l L,P=0.208)and CD45+T cells(366 vs.141 counts/l L,P=0.117)between the treatment and control groups.Conclusion:Significant reductions in the negative conversion time of fecal nucleic acid and the duration of negative conversion of pharyngeal-fecal nucleic acid were identified in the treatment group as compared to the control group,illustrating the potential therapeutic benefits of using TRQC as a complement to conventional medicine in patients with mild and moderate COVID-19.The underlying mechanism may be related to the improved levels of the immune indicator CD3+T cells. 展开更多
关键词 Tanreqing Capsule Coronavirus disease 2019 COVID-19 diagnostic testing negative conversion rate
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Fabrication and anodic polarization behavior of lead-based porous anodes in zinc electrowinning 被引量:3
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作者 衷水平 赖延清 +4 位作者 蒋良兴 吕晓军 陈佩如 李劼 刘业翔 《Journal of Central South University of Technology》 EI 2008年第6期757-762,共6页
A new type of lead-based porous anode in zinc electrowinning was prepared by negative pressure infiltration. The anodic polarization potential and corrosion rate were studied and compared with those of traditional fia... A new type of lead-based porous anode in zinc electrowinning was prepared by negative pressure infiltration. The anodic polarization potential and corrosion rate were studied and compared with those of traditional fiat anodes (Pb-0.8%Ag) used in industry. The anode corrosion rate was determined by anode actual current density and microstructure. The results show that the anodic oxygen evolution potential decreases first and then increases with the decrease of pore diameter. The anodic potential decreases to the lowest value of 1.729 V at the pore diameter of 1.25-1.60 mm. The porous anode can decrease its actual current density and thus decrease the anodic corrosion rate. When the pore diameter is 1.60-2.00 mm, the anodic relative corrosion rate reaches the lowest value of 52.1%. 展开更多
关键词 zinc electrowinning negative pressure infiltration porous anode anode potential corrosion rate
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Homogeneous catalytic wet air oxidation for the treatment of textile wastewaters 被引量:2
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作者 Lei, L. Sun, Y. 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2000年第4期410-415,共6页
An extensive series of experiments was carried out in order to identify suitable catalysts to boost the reaction rate of wet air oxidation of real textile wastewaters at relatively mild temperature and pressure. Exper... An extensive series of experiments was carried out in order to identify suitable catalysts to boost the reaction rate of wet air oxidation of real textile wastewaters at relatively mild temperature and pressure. Experimental results indicated that all catalysts tested in this investigation had shown an impressive increase in the initial COD and TOC removal rate as well as the COD and TOC removal levels in two hours reaction. Among all the catalysts tested, copper salts were more effective than the rest. Anions of the salt solutions also played a role in the catalytic process with nitrate ions having better effect than sulfate ions. Hence copper nitrates were more effective than copper sulfates. It was also found that a mixture of salts with different metals performed better than either of the component single salt alone. 展开更多
关键词 CATALYSIS Chemical oxygen demand Copper compounds Low temperature effects negative ions NITrateS OXIDATION Pressure effects rate constants SALTS
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ASYMPTOTIC BEHAVIOR OF THE STOKES APPROXIMATION EQUATIONS FOR COMPRESSIBLE FLOWS IN R^3 被引量:1
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作者 吴云顺 谭忠 《Acta Mathematica Scientia》 SCIE CSCD 2015年第3期746-760,共15页
We consider the Stokes approximation equations for compressible flows in /~3. The global unique solution and optimal convergence rates are obtained by pure energy method provided the initial perturbation around a cons... We consider the Stokes approximation equations for compressible flows in /~3. The global unique solution and optimal convergence rates are obtained by pure energy method provided the initial perturbation around a constant state is small. In particular, the optimal decay rates of the higher-order spatial derivatives of the solution are obtained. As an imme- diate byproduct, the usual Lp - L2(1 〈 p 〈 2) type of the optimal decay rate follow without requiring that the Lp norm of initial data is small. 展开更多
关键词 Stokes approximation equations energy method optimal decay rates Sobolevinterpolation negative Sobolev space
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Short Term Efficacy of Entecavir in the Treatment of Decompensated Chronic Hepatitis B Cirrhosis
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作者 Weiwei Fu 《Proceedings of Anticancer Research》 2020年第6期53-56,共4页
