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We consider the problem of a project manager of a matrix organization responsible for the timely completion of projects arriving over time and requiring the usage of a set of resources under his/her purview. A project is defined by a set of activities, precedence relations between activities, resource requirements, a customer due date, and a priority (a weight). Arriving projects are released to a flow control system that monitors the progress of activities and schedules the set of available activities, i.e., activities that are ready to be processed, as appropriate. A critical feature of such control systems is the decision process for choosing the next activity to seize a given resource. This is the focus of this paper. In the past several decades, various heuristic priority rules have been proposed in the literature to support this type of decision in differing settings such as the job shop problem and the deterministic resource-constrained project scheduling problem. A gap exists with respect to testing the various rules all together in the more realistic dynamic-stochastic multi-project environment when the objective is to minimize weighted project tardiness. The purpose of this paper is to fill this gap. Results show that the priority rule "Weighted Critical Ratio and Shortest Processing Time" (W (CR + SPT)) is the best performing rule with respect to minimizing weighted project tardiness. W (CR + SPT) is shown to be a variant of the family of "Modified Due Date" rules first introduced by Baker and Bertrand (J Oper Manage 1(3):37–42, 1982). Repeated application of Duncan's Multiple Range test demonstrates the robustness of our findings. For the environmental parameters (due date tightness, variation of expected activity durations, and utilization of resource), the W (CR + SPT) rule is dominant with respect to weighted project tardiness among the eleven priority rules tested. Only when the number of resources is very modest (either 1 or 3 resources) or under a purely parallel resource network is W (CR + SPT) not the dominant rule. In those cases, its variant W (CR + GSPT) is the best performing rule with respect to weighted project tardiness. [ABSTRACT FROM AUTHOR]

Duration, cost, and resources are defined as project constraints. Consequently, in each project, one of these constraints is received attention compared with another. Thus, the abilities of construction project manager should include balancing these constraints in a way that all the project objectives are fulfilled. Achieving this balance is conducted by determining the best alternative for each activity, while minimizing project total cost and duration and satisfies resources constraints as well as smoothing resource histograms. For that purpose, this study aims at optimizing project schedule to provide this balance by using multi construction methods which is mainly based on multiskilling strategy. As will be discussed, to achieve this goal, a model was developed and genetic algorithm is used to preform optimization. This study contributes to the body of knowledge a model able to produce schedules with appropriate project duration, cost, and quality, also satisfy resource constraints with most leveled histograms.

Duration, cost, and resources are defined as constraints in projects. Consequently, Construction manager needs to balance between theses constraints to ensure that project objectives are met. Choosing the best alternative of each activity is one of the most significant problems in construction management to minimize project duration, project cost and also satisfies resources constraints as well as smoothing resources. Advanced computer technologies could empower construction engineers and project managers to make right, fast and applicable decisions based on accurate data that can be studied, optimized, and quantified with great accuracy. This article strives to find the recent improvements of resource-scheduling problems and time-cost trade off and the interacting between them which can be used in innovating new approaches in construction management. To achieve this goal, a state-of-the-art review, is conducted as a literature sample including articles implying three areas of research; time-cost trade off, constrained resources and unconstrained resources. A content analysis is made to clarify contributions and gaps of knowledge to help suggesting and specifying opportunities for future research.

Introduction: National medicines regulatory agencies are faced with challenges including limited resources and technical capacity, resulting in countries collaborating and sharing resources to improve efficiency of the review process to facilitate access to quality-assured medicines by their populations. One such collaboration is the Southern African Development Community (SADC) medicines registration collaborative initiative, ZaZiBoNa. Countries participate in the initiative by contributing to regulatory reviews and good manufacturing practices inspections. The aim of this study was to review and compare the registration processes of regulatory authorities of Mozambique, Namibia, South Africa, Tanzania, Zambia, and Zimbabwe to identify strategies for better alignment.Methods: A senior member of the division responsible for issuing marketing authorisations completed an established and validated questionnaire, which standardises the review process, allowing key milestones, activities and practices of the six regulatory authorities to be identified and compared. The completed questionnaires were validated by the heads of the respective agencies.Results: The six countries vary in population and in the size of their respective regulatory agency and the resources allocated to regulatory reviews. The review processes of the six agencies were similar; however, differences were noted in the milestones recorded; for example, two of the countries did not record the start of the scientific assessment. Additionally, decisions for marketing authorisation were made by an expert committee in four of the countries and by the head of the agency and the Minister of Health in two countries. All six agencies implemented the majority of good review practices; however, the need for improvement in the areas of transparency and communication and quality decision making practices was a common finding for all six countries.Conclusions: Participation in the ZaZiBoNa initiative has improved the way in which the six agencies perform regulatory reviews in their countries, highlighting the realisation of one of the key objectives of the initiative, which was building the expert capacity of member countries. Other agencies in the SADC region and beyond can use the results of this study to identify best practices, which in turn, could improve their regulatory performance.

