• Journal of Intelligence and Information Systems
• /
• v.10 no.2
• /
• pp.111-131
• /
• 2004

Software change is an essential operation for software evolution. To maintain the system competently, managers as well as developers must be able to understand the structure of the system but the structure of software is hidden to the developers and managers who need to change it. In this paper, we present a system (OntCIA) for supporting change impact analysis for rating and billing domain based on the semantic web technology. The basic idea of OntCIA is to build a domain knowledge base using an OWL ontology and RDF to implement change impact analysis system that would support the managers and software developers in finding out information about structure of large software system. OntCIA allows users to incrementally build an ontology in rating and billing domain and provides useful information in response to user queries concerning the code, such as, for example 'Find the modules which have a role for confirming new subscription'. The strengths of OntCIA are its architecture for easy maintenance as well as semantic indexing by automatic reasoning.

• Journal of Internet Computing and Services
• /
• v.13 no.3
• /
• pp.23-30
• /
• 2012

In order to show the gap between theory and practice, this paper first gives some experimental results for theoretical and real neighbor sets on a test-bed sensor network. The results prove that existing management protocols (e.g., duty-cycling, routing or aggregation) based on the theoretical communication radius cannot achieve their original goal, efficiency. In this paper, we present a practical duty-cycling mechanism based on the real neighbor set, allowing for energy-efficiency. It also guarantees to suppress duplicated transmissions of sensing values with similarity within a specific threshold in each zone (i.e., a portion of intended divided network). Simulation results performed with a set of real sensor data show that our mechanism increases the network life time while guaranteeing the transmission of necessary sensing values.

• KIISE Transactions on Computing Practices
• /
• v.23 no.2
• /
• pp.116-121
• /
• 2017

In wireless sensor networks, the multipath prefers energy efficient routing method due to the characteristic of low-power sensor which uses geographic method to transmit data packet through information of the neighbor nodes. However, when multipath meets the routing fail area called hole area, path overlap problem can occur, resulting in failed maintenance of disjoint multipath. To solve this problem, multipath research studies have been performed to exploit the modeling and detouring method in routing fail area by keeping the disjoint multipath. However, in an energy point of view, additional method like modeling can lead to a lot of energy consumption of sensor node. Moreover, lots of energy consumption of sensor node can shorten the life span of sensor network. In this study, we proposed an energy efficient geographic routing by keeping the disjoint multipath in routing fail area. The proposed scheme exploited the face routing using the geographic recovery method without additional method like modeling.

• The Journal of the Korean life insurance medical association
• /
• v.22
• /
• pp.121-137
• /
• 2003

현행 생명보험업계는 중복가입계약에 대한 정보교환제도를 시행함으로써 잠재적 위험에 대한 위험평가를 하고는 있으나 실제 언더라이팅 과정에서는 효율적인 활용을 못하고 있다. 따라서 언더라이팅 실무 입장에서 현행 정보교환제도의 문제점을 파악하고 각 보험회사가 취할 수 있는 효율적인 대응방안을 제시할 필요성이 대두되고 있다. 현행 정보교환제도의 문제점을 크게 몇가지로 나눌 수 있다. - 교환기준에 미달하는 다수의 계약건을 가입한 경우 위험평가 불가 - 위험평가상 고지의무에 충실한 계약자의 상대적 불리 - 정해진 기준과 다른 임의적 기준적용 등 선별적 자료교환으로 위험선택에서 배제된 잠재적 위험들의 계속적인 계약 및 지급 등 역선택 방조기능 - 실시간 반영된 정보부재 및 교환된 자료만으로 one-stop 위험평가를 할 수 없는 어려움 내재 - 정보교환에 대한 전체적 참여노력 부족 및 자기정보에 대한 방어와 자체 활용 이런 문제점들을 인식하고 이에 대한 효율적 대응방안을 제시해 본다. - 언더라이팅 측면에서 판매채널 다변화, 업무겸업화 둥 대외 환경변화에 따른 위험분석 및 평가, 위험분산을 위한 multi-player로서의 언더라이터 양성 필요 - 지급, 조사건의 분석 및 통계화 등 feed back 기능 강화통한 언더라이팅 활용 - 방문진단 통한 적부기능 활용 또는 모집자 사정평점제 등 언더라이팅 과정에서 활용할 수 있는 위험평가 자료축적 - 영업환경적 측면에서 고보장 상품의 경쟁적인 개발제한 - 정보교환제도 측면에서 정보교환 기준 변경 및 교환내용 추가 및 공동의 계약인수 guideline 필요 - 진단거절체, 표준미달체, 사절체 등 새로운 정보교환의 추진 필요 - 종합적인 피보험자의 정보를 획득할 수 있는 피보험자 종합정보의 데이터 구축 및 활용 효율적인 위험관리 외에도 각 보험회사별로 역선택 위험에 대한 심각성을 인식하고 업계간 정보교환에 적극적인 참여와 노력이 필요하며 잠재적 위험평가를 하는데 있어 계약자에게는 객관적 근거없이 불편을 갖지 않도록 언더라이팅 서비스하는 것 또한 중요하다. 지속적인 피보험자의 위험통계축적으로 잠재위험에 대한 보다 객관화된 위험평가를 할 수 있는 언더라이팅 기법을 체득함으로써 언더라이팅 경쟁력을 갖을 수 있다.

