Backup Strategy Research Articles

Multi-strategy ensemble biogeography-based optimization for economic dispatch problems

Economic dispatch (ED) is an important task in power system operation. It is able to decrease the operating cost, save energy resources, and reduce environmental load. In this paper, a multi-strategy ensemble biogeography-based optimization (MsEBBO) based method for ED problems is proposed. BBO is a population-based meta-heuristic algorithm inspired by the science of biogeography and mainly consists of three components: migration model, migration operator, and mutation operator. It has good local exploitation ability but lacks satisfactory global exploration ability. To keep a proper balance between exploration and exploitation, MsEBBO has three extensions to BBO’s three components according to the no free lunch theorem. First, a nonlinear migration model based on sinusoidal curve is employed. Second, a backup migration operator through adopting a backup strategy to combine perturb operator and blended operator is presented. This operator can make the entire population fully exchange or share information and thus further strengthen the exploitation ability. Finally, both differential mutation and Lévy local search are embedded as mutation operator for MsEBBO using a similar backup strategy. Gaining from this mutation operator, MsEBBO can be accelerated to escape from local optima and perform efficient search within global range. Additionally, an effective repair technique is proposed to handle different constraints of ED problems. The performance of MsEBBO is tested on four ED problems with diverse complexities. Experimental results and comparisons with other recently reported ED solution methods confirm that MsEBBO is capable of yielding a good balance between exploration and exploitation, and obtaining competitive solution quality. Moreover, the sensitivity of MsEBBO to variations in population size is investigated as well.

Design and Evaluation of a Provenance-Based Rebuild Framework

Previous storage reliability solutions mainly include log files, snapshot, backup or ECC-based schemes. These technologies focus more on the whole disk or system reliability, but not single data object. However, it is not efficient to rebuild a file by recovering a whole system using the technologies above. In this paper, we propose to use provenance, the origin or history of objects, to rebuild damaged or lost files. Provenance-based rebuild can exactly reconstruct the right file lost or damaged by backtracking its generation process in the past. The evaluation results show that provenance-based rebuild performs significantly better than log-based technology with reasonable time and space overhead.

Stochastic Modeling of Database Backup Policy for a Computer System

As the computer system has developed much in this highly information-oriented society, database security has become a very important problem and its backup strategies need to be made more efficiently and safety. The image copy method has been used as the most simple and dependable recovery mechanism for media failure. However, this method spends high overhead costs for massive data transmission and much processing time in the normal operation of the database. To cover such weak points, incremental and full backup methods are adopted before updated trucks reach a predetermined level. Moreover, when the number of full backup files exceeded a predetermined level, we stop incremental and full backups and switch it to the image copy. This paper applies cumulative damage model to backup of files in a database system, by putting damage shock by update, failure shock by database failure and damage by dumped files, and considers the tradeoff among overhead costs of image copy and incremental, full backup methods, and discusses analytically an optimal policy for the image copy backup interval. Finally, numerical examples are given in the case of Poisson process and exponential distributions.

A Moment of Truth in Translating Proper Names in Naguib Mahfouz’ Trilogy from Arabic into English

This study tackles the translation of proper names in Naguib Mahfouz’s Trilogy from Arabic into English. A masterpiece of three volumes, namely, Palace Walk, Palace of Desire, and Sugar Street, was translated by Hutchins and Kenny (1990), Hutchins, Kenny and Kenny (1991), and Hutchins and Saman (1992), respectively. In the English translation of this trilogy, proper names were preserved in a process of transliterating, thus maintaining a foreignized sense of rendition. Such mere strategy constitutes an alternative among a spectrum of many others suggested in the domain of translating proper names, viz., creation, adaptation, addition, omission, among others. Nevertheless, the researcher used four proper names as case studies representative of the inadequacy of merely transliterating proper names in Mahfouz’s literary work. Mahfouz imbued his work with an enchanting style that became an emblem of his folkloric locality. Yet this folkloric touch was not faithfully depicted in the English translation mainly due to the linguistic and cultural gaps between the source language and the target one. The analysis of the four names that the researcher purposefully chose represents such loss. A charge of functional equivalence and intended irony was traced thereby. Correspondingly, a backup strategy to compensate this inequivalence between the original work and its English rendition proves to be missing in doing justice to such work. Key words: Naguib Mahfouz; Literary translation; Foreignization; Domestication; Transliteration

