Cost Control Research Articles

Non‐fragile reliable guaranteed cost control and L2‐gain analysis for saturated switched nonlinear systems

AbstractFor the nonlinear continuous‐time saturated switched system, this article investigates the problem of non‐fragile reliable guaranteed cost control of the system. Due to the simultaneous occurrence of controller perturbation, actuator saturation and actuator failure, when designing the cost function, this article considers three scenarios affecting the system performance, controller perturbation, actuator saturation and actuator failure, simultaneously in the cost function, which has not been investigated in the existing literature. For nonlinear switched systems, we derive some sufficient conditions to satisfy simultaneously the stabilization of non‐fragile reliable guaranteed cost control and the performance index. In order to ensure the exponential stabilization of the nonlinear switched systems and minimize the upper bound of cost function, a switching law and the non‐fragile reliable guaranteed cost state feedback controllers are designed by using the minimum dwell‐time method. Furthermore, by solving optimization problems with linear matrix inequality constraints, the minimum upper bound of the cost function and the performance of the system are determined. At the end of the article, we give a numerical example to verify the effectiveness of the proposed approach.

A topological derivative-based algorithm to solve optimal control problems with $L^0(\Omega)$ control cost

In this paper, we consider optimization problems with $L^0$-cost of the controls. Here, we take the support of the control as independent optimization variable. Topological derivatives of the corresponding value function with respect to variations of the support are derived. These topological derivatives are used in a novel gradient descent algorithm with Armijo line-search. Under suitable assumptions, the algorithm produces a minimizing sequence.

Research on Lithium Battery Recycling and Utilization

With the rapid development of new energy, lithium batteries, as one of the key technologies in the field of energy storage, play an important role. However, with the widespread application of lithium batteries, the problem of their disposal has become increasingly prominent, which not only affects the environment but also wastes precious resources. This article analyzes the domestic new energy lithium battery market situation and finds that domestic new energy is developing rapidly and the lithium battery market has huge potential. In terms of lithium battery recycling and utilization, comparison shows that foreign lithium battery recycling technology is relatively mature, but there are certain challenges in adapting to domestic actual conditions and cost control. Although there are some advanced recycling technologies in China, the overall level still needs to be improved.

Exploring the semi-supervised learning for weed detection in wheat

Computer vision-based precision spraying of herbicides presents a promising avenue for reducing herbicide input and weed control costs. Nonetheless, weed detection in wheat (Triticum aestivum L.) remains challenging. Developing an effective and reliable neural network for weed detection requires substantial labeled data for training. However, labeling data is time-consuming and labor-intensive. To address this challenge, the present study introduces semi-supervised learning (SSL) into the domain of weed detection in wheat. The performance of four SSL methods was thoroughly evaluated and compared with that of a fully supervised learning (FSL) method on a dataset with a limited amount of labeled images. Experimental results showed that the Fixmatch method, an SSL approach, outperformed the FSL method, exhibiting significantly higher accuracy (ACC) with a limited number of labeled images. The ACC of Fixmatch was 85.4%, which was 7.3% higher than the FSL method. In further analysis, the performance of models trained on a dataset containing 100, 200, 300, 400, 500, or 1000 labeled images per class was tested. Compared with FSL, SSL achieved the greatest improvement when the number of labels was 200. At the same time, Fixmatch achieved satisfactory performance, ACC, recall, and precision reached 94.8%, 94.8%, and 95.2%, respectively, and the F1 score was 95%. In summary, these results suggest that using the SSL method could yield a high-performing model when training with a limited number of labeled images, requiring less training costs and lower demands on manpower.

Efisiensi Perolehan Pendapatan Antara Beban Yang Dikeluarkan Dengan Pendapatan Terhadap Keuntungan Usaha Menggunakan Metode Target Costing (Studi Pada Usaha Kuliner Jajanan Najla Di Purwakarta)

The magnitude of profit obtained is highly dependent on production cost efficiency, thus requiring special attention to achieve the company's target. Cost control must align with the company's objectives, including achieving maximum profit with minimal production costs. This study aims to analyze the relationship between expenses, income, and business profits in UMKM Jajanan Nazla, as well as identify key factors influencing the efficiency of revenue generation and expense expenditure. Based on the analysis of production costs, UMKM Jajanan Nazla faces a deficit in net profit due to the inability to cover production costs. Therefore, this research applies the target costing method to improve its profitability. The steps of implementing target costing involve determining market prices, calculating target profits, and identifying target production costs. By implementing value engineering, such as reducing packaging costs, labor costs, and even eliminating rental costs, UMKM successfully reduces production costs to meet the set target cost. As a result, production costs decreased from Rp. 7,880,000 to Rp. 5,240,000 per month, resulting in savings of Rp. 2,640,000. Thus, the initially deficit net profit increased to Rp. 1,510,000 per month after the application of target costing. In conclusion, it can be inferred that the target costing method is effective in improving the production cost efficiency of UMKM Jajanan Nazla, helping them strengthen their position in the competitive market.

