Operating System Contribution to Composable Timing Behaviour in High-Integrity Real-Time Systems

The development of High-Integrity Real-Time Systems has a high footprint in terms of human, material and schedule costs. Factoring functional, reusable logic in the application favors incremental development and contains costs. Yet, achieving incrementality in the timing behavior is a much harder problem. Complex features at all levels of the execution stack, aimed to boost average-case performance, exhibit timing behavior highly dependent on execution history, which wrecks time composability and incrementaility with it. Our goal here is to restitute time composability to the execution stack, working bottom up across it. We first characterize time composability without making assumptions on the system architecture or the software deployment to it. Later, we focus on the role played by the real-time operating system in our pursuit. Initially we consider single-core processors and, becoming less permissive on the admissible hardware features, we devise solutions that restore a convincing degree of time composability. To show what can be done for real, we developed TiCOS, an ARINC-compliant kernel, and re-designed ORK+, a kernel for Ada Ravenscar runtimes. In that work, we added support for limited-preemption to ORK+, an absolute premiere in the landscape of real-word kernels. Our implementation allows resource sharing to co-exist with limited-preemptive scheduling, which extends state of the art. We then turn our attention to multicore architectures, first considering partitioned systems, for which we achieve results close to those obtained for single-core processors. Subsequently, we shy away from the over-provision of those systems and consider less restrictive uses of homogeneous multiprocessors, where the scheduling algorithm is key to high schedulable utilization. To that end we single out RUN, a promising baseline, and extend it to SPRINT, which supports sporadic task sets, hence matches real-world industrial needs better. To corroborate our results we present findings from real-world case studies from avionic industry.

Immigrants in the Czech Republic (With Special Reference to Ukrainian Workers and "Western" Firms Operating in Prague)

International migration has increased rapidly in the Czech Republic, with more than 150,000 legally registered foreign residents at the end of 1996. A large proportion of these are in Prague - 35% of the total in December 1996. The aim of this project was to enrich the fund of information concerning the "environment", reasons and "mechanisms" behind immigration to the Czech Republic. Mr. Drbohlav looked first at the empirical situation and on this basis set out to test certain well-known migration theories. He focused on four main areas: 1) a detailed description and explanation of the stock of foreign citizens legally settled in Czech territory, concentrating particularly on "economic" migrants; 2) a questionnaire survey targeting a total of 192 Ukrainian workers (98 in the fall 1995 and 94 in the fall 1996) working in Prague or its vicinity; 3) a second questionnaire survey of 40 "western" firms (20 in 1996 and 20 in 1997) operating out of Prague; 4) an opinion poll on how the Czech population reacts to foreign workers in the CR. Over 80% of economic immigrants at the end of 1996 were from European countries, 16% from Asia and under 2% from North America. The largest single nationalities were Ukrainians, Slovaks, Vietnamese and Poles. There has been a huge increase in the Ukrainian immigrant community over both space (by region) and time (a ten-fold increase since 1993), and at 40,000 persons this represents one third of all legal immigrants. Indications are that many more live and work there illegally. Young males with low educational/skills levels predominate, in contrast with the more heterogeneous immigration from the "West". The primary reason for this migration is the higher wages in the Czech Republic. In 1994 the relative figures of GDP adjusted for parity of purchasing power were US$ 8,095 for the Czech Republic versus US$ 3,330 for the Ukraine as a whole and US$ 1,600 for the Zakarpatye region from which 49% of the respondents in the survey came. On an individual level, the average Czech wage is about US$ 330 per month, while 50% of the Ukrainian respondents put their last monthly wage before leaving for the Czech Republic at under US$ 27. The