• 한국정보통신학회논문지
• /
• 제20권12호
• /
• pp.2243-2251
• /
• 2016

본 연구에서는 트리구조를 가지는 네트워크의 [1,2]-지배집합에 대한 특성과 지배수의 상계 값에 대한 이론적 모형을 제시하였다. 구체적으로는 트리 네트워크가 가지는 몇 가지 전형적인 제약에 대해서 각 유형이 가지고 있는 지배집합의 지배수의 상계 값을 도출하였다. 본 논문에서는 트리구조의 네트워크에 대한 특성을 해석함에 있어서 그래프이론을 적용하였다. 노드집합 V와 링크집합 E으로 구성되는 그래프 G=(V,E)에 대해서 노드집합 V의 부분 집합 D를 가정한다. 이때 집합 V에 속하면서 집합 D에 속하는 않는 임의의 노드 ${\upsilon}$가 D에 속하는 노드와 1개 이상 2개 이하로만 인접하여 있으면 D를 [1,2]-지배집합이라 한다. 그리고 그래프 G의 [1,2]-지배집합 중 최소 농도를 [1,2]-지배 수라 하고 ${\gamma}_{[1,2]}(G)$로 표시한다. 본 논문에서는 트리(tree)의 [1,2]-지배 수에 대한 특성과 이의 새로운 상계 값을 증명하였다.

• 한국콘텐츠학회:학술대회논문집
• /
• 한국콘텐츠학회 2009년도 춘계 종합학술대회 논문집
• /
• pp.851-855
• /
• 2009

무선 ad-hoc 네트워크에서 CDS(connected dominating set)을 구성할 때 보다 빠르고 간단하며 효율적인 전력 소모 관리가 가능한 알고리즘이 필요하다. 무선으로 구성되어 있는 네트워크의 특성상 소비전력을 최소화 하는 것이 가장 중요하다. 노드가 집중되어 있거나 잦은 CDS 재구성을 할 경우 데이터를 공유하는 ad-hoc 네트워크의 특성상 충돌 및 지연현상에 의해 병목현상이 나타나 정보를 손실할 우려가 많다. 따라서 지속적인 위치 이동이 이루어지지 않는 무선 ad-hoc 네트워크에서는 가장 효율적인 CDS를 결정하고 망구성이 이루어진 후 가급적 재구성하지 않아야 한다. 본 논문에서는 연결된 노드 수와 잔여 전력에 대한 가중치를 부여하여 구성된 CDS 기반 네트워크 알고리즘을 기반으로 노드 구성에 따른 각 상황에서의 성능을 비교 평가하였다.

• 한국군사과학기술학회지
• /
• 제15권6호
• /
• pp.770-778
• /
• 2012

In this paper, we propose a multi-path construction scheme to improve the survivability of a multicast session in military hybrid networks. A military hybrid network consists of a static backbone network and multiple mobile stub networks where some nodes are frequently susceptible to be disconnected due to link failure and node mobility. To improve the survivability of multicast sessions, we propose a construction scheme of ${\kappa}$ redundant multi-paths to each receiver. In order to take account of different characteristics of static and mobile networks, we propose quite different multi-path setup approaches for the backbone and stub networks, respectively, and combine them at the boundary point called gateway. We prove that our proposed scheme ensures that each receiver of a multicast session has ${\kappa}$ redundant paths to the common source. Through simulations, we evaluate the performance of the proposed schemes from three aspects : network survivability, recovery cost, and end-to-end delay.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제9권10호
• /
• pp.4126-4142
• /
• 2015

Finger vein recognition is a biometric technology using finger veins to authenticate a person, and due to its high degree of uniqueness, liveness, and safety, it is widely used. The traditional Symmetric Local Graph Structure (SLGS) method only considers the relationship between the image pixels as a dominating set, and uses the relevant theories to tap image features. In order to better extract finger vein features, taking into account location information and direction information between the pixels of the image, this paper presents a novel finger vein feature extraction method, Multi-Orientation Weighted Symmetric Local Graph Structure (MOW-SLGS), which assigns weight to each edge according to the positional relationship between the edge and the target pixel. In addition, we use the Extreme Learning Machine (ELM) classifier to train and classify the vein feature extracted by the MOW-SLGS method. Experiments show that the proposed method has better performance than traditional methods.

