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Copyright of Large Electric Machine & Hydraulic Turbine is the property of Large Electric Machine & Hydraulic Turbine Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Agricultural Outlook (1673-3908) is the property of Institute of Agricultural Information, Chinese Academy of Agricultural Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Seasonal fluctuations play an important role in the pricing of a timber sale. A good understanding of timber price mechanisms and predictability in the timber market would be very practical for forest owners, managers, and investors, and is crucial for the correct functioning of the timber sector. This research aimed to analyze the effect of sale season on timber (sawlog and lumber) prices of high-value species groups (e.g., oriental beech, chestnut-leaved oak, common alder, velvet maple, and common hornbeam) in the Hyrcanian temperate forests (Northern Iran). The data were collected from official sale documents of the Azarroud Forestry Plan from 1992 to 2015. The relevant data of 592 sale lots at forest roadside were extracted into a data set. Then, the average timber prices (sawlog and lumber) per season/year in quarterly frequency were calculated. In doing so, two-time series of seasonal prices for the sawlog and lumber was obtained. The stationarity of the time series was statistically verified using the augmented Dickey–Fuller test. The effect of sale seasons on timber price was first analyzed using multiple linear regression analysis dummy variables. The results showed that autumn and summer have a significant positive effect on timber prices of 6.5% and 6.1%, respectively. Additionally, the decomposition of time series results showed that the highest prices of the sawlog and lumber were in quarter 3 and quarter 2, respectively, due to an increase in construction activities that picked up in the autumn season. Information about potential price fluctuations will be plausible and allow suppliers and users of sawlogs to adjust their supply and demand. This valuable information can be used in marketing and strategic forest management planning for Hyrcanian temperate forests and other temperate countries with similar conditions. [ABSTRACT FROM AUTHOR]

Abstract The mean-reverting nature of freight rates is one of the important subjects in maritime economics. The classic understanding of maritime economics (and that of the shipping industry) suggests that freight rate processes are mean-reverting and approach the level decided by the demand/supply ratio. However, statistical tests on freight rate processes often reveal these processes to be non-stationary, which means the processes would not have a mean-reverting nature. In this study, we investigated the mean-reverting nature of Panamax freight rates (Baltic Panamax 4 T/C Average) for two “means”: the actual freight rate process itself, and the deviation process of actual freight rates from estimated ones based on the demand/supply ratio. The AR (1) model can be applied to both processes, and their autoregressive coefficient φ was between 0 and 1. In the actual freight process, φ was close to 1, and a unit root test failed to reject that the process is non-stationary. By contrast, in the deviation process, φ was sufficiently smaller than 1, and a unit root test rejected that the process is non-stationary. The result can resolve the contradiction between two views on mean-reverting nature; if we focus on the actual freight rate process itself and do not consider demand/supply, the process is non-stationary and does not have a mean-reverting nature. If we focus on the deviation process of the actual freight rates from the level decided by the demand/supply ratio, the process is stationary and tends to approach zero.

In rural poverty governance, one of the most significant challenges faced by developing countries is to reduce the negative impact of economic growth fluctuations on poverty reduction, so as to achieve a win-win situation of "economic growth and poverty reduction". Based on the provincial-level panel data and data of poverty-stricken counties from 2000 to 2016 in China, this paper evaluates the poverty reduction effect of rural public expenditure from the perspectives of cyclical fluctuation and spatial spillover by using the instrumental variable method. It was found that rural public expenditure is pro-cyclical, and after exclusion of the cyclical factors, the essence of fluctuations is still pro-cyclical. Further research also shows that rural public expenditure has a significant spatial spillover effect on poverty reduction, which is even greater than the direct effect. Based on these findings, the policy implications can be that it is critical to provide moderate-scale and stable rural public expenditure, and establish a multi-level and differentiated agricultural insurance system supported by the government. This paper reveals the spatial interaction mechanism between public expenditure and poverty reduction, and also provides reference for correct evaluation of the economic growth and poverty reduction in developing countries. [ABSTRACT FROM AUTHOR]

Seasonal fluctuations play an important role in the pricing of a timber sale. A good understanding of timber price mechanisms and predictability in the timber market would be very practical for forest owners, managers, and investors, and is crucial for the correct functioning of the timber sector. This research aimed to analyze the effect of sale season on timber (sawlog and lumber) prices of high-value species groups (e.g., oriental beech, chestnut-leaved oak, common alder, velvet maple, and common hornbeam) in the Hyrcanian temperate forests (Northern Iran). The data were collected from official sale documents of the Azarroud Forestry Plan from 1992 to 2015. The relevant data of 592 sale lots at forest roadside were extracted into a data set. Then, the average timber prices (sawlog and lumber) per season/year in quarterly frequency were calculated. In doing so, two-time series of seasonal prices for the sawlog and lumber was obtained. The stationarity of the time series was statistically verified using the augmented Dickey–Fuller test. The effect of sale seasons on timber price was first analyzed using multiple linear regression analysis dummy variables. The results showed that autumn and summer have a significant positive effect on timber prices of 6.5% and 6.1%, respectively. Additionally, the decomposition of time series results showed that the highest prices of the sawlog and lumber were in quarter 3 and quarter 2, respectively, due to an increase in construction activities that picked up in the autumn season. Information about potential price fluctuations will be plausible and allow suppliers and users of sawlogs to adjust their supply and demand. This valuable information can be used in marketing and strategic forest management planning for Hyrcanian temperate forests and other temperate countries with similar conditions.