Overlapping coalition formation (OCF), which provides a natural framework for modeling scenarios where each agent can join and allocate their resources to several completely different coalitions at the same time, has become a very active topic in multiagent systems. For OCF in resource-constrained and subadditive task oriented domains, an agent may not possess sufficient resources to meet the needs of multiple coalitions simultaneously. As a result, there may exist many potential resource conflicts among the rival overlapping coalitions. To tackle such situations, we first present a natural variation of the traditional OCF model and analyze the size of the solution space and the computational complexity of the overlapping coalition structure generation (OCSG) problem. Next, we develop a generic task-oriented heuristic (TOH) for individual repairs that can be used in binary meta-heuristic algorithms to generate overlapping coalitions in a parallel manner. Moreover, we show how the proposed TOH repairs a 2-D individual to resolve resource conflicts and discuss several basic properties. Finally, to evaluate the effectiveness of TOH, we compare it with the existing agent-oriented heuristic for the OCSG problem. The empirical results demonstrate that TOH is of high efficiency and effectiveness in harsh environments with fierce competition over scarce resources. [ABSTRACT FROM AUTHOR]

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Copyright of Accounting Perspectives is the property of Canadian Academic Accounting Association 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.)

Duration, cost, and resources are defined as project constraints. Consequently, in each project, one of these constraints is received attention compared with another. Thus, the abilities of construction project manager should include balancing these constraints in a way that all the project objectives are fulfilled. Achieving this balance is conducted by determining the best alternative for each activity, while minimizing project total cost and duration and satisfies resources constraints as well as smoothing resource histograms. For that purpose, this study aims at optimizing project schedule to provide this balance by using multi construction methods which is mainly based on multiskilling strategy. As will be discussed, to achieve this goal, a model was developed and genetic algorithm is used to preform optimization. This study contributes to the body of knowledge a model able to produce schedules with appropriate project duration, cost, and quality, also satisfy resource constraints with most leveled histograms. [ABSTRACT FROM AUTHOR]

Relevant costing is a management accounting term that relates to focusing on only the costs relevant to a specific decision being made. It simplifies the decision-making process as it ignores cost data that is irrelevant, or will not have an impact on the specific decision being made. This study adopts an observation of quantitative methodology with primary and secondary data in view of the nature of the analysis. Relevant costing is often used in short-terFm decision making and a number of specific practical examples are illustrated in this study. This study has been designed to achieve the objective of assessing the level of perceptions of four areas such as (i)making & buying, (ii) dropping or retaining a segment, (iii) constrained resources and (iv) special orders in using relevant costing in Ready-made Garments Industry (RMG) of Bangladesh. To attain this objective total 100 sample respondent company from Ready-made Garments Industry (RMG) have been randomly selected. By using variance analysis, authors have found that all four factors have significant influence in using relevant costing. Last, the result of this study suggests that the strengthening the decision-making mechanism required a strong relevant costing benefits and its proper application.

This paper is motivated by, but not limited to, the task of scheduling jobs organized in workflows to a computational grid. Due to the dynamic nature of grid computing, more or less permanent replanning is required so that only very limited time is available to come up with a revised plan. To meet the requirements of both users and resource owners, a multi-objective optimization comprising execution time and costs is needed. This paper summarizes our work over the last six years in this field, and reports new results obtained by the combination of heuristics and evolutionary search in an adaptive Memetic Algorithm. We will show how different heuristics contribute to solving varying replanning scenarios and investigate the question of the maximum manageable work load for a grid of growing size starting with a load of 200 jobs and 20 resources up to 7000 jobs and 700 resources. Furthermore, the effect of four different local searchers incorporated into the evolutionary search is studied. We will also report briefly on approaches that failed within the short time frame given for planning.

