Search

Copyright of Journal of Railway Science & Engineering is the property of Journal of Railway Science & Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

While commentators have long decried managerial short-termism, the deleterious effects of managerial short-termism on corporate social performance (CSP), and how to ameliorate those negative effects, remain underexplored. Specifically, due to the difficulty of unobtrusively measuring what is fundamentally a cognition in managers, empirical evidence at the organizational level of managerial short-termism's effect on CSP is relatively sparse. Here, we measure managerial short-termism by content analyzing firms' publicly filed annual reports (10-Ks). Using a combined dataset for 1,665 U.S. firms for the period 2000–2012, we show that managerial short-termism is negatively associated with CSP. However, we also show that this effect can be reduced through increased external monitoring by important stakeholders who value CSP. Specifically, we show that increasing dedicated institutional ownership and increasing analyst coverage both decrease the negative effect of managerial short-termism on CSP. We contribute to theory by predicting and showing the negative effect of managerial short-termism on CSP, and how external monitoring can reduce its deleterious effects. We contribute to practice by showing how this managerial cognition can be identified, and how its negative effects can be ameliorated, at the organizational level. [ABSTRACT FROM AUTHOR]

A variety of industries handling perishable goods is faced with the challenge of reducing lead times in order to ensure the best possible freshness of products at the point of sales. Considering a short-term multi-day planning horizon, the implementation of quantitative optimisation approaches with a continuous-time representation is most appropriate for planning and scheduling. However, as the quality measures are usually standardised by discrete grades, coordination take thresholds of maximum delivery times into account. For this purpose, a new mixed-integer linear programming model is developed. It enables to assess complete material flows, whose formal composition originates in a method based on power sets on the one hand, but additionally allows for the exact scheduling of partial material flows between sites. Specific transportation conditions that need to be imposed with respect to shelf-life are included. The efficiency of the model is confirmed by comparison with an equivalent mixed-integer linear formulation that uses path variables for modelling complete material flows. Besides an illustrative example motivated by the real-life problem of a fresh produce company supplying a wholesaler group, both model formulations are validated within a numerical analysis composed of 10 scenarios with different numbers of suppliers, warehouses, markets and product variants. Each scenario includes six instances with randomly generated data. As a result of the computations using high-performance hardware and software, it was shown that the formulation based on power sets was superior in each instance, as it enabled determining optimal solutions within significantly reduced computation times. [ABSTRACT FROM AUTHOR]

In short-term mine planning, mining scheduling is generally defined by designing dig-lines, allocated on benches. The mined ore will be sent to stockpiles, homogenization piles, or a concentration plant. The process to design dig-lines is usually done manually, whereby multiple simultaneous mining fronts are time-consuming and labour-intensive. The manual design of dig-lines tends to produce high variability of the grades throughout certain periods. Due to the limited time to manually multiple test dig-line design alternatives in short term planning, it is impossible to ensure production under stationary mean grades and variance. This article proposes an alternative to design short-term dig-lines, through an optimization process that joins and sequences the blocks in the block model over weeks or months, ensuring low variability of grades among periods. The methodology proposed generates multiple random paths starting at seed-points representing the locations and numbers of shovels previously selected by the mine planner. It tests multiple polygons representing a set of first dig-lines, comparing them with others, and keeping the dig-lines of low variability closer to a specific ore grade probability distribution, discarding the rest of the iterations. The process is repeated for the next dig-line. The block grades' probability distribution of all iterations is compared to a reference-grade histogram, and the iterations with the grade histogram more adherent are selected. Union-find and genetic algorithms were used to optimize the dig-lines aiming at the possible stationary grade distribution. The mean and variance of the reference model are 2.13% and 0.64%2, respectively. The mean for the automated draw dig-lines is closer to these values than the ones manually drawn. The method ensures more constant quality and quantity of ore production along a period planned, matching a target grade probability distribution. The methodology is illustrated using SiO2 values at a major iron ore mine. [ABSTRACT FROM AUTHOR]

