Small Concessions Research Articles

Multi-objective Optimization for Green Delivery Routing Problems with Flexible Time Windows

ABSTRACT This paper presents a model and heuristic solution algorithms for the Green Vehicle Routing Problem with Flexible Time Windows. A scenario of new vehicle routing is analyzed in which customers are asked to provide alternative time windows to offer flexibility to help route planners find more fuel-efficient routes (“green delivery”). Customers can rank their preferred time windows as first, second, and third. The optimization model aims to reduce tour costs, promote electromobility over fossil fuels, such as diesel, and meet customer preferences when possible and affordable. The study incorporates a multi-objective optimization model with three objectives, which are overall cost, use of fossil fuel, and customer satisfaction. For the new problem, a set of realistic benchmark problems is created and four mainstream solvers are applied for the Pareto front approximation: NSGA-II, NSGA-III, MOEA/D, and SMS-EMOA. These algorithms are compared in terms of their effectiveness in achieving the objectives of minimizing travel costs, promoting electromobility, and meeting customer preferences. The study uses five different problems of single-vehicle route planning. Two major findings are that the selection of the metaheuristic can make a big difference in terms of algorithm performance. The resulting 3-D Pareto fronts reveal the nature of this new class of problems: Interestingly, in the new model with flexible time windows, most users can still be delivered in their most preferred time windows with only small concessions to the other objectives. However, using only one time window per user can lead to an increasingly drastic cost and fossil fuel consumption.

Codesign for Resilience and Performance

We present two optimization approaches to minimize the impact of sensor falsification attacks in linear time invariant systems controlled by estimate-based feedback. We accomplish this by finding observer and controller gain matrices that minimize outer ellipsoidal bounds that contain the reachable set of attack-induced states. To avoid trivial solutions, we involve a covariance-based <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\Vert H\Vert _{2}$</tex-math></inline-formula> closed-loop performance constraint. This exposes a trade-off between system security and closed-loop performance and demonstrates that only small concessions in performance can lead to large gains in our reachability-based security metric. We provide both a nonlinear optimization based on geometric sums and a fully convexified approach formulated with linear matrix inequalities. We demonstrate the effectiveness of these tools on two numerical case studies.

Disputes over intellectual rights in Brazil: interest organisations and their impacts on copyright law

Previous studies on lobbying outlined that business groups are more influential on low salient issues due to their organisation, unity, and expertise. This study addresses the causal mechanisms behind issue salience and business influence through an in-depth case study regarding copyright reform in Brazil. By employing a bibliographical and a documentary research, I analysed the statuses and legislative agendas of groups and other policy participants interested in either maintaining or changing copyright laws. Through the investigation of public hearings and draft bills discussed at a special committee of the Chamber of Deputies, I mapped the policy participants and their political preferences. Combining process-tracing and preference attainment, the analysis sought to identify the winners and losers in this debate as well as the strategies they implemented to achieve their goals. In contrast to other studies, the case under analysis revealed that certain participants acted as countervailing forces against powerful groups, though business organisations still succeed to achieve small concessions.

The Borderlands

The Borderlands

Our Pigs, Ourselves

Our Pigs, Ourselves

Study of Factors Influence on the Variability of Time for Consensus Building in Coalitions Based on Regular Markov Chains