• Journal of Information Processing Systems
• /
• 제13권5호
• /
• pp.1277-1298
• /
• 2017

Related to the maximum vector problem, a skyline query is to discover dominating tuples from a set of tuples, where each defines an object (such as a hotel) in several dimensions (such as the price and the distance to the beach). A tuple, an instance of an object, dominates another tuple if it is equally good or better in all dimensions and better in at least one dimension. Traditionally, skyline queries are defined upon single-instance data or upon objects each of which is associated with an instance. However, in some cases, an object is not associated with a single instance but rather by multiple instances. For example, on a review website, many users assign scores to a product or a service, and a user's score is an instance of the object representing the product or the service. Such data is an example of multi-instance data. Unlike most (if not all) others considering the traditional setting, we consider skyline queries defined upon multi-instance data. We define the dominance calculation and propose an algorithm to reduce its computational cost. We use synthetic and real data to evaluate the proposed methods, and the results demonstrate their utility.

• The Journal of Asian Finance, Economics and Business
• /
• 제8권2호
• /
• pp.151-164
• /
• 2021

The paper identifies the enablers (drivers) and inhibitors (barriers) influencing e-customs implementation in Vietnam (known as a developing country with a lower technological environment) along with determining the impact of e-customs on firm performance. The survey was conducted with the representatives (managers) of firms in five cities and provinces dominating Vietnam's international trade. The data was analyzed using structural equation modeling (SEM). The findings show two significant drivers (enablers) - relative advantages and national culture, while compatibility and ease of use are the barriers. Previous studies showed that cultural dimensions related to 'uncertainty acceptance' and 'individualism' encourage innovation; however, this paper demonstrates that 'uncertainty avoidance' and 'collectivism' promote e-customs deployment in Vietnam. Previously, Vietnamese culture was known for scoring high on cultural dimensions related to 'power distance' and 'short-term orientation'. However, today, as an emerging country, Vietnamese has switched to 'low distance' and 'long-term orientation', especially in terms of e-customs innovation. Additionally, the paper also emphasized that e-customs implementation had a positive influence on firm performance in Vietnam. Based on the results of the paper, policy-makers can devise essential solutions to enhance e-customs implementation as well as managers of firms can set-up strategies to adapt to the modernized environment.

• KIEAE Journal
• /
• 제10권2호
• /
• pp.9-18
• /
• 2010

As an aging population has increased vastly and nuclear families have been a dominating family type in modern Korean society, the numbers of the elderly who suffer Empty Nest Syndrome and LID (Loss Isolation Depression) syndrome have been accelerated. These syndromes involve psychological instability, melancholy, and lethargy. To make the elderly get out of this phenomenon and live actively, the scheme of converting their existing house into shared housing was set as a hypothetical solution in this study. This study sets out to find out responses of the elderly to alter their own house's function in housing improvement area. A Small Workshop Panel method was used and the elderly aged 55 years upwards took part and they own a detached house in a housing improvement area that is relatively large for the elderly or the elderly couple to live alone. Through the workshop, problems that the elderly have been experiencing within their houses were looked into and responses of the elderly on altering their house to shared housing by introducing developed schematic plans. Although, the first response was negative, positive responses from the house owners were carried out when a visual support i.e. developed shared housing plan was provided. The positive response was based on the fact that subsidies from the government on house renovation and tenants matching programs are supported as shared housing could provide home owners economical support with rents and help them to feel less lonely. This is a way of relieving the elderly from being neglected and supporting them to live and age actively in their later lives. Furthermore, by providing a visual media to the elder residents in housing improvement area, their greater understandings on the development and addressing their opinions were possible. Therefore, more tools that promote elder residents' participation are needed for future housing improvement projects and an aging society.