Exploring tourism SMEs crisis management practices during Covid-19 at Boudha, Kathmandu

<p>The worldwide tourism industry alone expanded by 3.9% in 2018, contributing $8.8 trillion in sales and 319 million jobs to the global economy. The COVID-19 pandemic, which began to spread around the planet in 2020, had an impact on every aspect of life. Though many studies have explored COVID-19’s effects on tourism SMEs in Nepal, there’s a significant lack of research on their crisis management strategies during the pandemic. Thus, this study aims to measure the crisis management techniques used by small and medium-sized businesses (SMEs) in the Boudha Area during the COVID-19 epidemic. The study uses an explanatory research design to analyze a comprehensive understanding of how the Boudha Area’s SMEs in the tourism industry handled the crisis of SMEs in the Kathmandu Valley. Non-probability with convenient sampling is used for the study. Data is collected through 403 SMEs using a structural questionnaire, and data collection is done using Kobo Toolbox. Structural Equation Modeling (SEM) using Partial Least Squares (PLS) version 4.0 is adopted for data analysis. The result shows a significant relationship between cost control and expected assistance with crisis management, while marketing and organizational support have an insignificant relationship with crisis management. Similarly, during COVID-19, 90.82% of the businesses had closed their businesses, and 47.89% of SMEs had closed for 3 months. Additionally, 88.09% of SMEs faced losses during COVID-19, and to maintain the crisis 46.4% of SMEs used their income to handle crises during COVID-19, and 93.3% of SMEs reduced their expenses to manage the crisis.</p>

Analyzing the Impact of Economic Performance on the Interplay between Financial Management Strategies and Profitability in the Iraqi Context

Purpose - This study examines how economic performance affects financial management approaches and profitability in Iraq's construction business. This research examines how financial management strategies affect profitability and economic success. Design/Methodology/Approach—Construction project and site managers in Iraq were surveyed online for the study. Given the scope and magnitude of the research, this study's 85.3% response rate is impressive. In-depth statistical analysis was performed using Partial Least Squares Structural Equation Modelling (PLS-SEM), which examined economic performance, financial management, and profitability. Findings - The instance indicates that the lack of organization-wide integrated systems, common across enterprises, contributes to this problem. The major issue is that the organization's information systems strategy never expressly prioritizes KM-enabling schemes. Practical Implications—The study's conclusions have major practical ramifications. Iraqi enterprises should prioritize resource optimization, cost control, and strategic financial planning to improve economic performance. In addition, governments should promote building projects through incentives, subsidies, and tax policies that boost economic productivity and profitability. These policies are available here. Originality/Value—This study adds to the literature by stressing economic performance as a mediator between financial management methods and profitability in Iraq's construction sector. It examines the dynamics of this link in Iraq's building sector. With the new data, firms may improve financial performance by making informed judgments and using efficient financial management procedures.

Enhancing material toughness by introducing defects

Achieving high toughness is still very challenging in material science. Defect engineering offers novel avenues for making tough materials by finely adjusting microstructures, rather than relying on composite blends of different substances. However, how the introducing artificial defects affect the mechanical performances of materials and what factors influence the toughening effects of artificial defects remain poorly understood. In this study, we establish a theoretical framework that accounts for the stochastic distribution of initial defects in the materials and the controlled introduction of artificial defects. We find that the material becomes more brittle as the maximum initial defect increases. However, judiciously introducing artificial defects renders more regions in the materials to enter plastic deformation. Thus, materials can effectively absorb more energy during fracture, thereby enhancing their overall fracture toughness, no matter whether they are originally brittle or ductile. We further present the phase diagrams that elucidate the optimal conditions for improved material properties by introducing artificial defects. The predominance of defect-mediated toughening mechanisms broadens the materials design space and facilitates cost control and recycling.