very low level of unemployment in the latter country (fluctuating around 4%) was also mentioned as an important factor. Migration was seen as a way of diversifying the family's source of income and 49% of the respondents had made their plans together with partners or close relatives, while 45% regularly send remittances to Ukraine (94% do so through friends or relatives). Looking at Ukrainian migration from the point of view of the dual market theory, these migrants' type and conditions of work, work load and earnings were all significantly worse than in the primary sector, which employs well educated people and offers them good earnings, job security and benefits. 53% of respondents were working and/or staying in the Czech Republic illegally at the time of the research, 73% worked as unqualified, unskilled workers or auxiliary workers, 62% worked more than 12 hours a day, and 40% evaluated their working conditions as hard. 51% had no days off, earnings were low in relation to the number of hours worked. and 85% said that their earnings did not increase over time. Nearly half the workers were recruited in Ukraine and only 4% expressed a desire to stay in the Czech Republic. Network theories were also borne out to some extent as 33% of immigrants came together with friends from the same village, town or region in Ukraine. The number who have relatives working in the Czech Republic is rising, and many wish to invite relatives or children to visit them. The presence of organisations which organised cross-border migration, including some which resort to organising illegal documents, also gives some support for the institutional theory. Mr. Drbohlav found that all the migration theories considered offered some insights on the situation, but that none was sufficient to explain it all. He also points out parallels with many other regions of the world, including Central America, South and North America, Melanesia, Indonesia, East Africa, India, the Middle East and Russia. For the survey of foreign and international firms, those chosen were largely from countries represented by more than one company and were mainly active in market services such as financial and trade services, marketing and consulting. While 48% of the firms had more than 10,000 employees spread through many countries, more than two thirds had fewer than 50 employees in the Czech Republic. Czechs formed 80% plus of general staff in these firms although not more than 50% of senior management, and very few other "easterners" were employed. All companies absolutely denied employing people illegally. The average monthly wage of Czech staff was US$ 850, with that of top managers from the firm's "mother country" being US$ 6,350 and that of other western managers US$ 3,410. The foreign staff were generally highly mobile and were rarely accompanied by their families. Most saw their time in the Czech Republic as positive for their careers but very few had any intention of remaining there. Factors in the local situation which were evaluated positively included market opportunities, the economic and political environment, the quality of technical and managerial staff, and cheap labour and low production costs. In contrast, the level of appropriate business ethics and conduct, the attitude of local and regional authorities, environmental production conditions, the legal environment and financial markets and fiscal policy were rated very low. In the final section of his work Mr. Drbohlav looked at the opinions expressed by the local Czech population in a poll carried out at the beginning of 1997. This confirmed that international labour migration has become visible in this country, with 43% of respondents knowing at least one foreigner employed by a Czech firm in this country. Perception differ according to the region from which the workers come and those from "the West" are preferred to those coming from further east. 49% saw their attitude towards the former as friendly but only 20% felt thus towards the latter. Overall, attitudes towards migrant workers is neutral, although 38% said that such workers should not have the same rights as Czech citizens. Sympathy towards foreign workers tends to increase with education and the standard of living, and the relatively positive attitudes towards foreigners in the South Bohemia region contradicted the frequent belief that a lack of experience of international migration lowers positive perceptions of it.

