• Smart Structures and Systems
• /
• 제6권5_6호
• /
• pp.561-578
• /
• 2010

This study proposes a multi-level damage localization strategy to achieve an effective damage detection system for civil infrastructure systems based on wireless sensors. The proposed system is designed for use of distributed computation in a wireless sensor network (WSN). Modal identification is achieved using the frequency-domain decomposition (FDD) method and the peak-picking technique. The ASH (angle-between-string-and-horizon) and AS (axial strain) flexibility-based methods are employed for identifying and localizing damage. Fundamentally, the multi-level damage localization strategy does not activate all of the sensor nodes in the network at once. Instead, relatively few sensors are used to perform coarse-grained damage localization; if damage is detected, only those sensors in the potentially damaged regions are incrementally added to the network to perform finer-grained damage localization. In this way, many nodes are able to remain asleep for part or all of the multi-level interrogations, and thus the total energy cost is reduced considerably. In addition, a novel distributed computing strategy is also proposed to reduce the energy consumed in a sensor node, which distributes modal identification and damage detection tasks across a WSN and only allows small amount of useful intermediate results to be transmitted wirelessly. Computations are first performed on each leaf node independently, and the aggregated information is transmitted to one cluster head in each cluster. A second stage of computations are performed on each cluster head, and the identified operational deflection shapes and natural frequencies are transmitted to the base station of the WSN. The damage indicators are extracted at the base station. The proposed strategy yields a WSN-based SHM system which can effectively and automatically identify and localize damage, and is efficient in energy usage. The proposed strategy is validated using two illustrative numerical simulations and experimental validation is performed using a cantilevered beam.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 2004년도 ICCAS
• /
• pp.857-862
• /
• 2004

This paper analyzes properties of the recently developed nonlinear optimization method, Dynamic Encoding Algorithm for Searches (DEAS) [1]. DEAS locates local minima with binary strings (or binary matrices for multi-dimensional problems) by iterating the two operators; bisectional search (BSS) and unidirectional search (UDS). BSS increases binary strings by one digit (i.e., zero or one), while UDS performs increment or decrement to binary strings with no change of string length. Owing to these search routines, DEAS retains the optimization capability that combines the special features of several conventional optimization methods. In this paper, a special feature of BSS and UDS in DEAS is analyzed. In addition, a effective global search strategy is established by using information of DEAS. Effectiveness of the proposed global search strategy is validated through the well-known benchmark functions.

• 대한전자공학회:학술대회논문집
• /
• 대한전자공학회 2003년도 컴퓨터소사이어티 추계학술대회논문집
• /
• pp.129-132
• /
• 2003

The metathesaurus(UMLS, 2003AA edition) supports multi language and includes 875, 233 concepts, 2, 146, 897 concept names. It is impossible for PubMed or NLM serve searching of the metatheaurus to retrieval using a query that is not to be text, a fault sentence structure or a part of concept name. That means the user notice correctly suitable medical words in order to get correct answer, otherwise she or he can't find information that they want to find I propose that the method of searching unified medical language system using automatic modified a query for problem that I mentioned. This method use dictionary that is standard for automation of modified query gauge similarity between query and dictionary using string comparison algorithm. And then, the tested term converse the form of metathesaurus for optimized result. For the evaluation of method, I select some query and I contrast NLM method that renewed Aug. 2003.

• 전력전자학회:학술대회논문집
• /
• 전력전자학회 2010년도 추계학술대회
• /
• pp.34-35
• /
• 2010

본 논문에서는 50 ㎾ 인터리브드 멀티스트링 태양광 인버터의 제어기 설계방법에 대하여 해석하여 보았다. 개발된 태양광 인버터는 5대의 10㎾ 인터리브드 DC-DC 컨버터와 50㎾ 인버터 그리고 L-C-L 필터로 구성되어 있으며 각각의 컨버터와 인버터에는 제안된 제어기법들이 적용되어 있다. 프로토타입 태양광 PCS(Power conditioning system)를 설계 제작하여 각각의 제안된 제어 알고리즘을 실험을 통해 확인하고 검증하였다.

• 전력전자학회논문지
• /
• 제26권1호
• /
• pp.9-15
• /
• 2021

In multi-string light-emitting diode (LED) driver system, current balancing is crucial because the brightness of LED is directly related to its forward current. This paper presents a novel LED current balancing topology using current-fed Z-source converter. With the proposed structure, currents flowing through two LED strings are automatically balanced owing to the charge-balance condition on capacitors. Operation of the proposed converter is simple and the proposed converter uses only one active switch and one diode. Moreover, low-side gate driving can be used to operate the active switch. To verify the operation of the proposed LED current balancing converter, a prototype is built and tested with different numbers of LEDs.

