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Copyright of Natural Gas Industry is the property of Natural Gas Industry Journal Agency 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 Natural Gas Geoscience is the property of Natural Gas Geoscience 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 Natural Gas Industry is the property of Natural Gas Industry Journal Agency 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 Natural Gas Industry is the property of Natural Gas Industry Journal Agency 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 Acta Agriculturae Zhejiangensis is the property of Acta Agriculturae Zhejiangensis 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 Computer Measurement & Control is the property of Magazine Agency of Computer Measurement & Control 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.)

Objectives To meet the use requirements of a steam-powered system in different working conditions, it is necessary to study the design of the condensate water distribution and pipeline optimization.MethodsUsing the Flowmaster software, a simulation model of a ship's condensate water system was created. The pressure and flow rate in the condensate water system were studied in different working conditions of the steam-powered system. Based on this, two optimal design suggestions, reducing the installation height of the water tank and adjusting the system pipeline connection, were presented.ResultsThe calculation results showed that the maximum storage capacity is 0.128 (normalization result) when the openings of the throttle valve and circulation valve are 30% and 45% respectively, in reduced working conditions. Moreover, when the throttle valve opening is less than 13%, the condensate water system will not be able to store water. The maximum storage capacity was 0.404 (normalization result) when the openings of the throttle valve and the circulation valve were 90% and 18% respectively, in increased working conditions. The distribution coordination of the system was also better. Two optimization designs can effectively improve the condensate water distribution in reduced working conditions.ConclusionsThe research results can provide a reference for the optimal design of the actual ship's condensate water system.

With the change of edible oil consumption pattern from bulk to packing oil and the development of logistics industry, the construction of small and medium-sized edible oil packing plant is developing rapidly, due to the packaging plant's geographical location, processing scale, product types, goods turnover rate and logistics conditions are different, the design of the warehousing scheme is also different. By analyzing all relevant factors affecting the storage capacity and combining with the inherent characteristics of building workshop design, discusses the design parameter input conditions, reveals the general rules that can guide the design application, and constructs the theoretical calculation model of minimum storage capacity under specific conditions. Based on the superposition of the model with the common variables that are constantly changing in the actual production operation, the deviation of the real state from the theoretical model is corrected by introducing the turnover rate, and then a simple formula is derived to provide a reference for the design.

Due to the completion of the cascade reservoirs,the hydrological process of the basin has changed significantly,and the scheduling of the existing reservoirs has changed.The assessment of the regulation capacity of the existing reservoirs will help to re-define the role of the reservoirs in the runoff regulation.Taking Menkantan hydropower station and Datankou reservoir on Modaoxi Basin as examples,this paper proposes the concept of “virtual regulating storage”,and constructs a cascade POA optimal scheduling model to verify the regulation capacity of small hydropower stations.According to the calculated results,the amount of discarded water is reduced compared to that in the original operation mode,and the downstream reservoir's ability to regulate incoming water is effectively improved.The research results provide a reference for the verification of reservoir regulation capacity,and a mode to improve the power generation efficiency of small hydropower stations.

The natural storage capacity of the regulation and storage reservoir of CCS Hydropower Station in Ecuador is limited. According to the operation demand of the power station, in order to meet the requirements of daily regulation of the regulating reservoir, it is necessary to excavate the reservoir basin to increase the sufficient storage capacity. Under the condition of increasing a certain storage capacity, the mini- mum excavation volume is the goal and key point of design optimization. The excavation design of reservoir basin of CCS Hydropower Station in Ecuador is a trial and error process. In order to improve the calculation accuracy and design efficiency, BIM technology was used to build a parameterized three-dimensional model of storage capacity increment and excavation, and the optimal excavation scheme was given under the premise of ensuring the storage capacity, which was of great practical significance for the project implementation. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Henan University of Technology Natural Science Edition is the property of Henan University of Technology Journal Editorial Department 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 Natural Gas Industry is the property of Natural Gas Industry Journal Agency 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.)

