management problem
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Ganna Samchuk ◽  
Denis Kopytkov ◽  
Alexander Rossolov

The article deals with the problem of estimating the rational number and utilization rate of the vehicles' fleet. According to the analysis results of the state-of-the-art literature it has been revealed that the issue of substantiating the rational fleet size and the rate of its utilization were not fully solved. The purpose of the study was to increase the efficiency of servicing transportation orders by determining the required number of vehicles. The goal of the research was the influence of the transportation process parameters on the truck utilization rate. Originating from the probabilistic nature of the transportation process, it has been proposed to use the AnyLogic software product to develop a simulation model for vehicle orders' servicing. From the processing of the experimental results by the regression analysis methods, it has been found that the dependence of changes in the vehicle utilization rate is of a linear form.

2022 ◽  
Vol 138 ◽  
pp. 105568
Leonie M. Johannsmann ◽  
Emily M. Craparo ◽  
Thor L. Dieken ◽  
Armin R. Fügenschuh ◽  
Björn O. Seitner

SinkrOn ◽  
2022 ◽  
Vol 7 (1) ◽  
pp. 147-154
Deuis Nur Astrida ◽  
Agung Restu Saputra ◽  
Akhmad Ikhza Assaufi

The use of computer networks in an agency aims to facilitate communication and data transfer between devices. The network that can be applied can be using wireless media or LAN cable. At SMP XYZ, most of the computers still use wireless networks. Based on the findings in the field, it was found that there was no user management problem. Therefore, an analysis and audit of the network security system is needed to ensure that the network security system at SMP XYZ is safe and running well. In conducting this analysis, a tool is needed which will be used as a benchmark to determine the security of the wireless network. The tools used are Penetration Testing Execution Standard (PTES) which is one of the tools to become a standard in analyzing or auditing network security systems in a company in this case, namely analyzing and auditing wireless network security systems. After conducting an analysis based on these tools, there are still many security holes in the XYZ wireless SMP that allow outsiders to illegally access and obtain vulnerabilities in terms of WPA2 cracking, DoS, wireless router password cracking, and access point isolation so that it can be said that network security at SMP XYZ is still not safe

2022 ◽  
David Simchi-Levi ◽  
Rui Sun ◽  
Huanan Zhang

We study in this paper a revenue-management problem with add-on discounts. The problem is motivated by the practice in the video game industry by which a retailer offers discounts on selected supportive products (e.g., video games) to customers who have also purchased the core products (e.g., video game consoles). We formulate this problem as an optimization problem to determine the prices of different products and the selection of products for add-on discounts. In the base model, we focus on an independent demand structure. To overcome the computational challenge of this optimization problem, we propose an efficient fully polynomial-time approximation scheme (FPTAS) algorithm that solves the problem approximately to any desired accuracy. Moreover, we consider the problem in the setting in which the retailer has no prior knowledge of the demand functions of different products. To solve this joint learning and optimization problem, we propose an upper confidence bound–based learning algorithm that uses the FPTAS optimization algorithm as a subroutine. We show that our learning algorithm can converge to the optimal algorithm that has access to the true demand functions, and the convergence rate is tight up to a certain logarithmic term. We further show that these results for the independent demand model can be extended to multinomial logit choice models. In addition, we conduct numerical experiments with the real-world transaction data we collect from a popular video gaming brand’s online store on The experiment results illustrate our learning algorithm’s robust performance and fast convergence in various scenarios. We also compare our algorithm with the optimal policy that does not use any add-on discount. The comparison results show the advantages of using the add-on discount strategy in practice. This paper was accepted by J. George Shanthikumar, big data analytics.

