Average Temperature Model of Double-Row-Pipe Frozen Soil Wall by Equivalent Trapezoid Method

2010 ◽  
Author(s):  
Xiang-dong Hu ◽  
Jane W. Z. Lu ◽  
Andrew Y. T. Leung ◽  
Vai Pan Iu ◽  
Kai Meng Mok
Keyword(s):  
Frozen Soil ◽  
Temperature Model ◽  
Double Row ◽  
Average Temperature ◽  
Trapezoid Method

Optimization of Double-Ring-Pipe Freezing Scheme for Tunnel Cross-Passage Construction

2012 ◽  
Vol 446-449 ◽  
pp. 2262-2266 ◽  
Author(s):  
Xiang Dong Hu ◽  
Bing Yi Ji
Keyword(s):  
Frozen Soil ◽  
Shield Tunnel ◽  
Freezing Process ◽  
Unfrozen Water ◽  
Double Ring ◽  
Average Temperature ◽  
Unfrozen Water Content ◽  
Ground Freezing ◽  
Different Temperatures ◽  
Frozen Wall

For numerically simulating the phase change of water in ground freezing process, a correct method is proposed in this paper, that the unfrozen water content in frozen soil is taken into account to calculate the enthalpy value at different temperatures. A calculation example of a cross-passage project in shield tunnel shows that the thickness and the average temperature of the frozen wall calculated by this method are very close to the in-situ monitored data. Based on this method, by comparison of the development rate of thickness and the average temperature of the frozen wall according to different design plans, the ground freezing scheme for the cross-passage is optimized for the shortest duration of freeze in agreement with the work standard. The study could enlighten the design for similar projects in the future.

scholarly journals Quality of silage produced from intercropped corn RR and soybeans RR

2019 ◽  
Vol 35 (6) ◽  
Author(s):  
Isabella Sichierski Cardoso ◽  
Adriano Jakelaitis ◽  
Karolyna Oliveira Marques ◽  
Katia Cylene Guimarães ◽  
Leandro Spíndola Pereira
Keyword(s):  
Block Design ◽  
Grain Filling ◽  
Experimental Period ◽  
Neutral Detergent Fiber ◽  
Double Row ◽  
Average Temperature ◽  
Randomized Block Design ◽  
Secondary Factor ◽  
Fertilization System

The objective of this study was to produce silage from intercropped RR glyphosate tolerant corn (RR - Roundup Ready) and RR soybeans under Brazilian Cerrado conditions. The research was carried out in off-season between February and June 2015, in Rio Verde, Goiás (Brazil). In the experimental period the rainfall was 865 mm and the average temperature of 23.7°C. Two trials were performed. The first had corn rows spaced in 1 m with a row of soybeans in the interrow. The second had double corn rows interspersed with one row of soybeans, all spaced in 0.50 m. In both trials, we used a randomized block design, in a 2x2+3 factorial scheme, with four replications. Primary factor consisted of two types of pre-sowing fertilization: one only in corn rows and the other over the total area. The secondary factor corresponded to two soybean varieties: medium and late cycle variety. In addition, three control treatments were made: one of corn and two of soybeans. The corn cutoff point was at the hard farinaceous stage when the milk line reaches half the grain, and in the sole crop soybean at the R5.5 final phase of grain filling. Silage was stored in PVC experimental silos for 60 days. The intercropped treatments, in both spatial arrangements, promoted increases in neutral detergent fiber and acid detergent fiber contents. Soybean monoculture presented high values of crude protein and ethereal extract. There were higher effluent losses in medium-cycle soybean variety silage when it was grown in single cropping. However, the lowest effluent losses were recorded for silages of medium-cycle soybean intercropped under a double row pre-sowing corn fertilization system. The soybeans mixed silages produced together with corn under off-season conditions did not yield satisfactory results.

scholarly journals Yield of cocoa under different agroforestry systems in a dry tropical forest in western Colombia

2021 ◽  
Vol 34 (1) ◽  
pp. 39-50
Author(s):  
Carlos H. Escobar Ramírez ◽  
Óscar de J. Córdoba-Gaona ◽  
Guillermo A. Correa Londoño ◽  
Enrique G. Martínez Bustamante
Keyword(s):  
Tropical Dry Forest ◽  
Genetic Material ◽  
Agroforestry Systems ◽  
Dry Forest ◽  
Timber Species ◽  
Double Row ◽  
Average Temperature ◽  
Productive Potential ◽  
Life Zone ◽  
New Strategies

The expansion and modernization of the cocoa area under new strategies, such as the use of adapted genetic material and the establishment of Agroforestry Systems with cocoa, under criteria of competitiveness and sustainability, require selecting sites with adequate biophysical conditions, which facilitate the optimization of resources for production. In this sense, we conducted a study in the Estación Agraria Cotové, of the Universidad Nacional de Colombia, located in a tropical dry forest life zone (TDF), at 540 meters of elevation, with an average temperature of 27 ºC, average annual precipitation annual of 1,031 mm and relative humidity less than 70 %. The yield components and productive potential of four cocoa clones, ICS 95, TSH565, CCN 51, and ICS 60, were evaluated. The cocoa clones were planted under two controlled sunlight habitats, generated by the timber species Gmelina arborea Roxb. (single-row and double-row arrangement), and two different canopy management of the cocoa plants (plagiotropic and orthotropic growth stimulus). The clones TSH 565 and CCN 51 showed the highest yields in the two harvest years. ICS 95 showed the lowest bean index. Regarding the pod index, no differences were observed between the cocoa clones. Clones TSH 565 and CCN 51 stood out as the earliest and most productive clones.

