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The graph signature : a scalable query optimization index for RDF graph databases using bisimulation and trace equivalence summarization
No full textQuerying large data graphs has brought the attention of the research community. Many solutions were proposed, such as Oracle Semantic Technologies, Virtuoso, RDF3X, and C-Store, among others. Although such approaches have shown good performance in queries with medium complexity, they perform poorly when the complexity of the queriesincreases. In this paper, the authors propose the Graph Signature Index, a novel and scalable approach to index and query large data graphs. The idea is that they summarize a graph and instead of executing the query on the original graph, they execute it on the summaries. The authors’ experiments with Yago (16M triples) have shown that e.g., a query with 4 levels costs 62 sec using Oracle but it only costs about 0.6 sec with their index. Their index can be implemented on top of any Graph database, but they chose to implement it as an extension to Oracle on top of the SEM_MATCH table function. The paper also introduces disk-based versions of the Trace Equivalence and Bisimilarity algorithms to summarize data graphs, and discusses their complexity and usability for RDF graph
Effect of introduction of furfural on asphalt binder ageing characteristics
No full textAsphalt oxidative ageing and excessive hardening are known causes of premature pavement
cracking. Asphalt ageing occurs mainly due to the oxidation of certain functional groups in
asphalt as well as the loss of the maltene phase disturbing colloidal stability and increasing
micellisation concentration. This in turn can cause large non-soluble asphaltene aggregates
which are typically suspended in the maltene solution and are stabilised by resin molecules to
flocculate. Flocculation can cause the asphalt to become stiffer and more brittle. It should be
noted that excessive hardening and brittleness of asphalt caused by oxidation during pavement
production and service life increase the susceptibility of asphalt pavements to cracking. Therefore,
reducing the extent of asphalt oxidation could increase pavement service life. Therefore,
it is imperative to reduce/delay asphalt oxidation in asphalt binder. There have been several
studies on delaying asphalt oxidation by introducing modifiers and anti-ageing additives. Furfural,
an organic compound derived from a variety of agricultural by-products, has been shown
to be a promising modifier for petroleum asphalt binders used in asphalt pavement. Accordingly,
this paper investigates the effect of introducing furfural as an antioxidant for asphalt by
evaluating the extent of oxidation ageing in asphalt specimens modified by 1%, 2% and 5%
furfural. To do so, furfural was introduced to asphalt and the level of change in physiochemical
and rheological properties of asphalt after specimens were exposed to short- and long-term
ageing was examined. Accordingly, performance characteristics of the base asphalt were compared
with those of furfural-modified asphalts using a rotational viscometer, Fourier transform
infrared spectroscopy and a dynamic shear rheometer to evaluate the rheological properties of
asphalt modified with furfural at different percentages. The study results showed that the addition
of furfural helped reduce the extent of oxidative ageing while enhancing high-temperature
performance of asphalt binder. Specifically, it was found that the 2% furfural modification had
the lowest ageing index after ageing, indicating an improvement in binder oxidative agein
Women’s behaviour in public spaces and the influence of privacy as a cultural value: The case of Nablus, Palestine
No full textArchitecture
Ghadban,Shadi:
J?rgensen,Karsten:The aim of this paper is to study how women’s privacy needs are met through the physical form
of public spaces in both old and new urban designs, using as a case study the city of Nablus,
Palestine, which has been significantly influenced by the culture of gender separation. The findings
will help develop a better understanding of the relationship between women’s privacy and the
physical form of public spaces and will enhance the development of public spaces that women can
use comfortably and actively to participate in the urban life. An environmental approach based on
the concept of behavioural setting was used to examine women’s privacy issues in the chosen
public spaces. Direct observations and questionnaires were used in the fieldwork, in addition to
interviews with women and relevant people who influence the women’s privacy. Maps (GIS),
sketches and SPSS techniques were used to interpret the data
Removal of organic Pollutants from wastewater using different treatment technologies
No full textBio-Technolog
Palestinian women’s satisfaction with reproductive health services at the health centers of the Health Work Committees, West Bank
No full textWe used qualitative and quantitative methods. Three focus groups discussions were conducted with women of different ages; in the north, middle and south of the West Bank. Face-to-face interviews were held with 72 stratified sample of women recruited from eight HWC’s women’s health clinics, using a piloted semi-structured questionnaire. The data was collected in August 2014, during one busy day for each health center. SPSS statistical package was used for data analysis. Oral permissions were elicited from women.Health Work Committees (HWC) is Palestinian development and health NGO. In addition to providing health education and capacity building services for women, the Women’s Health Program of HWC has been providing health services for women of all ages including preventive and curative care services. This study aims to improve the quality of the reproductive health services provided in the health centers of the HWC, through examining women’s satisfaction in areas related to the structural, technical and process measures of qualit
Potential application of renewable energy application at wastewater treatment plants in Palestine, three case studies
No full textThis paper assess the energy consumption and the removal efficiency of three wastewater treatment plants (WWTPs) in Palestine and explores the potential application of renewable energy with associated impacts on unit operations. National rules and regional guidelines for treated water are regulatory instruments for the construction approval of WWTPs in Palestine. Three urban WWTPs of various technologies were selected as case studies for the assessment. The technologies applied were conventional activated sludge with anaerobic sludge digestion, extended aeration and membrane bioreactor (MBR) serving Nablus-West, Al-Bireh and Altira; respectively. Analysis of collected data on the BOD5 removal were 96%, 98% and 99%; respectively. The removal efficiency of nitrogen reached 85% and 95% for Al-Bireh and Altira; respectively and not accounted for in Nablus-West WWTP. The energy required for both liquid and sludge lines was calculated based on the available data and correlated treatment efficacy. Results analysis revealed wide variations in the energy consumption among the three WWTPs. Altira MBR showed normal trends compared to published literature with 2.88 kWh/m3, of which 40% was consumed by the biological treatment stage. Al-Bireh WWTP consumed 1.86 kWh/m3 with 35% of the electrical consumption for biological stage, and 24% for the sludge line. Nablus-WWTP consumed 2.25 kWh/m3 with 62% of the energy consumed by the biological stage and 34% for sludge line. Underload operation below the design capacities, the specific energy consumption for Al-Bireh and Nablus-West WWTPs are contradicting common published data for activated sludge treatment systems. Use of renewable energy could assist in the reduction of the annual energy operational costs. Assessment of solar photovoltaic (PV) application could yield electricity sufficient for pump station facilities and cover 9%, 15%, and 1% of the energy demand respectively. PV installation at Nablus WWTP showed marginal impacts if connected off-grid or if combined heat and power are not operational until 2020, payback periods were estimated at 7.5 and 18.7 years; respectively
