scholarly journals Modelling of a roof runoff harvesting system: the use of rainwater for toilet flushing

2011 ◽  
Vol 11 (2) ◽  
pp. 151-158 ◽  
Author(s):  
C. Vialle ◽  
C. Sablayrolles ◽  
M. Lovera ◽  
M.-C. Huau ◽  
M. Montréjaud-Vignoles
Keyword(s):  
Storage Capacity ◽  
Rainwater Harvesting ◽  
Dead Volume ◽  
Optimal Size ◽  
Single Family ◽  
Toilet Flushing ◽  
The Difference ◽  
Predicted Values ◽  
Experimental Values

The water balance of a four-people family rainwater harvesting system was calculated in a case study. The experimental water saving efficiency (WSE) was calculated as 87%. A simple computer model was implemented to simulate the behaviour of the rainwater harvesting system. In general, the rainwater collector volumes predicted by the daily model had shown a good correlation with the experimental values. The difference between the experimental and the predicted values for the stored volume can be explained by the lack of maintenance of the system that can affect its performance. On the basis of a long-term simulation of 20-year rainfall data, the following parameters were calculated: rainfall, water demand, mains water, rainwater used, over-flow and WSE. The collection of rainwater from roofs, its storage and subsequent use for toilet flushing can save 42 m3 of potable water per year for the studied system. The model was also used to find the optimal size of the tank for the single-family household: a storage capacity of approximately 5 m3 was found to be appropriate. The storage capacity and tank size were distinguished. The importance to take into account the dead volume of the tank for the sizing was indeed highlighted.

Thermoelectric Power of the Liquid Sn—Te Alloy

1982 ◽  
Vol 37 (10) ◽  
pp. 1127-1131 ◽  
Author(s):  
D. H. Kurlat ◽  
M. Rosen
Keyword(s):  
Thermoelectric Power ◽  
Hard Sphere ◽  
Stoichiometric Composition ◽  
Band Model ◽  
Liquid Alloys ◽  
Sphere Approximation ◽  
The Difference ◽  
Predicted Values ◽  
Experimental Values ◽  
Two Band Model

The Seebeck coefficient (S) of Sni1-x- Tex liquid alloys was measured as a function of concentration and temperature. For 0 ≦ x <0.45 the behaviour is metallic; S values are small and negative, rising linearly with temperature. The predicted values of Ziman's theory when using the hard sphere approximation disagree with the experimental ones. The change in sign occurs for 0.45. For x = 0.5 (stoichiometric composition) the thermoelectric power decreases linearly with temperature. This fact is explained assuming a two-band model. For x ≧ 0.6 the liquid alloy becomes more semiconducting and presents a maximum in the isotherms of S for x = 0.65. For the excess tellurium concentration range we have calculated the difference EF - EV and γ/kB, assuming a S(1/T) law. The experimental values are compared with those of Dancy and Glazov.

scholarly journals Optimum Matching Model Using Long-Term Computing on Safer Rural Domestic Water Supply Based on Rainwater Harvesting

2018 ◽  
Vol 15 (12) ◽  
pp. 2864 ◽  
Author(s):  
Yan-Zhao Jin ◽  
Lu-Wen Zhou ◽  
Kwong Lo
Keyword(s):  
Water Supply ◽  
Rural Areas ◽  
Storage Capacity ◽  
Rainwater Harvesting ◽  
Supply And Demand ◽  
Computation Method ◽  
Matching Model ◽  
Domestic Water ◽  
Domestic Water Supply

A safe rural domestic water supply project has been initiated based on different consumption uses. Long-term computation method and the water balance principle are used to analyze the yearly water demand. Water supply and demand balance is achieved through regulated planning of the rainwater collection surface area and water storage capacity. The best combination of collection area and storage capacity is then determined for various rainfall zones in order to satisfy safe domestic water needs. Ultimately, an optimum matching model is developed to utilize rainwater harvesting for providing safe domestic water in rural areas.