The value of cultural assets. Maintenance Costs and economic sustainability at heritage

Under the 12th International Conference on Building Materials and Components is inserted this communication related to the field of management of those assets that constitute the Spanish Cultural Heritage and maintenance. This work is related to the field of management of those assets that constitute the Spanish Cultural Heritage which share an artistic or historical background. The conservation and maintenance become a social demand necessary for the preservation of public values, requiring the investment of necessary resources. The legal protection involves a number of obligations and rights to ensure the conservation and heritage protection. The duty of maintenance and upkeep exceeds the useful life the property that must endure more for their cultural value for its usability. The establishment of the necessary conditions to prevent deterioration and precise in order to fulfill its social function, seeking to prolong the life of the asset, preserving their physical integrity and its ability to convey the values protected. This obligation implies a substantial financial effort to the holder of the property, either public or private entity, addressing a problem of economic sustainability. Economic exploitation, with the aim of contributing to their well-maintained, is sometimes the best way to get resources. The work will include different lines of research with the following objectives. - Establishment of processes for assessing total costs over the building life cycle (LCC), during the planning stages or maintenance budgets to determine the most advantageous operating system. - Relationship between the value of property and maintenance costs, and establishing a sensitivity analysis.

Emissions and economic costs of cycling compact fluorescent lamps with integrated ballasts

This paper proposes a way to quantify the emissions of mercury (Hg) and CO2 associated with the manufacture and operation of compact fluorescent lamps with integrated ballasts (CFLis), as well as the economic cost of using them under different operating cycles. The main purpose of this paper is to find simple criteria for reducing the polluting emissions under consideration and the economic cost of CFLi to a minimum. A lifetime model is proposed that allows the emissions and costs to be described as a function of degradation from turning CFLi on and their continuous operation. An idealized model of a CFLi is defined that combines characteristics stated by different manufacturers. In addition, two CFLi models representing poor-quality products are analyzed. It was found that the emissions and costs per unit of time of operation of the CFLi depend linearly on the number of times per unit of time it is turned on and the time of continuous operation. The optimal conditions (lowest emissions and costs) depend on the place of manufacture, the place of operation and the quality of the components of the lamp/ballast. Finally, it was also found that for each lamp, there are intervals when it is turned off during which emissions of pollutants and costs are identical regardless of how often the lamp is turned on or the time it remains on. For CO2 emissions, the lamp must be off up to 5 minutes; for the cost, up to 7 minutes and for Hg emissions, up to 43 minutes. It is advisable not to turn on a CFLi sooner than 43 minutes from the last time it was turned off.

Analysis of the operating efficiency of mobile operators during the 2002 to 2008 period

This article aims to quantify the efficiency of mobile operators in Spain and other European countries such as France and Germany. The period considered is from 2002 to 2008. Linear regression is used to analyze the relationship between growth in revenue and gross operating margin (EBITDA) generated by the relevant operators and the aggregate industry in each country. At the industry level, it is shown that (i) there is a strong correlation between revenue and margin; and (ii) this correlation weakens when competitive intensity grows. At the operator level, those which achieved larger increases in revenues did not sacrifice their margins, but offset the additional investments and costs required to achieve said growth through economies of scale.

The Composition and Drivers of Energy Prices and Costs in Energy-Intensive Industries: The Case of Ceramics, Glass and Chemicals. CEPS Special Report No. 85, 27 March 2014

In May 2013, the European Commission received a mandate from the European Council to “to present an analysis of the composition and drivers of energy prices and costs in Member States, with a particular focus on the impact on households, SMEs and energy intensive industries, and looking more widely at the EU's competitiveness vis-à-vis its global economic counterparts”. Following such mandate and in view of the preparation by the Commission of a Communication and a Staff Working Document, DG Enterprise and Industry commissioned CEPS to carry out a set of studies aimed at providing well-grounded evidence about the evolution and composition of energy prices and costs at plant level within individual industry sectors. A team of CEPS researchers conducted the research, led by Christian Egenhofer and Lorna Schrefler. Vasileios Rizos served as Project Coordinator. Other CEPS researchers contributing to the project included: Fabio Genoese, Andrea Renda, Andrei Marcu, Julian Wieczorkiewicz, Susanna Roth, Federico Infelise, Giacomo Luchetta, Lorenzo Colantoni, Wijnand Stoefs, Jacopo Timini and Felice Simonelli. In addition to an introductory report entitled “About the Study and Cross-Sectoral Analysis”, CEPS prepared five sectoral case studies: two on ceramics (wall and floor tiles and bricks and roof tiles), two on chemicals (ammonia and chlorine) and one on flat glass. Each of these six studies has been consolidated in this single volume for free downloading on the CEPS website. The specific objective was to complement information already available at macro level with a bottom-up perspective on the operating conditions that industry stakeholders need to deal with, in terms of energy prices and costs. The approach chosen was based on case studies for a selected set (sub-)sectors amongst energy-intensive industries. A standard questionnaire was circulated and respondents were sampled according to specified criteria. Data and information collected were finally presented in a structured format in order to guarantee comparability of results between the different (sub-)sectors analysed. The complete set of files can also be downloaded from the European Commission’s website: http://ec.europa.eu/enterprise/newsroom/cf/itemdetail.cfm?item_id=7238&lang=en&title=Study-on-composition-and-drivers-of-energy-prices-and-costs-in-energy-intnsive-industries The results of the studies were presented at a CEPS Conference held on February 26th along with additional evidence from other similar studies. The presentations can be downloaded at: http://www.ceps.eu/event/level-and-drivers-eu-energy-prices-energy-inten...

The causes of rising transit operating deficits. Final report.

Urban Mass Transportation Administration, Washington, D.C.