This case provides students with an opportunity to utilize cost volume profit (CVP) analysis tools in a contextually rich environment of a microbrewery. The case explores basic CVP concepts as well as decision making for constrained resources, make versus buy, and new product development. Further, the case requires quantitative analysis, understanding, and exploration of contextual issues as well as assessment of qualitative factors. While directed at graduate students (M.B.A. and E.M.B.A.) in a managerial accounting course, this case may also be suitable for undergraduate students with some minor modifications. [ABSTRACT FROM AUTHOR]

In this letter, we study the effect of single on-ramp with constrained resources on the density of asymmetric simple exclusion processes (ASEPs) by theoretical analysis and extensive computer simulations. Here, the on-ramp reservoirs and the system must share a finite supply of particles. It is found that the average particle density of the system can be expressed as a function of the on-ramp rate and the total number of particles. The result shows that the availability of particles becomes a rate-limiting factor for transport problems. [ABSTRACT FROM AUTHOR]

Private sector, high-resolution, daily-updated satellite assets have become a significant resource for remote sensing operations. A case in point is PlanetScope (PS), currently operating the largest collection of small Earth-imaging satellites. This paper discusses the opportunities and limitations of PS assets to monitor land cover change under resource constrained research environments typical of emerging economies in the tropics in the context of the Alas Merta Jati in Central Bali. Land cover information can be extracted from multiscale imagery for fine-scale to coarse-scale insights based on spatial resolution; Landsat offers coarse, Sentinel2 medium and PS fine spatial resolution (table 1). Additionally, analysis tasks are impacted by the number of sensor spectra available, where fewer spectral bands generally compromise classification opportunities. Moreover, land cover and land use analysis in Bali's Alas Merta Jati have in the past been limited by a lack of appropriate data sources. Only in 2000 did the situation improve with the introduction of image data from Landsat 7 and 8. While Landsat offers amongst the three sources the deepest view into remote sensing history, Landsat bands B, G, R, NIR, SWIR1, SWIR2 have a spatial resolution of only 30 meters and are applicable to land cover and land use interpretation only at a coarse scale. The Sentinel2 network offers similar spectral coverage and a higher spatial resolution of 10 meters, with a combined revisit frequency of 5 days as opposed to Landsat's 16-day revisit cycle. Since 2016, the PS network has significantly improved the state of both spatial resolution and revisit frequency. However, even PS's latest 8-channel satellite SuperDove lacks short-wave infrared spectral bands required for soil variation as well as urban development measures, such as the Normalized Difference Built-up Index (Zha et al., 2003), widely deployed to monitor urban change. Moreover, PS assets have been deemed as lacking in some aspects of data quality (Frazier and Hemingway, 2021). Given high levels of humidity in the tropics, satellite networks with high revisit frequencies can offer the best chance for cloud-free views. The high revisit frequency and high spatial resolution afforded by the PS satellite network enable previously unavailable opportunities for the analysis of remote sensing data in the tropics. For example, the SVM classification operating on PS assets (table 1) can detect the famous Balinese rice paddies robustly while they are almost imperceptible in the Landsat based results. Yet even imagery from PS requires additional ground-level information in order to disambiguate complex land cover conditions. The high growth and re-growth rates in the tropics as well as dynamics of Bali's informal economy require additional location-specific and context-sensitive knowledge in order to determine the actual conditions on the ground as described in related recent work (Böhlen, Iryadi and Liu, 2022). Moreover, PS assets come at a financial cost that can be unsustainable for resource-constrained emerging economies. Because one size does not fit all, we propose an approach that combines advantages found across the discussed image assets. We propose an approach that uses freely available (Sentinel2) sources to regularly monitor an area of interest, and then switches to the highest resolution asset only if a condition of concern or interest has been detected and not adequately understood. Not unlike the tip and cue concept in which one monitors an area of interest with one sensor and then 'tips' another complementary sensor platform to acquire another image over the same area, we tip and cue in this case based on economic constraints. We have implemented this approach in an open source software system based on ORFEO and GDAL libraries, COCKTAIL, that allows one to perform this interpretation of tip and cue to automate the collection of Sentinel2 data, to perform simple band operations and data intensive classification tasks, and to then apply those same classification routines to PS data if deemed necessary ( table 1). We do not currently combine sensor data across the different satellite networks, and only use the freely available resource as a cue to move to the subsequent step. As COCKTAIL runs on Linux platforms, researchers can freely share code and analysis results remotely and asynchronously. This approach allows one to make productive use of the PS assets while minimizing costs; a fundamental requirement for resource constrained GIS research efforts typical of university as well as emerging economy contexts. [ABSTRACT FROM AUTHOR]

