Abstract. Rainstormdamage caused by the malfunction of urban drainage systems and water intrusion due to defects in the building envelope can be considerable. Little research on this topic focused onthe collection ofdamagedata, the understanding ofdamage mechanisms andthe deepening ofdata analysis methods. In this paper, the relative contribu- tion of different failure mechanisms to theoccurrenceofrainstormdamage is investigated, as well as the extent to which these mechanisms relate to weather variables. For a case study in Rotterdam, the Netherlands, a property level homeinsurance database of around 3100 water-related dam- age claims was analysed. The records include comprehen- sive transcripts of communication between insurer, insured anddamage assessment experts, which allowed claims to be classified according to their actual damage cause. The results show that roof and wall leakage is the most frequent failure mechanism causing precipitation-related claims, followed by blocked roof gutters, melting snow and sewer flooding. Claims related to sewer flooding were less present in thedata, but are associated with significantly larger claim sizes than claims in the majority class, i.e. roof and wall leakages. Rare events logistic regression analysis revealed that maximum rainfall intensity and rainfall volume are significant predic- tors for theoccurrence probability of precipitation-related claims. Moreover, it was found that claims associated with rainfall intensities smaller than 7–8 mm in a 60-min win- dow are mainly related to failure processes in the private do- main, such as roof and wall leakages. For rainfall events that exceed the 7–8 mm h −1 threshold, the failure of systems in the public domain, such as sewer systems, start to contribute considerably to the overall occurrence probability of claims. The communication transcripts, however, lacked information
The route ofthe ship during sampling andthe positions marked by the MMOs are recorded using a tablet with an inbuilt GPS and running the application MyTracks (https://my-tracks.pt.aptoide.com). This application regis- ters, among other variables, the date and time (programmed for GMT + 0), the speed (in m/s) and direction (in °) ofthe vessel andthe GPS coordinates (in decimal format, WGS84 coordinate system). The recommended record- ing settings are maintained: recording every 10 seconds or 10 metres (whichever the smallest) and with minimum precision of 50 m. These settings were occasionally changed in order to overcome battery life issues. The applica- tion, although working efficiently at sea, on rare occasions, generates errors in the date and time recording (with the time going forwards and backwards). This issue demands a careful verification process during data entry. An adaptation ofthe protocol was made during the first year ofthe project (2012 campaigns), in which a Garmin GPS (with similar settings) was used, with positions being annotated by hand and later imported into Microsoft Excel spreadsheets. During this year, the use of alternative survey stands (e.g. deck ofthe ship) was explored. Besides dataon cetacean occurrences, information about theweather conditions, marine traffic andthe presence of other pelagic megafauna is also collected. To record weather conditions, observers assess sea state (using the Douglas scale), wind speed (using the Beaufort scale), visibility (on a categorical scale of values from 1–10 thus covering visibility ranges from 0 m to more than 50000 m, estimated basedonthe definition ofthe horizon line and ref- erence points at a known range, e.g., ships with an AIS system) andtheoccurrenceof rain. This information is registered at the beginning and end of each survey leg (a survey leg being a continuous period of sampling) and every time there are significant changes in the conditions. For the marine traffic, small and big vessels (less than and over 20 m in length), detected with or without binoculars, all around the ship´s position, are registered at the beginning and end of each survey, at every sighting of cetacean species and every hour. For pelagic megafauna other than cetaceans, thedata are always collected opportunistically, as sampling effort is dedicated uniquely to cetacean species. In these cases, only taxonomic information andthe number of individuals (as well as optional comments about the sighting, e.g., animal behaviours, presence of calves or others) are registered. Whenever MMOs cannot gain access to the survey stand (e.g. during safety drills, manoeuvres) or when weather conditions are unfavourable for cetacean monitoring (e.g. at Beaufort or Douglas values > 4, visibility < 1 km or heavy rain), the sampling effort stops and any data collected until effort resumes is considered opportunistic (off-effort).