Precision-recall operating characteristic (P-ROC) curves in imprecise environments

Traditionally, machine learning algorithms have been evaluated in applications where assumptions can be reliably made about class priors and/or misclassification costs. In this paper, we consider the case of imprecise environments, where little may be known about these factors and they may well vary significantly when the system is applied. Specifically, the use of precision-recall analysis is investigated and compared to the more well known performance measures such as error-rate and the receiver operating characteristic (ROC). We argue that while ROC analysis is invariant to variations in class priors, this invariance in fact hides an important factor of the evaluation in imprecise environments. Therefore, we develop a generalised precision-recall analysis methodology in which variation due to prior class probabilities is incorporated into a multi-way analysis of variance (ANOVA). The increased sensitivity and reliability of this approach is demonstrated in a remote sensing application.

Costs and efficiency of higher education institutions in England:a DEA analysis

As student numbers in higher education in the UK have expanded during recent years, it has become increasingly important to understand its cost structure. This study applies Data Envelopment Analysis (DEA) to higher education institutions in England to assess their cost structure, efficiency and productivity. The paper complements an earlier study that used parametric methods to analyse the same panel data. Interestingly, DEA provides estimates of subject-specific unit costs that are in the same ballpark as those provided by the parametric methods. The paper then extends the previous analysis and finds that further student number increases of the order of 20–27% are feasible through exploiting operating and scale efficiency gains and also adjusting student mix. Finally the paper uses a Malmquist index approach to assess productivity change in the UK higher education. The results reveal that for a majority of institutions productivity has actually decreased during the study period.

A simulation analysis of spoke-terminals operating in LTL Hub-and-Spoke freight distribution systems

DUE TO COPYRIGHT RESTRICTIONS ONLY AVAILABLE FOR CONSULTATION AT ASTON UNIVERSITY LIBRARY AND INFORMATION SERVICES WITH PRIOR ARRANGEMENT The research presented in this thesis is concerned with Discrete-Event Simulation (DES) modelling as a method to facilitate logistical policy development within the UK Less-than-Truckload (LTL) freight distribution sector which has been typified by “Pallet Networks” operating on a hub-and-spoke philosophy. Current literature relating to LTL hub-and-spoke and cross-dock freight distribution systems traditionally examines a variety of network and hub design configurations. Each is consistent with classical notions of creating process efficiency, improving productivity, reducing costs and generally creating economies of scale through notions of bulk optimisation. Whilst there is a growing abundance of papers discussing both the network design and hub operational components mentioned above, there is a shortcoming in the overall analysis when it comes to discussing the “spoke-terminal” of hub-and-spoke freight distribution systems and their capabilities for handling the diverse and discrete customer profiles of freight that multi-user LTL hub-and-spoke networks typically handle over the “last-mile” of the delivery, in particular, a mix of retail and non-retail customers. A simulation study is undertaken to investigate the impact on operational performance when the current combined spoke-terminal delivery tours are separated by ‘profile-type’ (i.e. retail or nonretail). The results indicate that a potential improvement in delivery performance can be made by separating retail and non-retail delivery runs at the spoke-terminal and that dedicated retail and non-retail delivery tours could be adopted in order to improve customer delivery requirements and adapt hub-deployed policies. The study also leverages key operator experiences to highlight the main practical implementation challenges when integrating the observed simulation results into the real-world. The study concludes that DES be harnessed as an enabling device to develop a ‘guide policy’. This policy needs to be flexible and should be applied in stages, taking into account the growing retail-exposure.

A simulation-based decision support system for evaluating operating policies in an emergency room facility

Increased pressure to control costs and increased competition has prompted health care managers to look for tools to effectively operate their institutions. This research sought a framework for the development of a Simulation-Based Decision Support System (SB-DSS) to evaluate operating policies. A prototype of this SB-DSS was developed. It incorporates a simulation model that uses real or simulated data. ER decisions have been categorized and, for each one, an implementation plan has been devised. Several issues of integrating heterogeneous tools have been addressed. The prototype revealed that simulation can truly be used in this environment in a timely fashion because the simulation model has been complemented with a series of decision-making routines. These routines use a hierarchical approach to organize the various scenarios under which the model may run and to partially reconfigure the ARENA model at run time. Hence, the SB-DSS tailors its responses to each node in the hierarchy.

