• Journal of Korean Institute of Industrial Engineers
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• v.34 no.2
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• pp.216-222
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• 2008

The determination of spectrum charges for the operators is a main issue to efficiently manage the limited radio spectrum resources. In this paper, we propose a model to compute the optimal charges for radio spectrum usage. The objective is to determine that will maximize the spectrum charges, and decision variables of ratios for actual or estimated revenues are considered. The spectrum charges are maximized under satisfying the least profit for operators based on Log-Linear demand function. The parameters of actual sales and minimum profit of operators are analyzed to make an efficient management for radio spectrum. The results show that the spectrum charges increase as the actual sales increase, but it decrease as the required minimum profit of operator increases. It is also observed that the government should increase the ratio for estimated sales if anticipating the poor market in the future, otherwise they should increase the ratio for actual sales to maximize the spectrum charges.

• Journal of Forest and Environmental Science
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• v.36 no.1
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• pp.7-16
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• 2020

Tree size distribution modelling is an integral part of forest management. Most distribution yield systems rely on some flexible probability models. In this study, a simple finite mixture of two components two-parameter Weibull distribution was compared with complex four-parameter distributions in terms of their fitness to predict tree size distribution of teak (Tectona grandis Linn f) plantations. Also, a system of equation was developed using Seemingly Unrelated Regression wherein the size distributions of the stand were predicted. Generalized beta, Johnson's SB, Logit-Logistic and generalized Weibull distributions were the four-parameter distributions considered. The Kolmogorov-Smirnov test and negative log-likelihood value were used to assess the distributions. The results show that the simple finite mixture outperformed the four-parameter distributions especially in stands that are bimodal and heavily skewed. Twelve models were developed in the system of equation-one for predicting mean diameter, seven for predicting percentiles and four for predicting the parameters of the finite mixture distribution. Predictions from the system of equation are reasonable and compare well with observed distributions of the stand. This simplified mixture would allow for wider application in distribution modelling and can also be integrated as component model in stand density management diagram.

• Convergence Security Journal
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• v.2 no.2
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• pp.109-121
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• 2002

As the development of information technology and thus the growth of security incidents, there has been increasing demand on developing a system for centralized security management, also known as Enterprise Security Management(ESM), uniting functions of various security systems such as firewall, intrusion detection system, virtual private network and so on. Unfortunately, however, developers have been suffering with a lack of related standard. Although ISTF recently announced firewall system and intrusion detection system log format, it still needs for truly efficient ESM further development of the related standard including event and control messaging. This paper analyses ISTF standard and further suggests an additional event and control messaging standard for firewall and intrusion detection systems. It is expected that this effort would be helpful for the development of ESM and further related standard.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.10a
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• pp.578-580
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• 2013

In order to provide the virtual desktop service for computer programing training, User group to use the service should be created for each subject. And the management program to manage development tools, disk images, user account information, log data is required. In this study, we implemented the web-based operation management system to manage the virtual desktop service for computer programming training. We can provide rapid provisioning for the virtual desktop service by using the implemented system.

• Journal of Integrative Natural Science
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• v.11 no.1
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• pp.44-50
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• 2018

In this paper, we propose a context-aware power management (CPM) scheme using beacons to reduce the power consumption of personal computers (PCs). In the proposed CPM scheme, the PC, smartphone, control server, and Internet of Things (IoT) device are necessary. PC users first log in the control server using their smartphones and select PCs to turn on. Then, the selected PCs automatically go into three different modes, i.e., sleep, shutdown, and standby power off modes, in order when the PC users leave the PCs without turning off them. Further, we develop a testbed with the proposed CPM scheme using the Arduino with Bluetooth low energy (BLE) and relay modules. Finally, it is shown that the proposed CPM scheme outperforms the conventional scheme in terms of the power consumption.

• International Journal of Highway Engineering
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• v.15 no.1
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• pp.155-161
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• 2013

PURPOSES: This study is to develop a road traffic sign recognition and automatic positioning for road facility management. METHODS: In this study, we installed the GPS, IMU, DMI, camera, laser sensor on the van and surveyed the car position, fore-sight image, point cloud of traffic signs. To insert automatic position of traffic sign, the automatic traffic sign recognition S/W developed and it can log the traffic sign type and approximate position, this study suggests a methodology to transform the laser point-cloud to the map coordinate system with the 3D axis rotation algorithm. RESULTS: Result show that on a clear day, traffic sign recognition ratio is 92.98%, and on cloudy day recognition ratio is 80.58%. To insert exact traffic sign position. This study examined the point difference with the road surveying results. The result RMSE is 0.227m and average is 1.51m which is the GPS positioning error. Including these error we can insert the traffic sign position within 1.51m CONCLUSIONS: As a result of this study, we can automatically survey the traffic sign type, position data of the traffic sign position error and analysis the road safety, speed limit consistency, which can be used in traffic sign DB.