Plugrisost: a model for design, economic cost and environmental analysis of rainwater harvesting in urban systems

2014 ◽  
Vol 9 (2) ◽  
pp. 243-255 ◽  
Author(s):  
X. Gabarrell ◽  
T. Morales-Pinzón ◽  
J. Rieradevall ◽  
M. R. Rovira ◽  
G. Villalba ◽  
...  
Keyword(s):  
Environmental Analysis ◽  
Rainwater Harvesting ◽  
Smart Cities ◽  
Tap Water ◽  
Environmental Indicators ◽  
Urban Systems ◽  
Optimal Size ◽  
Single Family ◽  
Successful Operation ◽  
Rainwater Tank

In the context of transition to sustainability, one of the main challenges facing societies today is the supply of water. By integrating different methodological tools and studies we developed the innovative software program Plugrisost® (rainwater, greys and sustainability), a simulation model, that facilitates the economic evaluation and the potential environmental impact of alternative water supplies (rainwater harvesting [RWH] and greywater systems) at different scales of urban planning. This modelling tool contributes to urban water planning for smart cities development. Plugrisost® analyses the optimal design variables, cost and environmental performance of RWH and greywater systems, using tap water production as a reference system for comparison. The use of economic and environmental indicators can make the optimal size of a rainwater tank more restrictive when it is compared to the results regarding the satisfaction of the demand for rainwater. Economic and environmental analysis can help avoid oversizing tanks for rainwater and thus obtain greater benefits. Plugrisost includes estimated cost and Global Warming Potential, as well as other life cycle impact indicators for this purpose. A case study analyzing the implementation of a RWH system in a single-family house in Aveiro, Portugal is included, showing the importance of rainwater availability and demand for the successful operation of simulated systems.

scholarly journals Estimating the First-year Corrosion Losses of Structural Metals for Continental Regions of the World

2020 ◽  
Vol 6 (8) ◽  
pp. 1503-1519 ◽  
Author(s):  
Yu. M. Panchenko ◽  
A. I. Marshakov ◽  
L. A. Nikolaeva ◽  
T. N. Igonin
Keyword(s):  
Dose Response ◽  
First Year ◽  
Response Functions ◽  
The World ◽  
Structural Metals ◽  
Predicted Values ◽  
Experimental Values ◽  
First Time ◽  
Statistical Indicators

The knowledge of the first-year corrosion losses of metals (K1) in various regions of the world is of great importance in engineering applications. The K1 values are used to determine the categories of atmospheric corrosivity, and K1 is also the main parameter in models for the prediction of long-term corrosion losses of metals. In the absence of experimental values of K1, their values can be predicted on the basis of meteorological and aerochemical parameters of the atmosphere using the dose-response functions (DRF). Currently, the DRFs presented in ISO 9223:2012(E) /1/ standard are used for predicting K1 in any region of the world, along with the unified DRFs /2/ and the new DRFs /3/. The predicted values of corrosion losses (K1pr) of carbon steel, zinc, copper and aluminum obtained by various DRFs for various continental regions of the world are presented. In this work we used the atmosphere corrosivity parameters and experimental data on the corrosion losses of metals for the first year of exposure (K1exp) for the locations of the tests performed under the international UN/ECE program, the MICAT project, and the Russian program. For the first time, a comparative assessment of the reliability of various DRFs is given by comparing the values of K1pr and K1ex using graphical and statistical methods. The statistical indicators of reliability of predicting the corrosion losses of metals are calculated for various categories of atmosphere corrosivity. It is shown that the new dose-response functions offer the highest reliability for all categories of atmosphere corrosivity.

scholarly journals Evaluation of the optimal size of a rainwater harvesting system in Sicily

2017 ◽  
Vol 19 (6) ◽  
pp. 853-864 ◽  
Author(s):  
Vincenza Notaro ◽  
Lorena Liuzzo ◽  
Gabriele Freni
Keyword(s):  
Water Scarcity ◽  
Rainwater Harvesting ◽  
Temporal Distribution ◽  
Mediterranean Area ◽  
Critical Issue ◽  
Economic Benefits ◽  
Optimal Size ◽  
Single Family ◽  
Optimal Capacity ◽  
Alternative Water

