Water consumptions in public schools

Water consumption per user in non-residential buildings is still a very complicated issue for engineers and designers in the process of analyzing water demand and water management. It is easier to design for residential units than for public buildings, as you never know exactly how many users will access the building daily, you can just estimate the number. Our goal is not to set certain and fixed numbers, as they probably will never exist, but to analyze the data we gathered through time and to try to get to an approximation of water usage in public schools connected to building occupants. This research integrates quantitative data of water consumption through water metering and historical data about users in buildings. Six hundred buildings have been monitored over a period of 5 years (2005 e 2010).We focused on consumptions for 3 types of schools: Nurseries (0-3 years old children), Kindergartens (3-6 years) and Elementary Schools (6-11 years). Finally we studied how they are linked to building occupants on a daily consumption rate. The results are that the rational basic demand for water is estimated as 48 liters per pre-school student per day and 18 liters per elementary school student per day. Moreover younger children use more water on a daily basis than elementary school students, as they need more services, such as laundries and kitchens, whereas older students consume water mainly in restrooms

Experimental Infiltration Tests on Existing Permeable Pavement Surfaces

This study describes a field investigation that compares water infiltration rates of eight permeable parking lots located in Rimini City, Italy. In the experiment a single ring infiltrometer test was used to analyze the influence of the surface type, filling material, location in the parking stall, pavement age, and antecedent dry weather days on the infiltration capacity of the pavements. The results show that the permeability values are mostly affected by the position of the ring in the parking lot, filling material, and surface type rather than by the antecedent dry weather time and pavement age. The surface infiltration rate of the eight pavements ranges between a minimum of 123mm/h (site 6, permeable interlocking concrete paver, 2005) and a maximum of 20 137mm/h (site 4, concrete grid paver, 2005), exceeding the 97.2mm/h minimum design infiltration rate required by selected European authorities. The results also show that compaction decreases the infiltration rate. Therefore, the study could be useful in setting the standard test procedure to evaluate the performance of permeable pavements over time in the Mediterranean climate

A long-term hydrological modelling of an extensive green roof by means of SWMM

Green roofs provide multiple environmental and social benefits, among which the opportunity to control storm water runoff as they limit the rate of runoff after urbanization to the rate that would have occurred before urban development. The hydrological behaviour of a green roof is site specific, thus the local environmental parameters, the characteristics of the vegetation and the physical properties of its layers have to be considered in the evaluation of its performance. Furthermore, the hydrological performance of a green roof is influenced by the size of the plot (full-scale vs small scale), by the definition of “event”, and by the number of events included in the research. From this broader context this paper first provides a review of the scientific literature, with a focus on the hydrological behaviour of experimental full-scale installations and on hydrological modelling of green roof performance. Second, the study presents the results of a monitoring activity of a full-scale extensive green roof in Bologna (Italy). Continuous weather data and runoff were collected between January and December 2014, resulting in 69 storm events suitable for the study. Experimental data show that single event rainfall attenuation ranged from 6.4% to 100% with an annual average value of 51.9% which is consistent with other author's findings. Last, the study uses the field data to calibrate and validate a numerical model realized with the commercial software SWMM 5.1. The model was used to simulate the long-term hydrologic response, over one year, of the same full-scale extensive green roof and to compare it to an adjacent impervious roof of the same size. Modelling results confirm the role of green roofs in restoring the natural water regime by reducing the annual runoff volume. The comparison of the results between the experimental green roof monitoring and the SWMM simulation proved that the suggested model has good capabilities in simulating the hydrograph of stormwater runoff from green roofs along the year, as demonstrated by the quite high values of NSE and the low value of RSR in both the calibration and validation phase. Furthermore, the low difference (< 9%) in total retention between the 69 measured and simulated events confirms the suitability of the model for long term simulations. The proposed modelling approach demonstrates that SWMM can be used for assessing the performance of LID systems (Low Impact Development), and consequently for supporting local authorities or designers in the evaluation of the hydrological efficiency of green roofs

