• Journal of the Korean Society for Railway
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• v.10 no.2 s.39
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• pp.179-185
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• 2007

In large station with high density traffic, trains can be hardly controlled by CTC but by station dispatcher because CTC has difficulties in monitoring all states of affairs happening within each station such as departures, arrivals of many trains from different lines and shunting of trains to move between yards and platforms, etc. Therefore the station's dispatcher has to make quick decision about how to reschedule the times and routes for all the trains scheduled within a specific time window. And such decision becomes harder when an unexpected delay occurs because a delay occurring in a train propagates other trains as time goes on. Generally, it is called the conflict detection and resolution to adjust beforehand the distorted schedule due to a delay to original schedule. Our research is different from the state of the arts in that ours determines simultaneously the routes and the times of arrival and departure of trains, although others do only the arrival and departure time of the trains without considering the alternative routes and shunting of the station. This study suggests a mathematical approach for how to detect in advance and resolve efficiently the conflicts occurring within a station and it will be shown how to reduce delay using our approach by means of analysing the schedule of ChyungRyangRi station.

• IE interfaces
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• v.23 no.1
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• pp.24-34
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• 2010

In the telecommunication system which is based on the existing PSTN(public switched telephone network), feature interaction has been an important research issue in order to provide seamless services to users. Recently, rapid proliferation of IP-based network and the various types of IP media supply services, the feature interaction from the perspective of application services has become a significant aspect. This paper presents conflict detection and resolution algorithms for designing and operating a variety of services that are provided through IP-based network. The algorithms use explicit service interactions to detect conflicts between a new service and registered services. They then apply various rules to reduce search space in resolving conflicts. The algorithms are applied to a wide range of realistic service provision scenarios to validate that it can detect conflicts between services and resolve in accordance with different rule sets. By applying the algorithms to various scenarios, it is observed that the proposed algorithms can be effectively used in operating an IP-based services network.

• Proceedings of the Korea Society for Simulation Conference
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• 2005.11a
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• pp.51-55
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• 2005

Assuring integrity of permission assignment (PA) constraints is a difficult task in role-based access control (RBAC) because of the large number of constraints, users, roles and permissions in a large enterprise environment. We provide solutions for this problem using the conflict concept. This paper introduces the conflict model in order to understand the conflicts easily and to detect conflicts effectively. The conflict model is classified as a permission-permission model and a role-permission model. This paper defines two type conflicts using the conflict model. The first type is an inter-PA-constraints (IPAC) conflict that takes place between PA constraints. The other type is a PA-PAC conflict that takes place between a PA and a PA constraint (PAC) Also, the conditions of conflict occurrence are formally specified and proved. We can assure integrity on permission assignment by checking conflicts before PA and PA constraints are applied.

• Proceedings of the KSR Conference
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• 2008.11b
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• pp.687-694
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• 2008

Given the daily tactical schedule, the purpose of the traffic management system is to develop operating plan that will achieve the stated schedule as best as possible. The operating plan has to be modified during the day because of occurring disturbance(e.g. delay, infrastructure breakdown, etc.) Conflict detection and resolution(CDRS) are aimed for adjusting the distorted schedule to tactical schedule. Our research separate CDRS into two hierarchy modules, line conflict control module and station conflict control module. We define the role of each modules and design the cooperative architecture. We suggest the conflict detection and resolution approach based on mathematical model. These results can be implemented as prototype modules.

• The KIPS Transactions:PartA
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• v.18A no.1
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• pp.19-24
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• 2011

As era of multi-core processors has arrived, transactional memory has been considered as an effective method to achieve easy and fast multi-threaded programming. Various hardware transactional memory systems such as UTM, VTM, FastTM, LogTM, and LogTM-SE, have been introduced in order to implement high-performance multi-core processors. Especially, LogTM-SE has provided study performance with an efficient memory management policy and a practical thread scheduling method through conflict detection based on signatures. However, increasing number of cores on a processor imposes the hardware complexity for signature processing. This causes overall performance degradation due to the heavy workload on signature comparison. In this paper, we propose a new architecture of multiple signature comparison to improve conflict detection of signature based transactional memory systems.