• 정보처리학회논문지B
• /
• 제11B권7호
• /
• pp.875-884
• /
• 2004

UCS(=ISO/BC 10646, =Unicode)는 국제화에 따라 앞으로 점점 더 많이 쓰게 될 것이고, 일단 정착되고 나면 한참 동안 쓸 것으로 예상하고 있다. 하지만, UCS로는 남한과 북한의 같은 글자를 쓰면서도 다른 사전 순서로 쓰는 상황을 해결할 수 없다. 국제 표준 ISO/IEC 14651:2000(International String Ordering)은 여러 나라 글자계(script)가 섞여 있을 때, 모든 글자의 차례를 정하고 간추리는 틀에 관한 표준이다. ISO/IEC 14651을 이용하면 간추리는 차례가 공통 틀 표(Common Template Table)에 들어 있기 때문에 글자의 간추리는 차례를 쉽게 바꿀 수 있으며, 남한과 북한의 가나다 차례를 통일하지 않고 글자 순서가 다른 문제를 해결할 수 있다. ISO/IEC 14651 관련 함수는 리눅스와 솔라리스, FreeBSD와 같은 유닉스 기반 운영체제의 최신 라이브러리에 포함되어 있다. 본 논문에서는 북쪽의 한글 가나다 차례를 남쪽에서 활용할 수 있도록 하기 위해서 북쪽의 한글 가나다 차례를 포함하는 북쪽 로캘을 리눅스 시스템에서 만들고, 입력된 문자열(=글자떼)을 남쪽 혹은 북쪽의 한글 가나다 차례에 따라 간추리기 할 수 있는 프로그램을 개발하였다.

• 대한수학회보
• /
• 제46권4호
• /
• pp.743-769
• /
• 2009

An ID-based DNF signature scheme is an ID-based signature scheme with an access structure which is expressed as a disjunctive normal form (DNF) with literals of signer identities. ID-based DNF signature schemes are useful to achieve not only signer-privacy but also a multi-user access control. In this paper, we formally define a notion of a (non-interactive) ID-based DNF signature and propose the first noninteractive ID-based DNF signature schemes that are secure under the computational Diffie-Hellman and subgroup decision assumptions. Our first scheme uses random oracles, and our second one is designed without random oracles. To construct the second one, we use a novel technique that converts a non-interactive witness indistinguishable proof system of encryption of one bit into a corresponding proof system of encryption of a bit-string. This technique may be of independent interest. The second scheme straightforwardly yields the first ID-based ring signature that achieves anonymity against full key exposure without random oracles. We finally present two extensions of the proposed ID-based DNF signature schemes to support multiple KGCs and different messages.

• International Journal of Fuzzy Logic and Intelligent Systems
• /
• 제12권4호
• /
• pp.277-284
• /
• 2012

Named entity recognition (NER) technique can play a crucial role in extracting information from the web. While NER systems with relatively high performances have been developed based on careful manipulation of terms with a statistical model, term mismatches often degrade the performance of such systems because the strings of all the candidate entities are not known a priori. Despite the importance of lexical-level term mismatches for NER systems, however, most NER approaches developed to date utilize only the term string itself and simple term-level features, and do not exploit the semantic features of terms which can handle the variations of terms effectively. As a solution to this problem, here we propose to match the semantic concepts of term units in restaurant named entities (NEs), where these units are automatically generated from multiple resolutions of a semantic tree. As a test experiment, we applied our restaurant NER scheme to 49,153 nouns in Korean restaurant web pages. Our scheme achieved an average accuracy of 87.89% when applied to test data, which was considerably better than the 78.70% accuracy obtained using the baseline system.

• 대한전자공학회:학술대회논문집
• /
• 대한전자공학회 2006년도 하계종합학술대회
• /
• pp.857-858
• /
• 2006

Estrangement hierarchical by bipolarization is deepened and time space that social welfare by graying corresponds great so. Specially, is real condition that indifference by patient's increase which is solitary life string is come to involve by social problem. Together, Jaetaek bone fracture patient's ratio is zooming. Domestic BT technology, medical treatment solution technology offer more important role than role assistance enemy of modern technology and utilize by creative technology can . Specially, if apply supersonic waves in bone fracture treatment, there is treatise data that can reduce bone fracture treatment period of bone that bone does not stick well about 40%. Supersonic waves operation frequency used on both end because do 1m Hz, 1.3mHz, supersonic waves origination that have 1.5mHz's Piezo-ceramic crystal tranducer material each 4 premature senilitys in this research, and outside diameter according to impedance and Phase d used Gakgak4mm, 5.4mm, Dukke0.5mm, transformer deuce of length 70mm. Manufactured, and investigated supersonic waves distribution chart by capacity 50m W. Supersonic waves used by diagnosis mainly but is seen to become convenient medical treatment mounting in bone fracture patient's treatment if supplement clinically. If supplement system furthermore, is going to apply to osteoporosis patient, and this research tried to design poetic theme width directly and study rain standardization special quality and approach basic form because do modelling.

• 대한기계학회논문집A
• /
• 제26권4호
• /
• pp.644-652
• /
• 2002

Increasing demands for Electric Resistance Welded pipes of high quality with thick wall require c lose investigations in edge deformation by slitting, strip deformation during break down farming, and difference of circumferential length. In order to obtain good quality of a welding zone, it is necessary to predict the edge shape of the initial strip. The modeling of the multi-pass thick tube roll forming process with rigid plastic finite element method ultra the edge shape prediction of an initial strip with 2nd-degree polynomial regression method are presented. Edge shapes of initial strip have been analyzed by the finite element method and designed by the regression method to satisfy the requirements in target fin pass. It is concluded that the proposed edge design method results in optimal edge shapes sat string the design requirements.