Objective:To explore the effect of entecavir on patients with decompensated chronic hepatitis B cirrhosis.Methods:From October 2007 to December 2019,100 patients with decompensated chronic hepatitis B cirrhosis who we... Objective:To explore the effect of entecavir on patients with decompensated chronic hepatitis B cirrhosis.Methods:From October 2007 to December 2019,100 patients with decompensated chronic hepatitis B cirrhosis who were treated in our hospital were selected to carry out this study.The clinical data of the patients were analyzed.According to whether entecavir treatment was carried out,100 patients were divided into two groups,50 cases in the control group and 50 cases in the observation group.The control group was treated with conventional drugs,and the observation group was treated with entecavir.Liver function indexes,liver fibrosis indexes,HBV-DNA negative conversion rate and incidence of adverse reactions were compared between the two groups.Results:Compared with the control group,the liver function indexes of the observation group were lower,P<0.05;Compared with the control group,the observation group was better,P<0.05;The negative rate of HBV-DNA in the observation group was lower than that in the control group(P<0.05);There was no difference in the incidence of adverse reactions between the two groups,P>0.05.Conclusion:Entecavir can not only improve the liver function,but also enhance the shortterm treatment effect,without increasing adverse reactions,and has high safety,which is worthy of recommendation. 展开更多
关键词 Decompensated stage of chronic hepatitis B cirrhosis ENTECAVIR Treatment effect negative rate of hbv-dna
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An early recognition algorithm for BitTorrent traffic based on improved K-means
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作者 荣辉桂 李明伟 蔡立军 《Journal of Central South University》 SCIE EI CAS 2011年第6期2061-2067,共7页
In response to the deficiencies of BitTorrent, the concept of density radius was proposed, and the distance from the maximum point of radius density to cluster center as a cluster radius was taken to solve the too lar... In response to the deficiencies of BitTorrent, the concept of density radius was proposed, and the distance from the maximum point of radius density to cluster center as a cluster radius was taken to solve the too large cluster radius resulted from the discrete points and to reduce the false positive rate of early recognition algorithms. Simulation results show that in the actual network environment, the improved algorithm, compared with K-means, will reduce the false positive rate of early identification algorithm from 6.3% to 0.9% and has a higher operational efficiency. 展开更多
关键词 traffic identification early recognition algorithm cluster radius false positive/negative rate
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The Effectiveness of the ECB Announcement Channel
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作者 Ahmed Hachicha Afif Masmoudi 《Applied Mathematics》 2014年第6期1029-1045,共17页
Empirical study on the factors that induce jumps in interest rates in the euro area is still missing. In this paper, maximum likelihood estimates of I-distribution parameters are extracted using as a first step, an or... Empirical study on the factors that induce jumps in interest rates in the euro area is still missing. In this paper, maximum likelihood estimates of I-distribution parameters are extracted using as a first step, an original linear model. According to the contribution of ([1] [2]) in the case of developing a class of Poisson-Gaussian model, we try to enhance the predictive power of this model by distinguishing between a pure Gaussian and Poisson-Gaussian distributions. Such an empirical tool permits to optimizing results through a comparative analysis dealing with the fluctuation of the Euro-interbank offered rate and its statistical descriptive behaviour. The analytical and empirical methods try to evaluate the behavioural success of the ECB intervention in setting interest rates for different maturities. Jumps in euribor interest rate can mainly be linked to surprise decisions of the European Central Bank, and the too frequent meetings of the ECB before November 2001. Despite this special event that leads to a certain lack of predictability, other few day-of-week effects are modelled to prove eventual evidence of bond market overreaction. Empirical results prove that Mondays and Wednesdays are the preponderant days. Regarding monetary policy, negative surprises induce larger jumps than positive ones. 展开更多
关键词 JUMPS Euribor INTEREST rates Poisson-Gaussian Model negative Surprises
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Modified Ramsey Rule, Optimal Carbon Tax and Economic Growth 被引量:1
