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PDMS项目阀门Commodity Code软件开发应用
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作者 邹培轩 《化工设计》 CAS 2023年第4期28-31,1,共5页
本文主要介绍利用PDMS内置PML编程语言进行阀门Commodity Code开发的思路及程序应用效果。
关键词 阀门 PDMS PML commodity CODE
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Price linkage between Chinese and international nonferrous metals commodity markets based on VAR-DCC-GARCH models 被引量:16
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作者 岳意定 刘笃池 徐珊 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第3期1020-1026,共7页
Using VAR-DCC-GARCH model,the literature on commodity price was extended by exploring the co-movement between Chinese nonferrous metal prices and global nonferrous metal prices represented by the nonferrous metal pric... Using VAR-DCC-GARCH model,the literature on commodity price was extended by exploring the co-movement between Chinese nonferrous metal prices and global nonferrous metal prices represented by the nonferrous metal prices from London Metal Exchange(LME).The results show that LME nonferrous metals prices still have a greater impact on Chinese nonferrous metals prices.However,the impact of Chinese nonferrous metals prices on LME nonferrous metals prices is still weak except for lead price.The co-movement of nonferrous metal prices between LME and China presents hysteretic nature,and it lasts for 7-8trading days.Furthermore,the co-movement between LME nonferrous metals prices and Chinese nonferrous metals prices has the characteristics of time-varying,and the correlation of lead prices between LME and China is the more stable than all other nonferrous metals prices. 展开更多
关键词 price linkage nonferrous metals commodity prices Chinese metals commodity market LME CO-MOVEMENT VAR model DCC-GARCH model
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From trash to treasure: Chemical recycling and upcycling of commodity plastic waste to fuels, high-valued chemicals and advanced materials 被引量:8
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作者 Fan Zhang Fang Wang +4 位作者 Xiangyue Wei Yang Yang Shimei Xu Dehui Deng Yu-Zhong Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第6期369-388,I0011,共21页
Of all the existing materials, plastics are no doubt among the most versatile ones. However, the extreme increases in plastic production as well as the difficulty of the material for degradation have led to a huge num... Of all the existing materials, plastics are no doubt among the most versatile ones. However, the extreme increases in plastic production as well as the difficulty of the material for degradation have led to a huge number of plastic wastes. Their recycling rate after disposal is less than 10%, resulting in a series of serious environmental and ecological problems as well as a significant waste of resources. Current recycling methods generally suffer from large energy consumption, the low utilization rate of recycled products with low added value, and produce other waste during the process. Here, we summarized recentlydeveloped chemical recycling ways on commodity plastics, especially new catalytic paths in production of fuels, high-valued chemicals and advanced materials from a single virgin or a mixture of plastic waste,which have emerged as promising ways to valorize waste plastics more economically and environmentally friendly. The new catalyst design criteria as well as innovative catalytic paths and technologies for plastic upcycling are highlighted. Beyond energy recovery by incineration, these approaches demonstrate how waste plastics can be a viable feedstock for energy use with the generation of clean H_(2), high-quality liquid fuels and materials for energy storage, and help inspiring more catalytic process on plastic upcycling to overcome the economical hurdle and building a circular plastic economy. 展开更多
关键词 Chemical recycling Upcycling commodity plastic Sustainable development Catalytic path
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City Networks of Online Commodity Services in China:Empirical Analysis of Tmall Clothing and Electronic Retailers 被引量:7
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作者 XI Guangliang ZHEN Feng +1 位作者 HE Jinliao GONG Yanhao 《Chinese Geographical Science》 SCIE CSCD 2018年第2期231-246,共16页
City networks have been a critical topic in the fields of urban geography and regional economics. Numerous studies have explored city networks, focusing mainly on infrastructure and industrial networks. Unlike traditi... City networks have been a critical topic in the fields of urban geography and regional economics. Numerous studies have explored city networks, focusing mainly on infrastructure and industrial networks. Unlike traditional urban network of which the major measuring indexes are population sizes and entity industries, online commodity service networks could reflect well the influencing of emerging economies, especially the Internet economy, on city networks. This study analyzes and reveals structural features of China's city networks through online commodity services, providing the internet economic approach on city networks. Results indicate that the core cities of online commodity service networks are mainly concentrated in eastern coastal areas. In addition, spatial polarization and layer structure of network connections are obvious, descending from the centers in eastern China to peripheral cities in central and western China. Online commodity services of different cities show apparent differences and uncertainties in terms of specialization rates of international connection, which presents a tendency toward diversification. Online commodity service networks are not only associated with goods production, supply, and consumption in physical space but also reflect virtual information, capital, and technology flows, thus providing a new empirical approach for understanding city networks in information and internet economic age. 展开更多
