인터넷을 통한 동기화 된 캡션 및 동영상 데이터베이스에 관한 설계 및 구현

홍동권,박기현,신승봉 계명대학교 산업기술연구소 1998 産業技術硏究所 論文報告集 Vol.21 No.1

Current information society requires effective ways to process multimedia data like image, audio, video and so on, Many public of private information providers gather, store multimedia information and supply a different kind of multimedia data to users in everywhere. Most of users nowadays access multimedia data via internet. Audio and video data are usually transmitted to users by using streaming technology for instant replay. In this paper, we investigate database design techniques for effective retrieval of video segment and replay method of retrieved videos, Especially we shows the design and implementation technique for closed captioning of streaming file.

머리염색이 인체에 미치는 영향

윤형식,황성호,이현륭,김수호,박연석,권낙현,정호진,김동훈,노현주,홍성호,박병찬,이관,정해관 東國大學校醫學硏究所 2002 東國醫學 Vol.9 No.1

일상생활에서 모발염색은 흔히 접할 수 있는 미용의 한 종류로 특히 젊은층을 중심으로 폭발적으로 유행하고 있다. 염색을 위항 사용하는 약제는 표백제와 발색제 등 각종 화학약품이 사용되고 있으나 이로 인한 건강장해에 대한 연구는 그리 많지 않다. 저자들은 염색이 인체의 모발건강에 미치는 영향을 파악하기 위하여 염색과 관련된 주관적 증상과 모발의 변화에 대한 실험적 연구를 시행하였다. 동국대학교 경주 캠퍼스 재학생 80명을 대상으로 설문조사를 시행하여 염색 유 ·무 및 염색 후에 경험한 증상에 대해 설문 조사하였고, 의과대학 재학생 46명을 대상으로 피부 반응 테스트를 실시하였다. 또한 염색 전후의 모발 탄성도를 측정하였고 모발의 상태를 파악하기 위해 전자 현미경검사를 실시하였다. 설문조사 결과 염색 전에 비하여 염색 후 안구혼탁, 안구건조, 시력저하, 발진 및 접촉성 피부염, 모발손상, 모근손상 등의 증상을 더 많이 경험한다고 호소하였다(p<0.05). 모발손상과 모근손상은 헤어드라이어 사용 빈도에 따라 증가하는 것으로 조사되었다(p<0.05). 피부반응검사에서 가려움증이 가장 많은 증상이었으며 이는 여성보다는 남성에서 높은 것으로 조사되었다. 염색 전후의 모발장력은 염색 전 134.5±10.37g, 염색 128.0±30.69g, 염색 이틀 후 112.5±19.69g으로 나타났다. 염색 전후의 모발의 전자현미경 케라틴 층이 현저히 감소하고 모발이 가늘어지는 차이를 보였다. 염색은 모발손상, 모발 케라틴 손상 및 모근 손상, 발진 및 접촉성 피부반응, 안구혼탁, 안구건조, 시력 저하를 유발한다. 따라서 염색약으로 인한 손상에 대한 주의와 예방이 필요하다고 생각한다. 예방대책으로 염색 전 피부테스트를 통한 적합성 여부를 판단하는 것이 필요하며 가급적 염색을 피하는 것이 좋을 것이다. 염색약에 발암물질이 포함되어있다는 보고도 있어 염색 제조사의 철저한 실험과 염색 물질의 선별이 염색으로 인한 부작용을 최소화하는데 중요한 역할을 할 것이다. Hair coloring has became one of the most popular cosmetic activities to younger generations during last decade. However, there are few studies on the health effect of widespread use of chemical dyes. This study was conducted to study the effects of hair coloring dye on hair and other systems. We conducted a questionnaire survey of 80 persons in Kyongju campus, Dongguk University. We have done open patch skin test on 46 medical students. We also conducted scanning electron microscopy to examine the hair strength and structure before and after hair coloring process. Injury of hair and hair bulb, contact dermatitis, turbid eyes, xerophthalmia, and poor visual acuity were the main symptoms complained after hair coloring (p<0.05). Injury of hair and hair bulb were increased by frequency of hair-dryer use(p<0.05). In open patch test, pruritus was complanined by more than half of the subjects. Mean strength of hairs before and after hair coloring was as follows; 134.5 (SD 10.37)g before hair coloring, 128.0 (SD 30.69)g immediately after hair coloring, and 112.5 (SD 19.69)g after two days. The scanning electron microscopic findings of hair surface before and after hair coloring showed decreased keratin layer and thinning of the hair. Hair coloring induces injury to hair, its keratin layer, and hair bulb as well as contact dermatitis, turbid eyes, xerophthalmia, and poor visual acuity. Therefore, we think that precaution is needed in use of hair coloring dye. To prevent complications induced by hair coloring dye, it is necessary, especially to those with allergy or skin disorders, to perform skin test before action and avoid hair coloring whenever possible. Longterm health effects of hairdye should be studied and manufacturing companies should try to minimize complications induced by hair coloring dye.