Abstract. Abrupt drought–flood change events caused by atmospheric circulation anomalies have occurred frequently and widely in recent years, which has caused great losses and casualties in China. In this paper, we focus on investigating whether there will be a rainfall occurrence with higher in- tensity after a drought period in the Huang–Huai–Hai River basin. Combined with the Chinese climate divisions andthe basin’s DEM (digital elevation model), the basin is divided into seven sub-regions by means of cluster analysis ofthe basin meteorological stations using the self-organizing map (SOM) neural network method. Basedonthe daily precip- itation dataof 171 stations for the years 1961–2011, the changes of drought times with different magnitudes are ana- lyzed, andthe number of consecutive days without precipita- tion is used to identify the drought magnitudes. The first pre- cipitation intensity after a drought period is analyzed with the Pearson-III frequency curve, then the relationship be- tween rainfall intensity and different drought magnitudes is observed, as are the changes of drought times for different years. The results ofthe study indicated that theoccurrence times of different drought levels show an overall increasing trend; there is no clear interdecadal change shown, but the spatial difference is significant. (2) As the drought level in- creases, the probability of extraordinary rainstorm becomes lower, andthe frequency ofoccurrenceof spatial changes in different precipitation intensities vary. In the areas I and II, as the drought level increases, theoccurrence frequency of different precipitation intensities first shows a decreasing
Let us suppose that n travelers depart from country A to country B, each of which with a probability p of being infected by an emerging infectious disease occurring in A. The proportion of infected persons (popu- lation prevalence) in A would give a rough estimate for probability p. An additional assumption is that the probability p that a passenger is infected does not depend onthe probability that another passenger gets infected in the country of origin. Approxi- mately, there is a probability (1 – p) n that all
Nanoparticles as a new generation of materials are used in many fields. The basic methods for their preparation are the top- down and bottom-up techniques. The essence ofthe top-down technique consists in grinding the material to particles with nano dimensions, while the bottom-up technique assumes making structures from molecules or single atoms [1,2]. According to a method recently developed, the nanoparticles of metal oxides are produced through anodic dissolution of metals . There are also thermal methods of obtaining metal nanoxides [4-7].
Table 2 gives the results of mechanical tests carried out onthe low-alloy cast steel with additions of vanadium and compares them with the results of previous studies made on this cast steel (designated as P1 in Tables 1 and 2) subjected to heat treatment recommended by the respective standard .
Enhanced recovery is so important in the petroleum industry that the location ofthe producer well is chosen with the secondary well (injection well) in mind. As mentioned before, efforts to enhance recovery are costly and are dependent upon the state ofthe economy andthe potential oil recovery volume. Consequently, repeated monitoring of a reservoir is essential to choose the best locations for the injection wells. The idea is to design an optimal distribution of injection wells so as to optimize long-term production. There are several types of wells: wildcat well, rank wildcat well, step-out well, pro- ducer well, injection well, etc. Since there are different steps in the process of obtaining oil, wells are classified broadly as exploratory wells and development wells. Examples of exploratory wells are wildcat wells (drilled a mile or more from an area of existing oil production) and rank wildcat wells (drilled in an area where there is no existing produc- tion). If the exploratory drilling proves successful, the company starts to drill step-out wells (also included in the exploratory well category). After the oil field has been delin- eated, the company starts to drill production wells within the known extent ofthe field. Every well drilled inside the known extent ofthe field is called a development well (Hyne (2001)). The development well category includes producer wells and injection wells (re- call that injection wells are drilled to enhance oil recovery). Different categories of wells have different probabilities of finding oil. On average, rank wildcat exploratory wells have lower success ratio than step-out wells. An oil company can rank wells in terms of probability, even in the face of uncertainty. The American Petroleum Institute reported that in 2000 the success rate for wildcat wells was 39% (Hyne (2001)). Note that an unsuccessful drilling is classified as a dry hole in both exploratory and development well categories.
Within the natural park a rich flora including a significant number of rarities such as: Lysimachia nemorum L., Ranunculus thora L., Silene rupestris L., Salix bicolor Willd., Trifolium lupinaster L., Woodsia alpina (Bolton) Gray, Sagina apetala Ard., Rhinanthus alectorolophus (Scop.) Pollich and so onand a great number of dacic elements such as: Gymnadenia carpatica (Zapał.) Teppner & E. Klein, Heracleum carpaticum Porcius, Pulmonaria filarszkyana Jáv., Poa rehmannii (Asch. & Graebn.) K. Richt, Cochlearia borzaeana (Coman & Nyár.) Pobed., Silene zawadzkii Herb. and so on can be found.
