Application of logistic regression to simulate the influence of rainfall genesis on storm overflow operations: a probabilistic approach

Abstract. One of the key parameters constituting the basis for the operational assessment of stormwater systems is the annual number of storm overflows. Since uncontrolled overflows are a source of pollution washed away from the surface of the catchment area, which leads to imbalanced receiving waters, there is a need for their prognosis and potential reduction. The paper presents a probabilistic model for simulating the annual number of storm overflows. In this model, an innovative solution is to use the logistic regression method to analyze the impact of rainfall genesis on the functioning of a storm overflow (OV) in the example of a catchment located in the city of Kielce (central Poland). The developed model consists of two independent elements. The first element of the model is a synthetic precipitation generator, in which the simulation of rainfall takes into account its genesis resulting from various processes and phenomena occurring in the troposphere. This approach makes it possible to account for the stochastic nature of rainfall in relation to the annual number of events. The second element is the model of logistic regression, which can be used to model the storm overflow resulting from the occurrence of a single rainfall event. The paper confirmed that storm overflow can be modeled based on data on the total rainfall and its duration. An alternative approach was also proposed, providing the possibility of predicting storm overflow only based on the average rainfall intensity. Substantial simplification in the simulation of the phenomenon under study was achieved compared with the works published in this area to date. It is worth noting that the coefficients determined in the logit models have a physical interpretation, and the universal character of these models facilitates their easy adaptation to other examined catchment areas. The calculations made in the paper using the example of the examined catchment allowed for an assessment of the influence of rainfall characteristics (depth, intensity, and duration) of different genesis on the probability of storm overflow. Based on the obtained results, the range of the variability of the average rainfall intensity, which determines the storm overflow, and the annual number of overflows resulting from the occurrence of rain of different genesis were defined. The results are suited for the implementation in the assessment of storm overflows only based on the genetic type of rainfall. The results may be used to develop warning systems in which information about the predicted rainfall genesis is an element of the assessment of the rainwater system and its facilities. This approach is an original solution that has not yet been considered by other researchers. On the other hand, it represents an important simplification and an opportunity to reduce the amount of data to be measured

Field test and probabilistic analysis of irregular steel debris casualty risks from a person-borne improvised explosive device

Person-borne improvised explosive devices (PBIEDs) are often used in terrorist attacks in Western countries. This study aims to predict the trajectories of PBIED fragments and the subsequent safety risks for people exposed to this hazard. An explosive field test with a typical PBIED composed of a plastic explosive charge and steel nut enhancements was performed to record initial fragment behaviour, including positions, velocity, and trajectory angles. These data were used to predict the full trajectory of PBIED fragments using a probabilistic analysis. In the probabilistic analyses a probability of fatality or serious injury was computed. Based on the results presented, many practical conclusions can be drawn, for instance, regarding safe evacuation distances if a person were exposed to a suspected PBIED

Distillation of entanglement by projection on permutationally invariant subspaces

We consider distillation of entanglement from two qubit states which are mixtures of three mutually orthogonal states: two pure entangled states and one pure product state. We distill entanglement from such states by projecting n copies of the state on permutationally invariant subspace and then applying one-way hashing protocol. We find analytical expressions for the rate of the protocol. We also generalize this method to higher dimensional systems. To get analytical expression for two qubit case, we faced a mathematical problem of diagonalizing a family of matrices enjoying some symmetries w.r.t. to symmetric group. We have solved this problem in two ways: (i) directly, by use of Schur-Weyl decomposition and Young symmetrizers (ii) showing that the problem is equivalent to a problem of diagonalizing adjacency matrices in a particular instance of a so called algebraic association scheme.Comment: 22 pages, comments welcom

Sensitivity analysis of sandwich beams and plates accounting for variable support conditions

The paper addresses the problems of the sensitivity analysis and optimal design of multi-span sandwich panels with a soft core and flat thin steel facings. The response functional is formulated in a general form allowing wide practical applications. Sensitivity gradients of this functional with respect to dimensional, material and support parameters are derived using adjoint variable method. These operators account for the jump of the slope of a Timoshenko beam or a Reissner plate at the position of concentrated active load or reaction, thus extending the sensitivity operators known in literature. The jump of slope is the effect of shear deformation of the core. Special attention is focussed on sensitivity and optimisation allowing for variable support position and stiffness, because local phenomena observed in supporting area of sandwich plates often initiate failure mechanisms. Introducing optimally located elastic supports allows to reduce the unfavourable influence of temperature on the state of stress. Several examples illustrate the application of derived sensitivity operators and demonstrate their exactness

Optymalne projektowanie płyt warstwowych z miękkim rdzeniem

The main issue taken up in the paper is to find optimal designs of multispan sandwich panels with slightly profiled steel facings and polyurethane foam core (PUR), which would satisfy conflicting demands of the market, i.e. minimal variance in types of panels, maximum range of application and minimum cost. The aim is to find dimensional and material parameters of panels which generate minimum cost and maximum length of span under prescribed loads in ultimate and serviceability limit states. The multi-criterion optimization problem is formulated in such a way, where the length of the span plays two roles, namely a design variable and a component of a vector objective function. An evolutionary algorithm is used. Numerous inequality constraints are introduced in two ways: directly and by external penalty functions.Wpracy podejmuje się problem optymalizacji wieloprzęsłowych płyt warstwowych z rdzeniem z poliuretanu (PUR) i okładzinami stalowymi lekko profilowanymi. Poszukuje się rozwiązań, które spełnią sprzeczne wymagania rynku, mianowicie: minimalizację typoszeregu płyt, maksymalizację zakresu ich zastosowania oraz minimalizację kosztu produkcji. Celem optymalizacji jest znalezienie parametrów geometrycznych i materiałowych płyt warstwowych, które minimalizują koszt oraz maksymalizują dopuszczalną rozpiętość dla ustalonych obciążeń i przy spełnieniu stanów granicznych nośności i użytkowalności. W wielokryterialnym sformułowaniu problemu optymalizacyjnego rozpiętość pełni dwie funkcje. Jest ona równocześnie zmienną projektową i składową wektora funkcji celu. Jako narzędzie optymalizacji wykorzystano algorytmy genetyczne. Ograniczenia nierównościowe wprowadzono do procedury optymalizacyjnej za pomocą zewnętrznej funkcji kary oraz jawnie