On supporting full-text retrievals in XML query

Dong-Kweon Hong 한국지능시스템학회 2007 INTERNATIONAL JOURNAL of FUZZY LOGIC and INTELLIGE Vol.7 No.4

As XML becomes the standard of digital data exchange format we need to manage a lot of XML data effectively. Unlike tables in relational model XML documents are not structural. That makes it difficult to store XML documents as tables in relational model. To solve these problems there have been significant researches in relational database systems. There are two kinds of approaches: 1) One way is to decompose XML documents so that elements of XML match fields of relational tables. 2) The other one stores a whole XML document as a field of relational table. In this paper we adopted the second approach to store XML documents because sometimes it is not easy for us to decompose XML documents and in some cases their element order in documents are very meaningful. We suggest an efficient table schema to store only inverted index as tables to retrieve required data from XML data fields of relational tables and shows SQL translations that correspond to XML full-text retrievals. The functionalities of XML retrieval are based on the W3C XQuery which includes full-text retrievals. In this paper we show the superiority of our method by comparing the performances in terms of a response time and a space to store inverted index. Experiments show our approach uses less space and shows faster response times.

PSN: A Dynamic Numbering Scheme for W3C XQuery Update Facility

Dong Kweon Hong 한국지능시스템학회 2008 INTERNATIONAL JOURNAL of FUZZY LOGIC and INTELLIGE Vol.8 No.2

It is essential to maintain hierarchical information properly for efficient XML query processing. Well known approach to represent hierarchical information of XML tree is assigning a specific node number to each node of XML tree. Insertion and deletion of XML node can occur at any position in a dynamic XML tree. A dynamic numbering scheme allows us to add nodes to or delete nodes from an XML tree without relabeling or with relabeling only a few existing nodes of XML tree while executing XML query efficiently. According to W3C XQuery update facility specifications a node can be added as first or last child of the existing node in XML tree. Generating new number for last child requires referencing the number of previous last child. Getting the number of last child is very costly with previous approaches. We have developed a new dynamic numbering scheme PSN which is very effective for insertion of a node as last child. Our approach reduces the time to find last child dramatically by removing sorting of children.

On supporting full-text retrievals in XML query

Hong, Dong-Kweon Korean Institute of Intelligent Systems 2007 INTERNATIONAL JOURNAL of FUZZY LOGIC and INTELLIGE Vol.7 No.4

As XML becomes the standard of digital data exchange format we need to manage a lot of XML data effectively. Unlike tables in relational model XML documents are not structural. That makes it difficult to store XML documents as tables in relational model. To solve these problems there have been significant researches in relational database systems. There are two kinds of approaches: 1) One way is to decompose XML documents so that elements of XML match fields of relational tables. 2) The other one stores a whole XML document as a field of relational table. In this paper we adopted the second approach to store XML documents because sometimes it is not easy for us to decompose XML documents and in some cases their element order in documents are very meaningful. We suggest an efficient table schema to store only inverted index as tables to retrieve required data from XML data fields of relational tables and shows SQL translations that correspond to XML full-text retrievals. The functionalities of XML retrieval are based on the W3C XQuery which includes full-text retrievals. In this paper we show the superiority of our method by comparing the performances in terms of a response time and a space to store inverted index. Experiments show our approach uses less space and shows faster response times.