Within business to business relationships it is not uncommon for some of the parties to be perceived as exercising power over others. A question that therefore needs to be addressed is why some parties appear to be willing to accept subservient roles. This paper will consider the possibility that an apparently subservient role may be acceptable to a party for two reasons. First, the party may not perceive their situation as being inequitable. Second, the party may believe that, at least in the short-term, there is no realistic alternative other than to accept a subservient role. [ABSTRACT FROM AUTHOR]

We compare the incidence, timing, and profitability of repeated online grocery purchases made by a cohort of consumers whose purchase intentions were measured with those of similar consumers whose intentions were not measured. We find that measuring intentions increases the likelihood of repeat purchase incidence and shortens the time until the first repeat purchase but that these two mere-measurement effects decay rapidly after 3 mo. Still, we find persisting gains in customer profitability over time because the accelerated purchases of the first 3 mo. lead to faster subsequent purchases in the remainder of the period. [ABSTRACT FROM AUTHOR]

This article is a direct response to a recent observation in the literature that managers appear to be short-term oriented in their assessment of the performance of an export venture (Madsen 1998). On the basis of a cross-national survey of exporting firms, the authors present a three-dimensional scale for assessing managerial judgment of short-term export performance (i.e., the STEP scale). The three dimensions are (1) satisfaction with short-term performance improvement, (2) short-term exporting intensity improvement, and (3) expected short-term performance improvement. The scale presents evidence of reliability as well as convergent, discriminant, and nomological validity, and it reveals factorial similarity and factorial equivalence across both samples. The authors outline managerial and public policy implications that stem from the scale and identify avenues for further export marketing research. [ABSTRACT FROM AUTHOR]

In this paper, the principal rewards an agent's farsighted effort both in the short and long term, with the short-term reward based on a noisy, forward-looking performance measure and the long-term reward based on a potentially less noisy, trailing performance measure. The main result is that optimal contracting weights depend on the agent's employment time horizon: the shorter the agent's employment horizon the greater the emphasis on the forward-looking performance measure and vice versa. This implies that contracting on forward-looking performance measures can be valuable in mitigating any adverse long-term effects of employees myopically focusing on short-term trailing performance measures. [ABSTRACT FROM AUTHOR]

Intraday data for weekly options are investigated for behavioral biases implied in prospect theory (PT) and cumulative prospect theory (CPT). The results generally support both theories, with losers (winners) observed to be relatively risk‐seeking (averse). On aggregate, losers (winners) overprice (underprice) their contracts and overweight (underweight) the probability of winning. Additionally, the volatility smirk observed in equity options is dampened by PT/CPT biases. The price distortions are time sensitive, especially for losing traders. Losers hold out by transacting later in the day and closer to expiration than their baseline counterparts. This betting‐time effect is absent among winners. [ABSTRACT FROM AUTHOR]

This study aims to investigate the influence of short-term portfolio investments and BI interest rate on fluctuation of rupiah exchange rate in Indonesia. The data used is quarterly data from 2010 to 2016 collected from Indonesia Central Bank. Using the Autoregressive Distributed Lag (ARDL) method, the result showed that rupiah exchange rate was strongly influenced by shocks in the private debt securities, joint stock price index, and BI Rate, both in the long run and short run. Moreover, it is found that there was a short-run and long-run balance relationship between Short Term Portfolio Investments and BI rate against the rupiah exchange rate. Thus, it is recommended that in order to stabilize the exchange rate, it is necessary to maintain the stability of short-term portfolio investments. [ABSTRACT FROM AUTHOR]

Contrary to the stereotype that the period between CEOs is a hiatus, interim and acting executives serve during an important strategic window. A model is presented to illustrate the dynamics of short-term leadership, including the precipitating circumstances for the temporary administration, the tasks of short-term leadership, and the moderating factors seen to affect the selection and success of the next chief executive. Researchers and practitioners are urged to consider more carefully the potential that a well-managed interregnum has to repair damage from a traumatic departure, buffer between administrations, and prepare the organization to accept and work with new leadership. [ABSTRACT FROM AUTHOR]

The article discusses the ways by which corporate performance measurement systems inhibit globalization. The authors discuss how global firms operate noting that they are able to react to changing market conditions and opportunities by reconsidering their options form a broad economic perspective and make decisions based on long run benefits. These organizations are able to operate with few self-imposed geographic or organizational constraints in conducting business. They then examine how accounting systems, with their inherent motive to avoid value-creating opportunities and measure short-term success, can restrain globalization due to the fact that the concept behind it is value creation and long-term success.