关键词 city networks online commodity services intercity relationships SPECIALIZATION
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Alternative techniques for forecasting mineral commodity prices 被引量:1
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作者 C.A.Tapia Cortez S.Saydam +1 位作者 J.Coulton C.Sammut 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2018年第2期309-322,共14页
Forecasting mineral commodity(MC) prices has been an important and difficult task traditionally addressed by econometric, stochastic-Gaussian and time series techniques. None of these techniques has proved suitable to... Forecasting mineral commodity(MC) prices has been an important and difficult task traditionally addressed by econometric, stochastic-Gaussian and time series techniques. None of these techniques has proved suitable to represent the dynamic behavior and time related nature of MC markets. Chaos theory(CT) and machine learning(ML) techniques are able to represent the temporal relationships of variables and their evolution has been used separately to better understand and represent MC markets. CT can determine a system's dynamics in the form of time delay and embedding dimension. However, this information has often been solely used to describe the system's behavior and not for forecasting.Compared to traditional techniques, ML has better performance for forecasting MC prices, due to its capacity for finding patterns governing the system's dynamics. However, the rational nature of economic problems increases concerns regarding the use of hidden patterns for forecasting. Therefore, it is uncertain if variables selected and hidden patterns found by ML can represent the economic rationality.Despite their refined features for representing system dynamics, the separate use of either CT or ML does not provide the expected realistic accuracy. By itself, neither CT nor ML are able to identify the main variables affecting systems, recognize the relation and influence of variables though time, and discover hidden patterns governing systems evolution simultaneously. This paper discusses the necessity to adapt and combine CT and ML to obtain a more realistic representation of MC market behavior to forecast long-term price trends. 展开更多
关键词 PRICE forecasting MINERAL commodity MARKET dynamics CHAOS theory Machine learning
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Evaluation of the impact of commodity price change on mine plan of underground mining 被引量:2
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作者 Salama Abubakary Nehring Micah Greberg Jenny 《International Journal of Mining Science and Technology》 CSCD 2015年第3期375-382,共8页
Fluctuations in commodity prices should influence mining operations to continually update and adjust their mine plans in order to capture additional value under new market conditions. One of the adjustments is the cha... Fluctuations in commodity prices should influence mining operations to continually update and adjust their mine plans in order to capture additional value under new market conditions. One of the adjustments is the change in production sequencing. This paper seeks to present a method for quantifying the net present value(NPV) that may be directly attributed to the change in commodity prices. The evaluation is conducted across ten copper price scenarios. Discrete event simulation combined with mixed integer programming was used to attain a viable production strategy and to generate optimal mine plans. The analysis indicates that an increase in prices results in an increased in the NPV from$96.57M to $755.65M. In an environment where mining operations must be striving to gain as much value as possible from the rights to exploit a finite resource, it is not appropriate to keep operating under the same mine plan if commodity prices alter during the course of operations. 展开更多
关键词 Mine planning Underground mining commodity price Discrete event simulation Mixed integer programming
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Strategic Agricultural Commodity Value Chains in Africa for Increased Food: The Regional Approach for Food Security 被引量:1
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作者 Mahamadou Nassirou Ba 《Agricultural Sciences》 2016年第9期549-585,共37页
