• Journal of the Korea Institute of Information Security & Cryptology
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• v.11 no.6
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• pp.41-51
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• 2001

Group signature schemes allow a group member to sign messages anonymously on behalf of the group. In case of dispute, only a designated group manager can reveal the identity of the member. During last decade, group signature schemes have been intensively investigated in the literature and applied to various applications. However, there has been no scheme properly handling the situation that a group member wants to leave a group or is excluded by a group manager. As noted in[3], the complexity of member deletion stands in the way of real world applications of group signatures and the member deletion problem has been a pressing open problem. In this paper we propose an efficient group signature scheme that allows member deletion. The length of the group public key and the size of signatures all independent of the size of the group and the security of the scheme relies on the RSA assumption. In addition, the method of tracing all signatures of a specific member is introduced.

• Journal of the Korean Society of Safety
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• v.36 no.4
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• pp.80-87
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• 2021

Risk assessment techniques are processes used to evaluate hazardous risk factors in construction sites, facilities, raw materials, machinery, and equipment, and to estimate the size of risk that could lead to injury or disease, and establish countermeasures. The most important thing in assessing risk is calculating the size of the risk. If the size of the risk cannot be calculated objectively and quantitatively, all members who participated in the evaluation would passively engage in establishing and implementing appropriate measures. Therefore, this study focused on predicting accidents that are expected to occur in the future based on past occupational accident statistics, and quantifying the size of the risk in an overview. The technique employed in this study differs from other risk assessment techniques in that the subjective elements of evaluators were excluded as much as possible by utilizing past occupational accident statistics. This study aims to calculate the size of the risk, regardless of evaluators, such as a manager, supervisor, safety manager, or employee. The size of the risk is the combination of the likelihood and severity of an accident. In this study, the likelihood of an accident was evaluated using the theory of Bud Accident Chainability, and the severity of an accident was calculated using the occupational accident statistics over the past five years according to the accident classification by the International Labor Organization.

• Journal of the Korea Society of Computer and Information
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• v.14 no.12
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• pp.139-145
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• 2009

This study proposes a model of collection process for real-time forensic data, in which the manager was to respond to infringement incidents in terms of system operation and inspection and to collect, analyze and restore forensic data immediately after an incident took place. The suggested model was modeled in seven processes according to functional elements. Unlike the old and managerial forensic processes, the model allowed the manager to react to infringement incidents in the aspects of system operation and inspection and to follow the processes of collecting, analyzing, and restoring forensic data in case of an incident. There also was a feedback process designed towards the step of gathering forensic data through the stages of systematizing reaction strategies in order that he or she be able to bring about comprehensive and structural responses to an incident like the former processes in which it is difficult to bring about instant responses.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.8
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• pp.5430-5441
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• 2015

The purpose of this study is to investigate the effect of Medicaid case management (CM) performed by Medicaid case managers on health management and to examine the overall health care utilization with high risk Medicaid beneficiaries. The subjects involved in this research were 113 Medicaid beneficiaries who were recipients CM in Y-gu between October 1st, 2012 and March 31th, 2013. The results show that there were significant differences in 'recognition of own disease', 'understanding of Medicaid policy', 'medication' and 'healthy lifestyle'. Also there were significant differences in 'appropriateness of health utilization', 'number of medical institutions', 'level of social isolation' and 'general health status'. In addition, significant differences were found in Medicaid days, outpatient days, medication days and Medicaid costs. It was found that the Medicaid CM had a positive effect on health care utilization. The study suggests the need of strengthening and diversifying Medicaid CM as well as supporting the management and monitoring after the termination of Medicaid CM.

• Korean Journal of Social Welfare Studies
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• v.40 no.2
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• pp.89-122
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• 2009

This study was carried out to analyze the job of care managers in their social welfare practicing fields about the frequency of care management duties they perform, types of duties considered to be most important and the reason, and types of jobs counted to be the most difficult and the reason by qualitative case study research methods. The job area of care management was elicited using DACUM method, and those 9 job areas derived from it were analysed according to frequency of performance, importance and difficulty. The subjects were 10 social workers serving more than 3 years with major duty of care management and chosen by reputational-case selection, and those collected data analysis was operated according to embedded analysis types. We discussed the implication of this research. : The experience of participants are the process of maintaining the tension, and search the equilibrium point between client centered service and institutional pressure. According to the results we proposed ① Construction of community based social work network, ② Institutional installation for guarantee care manager's Job competence ③ Standard manual for equilibrium and upward equalization

• Journal of Construction Engineering and Project Management
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• v.4 no.1
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• pp.29-36
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• 2014