• Journal of Internet Computing and Services
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• v.20 no.2
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• pp.101-108
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• 2019

Workflow management systems (WfMSs) automate and manage workflows, which are implementations of organizational processes operated in process-centric organizations. In this paper, wepropose an algorithm to discover temporal work transference networks from workflow execution logs. The temporal work transference network is a special type of enterprise social networks that consists of workflow performers, and relationships among them that are formed by work transferences between performers who are responsible in performing precedent and succeeding activities in a workflow process. In terms of analysis, the temporal work transference network is an analytical property that has significant value to be analyzed to discover organizational knowledge for human resource management and related decision-making steps for process-centric organizations. Also, the beginning point of implementinga human-centered workflow intelligence framework dealing with work transference networks is to develop an algorithm for discovering temporal work transference cases on workflow execution logs. To this end, we first formalize a concept of temporal work transference network, and next, we present a discovery algorithm which is for the construction of temporal work transference network from workflow execution logs. Then, as a verification of the proposed algorithm, we apply the algorithm to an XES-formatted log dataset that was released by the process mining research group and finally summarize the discovery result.

• Korean Journal of Food Science and Technology
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• v.43 no.1
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• pp.39-44
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• 2011

This study was carried out to examine microbiological contamination of ready-to-eat products and to propose a draft-standard and specifications according to food types. RTE foods were classified into 6 groups including fish products, meat products, breads, rices, salads, and fresh cut foods. The prevalence rates of pathogens detected from all samples were compared among food categories. The pH ranges for all RTE samples were between 3.8 and 7.3. Total aerobic cell counts ranged from 2 to 6 log CFU/g. Bread, rice and fresh-cut foods showed significantly higher counts, which ranged above 4.0 log CFU/g among the samples. Two kinds of rice were above the level of the KFDA Food Code standard for Eschrichia coli. The prevalence rate of E. coli in the rice was 6.7%. For Staphylococcus aureus, one fish product and one bread-product had levels above 2 log CFU/g. Bacillus cereus counts for all samples were below the level of 3 log CFU/g. Listeria monocytogenes was not detected in the samples. Therefore, these data suggest that the primary microbial hazard factors for ready-to-eat foods and risk assessments should focus on E. coli, S. aureus, and B. cereus.

• Journal of agriculture & life science
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• v.45 no.6
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• pp.163-173
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• 2011

The objective of this study was to determine microbiological risk factors in hot pepper farms for the application of good agricultural practices (GAP). Samples were collected from cultivation environments and utensils, plants, workers, and air at 3 hot pepper farms located in Cheongsong, Korea and were tested to detect sanitary indications [aerobic plate bacteria (APC), coliform, and Escherichia coli], foodborne pathogens, and fungi. APC, coliform, and fungi were detected at the levels of 0.7~6.2, 0.2~4.7, and 0.4~4.3 log CFU, respectively, in the three farms. Four (4.4%; l leaf, l irrigation water, and 2 soil) of 90 samples collected were revealed to be E. coli positives. For foodborne pathogens, Staphylococcus aureus was only detected at $1.0log\;CFU/100cm^2$ in the worker's cloth of B farm, and Bacillus cereus was detected at the levels 1.0~2.5 log CFU in the cultivation environments and utensils and worker of B and C farms. However, other pathogens were not detected. The results demonstrated potential microbiological risks for hot pepper cultivated in the farms. Therefore, a management system to minimize the microbial risk such as GAP is required to ensure the safety of hot pepper.

• The Journal of Korean Association of Computer Education
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• v.10 no.4
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• pp.93-102
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• 2007

The present study is to investigate the elements of e-learning strategies affecting the levels of participation, achievement and satisfaction for learners who participated in the university blended learning environment. For this, 58 subjects were recruited who participated in the blended learning class at K university. E-learning strategies, achievement and satisfaction levels were measured for data collection, and the level of participation was measured by analyzing the LMS log-in database. For data analysis, first, means and standard deviation were computed to find the level of e-learning strategies of the subjects. Second, linear regression analysis was conducted to find the e-learning strategies that could estimate the levels of achievement, participation and satisfaction. As a result, variables to estimate the achievement level included time management strategy and overload management strategy. Variables to estimate the participation level included self-directed strategy, time management strategy and overload management strategy. Finally, variables to estimate the satisfaction level included multiple discussion management strategy, asynchronous management strategy and sociality. Based on these estimated variables, the author suggested some ideas to increase the educational effectiveness.