• 한국주거학회:학술대회논문집
• /
• 한국주거학회 2008년 추계학술발표대회 논문집
• /
• pp.131-134
• /
• 2008

The numbers of the elderly who suffer Empty Nest Syndrome have been accelerated as an aging population has increased vastly and nuclear families have been a dominating family type in modern Korean society. To make the elderly get out of this phenomenon and live actively, the scheme of converting their existing houses into shared houses was set as a hypothetical solution in this study, and finding out the responses of the elderly who owns their own houses is the purpose of the study. A small workshop panel method was used and the elderly aged 55 years upwards took part and they own a detached house that is relatively large for the elderly or the elderly couple to live alone. The workshop was consisted of 3 stages: 1. a survey 2. an interview 3. a site visit. Through this, problems that the elderly have been experiencing within their houses were looked into and the responses of the elderly on converting their houses to shared houses by introducing developed schematic plans. As a result, positive responses from the house owners were carried out based on the fact that subsidies from the government on house renovation and tenants matching programs are supported. Shared houses could provide home owners economical support with rents and help them to feel less lonely. This is one way of supporting the elderly to live and age actively in their later lives. Therefore, this idea should be established in connection with preparing aging, aged, and super-aged society.

• 한국산림과학회지
• /
• 제52권1호
• /
• pp.58-71
• /
• 1981

충남(忠南) 전북지방(全北地方) 적송림(赤松林)의 천이과정(遷移過程)을 연구(研究)하기 위하여 솔잎혹파리의 피해지속기간(被害持續期間)에 따라 피해극기지(被害極基地) (5년전(年前)에 피해발생(被害発生))인 공주(公州)(A), 피해지속지(被害持續地)(10년전(年前)에 피해발생(被害発生))인 부여(扶餘)(B), 피해회복지(被害回復地)(20년전(年前)에 피해발생(被害発生))로서 고창지역(高敞地域)(C)을 조사지역(調査地域)으로 설정(設定)하고, 각(各) 조사지역별(調査地域別)로 환경요인(環境要因)과 식생상태(植生狀態)를 調査하여, 환경요인(環境要因)과 식생상태(植生狀態), 삼림군집(森林群集)의 비교(比較), 식물상(植物相)의 변화(変化) 등(等)을 분석(分析)한 결과(結果)를 요약(要約)하면 다음과 같다 1. 임분(林分)이 솔잎혹파리피해(被害)로 부터 회복(回復)되어 감에 따라 식생구성(植生構成)에 변화(変化)가 오고 대상수종(代償樹種)으로 발달(発達)된 참나무류(類)의 상대우점치(相対優点値)가 감소(減小)되었다. 그러나 본(本) 조사지역내(調査地域內)에서는 상수리나무의 상대우점치(相対優点値)가 다른 참나무류(類) 보다 높았다. 2. 솔잎혹파리피해(被害)가 지속(持續)됨에 따라 삼림군집(森林群集)의 종구성상태(種構成狀態)가 점차 다양(多樣)하여진다. 그후 피해(被害)가 회복(回復)됨에 따라 임분(林分)의 종구성상태(種構成狀態)는 단순화(单純化)되는 것으로 나타났다. 3. 상대밀도(相対密度) 및 상대우점치(相対優点値)의 상대치(相対値)에 의(依)한 식생천이(植生遷移)를 종합분석(綜合分析)한 결과(結果) 솔잎혹파리피해(被害)의 극심(極甚)에서 우점종(優点種)을 이루던 참나무류(類)가 피해(被害)로부터 회복(回復)되어감에 따라 그 값이 감소(減少)되고, 싸리류(類), 진달래류(類) 등(等)이 하층식생(下層植生)을 형성(形成)하는 삼림군집(森林群集)으로 변화(変化)하여 갔다. 4. 식생(植生)에 미친 토심(土深), 토양함수량(土壤含水量), 유기물함량(有機物含量), 그리고 유기물층(有機物層)의 두께는 본(本) 조사대상지(調査対象地)의 범위내에 있어서는 거의 같은 것으로 사료(思料)되었고 연평균강수량(年平均降水量)과 온도(温度)도 유사(類似)하였다고 본다.