PRICING TEMPERATURE DERIVATIVES UNDER WEATHER FORECASTS

2018 ◽  
Vol 21 (05) ◽  
pp. 1850031 ◽  
Author(s):  
MARKUS HESS
Keyword(s):  
Option Pricing ◽  
Portfolio Selection ◽  
Minimum Principle ◽  
Temperature Model ◽  
Weather Derivatives ◽  
Weather Forecasts ◽  
Additional Information ◽  
Average Temperature ◽  
Degree Day ◽  
Minimal Variance

We investigate the pricing of temperature derivatives under weather forecasts modeled by initially enlarged filtrations. For this purpose, we introduce a mean-reverting temperature model with seasonality and derive expressions for the so-called forward temperature. Although our analysis focuses on cumulative average temperature (CAT) futures, the presented derivation techniques can likewise be applied to other weather derivatives such as heating degree day (HDD) or cooling degree day (CDD) futures, for instance. We also treat option pricing and utility maximizing portfolio selection in temperature markets under additional information on future weather behavior. We finally prove an anticipative sufficient stochastic minimum principle in an enlarged filtration setup and apply the result to minimal variance hedging of temperature derivatives under weather forecasts. In this context, we derive explicit minimal variance hedging portfolios for different weather-related claims.

A Study on SCWR Core Design and Fuel Management

2013 ◽  
Author(s):  
Yong Zhang ◽  
Jue Yang ◽  
Dongsheng Li ◽  
Liangzhi Cao ◽  
Fei Wang ◽  
...  
Keyword(s):  
Thermal Power ◽  
Coolant Temperature ◽  
Equivalent Diameter ◽  
Fuel Management ◽  
Double Row ◽  
Fuel Rods ◽  
Average Temperature ◽  
The Core ◽  
Fuel Assemblies ◽  
Operation Pressure

A type of SCWR core design with Double-row fuel rods assembly will be introduced in this paper. The Double-row fuel rods SCWR (DL-SCWR) core is designed for reaching a thermal power of 2280 MW with an equivalent diameter of 3.16 m and length of 4.20 m. There are 249 fuel assemblies in the core, and 180 fuel rods in each assembly. The inlet coolant temperature is 280 °C and the operation pressure is 25 MPa. There are 80 fresh assemblies in the equilibrium cycle. The numerical results show that the average discharged burnup of the equilibrium is 37 GWD/tU, and the average temperature of outlet coolant is 500°C. In the equilibrium cycle, the maximum cladding surface temperature is less than 650 °C.

The Effect of Dissipation on the Moulding of Composite Articles in Closed Moulds

2018 ◽  
Vol 45 (6) ◽  
pp. 265-268
Author(s):  
A. V. Baranov ◽  
S.A. Yunitskii
Keyword(s):  
Heat Exchange ◽  
Energy Equation ◽  
Point Of View ◽  
Brinkman Equation ◽  
Temperature Model ◽  
Brinkman Number ◽  
Power Law Fluid ◽  
Average Temperature ◽  
Dissipative Heat ◽  
Single Temperature

The flow and heat exchange in the process of impregnation of filler by non-Newtonian fluid during the moulding of composite articles in closed moulds are investigated. Flow is described by the modified Brinkman equation. From the rheological point of view, the medium comprises a power-law fluid. In writing the energy equation, a single-temperature model is used. Dissipative heat generation is taken into account. The problem is solved by the numerical finite difference method. The effect of dissipation (the Brinkman number) on the distribution of the mass-average temperature over the length of the cavity with different Péclet numbers is shown.

Weather derivatives for managing weather and climate risk in agriculture

2020 ◽  
Vol 07 (04) ◽  
pp. 2050049
Author(s):  
Samuel Asante Gyamerah ◽  
Philip Ngare ◽  
Dennis Ikpe
Keyword(s):  
Regime Switching ◽  
Agricultural Sector ◽  
Temperature Model ◽  
Pricing Model ◽  
Weather Derivatives ◽  
Average Temperature ◽  
Single Location ◽  
The Future ◽  
The Individual ◽  
Switching Temperature

In this paper, we develop a pricing model for weather derivatives at a single location and multiple locations. In the first model, a Lévy regime-switching temperature model for a single location is used to price futures written on cumulative average temperature and growing degree-days indices at a single location. To allow analytical pricing for futures on temperature basket, an [Formula: see text]-dimension regime-switching temperature model whose driving noise is captured by a Brownian motion is developed. The correlation between the driving noise in each regime is assumed to be a function of the space between the different farming locations and increases with decreasing space. The temperature basket index assigns a weight to each location that is exposed to risk. However, a location with a higher risk is assigned a larger weight and vice versa. By assuming that the regimes are independent to each other, the future is calculated for each regime model. The final futures price is calculated using the weighted sum of the individual regimes. These pricing models can be applied in the future markets to price weather derivatives for the agricultural sector. Research on spatial-temporal pricing model is vital to the development of the weather derivatives market, as investors are more vulnerable to temperature risk over different farming locations as compared to single location.

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