Formulation a definition for the phenomenon of internal control of expenses for scientific (scientific and technical) enterprise activity

Scientific activity in Ukraine is a special kind of economic and social relations that forms the knowledge and innovative products. Currently, a significant part of scientific institutions are in a difficult financial situation due to the need of the state to finance the defense spending. This requires researchers to economically spend the money received. That is why, among the main tasks of scientific organizations there is a strict control of costs for scientific works, which requires the creation of a fundamentally new theoretical and methodological base within the framework of which the development of the existing conceptual apparatus and the discovery of the latest methodological approaches for cost control during research and development are envisaged. Determining the costs of creating a scientific product is carried out by a special direction of the internal activity of the enterprise — accounting for the costs of scientific activities in a specially formed unit or a separate employee, however, the work of this unit or employee should be monitored, for which it is advisable to form an appropriate functional management body — internal control costs for researches. The practice of accounting costs for the scientific activity and the regulatory framework for such accounting is formed on the basis of the rules established for production and commercial enterprises, there is a need for the development and implementation of new methodological and organizational solutions for streamlining the activities of specific accounting and regulatory bodies that have as their object the costs of scientific works. To start the processes of forming an orderly activity to control the costs of research in this article formulated the definition of the phenomenon of internal control of costs for scientific activities of the enterprise. This will make it possible to single out in the general management system of scientific organizations the employee (units) responsible for controlling the costs of scientific work, determine their goals and special functions, determine the composition of the labor intensity of control operations and develop cost control regulations.

Iodine- and nitrogen-CO-doped carbon flower materials for the anode electrode of lithium-ion batteries

As green anode materials with wide distribution, controllable cost, and diversified structure, carbon materials have received more attention. In this paper, iodine- and nitrogen-co-doped carbon flower materials were prepared. The flower-like structure of the material ensures the rapid diffusion of lithium ions, and the synergistic effect of iodine and nitrogen atoms improves the pore size distribution, the conductivity and the active sites of carbon materials realizing the high ion storage and the fast charge diffusion. As the anode material of lithium-ion batteries, the iodine- and nitrogen-co-doped carbon flower could have the capacitance of 410 mAh g[Formula: see text] at the current density of 0.1 A g[Formula: see text] after 150 cycles and 181 mAh g[Formula: see text] at the high current density of 2.0 A g[Formula: see text] after 1000 cycles. The results of electrochemical impedance spectroscopy, kinetics, and GITT show this material has fast charge transport kinetics and excellent rate performance.

Research on Influencing Factors of Cost Control of Centralized Photovoltaic Power Generation Project Based on DEMATEL-ISM

The high cost of centralized photovoltaic power generation projects is an important problem affecting industrial development, which needs to be solved urgently. It is particularly important to explore the influencing factors of cost control and the interaction between them. This paper takes a centralized photovoltaic power generation project as the research object, and determines the index system of influencing factors of cost control from the perspective of the life cycle. Secondly, the logical relationship between influencing factors is judged by the method of combining DEMATEL (decision-making trial and evaluation laboratory) and ISM (interpretive structural modelling). Finally, the multi-order recursive interpretation structure model is obtained, and the action mechanism between various factors is obtained. The results show that national policies and standards are the most profound influencing factors, and their cause degree reaches 2.155; the reason degree of market changes is the second, which is 1.586; bidding and contract management are the factors with the highest centrality, which is 7.120; and transmission and the storage of electricity and equipment repair and maintenance are the most direct factors affecting cost control. Finally, some suggestions are put forward for different types of influencing factors. The research results can better help photovoltaic power generation enterprises solve the problem of cost control.

Implementing high-value, cost-conscious care: experiences of Irish doctors and the role of education in facilitating this approach

BackgroundAdopting high-value, cost-conscious care (HVCCC) principles into medical education is growing in importance due to soaring global healthcare costs and the recognition that efficient care can enhance patient outcomes and control costs. Understanding the current opportunities and challenges doctors face concerning HVCCC in healthcare systems is crucial to tailor education to doctors’ needs. Hence, this study aimed to explore medical students, junior doctors, and senior doctors’ experiences with HVCCC, and to seek senior doctors’ viewpoints on how education can foster HVCCC in clinical environments.MethodsUsing a mixed-methods design, our study involved a cross-sectional survey using the Maastricht HVCCC-Attitude Questionnaire (MHAQ), with a subset of consultants engaging in semi-structured interviews. Descriptive analysis provided insights into both categorical and non-categorical variables, with differences examined across roles (students, interns, junior doctors, senior doctors) via Kruskal-Wallis tests, supplemented by two-group analyses using Mann-Whitney U testing. We correlated experience with MHAQ scores using Spearman’s rho, tested MHAQ’s internal consistency with Cronbach’s alpha, and employed thematic analysis for the qualitative data.ResultsWe received 416 responses to the survey, and 12 senior doctors participated in the semi-structured interviews. Overall, all groups demonstrated moderately positive attitudes towards HVCCC, with more experienced doctors exhibiting more favourable views, especially about integrating costs into daily practice. In the interviews, participants agreed on the importance of instilling HVCCC values during undergraduate teaching and supplementing it with a formal curriculum in postgraduate training. This, coupled with practical knowledge gained on-the-job, was seen as a beneficial strategy for training doctors.ConclusionsThis sample of medical students and hospital-based doctors display generally positive attitudes towards HVCCC, high-value care provision, and the integration of healthcare costs, suggesting receptiveness to future HVCCC training among students and doctors. Experience is a key factor in HVCCC, so early exposure to these concepts can potentially enhance practice within existing healthcare budgets.