• Journal of Korea Multimedia Society
• /
• v.15 no.10
• /
• pp.1247-1256
• /
• 2012

There are many filter based image processing algorithms and they usually require a huge amount of computations and memory accesses making it hard to attain a real-time performance, expecially in embedded applications. In this paper, we propose a pipelined hardware structure of the filter based face detection algorithm to show that the real time performance can be achieved by hardware design. In our design, the whole computation is divided into three pipeline stages: resizing the image (Resize), Transforming the image (ICT), and finding candidate area (Find Candidate). Each stage is optimized by considering the parallelism of the computation to reduce the number of cycles and utilizing the line memory to minimize the memory accesses. The resulting hardware uses 507 KB internal SRAM and occupies 9,039 LUTs when synthesized and configured on Xilinx Virtex5LX330 FPGA. It can operate at maximum 165MHz clock, giving the performance of 108 frame/sec, while detecting up to 20 faces.

• KIISE Transactions on Computing Practices
• /
• v.24 no.3
• /
• pp.129-137
• /
• 2018

NVMe(Non-Volatile Memory Express) SSD(Solid State Drive) is a high-performance storage that makes use of flash memory as a storage cell, PCIe as an interface and NVMe as a protocol on the interface. It supports multiple I/O queues which makes it feasible to process parallel-I/Os on multi-core environments and to provide higher bandwidth than SATA SSDs. Hence, NVMe SSD is considered as a next generation-storage for data-center and cloud computing system. However, in the virtualization system, the performance of NVMe SSD is not fully utilized due to the bottleneck of the software I/O stack. Especially, when it uses I/O stack of the hypervisor or the host operating system like Xen and KVM, I/O performance degrades seriously due to doubled-I/O stack between host and virtual machine. In this paper, we propose a new I/O engine, called Direct-AIO (Direct-Asynchronous I/O) engine, that can access NVMe SSD directly for I/O performance improvements on QEMU emulator. We develop our proposed I/O engine and analyze I/O performance differences between the existed I/O engine and Direct-AIO engine.

• The Journal of the Korea Contents Association
• /
• v.8 no.1
• /
• pp.203-211
• /
• 2008

Due to the advent of presumer and digital production of moving picture, a lot of UCC has been generated by editing the previous moving pictures in various way. It causes a lot of problems on copyright, duplication, and content. In reorganizing the contents, it is necessary to increase productivity and reusability by managing production pipeline systematically through the standardization of moving picture content. For this purpose, we try to develop the moving picture content management system that can manage all kinds of information on the production pipeline, based on SCORM of e-learning by considering production, publication and re-editing. Using the meta-data of content object, user and producer can easily search and reuse the contents. Hence, they can choose the contents object according to their preference and reproduce their own creative UCC by reorganizing and packaging the selected objects. The management of copyright by the unit of scene would solve the problem of copyright. The sequencing technique of SCORM as an interactive storytelling method makes it possible to produce individual contents by user's preference.

• The KIPS Transactions:PartD
• /
• v.11D no.5
• /
• pp.1021-1030
• /
• 2004

When any data-centric XML documents are stored and managed in RDBMS, schema extracting from XML Schema is an imminent problem. Furthermore, when they are stored in partitioned way on created table, lots of null values will be produced and/or be increased cost for join, so we need a solution to solve these problems. This paper proposes a Schema Hybrid Inlining technique to generate relational schema of XML documents. The suggested technique creates a relational schema based on the XML Schema graph. Also, the technique expands the legacy Inlining method by manual and heuristic processing table generation method of cardinality and in-degree. Then, an ancestor node, terminal node, and creating a new table on the derived relation in this technique. DTD-dependent storage method uses partitioned storing and relation path element information reformed structured-searching method to reduce joining operation cost that is a weak point of it.

• The Transactions of the Korea Information Processing Society
• /
• v.4 no.5
• /
• pp.1231-1242
• /
• 1997

This paper deals with an IP mukticast protocol in support of host mobility. Most of the previous multicast schemes have utilized an underlying logical strucuture of network topology,in order to provide a certain degree of order and predictability.On the other hand,mobility implies that a host location relaative to the rest of the net-work changes with time;the physical connectivity of the entire network is thus modified as move.In this case.some multicast datagrams nay not delivered properly,or may delivered twice or more,to a mobile host because the destinations will keep moving whlist datagrams are dekivered with different time delay.This paper first describes the relation between host mobility and multicast, by exploring the possible interactions,and presents a multicast scheme in support of Internet host mobility.A revised scheme is then proposed to adapt the multicast semantic and to optimize the communication overhead.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.37B no.9
• /
• pp.795-805
• /
• 2012

This paper proposes an algorithm and a hardware architecture for a broadcast communication which has the worst bottleneck among multiprocessor using distributed memory architectures. In conventional system, The pipelined broadcast algorithm is an algorithm which takes advantage of maximum bandwidth of communication bus. But unnecessary synchronization process are repeated, because the pipelined broadcast sends the data divided into many parts. In this paper, the MPI unit for pipeline chain algorithm based on circuit switching removing the redundancy of synchronization process was designed, the proposed architecture was evaluated by modeling it with systemC. Consequently, the performance of the proposed architecture was highly improved for broadcast communication up to 3.3 times that of systems using conventional pipelined broadcast algorithm, it can almost take advantage of the maximum bandwidth of transmission bus. Then, it was implemented with VerilogHDL, synthesized with TSMC 0.18um library and implemented into a chip. The area of synthesis results occupied 4,700 gates(2 input NAND gate) and utilization of total area is 2.4%. The proposed architecture achieves improvement in total performance of MPSoC occupying relatively small area.