Feasibility Study of an Automated Tool for Identifying the Implications of Changes in Construction Projects

Because of the fragmented nature of project information, decisions on changes in construction projects are usually based on project design instead of project requirements. This research proposes a new approach for coping with changes in construction projects: A change control tool (CCT) that will identify implications of a change as soon as it is proposed. The tool will ensure that the stakeholders involved in the decision process in which change proposals are evaluated will know in advance if a change could cause the project to stray from its original goals, as expressed in the requirements. The proposed CCT uses the building program as a link between client requirements and the building design and traces the different relationships that exist between the requirements in the project. The relationships are traced using requirement traceability capabilities on the level of a specific space in the project and on the level of the entire project. A preliminary CCT model was developed and pilot studies implementing the model have been conducted. The pilot studies have given positive results, indicating that the CCT could identify the scope of the proposed changes’ implications.     

Using the KBTA method for inferring computer and network security alerts from time-stamped,raw system metrics

In this study, we propose a new approach for detecting previously unencountered instances of known classes of malicious software based on their temporal behavior. In the proposed approach, time-stamped security data are continuously monitored within the target computer system or network and then processed by the knowledge-based temporal abstraction (KBTA) methodology. Using KBTA, continuously measured data (e.g., the number of running processes) and events (e.g., installation of a software) are integrated with a security-domain, temporal-abstraction knowledge-base (i.e., a security ontology for abstracting meaningful patterns from raw, time-oriented security data), to create higher-level, time-oriented concepts and patterns, also known as temporal abstractions. Automatically-generated temporal abstractions can be monitored to detect suspicious temporal patterns. These patterns are compatible with a set of predefined classes of malware as defined by a security expert employing a set of time and value constraints. The new approach was applied for detecting worm-related malware using two different ontologies. Evaluation results demonstrated the effectiveness of the new approach. The approach can be used for detecting other types of malware by updating the security ontology with new definitions of temporal patterns.     

Total knee arthroplasty in the elderly: patients'' self-appraisal 6 and 12 months postoperatively

The classic goals of nutritional support have been to provide for the patient's ongoing nutritional needs and to preserve endogenous tissues from further catabolism. It is becoming increasingly clear that it also is possible to modulate metabolic and pathologic processes through the use of specific nutrients and metabolites and even the route by which nutrition is provided. This article discusses what is and is not known about the nutritional requirements of critically ill dogs and cats and some of the specific nutrients that are being used to enrich formulas for critically ill patients.     

Modeling building projects as a basis for change control

Changes made in building projects during their design and execution are a major cause for delays, cost overruns and deviations from performance requirements. The impact of changes on the project often becomes clear only after their implementation in the project. At that stage it is difficult to make adjustments or consider alternatives. A timely recognition, by the project team, of the implications of proposed changes can lead to a reconsideration of the changes, so that the completed project would still meet the client's objectives.This paper presents an ongoing research project for the development of a model of building projects, as a basis for change control. The model facilitates an automatic identification of the possible consequences of changes when they are first proposed, prior to their implementation in the design and planning of the project. The model utilizes available sources of project information in order to identify the impact of changes on the primary client objectives of cost, schedule and performance.The proposed model's feasibility was examined through its application in a case-study. The model was used to identify, in retrospect, the possible impact of proposed changes in a case study of a building project. The consequences of different change scenarios were quickly identified by tracing the relationships between the elements of the project. In reality, these consequences became clear only after the changes were fully implemented.     

Validation of the 36-item short-form Health Survey (Hebrew version) in the adult population of Israel

OBJECTIVES: In the past few years, the SF-36 Health Survey has drawn considerable attention from researchers in non-English-speaking countries. This report contributes to the growing body of literature on this instrument by reporting the results of a national study conducted in Israel. The study examined the psychometric properties of the Hebrew translation based on a sample of the adult population of Israel and evaluated the results from a cross-national perspective. METHODS: The sample included 2,030 adults drawn from the Jewish population, aged 45 to 75 years. The SF-36 Health Survey was administered in face-to-face interviews as part of a broader health study. RESULTS: The pattern of correlations among items and the internal consistency scores pointed to high reliability. Confirmatory factor analysis using the Amos 3.61 program supported the hypothesized factorial structure. Specifically, the items clustered around eight health dimensions, as was found in studies in other societies. Clear and statistically significant differences in the SF-36 Health Survey scores were found among age groups and population groups distinguished by the degree of chronic health problems. CONCLUSIONS: Results of the analysis indicate that the instrument provided an appropriate measure of general health status. The findings clearly indicate that the translation into the Hebrew language and the application of the instrument to a culturally heterogeneous population did not diminish the qualities of the instrument. They also point to certain items that might be modified to reduce problems of synonimity and embeddedness.     