Draft standard is approved if and only if consensus of the technical committee for standardization (TC) is ensured before its approval by the standardization body at the national, regional and international level. Previously published works of authors dedicated to the construction of a mathematical model of time to build a consensus (number of negotiations) in terms of variation in the number of TC members and their level of authoritarianism. The present study is a continuation of these works for the case of the formation of coalitions in TC. The mathematical model is constructed to ensure consensus on the work of technical standardization committees in terms of coalitions, which are overcome during the negotiation process by concessions. This paper analyzes the factors, which influence the time for consensus building in this case: the value of the assignment and an index of the effect of the coalition. It is proved that the time to build a consensus signifi-cantly depends on the value of unilateral concessions coalition and weakly depends on the size of coalitions with a fixed number of TC members. Built regression model of dependence of the average number of approvals from the value of the assignment. It was revealed that even a small concession leads to the onset of consensus, increasing the size of the as-signment results (with other factors being equal) to a sharp decline in time before the consensus. It is shown that the as-signment of a larger coalition against small coalitions takes on average more time before building a consensus. The factors influencing the variability of the number of concessions were investigated. The change in the root-mean-square deviation (RMS) of the time to build a consensus varies nonlinearly from small concessions Y=10% to large Y=75%, regardless of the ratio of the number of members between coalitions. In the simulations, at concessions Y=10% there is the largest variation among the number of consensuses in the experiments. Concession of the authoritarian leader in group reduces the number of negotiations and increases the quality of consensus. The results obtained are of practical value for all structures where the emergence of coalitions entails the impossibility of consensual decision-making and requires consideration of different ways to build a consensual solution.

Benchmarking and scalability of machine-learning methods for photometric redshift estimation

ABSTRACT Obtaining accurate photometric redshift (photo-z) estimations is an important aspect of cosmology, remaining a prerequisite of many analyses. In creating novel methods to produce photo-z estimations, there has been a shift towards using machine-learning techniques. However, there has not been as much of a focus on how well different machine-learning methods scale or perform with the ever-increasing amounts of data being produced. Here, we introduce a benchmark designed to analyse the performance and scalability of different supervised machine-learning methods for photo-z estimation. Making use of the Sloan Digital Sky Survey (SDSS – DR12) data set, we analysed a variety of the most used machine-learning algorithms. By scaling the number of galaxies used to train and test the algorithms up to one million, we obtained several metrics demonstrating the algorithms’ performance and scalability for this task. Furthermore, by introducing a new optimization method, time-considered optimization, we were able to demonstrate how a small concession of error can allow for a great improvement in efficiency. From the algorithms tested, we found that the Random Forest performed best with a mean squared error, MSE = 0.0042; however, as other algorithms such as Boosted Decision Trees and k-Nearest Neighbours performed very similarly, we used our benchmarks to demonstrate how different algorithms could be superior in different scenarios. We believe that benchmarks like this will become essential with upcoming surveys, such as the Vera C. Rubin Observatory’s Legacy Survey of Space and Time (LSST), which will capture billions of galaxies requiring photometric redshifts.

Retention of radiographers: A qualitative exploration of factors influencing decisions to leave or remain within the NHS

IntroductionIn many countries a widening imbalance exists between radiographer workforce supply and demand. Improving retention is a rapid method of workforce expansion which is gaining importance with policy makers and providers. To better understand the current leaver profile, this study aimed to identify why radiographers leave the NHS early, and what incentives are important in their decision to stay. MethodsA qualitative framework methodology used semi-structured telephone interviews to explore the perspectives of radiography managers, radiographers who have left the NHS, and those considering leaving. Purposive sampling ensured representation across radiography professional groups, geographical and organisational diversity, and stages of career. ResultsThree over-arching themes were identified across all radiographer professional groups (n = 44): 1) Challenging working patterns and the impact on employee health and wellbeing; 2) Lack of flexibility in working terms and conditions; 3) Lack of timely career progression and access to CPD, and the need to feel valued. Radiographers were keen to express how they ‘loved being a radiographer’; small concessions and changes to workplace culture might be the incentive to remain in radiography that some were clearly searching for. Manager participants recognised the need to offer greater flexibility in working patterns but this was challenging within financial and service delivery constraints. ConclusionsWhile some influencing factors varied between radiographer professional groups, the three themes were consistent across participants. Failure to address these concerns will exacerbate the loss of experienced and highly trained staff from the NHS at a time when demand for services continues to rise. Impact on practiceRecommendations are presented related to three primary themes which will be a catalyst for sharing of best practice between radiology and radiotherapy centres.