Background Cost effectiveness analysis (CEA) is a useful tool for allocation of constrained resources, yet CEA methodologies are rarely taught or implemented in developing nations. We aimed to assess exposure to, and interest in CEA, and identify barriers to implementation in Uganda. Methods A cross-sectional survey was carried out in Uganda using a newly developed self-administered questionnaire (via online and paper based approaches), targeting the main health care actors as identified by a previous study. Results Overall, there was a 68% response rate, with a 92% (69/75) response rate among the paper-based respondents compared to a 40% (26/65) rate with the online respondents. Seventy eight percent (74/95) of the respondents had no exposure to CEA. None of those with a master of medicine degree had any CEA exposure, and 80% of technical officers, who are directly involved in policy formulation, had no CEA exposure. Barriers to CEA identified by more than 50% of the participants were: lack of information technology (IT) infrastructure (hardware and software); lack of local experts in the field of CEA; lack of or limited local data; limited CEA training in schools; equity or ethical issues; and lack of training grants incorporating CEA. 93% reported a lot of interest in learning to conduct CEA, and over 95% felt CEA was important for clinical decision making and policy formulation. Conclusions Among health care actors in Uganda, there is very limited exposure to, but substantial interest in conducting CEA and including it in clinical decision making and health care policy formation. Capacity to undertake CEA needs to be built through incorporation into medical training and use of regional approaches. [ABSTRACT FROM AUTHOR]

Aiming at the deficiency of traditional data envelopment analysis (DEA) model, combined with the characteristics of high-tech industry R&D innovation process, the R&D innovation process is decomposed into technological development and economic transformation sub stage, considering "relationship of the sub stage" and "distribution structure of the initial input in the sub stage", this paper constructs two-stage network DEA model with constrained resources, so it realizes the improvement of high-tech industry R&D innovation efficiency measurement method, and this model is applied to empirically evaluate the efficiency of R&D innovation and sub stage for 17 Chinese high-tech industries, and get initial input configuration information. Compared with the existing researches, this model breaks through constraints which traditional DEA models ignore the high-tech industry R&D innovation system internal structure. The empirical results show that: From both the whole and two sub stage, the efficiency of 17 Chinese high-tech industries are low, which have considerable improvement room; according to efficiency matrix diagram, only ECPEM 3 subdivision industries belong to efficient intensive innovation, the most industries are characterized by double weak or a strong and a weak; according to the 5 kinds which 17 industries belong to, the overall R&D innovation efficiency of ECOEI is the highest, AAMI is the lowest. [ABSTRACT FROM AUTHOR]

This paper presents and describes the most relevant methods for the solution of the Resource Constrained Project Scheduling Problem, RCPSP. A critical review of the state of the art, based on the most signicant papers published in the academic literature on this topic is carried out. First, several exact methods of solution are shown and their main advantages and disadvantages are explained; the Branch and Bound methods, considered as the best exact algorithms for solving this problem, are described. Subsequently, several heuristic methods, especially those that have been implemented for sequencing problems, are considered. [ABSTRACT FROM AUTHOR]