Key Technologies and Application of Automatic Control System for Wide Stainless Steel Hot Strip Rolling Line

Wide stainless steel hot strip line integrated with mechanical electric hydraulic equipments is a complicated large system. Automatic control system is very important for improving mill efficiency and products quality. The new equipments and technology are introduced. The characteristics of hot strip line and its requests for automation, the ideas of control system design, system structure and configuration are explained in detail. Multilevel system, 1000M high speed fabric Ethernet between levels, 640M high speed global data memory network between controllers, high speed Profibus_DP network between controller and equipments, hot machine backup strategy of L2,Tri-cyclic fabric Ethernet redundancy of L1 and other innovative design ideas,and L2 main mathematic models, L1 key control models are all applied in the system. The design ideas of this paper and integrated automatic control system has been applied on several stainless steel hot strip lines.

Microsecond accuracy at multiple sites: is it possible without GPS?

Critical infrastructure timing systems rely upon GPS clocks simply because microsecond accuracy is easy to achieve with GPS and difficult to achieve without it. This paper has discussed how GPS clocks meet critical infrastructure timing requirements, why they are vulnerable, and some potential backup strategies. It seems clear that achieving microsecond accuracy at thousands of geographically dispersed sites without relying on GPS clocks is a very challenging problem. It seems equally clear that solving this problem is in the best interest of the United States.

Dependability Analysis of Control Center Networks in Smart Grid Using Stochastic Petri Nets

As an indispensable infrastructure for the future life, smart grid is being implemented to save energy, reduce costs, and increase reliability. In smart grid, control center networks have attracted a great deal of attention, because their security and dependability issues are critical to the entire smart grid. Several studies have been conducted in the field of smart grid security, but few work focuses on the dependability analysis of control center networks. In this paper, we adopt a concise mathematic tool, stochastic Petri nets (SPNs), to analyze the dependability of control center networks in smart grid. We present the general model of control center networks by considering different backup strategies of critical components. With the general SPNs model, we can measure the dependability from two metrics, i.e., the reliability and availability, through analyzing the transient and steady-state probabilities simultaneously. To avoid the state-space explosion problem in computing, the state-space explosion avoidance method is proposed as well. Finally, we study a specific case to demonstrate the feasibility and efficiency of the proposed model in the dependability analysis of control center networks in smart grid.

Intelli-restore as an instantaneous approach for reduced data recovery time

Due to the competitive and regulatory pressures and the high demands and dependence placed on data, there is need for higher data availability and a faster means of recovering the data in case it becomes corrupted or lost. Based on results provided on the reasons behind the long / high data recovery times by Kenyan SMEs this paper provides a solution that reduces the data recovery time. In order to solve the problem of high data recovery times, an instantaneous data recovery strategy based on an existing Continuous Data Protection (CDP) architecture is introduced as an important component of a well-rounded backup and recovery strategy. CDP is a disk based backup solution which ensures that data is retrieved at a much faster rate during recovery. The solution presented in this paper could help organizations adopt or complement existing data recovery strategies.

The Use of the Operand-Recognition Paradigm for the Study of Mental Addition in Older Adults

Determining how individuals solve arithmetic problems is crucial for our understanding of human cognitive architecture. Elderly adults are supposed to use memory retrieval more often than younger ones. However, they might backup their retrieval by reconstructive strategies. In order to investigate this issue, we used the operand-recognition paradigm, which capitalizes on the fact that algorithmic procedures degrade the memory traces of the operands. Twenty-three older adults (M = 70.4) and 23 younger adults (M = 20.0) solved easy, difficult, and medium-difficulty addition and comparison problems and were then presented with a recognition task of the operands. When one-digit numbers with sums larger than 10 were involved (medium-difficulty problem), it was more difficult for younger adults to recognize the operands after addition than comparison. In contrast, in older adults, recognition times of the operands were the same after addition and comparison. Older adults, in contrast with younger adults, are able to retrieve the results of addition problems of medium difficulty. Contrary to what was suggested, older participants do not seem to resort to backup strategies for such problems. Finally, older adults' reliance on the more efficient retrieval strategy allowed them to catch up to younger adults in terms of solution times.