The challenge Africa faces the most is how to feed the 2.4 billion people in 2050. This will require a transformational agriculture. Africa doesn’t need subsistence agriculture, but rather agriculture linked to the m... The challenge Africa faces the most is how to feed the 2.4 billion people in 2050. This will require a transformational agriculture. Africa doesn’t need subsistence agriculture, but rather agriculture linked to the market where market demand and the consuming habits are taken in consideration. Agriculture evolves in an environment where small holders are linked to markets (national and regional), where economies of complementarity and economies of scale are taken advantage of by producers and private sector. In short, Africa will need a paradigm shift to industrialise and commercialise its agriculture sector in order to increase food production, and income and to create jobs in and outside the sector. Africa needs agribusiness and agro-industries to domesticate the benefits of the sector, to create wealth in the sector and retain that wealth in the continent. Agricultural commodities regional value chains for increased food should be the target for Africa. The continent remains the region with the highest prevalence of under-nourishment. Since agriculture remains the mainstay of most African economies except the mineral producers, the sector deserves a close attention from leaders. It accounts for 65% of employment and 40% of Africa’s export earnings and accounts for 17% of the GDP. This shows how important the sector is. Agriculture needs to be seen as a conduit for farmers to get connected to markets, a conduit for revenue, for jobs and for transformation. Africa needs to come back on the international scene as food sufficient continent and even food exporter. This can be achieved only with a stable, productive agricultural resource base. Thus, achieving and sustaining food security and economic prosperity in Africa will require significant efforts to modernize the continent’s agriculture sector through injection of agribusiness and agro-industries and through the application of science and technology in agriculture. In essence, agriculture needs to be viewed as knowledge based entrepreneurial activity. Smart investments in agriculture will have multiplier effects for the whole economy and hence induce prosperity to other sectors. In recent years, a renewed focus on agriculture has been evident in policy and development agendas across the African continent. This paper outlines the status of agriculture, agribusiness and agro-industries in Africa, their role in the agenda of agricultural transformation and economic transformation and the focus on regional value chain to increase food production, transformation and trade. The paper adopts a new thinking in agriculture, which reflects a regional value chain approach. The author covers such issues as: need for agricultural transformation, the role of value chain in agricultural sector, the need for regional value chain for increased income and increased food, the role of markets and the common denominator of all, the regional integration to push forward the African agriculture agenda. Evidence shows that it is agricultural growth, through its leverage effects on the rest of the economy that typically enables poor countries, poor regions and ultimately poor households to take the first steps toward economic transformation. Therefore agricultural productivity, at the small holder’s level, has the potential to lift millions of Africa’s vulnerable out of poverty and provide sustainable jobs. Other factors, namely “the rapid urbanization” and “increased population growth”, are quoted to be of critical importance. Africa population is projected to double, attaining the 2.3 billion people mark over the next 40 years representing half of the globe’s total population. This could trigger competition for resources and can have devastating effects on natural resources if not rightly channelled. 展开更多
关键词 Food Security Agricultural commodities Value Chain Regional Value Chains Agricultural Transformation Agribusiness Agro-Industries
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Approaches for Making High Performance Polymer Materials from Commodity Polymers 被引量:2
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作者 Xu Xi The State Key Lab. of Polymer Materials Engineering of China, Polymer Research Institute of Sichuan University (Chengdu 610065, China) Research Institute of Polymer Materials of Shanghai Jiao Tong University (Shanghai 200240, China) 《合成化学》 CAS CSCD 2004年第z1期4-4,共1页
关键词 Approaches for Making High Performance Polymer Materials from commodity Polymers
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Research on the Development of Rural Commodity Economy in the Edo Period
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作者 Lei YE Lulu QIAN 《Asian Agricultural Research》 2014年第12期1-3,8,共4页
The rural commodity economy in the Edo period developed by leaps and bounds under the influence of institution,policy,technology and other factors. From the mid 17 th century,the specific area of cash crops gradually ... The rural commodity economy in the Edo period developed by leaps and bounds under the influence of institution,policy,technology and other factors. From the mid 17 th century,the specific area of cash crops gradually took shape in Japan and the largescale cultivation of cash crops greatly promoted the development of rural handicrafts,thereby creating the conditions for the initiation of the capitalist relations of production. The development of rural commodity economy not only changed the traditional mode of operation and production of Japanese farmers,but also accelerated the class differentiation,shook and disintegrated the economic foundation and class basis of Bakuhan society,and created the preconditions for the later Meiji Restoration. 展开更多
