• The Journal of Asian Finance, Economics and Business
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• v.7 no.1
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• pp.111-121
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• 2020

The study measures the resource use efficiency of diesel based power generation in the Maldives and analyses factors which influence efficiency levels. Stochastic frontier analysis (SFA) technique is applied to data on 30 plants over two year period from 2016 to 2017. The study finds that technical efficiency scores varies from 0.44 to 0.98 across power plants. About 33 percent of the plants have scores below the mean technical efficiency score of 0.87. Empirical results indicate ownership and use of solar photovoltaic (PV) have an influence on improving efficiency levels. Privately owned power plants in resort islands obtained higher technical efficiency scores compared to public and community owned power plants. This is a significant finding as the first study that used power plants in tourist sector in a comparative study. Size of the power plants was not found significant, but relatively small installed capacities can also be efficient. This finding is important because in many inhabited islands installed capacities remain oversized compared to the load. The benchmarking exercise offers model power plants that are relatively efficient, for other power plants and policy makers in small islands to learn from.

• Journal of Institute of Control, Robotics and Systems
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• v.22 no.7
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• pp.536-542
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• 2016

To enhance tracking efficiency, a target-tracking filter with a resource management algorithm is required. One of the resource management algorithms chooses or evaluates the proper sampling time using cost functions which are related to the target tracking filter. We propose a resource management algorithm for bearing only tracking environments. Since the tracking performance depends on the system observability, the bearing-only tracking is one of challenging target-tracking fields. The proposed algorithm provides the adaptive sampling time using the variation rate of the error covariance matrix from the target-tracking filter. The simulation verifies the efficiency performance of the proposed algorithm.

• Journal of Satellite, Information and Communications
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• v.10 no.4
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• pp.32-38
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• 2015

Next generation military satellite communication systems have been developed for expanding capacity and survivability. As for expanding capacity, the communication systems require efficient techonology to use limited resource. So, next generation communication systems are expected to use MF-TDMA technology. MF-TDMA is the technology which has the advantages of FDMA and TDMA. By using MF-TDMA, communication systems can use limited resource efficiently, and the performance of resource allocation depends on the allocation scheme. In this paper, we propose efficient allocation scheme for next generation military satellite communication systems. Also, we compare and analze performances such as Total Resource Efficient, Reject Ratio, Computational Time, PSD distribution with existing allocation schemes.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38A no.10
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• pp.898-907
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• 2013

For D2D communications underlaying cellular networks, it is essential to consider the mutual interference between the existing cellular communications and D2D communications as well as the spectral efficiency, as they need to share the same frequency. Accordingly, a resource allocation scheme should be designed in such a way that minimizes the mutual interference and maximizes the spectrum utilization efficiency at the same time. In this paper, we propose a resource allocation scheme based on cooperation of the base station and D2D terminals. Specifically, a D2D terminal senses the cellular spectrum to recognize the interference condition, chooses the best cellular resource, and reports the information to the base station. The base station allocates D2D resource such that the corresponding D2D link and cellular link share the same resource. The performance of the proposed resource allocation scheme is ated through compu under 3GPP LTE-Advanced scenarios.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.1
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• pp.238-256
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• 2016

Modern web services have been broadly deployed on the Internet. Most of these services use multi-tier architecture for flexible scaling and software reusability. However, managing the performance of multi-tier web services under dynamic and unpredictable workload, and different resource demands in each tier is a critical problem for a service provider. When offering quality of service assurance with least resource usage costs, web service providers should adopt self-adaptive resource provisioning in each tier. Recently, a number of rule- and model-based approaches have been designed for dynamic resource management in virtualized data centers. This survey investigates the challenges of resource provisioning and provides a competing assessment on the existing approaches. After the evaluation of their benefits and drawbacks, the new research direction to improve the efficiency of resource management and recommendations are introduced.