A PMBOK-based construction cost management framework for BIM integration in construction projects

Cost overruns persist as a critical issue in construction projects. This study aims to explore how the integration of Building Information Modeling (BIM) can enhance project cost management processes aligned with the PMBOK framework, fostering improved construction cost control and management as well as decision-making. The study investigates the applicability of PMBoK cost management procedures within the context of BIM software and its various applications. A comprehensive BIM-cantered cost management framework is introduced to operationalize this synergy, encompassing planning, estimation, budgeting, monitoring, and control stages. This framework’s efficacy is validated through its application to an industrial facility, leveraging integrated BIM, scheduling, and cost tools. The findings revealed BIM’s benefits in visualization, clash detection, automated take-off, and 5D simulation, influencing informed decision-making during the project. However, these advantages coexist with certain limitations, including challenges in establishing bi-directional quantity-cost linkages, generating customizable reports, conducting risk-centric budgeting, and conducting in-depth subcontractor analyses. This research puts forth an applied BIM framework tailored to construction cost management and provides practical insights to guide adoption strategies and technology advancement needs. The study can assist industry practitioners and policymakers in re-evaluating cost management strategies concerning BIM capabilities.

Study on Cost Control of Construction Enterprises in the Context of the COVID-19 - A Case Study of China Construction

Study on Cost Control of Construction Enterprises in the Context of the COVID-19 - A Case Study of China Construction

Distributed optimal load frequency control for multi-area power systems with controllable loads

With the proliferation of distributed energy resources, power imbalance may fluctuate rapidly with a large amount, which may make the conventional frequency control scheme not respond fast to the fluctuation and operate in an economically inefficient manner. This paper proposes a distributed optimal load frequency control (DOLFC) scheme for multi-area power systems with controllable loads, which optimally dispatches generators and controllable loads to participate the frequency regulation with cost minimization. It can restore the nominal frequency and only needs local measurements and local communication for implementation. With the DOLFC, we prove that the closed-loop LFC system asymptotically converges to an equilibrium point which minimizes the control cost of generators and controllable loads, and the equilibrium point is unique if and only if the multi-area power network is a tree. Compared with the conventional LFC and economic LFC in literature, the proposed DOLFC has higher economic efficiency and better control performance. Finally, a four-area power system is employed to illustrate the effectiveness of the proposed scheme by numerical simulations.

CDT: Cross-interface Data Transfer scheme for bandwidth-efficient LoRa communications in energy harvesting multi-hop wireless networks

With the capability of generating sustainable energy by exploiting the ambient environment (e.g., light, heat, vibrations, etc.), the energy harvesting (EH) technology is increasingly used on low-power smart objects, forming self-powered green Internet of Things (IoTs). Despite targeting different application domains, many of these green IoT systems adopt the distributed network paradigm by forming energy harvesting multi-hop wireless networks (EH-MWNs). While distributed networks have good scalability during the deployment phase, they are often complex, inelastic to change, and costly to manage. To this end, LoRa, a promising long-range wireless technology, has been suggested for centralized single-hop network controls in EH-MWNs. However, the signal propagation of LoRa is severely affected by the surrounding environment (e.g., obstructions, terrains, etc.), which not only creates a significant difference in packet delivery rate (PDR) between nodes but also increases the bandwidth cost for network controls. To address this issue, we propose a Cross-interface Data Transfer (CDT) scheme, which leverages the ZigBee interfaces coexisting in EH-MWNs to transfer LoRa data traffic from the nodes with a lower PDR to the nodes with a higher PDR for bandwidth-efficient transmissions. By jointly determining the pairs of nodes performing data transfer and the data transfer rates between them, CDT can reduce the overall LoRa bandwidth consumption while ensuring continuous operation of the EH-MWN. A prototype system is implemented by integrating commercial off-the-shelf LoRa and ZigBee interfaces into an IoT platform. Extensive real-world experiments show that under a moderate data traffic input, the bandwidth consumption of CDT is 25.8% and 48.8% lower than the standard LoRaWAN and a state-of-the-art data transfer scheme, respectively. The average energy cost per node is kept as low as 2.29 mW at the same time. Moreover, CDT also shows its performance advantages in terms of PDR and sustainability.