The mean-reverting nature of freight rates is one of the important subjects in maritime economics. The classic understanding of maritime economics (and that of the shipping industry) suggests that freight rate processes are mean-reverting and approach the level decided by the demand/supply ratio. However, statistical tests on freight rate processes often reveal these processes to be non-stationary, which means the processes would not have a mean-reverting nature. In this study, we investigated the mean-reverting nature of Panamax freight rates (Baltic Panamax 4 T/C Average) for two "means": the actual freight rate process itself, and the deviation process of actual freight rates from estimated ones based on the demand/supply ratio. The AR (1) model can be applied to both processes, and their autoregressive coefficient φ was between 0 and 1. In the actual freight process, φ was close to 1, and a unit root test failed to reject that the process is non-stationary. By contrast, in the deviation process, φ was sufficiently smaller than 1, and a unit root test rejected that the process is non-stationary. The result can resolve the contradiction between two views on mean-reverting nature; if we focus on the actual freight rate process itself and do not consider demand/supply, the process is non-stationary and does not have a mean-reverting nature. If we focus on the deviation process of the actual freight rates from the level decided by the demand/supply ratio, the process is stationary and tends to approach zero. [ABSTRACT FROM AUTHOR]

Although there are several mechanisms within theoretical models acknowledging that supply shocks can account for an important part of output fluctuations, even in the short-run, policy practitioners continue endorsing the idea that only demand shocks explain them. This article provides empirical evidence on several Latin American countries and the USA to show that the share of output variance explained by supply shocks in the short-run is substantial. It also offers a more agnostic implementation of the Blanchard-Quah type of structural analysis that focuses on policy evaluation. For this purpose, we propose constructing two indicators out of the historical decomposition of shocks: the goods market unbalance (GMU) and the total cyclical fluctuations (TCF). While GMU is an excess demand measurement that reveals the scope of the distortions caused by shocks, TCF, combined with GMU, helps to understand what type of shock is predominantly explaining (output and inflation) fluctuations. These two pieces of information provide a very different diagnosis than traditional output gaps and should guide monetary policy interventions more adequately. The agnosticism of this proposal has two aspects: the use of a different identification strategy and the assessment of the effects of both supply and demand shocks on output. [ABSTRACT FROM AUTHOR]

The objective of the study was to verify the applicability and usefulness of time series decomposition in analyzing the variability of timber prices and supply in Poland. The employed multiplicative model was the product of four components: cyclical, seasonal, and irregular fluctuations and the long-term trend. The elements of the time series were determined by means of the Census X11 method, while cyclicality was separated from the trend employing the Hodrick−Prescott filter. Data included quarterly information about the supply (volume) and prices (value) of the timber sold by the State Forests in the years 2005−2018. Analyses were performed for tree species with the greatest economic significance, that is, pine, oak, spruce, beech, birch, and alder, and for their most popular assortments: general purpose large-diameter timber (W0) and medium-diameter timber (S2A). Time series decomposition of quarterly timber production volume and prices revealed irregular, seasonal, and cyclic fluctuations. Within an annual time horizon, irregular fluctuations accounted on average for 6.7% and 28% of overall variability in timber prices and supply, respectively; they exhibited low amplitudes (+5%, −25%, respectively). Cyclical fluctuations were primarily found for prices and were characterized by substantial variations in cycle length (2−4 years) and change amplitude (3−27 Euros). Cyclical fluctuations in timber prices and supply were usually negatively correlated with each other: the upper turning points of price cycles fell near the lower turning points of supply cycles (with a shift of 1 to 3 quarters). The seasonality of prices was also inversely correlated with supply: quarters with low supply exhibited higher prices and vice versa. Seasonal fluctuations were more pronounced for timber supply (36%) as compared to timber prices (20.3%). Different seasonality patterns were found for hardwood and softwood. The lowest supply of softwood was found in the first quarter and the highest in the third quarter (spruce) or fourth quarter (pine). The supply of hardwood was the highest in the first quarter and the lowest in the third quarter.