• Journal of Communications and Networks
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• v.3 no.4
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• pp.365-373
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• 2001

We propose a new channel reservation protocol which can reduce message delay by using a counter for detection of d source conflict in a WDM single-hop network with non-equivalent propagation delay. A source convict occurs when a source node has the right to transmit more than or equal to two messages simultaneously, which are transmitted using different wavelengths. In such a case, the source node has to newly obtain the right to transmit the message. In the proposed protocol, by using a source conflict counter a source node can detect a source conflict before a wave-length assignment is performed. Therefore, the source node can start a procedure to newly obtain the right to transmit the message which cannot be transmitted due to a source conflict. We analyse the throughput performance by taking the effect of a source conflict into account, and show that the approximate analysis and the computer simulated results are close. Also, from computer simulated results, we show that our proposed protocol can reduce mean message delay dramatically without degrading throughput performance as the offered load becomes large.

• ETRI Journal
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• v.29 no.3
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• pp.311-321
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• 2007

In this paper, we propose a user-centric conflict management method for media services which exploits personal companions for the harmonious detection and resolution of service conflicts. To detect conflicts based on the varying characteristics of individual users, the proposed method exploits the unified context describing all users attempting to access media services. It recommends and mediates users' preferred media contents through a shared screen and personal companions to resolve the detected conflicts. During the recommendation, a list of preferred media contents is displayed on the shared screen, and a personally preferred content list is shown on the user's personal companion comprising the selection of media contents. Mediation assists the selection of a consensual service by gathering the users' selections and highlighting the common media contents. In experiments carried out in a ubiHome, we observed that recommendations and mediation are useful in harmoniously resolving conflicts by encouraging user participation in conflict situations.

• Journal of the Korean Society for Railway
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• v.18 no.6
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• pp.619-629
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• 2015

The train conflict resolution problem refers to an adjustment of the train operation schedule in order to minimize the delay propagation when a train conflict is predicted or when a train conflict occurs. Previous train studies of train conflict resolutions are limited in terms of the size of the problems to be solved due to exponential increases in the variables. In this paper, we propose a train conflict resolution model using a time-space network to solve the train conflict situation in the operational phase. The proposed model adjusts the size of the problem by giving only the dwell tolerance in the time-space network only for stops at the station after a train conflict. In addition, the proposed model can solve large problems using a path flow variable. The study presents a train delay propagation analysis and experimental results of train conflict resolution assessments as well using the proposed model.

• Journal of KIISE:Databases
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• v.35 no.2
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• pp.112-124
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• 2008

RDF and OWL are the primary base technologies for implementing Semantic Web. Recently, many researches related with them, or applying them into the other application domains, have been introduced. However, relatively little work has been done for securing the RDF and OWL data. In this article, we briefly introduce an RDF triple based model for specifying RDF access authorization related with RDF security. Next, to efficiently find the authorization conflict by RDF inference, we introduce a method using prime number graph labeling in detail. The problem of authorization conflict by RDF inference is that although the lower concept is permitted to be accessed, it can be inaccessible due to the disapproval for the upper concept. Because by the RDF inference, the lower concept can be interpreted into the upper concept. Some experimental results show that the proposed method using the prime number graph labeling has better performance than the existing simple method for the detection of the authorization conflict.

• Science of Emotion and Sensibility
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• v.16 no.3
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• pp.341-350
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• 2013

The present study aimed to understand the sensory characteristic of change detection by comparing the experience of detecting a salient visual change against the experience of detecting a sensory conflict evoked by a binocular mismatch. In Experiment 1, we used the change detection task where 2, 4, or 6 items were short-term remembered in visual working memory and were compared with following test items. The half of change-present trials were manipulated to elicit a binocular rivalry on the test item with the change by way of monocular inputs across the eyes. The results showed that change detection accuracy without the rivalry manipulation declined evidently as the display setsize increased whereas no such setsize effect was observed with the rivalry manipulation. Experiment 2 tested search efficiency for the search array where the target was designated as an item with the rivalry manipulation, and found the search was very efficient regardless of the rivalry manipulation. The results of Experiment 1 and 2 showed that when the given memory load varies, the experience of detecting a salient visual change become similar to the experience of detecting a sensory conflict by a binocular rivalry.