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作者 Morio Kuninori Masayuki Otaki 《Atmospheric and Climate Sciences》 2016年第2期224-235,共12页
In contrast to the overlapping-generations model, it is allowable to discount the future utility in a dynasty model without the ethical difficulty related to intergenerational conflicts. Much precedent research uses R... In contrast to the overlapping-generations model, it is allowable to discount the future utility in a dynasty model without the ethical difficulty related to intergenerational conflicts. Much precedent research uses Ramsey-type optimal growth theory in order to estimate the social discount rate. However, one must note that almost all the formulations neglect the existence of negative intertemporal externalities. This problem is vital when one analyzes the global warming problem mainly caused by the excess concentration of carbon dioxide (CO<sub>2</sub>). This is because an adjoining effect of capital accumulation exists besides the improvement of product capacity, which is reflected in the rate of interest (or equivalently, the marginal productivity of capital). That is, one cannot neglect a negative externality to the future productivity that originates from the excess emissions of CO<sub>2</sub>. Accordingly, following the optimal growth theory, the effective social discount rate should be heightened by a proportional carbon tax to suppress future excess consumption/ emissions than in the case of the existing analyses, which exclude such an intertemporal external diseconomy. 展开更多
关键词 Modified Ramsey Rule Social Discount rate Optimal Carbon Tax negative Externality by the Emissions of CO2
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方法论批判视域中的“利润率下降规律之谜”
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作者 宁殿霞 《西安财经大学学报》 CSSCI 2021年第5期72-78,共7页
经济学对利润率下降规律的论证得出利润率的变动趋势迥异,已构成“利润率下降规律之谜”。其实,利润率下降规律不是因下降的结果而存在,而是因下降的趋势驱动历史的上升运动而存在,而且这种上升运动是一个“自然历史过程”。对这一规律... 经济学对利润率下降规律的论证得出利润率的变动趋势迥异,已构成“利润率下降规律之谜”。其实,利润率下降规律不是因下降的结果而存在,而是因下降的趋势驱动历史的上升运动而存在,而且这种上升运动是一个“自然历史过程”。对这一规律实证论证的结果无论是利润率上升还是下降,都陷入方法论的窠臼,因为通过计算得出的利润率与“利润率下降规律”中的利润率并不相同,这种计算方法遮蔽了与资本有机构成变动相统一的资本积累、生产力提高和资本内在否定性,这必然导致技术层面可计算的利润率上升亦或下降的不确定结果。构成这一迷局的关键不在于上升还是下降,而在于出发点上方法论的不同。 展开更多
关键词 利润率下降规律 资本有机构成 资本内在否定性 方法论批判
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64排螺旋CT冠脉成像效果与影响因素研究 被引量:7
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作者 李伟 陈雄钊 +3 位作者 兰勇 胡茂清 罗学毛 龙晚生 《国际生物医学工程杂志》 CAS 北大核心 2009年第5期267-272,共6页
目的 探讨64排螺旋CT冠脉成像中影响图像质量的各种因素及其影响程度以及评估冠脉狭窄的效果.方法 通过838例临床疑似冠心病患者的64排螺旋CT冠脉成像,并以其中218例在1周内进行的常规冠状动脉造影为标准,分析64排螺旋CT冠脉成像在评估... 目的 探讨64排螺旋CT冠脉成像中影响图像质量的各种因素及其影响程度以及评估冠脉狭窄的效果.方法 通过838例临床疑似冠心病患者的64排螺旋CT冠脉成像,并以其中218例在1周内进行的常规冠状动脉造影为标准,分析64排螺旋CT冠脉成像在评估冠脉狭窄的灵敏度、准确率、阳性预测值和阴性预测值.结果 心率、心率变化幅度、延迟时间设定、β受体阻滞剂、呼吸频率、屏气合作与否、造影剂注射总量与速度、图像重建时相、冠状动脉钙化、扫描参数、患者年龄性别、机器软硬件性能等是影响64排螺旋CT成像质量的因素.64排螺旋CT冠脉成像评估冠脉狭窄的准确率为95.9%,阳性与阴性预测值分别为92.3%、90.0%.结论 得到了影响64排螺旋CT冠脉成像的各种因素,分析了减少和消除这些因素影响的方法.在评估冠脉狭窄方面,64排螺旋CT冠脉成像基本能满足临床要求. 展开更多
关键词 螺旋 冠脉成像 成像效果 影响因素研究 spiral CT CORONARY artery influence factors 冠脉狭窄 image quality conventional CORONARY HEART disease 阴性预测值 HEART rate CORONARY angiography 评估 常规冠状动脉造影 positive negative contrast medium examination of
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Signed PageRank on Online Rating Systems 被引量:4
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作者 GU Ke FAN Ying DI Zengru 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2022年第1期58-80,共23页
The ratings in many user-object online rating systems can reflect whether users like or dislike the objects,and in some online rating systems,users can directly choose whether to like an object.So these systems can be... The ratings in many user-object online rating systems can reflect whether users like or dislike the objects,and in some online rating systems,users can directly choose whether to like an object.So these systems can be represented by signed bipartite networks,but the original unsigned node evaluation algorithm cannot be directly used on the signed networks.This paper proposes the Signed Page Rank algorithm for signed bipartite networks to evaluate the object and user nodes at the same time.Based on the global information,the nodes can be sorted by the Signed Page Rank values in descending order,and the result is SR Ranking.The authors analyze the characteristics of top and bottom nodes of the real networks and find out that for objects,the SR Ranking can provide a more reasonable ranking which combines the degree and rating of node,and the algorithm also can help us to identify users with specific rating patterns.By discussing the location of negative edges and the sensitivity of object SR Ranking to negative edges,the authors also explore that the negative edges play an important role in the algorithm and explain that why the bad reviews are more important in real networks. 展开更多
关键词 negative edges node evaluation online rating systems signed Page Rank
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