• International Journal of Computer Science & Network Security
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• v.22 no.10
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• pp.230-236
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• 2022

Objectives: The primary goal of this article is to compare the multiple algorithms used for deadlock handling methods and then outline the common method in deadlock handling methods. Methods: The article methodology begins with introducing a literature review studying different algorithms used in deadlock detection and many algorithms for deadlocks prevented, recovered, and avoided. Discussion and analysis of the literature review were done to classify and compare the studied algorithms. Findings: The results showed that the deadlock detection method solves the deadlock. As soon as the real-time deadlock detection algorithm is identified and indicated, it performs better than the non-real-time deadlock detection algorithm. Our novelty the statistics that we get from the percentages of reviewing outcomes that show the most effective rate of 47% is in deadlock prevention. Then deadlock detection and recovery with 28% finally, a rate of 25% for deadlock avoidance.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.23 no.58
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• pp.49-58
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• 2000

In order to resolve a deadlock problem in manufacturing systems, three main methods have been proposed-prevention, avoidance, and recovery. The prevention and avoidance methods require predicting deadlocks in advance in order to prohibit them. In contrast, the recovery method allows a system to enter a deadlock state, then resolves it usually using a common buffer. In this paper, a deadlock recovery method considering the impact of flexible job routings is proposed. This method is based on capacity-designated directed graph (CDG) model representing current requesting and occupying relations between Jobs and resources in order to detect a deadlock and then recovers it.

• Journal of Institute of Control, Robotics and Systems
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• v.13 no.7
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• pp.677-682
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• 2007

Concurrent competition for finite resources by multiple parts in flexible manufacturing systems(FMS's) and inappropriate initial marking or net structure of Petri net with share resources results in deadlock. This is an important issue to be addressed in the operation of the systems. Deadlock is a system state so that some working processes can never be finished. Deadlock situation is due to a wrong resource allocation policy. In fact, behind a deadlock problem there is a circular wait situation for a set of resources. Deadlock can disable an entire system and make automated operation impossible. Particularly, an unmanned system cannot recover from such a status and a set of jobs waits indefinitely for never-to-be-released resources. In this paper, we proposed a deadlock prevention method using siphon and trap of Petri net. It is based on potential deadlock which are siphon that eventually became empty. This method prevents the deadlock by the control of transition fire and initial marking in the Petri net. An given example of FMS is shown to illustrate our results with deadlock-free.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.20 no.11
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• pp.2131-2136
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• 2016

Before Industry 4.0, a purpose of manufacturing processes is simply overcoming the weakness of product line. However, Industry 4.0 should determine its method of work of facilities' own accord. Manufacturing processes such as FMS, AMS, MAS have been developed in these procedures, but there are possibilities of deadlock that can be happened for the reason of machine, agent or resource sharing. There were many studies to solve this problem. However, studies about prevention of deadlock happened in the situation that manufacturing processes are reconfigured dinamically because of human's intervention are incomplete. This paper proposes the model of the situation reconfigured dinamically and the method to prevent the deadlock in this situation. The proposed method adjusts production and manufacturing time by broadcasting time error messages to machines around when the manufacturing time of machine intervened by human is changed. Through this, it is anticipated to prevent the deadlock if conditions of the product line are changed.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.23 no.2
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• pp.73-78
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• 2023

The dining philosophers problem(DPP) is that five philosophers sit around a round table and eat spaghetti(or noodles) together, where they must have a pair of chopsticks(two) on both sides of them to eat, and if all philosophers have one chopstick on the right, no one can eat because the deadlock occurs. Deadlocks are a problem that frequently occur in parallel systems, and most current operating systems(OS) cannot prevent it. This paper proposes a silver bullet that causes no deadlock in an OS where all processors of 2≤n≤∞ have multiple parallel processing capabilities. The proposed method is a group round-robin method in which ⌊n/2⌋ odd processors form a group and perform simultaneously, and shift right to the next processor when execution ends. The proposed method is to perform two times for even processors, three times for odd processors per one round-robin. If the proposed method is performed n times, even-numbered processors perform n/2 times and odd-numbered processors perform (n-1)/2-times.

• Proceedings of the Korea Multimedia Society Conference
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• 1998.10a
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• pp.106-111
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• 1998

본 연구의 목적은 트랜잭션 순서화 기법중 데이터 우선순위 알고리즘(DPLP: Data-Priority Based Locking Potocol)의 높은 재시작 비율을 낮추고, 시스템의 처리 효율을 향상 시키는 것이다. 이를 위해서 트랜잭션을 일정한 크기의 그룹으로 그룹핑하고, 같은 그룹에 있는 트랜잭션은 선점권을 인정함으로써 자원을 점유하고 있는 트랜잭션에게 우선순위를 상속하여 트랜잭션의 재시작 비율을 낮춘다. 낮은 트랜잭션이 데이터를 장시간 잠금(lock)하는 것을 방지하기 위해서 그룹 우선순위를 적용한다. 상속에 의한 데드락 방지를 위해서 충돌전에 다른 데이터의 잠금여부를 검사한다. 성능을 평가하기 위해서 분산 데이터 베이스 시스템으로 시뮬레이션 환경을 구축하여 기존의 기법들과 성능을 비교하였다. 성능 비교 결과는 본 논문에서 제안하는 데이터 우선순위 상속 알고리즘이 기존의 상속 알고리즘과 데이터 우선순위 알고리즘 보다 성능이 우수함을 확인하였다.

• Journal of Korean Tunnelling and Underground Space Association
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• v.23 no.6
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• pp.371-384
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• 2021

Underground space, especially very-deep tunnel development in urban area, is a good alternative to solve the problem of insufficient ground space, and the need for underground space development is steadily increasing. However, due to the complex and time-consuming nature of design and construction, public conflicts related to the deep tunnel project are getting aggravating and more complex. In addition, since the public budget is mainly invested, when civil complaints arise, they often respond passively, resulting in amplification of conflicts or prolonging the deadlock in many cases. In this study, by analyzing the progress of major conflicts related to the construction of very-deep tunnels in urban area, the causes of conflicts, factors prolonging conflicts, and solutions are reviewed. Through a survey targeting ordinary citizens and tunnel experts, thoughts about the deep tunnel construction and major conflict factors were analyzed, and suggestions for minimizing conflicts were presented. The results of this study can be used to prepare alternatives such as various public involvement measures and improvement of project procedures to form a civic consensus on the construction of very-deep tunnels, and to prepare measures to improve prejudice against very-deep tunnels.