The cyclical fluctuation phenomenon of the coalbed methane (CBM) production well is observed for the first time in Guqiao Coalfield.What causes this phenomenon and how prevents it,which have not been reported at home and abroad.The analysis of preventive measures and causes of cyclical fluctuation in coalbed methane wells production is of great significance for the efficient development of low permeability and soft broken seam.By the in-depth analysis of bottom hole pressure,the gas production and other production data of the coalbed methane wells,the cycle is divided into the stationary stage of production output (bottom hole flowing pressure),the declining stage of production output (bottom hole flowing pressure) and the increasing stage of production output (bottom hole flowing pressure).Based on gas line gathering,data acquisition instrument and coal reservoir,combined with the coal reservoir characteristics,reservoir stimulation and work over,it shows that the gas resistance effect which leads to the solid effect is the main cause of the production cyclical fluctuation phenomenon.Cyclical fluctuation characteristics occur,as the consequence of the blockade to fluid (water and gas) flow caused by the gas resistance effect and the solid resistance effect,which is also verified by numerical simulation method.Some suggestions are put forward to reduce the air resistance and solid resistance effect,including using the coal seam roof fracturing instead of directly coal seam fracturing,optimizing surface active agent,adopting drainage technique of hierarchical control pressure,and producing properly coal fines of propped fracture,etc. [ABSTRACT FROM AUTHOR]

Copyright of Transformations in Business & Economics is the property of Vilnius University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: There is a strong consistency between fluctuations in electricity demand and business cycle in macro-economy in China, and the former is stronger than the latter since 1991. The empirical study shows that the main reason for the cyclical fluctuations in electricity demand is the cyclical fluctuation in high energy consumption industries (HECI). Its transmission mechanism in terms of electricity demand is “Investment in the four HECI - HECI forming production capacities - Electricity consumption growths - Investment in electricity growth”. Therefore, in order to smooth cyclical fluctuation, it is necessary to strengthen the plan of investments in HECI and the investment in electricity industry itself. [Copyright &y& Elsevier]

The objective of the study was to verify the applicability and usefulness of time series decomposition in analyzing the variability of timber prices and supply in Poland. The employed multiplicative model was the product of four components: cyclical, seasonal, and irregular fluctuations and the long-term trend. The elements of the time series were determined by means of the Census X11 method, while cyclicality was separated from the trend employing the Hodrick–Prescott filter. Data included quarterly information about the supply (volume) and prices (value) of the timber sold by the State Forests in the years 2005–2018. Analyses were performed for tree species with the greatest economic significance, that is, pine, oak, spruce, beech, birch, and alder, and for their most popular assortments: general purpose large-diameter timber (W0) and medium-diameter timber (S2A). Time series decomposition of quarterly timber production volume and prices revealed irregular, seasonal, and cyclic fluctuations. Within an annual time horizon, irregular fluctuations accounted on average for 6.7% and 28% of overall variability in timber prices and supply, respectively; they exhibited low amplitudes (+5%, −25%, respectively). Cyclical fluctuations were primarily found for prices and were characterized by substantial variations in cycle length (2–4 years) and change amplitude (3–27 Euros). Cyclical fluctuations in timber prices and supply were usually negatively correlated with each other: the upper turning points of price cycles fell near the lower turning points of supply cycles (with a shift of 1 to 3 quarters). The seasonality of prices was also inversely correlated with supply: quarters with low supply exhibited higher prices and vice versa. Seasonal fluctuations were more pronounced for timber supply (36%) as compared to timber prices (20.3%). Different seasonality patterns were found for hardwood and softwood. The lowest supply of softwood was found in the first quarter and the highest in the third quarter (spruce) or fourth quarter (pine). The supply of hardwood was the highest in the first quarter and the lowest in the third quarter. [ABSTRACT FROM AUTHOR]

In the course of operation, the construction industry will repeat deviations and adjustments to it equilibrium state. Understanding the development fluctuations of the construction industry is critical to the formulation of a country's sustainable development strategy. The purpose of this paper is to investigate the development trend and fluctuation periodicity of the construction industry, particularly the deviation and characteristics of the development. In this paper, based on the H-P filtering method, the residual method for measurement of macro-economic cycle fluctuation is used to divide the periodic fluctuation of the Chinese construction industry into five rounds of economic cycles since the reform and opening up. The results are tested by a random test model and a self-correlation coefficient test model. The longitudinal time-series of data investigated in this research is the constant-price, gross output values of the construction industry in China in the period of 1980–2017 for a total of 38 years based on the national annual statistics. The results of the mathematical test show that the peak or valley of the economic cycle fluctuation of the construction industry in China reappears about every seven years or so. It shows that since the reform and opening up, the peak position of the cycle fluctuation of the Chinese construction industry began to decrease gradually, the valley level began to rise gradually, the volatility showed a downward trend, and the construction industry cycle fluctuation entered a steady and smooth process. The results of this study provide new comprehension of the development trend of construction industry and build the theoretical basis for governments and enterprises to judge the future development trends when formulating the relevant policies. [ABSTRACT FROM AUTHOR]