The time has come to make a comprehensive, critical assessment of the increasingly popular EAPs. To date, with very few exceptions, only glowing reports in the literature are available. This EAP literature is reinterpreted and methodological flaws are identified in analyzing usage patterns, legal issues, success rates, and cost-benefit calculations. The real and potential weaknesses and limitations need to be recognized in order to make EAPs more effective for the 1990s. [ABSTRACT FROM AUTHOR]

In recent years, below-the-line promotion has begun to shed its "Cinderella" image, and is starting to attract the sort of marketing budgets and academic attention that was previously only given to mass-media advertising. However, there is a general consensus that sales promotion is still neither managed effectively, nor understood thoroughly when compared to more high-profile above-the-line promotion. Improving the understanding and use of sales promotion will require academics and practitioners to analyse and understand each of the very different below-the-line techniques and their individual merits. This article is one of two which takes a detailed look at the use of sales promotion competitions. [ABSTRACT FROM AUTHOR]

The authors examine the relative importance of temporary price reductions, display alternatives, and newspaper advertising to unit sales of supermarket products. The research was conducted as an in-store pricing experiment characterized by a factorial design. [ABSTRACT FROM AUTHOR]

In many crucial decisions, the course of action that is moat desirable over the long run is not the best course of action in the short term. This is the dilemma addressed by the ongoing debate over economic "short-termism," sparked by contentions that U.S. firms are losing to overseas competitors because U.S. management is unwilling or unable to invest in the long run, I argue that the debate has suffered from a limited focus: to address this problem, I present a framework that addresses organizational and individual as well as economic perspectives. I offer a review of concepts, analysis, and evidence, and I suggest a cross-discipline, multilevel research agenda for advancing understanding of this vital topic. [ABSTRACT FROM AUTHOR]

Modern financial theory raises difficult issues for corporate strategy and public policy. Three such issues of significance to both theory and practice are delineated. Implications for researchers and practitioners are discussed. [ABSTRACT FROM AUTHOR]

This paper examines the associations between the adoption of a short-term compensation contract and changes in executive expenditure decisions for a sample of major commercial banks. In particular, the analysis concentrates primarily on changes in executive expenditures on discretionary items (expenditures preferred more by the manager than by shareholders). The results indicate that the adoption of a short-term compensation plan is associated with modest decreases in the ratio of discretionary expenditures to current operating revenue and the ratio of discretionary expenditures to managerial compensation for banks making the contractual change. These results are consistent with the conclusion that the mix of discretionary expenditures and effort selected by the manager changes with the adoption of a short-term compensation contract. [ABSTRACT FROM AUTHOR]

We examine managerial investment decisions in the presence of imperfect information and short-term managerial objectives. Prior research has argued that such an environment induces managers to underinvest in long-run projects. We show that short-term objectives and imperfect information may also lead to overinvestment, and we identify how the direction of the distortion depends upon the type of informational imperfection present. When investors cannot observe the level of investment in the long-run project, suboptimal investment will be induced. When investors can observe investment but not its productivity, however, overinvestment will occur. [ABSTRACT FROM AUTHOR]

In “Managerial Incentives for Short-Term Results,” Narayanan examines the manager's incentive to make a suboptimal decision, in particular an incentive to choose projects that yield short-term profits even when the manager is compensated with a long-term contract. This incentive to act myopically at the expense of shareholders' welfare is attributed to the manager's very concern for the long-term impact of current actions, that is, the desire to “enhance reputation earlier” to boost wages. Although this type of myopic behavior is a cause for great concern and Narayanan's approach is interesting, the particular model he develops has a serious drawback. We discuss briefly in this note how the shareholders can easily anticipate and prevent the manager from making a suboptimal decision by providing proper incentive contracts. [ABSTRACT FROM AUTHOR]