Understanding, Truth, and Epistemic Goals

Several argue that truth cannot be science’s sole epistemic goal, for it would fail to do justice to several scientific practices that advance understanding. I challenge these arguments but only after making a small concession: science’s sole epistemic goal is not truth as such; rather, its goal is finding true answers to relevant questions. Using examples from the natural and social sciences, I then show that scientific understanding’s epistemically valuable features are either true answers to relevant questions or a means thereof.

Does biodiversity benefit when the logging stops? An analysis of conservation risks and opportunities in active versus inactive logging concessions in Borneo

The island of Borneo is a biodiversity hotspot of global importance that continues to suffer from one of the highest deforestation rates in the tropics. Selective logging concessions overlay a third of the remaining natural forests in the Indonesian part of Borneo, but many of these concessions have become inactive in recent years. Whereas the cessation of logging could be beneficial to biodiversity, the absence of a logging company's presence in the forest could also leave the concession open to deforestation by other actors. Using remote sensing analyses, we evaluate 1) whether inactive concessions are more likely to suffer from deforestation than active ones, 2) the possible reasons why concessions become inactive, and 3) which inactive concessions hold the most potential for biodiversity conservation, if protected from deforestation. Our analysis shows that, counterintuitively, inactive concessions overall suffer a higher rate of forest loss than active ones. We find that small concession size and high elevation are correlated with inactive status. We identified several inactive concessions that, if maintained as natural forest, could significantly contribute to biodiversity conservation, as exemplified by their importance to two umbrella species: Bornean orangutan (Critically Endangered) and Sunda clouded leopard (Vulnerable). Because timber operations in other tropical regions are likely to experience similar cycles of activity and inactivity, the fate of inactive timber concessions and the opportunities they create for conservation deserve much greater attention from conservation scientists and practitioners.

Silk Stockings and Socialism: Philadelphia’s Radical Hosiery Workers from the Jazz Age to the New Deal by Sharon McConnell-Sidorick

Silk Stockings and Socialism: Philadelphia’s Radical Hosiery Workers from the Jazz Age to the New Deal by Sharon McConnell-Sidorick

Urban bus contractual regimes in small- and medium-sized municipalities: Competitive tendering or negotiation?

EU Regulation 1370/2007 promotes competitive tendering as the main mechanism for awarding the provision of urban bus services. However, small concessions can be awarded by means of a negotiated procedure. This paper seeks to evaluate the performance of urban bus operators in small- and medium-sized municipalities according to their prevailing contractual regimes. Three types of procurement procedure are analyzed: competitive tendering, negotiated contracts and contracts negotiated indirectly with the interurban bus provider. A translog stochastic cost frontier is conducted using a panel dataset (312 observations) over a nine-year period from 2007 to 2015 for the municipalities of the Barcelona province. In line with recent empirical evidence, we find no cost differences between the three contractual procedures. However, cost inefficiencies emerge in relation to the size of the municipality: the smaller the municipality, the greater the inefficiencies. As for ownership, there are no performance differences between private and other forms of delivery. Economies of density are no longer apparent at annual provisions above 300,000 vehicle-kilometers or in municipalities with more than 50,000 inhabitants. Therefore, the non-tendering option, as provided for under European Regulations for small concessions, gives the same results as that found for competitive tendering and indirectly negotiated procedures.

Fejezetek a Képzőművészeti Alap történetéből: a Tavaszi Tárlat és a „három T” a dokumentumok tükrében

Artists’ recollections of the Kadarist period of Hungarian socialism as well as the analyses of the cultural policy of the one-party state include as a permanent motif the “three T’s” for the initial letter of the Hungarian words for banning, toleration and support (tiltas, tűres, tamogatas) designed in theory for works and in practice applied partly to works and partly to artists. The reminiscing artists and the analysts are more or less at one declaring that “three T’s” were “created” by Gyorgy Aczel to describe the working of the art policy he dictated between 1957 and 1985. The matter is however far more complicated. First, the control of art policy was only partly in Aczel’s hand at the beginning of the period, and at that time there was no trace of the “three T’s”, but at most two were experienced: banning and support. Secondly, Aczel’s art policy was not solely his: the demarcation of his scope always fundamentally depended on the actual high political circumstances and on the party leaders who tri...

