• Tunnel and Underground Space
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• v.32 no.4
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• pp.254-271
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• 2022

The performance of truck haulage operations in an underground mine was evaluated using the time usage model and key performance indicators (KPIs) proposed by Global Mining Guidelines Group (GMG). An underground mine that mainly produces iron and titanium iron was selected as a study area, and truck haulage data were collected using Bluetooth beacons and tablet PCs. The collected data were analyzed to identify unit operations, activities, events, and required time of truck haulage operations, and time categories were classified based on the time usage model. The performance of the haulage operations was evaluated using nine indicators in terms of availability, utilization, and effectiveness. As a result, in terms of availability, uptime was 33.9%, physical availability was 95.7%, and mechanical availability was 94.9%. In the case of utilization, use of availability was 83.1%, asset utilization was 28.1%, and operating and effective utilization were 79.6% and 77.7%, respectively. Also, in terms of efficiency, operating efficiency was high at 97.6%, and production effectiveness was found to be 49%.

• Journal of the military operations research society of Korea
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• v.18 no.2
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• pp.23-43
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• 1992

A Stochastic simulation model for optimal design and evaluation of the integrated weapon systems under the consideration of the RAM (reliability, availability and maintainability) and life cycle cost (LCC) was developped. This model is supposed to satisfy a need regarding the methodology of optimaldesign and performance evaluation for both developpers and users of weapon systems.

• Journal of the Korean Institute of Gas
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• v.6 no.1 s.17
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• pp.66-73
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• 2002

In this study a new SIS evaluation method based on the reliability analysis has been developed. It evaluates the Safety Integrity Level (SIL) using the Fault Tree Analysis (FTA), and when the SIL falls short of the systems target level, through the reliability analysis and system retrofit, this method will satisfy the aimed SIL. A hazard evaluation was carried out on the 415V Diesel BUS to verify the SIL evaluation method based on the reliability analysis. The availability of the original 415V Diesel BUS was $99.40\%$, which comes under the category of SIL 2. After exchanging the diesel generator and the isolator switch using the developed evaluation method, the availability rose to $99.94\%$, SIL 3. By applying the method presented in this study, not only will it reduce the maintenance cost due to the prevention of accidents and reduction of loss, but also maximize the reliability of the system.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.9 no.13
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• pp.17-22
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• 1986

Man-machine system is an integrated total system which is linked by functions of man and machine, and the value of the system is determined by its compatability. And it is able to evaluate the system value on the aspects of utility, availability, and cost benefit. The authors previously represented the methodology of system utility using transfer functions, and this paper successively discusses the reliability of man-machine system. The reliability estimation and evaluation methodologies are briefly mentioned, and some examples are shown in this paper.

• Proceedings of the Korea Institutes of Information Security and Cryptology Conference
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• 1995.11a
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• pp.41-47
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• 1995

This research suggests a criterion, security quality, which is a unifying principle in computer network security that has the lack of a unifying principle. The security quality includes secrecy, integrity, recording, and availability among the factors that represent the security evaluation of the computer system. So, we defined the security quality, which is a basis for determining the security level, as the grand total of evaluation about each factor.

• Journal of Preventive Medicine and Public Health
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• v.41 no.2
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• pp.80-83
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• 2008

An economic evaluation is required in order to apply to the Health Insurance Review and Assessment Service (HIRA) for a listing in the national drug formulary. To assist companies in preparing the necessary documents, HIRA published guidelines for the economic evaluation of pharmaceuticals in 2006. The guidelines are composed of two parts: guidance and explanatory notes. Each guideline reflects the best practice which meets both the theoretical consensus within the academic community and local situations, like data availability. To enhance the transparency of evaluation, guidelines emphasize the reproducibility of data and analysis result. That is, all evaluation processes are required to be described in enough detail to be replicated by reviewers. With growing experience and theoretical development in this area, HIRA guidelines will be revised periodically.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.3
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• pp.363-367
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• 2006