Abstract In the Mediterranean area, water scarcity represents a critical issue due to the increasing water demand related to the population growth and the expansion of urban and industrialized areas. Rainwater harvesting (RWH) may be an effective alternative water supply solution to deal with water scarcity in order to reduce non-potable water needs. The reliability of RWH systems is greatly affected by the intensity and the temporal distribution of rainfall events. The purpose of the present study was to identify the optimal tank capacity, in terms of water saving efficiency, of a RWH system installed to supply water for toilet flushing, garden irrigation and both uses with reference to a single-family house in a residential area of Sicily (southern Italy). A water balance simulation of the rainwater storage tank was performed to define the tank release rule. The optimal capacity of the RWH tank was evaluated considering three different catchment surfaces, namely 100, 200 and 300 m2. Results showed that, in some areas of the region, the system could be able to provide significant water savings, even with the installation of collecting tanks of less than 10 m3, thus ensuring important environmental and economic benefits to the householders.

A Problem of Long - Term Digital Preservation: Difference in Humanities and Natural Sciences

2014 ◽  
Vol 3 ◽  
pp. 183-195
Author(s):  
Elena Macevičiūtė
Keyword(s):  
Social Sciences ◽  
Digital Preservation ◽  
Dynamic Activity ◽  
Private Companies ◽  
Time Line ◽  
Digital Documents ◽  
Whole Process ◽  
The Difference ◽  
Technological Science

The article deals with the requirements and needs for long-term digital preservation in different areas of scholarly work. The concept of long-term digital preservation is introduced by comparing it to digitization and archiving concepts and defined with the emphasis on dynamic activity within a certain time line. The structure of digital preservation is presented with regard to the elements of the activity as understood in Activity Theory. The life-cycle of digitization processes forms the basis of the main processing of preserved data in preservation archival system.The author draws on the differences between humanities and social sciences on one hand and natural and technological science on the other. The empirical data characterizing the needs for digital preservation within different areas of scholarship are presented and show the difference in approaches to long-term digital preservation, as well as differences in selecting the items and implementing the projects of digital preservation. Institutions and organizations can also develop different understanding of preservation requirements for digital documents and other objects.The final part of the paper is devoted to some general problems pertaining to the longterm digital preservation with the emphasis of the responsibility for the whole process of safe-guarding the cultural and scholarly heritage for the re-use of the posterior generations. It is suggested that the longevity of the libraries in comparison with much shorter life-span of private companies strengthens the claim of memory institutions to playing the central role in the long-term digital preservation.

Effect of sleep on memory for binding different types of visual information

2020 ◽  
Author(s):  
John J Shaw ◽  
Zhisen Urgolites ◽  
Padraic Monaghan
Keyword(s):  
Visual Information ◽  
Storage Capacity ◽  
Declarative Memory ◽  
Recognition Task ◽  
Forced Choice ◽  
Long Term Memory ◽  
Term Memory ◽  
Different Types ◽  
Types Of Information

Visual long-term memory has a large and detailed storage capacity for individual scenes, objects, and actions. However, memory for combinations of actions and scenes is poorer, suggesting difficulty in binding this information together. Sleep can enhance declarative memory of information, but whether sleep can also boost memory for binding information and whether the effect is general across different types of information is not yet known. Experiments 1 to 3 tested effects of sleep on binding actions and scenes, and Experiments 4 and 5 tested binding of objects and scenes. Participants viewed composites and were tested 12-hours later after a delay consisting of sleep (9pm-9am) or wake (9am-9pm), on an alternative forced choice recognition task. For action-scene composites, memory was relatively poor with no significant effect of sleep. For object-scene composites sleep did improve memory. Sleep can promote binding in memory, depending on the type of information to be combined.