Effects of combined maternal administration with alpha-ketoglutarate (AKG) and <it>β</it>-hydroxy-<it>β</it>-methylbutyrate (HMB) on prenatal programming of skeletal properties in the offspring

Abstract Background Nutritional manipulations during fetal growth may induce long-term metabolic effects in postnatal life. The aim of the study was to test whether combined treatment of pregnant sows with alpha-ketoglutarate and β-hydroxy-β-methylbutyrate induces additive long-term effects on skeletal system properties in the offspring. Methods The study was performed on 290 pigs obtained from 24 sows divided into 4 equal groups and subjected to experimental treatment during two weeks before delivery. The first group consisted of control sows, while the second group received alpha-ketoglutarate. The third group was treated with β-hydroxy-β-methylbutyrate and the fourth group underwent combined administration of alpha-ketoglutarate and β-hydroxy-β-methylbutyrate. Piglets obtained from sows were reared until slaughter age to perform morphometric, densitometric and mechanical analyses of femur. Serum evaluations of growth hormone, insulin-like growth factor-1, bone-specific alkaline phosphatase and osteocalcin were performed in newborns and 90-day old piglets; additionally, plasma amino acid concentration was measured in newborns. Results Maternal treatment with alpha-ketoglutarate and β-hydroxy-β-methylbutyrate significantly reduced fattening time and increased birth body weight, daily body weight gain, bone weight, volumetric bone mineral density, geometrical parameters and mechanical endurance of femur. These effects were associated with increased serum concentrations of growth hormone, insulin-like growth factor-1, bone-specific alkaline phosphatase and osteocalcin. Furthermore, alpha-ketoglutarate and β-hydroxy-β-methylbutyrate administered solely or in combination significantly increased plasma level of 19 amino acids. Conclusions Hormonal and amino acid evaluations in pigs indicate additive effects of AKG and HMB on systemic growth and development; however, determination of bone properties has not shown such phenomenon.</p

Structure, thermal characterization and mechanical properties of poly(phenylene oxide) and high impact polystyrene blend

Zbadano strukturę oraz właściwości termiczne i mechaniczne mieszanin poli(tlenku fenylenu) (PPO) zwysokoudarowym polistyrenem (HIPS). Stosowano dwa rodzaje PPO: handlowy (PPO-h) oraz otrzymany wInstytucie Chemii Przemysłowej (IChP) wskali wielkolaboratoryjnej, wprocesie polikondensacji utleniającej 2,6-dimetylofenolu, wobecności kompleksu bromku miedzi(II) zmorfoliną jako katalizatorem (PPO-IChP). Wykazano, że mieszaniny PPO/HIPS, niezależnie od rodzaju PPO, są mieszalne wstanie amorficznym, oczym świadczy wystąpienie tylko jednej wartości temperatury zeszklenia oznaczonej metodami różnicowej kalorymetrii skaningowej (DSC) oraz dynamiczno-mechanicznej analizy termicznej (DMTA). Homogeniczność mieszanin potwierdzono również metodą skaningowej mikroskopii elektronowej (SEM). Mieszanina PPO-IChP/HIPS charakteryzowała się znacznie większą udarnością jak iwiększym wydłużeniem względnym przy zerwaniu niż mieszanina PPO-h/HIPS. Rodzaj zastosowanego PPO nie wpływał znacząco na wartość temperatury ugięcia pod obciążeniem (HDT) oraz wytrzymałość na rozciąganie izginanie badanych mieszanin. PPO otrzymany wIChP oraz jego mieszanina zHIPS wporównaniu zPPO-h iPPO-h/HIPS charakteryzowały się nieznacznie większą odpornością termiczną.The structures and thermal and mechanical properties of poly(phenylene oxide) (PPO) blends with high impact polystyrene (HIPS) were investigated. Two types of PPO were used: commercial one and the other prepared in Industrial Chemistry Research Institute (ICRI) in large laboratory scale process of oxidative polycondensation of 2,6-dimethylphenol, in the presence of complex of copper(II) bromide with morpholine as acatalyst (PPO-IChP). It has been proved that PPO/HIPS blends are miscible in amorphic state, independently on PPO type, because they show the single glass transition temperature, determined by differential scanning calorimetry (DSC) and dynamic mechanical thermal analysis (DMTA). Homogeneity of the blends was confirmed by scanning electron microscope (SEM) method. The PPO-IChP/HIPS blend showed significantly higher impact strength and relative elongation at break than PPO-h/HIPS one. The type of PPO used did not influence alot heat distortion heat deflection temperature (HDT) as well as tensile or flexural strength of the blends investigated. PPO-IChP and PPO-IChP/HIPS blend showed aslightly better thermal stability than PPO-h and PPO-h/HIPS blend