COMPARATIVE ANALYSIS OF EFFICIENCY AND OPERATING CHARACTERISTICS OF AUTOMOTIVE POWERTRAIN ARCHITECTURES THROUGH CHASSIS DYNAMOMETER TESTING

The thesis "COMPARATIVE ANALYSIS OF EFFICIENCY AND OPERATING CHARACTERISTICS OF AUTOMOTIVE POWERTRAIN ARCHITECTURES THROUGH CHASSIS DYNAMOMETER TESTING" was completed through a collaborative partnership between Michigan Technological University and Argonne National Laboratory under a contractual agreement titled "Advanced Vehicle Characterization at Argonne National Laboratory". The goal of this project was to investigate, understand and document the performance and operational strategy of several modern passenger vehicles of various architectures. The vehicles were chosen to represent several popular engine and transmission architectures and were instrumented to allow for data collection to facilitate comparative analysis. In order to ensure repeatability and reliability during testing, each vehicle was tested over a series of identical drive cycles in a controlled environment utilizing a vehicle chassis dynamometer. Where possible, instrumentation was preserved between vehicles to ensure robust data collection. The efficiency and fuel economy performance of the vehicles was studied. In addition, the powertrain utilization strategies, significant energy loss sources, tailpipe emissions, combustion characteristics, and cold start behavior were also explored in detail. It was concluded that each vehicle realizes different strengths and suffers from different limitations in the course of their attempts to maximize efficiency and fuel economy. In addition, it was observed that each vehicle regardless of architecture exhibits significant energy losses and difficulties in cold start operation that can be further improved with advancing technology. It is clear that advanced engine technologies and driveline technologies are complimentary aspects of vehicle design that must be utilized together for best efficiency improvements. Finally, it was concluded that advanced technology vehicles do not come without associated cost; the complexity of the powertrains and lifecycle costs must be considered to understand the full impact of advanced vehicle technology.

Modelagem e gestão das perdas no suprimento de tomates para processamento industrial

O suprimento de tomates para processamento industrial é uma atividade relativamente complexa. Plantas industriais de larga escala necessitam de elevados volumes diários de matéria-prima. Por outro lado, há alta perecibilidade dos frutos e a colheita ainda é predominantemente manual. Um modelo matemático foi desenvolvido com o propósito de entender objetivamente o processo de suprimento de tomate e, também, vislumbrar possibilidades de sua otimização. A simulação a partir do modelo pode gerar cenários que, quando comparados com o desempenho efetivamente observado em campo, evidenciam a importância da gestão acurada, com a presença de potenciais ganhos financeiros expressivos na cadeia de suprimentos a partir da redução de tempos, perdas e custos. As perdas de produto poderiam ser reduzidas de mais de 2% para algo inferior a 1%. A menor capacidade ociosa traduzir-se-ia em um menor custo de oportunidade e aumento de receita. Para uma fábrica com um consumo de tomates de 336 mil toneladas por ano, a melhoria no suprimento de matéria-prima poderia resultar em ganhos estimados em R$ 6 milhões por ano.

Diffractive phase-shift lithography photomask operating in proximity printing mode

A phase shift proximity printing lithographic mask is designed, manufactured and tested. Its design is based on a Fresnel computer-generated hologram, employing the scalar diffraction theory. The obtained amplitude and phase distributions were mapped into discrete levels. In addition, a coding scheme using sub-cells structure was employed in order to increase the number of discrete levels, thus increasing the degree of freedom in the resulting mask. The mask is fabricated on a fused silica substrate and an amorphous hydrogenated carbon (a:C-H) thin film which act as amplitude modulation agent. The lithographic image is projected onto a resist coated silicon wafer, placed at a distance of 50 mu m behind the mask. The results show a improvement of the achieved resolution - linewidth as good as 1.5 mu m - what is impossible to obtain with traditional binary masks in proximity printing mode. Such achieved dimensions can be used in the fabrication of MEMS and MOEMS devices. These results are obtained with a UV laser but also with a small arc lamp light source exploring the partial coherence of this source. (C) 2010 Optical Society of America

Thermal lens and heat generation of Nd : YAG lasers operating at 1.064 and 1.34 mu m

We report on a simple and accurate method for determination of thermo-optical and spectroscopic parameters (thermal diffusivity, temperature coefficient of the optical path length change, pump and fluorescence quantum efficiencies, thermal loading, thermal lens focal length, etc) of relevance in the thermal lensing of end-pumped neodymium lasers operating at 1.06- and 1.3-mu m channels. The comparison between thermal lensing observed in presence and absence of laser oscillation has been used to elucidate and evaluate the contribution of quantum efficiency and excited sate absorption processes to the thermal loading of Nd: YAG lasers. (c) 2008 Optical Society of America.