Of late, concern has been expressed that American managers tend to make decisions that yield short-term gains at the expense of the long-term interests of the shareholders. In this paper, we have attempted to investigate managerial incentives for such decisions. We find that, when the manager has private information regarding his or her decisions, there exist situations wherein the manager has incentives to make decisions which yield short-term profits but are not in the stockholders best interests. This incentive for suboptimal decisions arises because the manager, by taking decisions yielding short- term profits, hopes to enhance his reputation earlier, thus boosting his wages. We also find that this incentive is inversely related to her experience, the duration of her contract, and the risk of the firm. [ABSTRACT FROM AUTHOR]

The article presents an exploration into the accounting factors of attributable cost and its derived quantitative policy decision models. A conceptual definition of quantitative policy decision making is provided, highlighting its difference from short-term analysis as well as investment-based long-term planning. Several manifestations of cost accounting are discussed, including short-run variable and fixed costs, as well as long-run marginal and full costs. The placement of attributable cost within the previously illustrated frameworks is delineated, citing its flexibility and measurement criteria. Concluding comments are given advocating the inclusion of attributable costing within the wider framework of long-term planning.

A stochastic model that generates data for sales planning and control is described. An example is presented that shows how these data are used to plan short-run sales activities and train effective salesmen. In the model, changes in customer propensities to buy are treated as Markov processes. Finally, it is suggested that the concepts developed here may be computerized and integrated into existing systems for planning and control. [ABSTRACT FROM AUTHOR]

This article is a nontechnical description of a generalized marketing model from the point of view of the manufacturer of nondurable goods, one who does not fully control his own distribution system. The model seeks to identify the main marketing variables affecting the sales of such products. These are arranged in a structure which offers a useful conceptual approach for marketing management and a starting framework for a specific information-system design. Mr. Barton believes that it is technically feasible to collect input statistics with sufficient accuracy as to improve the marketing activities of many medium-size to large-size companies. [ABSTRACT FROM AUTHOR]

The potential contributions of short-term sales forecasts to production economies are often overlooked. The short-term behavior of the manufacturer's shipments can be anticipated with accuracy once the constant interaction of the sales of stock-carrying intermediaries, the changes of inventories of such intermediaries, and the order pattern of such intermediaries are known and understood. The volume of sales during a 3-month forecast period is largely determined by events which occurred prior to the beginning of the forecast period. If accurate information on all past events of importance is available, reliable forecasts can be produced. [ABSTRACT FROM AUTHOR]

The article discusses changes to corporate budgets which are typically implemented in times of economic downturn, and offers reasons why contrarian policies could produce superior results. The budget items addressed are advertising and employee benefits. Historical evidence is cited that firms which increase advertising during a recession profit greatly as a result. A similar case is made for employee benefits. It is said that a misguided focus on immediate cost savings overlooks the significance of competitive advantage.

Research Summary: Combining studies on real options theory and economic short‐termism, we propose that, depending on CEOs’ career horizons, CEOs have heterogeneous interests in strategic flexibility, and thus, have different incentives to make real options investments. We argue that compared to CEOs with longer career horizons, CEOs with shorter career horizons will be less inclined to make real options investments because they may not fully reap the rewards during their tenure. In addition, we argue that long‐term incentives and institutional ownership will mitigate the relationship between CEOs’ career horizons and real options investments. U.S. public firms as an empirical setting produced consistent evidence for our predictions. Our study is the first to theoretically explain and empirically show that a CEO's self‐seeking behavior will impact real options investments. Managerial Summary: This article helps to explain how a CEO's self seeking‐behavior may shape a firm's real option investment, which could result in different level of strategic flexibility. We argue that CEOs with short career horizons have less time to exercise their firms’ real options, which should lower the investments in the firms’ real options portfolios relative to CEOs with long career horizons. We study a sample of U.S. public firms and find strong evidence that a CEO's expected tenure in the firm is positively related to the real options investments at the firm level. We find that this agency issue can be mitigated by adopting appropriate corporate governance mechanisms such as long‐term incentives and institutional investors. [ABSTRACT FROM AUTHOR]