PSN: A Dynamic Numbering Scheme for W3C XQuery Update Facility

Hong, Dong-Kweon Korean Institute of Intelligent Systems 2008 INTERNATIONAL JOURNAL of FUZZY LOGIC and INTELLIGE Vol.8 No.2

It is essential to maintain hierarchical information properly for efficient XML query processing. Well known approach to represent hierarchical information of XML tree is assigning a specific node number to each node of XML tree. Insertion and deletion of XML node can occur at any position in a dynamic XML tree. A dynamic numbering scheme allows us to add nodes to or delete nodes from an XML tree without relabeling or with relabeling only a few existing nodes of XML tree while executing XML query efficiently. According to W3C XQuery update facility specifications a node can be added as first or last child of the existing node in XML tree. Generating new number for last child requires referencing the number of previous last child. Getting the number of last child is very costly with previous approaches. We have developed a new dynamic numbering scheme PSN which is very effective for insertion of a node as last child. Our approach reduces the time to find last child dramatically by removing sorting of children.

격리 포리스트를 이용한 NoSQL 데이터베이스의 구조적 이상치 탐지와 스키마 추출

홍동권(Dong-Kweon Hong) 한국지능시스템학회 2022 한국지능시스템학회논문지 Vol.32 No.3

NoSQL 데이터베이스는 스키마 제약을 강하게 요구하지 않음으로써 지속적인 스키마 변경(Schema evolution)과 다양한 구조의 데이터를 쉽게 수용할 수 있는 장점이 있다. 하지만 NoSQL 데이터베이스의 응용 프로그램의 개발과 데이터 분석 과정에서 데이터베이스에 포함된 구조적 정보의 추출과 이상치(Outlier)를 탐지하는 것은 매우 중요한 과정이다. 본 논문에서는 JSON 형식으로 표현된 NoSQL 데이터베이스의 도큐먼트(Document) 구조적 정보를 그래프로 표현하는 기존의 방식들에서 벗어나 도큐먼트의 키(Key) 집합을 활용하는 방안을 활용하였다. 키 집합은 다시 일정한 크기의 벡터로 변환되고, 트리 기반의 고립탐지 기술인 격리 포리스트(Isolation forest)의 입력으로 사용되어 컬렉션의 대표 스키마 추출과 이상치 탐지(Outlier detection)를 동시에 수행하는 기법을 제안하였다. 마지막으로 모의실험을 통하여 본 논문에서 제안한 방식이 다양한 실험 환경에서 효율적으로 스키마를 추출하고 이상치를 탐지하는 것을 확인하였다. By not requiring strong schema constraints, schema-less, NoSQL database are able to do continuous schema evolution and are cable to store data with various structure easily. However it is inevitable to extract implied schema and to detect outliers during the application development and data analysis on NoSQL database. In this paper we used set of document keys rather than building graph data structure to express structure of document with JSON format. Document keys are transformed to vector format and then the isolation forest algorithm is applied to detect outliers and to extract implicit representative schema at the same time. Finally we have shown the exactness of our approach by performing with randomly generated data and various parameters.

대체 버전을 이용한 펌 실시간 데이터베이스 동시성 제어 방법

홍동권(Hong Dong Kweon) 한국정보처리학회 1998 정보처리학회논문지 Vol.5 No.6

Firm real-time transactions on firm real-time database systems are discarded when they miss their deadlines, as there is no value to completing them after they miss their deadlines. Several approaches that exploit the semantics of firm deadlines to improve the performance of firm real-time database systems have been proposed in the literature. They are based on locking or optimistic concurrency control. The performance comparisons of the two approaches differ with systems load. In this paper, we develop a novel policy termed stop/resume deferred restart policy, and a concurrency control algorithm based on the policy (termed Alternative Version Concurrency Control). When conflicts (due to priority) occur, our algorithm maintains the immediately restarted version as well as the stopped version of a transaction in order to use one of the two to meet the firm deadline. At last we show that our policy generates serializable schedules and show that our algorithm performs better than the traditionally used method for wide ranges of the system load for firm deadline transaction.