2022 ◽  
Vol 51 (2) ◽  
pp. 345-364
Heni Nuraeni Zaenudin ◽  
Rika Sartika ◽  
Muhammad Endriski Agraenzopati Haryanegara

This study is aimed at measuring the effectiveness of policy communication in promoting #KangPisMan program among university students. #KangPisMan is a top priority program of Bandung Municipal Government to tackle waste management problem. In this sense, the problem of plastic waste has become a global concern about environment, therefore it is a hope that, by promoting #KangPisMan, a new lifestyle will make people more aware of environmental sustainability. The program was established in 2018, so it is necessary to measure the effectiveness of its communicating strategy. In terms of public communication, the realization of promoting the program should be measured based on its optimal value. The present study seeks to analyse the effectiveness of communication strategy by employing 7C concepts as introduced. The questionnaire was distributed to 300 respondents (based on purposive sampling) which were registered as students of Faculty of Social Sciences Education, Universitas Pendidikan Indonesia. Validity of the questionnaire is measured by corrected item-total correlation. The analysis shows that communication strategy in promoting #KangPisMan was relatively effective by considering the lowest scores of continuity and consistency. It shows that the aspect of consistency in promoting the program should be enhanced. Meanwhile, the aspect of credibility had the highest value. Therefore, it is a big capital to promote the program through the role model as reflected by the team. In general, all respondents were satisfied of the communication strategy in promoting the program. However, the effectiveness is still potential to be developed in the upcoming time.

2021 ◽  
Vol 2021 ◽  
pp. 1-17
Yuhao Yang ◽  
Xiujie Huang ◽  
Jinyu Hu

Internet of vehicles (IoV), a novel technology, holds paramount importance within the transportation domain due to its ability to increase traffic efficiency and safety. Information privacy is of vital importance in IoV when sharing information among vehicles. However, due to the openness of the communication network, information sharing is vulnerable to potential attacks, such as impersonation, modification, side-channel and replay attacks, and so on. In order to resolve the aforementioned problem, we present a conditional privacy-preserving batch authentication (CPPBA) scheme based on elliptic curve cryptography (ECC). The proposed scheme avoids the certificate management problem, conducing to efficiency improvement. When a message is transmitted by a vehicle, its pseudo identity rather than the real identity is also broadcasted along with the shared message, which protects the privacy of the vehicle’s identity. But this privacy is conditional because TA and only the TA can reveal the real identity of the vehicle by tracing. The proposed scheme is batch verifiable, which reduces the computation costs. In addition, our scheme does not involve bilinear pairing operations and does not use the map-to-point hash function, thus making the verification process more effective. An exhaustive efficiency comparison has been carried to show that the proposed CPPBA scheme has lower computation, communication, and storage overheads than the state-of-the-art ones. A relatively comprehensive security analysis has also been carried, which not only shows that the signature design in the CPPBA scheme is unforgeable under the random oracle model but also illustrates that the CPPBA scheme is resistant to various potential attacks. The security is also verified by a popular automated simulation tool, that is, AVISPA.

Sensors ◽  
2021 ◽  
Vol 22 (1) ◽  
pp. 100
Chiu-Han Hsiao ◽  
Yean-Fu Wen ◽  
Frank Yeong-Sung Lin ◽  
Yu-Fang Chen ◽  
Yennun Huang ◽  

Network slicing is a promising technology that network operators can deploy the services by slices with heterogeneous quality of service (QoS) requirements. However, an orchestrator for network operation with efficient slice resource provisioning algorithms is essential. This work stands on Internet service provider (ISP) to design an orchestrator analyzing the critical influencing factors, namely access control, scheduling, and resource migration, to systematically evolve a sustainable network. The scalability and flexibility of resources are jointly considered. The resource management problem is formulated as a mixed-integer programming (MIP) problem. A solution approach based on Lagrangian relaxation (LR) is proposed for the orchestrator to make decisions to satisfy the high QoS applications. It can investigate the resources required for access control within a cost-efficient resource pool and consider allocating or migrating resources efficiently in each network slice. For high system utilization, the proposed mechanisms are modeled in a pay-as-you-go manner. Furthermore, the experiment results show that the proposed strategies perform the near-optimal system revenue to meet the QoS requirement by making decisions.