In this excerpt from his forthcoming book, A Cure for Corporate Short‐Termism, the author begins by noting that many corporate management teams "unwittingly foster a culture of short‐termism" that ends up reducing the long‐run value of their companies. Such a culture starts with the process that surrounds quarterly earnings, in which managers seek to "guide" and then beat the analysts' consensus for EPS. But even if the market seems to deal harshly with companies that "miss" consensus, the author's own research shows that when viewed over periods of a year or more, it is the changes in earnings and cash flows that drive returns for shareholders, and not management's consistency in meeting the analysts' expectations. What's more, this process of managing expectations—which the author calls "sandbagging"—goes on not only between companies and their investors, but also between corporate headquarters and the unit managers in annual budgeting that is often used to set incentive plan targets. According to the author, such sandbagging may be "the worst managerial behavior problem facing U.S. public companies." Measuring managers' performance against plan as the basis for their bonuses gives them strong incentives to understate the expected profitability and growth of their businesses. And the predictable result is mediocre plans that can be easily beaten—not a prescription for outstanding performance. Compounding the problem, many companies these days focus heavily on improving returns on capital or equity, and other efficiency measures, and much less on growth. But as the author emphasizes, encouraging the managers of already high‐return businesses to increase or "maximize" their returns is a sure prescription for underinvestment. (After all, if you're already earning 40% on capital, taking on projects that are expected to earn anything less will reduce your average return—and with it your bonus.) The proposed solution—which is presented in detail in later chapters of the book—is a corporate performance measurement and reward system based on a measure of economic profit called "residual cash earnings," or RCE, which is based on cash earnings less a capital charge on gross investment. Such a measure has the virtue of spreading the NPV out more smoothly over the life of an investment, which allows value‐creating investments to drive up the measure much more quickly than with traditional return and economic profit measures. And by tying their managers' bonuses to, say, annual increases in RCE, such a system can help companies accomplish a number of goals: (1) get more reliable budgets (by eliminating any incentive for sandbagging) from their unit managers; (2) encourage smaller capital requests from low‐return businesses, but larger requests from high‐return businesses; (3) limit the corporate tendency to succumb to "herding" and "recency bias," as reflected in massive overinvestment at the tops of business cycles and far too little investment at the bottoms; and (4) create and reinforce a longer‐term focus and ownership culture of accountability in which managers throughout the organization participate in and assume responsibility for their decisions and performance. [ABSTRACT FROM AUTHOR]

In this edited version of her keynote address at the Financial Management Association's Annual Conference last October, the author begins by noting that shareholder turnover in U.S. public companies has increased sharply during the past four decades, rising from a low in the mid‐1970s of around 10%—which implies an average holding period of 10 years—to its current level of over 350%, or a holding period of some three or four months. But this increase in average share turnover in recent decades has also been accompanied by a remarkable growth of long‐term investors. In a recent study, the author and two colleagues used quarterly holdings information from Form 13F to identify short‐term investors—which they defined as having annualized turnover rates over 100%, implying a holding period of less than a year—and long‐term investors—those with a turnover rate below 33%, with holding periods longer than three years. Defined in this way, the presence of long‐term institutional investors in the average public company's shareholder base has more than doubled since the early 2000s. What's more, in an attempt to determine whether the market encourages corporate short‐termism by putting too high a discount rate on—and so under‐valuing—earnings or cash flows that are expected to appear in the distant future, the author points to the findings of two studies by others. In the first of the two, an examination of the pricing of a relatively new derivative known as "dividend strips" shows that the implied discount rate for such "incremental" dividends has actually been higher than the rate applied to the long‐term residual value, suggesting that the market undervalues near‐term cash flows relative to more distant ones. The second of the two cited studies reports that companies with high levels of R&D spending—in other words investments with distant payoffs—are fairly priced in the sense that their future stock returns are comparable to those earned by other companies in the same risk class. In response to the claim that shareholder activists force companies to pursue near‐term profits at the expense of the corporate future, the author cites her own study (with two colleagues) that examines the stock returns of targeted companies from three years before the announcement of an activist's taking a position in the stock to three years after. What they find is that the targets significantly underperformed the market and their competitors in the period leading up to the activists' involvement—and that, after a 5% jump in share prices in response to the announcement, the average performance of the targets was roughly equivalent to their competitors' during the next three years. And, as if reflecting this 5% net gain, the operating performance of these companies, as measured by ROA, improved significantly during this three‐year period. To be sure, there is some evidence that activists discourage corporate R&D. But, as the author (and her three co‐authors) shows in a study published this past year in the Journal of Financial Economics, although corporate spending on R&D does fall (by an average of $15 million per company) in the year following the appearance of activists, R&D as a percentage of total assets remains unchanged, reflecting the tendency of companies to sell assets; and the smaller R&D function becomes more productive, accounting for 15% increases in both new patents and citations during the next three years. [ABSTRACT FROM AUTHOR]