Tunnelling has become a preferred method of construction for road and highway projects in countries with a lot of hilly slope geological conditions such as found in Malaysia. However the construction works of a tunnelling project are usually complicated and costly, which consequently impose great risks to the parties involved. This paper identifies the key significant risks and sub-risks for tunnelling construction projects in Malaysia through a case study. Interview has been used as the solitary means to determine the significant risks from contractor's eleven key project personnel who were directly involved in the tunnelling construction such as consultant, construction manager and tunnel engineers. The importance of the risks identified is then prioritised and ranked via the Analytic Hierarchy Process (AHP)'s pairwise comparison approach to determine their criticality towards a successful delivery of project. As a result, three key risks have been identified as significant for the tunnelling case study project, namely health and safety, cost overrun in construction and time overrun in construction. Two sub-risks each of the latter categories, which are cost underestimation and unforeseen events (cost overrun in construction) as well as plant and machinery failure and delay in material delivery (time overrun in construction), have occupied the top five overall risk ranking.

• Journal of Information Technology Services
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• v.19 no.4
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• pp.125-138
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• 2020

This paper proposes a more advanced livestock insurance product by comparing the status of livestock management in Korea with Netherlands case. The project focused on blockchain technology, IoT based management manual and planned livestock insurance related to Insurtech. The livestock insurance policy automatically stores information on each block through sensors attached to livestock, so that the livestock manager carries out follow-up manual for each livestock. Blockchain technology contains numerous advantages such as distributed ledger and irreversibility. However, the sharing of transparent information can be a burden to the policyholder. To compensate it, new business model needs to be proposed to provide incentives to the policyholder. We focused on the data of Gyeonggi Province, which suffered the most from African swine fever (ASF) in Korea. The corresponding Insurtech based livestock insurance can enable policyholders and insurers to build trust by sharing objective and transparent information, and maximize their respective profits by enabling mutual control.

• Proceedings of the Korea Concrete Institute Conference
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• 1998.04b
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• pp.695-702
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• 1998

The purpose of this study is to investigate the mechanical properties of precast concrete cured by accelerated curing methods such as, steam curing method and warm water curing method varing maximum temperature of curing along to the period of curing. Some specimens are cured by accelerated curing method(warm water curing method) and then deposited in the storehouse. The others are deposited in the storehouse directly. All of these are cured until being tested to compare these two group's mechanical characteristics for each period 3days, 7days, 28days. The goal of this comparison is to estimate the efficiency of accelerated curing method in the case of precast concrete stocked in the field or warehouse for a long term and to make guide line for factory manager to make a economical products of concrete of a good quality. We can conclude some guide lines 1) It is not efficient to cure concrete with accelerated method at higher than 80℃. 2) The continuing of curing period more than 36hr makes damage to concrete in using accelerated curing method. 3) The strength revelation of concrete cured by accelerated curing methods, added rice husk ash more delayed than OPC concrete done but the strength of maximum value is higher than OPC concrete. 4) It is not efficient to use accelerated curing method in the case of storing the products for more than 7days in the aspect of mechanical properties.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.18 no.spc
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• pp.63-74
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• 2020

The operational safety assessment is an important part of a safety case for the deep geological repository of spent fuels. It consists of different stages such as the identification of initiating events, event tree analysis, fault tree analysis, and evaluation of exposure doses to the public and radiation workers. This study develops a probabilistic safety assessment method for the operational safety assessment and establishes an assessment framework. For the event and fault tree analyses, we propose the advanced information management system for probabilistic safety assessment (AIMS-PSA Manager). In addition, we propose the Radiological Safety Analysis Computer (RSAC) program to evaluate exposure doses to the public and radiation workers. Furthermore, we check the applicability of the assessment framework with respect to drop accidents of a spent fuel assembly arising out of crane failure, at the surface facility of the KRS⁺ (KAERI Reference disposal System for SNFs). The methods and tools established through this study can be used for the development of a safety case for the KRS⁺ system as well as for the design modification and the operational safety assessment of the KRS⁺ system.

• The Journal of the Korea institute of electronic communication sciences
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• v.7 no.2
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• pp.425-431
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• 2012

In the case of outdoor moving of robot, it is differ to indoor moving case due to it cannot prepare map early for entire outdoor environments, there is nearly no research based on map because most outdoor robots use GPS. In this paper, we implement outdoor robot localization that using precision GPS and then GPS data applying MCL algorithm in outdoor environments of plane of 2 dimensional without incline section. We also perform a simple mission scenario by using applied robot localization in outdoor robot. We applying OpenRTM based on middleware, we can be controlled and grasped situation of the outdoor robot by remote through server by manager.