The nutritional worth of Phalaris minor seeds was assessed in comparison to conventional cereal grains like maize and wheat. P. minor seeds had higher total ash and cell wall constituents as compared to wheat and maize grains. The CP content of P. minor was comparable to wheat grains but higher than maize grains. The in vitro studies revealed that the net gas production and availability of ME from P. minor was comparable to that of maize but the digestibility of nutrients was significantly (p<0.05) lower than that of conventional cereal grains. The digestion kinetic parameters for DM and CP revealed that P. minor had the highest (p<0.05) soluble fraction (a) followed by wheat and maize. Reverse trend was observed for insoluble but potentially degradable fraction (b). The effective and true DM and CP degradability was significantly (p<0.05) higher in wheat grains followed by that in P. minor and maize grains. The digestibility of OM and NDF was not affected by replacing cereal grains in concentrate mixture with P. minor seeds up to 75 per cent level. But the availability of ME from concentrate mixtures was comparable to control only up to 50% level of replacement. Replacement of cereal grains with P. minor did not affect the rapidly soluble fraction and insoluble but potentially degradable fraction of concentrate mixture containing P. minor up to 75 per cent, but it was depressed significantly at 100% replacement level. The effective and true degradability of DM of concentrate mixtures containing P. minor from 50 to 100 per cent was comparable to that of conventional concentrate mixture (CCM). The wheat based concentrate mixtures showed higher net gas production (208 vs. 201 ml/g DM/24 h), digestibility of nutrients and ME availability (9.64 vs. 9.54 MJ/kg DM) as compared to maize based concentrate mixture. The wheat based concentrate mixture had significantly (p<0.05) higher rumen undegradable fraction and effective degradability. The data conclusively revealed that conventional cereal grains could be replaced with P.minor seeds up to 75 per cent without affecting the availability of nutrients.

• Journal of the Korean Society for information Management
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• v.28 no.1
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• pp.285-308
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• 2011

This study examines user satisfaction in public libraries nationwide. It analyzes service quality factors that affect user satisfaction of public library patrons and identify sub-factors of service quality that affect the overall user satisfaction. User satisfaction factors were developed to measure library satisfaction in all aspects of the library service. Six variables were identified, including volume of books, staff, programs, facilities, online services, and information availability. According to survey findings, general library satisfaction was strongly correlated with information availability, facilities, and staff. Relatively lower levels of satisfaction were identified in the areas of online services and programs. All six service quality factors were statistically significantly associated with user satisfaction, where information availability, facilities, and volume of books showed stronger associations than the other three factors.

• Journal of the Korean Society of Safety
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• v.19 no.4 s.68
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• pp.55-59
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• 2004

In this study, the required life cycle cost is evaluated in consideration of the equipment's availability during its lift cycle. In order to meet the maximum availability required by the process, the failure cost and life cycle cost is assessed The optimal equipment selection method is presented according to the analysis of the failure cost and life cycle cost. For the systems in which equipments are connected serially, the optimal equipments are selected by minimizing the life cycle cost and satisfying the required system availability goal. In addition, the selection methods and lift cycle cost are analyzed according to the cost variation of the equipment. By using the life cycle evaluation procedure, the failure cost and maintenance cost needed during the life cycle of the equipment can be presented.

• Journal of Institute of Control, Robotics and Systems
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• v.5 no.5
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• pp.614-621
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• 1999

In this paper, the analytical appproaches are presented for jointly determining the profit-miximizing configuration of the fault-tolerance real time modular cell manufacturing system. The transient(time-dependent) analysis of Markovian models is firstly applied to modular cell manufacturing system from a performability viewpoint whose modeling advantage lies in its ability to express the performance that truly matters - the user's perception of it - as well as various performance measures compositely in the context of application. The modular cells are modeled with hybrid decomposition method and then availability measures such as instantaneous availability, interval availability, expected cumulative operational time are evaluated as special cases of performability. In addition to this evaluation, sensitivity analysis of the entire manufacturing system as well as each machining cell is performed, from which the time of a major repair policy and the optimal configuration among the alternative configurations of the system can be determined. Secondly, the recovery policies from the machine failures by computing the minimal number of redundant machines and also from the task failures by computing the minimum number of tasks equipped with detection schemes of task failure and reworked upon failure detection, to meet the timing requirements are optimized. Some numerical examples are presented to demonstrate the effectiveness of the work.