Test bed to investigation of porosity ofthe alloy consisted ofthe NEOPHOT 32 metallographic microscope equipped with high resolution camera connected to computerized system of image analysis. Next, with use ofthe MULTISCAN program there were performed photos ofthe investigated specimens (Fig. 5). Successive stage consisted on generation, with use ofthe image analyzer system, an image of specimens’ photos showing areas of porosity and contraction cavities only, on base of which the software could calculate surface area ofthe porosities and contraction cavities.
In the paper the 2D task concerning the continuous casting technology is discussed. Onthe basis ofthe knowledge of temperature history at the selected set ofthe points from the casting domain the boundary heat flux is identified [5, 6, 7]. The identification ofthe boundary heat flux in the primary cooling
To tackle these problems, in this paper we rely on a large panel of matched employer- employee data. Basedon administrative files maintained by the federal government in Brazil (Rela¸c˜ao Anual de Informa¸c˜oes Sociais - RAIS ), thedata provides information on every single employment relationship that all registered employers have during the year. Thedata set is rich in that it contains information on wages andonthe characteristics of workers (sex, age, education), establishments (industry, size), and jobs (occupation, tenure). Its census nature allows precise computations ofthe share of women within the segregation dimensions of interest: occupation, industry, establishment, and job cell (i.e., occupation within establishment). This a strength of this study as compared to the previous literature, which had to rely on small samples of workers or a limited set of occupations to calculate the proportion of females along these dimensions. The longitudinal aspect ofthedata for workers and establishments also allows us to deal with distinct forms of unobserved heterogeneity in wage regressions. One ofthe main contributions of this paper is the incorporation of fixed effects for workers, firms, and workers-firms matches in the estimation ofthe segregation effects of interest onthe gender wage gap. To the best of our knowledge, this is the first paper that does that in the literature. 2
The tested material consisted of samples ofthe X2CrNiMoN22-5-3 ferritic-austenitic duplex steel (Fig. 1a), which have been aluminised in FeAl powder at a temperature of 900 o C for 6 hours (Fig. 1b). The alloy powders used in the presented experiment were formed in the process of self- decomposition of high-aluminium alloy. As a result of this decomposition, basedon intermetallic phases of Fe-Al, the structure of a secondary solution was obtained. The chemical composition ofthe tested powder andofthe material subjected to aluminising is shown in Table 1. The oxidation rate ofthe examined materials under the isothermal conditions was determined on a LABSYS TM Setaram equipment. Dimensions ofthe examined samples were 4x3x2,5 mm. The oxidation process was carried out in accordance with the following parameters:
The work is a continuation of research onthe use of water mist cooling in order to increase efficiency ofthe die-casting process for aluminum alloys. The paper describes the multipoint sequential cooling system ofthe casting die and its computer control and monitoring. It also includes results ofthe tests and analysis of cooling methods during making ofthe casting. These methods differ from each other in the sequence of casting die cooling and cause effective changes in microstructure and mechanical properties of castings made of AlSi11 alloy. The study demonstrated that the use of multipoint sequential cooling with water mist affects the microstructure refinement and reduces the segregation in the cast as well as more than by 20% increases the mechanical properties of castings in the rough state. The study also demonstrates that the sequential cooling of casting die accelerates the cooling ofthe casting and shortens die-casting cycle.
Clustering is a central task for which many algorithms have been proposed. The task of finding a good cluster is very critical issues in clustering. Cluster analysis constructs good clusters when the members of a cluster have minimize distances (Intra-cluster distances are minimized or internal homogeneity) are also not like members of other clusters (Inter-cluster distances are maximized). Clustering algorithms can be hierarchical or partitional.