VALIDITY LIMITS OF THE EXPRESSION FOR MEASURING SOIL RESISTIVITY BY THE WENNER METHOD ACCORDING TO IEEE STANDARD 81-1983

Za analizu rezultata i obavljanje mjerenja specifičnog otpora tla inženjerima su dane na raspolaganje smjernice i naputci različitih međunarodnih normi. Prilikom korištenja matematičkih izraza iz navedenih normi često nisu jasne okolnosti pod kojima su dobiveni navedeni izrazi. Jedan takav slučaj opisan je u ovom članku, a odnosi se na međunarodnu normu IEEE Std. 81-1983, izraz za prividni specifični otpor tla, a koji se odnosi na teorijski model i predviđanje mjernih rezultata dobivenih Wennerovim mjernim rasporedom elektroda. U IEEE Std. 81-1983 štapne elektrode su modelirane kao kuglaste, što u konačnici rezultira jednostavnim matematičkim izrazom za prividni specifični otpor tla. Zbog navedenog pojednostavljenja inženjeri nemaju uvid u granice valjanosti prema normi dobivenog izraza, odnosno njegovu točnost. Naime, pretpostavlja se da korisnik ima predznanje visokog obrazovanja, usmjeravajuće struke ili da je pohađao odgovarajuće tečajeve. Iz tog razloga u članku je detaljno prikazan izvod izraza za prividni specifični otpor tla u slučaju kada se mjerenje obavlja Wennerovom mjernom tehnikom. Izvodi su iscrpno komentirani kako bi iznesena građa bila razumljivija što širem krugu čitatelja. Dobiveni izraz uvažava stvarnu geometriju mjernih elektroda i utjecaj međusobne blizine elektroda na mjerenje. Na primjeru iz prakse uspoređeni su rezultati dobiveni izvedenim izrazom s predloženim izrazom prema međunarodnoj normi IEEE Std. 81-1983. Rezultati oba pristupa prikazani su grafički, analitički te diskutirani.For the analysis of soil resistivity results and measurement, engineers have guidelines and instructions from various international standards at their disposal. The circumstances under which the mathematical expressions in these standards were obtained are not always clear. One such case is described in this article and refers to the international IEEE Standard 81-1983, an expression for apparent soil resistivity, and refers to a theoretical model and the prediction and interpretation of measurement results obtained by using the Wenner method of electrode arrangement. In IEEE Std. 81-1983, rod electrodes are modeled as spherical, which ultimately results in a simplified mathematical expression for apparent soil resistivity. Due to this simplification, the expression in this standard does not provide engineers with insight into its validity limits, i.e. accuracy. It is assumed that the user is highly educated, specialized or has obtained the necessary training. Therefore, this article presents the derivation of the expression for apparent soil resistivity in detail when measurement is performed using the Wenner method. Exhaustive commentary on the derivations is provided so that the material presented will be understood by the widest possible circle of readers. The expression obtained takes the actual geometry of the measurement electrodes and the influence of the distance between the electrodes upon measurement into account. Using a practical example, the results obtained using the derived expression are compared to results obtained using the expression proposed according to the international IEEE Std. 81-1983. The results of both approaches are presented graphically and analytically, and are discussed

Management of cull dairy cows—Consensus of an expert consultation in Canada

Many cull dairy cows enter the marketing system and travel to widely dispersed and specialized slaughter plants, and they may experience multiple handling events (e.g., loading, unloading, mixing), change of ownership among dealers, and feed and water deprivation during transport and at livestock markets. The objectives of this study were to describe the diverse management of cull dairy cows in Canada and establish consensus on ways to achieve improvements. A 2-day expert consultation meeting was convened, involving farmers, veterinarians, regulators, and experts in animal transport, livestock auction, and slaughter. The 15 participants, recruited from across Canada, discussed regional management practices for cull cattle, related risk factors, animal welfare problems, and recommendations. An audio recording of the meeting was used to extract descriptive data on cull cattle management and identify points of agreement. Eight consensus points were reached: (1) to assemble information on travel times and delays from farm to slaughter; (2) to increase awareness among producers and herd veterinarians of potential travel distances and delays; (3) to promote pro-active culling; (4) to improve the ability of personnel to assess animal condition before loading; (5) to identify local options for slaughter of cull dairy cows; (6) to investigate different management options such as emergency slaughter and mobile slaughter; (7) to ensure that all farms and auctions have, or can access, personnel trained and equipped for euthanasia; and (8) to promote cooperation among enforcement agencies and wider adoption of beneficial regulatory options

Uticaj vrste filtera na kvalitet određivanja rastvorljivosti “shake-flask” metodom

The aim of the present study was to examine the influence of the filter type during phase separation on solubility determination. Polyether sulfone (hydrophobic) and polyvinylidene fluoride (hydrophilic) filters were chosen. The concentration was measured by UV/Vis spectrophotometry. Carvedilol (base) and ibuprofen (acid) are used as a model compounds. LogP values were determined by miniaturized shake-flask method and by optimized potentiometric titration. It is shown that solubility data can be influenced by membrane filter type which is used for filtration, after the equilibrium is established during dissolution. Magnitude of this influence depends of lipophilicity and pKa value of molecule and a solution pH value.Cilj ovog rada je ispitivanje uticaja vrste membrane filtera u procesu odvajanja faza pri određivanju rastvorljivosti „shake-flask“ metodom. Izabrani su polietar-sulfon (hidrofobni) i poliviniliden-fluorid (hidrofilni) filteri. Koncentracija je merena pomoću UV/Vis spektrofotometrije. Kao model supstance korišćeni su karvedilol (baza) i ibuprofen (kiselina). Minijaturizovanom „shake-flask“ metodom i optimizovanom metodom potenciometrijske titracije određene su i logP vrednosti. Pokazano je da rezultat određivanja rastvorljivosti može zavisiti od vrste membrane filtera koji se koristi za odvajanje filtrata nakon uspostavljanja ravnoteže u rastvoru tokom rastvaranja. Jačina uticaja zavisi od lipofilnosti i pKa vrednosti ispitavanog molekula kao i od pH vrednosti rastvora u kom se izvodi određivanje