SQL 호스트에서 동적 번호 부여 방식의 성능 평가

홍동권(Dong-Kweon Hong) 한국지능시스템학회 2009 한국지능시스템학회논문지 Vol.19 No.3

XML 일부분의 변경이 가능한 동적 XML 환경에서 XML의 검색과 변경 기능을 효율적으로 지원하기 위한 방법으로 XML 통적번호 부여 방식에 대한 연구가 활발히 진행되고 있다. 동적 번호 부여 방식은 ORDPATH, DLN과 같이 노드 번호를 부여할 때 인접 노드의 번호에 의존적인 방식과, PSN과 같이 인접한 노드의 변호에 독립적인 노드 번호를 사용하는 2가지의 방식이 있다. 본 논문은 앞의 2가지 동적 번호 부여 방식을 SQL 환경에서 비교하기 위한 환경을 구축하고, W3C XQuery의 변경 형식을 사용하여 그 성능을 비교한다. There has been many active researches on dynamic XML numbering scheme for efficient retrievals and updates of XML. There are two major approaches for dynamic numbering schemes. One approach is dependant on adjacent node numbers when they assign new number for newly inserted node. While the other approach is independent on adjacent node numbers. In this paper we explain the table schema and procedures for our experiments on an SQL host to compare the performance of the two approaches and shows W3C XQuery performance results of the two approaches on the SQL host.

XSTAR: XML 질의의 SQL 변환 알고리즘

홍동권(Dong-Kweon Hong),정민경(Min-Kyoung Jung) 한국지능시스템학회 2007 한국지능시스템학회논문지 Vol.17 No.3

XML이 다양한 분야에 널리 이용되면서 대용량의 XML을 효과적으로 관리하는 여러 가지 방법들이 연구되고 있다. 특히 지금까지 상업적, 기술적으로 성공적인 데이터 모델인 관계형 데이터베이스를 기반으로 한 여러 가지 방법들이 연구되고 있다. 본 논문은 관계형 DBMS를 사용하여 XML 질의어인 XQuery를 SQL로 변환하는 알고리즘인 XSTAR(XQuery to SQL Translation Algorithms on RDBMS)를 설계 및 구현한다. 본 연구의 XSTAR 알고리즘은 기본적인 XPath 뿐만 아니라 XQuery FLWOR 표현식, XQuery함수, 그리고 전문 검색(Fulltext 검색[8])과 관련된 몇몇 특수한 기능을 효율적으로 지원할 수 있으며, 질의의 결과 값을 XML 형태로 재생성하여 사용자에게 반환한다. 본 논문에서 제안하는 XSTAR 알고리즘은 현재 웹상에서 공개적으로 시범 운용 되고 있는 XML 문서의 관리 및 질의 처리 시스템인 XPERT(XML Query Processing Engine using Relational Technologies, http://dblab.kmu.ac.kr/project.jsp")의 질의 처리 엔진으로 사용되고 있다. There have been several researches to manipulate XML Queries efficiently since XML has been accepted in many areas. Among the many of the researches majority of them adopt relational databases as underlying systems because relational model which is used the most widely for managing large data efficiently. In this paper we develop XQuery to SQL Translation Algorithms called XST AR that can efficiently handle XPath, XQuery FLWORs with nested iteration expressions, element constructors and keywords retrieval on relational database as well as constructing XML fragments from the transformed SQL results. The entire algorithms mentioned in XSTAR have been implemented as the XQuery processor engine in XML management system, XPERT, and we can test and confirm it's prototype from "http:/dblab.kmu.ac.kr/project.jsp".