Temperature- and Touch-Sensitive Neurons Couple CNG and TRPV Channel Activities to Control Heat Avoidance in Caenorhabditis elegans

BackgroundAny organism depends on its ability to sense temperature and avoid noxious heat. The nematode Caenorhabditis elegans responds to noxious temperatures exceeding ∼35°C and also senses changes in its environmental temperature in the range between 15 and 25°C. The neural circuits and molecular mechanisms involved in thermotaxis have been successfully studied, whereas details of the thermal avoidance behavior remain elusive. In this work, we investigate neurological and molecular aspects of thermonociception using genetic, cell biological and physiological approaches.Methodology/Principal FindingsWe show here that the thermosensory neurons AFD, in addition to sensing temperature within the range within which the animals can thrive, also contribute to the sensation of noxious temperatures resulting in a reflex-like escape reaction. Distinct sets of interneurons are involved in transmitting thermonociception and thermotaxis, respectively. Loss of AFD is partially compensated by the activity of a pair of multidendritic, polymodal neurons, FLP, whereas laser ablation of both types of neurons abrogated the heat response in the head of the animals almost completely. A third pair of heat sensory neurons, PHC, is situated in the tail. We find that the thermal avoidance response requires the cell autonomous function of cGMP dependent Cyclic Nucleotide-Gated (CNG) channels in AFD, and the heat- and capsaicin-sensitive Transient Receptor Potential Vanilloid (TRPV) channels in the FLP and PHC sensory neurons.Conclusions/SignificanceOur results identify distinct thermal responses mediated by a single neuron, but also show that parallel nociceptor circuits and molecules may be used as back-up strategies to guarantee fast and efficient responses to potentially detrimental stimuli.

How to automatically test and validate your database backup and recovery strategy

The major challenge we solve with this software project is the automated validation of backups sent to tape for Oracle databases. While Oracle Recovery Manager (RMAN) provides tools like 'restore validate', the real and only certain proof is a restore. This initial aim evolved to provide a recovery platform capable to cover more complex user cases, such as validations of backup strategy of Very Large DataBases (VLDB), and schema recoveries to cure logical errors or to provide the kind of database snapshots by means of exports.

Entry Dispersion Analysis for the HAYABUSA Spacecraft using Ground-Based Optical Observation

The HAYABUSA asteroid explorer successfully released its sample capsule to Australia on 2010 June 13. Since the Earth reentry phase of sample return was critical, many backup plans for predicting the landing location were prepared. This paper considers the reentry dispersion using ground-based optical observation as a backup observation for radiometric observation. Several scenarios were calculated and compared for the reentry phase of HAYABUSA to evaluate the navigation accuracy of the ground-based observation. The optical observation doesn't require any active reaction from a spacecraft, and thus these results show that optical observations could be a steady backup strategy even if a spacecraft had some trouble. We also evaluated the landing dispersion of HAYABUSA only with optical observation.

Strategy to fight clopidogrel resistance: a multiplex genetic variants investigation in Chinese population

ObjectiveClopidogrel is widely used to treat ischemic heart disease and unexpected resistance could result in severe clinical incidents. Genetic variation has been suggested as the most important factor in intrinsic...

Service-level assurance in high-availability multi-unit systems using the M-for-N backup scheme

In this paper, we investigate service-level assurance in high-availability multi-unit systems using the M-for-N backup scheme. M-for-N shared protection (backup) systems with priority control (i.e. prioritized protection switching and prioritized re-housing of repaired units) can be applied to actual telecommunication devices that are subject to service-level agreement (SLA) involving reliability measures. A priority level is assigned to each end user in such a system and the switching and unit re-housing process is subject to the priority. The main contribution of this paper is to give a practical computation method of the user-perceived availability under the priority control. Our case studies for real telecommunication systems reveal the effect of priority control on the user-perceived availability. Copyright © 2011 John Wiley & Sons, Ltd.