• The KIPS Transactions:PartC
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• v.12C no.6 s.102
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• pp.891-900
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• 2005

This paper studies network recovery methods for WDM optical mesh networks, concentrating on improving spare resource utilization. The resource efficiency can be obtained by sharing spare resources needed for network recovery. To improve the sharability of spare resources in WDM networks, methods to share backup paths us well as spare capacity should be studied. The proposed method in this paper uses multiple ring-covers and this method provides fast and simple recovery operation by exploiting the characteristics of logical ring topology, and also provides efficient resource utilization by using multiple distributed backup paths to improve the sharability of overall spare resources in the networks. This method can provide layered reliability to network service by enabling hierarchical robustness against multiple failures. The performance results show that the proposed method provide improved resource efficiency for single failure and enhanced robustness for multiple failures.

• The Journal of Fisheries Business Administration
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• v.12 no.2
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• pp.73-100
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• 1981

Fisheries resources, due to their intrinsic biological -density dependent, and socio- economic -common property nature, might yield the sustained benefits to the society involved, depending on the degree to which the social management scheme, pursuing the optimum yield from each of them, is framed. And besides, the success or failure of the management on them would, with no doubt, lead parallelly to the direction on scientific study of "Natural Resource Economics." Thus the objectives of the management, to ensue the best use of these society's resource, should underlie the technical, economic, ana social efficiency all together to meet the maximization of society's benefits from yields, taking account of managerial efficiency. And those multiple conflicts need communications between biologists, social scientists, and managers given tile mandate, tobe coordinated to arrive at a unique value weighed, through the well-ordered system approach and resulting timely decision-making which accommodates dynamical fisheries aspects and varying social purposes. purposes.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.16 no.10
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• pp.3256-3274
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• 2022

With the rapid development of information and communications technology, the construction of efficient, reliable, and safe Internet of Things (IoT) is an inevitable trend in order to meet high-quality demands for the forthcoming 6G communications. In this paper, we study a secure intelligent reflecting surface (IRS)-assisted IoT system where malicious eavesdropper trying to sniff out the desired information from the transmission links between the IRS and legitimate IoT devices. We discuss the system overall performance and propose a hybrid resource allocation scheme for maximizing the secrecy capacity and secrecy energy efficiency. In order to achieve the trade-off between transmission reliability, communication security, and energy efficiency, we develop a quantum-inspired marine predator algorithm (QMPA) for realizing rational configuration of system resources and prevent from eavesdropping. Simulation results demonstrate the superiority of the QMPA over other strategies. It is also indicated that proper IRS deployment and power allocation are beneficial for the enhancement of system overall capacity.

• Environmental and Resource Economics Review
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• v.17 no.1
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• pp.23-49
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• 2008

In this paper, we estimate whether changes in the economic environment a firm operates in affects technical efficiency. Since efficiency gains can manifest themselves in a variety of ways, we estimate for efficiency gains on annual generating plants input demand for expenses and fuel use. We find that generating plants reduced their workers and costs respectively by 6.8% in 1999 and 37.9% in 2001. However, they didn't show any systematic caloric consumption changes facing various economic environmental shocks. These results suggest that restructuring brought efficiency gains by replacing regulated monopoly with a more competitive firms in the context of the Korean electricity market.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.6
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• pp.2873-2892
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• 2019

Reducing the interference to the licensed mobile users and obtaining the energy efficiency are key issues in cognitive heterogeneous networks. A corresponding rate loss constraint is proposed to be used for the sensing-based spectrum sharing (SBSS) model in cognitive heterogeneous networks in this paper. Resource allocation optimization strategy is designed for the maximum energy efficiency under the proposed interference constraint together with average transmission power constraint. An efficiency algorithm is studied to maximize energy efficiency due to the nonconvex optimal problem. Furthermore, the relationship between the proposed protection criterion and the conventional interference constraint strategy under imperfect sensing condition for the SBSS model is also investigated, and we found that the conventional interference threshold can be regarded as the upper bound of the maximum rate loss that the primary user could tolerate. Simulation results have shown the effectiveness of the proposed protection criterion overcome the conventional interference power constraint.