A Rent-Seeking Model of Voluntary Overcompliance

We provide an explanation for voluntary overcompliance, the phenomenon in which firms voluntarily choose to overcomply with environmental regulations. In our model, a polluting firm faces a rent-seeking contest with an environmental group. By making a small concession beforehand, i.e. by overcomplying voluntary, the firm lowers the stake the environmental group has in the rent seeking contest, which lowers the group’s lobbying effort in that contest. Voluntary overcompliance increases social welfare, yet the firm undersupplies overcompliance from a welfare point of view. An increase in the effectiveness of lobbying of the environmental group, increases the level of overcompliance.

Smith makes small concession in markup of COMPETES bill

Smith makes small concession in markup of COMPETES bill

Concerns remain over legal aid

The government's small concessions over plans to cut legal aid are not enough to protect children's access to justice, argues Anita Hurrell, legal and policy officer at Coram Children's Legal Centre

Continuous Mode Power Amplifier Design Using Harmonic Clipping Contours: Theory and Practice

A novel graphical power amplifier (PA) design tool, the “clipping contour,” is introduced and described. Using the now well-publicized continuous Class-B/J voltage waveform formulation as a starting point, a process is derived that allows contours to be constructed on a Smith chart that define the “zero-grazing” fundamental and harmonic impedance conditions. Theoretical equations are defined and solved whereby the contours can be drawn in real time in a computer-added design environment. A key and novel result from this theory is the definition of a 2-D harmonic design space that opens up rapidly as small concessions from optimum power and efficiency matching conditions are made. A design example is described and fabricated, which demonstrates the utility of using the second harmonic clipping contour during the PA design process. A 10-W GaN demonstrator gives measured continuous wave power > 8.5 W, efficiency > 60%, and better than -30-dB adjacent channel power ratio over a bandwidth of 1-2.9 GHz.

Can Schools Close the Gap?

How much effect can by themselves have on the persistent and corrosive learning gap between rich and poor? Not much, according to Diane Ravitch, whose writings I often admire. She recently told an audience of educators that the problem is poverty, not our schools (Carey, 2011, p. 14). A recent Kappan column echoes the sentiment: America does not have a general education crisis; we have a poverty crisis (Rebell & Wolff, 2012). Such remarks promote a dangerous complacency among those who believe that, on balance, our are doing well enough. These people insist that poverty, not schooling, should be our focus. Demography is destiny. Without doubt, poverty affects educational attainment. It is important then to fight for social justice, for programs we know will mitigate the effects of poverty. But must we buy into the notion that improvements to schooling can only have a marginal effect on the achievement gap? Absolutely not. The potential effect of better schooling becomes apparent the moment we take an unblinking look at how students actually spend time in school. Richard Rothstein is a compelling expositor of the notion that only societal changes can narrow the achievement gap. In a debate with Kati Haycock, president of the Education Trust, he argues that the purported gains on state tests aren't the result of better schooling but the result of test preparation and artful, state-level manipulation of cut scores and test item difficulty. As encouraging as these gains may look on paper, they don't truly reflect an increase in college readiness among low-income students, he said (Holland, 2007). Haycock does not deny this. But she cites numerous schools, districts, and whole states where improvements in teaching led to a significant reduction in the achievement gap, even according to NAEP scores, a more reliable measure of college readiness than state tests. As their exchange heats up, Rothstein makes small concessions, but then doubles down on his central argument: Improvements to schooling haven't had much effect on the real achievement gap--the one between those who are and aren't ready for college or post-secondary studies (Holland, 2007). Indeed, test score gains are not always a reliable indicator of substantial intellectual growth--of a kind that truly prepares students to succeed in college or other post-secondary studies. Schools affect learning When the dust settles, I'm convinced that there is indisputable evidence that improvements in schooling have a significant effect on student learning. But this would be even more true, not less, if we began to focus on precisely what Rothstein correctly defines as the real achievement challenge: truly equipping a larger proportion of students to succeed in college. When it comes to college readiness, Rothstein's pessimism overlooks a revealing feature of modern schooling: disastrous literacy practices. Our deep denial about this bears directly on our tepid estimations of how much effect can have on low-income populations. Fundamental changes to literacy practices will dramatically reduce the college-readiness gap, and in short order. Let's start with reading. Nothing is more important to college success than the ability to read well. But throughout K-12 schooling, the amount and complexity of students are required to do in a six-period school day is a scandal. When I ask my audiences, What are the two things you are least apt to catch students doing during the school day? Their immediate, almost choral response is reading and writing, followed by muffled laughter. Startling as it sounds, wrote Lucy Calkins and her colleagues, Students read for a remarkably small percentage of the day. It is not unusual, they found, for students to read for no more than 10 minutes during a 2 1/2 hour block (Calkins, Montgomery, & Santman, 1998, pp. …