关键词 EDO PERIOD RURAL commodity ECONOMY Development CON
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Fractal and Fractional Diffusion Equations of Price Changing of Commodity
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作者 Tianquan Yun 《Applied Mathematics》 2013年第7期18-22,共5页
In this paper, three types of modeling of diffusion equations for price changing of commodity are studied. In which, the partial derivatives of price of commodity respected to time on the left hand side are integer-de... In this paper, three types of modeling of diffusion equations for price changing of commodity are studied. In which, the partial derivatives of price of commodity respected to time on the left hand side are integer-derivative, fractal derivative, and fractional derivative respectively;while just a second order derivative respected to space is considered on the right hand side. The solutions of these diffusion equations are obtained by method of departing variables and initial boundary conditions, by translation of variables, and by translation of operators. The definitions of order of commodity x and the distance between commodity?xi and xj are defined as [1]. Examples of calculation of price of pork, beef and mutton mainly due to price raising of pork in 2007-07 to 2008-02 inChina are given with same market data as [1]. Conclusion is made. 展开更多
关键词 FRACTAL DERIVATIVE FRACTIONAL DERIVATIVE Heat Diffusion Equation: Order of commodity Time-Space Exchange
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Structural Upgrade of China's Commodity Trade during 1987-2014
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作者 Liu Zuanshi Zhang Juan 《China Economist》 2018年第5期99-115,共17页
This paper investigates the structural upgrade of China's commodity trade over the past two decades from the perspectives of commodity categories, technical value-added and quality level. Based on the analysis of ... This paper investigates the structural upgrade of China's commodity trade over the past two decades from the perspectives of commodity categories, technical value-added and quality level. Based on the analysis of commodity categories, technical value-added and quality, this paper arrives at the following findings: High technology manufactures accounted for a growing share of China's commodity export, the overall technical level of Chinese exports significantly upgraded, and most of Chinese commodities upgraded from low quality to medium-and high-quality levels. As can be seen from the structure of China's bilateral trade with its five major trading partners, China's exporting goods remained inferior to importing goods in terms of technology and quality despite their quality upgrades. 展开更多
关键词 TRADE structure commodity CATEGORIES TECHNICAL LEVEL quality LEVEL
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Comprehensive Evaluation on the Regional Economy of Commodity Grain Base in Heilongjiang Province Based on Factor Analysis Method
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作者 SHEN Lei-ming XU Mei +1 位作者 WANG Fu-lin ZHANG Hao 《Asian Agricultural Research》 2010年第6期25-28,共4页
Taking a total of 13 areas in Heilongjiang commodity grain base as the research objects,9 indices are selected,which are regional GDP(X1),per capita GDP(X2),total value of tertiary industry(X3),financial revenue(X4),u... Taking a total of 13 areas in Heilongjiang commodity grain base as the research objects,9 indices are selected,which are regional GDP(X1),per capita GDP(X2),total value of tertiary industry(X3),financial revenue(X4),urban fixed assets investment(X5),average salary(X6),gross industrial output value(X7),total output value of farming,forestry,husbandry and fishing(X8),and retail sales of social consumer goods(X9).Based on this,evaluation index system of regional economy is established.According to the 2006-2008 Heilongjiang Statistical Yearbook,average values within 3 years are used as analytical data.Factor Analysis Method is adopted to establish regression model and to carry out comprehensive analysis.Result shows that Heilongjiang commodity grain base has extremely uneven regional economic development in different areas.According to the score order and actual situation,the 13 areas are divided into 4 types.The first and second types are Harbin and Daqing,respectively.The third type is Qiqihaer,Suihua,Mudanjiang and Jiamusi.And the forth type is Jixi,Shuangyashan,Heihe,Yichun,Qitaihe,Hegang and Daxinganling.Suggestions for the development of these areas are put forward. 展开更多
关键词 Heilongjiang commodity grain base Factor Analysis Method Regional economy Comprehensive evaluation China
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Tourism Commodity Industry Embraces Golden Period
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作者 Diana Liang 《China's Foreign Trade》 2017年第6期44-45,共2页
The tourism commodity industry has entered a golden period of development since Chinese government decided to raise the proportion of tourism shopping in tourism income in 2009.