Detection of malicious code by applying machine learning classifiers on static features: A state-of-the-art survey

This research synthesizes a taxonomy for classifying detection methods of new malicious code by Machine Learning (ML) methods based on static features extracted from executables. The taxonomy is then operationalized to classify research on this topic and pinpoint critical open research issues in light of emerging threats. The article addresses various facets of the detection challenge, including: file representation and feature selection methods, classification algorithms, weighting ensembles, as well as the imbalance problem, active learning, and chronological evaluation. From the survey we conclude that a framework for detecting new malicious code in executable files can be designed to achieve very high accuracy while maintaining low false positives (i.e. misclassifying benign files as malicious). The framework should include training of multiple classifiers on various types of features (mainly OpCode and byte n-grams and Portable Executable Features), applying weighting algorithm on the classification results of the individual classifiers, as well as an active learning mechanism to maintain high detection accuracy. The training of classifiers should also consider the imbalance problem by generating classifiers that will perform accurately in a real-life situation where the percentage of malicious files among all files is estimated to be approximately 10%.     

Application of new 13C n.m.r. techniques to the study of products from catalytic hydrodeoxygenation of SRC-II liquids

A middle-heavy SRC-II distillate (b.p. 230–455 °C), containing 3.0 wt% of oxygen, has been studied by means of ¹³C n.m.r. at 75, 100 and 125 MHz. The magnetization refocussing techniques INEPT and J-resolved two-dimensional Fourier transform have been utilized to demonstrate methods by which resonance line multiplicities may be determined in complex liquid mixtures. Products derived from the above coal liquid by hydrodeoxygenation at temperatures from 200 to 370 °C, using sulphided Co—Mo and Ni-W catalysts, were also examined. The fraction of aromatic carbon in the hydrotreated liquids was found to correlate directly with their C/H atomic ratio and inversely with the hydrogen content. Comparison of O/C atomic ratios with f_a values for these liquids indicates that hydrogen uptake < 260 °C is associated primarily with hydrogenolytic oxygen removal without attendant ring hydrogenation, while at temperatures between 260 and 350 °C hydrodeoxygenation is accompanied by ring hydrogenation and dealkylation reactions.     

A distributed architecture for efficient parallelization and computation of knowledge-based temporal abstractions

Today, data storage capabilities as well as computational power are rapidly increasing. On the one hand, this improvement makes it possible to generate and store a great amount of temporal (time-oriented) data for future query, analysis and discovery of new knowledge. On the other hand, systems and experts are encountering new problems in processing this increased amount of data. The rapid growth in stored time-oriented data necessitates the development of new methods for handling, processing, and interpreting large amounts of temporal data. One approach is to use an automatic summarization process based on predefined knowledge, such the Knowledge-Based Temporal-Abstraction (KBTA) method. This method enables one to summarize and reduce the amount of raw data by creating higher level interpretations based on predefined domain knowledge. Unfortunately, the task of temporal abstraction is inherently computationally expensive, especially when an enormous volume of multivariate data has to be handled and when complex patterns need to be considered. In this research, we address the scalability problem of a temporal-abstraction task that involves processing significantly large amounts of raw data. We propose a new computational framework, the Distributed KBTA (DKBTA), which efficiently distributes the abstraction process among several parallel computational nodes, in order to achieve an acceptable computation time. The DKBTA framework distributes the temporal-abstraction process along one or more computational axes, each of which enables parallelization of one or more temporal-abstraction tasks into which the main temporal-abstraction task is decomposed, such as by different subject groups, concepts types, or abstraction types. We have implemented the DKBTA framework and have evaluated it in a preliminary fashion in the medical and the information security domains, with encouraging results. In our small-scale evaluation, only distribution along the subjects axis and sometimes along the concept-type axis seemed to consistently enhance performance, and only for computations involving individual subjects and not functions of sets of subjects; but this observation might depend on the number of processing units. Additionally, since the communication between the processing units was based on the TCP protocol, we could not observe any speedup even when using two processing units on the same machine. In our further evaluations we plan to use a shared memory architecture in order to exchange data between processing units.     

Chromosome sensitivity to bleomycin-induced mutagenesis in lymphocytes from colorectal cancer patients under 40 years of age

PURPOSE: The incidence of colorectal cancer in young adults (under 40 years of age) is rare. The reason for the occurrence in these patients may lie in their genetic background. METHODS: We studied chromosomal fragility in peripheral blood lymphocytes of patients under the age of 40 with large bowel cancer. Lymphocytes from 24 subjects were examined: 10 untreated large bowel cancer patients under the age of 40 and 14 age-matched and sex-matched controls. RESULTS: The mean number of spontaneous chromosomal breaks per cells (b/c) was significantly higher in the right-sided large bowel cancer patients (0.23 +/- 0.12 b/c) compared with the control group (0.09 +/- 0.04 b/c; P < 0.01), but with no significant difference between the left-sided colorectal cancer patients and the control group. Lymphocytes exposed to the radiomimetic agent, bleomycin, were arrested in methaphase and analyzed for chromosome fragility. Mean chromosome breaks per cell in the left-sided colorectal cancer patients (1.60 +/- 0.49 b/c) were significantly higher than in either the controls (0.72 +/- 0.31 b/c; P < 0.001) or the right-sided, large bowel cancer patients (0.91 +/- 0.24 b/c; P < 0.05). CONCLUSIONS: The increased spontaneous chromosomal breaks in the right colon, as opposed to the increased mutagen-induced chromosomal breaks in the left colon, might indicate that in young colon cancer patients the occurrence of right-sided colon cancer is more likely to be genetically determined, whereas in left-sided colon cancer, environmental carcinogens might play a greater role.