A novel design of FR (fractional repetition) codes was proposed which aims at providing efficient repair at the minimum bandwidth regenerating point.The design consisted of an outer MDS (maximum distance separable) code and an inner repetition code,called GDDBFR (group divisible design based FR) codes.The proposed codes can achieve the system storage capacity under the random access model and are available for a wide range of parameters.Despite of the table-based repair,theoretical analysis identifies that GDDBFR codes generally have large node repair alternatives.Furthermore,experimental results show that GDDBFR codes can significantly reduce the failure repair time when compared with legacy RS (Reed-Solomon) codes and regenerating codes in the domain.

Watershed storage capacity (Wm) is an important basis for the classification of dry or wet soil in the calculation of mountain flash flood warning index of small watershed in hilly regions. Based on the three major hydrological regions in Shandong hydrological atlas, the storage capacities of the three major hydrological regions (hereafter refer to as regional storage capacity) have 3 different values. Because of the larger area of major hydrological region and the small area (generally 20 km2) of small watershed in hilly region for mountain flash flood warning, there may exists a large difference between regional storage capacity and the storage capacity of a small watershed in hilly region. In addition, the regional storage capacity was calculated based on hydrological and meteorological data in different regions before 1975. In the past 40 years, the underlying surface conditions of regions have changed greatly, and the regional storage capacity may have also changed accordingly. Therefore, in order to determine storage capacity of small watershed more precisely in the semi-arid and semi-humid northern region, especially in the hilly region that either lack data or no hydrological data, the SCS-CN model was used to determine storage capacity of the watershed with about 20 km2. Taking Zhudonghe watershed as an example, 6 rainfall events (with large rainfall, long duration and high flow) and runoffs from 1990 to 2008 were selected, and simulated by SCS-CN model, through which 6 CN numbers of each subbasin of Zhudonghe watershed were determined which were 116.49, 90.53, 84.57 121.48, 111.34, 94.95 and 76.52 mm, respectively. The average storage capacity of Zhudonghe watershed was obtained by the method of area weighting. The storage capacity of Zhudonghe watershed was 95.82 mm. To test the reliability of this SCS-CN method, the methods of measured rainfall runoff analysis and SCS formula are used and obtained the average storage capacity of Zhudonghe watershed that was 88.97 mm and 98.98 mm respectively. The relative difference between SCS-CN model and above two methods to determine the Wm was 7.7% and -3.2%, respectively. Therefore, comprehensive analysis of three methods, SCS-CN model to determine the watershed storage capacity is more reasonable and feasible. The SCS-CN model here provides a new way to determine the storage capacity of small watershed with data shortage in hilly regions, and provides a technical support for accurate mountain flash flood warning in small watershed. [ABSTRACT FROM AUTHOR]

Copyright of Natural Gas Geoscience is the property of Natural Gas Geoscience 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.)

The utilization of underground goaf for water preservation and the underground reservoir technology for water recycling are the effective measures to achieve a water-preserved mining in western mining area of China. It is crucial for the safe and efficient implement of underground reservoir technology to research and ascertain the rational water storage capacity in the goaf. The key issues，such as the calculation of water storage capacity，the maximum and rational capacity of underground reservoir，have been investigated by theoretical analysis，stimulation experiment and field observation. It shows that the water storage capacity of underground reservoir is the summation of void content of broken rock blocks in the overlying strata caving zone and the bed separation space of broken rock strata in the fissure zone within the water storage scope. The formula for calculating the void content of rock blocks in caving zone，which considers the coal seam dip angle，has been deduced based on the shape model resembling the parabolic body in the overlying strata caving zone. By utilizing the “O-shape circle” theory，the determination method of calculating the bed separation space under each key stratum and the broken rock strata between two key strata has been obtained. Thereby，according to the different locations of stored water level in overlying strata caving zone，the arithmetic expression for calculating water storage capacity in underground reservoir has been established，and the determination method of the maximum and rational capacity of underground reservoir has also been obtained. The capability of theoretical outcomes have been demonstrated by the practice of underground reservoir in Lijiahao coal mine. [ABSTRACT FROM AUTHOR]