Construction and Practice of Hospital Pharmacy Practice Teaching Mode under the Reform of DRG Payment Method

Objective: this research for DRGs payment reform, in order to build a new teaching mode of traditional pharmacy practice and DRGs payment reform background, the pharmaceutical interns add DRGs disease grouping and ICD disease coding teaching and DRGs disease grouping of pharmacoeconomics teaching, training more able to adapt to the medical reform of drug service personnel and hospital performance management and internal cost control training practical pharmaceutical service talents. Methods: Through the implementation of different internship programs, to make the effect evaluation. Results: Combining the traditional clinical pharmacy practice with the background of DRGs payment reform, the teaching of DRGs disease grouping, ICD disease coding teaching and pharmacoeconomics of DRGs disease grouping. Conclusion: In this study, the practice of Chinese pharmacy, prescription practice, clinical pharmacy and ward practice combined the teaching of DRGs disease grouping and ICD disease coding with the medical insurance department, which promoted the smooth implementation of DRGs and reflected the value of clinical pharmacists in ensuring effective, safe and economical drug use.

Dual effects of additional food supply and threshold control on the dynamics of a Leslie–Gower model with pest herd behavior

Bemisia tabaci is a major agricultural pest and recognized by the United Nations Food and Agriculture Organization (FAO) as the second largest pest in the world. This paper aims to study the management of Bemisia tabaci from theoretical aspects. Firstly, considering the omnivorous nature of natural enemy species and pest herd behavior, a Leslie–Gower type pest-natural enemy model with additional food supply and non-differentiable rational uptake function is put forward, and the effects of additional food supply and aggregation efficiency on the dynamical behavior of the system are analyzed. Secondly, for the slowness of pest control by natural enemy species, a threshold control strategy is adopted to prevent the spread of Bemisia tabaci by spraying a certain intensity of insecticides and releasing a certain number of natural enemies. The complex dynamics of the system induced by the threshold control are discussed such as the existence of predator-extinction periodic solution, the existence and stability of coexisting order-1 periodic solution. Thirdly, from the perspective of cost control, an optimization problem is constructed based on the existence of the order-1 periodic solution, and the optimal control threshold, control strength and control frequency are determined. At last, to illustrate the theoretical results more intuitively, the numerical simulations in MATLAB program are presented to illustrate the effectiveness and practical significance of the control measures. The results of this study provide a reference for the scientific and reasonable management of Bemisia tabaci and is helpful to realize the sustainable development of agricultural production.

Automatic Rainwater Quality Monitoring System Using Low-Cost Technology

Water quality monitoring serves diverse purposes, such as assessing water safety for drinking or agriculture. However, traditional methods are often time-consuming and costly. Additionally, assessing water quality on demand is not always feasible, and parameter variations are not consistently documented. With the advent of affordable equipment capable of efficient performance with minimal resources, remote monitoring sans physical access to the environment has become viable. This has led to reduced inspection and control costs. Understanding the applications, characteristics, and limitations of these devices is crucial for maximizing their benefits. Rainwater quality remains understudied in many areas, leaving its physical, chemical, and microbiological conditions unknown. These conditions are influenced by various atmospheric factors, including both human and natural activities. This research paper develops monitoring stations employing low-cost technology to assess rainwater quality in Morelia City. A prototype was developed based on low-cost technology implementation. Additionally, basic parameters measured include pH, total dissolved solids, turbidity, and temperature, utilizing an Arduino microcontroller for data processing. Data collected from these stations are transmitted via a Wi-Fi communication module to a web platform, enabling real-time visualization of measurements both spatially and temporally. Utilizing such a device offers several advantages compared to standard methods of assessing rainwater quality. It enables continuous measurements and provides a record of how rainwater quality is affected over time by human and natural activities.

How do time delays influence dynamics and controls of a generalized SEAIR model?

Given the critical role of time delays in epidemic modeling, this paper delves into the dynamics and finite-time optimal stabilization of a novel epidemic system characterized by such delays. Our findings reveal that time delays significantly influence both the system’s dynamics and the formulation of an optimal control strategy. Specifically, the system’s endemic equilibrium point remains locally asymptotically stable under mild conditions for small time delays. However, exceeding critical delay thresholds induces Hopf bifurcation. To closely regulate the system’s state towards the equilibrium point and minimize control costs, we propose an optimal control problem. We derive the explicit form of the optimal control strategy employing Pontryagin’s Maximum Principle. Finally, numerical simulations further confirm the theoretical results obtained in this paper.