CSO Modelling Considering Moving Storms and Tipping Bucket Gauge Failures

2007 ◽  
Vol 2 (1) ◽  
Author(s):  
M. Hochedlinger ◽  
W. Sprung ◽  
H. Kainz ◽  
K. König
Keyword(s):  
Hydrological Models ◽  
Rain Intensity ◽  
Hydrodynamic Models ◽  
Data Intensive ◽  
Storm Flow ◽  
Cell Velocity ◽  
Combined Sewer ◽  
Moving Direction ◽  
The Difference

The simulation of combined sewer overflow volumes and loads is important for the assessment of the overflow and overflow load to the receiving water to predict the hydraulic or the pollution impact. Hydrodynamic models are very data-intensive and time-consuming for long-term quality modelling. Hence, for long-term modelling, hydrological models are used to predict the storm flow in a fast way. However, in most cases, a constant rain intensity is used as load for the simulation, but in practice even for small catchments rain occurs in rain cells, which are not constant over the whole catchment area. This paper presents the results of quality modelling considering moving storms depending on the rain cell velocity and its moving direction. Additionally, tipping bucket gauge failures and different corrections are also taken into account. The results evidence the importance of these considerations for precipitation due the effects on overflow load and show the difference up to 28% of corrected and uncorrected data and of moving rain cells instead of constant raining intensities.

Application of Pregelatinized Meal of Rice and Sorghum in the Preparation of Instant Soups: Centesimal Characterization, Technological, Microbiological and Sensory Quality

2019 ◽  
Vol 15 ◽  
Author(s):  
Gomes Acg ◽  
Lima Mcpm ◽  
Caliari M ◽  
Alves Dg ◽  
Machado Alb ◽  
...  
Keyword(s):  
Fast Food ◽  
Water Solubility ◽  
Potato Starch ◽  
Rice Flour ◽  
Extrusion Process ◽  
Experimental Development ◽  
Sorghum Flour ◽  
Predicted Values ◽  
Experimental Values ◽  
Physical And Chemical

Due to the technological importance that the extrusion process represents in the application of fast food, the objective of this work was to apply pregelatinized rice and sorghum flours in the development of an instant preparation soup and to evaluate its centesimal, technological, and their sensorial analysis. Ten formulations of the instant soup were prepared from the mixtures experimental design. According to the experimental results, it can be stated that the predicted values corroborated with the experimental values, that is, a mixture was obtained for the instant soup with the characteristics of water absorption, water solubility, color, luminosity and viscosity close to the predicted by the models. After the physical and chemical analysis, the microbiological characterization of the best formulation defined by the desirability test was used, which demonstrated that the product is suitable to microbiological standards. The results obtained showed that the 80:10:10 instant soup formulation of pregelatinized rice flour, pregelatinized sorghum flour and potato starch allowed the experimental development of a new product with good nutritional characteristics benefits. It was obtained a food with good technological characteristics solubility and absorption in water, good viscosity, light color and with good sensory acceptance by the tasters.

The metachor as a characteristic of the association of electrolytes in aqueous solutions

1984 ◽  
Vol 49 (5) ◽  
pp. 1061-1078 ◽  
Author(s):  
Jiří Čeleda ◽  
Stanislav Škramovský
Keyword(s):  
Aqueous Solutions ◽  
Apparent Volume ◽  
Solutions Of Electrolytes ◽  
Molal Volumes ◽  
The Difference ◽  
High Concentrations ◽  
Experimental Values ◽  
Suitable Characteristic ◽  
Association Of Ions ◽  
Very High

Based on the earlier paper introducing a concept of the apparent parachor of a solute in the solution, we have eliminated in the present work algebraically the effect which is introduced into this quantity by the additivity of the apparent molal volumes. The difference remaining from the apparent parachor after substracting the contribution corresponding to the apparent volume ( for which the present authors suggest the name metachor) was evaluated from the experimental values of the surface tension of aqueous solutions for a set of 1,1-, 1,2- and 2,1-valent electrolytes. This difference showed to be independent of concentration up to the very high values of the order of units mol dm-3 but it was directly proportional to the number of the free charges (with a proportionality factor 5 ± 1 cm3 mol-1 identical for all studied electrolytes). The metachor can be, for this reason, a suitable characteristic for detection of the association of ions and formation of complexes in the solutions of electrolytes, up to high concentrations where other methods are failing.

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