• 한국CDE학회논문집
• /
• 제3권3호
• /
• pp.177-182
• /
• 1998

The computer related techniques have been developed rapidly in the field of metal removal industry. The electronic catalog for mechanical elements is one of such developments realized in recent years. As the emergence of the electronic catalogs in the 90s, it breaks the restriction of the traditional catalog and becomes a helpful and efficient tool in the field. In this paper, we develop an electronic catalog for the cutting tools of the Korea Tungsten Co. Ltd. The catalog consists of three parts: a preprocessor for tool selection, a database for tool, and a postprocessor for search result. A preprocessor for tool selection is developed under a user-friendly consideration. A database for tool consists of milling, drilling, and reaming tools with a list of cutters, inserts, and components. A postprocessor for search result consists of weight, dimension. drawing, product order number etc. of the tools. It also suggests the optimized cutting condition of the selected tool using a neural network technique which is done by an independent research group.

• 전자공학회논문지B
• /
• 제30B권11호
• /
• pp.84-92
• /
• 1993

Calibration of Engine models is a painstaking process but very important for successful application to automotive industry problems. A combined heuristic and machine learning approach has therefore been adopted to improve the efficiency of model calibration. We developed an intelligent calibration program called ICALIB. It has been used on a daily basis for engine model applications, and has reduced the time required for model calibrations from many hours to a few minutes on average. In this paper, we describe the heuristic control strategies employed in ICALIB such as a hill-climbing search based on a state distance estimation function, incremental problem solution refinement by using a dynamic tolerance window, and calibration target parameter ordering for guiding the search. In addition, we present the application of amachine learning program called GID3*for automatic acquisition of heuristic rules for ordering target parameters.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2007년도 제38회 하계학술대회
• /
• pp.1665-1667
• /
• 2007

Recently, retrieval of various video data has become an important issue as more and more multimedia content services are being provided. To effectively deal with video data, a semantic-based retrieval scheme that allows for processing diverse user queries and saving them on the database is required. In this regard, this paper proposes a semantic-based video retrieval system that allows the user to search diverse meanings of video data for electrical safetyrelated educational purposes by means of automatic annotation processing. If the user inputs a keyword to search video data for electrical safety-related educational purposes, the mobile agent of the proposed system extracts the features of the video data that are afterwards learned in a continuous manner, and detailed information on electrical safety education is saved on the database. The proposed system is designed to enhance video data retrieval efficiency for electrical safety-related educational purposes.

• 한국멀티미디어학회논문지
• /
• 제18권1호
• /
• pp.52-64
• /
• 2015

Recently, as the quality of life has been improving, search items in the area of entertainment represent an increasing share of the total usage of Internet portal sites. Information retrieval in the entertainment area is mainly depending on keywords that users are inputting, and the results of information retrieval are the contents that contain those keywords. In this paper, we propose a search method that takes natural language inputs and retrieves the database pertaining to entertainment. The main components of our study are the simple Korean morphological analyzer using case particle information, predicate-oriented token generation, standardized pattern generation coherent to tokens, and automatic generation of the corresponding SQL queries. We also propose an efficient retrieval system that searches the most relevant results from the database in terms of natural language querying, especially in the restricted domain of music, and shows the effectiveness of our system.

• 산업경영시스템학회지
• /
• 제12권19호
• /
• pp.73-78
• /
• 1989

This paper concerns the production model that the Automatic Guided Vehicles(AGVs) is used as transporters in assembly line. The model suggests that assembly parts may inter the beginning of the line in multiple units instead entering one unit at a time. Costs are occured in proportion to the number of vehicle on the line and job flow time. Here, the objective of this model is to determine the number of vehicle to minimize the total cost for M products production. Theoretical results are proved which lead to the development of algorithm for solution search. The solution search procedure is illustrated by a numerical example.

