An opportunity cost approach for job assignment in a scalablecomputing cluster

A new method is presented for job assignment to and reassignment between machines in a computing cluster. Our method is based on a theoretical framework that has been experimentally tested and shown to be useful in practice. This “opportunity cost” method converts the usage of several heterogeneous resources in a machine to a single homogeneous “cost.” Assignment and reassignment are then performed based on that cost. This is in contrast to traditional, ad hoc methods for job assignment and reassignment. These treated each resource as an independent entity with its own constraints, as there was no clean way to balance one resource against another. Our method has been tested by simulations, as well as real executions, and was found to perform well     

The value of precise preoperative localization of colonic arteriovenous malformation in childhood

Massive hemorrhage from the gastrointestinal tract in a 12-yr-old boy caused by a congenital atypically located colonic arteriovenous malformation is described. Guided and "clean" resection of the involved colon was possible due to preoperative selective angiography, which proved to be the most efficient diagnostic tool. Histologic documentation of this rare pathology in childhood is presented, and the classification and features of the disease are briefly reviewed.     

On the Evolution Complexity of Design Patterns

Software co-evolution can be characterised as a way to “adjust” any given software implementation to a change (“shift”) in the software requirements. In this paper, we propose a formal definition of evolution complexity to precisely quantify the cost of adjusting a particular implementation to a change (“shift”) in the requirements. As a validation, we show that this definition formalises intuition about the evolvability of design patterns.     

Combatting sexual harassment.

Comments that S. Riger's (see record 1991-27670-001) overemphasis on presumed gender-biased definitions and on changing legislation and organizational policy related to sexual harassment (SH) detracts from her aim of promoting the growth and development of women in a changing society. Interventions are needed for modifying the social atmosphere that encourages SH and the educational procedures designed to help women recognize and combat SH. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Emotional support and suicide prevention through the Internet: A field project report

The Internet can be efficiently exploited to help people in severe emotional distress, including those contemplating suicide. Based on this premise and guided by various psychological principles that characterize Internet communication and behavior, on the one hand, and by factors related to the provision of emotional support, on the other, an Israeli project with the Hebrew acronym SAHAR was established. The idea behind SAHAR was to initiate an anonymous, confidential online environment that would attract people in a crisis situation and offer them a listening ear, mental support, and warmth, provided by anonymous, skilled helpers. At the heart of this exclusively online service is a content-rich Hebrew website (http://www.sahar.org.il) that provides relevant and continuously updated information for people in need. Accessed through the site, SAHAR offers, in addition, personal communication to users through synchronous and asynchronous support. For group communication, SAHAR provides online forums (a chat room will soon be launched). The website is accessed more than 10,000 times a month, or 350 times a day, a considerable number relative to Israel’s small population. Approximately 1000 personal contacts with SAHAR itself take place, each month, of which at least a third of the distressed users are clearly suicidal. The forums receive over 200 new messages a day. SAHAR on numerous occasions has participated in rescue operations of individuals who threatened to commit suicide or were actually in the process of trying. In many other cases, a supportive conversation or a referral to appropriate help resources prevented hasty decisions by highly distressed, desperate people contemplating suicide. Feedback by users also indicates the success of SAHAR as a unique psychological application on the Internet.     

A new approach for approximating node deletion problems

We present a new approach for approximating node deletion problems by combining the local ratio and the greedy multicovering algorithms. For a function , our approach allows to design a 2+max_v∈V(G)logf(v) approximation algorithm for the problem of deleting a minimum number of nodes so that the degree of each node v in the remaining graph is at most f(v). This approximation ratio is shown to be asymptotically optimal. The new method is also used to design a 1+(log2)(k−1) approximation algorithm for the problem of deleting a minimum number of nodes so that the remaining graph contains no k-bicliques.     

MEG source localization using an MLP with a distributed output representation

We present a system that takes realistic magnetoencephalographic (MEG) signals and localizes a single dipole to reasonable accuracy in real time. At its heart is a multilayer perceptron (MLP) which takes the sensor measurements as inputs, uses one hidden layer, and generates as outputs the amplitudes of receptive fields holding a distributed representation of the dipole location. We trained this Soft-MLP on dipolar sources with real brain noise and converted the network's output into an explicit Cartesian coordinate representation of the dipole location using two different decoding strategies. The proposed Soft-MLPs are much more accurate than previous networks which output source locations in Cartesian coordinates. Hybrid Soft-MLP-start-LM systems, in which the Soft-MLP output initializes Levenberg-Marquardt, retained their accuracy of 0.28 cm with a decrease in computation time from 36 ms to 30 ms. We apply the Soft-MLP localizer to real MEG data separated by a blind source separation algorithm, and compare the Soft-MLP dipole locations to those of a conventional system.     

Recovery of surface bacteria from and surface sanitization of cantaloupes

Practical, effective methods that could be implemented in a food service establishment (restaurant or delicatessen) for the surface sanitization of cantaloupes were microbiologically evaluated. Cantaloupes (Cucumis melo L. var. reticulates) were immersed in an inoculum containing Salmonella enterica serovar Poona or Pantoea agglomerans at ca. 10(4) to 10(5) CFU/ml. An efficient method for the recovery of bacteria from the cantaloupe surface was developed and validated. The method consisted of washing the entire melon with Butterfield's buffer containing 1% Tween 80 in a plastic bag placed inside a plastic pail affixed to an orbital shaker. Levels of S. enterica Poona recovered by washing the entire melon were significantly higher than those recovered by the more common laboratory method of blending the rind. P. agglomerans can be used as a non-pathogenic proxy for S. enterica Poona. A three-compartment surface sanitization method consisting of washing with an antimicrobial soap solution, scrubbing with a brush in tap water, and immersion in 150 ppm of sodium hypochlorite reduced the initial level of recoverable viable bacteria by 99.8%. When examined separately, scrubbing with a vegetable brush in tap water, washing with soap, and dipping in chlorine were found to reduce the bacterial load by 70, 80, and 90%, respectively.     

Experimental model aid for planar design of transistor characteristics in integrated circuits

A two-transistor lumped model is used to describe the main features of transistors' two dimensional action. The model provides a first order correction to the ideal one dimensional transistor gain due to the effect of the emitter periphery. The correction is given in terms of a single parameter which can be experimentally evaluated for a fixed diffusion process. This makes the model a practical tool in I.C. transistor layout design. Experimental virification of the model is presented. Finally, implication to gain and cutoff frequency falloff due to lateral injection at high current is suggested.