Continuous Data Protection as a Strategy for Reduced Data Recovery Time

This paper presents the reasons behind the long / high data recovery times by Kenyan Firms and provides a solution that reduces the data backup for recovery time. It was found that the time taken to recover data was reasonably high because of the type of media that was used for backing up data: the magnetic data tape. In order to solve the problem of high data recovery times, Continuous Data Protection (CDP) is introduced as an important component of a well-rounded backup and recovery strategy to complement the existing backup strategy as CDP is a disk based backup solution which ensures that data is retrieved at a much faster rate. The findings presented in this paper could help researchers design a strategy for instanteneous data recovery based on Continuous Data protection.

Finger usage and arithmetic in adults with math difficulties: evidence from a case report

The role of finger usage upon learning arith-metic has received increasing interest from various disciplines. In this opinion paper, we would like to emphasize that finger usage in calculation is not a unitary phenomenon. Rather, we propose two different types of finger usage: First, in many countries and independent of the number system in use, typically developing children use fingers as important transitory (and intuitive) tools to represent small quantities ( Butterworth, 1999; Bender and Beller, 2011). According to Di Luca and Pesenti (2011) , finger count-ing habits are needed to build, acquire, and access mental number representations, the building blocks for semantic number knowledge. Second, developmentally inap-propriate finger usage of children with math difficulties (MD) reflects their persistent need to apply back-up strategies to compen-sate for deficient or lacking number repre-sentations (e.g., Brissaud, 1992; Kaufmann, 2002; Wright et al., 2002). Here, we will focus on the second type of finger usage (i.e., persistent finger usage in individuals with MD) and we argue that (a) finger usage in arithmetic is not restricted to children; and (b) finger-based calculation strategies utilized by adults with MD reflect immature calculation strategies that are comparable to those displayed by affected children.

What’s your back-up strategy?

What’s your back-up strategy?

Making the case for plant diversity

AbstractThe Millennium Ecosystem Assessment estimates that between 60,000 and 100,000 plant species are threatened with extinction–equivalent to around one-quarter of the total number of known plant species. Why should we care? There are a number of reasons. The first is that these plants may be useful to us in unknown ways. Secondly, ecology has taught us that resilience is found in diversity. Thirdly, we should be saving plant species from extinction because we can–there is no technological reason why any plant species should become extinct. Where we can't protect and manage plant diversity in situ, we should be employing ex situ conservation techniques, ranging from seed banks to habitat restoration. The Millennium Ecosystem Assessment describes such interventions as ‘techno-gardening’. This is not an abstract concept–it is already a reality in the majority of man-managed landscapes. In this context the perception of ex situ conservation as simply a back-up strategy for in situ conservation is mistaken. We are all involved in ex situ conservation to some degree, from cultivating our back gardens, to farming, to management of protected areas. Ex situ conservation should be seen as a complementary approach to in situ conservation and on the same spectrum. Kew's Millennium Seed Bank Partnership, comprising more than 120 plant science institutions in 50 countries, epitomizes this philosophy in action. We work actively on every seed collection we bank, finding out how useful it is and how we can grow it to enable human innovation, adaptation and resilience. Challenges remain at the policy level; for example, the need to factor-in the value of natural capital to development decision making, and better defining a role for public-sector science. At the technical level, also, there is much to do. Perhaps the greatest technical challenges relate to the restoration and management of complex, self-sustaining habitats or species assemblages. If we are to techno-garden effectively, in order to maintain ecosystem services and sustain biodiversity, then a multidisciplinary approach will be required. Many plant science institutions have recognized this and are becoming engaged increasingly in restoration activities and in situ management. Ultimately, humanity's ability to innovate and adapt is dependent on our having access to the full range of plant species and the alleles they contain.