关键词 Tourism commodity Industry Embraces Golden Period
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Measuring Criticality of Raw Materials: An Empirical Approach Assessing the Supply Risk Dimension of Commodity Criticality
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作者 Herbert Mayer Benedikt Gleich 《Natural Resources》 2015年第1期56-78,共23页
Providing a sustainable and reliable supply of raw materials at economic prices has become essential to industrialized economies. Therefore, the need for both economical and sustainable methods and strategies for the ... Providing a sustainable and reliable supply of raw materials at economic prices has become essential to industrialized economies. Therefore, the need for both economical and sustainable methods and strategies for the management of raw materials has been postulated to enable companies and economies to counteract dramatic effects of supply disruptions, or at least to provide early warnings. The relevant studies assign generic weights to different driving factors and therefrom derive criticality indexes. However, it often remains open how to interpret the resulting measures and how to apply them practically. Here we show that based on current commodity key figures, it is possible to empirically determine the risk for future price increases and fluctuations. Thus, we can identify future supply risks and incorporate their patterns into an empirically calibrated criticality measurement. To this end, we apply the well-known compounding framework used by many companies for their financial planning, calculating net present values and volatility from the predicted future price development. To calibrate each resource specific model, we perform extended regression analyses on our compounded criticality index from time series of 42 (out of about 60 industrially relevant) chemical elements. The analysis thereby covers 9 driving factors for criticality and a 40-year time span. Our results suggest a fundamental modification of current practices for criticality assessment, in particular by scaling the criticality measure to correspond with the net present value of future commodity expenses and future volatility. 展开更多
关键词 RAW Materials CRITICALITY Assessment commodity CRITICALITY CRITICALITY Index
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Evaluating the exchange rate and commodity price nexus in Malaysia: evidence from the threshold cointegration approach
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作者 Shamaila Butt Suresh Ramakrishnan +1 位作者 Nanthakumar Loganathan Muhammad Ali Chohan 《Financial Innovation》 2020年第1期392-410,共19页
This paper examines the long-and short-run dynamics of asymmetric adjustment between the nominal exchange rate and commodity prices,namely oil,palm oil,rubber,and natural gas prices,in Malaysia using monthly data from... This paper examines the long-and short-run dynamics of asymmetric adjustment between the nominal exchange rate and commodity prices,namely oil,palm oil,rubber,and natural gas prices,in Malaysia using monthly data from January 1994 to December 2017.The relationship between exchange rate and each commodity price is examined in terms of Engle-Granger and threshold cointegrations.The estimated results provide evidence of long-run threshold cointegration and show that the adjustments towards the long-run equilibrium position are asymmetric in the short run.Furthermore,this study finds evidence of a unidirectional causal relationship running from the nominal exchange rate to oil price in the long and short run using a spectral frequency domain causality application.There is also empirical evidence of bidirectional causality between the nominal exchange rate and palm oil price,rubber price,and natural gas price in the long and short run.Overall,the findings have significant implications for the current debate on the future of primary commodities in Malaysia. 展开更多
关键词 commodity prices Exchange rate Threshold cointegration
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Co‑movement of commodity price indexes and energy price index:a wavelet coherence approach
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作者 Dervis Kirikkaleli Hasan Gügö 《Financial Innovation》 2021年第1期323-340,共18页
This research sheds light on the causal link between commodity price indexes,i.e.,the Agricultural Raw Materials Price Index,Industry Input Price Index,Metal Price Index,and Energy Price Index,in the global market,usi... This research sheds light on the causal link between commodity price indexes,i.e.,the Agricultural Raw Materials Price Index,Industry Input Price Index,Metal Price Index,and Energy Price Index,in the global market,using wavelet coherence,Toda–Yamamoto causality,and gradual shift causality tests over the period 1992M1 to 2019M12.Findings from the wavelet power spectrum and partial wavelet coherence reveal that:(1)there was significant volatility in the Agricultural Raw Materials Price Index,Industry Input Price Index,Metal Price Index,and Energy Price Index between 2004 and 2014 at different frequencies;and(2)commodity price indexes significantly caused the energy price index at different time periods and frequencies.It is noteworthy that the outcomes of the Toda–Yamamoto causality and gradual-shift causality tests are in line with the results of wavelet coherence. 展开更多
关键词 Energy price commodity price Wavelet coherence CAUSALITY