Today's widespread criticism of U.S. companies as shortsighted and ever willing to sacrifice their future for near‐term profit is by no means new. As the author of this article shows, such charges of short‐termism have a long history that goes back at least 40 years. But as he goes on to point out, if these claims were warranted, then the effects we have been warned about all these years would surely have shown up by now. But it is difficult to find evidence of such effects. For example, a short‐term orientation has not been reflected in any erosion of corporate profitability over time. As the author reports, the ratio of U.S. corporate profits as a percentage of U.S. GDP has not only been on a generally upward trend since the early 1980s, but has never been higher than in the past few years. And corporate spending on R&D has also gone up sharply during this period, from 1.1% of GDP in 1977 to 1.7% in 2016. What's more, evidence of short‐termism has not shown up in either higher amounts of investment, or higher rates of return, by venture capitalists and private equity firms, which are both in a good position to profit from widespread corporate failure to pursue valuable growth opportunities. Nor do stock market investors appear to encourage corporate short‐termism, given their willingness to fund IPOs of companies with no previous earnings, and to assign high price‐earnings multiples to companies, like Amazon and Tesla, whose reported earnings have been modest at best. What's more, the fact that today's P/E and CAPE ratios are at relatively high levels suggests that the market continues to expect significant rates of growth by U.S. companies. Some critics, to be sure, have argued that the high level of corporate buybacks and other distributions of cash, when combined with today's near‐record corporate cash holdings, provide clear evidence of a widespread failure of companies to invest in their future. But as the author notes, such distributions in fact represent a fairly small fraction—only around 20%—of after‐tax corporate net income after infusions of new debt and equity capital are also taken into account. [ABSTRACT FROM AUTHOR]

Objectives: The lack of access to diagnostic imaging in resource-limited settings (RLSs) poses a worldwide problem. Advances in ultrasound (US) imaging technology bridge this gap, particularly when examinations are performed by physicians and integrated into the patient encounter, termed point-of-care ultrasound (POCUS). Because the number of physicians participating in short-term medical missions (STMMs) is increasing, the authors sought to characterize how the use of POCUS would affect care delivered as part of a 1-week outreach trip in rural Nicaragua.Methods: In February 2017, as part of an ongoing collaboration among the University of South Carolina, the Medical University of South Carolina, and OneWorld Health, the authors conducted an observational prospective study of all of the patients who received a POCUS examination as part of standard clinical practice during an STMM to Sébaco, Nicaragua. The goal was to determine how often POCUS changed medical management. In addition, the number and types of scans performed were recorded to assess the most common reasons for POCUS use.Results: More than 1100 patients were seen, and a total of 79 POCUS examinations were performed on 59 patients by 2 physicians with extensive POCUS training. Eighty percent of the patients were women, with an average age of 40.5 years (range 1.6-87 years). The use of US changed management for 35.6% of total patients examined (N = 21), divided among changes in diagnosis, pharmacotherapy, new referral, or referral not needed. The average time to perform a POCUS examination was 6.0 minutes. A wide range of POCUS examinations were performed, with lung, gallbladder, obstetric/gynecologic, and cardiac examinations performed most often.Conclusions: Incorporating POCUS by trained physicians in an RLS as part of an STMM was successful and often changed management. As interest in nonemergency and noncritical care POCUS increases and proliferation of low-cost, accurate, handheld US devices continues, it is probable that more physicians traveling to RLSs will use POCUS as part of STMMs, positively affecting patient care. [ABSTRACT FROM AUTHOR]