Uticaj vrste filtera na kvalitet određivanja rastvorljivosti “shake-flask” metodom

The aim of the present study was to examine the influence of the filter type during phase separation on solubility determination. Polyether sulfone (hydrophobic) and polyvinylidene fluoride (hydrophilic) filters were chosen. The concentration was measured by UV/Vis spectrophotometry. Carvedilol (base) and ibuprofen (acid) are used as a model compounds. LogP values were determined by miniaturized shake-flask method and by optimized potentiometric titration. It is shown that solubility data can be influenced by membrane filter type which is used for filtration, after the equilibrium is established during dissolution. Magnitude of this influence depends of lipophilicity and pKa value of molecule and a solution pH value.Cilj ovog rada je ispitivanje uticaja vrste membrane filtera u procesu odvajanja faza pri određivanju rastvorljivosti „shake-flask“ metodom. Izabrani su polietar-sulfon (hidrofobni) i poliviniliden-fluorid (hidrofilni) filteri. Koncentracija je merena pomoću UV/Vis spektrofotometrije. Kao model supstance korišćeni su karvedilol (baza) i ibuprofen (kiselina). Minijaturizovanom „shake-flask“ metodom i optimizovanom metodom potenciometrijske titracije određene su i logP vrednosti. Pokazano je da rezultat određivanja rastvorljivosti može zavisiti od vrste membrane filtera koji se koristi za odvajanje filtrata nakon uspostavljanja ravnoteže u rastvoru tokom rastvaranja. Jačina uticaja zavisi od lipofilnosti i pKa vrednosti ispitavanog molekula kao i od pH vrednosti rastvora u kom se izvodi određivanje

The effect of the filter type on the quality of “shake flask” solubility determinations

Određivanje rastvorljivosti je važno u svim fazama razvoja leka. Dobijeni podaci se koriste za nalaženje potencijalnih lekova-kandidata, biofarmaceutsku klasifikciju i optimizaciju formulacije leka. Na merenje rastvorljivosti utiču različiti faktori: vreme mešanja, vreme sedimentacije, sastav pufera, temperatura, višak čvrste faze i tehnika odvajanja faza.[1] Cilj ovog rada je ispitivanje uticaja vrste membrane filtera u procesu odvajanja faza pri određivanju rastvorljivosti „shake-flask“ metodom. Izabrani su polietar-sulfon (hidrofobni) i poliviniliden-fluorid (hidrofilni) filteri. Koncentracija je merena pomoću UV/Vis spektrofotometrije. Kao model supstance korišćeni su karvedilol (baza) i ibuprofen (kiselina). Minijaturizovanom „shake-flask“ metodom i optimizovanom metodom potenciometrijske titracije određene su i logP vrednosti. Pokazano je da rezultat određivanja rastvorljivosti može zavisiti od vrste membrane filtera koji se koristi za odvajanje filtrata nakon uspostavljanja ravnoteže u rastvoru tokom rastvaranja. Jačina uticaja zavisi od lipofilnosti i pKa vrednosti ispitavanog molekula kao i od pH vrednosti rastvora u kom se izvodi određivanje.Solubility determination is important in both early and development phase of drug research. This data is used to screen out drug-like candidates, biopharmaceutical classification and formulation optimization. Solubility measurements are influenced by several experimental factors: stirring and sedimentation time, composition of the aqueous buffer, temperature, amount of solid excess and the technique of phase-separation.1 The aim of the present study was to examine the influence of the filter type during phase separation on solubility determination. Polyether sulfone (hydrophobic) and polyvinylidene fluoride (hydrophilic) filters were chosen. The concentration was measured by UV/Vis spectrophotometry. Carvedilol (base) and ibuprofen (acid) are used as a model compounds. LogP values were determined by miniaturized shake-flask method and by optimized potentiometric titration. It is shown that solubility data can be influenced by membrane filter type which is used for filtration, after the equilibrium is established during dissolution. Magnitude of this influence depends of lipophilicity and pKa value of molecule and a solution pH valu

Developmental perspectives on Europe

The crisis of 2008–2009 has ended, stockmarkets skyrocketed in 2012–2013, while growth of the real sector remained sluggish in Europe. This article attempts to explain the latter puzzle. Analyzing long term factors, the costs of short-termism in crisis management become obvious. The limitations of EU as a growth engine are highlighted