Moisture storage capacity at root zone plays an important role in hydrological processes, soil moisture movement and vegetation development, which is also a crucial parameter in hydrological and ecological modelling. However, due to the great heterogeneity in soil texture and the restriction of observation currently, there is no effective way to observe this parameter at catchment scales. In this study, a typical catchment of the Taizi River in Northeast China was selected as the study area. On the basis of monthly runoff depth data at Nandianyu Hydrological Station, the parameters in FLEX model were calibrated and validated during different time periods, of which the parameter Su represents the moisture storage capacity at root zone, while the SuMax corresponds to the Su under the best hydrological process condition in simulation. A snow model was incorporated in the original FLEX hydrological model in order to improve the performance of the model in the places where snow and melting water cannot be ignored. Based on observational meteorology data and multi-source remote sensing data sets, the modified mass curve technique (MCT) was employed to estimate the moisture storage capacity at root zone in Nandianyu catchment, taking snowmelt as an important part of water input for technique modification. The MCT was originally used in engineering design, however, in this study the moisture storage capacity was estimated using this approach by treating the whole root zone of this catchment as a reservoir. Based on the relationship between cumulative inflow and water demand in dry seasons when the rate of water demand exceeded water inflow, the required moisture storage capacity at root zone for each year was yielded, and cross validated with the result derived from the FLEX model to test the availability of MCT in the study area. Different climate scenarios were further set to test the sensitivity of moisture storage capacity at root zone to rainfall, snowmelt and evapotranspiration when these 3 climate factors increased or reduced by 10%, 20% and 30% independently using the MCT which demonstrated to be feasible. The results show that: 1) The improved FLEX model could be used to simulate hydrological process in the study area, presenting a high accuracy in runoff depth simulation and flow hydrograph simulation. The value of parameter SuMax representing the moisture storage capacity at root zone under the best simulating condition was 27 mm; 2) The moisture storage capacity at root zone estimated by MCT was demonstrated to follow the Gumbel distribution, with a range of 21-84 mm. The value of moisture storage capacity derived from this approach coincided with the estimate derived from the FLEX model, which meant that the modified MCT could be used to estimate the moisture storage capacity at root zone in the study area, and the estimates derived from this approach could be used as parameters in hydrological and ecological models; 3) Curve slopes of the change of moisture storage capacity at root zone with evapotranspiration, precipitation and snowmelt were 1.37, 0.73 and 0.37, showing that the moisture storage capacity at root zone had a reduced sensitivity to the change of evapotranspiration, precipitation and snowmelt. Besides, with the increase of evapotranspiration and reduction of precipitation, the sensitivity of the moisture storage capacity at root zone enhanced while there was no big difference under the variations of snowmelt. This work can provide a basis for water deficit estimation and maintaining normal development of ecosystems when they are faced with drought. [ABSTRACT FROM AUTHOR]

The capacity expansion of underground gas storage in water flooding sandstone gas reservoir form can be realized through water flooding. But influenced by the reservoir heterogeneity and water invasion, the storage capacity and the working gas volume is mostly less than the designed value during the actual operation process. In order to optimize the injection production effect of gas storage, multirounds long core water-gas mutual flooding experiments were carried out to analyze the pressure field distribution and capacity utilization characteristics during the process, and to study the factors that affect the expansion. The study shows that with the more rounds of injection, gas displacement becomes more difficult, and the displacement result gradually becomes poorer, tending to the maximum storage capacity. The reservoirs located in far well area cannot effectively participate in storage operation. The storage equilibrium pressure is less than the upper limit pressure after the injection; and it is more than the lower limit pressure after gas recovery, which causes the actual storage capacity and the working gas volume is always less than the designed value. Restricted by the reservoir pore throat heterogeneity and gas drive pressure gradient, and influenced by side water cycle, the capacity expansion increased by the displacement is limited. After injectionproduction simulation, the capacity utilization rate is only 30%, and the working gas volume ratio is also only 21.6%. [ABSTRACT FROM AUTHOR]