The optimal operation strategy of active distribution networks is investigated by this paper. The energy storage system (ESS) and distributed generation (DG) are utilized in the proposed planning. The paper presents two-level planning including short term and long term planning. The long term planning installs ESSs and diesel DGs on the network and the short term one determines an hourly optimal operation strategy for ESSs and diesel DGs. Different types of DG including solar photovoltaic (PV), wind, and diesel are studied at the same time. The objective function of the planning is to minimize annual operation cost of distribution network subject to security constraints of the network. The uncertainty of solar-wind units is estimated by many scenarios and stochastic programming is carried out to solve the problem. The proposed problem is expressed as a nonlinear mixed integer programming and solved by modified PSO algorithm. In order to cope with the real conditions, reactive power of ESSs and diesel DGs are included in the problem. Depth of discharge is also considered as a design variable and optimized for ESSs. The planning optimizes a large number of design variables at the same time including size and location of ESSs and diesel DGs, daily operation of diesel DGs, daily charging-discharging pattern of ESSs, and optimal depth of discharge for ESSs. The results demonstrate that the proposed two-level planning can effectively reduce cost and losses as well as increase efficiency and performance of the network. [ABSTRACT FROM AUTHOR]

The current study examined the effect of simple complementary auditory feedback (CAF) on performance and performance strategies in a puzzle completion task. Fifty-three undergraduate students were randomly assigned to one of two training groups: a CAF group, which received simple auditory feedback during the task; and a Control group, which did not receive the auditory feedback. The difference between the higher and lower achievers (in terms of time needed to complete the puzzle) was larger in the CAF group compared to the Control group. As for performance strategies, participants in the CAF group engaged less in strategies which involved pre-planning (for example, separating out edge pieces) and focused more on trying to maximize short-term achievements (for example, through trial and error). The findings suggest that CAF which entails low-level feedback is not recommended for weaker performers, for whom it promotes less-effective strategies focused on short-term goals. [ABSTRACT FROM AUTHOR]

Large hydro basins are difficult to optimally operate, due to extended water travel times, numerous tributaries to the same reservoir, uncertainties in the water inflows and different characteristics and efficiencies of the hydro plants. Also, optimal management must consider ecological restrictions, guarantying legal and social requirements. This paper proposes an advanced optimization tool, improving economic profits while meeting European and local regulations. Nonlinear relationships between efficiency, height and stored water are represented through piecewise linear functions, without requiring integer variables. Uncertainties in the water inflow and large travel times are considered by using stochastic scenarios. The Guadalquivir Basin, in southern Spain, with 18 reservoirs, a minimum of 50 h between head and mouth of the considered section and strong flow restrictions is analyzed in the study. Results show the robustness of the model and the validity of statistical studies for short-term studies, given a large chain of reservoirs, dry circumstances and strong operation constraints. [ABSTRACT FROM AUTHOR]

Many companies operate assessment centers to help them select candidates for open job positions. During the assessment process, each candidate performs a set of tasks, and the candidates are evaluated by some so-called assessors. Additional constraints such as preparation and evaluation times, actors’ participation in tasks, no-go relationships, and prescribed time windows for lunch breaks contribute to the complexity of planning such assessment processes. We propose a multi-pass list-scheduling heuristic for this novel planning problem; to this end, we develop novel procedures for devising appropriate scheduling lists and for generating a feasible schedule. The computational results for a set of example problems that represent or are derived from real cases indicate that the heuristic generates optimal or near-optimal schedules within relatively short CPU times. [ABSTRACT FROM AUTHOR]

We present the results of short-term forecasting of Henry Hub spot natural gas prices based on the performance of classical time series models and machine learning methods, specifically; neural networks (NN) and strategic seasonality-adjusted support vector regression machines(SSA-SVR). We introduce several improvements to the forecasting method based on SVR. A procedure for generation of model inputs and model input selection using feature selection (FS) algorithms is suggested. The use of FS algorithms for automatic selection of model input and the use of advanced global optimization technique PSwarm for the optimization of SVR hyper parameters reduce the subjective inputs. Our results show that the machine learning results reported in the literature often over exaggerate the successfulness of these models since, in some cases, we record only slight improvements over the time series approaches. We have to emphasize that our findings apply to Henry Hub, a market which is known among traders as the “widow maker”. We find definite advantages of using FS algorithms to preselect the variables both in NN and SVR. Machine learning models without the preselection of variables are often inferior to time-series models in forecasting spot prices and in this case FS algorithms show their usefulness and strength. [ABSTRACT FROM AUTHOR]

