Search results for " windows"
showing 10 items of 51 documents
A penalty-based edge assembly memetic algorithm for the vehicle routing problem with time windows
2010
In this paper, we present an effective memetic algorithm for the vehicle routing problem with time windows (VRPTW). The paper builds upon an existing edge assembly crossover (EAX) developed for the capacitated VRP. The adjustments of the EAX operator and the introduction of a novel penalty function to eliminate violations of the time window constraint as well as the capacity constraint from offspring solutions generated by the EAX operator have proven essential to the heuristic's performance. Experimental results on Solomon's and Gehring and Homberger benchmarks demonstrate that our algorithm outperforms previous approaches and is able to improve 184 best-known solutions out of 356 instance…
Pieejas “Windows kā pakalpojums” izmantošana atjauninājumu instalēšanas automatizācijai organizācijas Windows operētājsistēmās
2020
Katru mēnesi tiek veikti operētājsistēmu uzlabojumi un izlaisti atjauninājumi. Tāpēc ir ļoti svarīgi nodrošināt, lai tehniskās ierīces būtu atjaunotas un tās saņemtu jaunākos drošības un funkcionalitātes labojumus, kas mazinātu operētājsistēmas darbības traucējumu rašanās risku. Darba mērķis ir veikt atjauninājumu instalēšanas automatizāciju organizācijas Windows operētājsistēmās izmantojot pieeju “Windows kā pakalpojums”. Darbā tika veikts vispārīgs pieejas “Windows kā pakalpojums” metožu apraksts un pielietotas pieejas metodes atjauninājumu automatizācijai, tādas kā Windows Server Update Services (WSUS) un Microsoft Endpoint Configuration Manager (MECM). Darba rezultātā ir veikta Windows …
Risk-Managed Industry Momentum and Momentum Crashes
2016
This is the first paper that investigates Barosso and Santa-Clara’s (2015) risk-managed momentum strategy in an industry momentum setting. We investigate traditional momentum strategies and Novy-Marx (2012) strategy. We also explore the impact of different variance forecast horizons on the average payoffs. We find that risk-managed industry momentum payoffs generate considerably higher returns than plain momentum strategies. Notably, risk-managed payoffs increase linearly as the time window for variance forecasts are contracted which is consistent for all different strategies.
225 Comparative analysis of patients with acute coronary and cerebrovascular syndromes from the national French hospitalisation heath care system dat…
2011
ObjectiveTo compare vascular risk factor profiles and early outcomes in all French patients hospitalized for either acute coronary (ACS), or cerebrovascular syndromes (CVS), or both, between 2005 and 2008.SettingAll French hospitals.DesignRetrospective analysis.Data sourcesNational database called “Hospital Discharge Diagnosis Records”.Main outcomes measuredNumber and annual rates, vascular risk factors, and early outcome of hospitalized patients for a unique stay for ACS or CVS or for both ACV and CVS in a 2-month time window.ResultsOver the 4-year study-period, 1,189,043 patients were hospitalized for CVS and/or ACS. Among these, 638,061 (53.7%) had CVS alone, 525,419 (44.3%) had ACS alon…
Bank-firm credit network in Japan. An analysis of a bipartite network
2015
We present an analysis of the credit market of Japan. The analysis is performed by investigating the bipartite network of banks and firms which is obtained by setting a link between a bank and a firm when a credit relationship is present in a given time window. In our investigation we focus on a community detection algorithm which is identifying communities composed by both banks and firms. We show that the clusters obtained by directly working on the bipartite network carry information about the networked nature of the Japanese credit market. Our analysis is performed for each calendar year during the time period from 1980 to 2011. Specifically, we obtain communities of banks and networks …
Branch-and-Cut-and-Price for the Vehicle Routing Problem with Time Windows and Convex Node Costs
2019
Two critical yet frequently conflicting objectives for logistics and transportation service companies are improving customer satisfaction and reducing transportation cost. In particular, given a network of customer requests with preferred service times, it is very challenging to find vehicle routes and service schedules simultaneously that respect all operating constraints and minimize the total transportation and customers’ inconvenience costs. In this paper, we introduce the vehicle routing problem with time windows and convex node costs (VRPTW-CNC), in which we model each customer’s inconvenience cost as a convex function of the service start time at that customer. The VRPTW-CNC combine…
Thermochromic Thin Films: Synthesis, Properties and Energy Consumption Modelling
2013
Thermochromic materials such as vanadium dioxide have been postulated for use in “SMART” windows for a number of years. Such windows work by exploiting a structural phase change from an infra-red transmissive state to a infra-red reflective state. Significant challenges still remain before such materials will be able to find wide spread use. In this mini review we discuss the nature of this thermochromic transition with reference to the latest research work in the field. We pay particular attention to challenges such as film colouration, transition temperature, and transition hysteresis. We describe the most up to date strategies for addressing these challenges, considering advanced synthes…
Degree stability of a minimum spanning tree of price return and volatility
2002
We investigate the time series of the degree of minimum spanning trees obtained by using a correlation based clustering procedure which is starting from (i) asset return and (ii) volatility time series. The minimum spanning tree is obtained at different times by computing correlation among time series over a time window of fixed length $T$. We find that the minimum spanning tree of asset return is characterized by stock degree values, which are more stable in time than the ones obtained by analyzing a minimum spanning tree computed starting from volatility time series. Our analysis also shows that the degree of stocks has a very slow dynamics with a time-scale of several years in both cases.
Quaternary structure dependence of kinetic hole burning and conformational substates interconversion in hemoglobin.
2003
Using a sol-gel encapsulation technique, we have prepared samples of CO saturated human adult hemoglobin locked in the R or T quaternary conformation. We report time-resolved spectra of these samples in the Soret region following flash photolysis, in the time interval ranging from 250 ns to 200 ms and in the temperature interval of 100-170 K. A suitable analysis of the measured difference spectra enables us to obtain the spectral contribution of deoxyHb and HbCO molecules as a function of time and/or of the fraction N(t) of deoxyHb molecules. In our experimental time window geminate CO rebinding to hemoglobin in the T quaternary conformation is about 2 orders of magnitude slower than to hem…
A simple timestamping data acquisition system for ToF-ERDA
2015
A new data acquisition system, ToF-DAQ, has been developed for a ToF-ERDA telescope and other ToF-E and ToF-ToF measurement systems. ToF-DAQ combines an analogue electronics front-end to asynchronous time stamped data acquisition by means of a FPGA device. Coincidences are sought solely in software based on the timestamps. Timestamping offers more options for data analysis as coincidence events can be built also in offline analysis. The system utilises a National Instruments R-series FPGA device and a Windows PC as a host computer. Both the FPGA code and the host software were developed using the National Instruments LabVIEW graphical programming environment. Up to eight NIM ADCs can be han…