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The volatility of returns from commodity futures:evidence from India
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作者 Isita Mukherjee Bhaskar Goswami 《Financial Innovation》 2017年第1期189-211,共23页
Background:This paper examines the pattern of the volatility of the daily return of select commodity futures in India and explores the extent to which the select commodity futures satisfy the Samuelson hypothesis.Meth... Background:This paper examines the pattern of the volatility of the daily return of select commodity futures in India and explores the extent to which the select commodity futures satisfy the Samuelson hypothesis.Methods:One commodity future from each group of futures is chosen for the analysis.The select commodities are potato,gold,crude oil,and mentha oil.The data are collected from MCX India over the period 2004–2012.This study uses several econometric techniques for the analysis.The GARCH model is introduced for examining the volatility of commodity futures.One of the key contributions of the paper is the use of theβterm of the GARCH model to address the Samuelson hypothesis.Result:The Samuelson hypothesis,when tested by daily returns and using standard deviation as a crude measure of volatility,is supported for gold futures only,as per the value ofβ(the GARCH effect).The values of the rolling standard deviation,used as a measure of the trend in the volatility of daily returns,exhibits a decreasing volatility trend for potato futures and an increasing volatility trend for gold futures in all contract cycles.The result of the GARCH(1,1)model suggests the presence of persistent volatility and the prevalence of long memory for the select commodity futures,except potato futures.Conclusions:The study sheds light on significant characteristics of the daily return volatility of the commodity futures under analysis.The results suggest the existence of a developed market for the gold and crude oil futures(with volatility clustering)and show that the maturity effect is only valid for the gold futures. 展开更多
关键词 commodity futures Daily return VOLATILITY Samuelson hypothesis GARCH
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Chinese Commodity Website Launches Logistics Integration Project
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作者 Zhu Zijun 《China's Foreign Trade》 2014年第Z2期33-33,共1页
Yiwubuy,the website of the world’s biggest small commodity market,has launched a logistics integration project,general manager Wang Jianjun announced on October 21 in Yiwu City in east China’s Zhejiang Province.The ... Yiwubuy,the website of the world’s biggest small commodity market,has launched a logistics integration project,general manager Wang Jianjun announced on October 21 in Yiwu City in east China’s Zhejiang Province.The project,named Logistics Through Train,aims to integrate logistics information resource and build a logistics platform at the Yiwu market so as to provide professional logistics 展开更多
关键词 LOGISTICS PROFESSIONAL commodity MANAGER COMPANIES
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Commodity Market and Financial Derivative Instruments: Is There a Cointegration?
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作者 Maria Leone Alberto Manelli Roberta Pace 《Journal of Modern Accounting and Auditing》 2019年第4期185-203,共19页
Over the past decade, agricultural commodity prices underwent wild swings, Periods of high growth in 2008 were followed by periods of sudden decrease in 2009, The excessive increase in food price volatility is a subje... Over the past decade, agricultural commodity prices underwent wild swings, Periods of high growth in 2008 were followed by periods of sudden decrease in 2009, The excessive increase in food price volatility is a subject of great interest because it has to do with the survival of mankind, Recent academic studies and policy makers have reached sharply different conclusions about the dynamics of such fluctuations, Also, some of them have indicated the main cause in speculative transactions and in the little regulation of futures markets, This paper intends to verify if there exists a co-implication between wheat futures price and some financial “speculative” variables, The results of cointegration analysis show that there is no evidence that financial derivative instruments determine the fluctuations of wheat futures price. 展开更多
关键词 FINANCIAL MARKET commodity MARKET SPECULATION GARCH model
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Dynamics of price cooperating model in commodity market
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作者 HE Meng-xing CUI Cheng 《Journal of Modern Accounting and Auditing》 2008年第10期12-17,共6页
For the problem of price fluctuation in the commodity market, some ordinary differential equation models are proposed and the stability of equilibrium price is studied. In this paper, we develop a mathematic model for... For the problem of price fluctuation in the commodity market, some ordinary differential equation models are proposed and the stability of equilibrium price is studied. In this paper, we develop a mathematic model for price cooperation with diffusion and lag. When the economic parameters satisfy some conditions, the existence and stability of periodic price are investigated. 展开更多
关键词 periodic price STABILITY commodity market
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