Discovery Tactics To Mitigate Toxicity Risks Due to Reactive Metabolite Formation with 2-(2-Hydroxyaryl)-5-(trifluoromethyl)pyrido[4,3-d]pyrimidin-4(3H)-one Derivatives, Potent Calcium-Sensing Receptor Antagonists and Clinical Candidate(s) for the Treatment of Osteoporosis

The synthesis and structure-activity relationship studies on 5-trifluoromethylpyrido[4,3-d]pyrimidin-4(3H)-ones as antagonists of the human calcium receptor (CaSR) have been recently disclosed [ Didiuk et al. ( 2009 ) Bioorg. Med. Chem. Lett. 19 , 4555 - 4559 ). On the basis of its pharmacology and disposition attributes, (R)-2-(2-hydroxyphenyl)-3-(1-phenylpropan-2-yl)-5-(trifluoromethyl)pyrido[4,3-d]pyrimidin-4(3H)-one (1) was considered for rapid advancement to first-in-human (FIH) trials to mitigate uncertainty surrounding the pharmacokinetic/pharmacodynamic (PK/PD) predictions for a short-acting bone anabolic agent. During the course of metabolic profiling, however, glutathione (GSH) conjugates of 1 were detected in human liver microsomes in an NADPH-dependent fashion. Characterization of the GSH conjugate structures allowed insight(s) into the bioactivation pathway, which involved CYP3A4-mediated phenol ring oxidation to the catechol, followed by further oxidation to the electrophilic ortho-quinone species. While the reactive metabolite (RM) liability raised concerns around the likelihood of a potential toxicological outcome, a more immediate program goal was establishing confidence in human PK predictions in the FIH study. Furthermore, the availability of a clinical biomarker (serum parathyroid hormone) meant that PD could be assessed side by side with PK, an ideal scenario for a relatively unprecedented pharmacologic target. Consequently, progressing 1 into the clinic was given a high priority, provided the compound demonstrated an adequate safety profile to support FIH studies. Despite forming identical RMs in rat liver microsomes, no clinical or histopathological signs prototypical of target organ toxicity were observed with 1 in in vivo safety assessments in rats. Compound 1 was also devoid of metabolism-based mutagenicity in in vitro (e.g., Salmonella Ames) and in vivo assessments (micronuclei induction in bone marrow) in rats. Likewise, metabolism-based studies (e.g., evaluation of detoxicating routes of clearance and exhaustive PK/PD studies in animals to prospectively predict the likelihood of a low human efficacious dose) were also conducted, which mitigated the risks of idiosyncratic toxicity to a large degree. In parallel, medicinal chemistry efforts were initiated to identify additional compounds with a complementary range of human PK predictions, which would maximize the likelihood of achieving the desired PD effect in the clinic. The back-up strategy also incorporated an overarching goal of reducing/eliminating reactive metabolite formation observed with 1. Herein, the collective findings from our discovery efforts in the CaSR program, which include the incorporation of appropriate derisking steps when dealing with RM issues are summarized.

Current aspects and future trends of computer-aided rescaffolding

The competitive pressure in pharmaceutical industry is reflected by longer development times and increasing development costs yielding less new chemical entities. In particular, identification of suitable lead compounds is one of the key challenges in early drug discovery. Next to well established techniques like high throughput screening (HTS) and virtual screening computer-aided rescaffolding has become an important approach in detecting novel chemical structures [1,2]. The development of New Chemical Entities (NCEs) requires the exploration of novel landscapes in chemical space. Rescaffolding is in particular important in lead identification but also in lead optimization. If a lead series cannot be optimized in multidimensional space, scaffold-rescuing is often perceived as back-up strategy to transfer hitherto available SAR into a new scaffold. With a binding site or a pharmacophore in hand often de novo design methods are applied to identify novel chemical matter. However, de novo design differs from rescaffolding in that the goal of the first is primarily to generate new molecules in chemical space while the latter aims to design new scaffolds under constraints: high similarity in the desired property space and novelty in scaffold space. This allows jumping out of the known region of chemical space towards new regions of chemistry resulting in molecules with similar properties and activities but with novel frameworks. This talk will focus on ligand-based rescaffolding by taking into account only the topology of reference molecules. Several descriptors have been successfully applied for rescaffolding purposes, e.g. CATS (including CATS3D), Feature Trees (cf. ReCore), Topomers, Gaussian shape (cf. ROCS, BROOD) and others. In fragment-based rescaffolding new molecules are assembled from small (sub-) molecular fragments or building blocks often by applying pseudo-chemical rules in their recombination (e.g., RECAP). The use of fragments reduces the sampling rate of chemical space and provides access to synthesizable new compounds. This will be exemplified by two rescaffolding examples taking into account 2D as well as 3D descriptors.