A Generic Checkpoint-Restart Mechanism for Virtual Machines

It is common today to deploy complex software inside a virtual machine (VM). Snapshots provide rapid deployment, migration between hosts, dependability (fault tolerance), and security (insulating a guest VM from the host). Yet, for each virtual machine, the code for snapshots is laboriously developed on a per-VM basis. This work demonstrates a generic checkpoint-restart mechanism for virtual machines. The mechanism is based on a plugin on top of an unmodified user-space checkpoint-restart package, DMTCP. Checkpoint-restart is demonstrated for three virtual machines: Lguest, user-space QEMU, and KVM/QEMU. The plugins for Lguest and KVM/QEMU require just 200 lines of code. The Lguest kernel driver API is augmented by 40 lines of code. DMTCP checkpoints user-space QEMU without any new code. KVM/QEMU, user-space QEMU, and DMTCP need no modification. The design benefits from other DMTCP features and plugins. Experiments demonstrate checkpoint and restart in 0.2 seconds using forked checkpointing, mmap-based fast-restart, and incremental Btrfs-based snapshots

Performance Evaluation of Greenhouse Having Passive or Active Heating in Different Climatic Zones of India

Rosana G. Moreira, Editor-in-Chief; Texas A&M UniversityThis is a paper from International Commission of Agricultural Engineering (CIGR, Commission Internationale du Genie Rural) E-Journal Volume 9 (2007): Performance Evaluation of Greenhouse Having Passive or Active Heating in Different Climatic Zones of India. Manuscript EE 06 011. Vol. IX. May, 2007

Microwave photovoltage and photoresistance effects in ferromagnetic microstrips

We investigate the dc electric response induced by ferromagnetic resonance in ferromagnetic Permalloy (Ni80Fe20) microstrips. The resulting magnetization precession alters the angle of the magnetization with respect to both dc and rf current. Consequently the time averaged anisotropic magnetoresistance (AMR) changes (photoresistance). At the same time the time-dependent AMR oscillation rectifies a part of the rf current and induces a dc voltage (photovoltage). A phenomenological approach to magnetoresistance is used to describe the distinct characteristics of the photoresistance and photovoltage with a consistent formalism, which is found in excellent agreement with experiments performed on in-plane magnetized ferromagnetic microstrips. Application of the microwave photovoltage effect for rf magnetic field sensing is discussed.Comment: 16 pages, 15 figure

Attractive Potential around a Thermionically Emitting Microparticle

We present a simulation study of the charging of a dust grain immersed in a plasma, considering the effect of electron emission from the grain (thermionic effect). It is shown that the OML theory is no longer reliable when electron emission becomes large: screening can no longer be treated within the Debye-Huckel approach and an attractive potential well forms, leading to the possibility of attractive forces on other grains with the same polarity. We suggest to perform laboratory experiments where emitting dust grains could be used to create non-conventional dust crystals or macro-molecules.Comment: 3 figures. To appear on Physical Review Letter

Potential of heat pipe technology in nuclear seawater desalination

The official published version of this article can be found at the link below.Heat pipe technology may play a decisive role in improving the overall economics, and public perception on nuclear desalination, specifically on seawater desalination. When coupled to the Low-Temperature Multi-Effect Distillation process, heat pipes could effectively harness most of the waste heat generated in various types of nuclear power reactors. Indeed, the potential application of heat pipes could be seen as a viable option to nuclear seawater desalination where the efficiency to harness waste heat might not only be enhanced to produce larger quantities of potable water, but also to reduce the environmental impact of nuclear desalination process. Furthermore, the use of heat pipe-based heat recovery systems in desalination plant may improve the overall thermodynamics of the desalination process, as well as help to ensure that the product water is free from any contamination which occur under normal process, thus preventing operational failure occurrences as this would add an extra loop preventing direct contact between radiation and the produced water. In this paper, a new concept for nuclear desalination system based on heat pipe technology is introduced and the anticipated reduction in the tritium level resulting from the use of heat pipe systems is discussed

Comparative evaluation of the performance of online databases in answering toxicology queries

An evaluation of toxicology information resources is reported, comparing commercial online databases and a specialised in-house database. A mixed qualitative/quantitative approach, using ten test queries and detailed failure analysis was used. The main conclusions are: the in-house database is superior to any ‘general’ database in recall and precision; commercial databases are a useful complement, usually providing unique material; a range of databases should be used for good recall; for the commercial databases, complex search strategies are necessary, using the specific access points of each database; retrieval failures are due primarily to coverage, secondly to poor indexing of specific toxic effect. Detailed discussion is given of indexing policies and search strategies

A Study on the Influence of Customer Sales Promotion Tools Based on Customer Income

This study is important as it provides analysis regarding the influence of the total customer-centric promotion tools according to the total income status of the customers crucially. This study has formulated the basic approach to the topic and also prompted different considerable promotions. Aims and objectives are formulated as per the strategic customer-centric procedures that are relevant in pursuing the entire study. Moreover, a literature review has resulted in a critical analysis of the study, and in this study, the secondary qualitative analysis is performed to manage the overall requirements. This study has been developed according to the factual information and theories are intended to present the study in a proper manner

Gender and career advancement in the sciences: a Thai case study

This thesis is aimed to exploring a gender difference in scientific careers by presenting empirical evidence from Thailand, and also at evaluating the impact of different types of organisation: higher education and research institute sectors on gender and academic career progress. In order to understand gender dimensions in Thai academic careers, a multilevel analysis (Layder, 1993) is employed as a guide. With the pragmatic paradigm, the strength of this research has drawn both quantitative and qualitative approaches. In comparison to the developed world, Thailand, a country with relatively low competency in science has progressive numeric indices of the status of women in science. However, the findings of this study highlight the existence of a gender gap in rewards. Particularly, female academics in Thai higher education were found worse than their counterparts in the research institute sector as a result of certain organisational characteristics. This study reveals that Thai women in science remain under threat at different levels: constraints of the national scientific policy which focuses on engineering; Thai scientific organisational norms in favour of men; women’s limitations in social connections; and gendered roles which compel women to put family before career. On top of that, though Thai women perceive gender inequality in academic careers, they tend to disregard it. In order to eliminate gender disparities, Thai female academics need to raise their professional status through a range of activities: achieving privileged academic qualifications; joining each other through formal networks; adopting a male working style; deploying a conflict avoidance strategy; relying on rules and regulations; being single; and drawing on support from family and colleagues. However, it is noteworthy that some of these strategies seem to hinder women’ssuccess in science as well. Overall, the findings support the argument that although Thai female academics may try to devise strategies to survive in their careers, the success of such attempts often depends on structural norms which generate opportunities for them

Excitation Theory for Space-Dispersive Active Media Waveguides

A unified electrodynamic approach to the guided-wave excitation theory is generalized to the waveguiding structures containing a hypothetical space-dispersive medium with drifting charge carriers possessing simultaneously elastic, piezoelectric and magnetic properties. Substantial features of our electrodynamic approach are: (i) the allowance for medium losses and (ii) the separation of potential fields peculiar to the slow quasi-static waves. It is shown that the orthogonal complementary fields appearing inside the external source region are just associated with a contribution of the potential fields inherent in exciting sources. Taking account of medium losses converts the usual orthogonality relation into a novel form called the quasi-orthogonality relation. It is found that the separation of potential fields reveals the fine structure of interaction between the exciting sources and mode eigenfields: in addition to the exciting currents interacting with the curl fields, the exciting charges and the double charge (surface dipole) layers appear to interact with the quasi-static potentials and the displacement currents, respectively.Comment: LaTeX 2.09, 28 pages with mathematical appendi