Self-financing is the basis of any enterprise development. Equity capital is also an essential source of the enterprise. Funding issues are crucial to the survival and development of the enterprise. First of all, the company must have liquidity to deal with the assumed commitments, that is to honour the due debt in the near future, thus ensuring its short-term financial balance. Secondly, on the part of the enterprise, it is the issue of launching in any kind of investments that will make the company's possibilities develop. In this case, it is the financing of the medium and long-term development, which conditions the increase of the results in the future and the maintenance of the financial equilibrium [ABSTRACT FROM AUTHOR]

The application of real-time precise point positioning (PPP) requires real-time precise orbit and clock products that should be predicted within a short time to compensate for the communication delay or data gap. Unlike orbit correction, clock correction is difficult to model and predict. The widely used linear model hardly fits long periodic trends with a small data set and exhibits significant accuracy degradation in real-time prediction when a large data set is used. This study proposes a new prediction model for maintaining short-term satellite clocks to meet the high-precision requirements of real-time clocks and provide clock extrapolation without interrupting the real-time data stream. Fast Fourier transform (FFT) is used to analyze the linear prediction residuals of real-time clocks. The periodic terms obtained through FFT are adopted in the sliding window prediction to achieve a significant improvement in short-term prediction accuracy. This study also analyzes and compares the accuracy of short-term forecasts (less than 3 h) by using different length observations. Experimental results obtained from International GNSS Service (IGS) final products and our own real-time clocks show that the 3-h prediction accuracy is better than 0.85 ns. The new model can replace IGS ultra-rapid products in the application of real-time PPP. It is also found that there is a positive correlation between the prediction accuracy and the short-term stability of on-board clocks. Compared with the accuracy of the traditional linear model, the accuracy of the static PPP using the new model of the 2-h prediction clock in N, E, and U directions is improved by about 50%. Furthermore, the static PPP accuracy of 2-h clock products is better than 0.1 m. When an interruption occurs in the real-time model, the accuracy of the kinematic PPP solution using 1-h clock prediction product is better than 0.2 m, without significant accuracy degradation. This model is of practical significance because it solves the problems of interruption and delay in data broadcast in real-time clock estimation and can meet the requirements of real-time PPP. [ABSTRACT FROM AUTHOR]

The liberalization of the power markets gained a remarkable momentum in the context of trading electricity as a commodity. With the upsurge in restructuring of the power markets, electricity price plays a dominant role in the current deregulated market scenario which is majorly influenced by the economics being governed. In the deregulated environment price forecasting is an important aspect for the power system planning. The problem of price forecasting can be entirely viewed as a signal processing problem with proper estimation of model parameters, modeling of uncertainties, etc. Among the different existing models the artificial neural network based models have gained wide popularity due their black box structure but it too has its own limitations. In the proposed work in order to overcome the limitations of the classical artificial neural network model, generalized neuron model is used for forecasting the short term electricity price of Australian electricity market. The pre-processing of the input parameters is accomplished using wavelet transform for better representation of the low and high frequency components. The free parameters of the generalized neuron model are tuned using environment adaptation method algorithm for increasing the generalization ability and efficacy of the model. [ABSTRACT FROM AUTHOR]

This article determines the condition under which recommendation changes relative to consensus recommendation and recommendation changes relative to analyst’s previous recommendation are valuable. We show that recommendation upgrades (downgrades) relative to consensus recommendation are followed by significantly positive (negative) short-term returns whenever consensus recommendation represents convergence of analysts’ opinions. We also show that as the standard deviation associated with consensus recommendation increase, the value of recommendation changes reduce significantly. This article also shows that recommendation upgrades (downgrades) relative to analyst’s previous recommendation are followed by significantly positive (negative) short-term returns whenever interval between two consecutive recommendations is relatively short. We also show that, as the interval between two consecutive recommendations increase, the value of recommendation changes reduce significantly. Our results are robust across various subsamples based on size and region. [ABSTRACT FROM PUBLISHER]