• 한국컴퓨터정보학회논문지
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• 제21권8호
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• pp.41-48
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• 2016

In this paper, we propose an election protocol based on mobile ad-hoc network. In distributed systems, a group of computer should continue to do cooperation in order to finish some jobs. In such a system, an election protocol is especially practical and important elements to provide processes in a group with a consistent common knowledge about the membership of the group. Whenever a membership change occurs, processes should agree on which of them should do to accomplish an unfinished job or begins a new job. The problem of electing a leader is very same with the agreeing common predicate in a distributed system such as the consensus problem. Based on the termination detection protocol that is traditional one in asynchronous distributed systems, we present the new election protocol in distributed systems that are based on MANET, i.e. mobile ad hoc network.

• 한국컴퓨터정보학회논문지
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• 제8권4호
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• pp.35-40
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• 2003

분산시스템 환경에서, 흩어져 있는 다양한 형태의 자원들을 통제하고 관리하기 위해서는 분산된 여러 프로세스들 가운데 조정자(coordinator)로서의 역할을 담당할 특별한 프로세스를 필요로 한다. 이러한 조정자 프로세스를 통상 리더(leader)라고 부르며 리더를 선출하기 위한 알고리즘은 신뢰성있는 분산시스템을 구축하는 데 필수적인 중요한 요소가 된다. 이 논문에서는 특별히 failure detector(FD)를 구현한 비동기 분산시스템 환경에서 선출 문제 및 컨센서스 문제 간의 상관관계를 통해 제기되는 문제를 다루고자 한다. 먼저, 시스템 모델을 정의하고 그 다음으로 리더 선출을 설명한 후 마지막으로 축소 프로토콜을 이용하여 선출 문제가 컨센서스 문제에 비해 상대적으로 어려움을 증명하도록 할 것이다.

• 임상간호연구
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• 제29권1호
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• pp.75-84
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• 2023

Purpose: This study developed a protocol for nursing care after death for adult patients in hospitals. Methods: This was a methodological study to develop a care after death protocol. The preliminary protocol was developed based on a literature review, guidelines, and practice recommendations from groups of experts and clinical nurses. Content validity was evaluated by a group of experts (n=6) and nurses (n=30) in two hospitals. Results: The preliminary protocol recommendations were modified by validation and the open-question analysis results. The final protocol comprised three general recommendations and 43 recommendations in five steps that are verification and notification of a death, personal care of the body, viewing the patient, patient transfer, and documentation and self-care. Conclusion: This study result provides nurses with a consensus information on patient care after death and family support in a hospital setting. This nursing protocol is expected to improve the quality of care after death for adult patients and their families, and can be used for developing educational and emotional support for nurses to accomplish their important role.

• 정보보호학회논문지
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• 제28권1호
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• pp.5-14
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• 2018

최근 4차 산업혁명으로 인해 사물인터넷 기반의 다양한 기술들이 활발하게 연구되고 있다. 사물인터넷 시대에는 기존 서버-클라이언트 구조의 중앙 집중형 운영보다는 서버에 부하를 줄이고 자율적인 사물간 데이터 통신에 적합한 피어-피어 구조의 분산형 운영방식이 요구 되고 있다. 본 논문에서는 데이터에 대한 무결성과 영속성을 지원하는 새로운 형태의 분산형 데이터베이스 기술인 블록체인에 대해 설명하고, 보안성을 분석한다. 이를 위해 블록체인의 주요한 동작을 합의 과정, 네트워크 통신 과정, 키 관리 과정으로 구분하여 각 과정에서의 가능한 공격과 대응책을 설명한다. 또한 대표적인 암호화폐 플랫폼인 비트코인과 이더리움에서 발생했던 공격들에 대해 기술한다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제46권5호
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• pp.358-360
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• 2020

The management of odontogenic keratocysts (OKC) remains a hotly debated topic in oral and maxillofacial surgery. Despite numerous studies and systematic reviews on treatment options, there is a lack of consensus and no accepted protocol on the management of OKC. Hence, the aim of this study was to briefly summarize all large systematic reviews in the literature on the management of OKC and formulate an evidence-based management protocol. Data from five large systematic reviews were combined to calculate the mean recurrence rate for each technique. Decompression followed by enucleation along with adjuvant methods such as application of Carnoy's solution and peripheral ostectomy can result in very low recurrence and is an acceptable first line treatment. The surgical approach should be determined by lesion size, patient age, proximity to vital structures, accessibility, soft tissue/cortical perforation, and if the lesion is recurrent.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제24권4호
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• pp.325-336
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• 2021

