A modelling approach to the evalution of computer system performance

Imperial Users onl

Generating target system specifications from a domain model using CLIPS

The quest for reuse in software engineering is still being pursued and researchers are actively investigating the domain modeling approach to software construction. There are several domain modeling efforts reported in the literature and they all agree that the components that are generated from domain modeling are more conducive to reuse. Once a domain model is created, several target systems can be generated by tailoring the domain model or by evolving the domain model and then tailoring it according to the specified requirements. This paper presents the Evolutionary Domain Life Cycle (EDLC) paradigm in which a domain model is created using multiple views, namely, aggregation hierarchy, generalization/specialization hierarchies, object communication diagrams and state transition diagrams. The architecture of the Knowledge Based Requirements Elicitation Tool (KBRET) which is used to generate target system specifications is also presented. The preliminary version of KBRET is implemented in the C Language Integrated Production System (CLIPS)

Applying End User Software Product Line Engineering for Smart Spaces

Smart spaces are physical environments equipped with pervasive technology that sense and react to human activities and changes in the environment. End User Development (EUD) skills vary significantly among end users who want to develop software applications for their smart spaces. This paper presents a systematic approach for adopting reuse in EUD for smart spaces by using Software Product Line (SPL) concepts. End User (EU) SPL designers develop EU SPLs for smart spaces whereas end users derive their individual smart space applications from these SPLs. In particular, this paper presents a systematic approach for EU SPL designers to develop EU SPLs and end users to derive software applications for their spaces, an EUD environment that supports EU SPL development and application derivation, and a testing approach for testing EU SPLs and derived applications

Parents’ Perception of School Violence, Awareness of Risk Factors, and School Safety: An Ecological Perspective

Parents’ concerns about school violence and school safety have been documented in many research studies (Diaz-Vicario & Sallan, 2017; Hundeloh & Hess, 2003). Understanding parents’ perceptions of school safety can be an important issue that will guide teachers (Bosworth, Ford, & Hernandaz, 2011), administrators and staff (Heisterkamp, & Fleming, 2011), and legislators (Elliott, 2015) in setting strategies to enhance school safety and school climate. The purpose of this study is to identify factors that contribute to parents’ views of school safety. Based on existing literature, this study developed a model of one main endogenous variable -- feelings of instructional safety -- and seven additional exogenous and endogenous variables -- awareness of bulling behavior, awareness of school violence, parent visits school, communicating perspective, experience with violence, knowledge of risk, resources and school measures. A total of 403 parents who reside in the southern part of Illinois participated in the survey. Path analysis with exploratory modifications was used to examine the study model and the study hypotheses. The study findings suggested parents’ visits to school and parents’ experience with violence had statistically significant direct effects on their awareness of school violence, which had a significant direct effect on parents’ feelings of instructional safety. Although exploratory, this study provided important insights on school violence, school safety and school climate, and implications for future research in this area are discussed

Floristic diversity and vegetation analysis of Brassica nigra (L.) Koch communities

The floristic composition and species diversity of Brassica nigra communities were investigated in Beni Suef Governorate, Egypt. In 46 stands, a total of 49 species belonging to 42 genera and 18 families were recorded. Vegetation classification and ordination distinguished seven groups: two in reclaimed land only, three groups in old cultivated land only, and two that occurred in both types of land. The species that dominated these groups were Brassica nigra, Sonchus oleraceus, Beta vulgaris, Cichorium endivia, Euphorbia helioscopia and Anagallis arvensis. The highest species diversity was mainly in groups from reclaimed land, and in wheat compared to other crops. Edaphic factors, especially soil texture, CaCO3 and organic carbon, contributed significantly to explaining the distribution of some weed species, but not with that of B. nigra. The allelopathic potential of Brassica nigra reported in previous studies did not seem to play a role in community composition.Keywords: allelopathy, Brassica nigra, vegetation, TWINSPAN, weed diversit

Modeling behavioral design patterns of concurrent objects

ABSTRACT Object-oriented software development practices are being rapidly adopted within increasingly complex systems, including reactive, real-time and concurrent system applications. While data modeling is performed very well under current objectoriented development practices, behavioral modeling necessary to capture critical information in real-time, reactive, and concurrent systems is often lacking. Addressing this deficiency, we offer an approach for modeling and analyzing concurrent object-oriented software designs through the use of behavioral design patterns, allowing us to map stereotyped UML objects to colored Petri net (CPN) representations in the form of reusable templates. The resulting CPNs are then used to model and analyze behavioral properties of the software architecture, applying the results of the analysis to the original software design

(R)-1-Phenyl­ethanaminium (S)-4-chloro­mandelate

The absolute configuration of the title complex, C8H12N+·C8H6ClO3 − or [R-C6H5C(H)CH3NH3][S-4-ClC6H4C(H)(OH)CO2], has been confirmed by the structure determination. In the crystal structure, inter­molecular O—H⋯O and N—H⋯O hydrogen bonds form a two-dimensional network perpendicular to the c axis

Design, synthesis, crystal structures and biological evaluation of some 1,3-thiazolidin-4-ones as dual CDK2/EGFR potent inhibitors with potential apoptotic antiproliferative effects

A series of novel thiazolidine-4-one derivatives was synthesized by reacting 1,4-disubstituted hydrazine carbothioamides with diethyl azodicarboxylate. The structures were confirmed by spectroscopic data as well as single-crystal X-ray analyses. The antiproliferative activity of the synthesized compounds was investigated against four human cancer cell lines using an MTT assay. Compounds 5d, 5e, and 5f revealed the most potent antiproliferative activity with GI$_{50}$ values ranging from 0.70 µM to 1.20 µM, compared to doxorubicin GI$_{50}$ value = 1.10 µM. Compounds 5d, 5e, and 5f were further investigated for their inhibitory activities against CDK2 and EGFR as potential targets for their molecular mechanism. Compounds 5e and 5f have showed potent inhibitory activity to CDK2 enzyme with IC$_{50}$ values of 18 and 14 nM, which is more potent than the reference dinaciclib (IC$_{50}$ = 20 nM). Moreover, compounds 5e and 5f were the most potent EGFR inhibitors, with IC$_{50}$ values of 93 and 87 nM, respectively, compared to the reference erlotinib (IC$_{50}$ = 70 nM). In addition, the most potent derivatives were tested for their apoptotic activity against caspases 3, 8, and 9, and the results showed that compounds 5d, 5e, and 5f revealed a greater increase in active caspases 3,8 and 9 than doxorubicin. Also, compounds 5d, 5e, and 5f elevated cytochrome C levels in the MCF-7 human breast cancer cell line by about 15.5, 15.8, and 16.5 times, respectively. Finally, a molecular docking study was performed to investigate the binding sites of these compounds within the active sites of CDK2 and EGFR targets, and the results confirmed that the most potent CDK2 and EGFR inhibitor 5h also have showed the highest docking score