Low crop productivity is one ofthe major problems that are facing agricultural production in the Sudan. Low crop productivity in addition to high production costs, low prices and high taxes had all resulted in a general deterioration ofthe agricultural sector. This has contributed in converting agriculture from an attractive business to a repellent activity and caused many farmers to abandon agriculture and migrate to cities. The agricultural sector in the Sudan contributes to about 48% ofthe Gross Domestic Production (GDP) and to about 93% ofthe foreign currency earnings (Ministry of Finance and National Economy, 1996). It also employs about 65% ofthe labor force. Sorghum (Sorghum bicolor L.) is the major staple food crop in the Sudan. It is estimated that the annual consumption amounts to about 3.9 Million tons (Elsayed, 1999). It is cultivated in large areas that include both irrigated and rainfed. Farah, et al. (1997) reported that the area which is annually cultivated by sorghum is about 2.1 million ha, of which 80% is completely rain-fed, whereas the remainder is given supplementary irrigation throughout the growing season. The Gezira scheme contributes by 60% to the total irrigated production (Elsayed, 1999). Irrigated sorghum production is characterized by the use of disc harrows and ridgers for land preparation, improved varieties and fertilizers. However, yield per unit area in this sector is still very low 1400 kg ha -1 (Ibrahim, 1992). Great efforts had been put in the Gezira scheme to increase sorghum productivity which led to increase the average yield during the pervious seasons, this could be due to the high adoption rate ofthe recommended technical packages released by the Agricultural Research Corporation (ARC). Maize (Zea mays L.) is traditionally cultivated along the banks ofthe River Nile in the northern states and it is also cultivated in southern states. The area cultivated by maize in the Sudan during the period 1989- 1995 is estimated to be about 21,840 hectares (FAO, 1995). However, maize is classified today as a new promising crop in the irrigated projects of central and eastern Sudan. The average yield per unit area of sorghum and maize ofthe Sudan are very low compared to other areas in the world have the same weather conditions. Vertisols ofthe Gezira scheme
Regional differences found for catastrophic health spending basedon capacity to pay rela- tive to consumption were significant and did not follow a pattern linked to regional economic development. The Central Region showed the largest proportions of catastrophic spending, a region richer than the North andthe Northeast. Further work would be needed to pinpoint the reasons. As possible explanations, we suggest our finding that private health insurance policies do not protect households from catastrophic health spending. In fact, some private policies may even increase health expenses through their induced demand for specialized and costly medical ser- vices, which are not always covered by them. Brasília, the capital, presents a large number of senior public sector staff, who may be in special need of these services. It has also the highest per capita income in the country, which may add to the unexpected finding. This, in conjunction with towns established not long ago, where public health services might not have had enough time to be sufficiently organized may explain the high- er proportion of catastrophic health expenditure in this region ofthe country. Onthe other end ofthe scale, the two richest regions in the coun- try (South and Southeast) presented the lowest proportions of catastrophic spending, which is probably linked to better wages and a better es- tablished health system.
In Portugal, a lot of companies already found that they have more advantages on doing car renting contracts besides of buying an entire fleet, and already represents 15,6% of European Renting Market 1 . Renting is a flexible option which allows cost reductions, rationalization plans and passing of associated risks facing the car value – depreciation and used car sales. However, in the end ofthe contract the customers are sometimes surprised with extra costs from damages not included on vehicle normal usage. From the rental company side, we cannot say that they have extra costs but obviously they lose money on car sales.
Machine and tools elements made ofthe steel C90 and HS 6-5-2 immediately after the conventional hardening, need the tempering process. During the tempering, there is a transforma- tion of retained austenite into martensite and carbides release in martensite, what leads to the increase hardness ofthe high-speed steel, whereas in non-alloy steels tempering cause decrease the hardness.
In this paper chromium to 1,00% and copper to 1,50% influence at constant molybdenum content of about 1,50% onthe nodular cast iron with carbides microstructure has been presented. It was found, that as a result of synergic addition of above-mentioned elements there is the possibility obtaining an ausferrite in nodular cast iron with carbides castings. Conditions have been given, when in nodular cast iron with carbides at cooling at first in the form, then air-cooling austenite transformation to upper bainite, its mixture with lower bainite, martensite or ausferrite takes place. Transformations proceed during cooling andthe crystallization of cast iron have been determined andthe casting hardness has been presented.
Taking the above into consideration, for investigations the following alloys were selected: a hypereutectic AlSi17 silumin which was “enriched” with additions of ~3%Cu, ~1,5%Ni and ~1,5%Mg (added separately or jointly). A compilation ofthe examined silumins is given in Table 1.