The occurrence of functional gastrointestinal disorders (FGIDs) is a formidable challenge for infants, parents, and healthcare professionals. Although data from the Middle East are scarce, experts consider FGIDs a prevalent condition in everyday clinical practice. The new Rome IV criteria revisited the definitions from a clinical perspective to provide a practical and consistent diagnostic protocol for FGIDs. However, the treatment practices for functional disorders vary considerably among Middle Eastern countries, often resulting in mismanagement with unnecessary investigations and treatments. In addition, the role of various treatment modalities, including probiotics such as Lactobacillus reuteri DSM 17938, in FGIDs requires further discussion and evaluation. During a consensus meeting, a locally relevant approach for treating common FGIDs such as infant regurgitation, infant colic, and functional constipation was discussed and approved by regional experts. The participants suggested a simplified treatment plan and protocol for general pediatricians and other primary care physicians managing FGIDs. This easy-to-follow standardized protocol will help streamline the initial management of this complex disorder in the Middle East region and even globally.

• 한국항공우주학회지
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• 제36권10호
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• pp.988-995
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• 2008

본 논문에서는 궤환선형화를 이용한 일치기법을 사용하여 다수 무인기의 편대비행 제어기를 설계하였다. 제안한 기법은 한 대의 리더기를 중심으로 하는 집중형 방식이 아닌 분산형 방식으로, 각 개체의 제어입력은 인접한 개체만의 정보만을 이용하여 설계된다. 라플라시안 행렬을 이용하여 개체 간의 정보 교류를 정의한 후, 궤환선형화 과정을 거친 비행체에 적용하였다. 또한, 본 논문에서 제안한 제어기의 안정성 해석을 수행하였다. 또한 제안한 제어기의 성능을 검증하기 위해서 회전익 무인기 비행체 모델에 대한 수치 시뮬레이션을 수행하였다.

• International Journal of Computer Science & Network Security
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• 제23권5호
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• pp.128-134
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• 2023

The widespread usage of blockchain technology in cryptocurrencies has led to the adoption of the blockchain concept in data storage management systems for secure and effective data storage and management. Several innovative studies have proposed solutions that integrate blockchain with distributed databases. In this article, we review current blockchain databases, then focus on two well-known blockchain databases-BigchainDB and FalconDB-to illustrate their architecture and design aspects in more detail. BigchainDB is a distributed database that integrates blockchain properties to enhance immutability and decentralization as well as a high transaction rate, low latency, and accurate queries. Its architecture consists of three layers: the transaction layer, consensus layer, and data model layer. FalconDB, on the other hand, is a shared database that allows multiple clients to collaborate on the database securely and efficiently, even if they have limited resources. It has two layers: the authentication layer and the consensus layer, which are used with client requests and results. Finally, a comparison is made between the two blockchain databases, revealing that they share some characteristics such as immutability, low latency, permission, horizontal scalability, decentralization, and the same consensus protocol. However, they vary in terms of database type, concurrency mechanism, replication model, cost, and the usage of smart contracts.

• Journal of Chest Surgery
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• 제46권6호
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• pp.467-470
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• 2013

The rupture of a renal artery aneurysm is a rare disease that is difficult to diagnose. Although we usually consider the appropriate treatment to be open laparotomy with aortic aneurysm surgery or stenting with graft insertion through intravascular intervention, thus far, there is no general consensus on the treatment protocol for renal artery aneurysm. Notably, ruptured renal artery aneurysm is a true critical emergency that may result in a fatal outcome. We are reporting two renal artery aneurysm patients who had ruptured and underwent emergency laparotomy.

• 정보보호학회지
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• 제2권4호
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• pp.17-29
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• 1992

본 논문에서는 시스템 내의 모든sote들에게 분산되어 있는 정보들을 수렴하여 일치를 이루고, 그 결과를 모든 site들이 알도록 하는 다중 일치 프로토콜을 위한 효과적인 통신 방법을 제안하고자 한다. 분산 시스템에 참여하는 computer 또는 site들의 수를 N이라 할때, $O(N^2)$의 message를 필요로하면서 한 round안에 일치를 이룰 수 있는 프로토콜은 message의 수가 너무 많다는 것이 단점이다. 이에 본 논문에서는 Finite Projective Planes을 이용하여 message의 수를 줄이면서 두 round 안에 일치를 이룰 수 있는 통신 방법을 제안한다. 이때, 각 round마다 필요한 message의 수는 O(N$)이다. 또한, 이 통신 방법에서 이용되는 Finite Projective Planes을 구축하는 알고리즘을 제안하고자한다.