Formation of spray cone of free jet during ejection of convoluted flow to the atmosphere

In modern world water-power, one of the predominant tendencies is to construct hydroprojects with high dams, which is associated with the necessity of solving a series of engineering and natural problems to ensure the safety of the water-development works. The building of reliable deepseated high-head water-passing structures can be classified as such a problem. Use of spiral spillways, equipped with helical gates is an effective means of its solution [1]. Helical gates (Fig. 1) in which smooth regulation of the flow being passed from zero to maximum is accomplished by rotating guide vanes, similar to the deflector of a reactive hydraulic turbine, have essentially no limit with respect to head. Beyond the spiral gate, the convoluted (circulating longitudinal) flow, which possesses, in addition to axial velocities u x directed along the conduit, azimuthal velocities u x , which are directed around its circumference and create a transverse circulation in the flow, proceeds into cylindrical discharge conduit (with a diameter 2R ). As a domestic development at the outset of the 1970s [2, 3], the vortical gates immediately gained the acceptance of specialists as one of the most reliable deep-seated high-head regulating gates. In addition, this design is considered excessively complex, and, consequently, expensive. In our opinion, the high cost of the equipment here is completely justified for purposes of reliability. If we are speaking of high heads, a small concession to quality may be transformed into not-so-small consequences. And experience indicates, the tendency to reduce the cost of the structures is accompanied by losses in their reliability, resulting in failures. The subject has acquired particular urgency in light of the return to the Rogun’ project, where construction of vortical spillways is specified. The reliability of the vortical gate lies within the principle of flow regulation by this device, which is achieved not only by throttling the water-passing opening, but also by varying the transverse circulation of the flow. By converting a significant or basic part of the mechanical energy of the flow into the energy of circulation movement and excess centrifugal pressure, they can then be extinguished over the length of the discharge conduit, or the flow can be atomized on ejection to the atmosphere. Offering little hydraulic resistance, the vortical gate accordingly exerts a minor influence on the flow, directing it easily past the rotating blades of the guide, and, in turn, experiencing a small reversing effect from the flow. Moreover, the rotating blades interacting with the flow are external to the periphery of the convoluted current that they are forming — in the zone where the high excess pressure of the centrifugal-force field suppresses

THE SLIPPERY SLOPE OF CONCESSION

We show that with common knowledge and a common rate of time preference, the potential loser can always avoid wasteful conflict through a time‐consistent series of small concessions. We examine how the failure of each of these assumptions may explain why conflicts arise. We also debate which actions may be helpful in such unfortunate circumstances.