PLoS ONE ◽  
2021 ◽  
Vol 16 (12) ◽  
pp. e0260673
Ahmad Sher ◽  
Muhammad Yasir Arfat ◽  
Sami Ul-Allah ◽  
Abdul Sattar ◽  
Muhammad Ijaz ◽  

Sunflower production is significantly lower in arid and semi-arid regions due to various crop management problem. Conservation of tillage provides the most excellent opportunity to reduce degradation of soil reserves and increase soil productivity. The main objective of this study was to investigate the combined effects of conservation tillage and drought stress on growth and productivity of different sunflower hybrids. Experimental treatments included two sunflower hybrids (‘NK-Senji’ and ‘S-278’), two drought stress treatments (i.e., well-watered and drought stress at flowering and grain filling stages) and three tillage practices (i.e., conservation, minimum and deep tillage). The results indicated that morphological and physiological parameters, and yield-related traits were significantly (P≤0.05) affected by all individual factors; however, their interactive effects were non-significant. Among sunflower hybrids, ‘NK-Senji’ performed better for morphological, physiological, and yield-related traits than ‘S-278’. Similarly, conservation tillage observed better traits compared to the rest of the tillage practices included in the study. Nonetheless, conservation tillage improved growth and yield-related traits of hybrid ‘NK-Senji’ under drought stress. Hence, it is concluded that conservation tillage can improve the productivity of sunflower under low moisture availability. Therefore, conservation tillage could be suggested in the areas of lower water ability to improve sunflower production. Nonetheless, sunflower hybrids or varieties need thorough testing for their adaptability to conservation tillage and low moisture availability before making recommendations.

2021 ◽  
Vol 4 (1) ◽  
pp. 32
Alvi Jauharotus Syukriya ◽  
Lensa Rosdiana Safitri

Islam has comprehensive rule that regulate in all aspects of human life, including evireonmental issues. One fact of global problems related to environment is waste management problem. Zero waste is waste management system which it could be a holistic solution due to waste issue. This study aim to analyse the zero waste concept within Islamic-science prespective on municipal waste reduction as a solution to prevent environmental damage. This study use literature reviews method that focuse on waste management programs in Surabaya City which have been stated on a national and international scale. The results of this study show implementation of waste management programs In Surabaya City such as the depletion of disposable plastic usage, the existence of waste bank units, until the presence of a solid waste power plant infrastructure. However, the program implementation has not been able to decrease the number of resource in Surabaya landfill. It is because of poorly coordination between government and society, and the lack of environmental awareness about the harm of waste resource to environmental health. Thus, the existence of zero waste concept combined with Islamic-science prespective could lead direction movement to appreciate the importance of proper and correct waste management. Based on these results, it conclude that waste management with zero waste concept considered to become a new lifestyle in waste management namely Islamic lifestyle, because it is in line with Islamic law. Moreover, this new lifestyle could be implemented in all communities regarding to the nature is a gift form Allah SWT and humans have a command to protect it.

2021 ◽  
Vol 13 (24) ◽  
pp. 13907
Xin Wang ◽  
Jason Atkin ◽  
Najmeh Bazmohammadi ◽  
Serhiy Bozhko ◽  
Josep M. Guerrero

Safety issues related to the electrification of more electric aircraft (MEA) need to be addressed because of the increasing complexity of aircraft electrical power systems and the growing number of safety-critical sub-systems that need to be powered. Managing the energy storage systems and the flexibility in the load-side plays an important role in preserving the system’s safety when facing an energy shortage. This paper presents a system-level centralized operation management strategy based on model predictive control (MPC) for MEA to schedule battery systems and exploit flexibility in the demand-side while satisfying time-varying operational requirements. The proposed online control strategy aims to maintain energy storage (ES) and prolong the battery life cycle, while minimizing load shedding, with fewer switching activities to improve devices lifetime and to avoid unnecessary transients. Using a mixed-integer linear programming (MILP) formulation, different objective functions are proposed to realize the control targets, with soft constraints improving the feasibility of the model. In addition, an evaluation framework is proposed to analyze the effects of various objective functions and the prediction horizon on system performance, which provides the designers and users of MEA and other complex systems with new insights into operation management problem formulation.

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