This paper is motivated by, but not limited to, the task of scheduling jobs organized in workflows to a computational grid. Due to the dynamic nature of grid computing, more or less permanent replanning is required so that only very limited time is available to come up with a revised plan. To meet the requirements of both users and resource owners, a multi-objective optimization comprising execution time and costs is needed. This paper summarizes our work over the last six years in this field, and reports new results obtained by the combination of heuristics and evolutionary search in an adaptive Memetic Algorithm. We will show how different heuristics contribute to solving varying replanning scenarios and investigate the question of the maximum manageable work load for a grid of growing size starting with a load of 200 jobs and 20 resources up to 7000 jobs and 700 resources. Furthermore, the effect of four different local searchers incorporated into the evolutionary search is studied. We will also report briefly on approaches that failed within the short time frame given for planning. [ABSTRACT FROM AUTHOR]

Managing pressure ulcers remain a challenge and call for a multidisciplinary team approach to care. Even more daunting is the management of such patients in remote locations and in resource constrained situations. The management of pressure sores in a patient with progressive muscular atrophy has been discussed using resources that were locally available, accessible, and affordable. Community participation was encouraged. A holistic approach to care was adopted [ABSTRACT FROM AUTHOR]

Introduction: National medicines regulatory agencies are faced with challenges including limited resources and technical capacity, resulting in countries collaborating and sharing resources to improve efficiency of the review process to facilitate access to quality-assured medicines by their populations. One such collaboration is the Southern African Development Community (SADC) medicines registration collaborative initiative, ZaZiBoNa. Countries participate in the initiative by contributing to regulatory reviews and good manufacturing practices inspections. The aim of this study was to review and compare the registration processes of regulatory authorities of Mozambique, Namibia, South Africa, Tanzania, Zambia, and Zimbabwe to identify strategies for better alignment. Methods: A senior member of the division responsible for issuing marketing authorisations completed an established and validated questionnaire, which standardises the review process, allowing key milestones, activities and practices of the six regulatory authorities to be identified and compared. The completed questionnaires were validated by the heads of the respective agencies. Results: The six countries vary in population and in the size of their respective regulatory agency and the resources allocated to regulatory reviews. The review processes of the six agencies were similar; however, differences were noted in the milestones recorded; for example, two of the countries did not record the start of the scientific assessment. Additionally, decisions for marketing authorisation were made by an expert committee in four of the countries and by the head of the agency and the Minister of Health in two countries. All six agencies implemented the majority of good review practices; however, the need for improvement in the areas of transparency and communication and quality decision making practices was a common finding for all six countries. Conclusions: Participation in the ZaZiBoNa initiative has improved the way in which the six agencies perform regulatory reviews in their countries, highlighting the realisation of one of the key objectives of the initiative, which was building the expert capacity of member countries. Other agencies in the SADC region and beyond can use the results of this study to identify best practices, which in turn, could improve their regulatory performance., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Sithole, Mahlangu, Capote, Sitoie, Shifotoka, Gaeseb, Padayachee, Sehloho, Khea, Fimbo, Munkombwe, Mwale, Salek and Walker.)

Background: Decision-analytic models are routinely used as a framework for cost-effectiveness analyses of health care services and technologies; however, these models mostly ignore resource constraints. In this study, we use a discrete-event simulation model to inform a cost-effectiveness analysis of alternative options for the organization and delivery of clinical services in the ophthalmology department of a public hospital. The model is novel, given that it represents both disease outcomes and resource constraints in a routine clinical setting., Methods: A 5-year discrete-event simulation model representing glaucoma patient services at the Royal Adelaide Hospital (RAH) was implemented and calibrated to patient-level data. The data were sourced from routinely collected waiting and appointment lists, patient record data, and the published literature. Patient-level costs and quality-adjusted life years were estimated for a range of alternative scenarios, including combinations of alternate follow-up times, booking cycles, and treatment pathways., Results: The model shows that a) extending booking cycle length from 4 to 6 months, b) extending follow-up visit times by 2 to 3 months, and c) using laser in preference to medication are more cost-effective than current practice at the RAH eye clinic., Conclusions: The current simulation model provides a useful tool for informing improvements in the organization and delivery of glaucoma services at a local level (e.g., within a hospital), on the basis of expected effects on costs and health outcomes while accounting for current capacity constraints. Our model may be adapted to represent glaucoma services at other hospitals, whereas the general modeling approach could be applied to many other clinical service areas.