• 한국도서관정보학회지
• /
• 제51권2호
• /
• pp.355-379
• /
• 2020

학교도서관업무지원시스템(DLS)은 학교도서관 자료에 대한 핵심적 접근 도구이다. 본 연구의 목적은 DLS에서의 학생들의 정보검색행태 분석을 통해 학교도서관 자료 접근성 향상 방안을 탐색적으로 고찰하는 데 있다. 이에 학교도서관에서 DLS 검색을 시도하는 학생 42명을 대상으로 DLS 검색과정을 녹화하고 정보요구 전반에 대한 검색-전 질문지와 검색과정과 결과에 대한 검색-후 질문지를 통해 자료를 수집하였다. 분석결과, 평소 DLS 이용의 주목적이 단순 여가 독서인 경우, 정보요구가 상대적으로 모호한 경우, 그리고 검색과정에서 복잡한 상황을 겪는 경우 등에서 검색 성공률과 검색 만족도가 낮게 나타났다. 검색 만족도는 검색시간 충분성에 대한 만족도가 가장 높게, 검색 결과 만족도가 가장 낮게 나타났다. 기타 의견으로 정보 통합 검색, 관련 자료추천, 소장 위치 출력, 모바일 앱을 통한 음성 인식, 검색 실수 자동 교정 기능 등 요구가 있었다. 이를 통해 다음과 같이 제언할 수 있다. 첫째, 진학 및 진로정보 제공에 대한 교육 수요자의 요구를 반영하여 DLS 역시 진학 및 진로정보를 제공하는 기능을 보완해야 한다. 둘째, 일반적 정보 검색 시스템 수준으로의 DLS 기능 개선이 필수적이다. 셋째, 학교도서관 현장 인력과 DLS 관리 당국 간 긴밀한 협력을 위한 인프라가 구축되어야 한다.

• 제어로봇시스템학회논문지
• /
• 제17권8호
• /
• pp.747-752
• /
• 2011

HMMs (Hidden Markov Models) are widely used for biological signal, such as EEG (electroencephalogram) sequence, analysis because of their ability to incorporate sequential information in their structure. A recent trends of research are going after the biological interpretable HMMs, and we need to control the complexity of the HMM so that it has good generalization performance. So, an automatic means of optimizing the structure of HMMs would be highly desirable. In this paper, we described a procedure of classification of motor imagery EEG signals using HMM. The motor imagery related EEG signals recorded from subjects performing left, right hand and foots motor imagery. And the proposed a method that was focus on the validation of the HSA (Harmony Search Algorithm) based optimization for HMM. Harmony search algorithm is sufficiently adaptable to allow incorporation of other techniques. A HMM training strategy using HSA is proposed, and it is tested on finding optimized structure for the pattern recognition of EEG sequence. The proposed HSA-HMM can performs global searching without initial parameter setting, local optima, and solution divergence.

• Journal of Electrical Engineering and Technology
• /
• 제7권1호
• /
• pp.109-114
• /
• 2012

In this paper, we utilize training strategy of hidden Markov model (HMM) to use in versatile issues such as classification of time-series sequential data such as electric transient disturbance problem in power system. For this, an automatic means of optimizing HMMs would be highly desirable, but it raises important issues: model interpretation and complexity control. With this in mind, we explore the possibility of using genetic algorithm (GA) and harmony search (HS) algorithm for optimizing the HMM. GA is flexible to allow incorporating other methods, such as Baum-Welch, within their cycle. Furthermore, operators that alter the structure of HMMs can be designed to simple structures. HS algorithm with parameter-setting free technique is proper for optimizing the parameters of HMM. HS algorithm is flexible so as to allow the elimination of requiring tedious parameter assigning efforts. In this paper, a sequential data analysis simulation is illustrated, and the optimized-HMMs are evaluated. The optimized HMM was capable of classifying a sequential data set for testing compared with the normal HMM.

• Structural Engineering and Mechanics
• /
• 제12권6호
• /
• pp.685-698
• /
• 2001

In this paper, a general method for the automatic search for Strut-and-Tie (S&T) models representative of possible resistant mechanisms in reinforced concrete elements is proposed. The representativeness criterion here adopted is inspired to the principle of minimum strain energy and requires the consistency of the model with a reference stress field. In particular, a highly indeterminate pin-jointed framework of a given layout is generated within the assigned geometry of the concrete element and an optimum truss is found by the minimisation of a suitable objective function. Such a function allows us to search the optimum truss according to a reference stress field deduced through a F.E.A. and assumed as representative of the given continuum. The theoretical principles and the mathematical formulation of the method are firstly explained; the search for a S&T model suitable for the design of a deep beam shows the method capability in handling the reference stress path. Finally, since the analysis may consider the structure as linear-elastic or cracked and non-linear in both the component materials, it is shown how the proposed procedure allows us to verify the possibilities of activation of the design model, oriented to the serviceability condition and deduced in the linear elastic field, by following the evolution of the resistant mechanisms in the cracked non-linear field up to the structural failure.

• 한국수자원학회:학술대회논문집
• /
• 한국수자원학회 2002년도 학술발표회 논문집(II)
• /
• pp.1316-1321
• /
• 2002

일반적으로 강우-유출모형은 lumped model과 distributed model로 크게 구분될 수 있으며, 우리나라에서는 이중 비교적 부족한 자료를 이용하여도 개략적 모의가 가능한 전자를 널리 사용하고 있다. 본 연구에서는 이러한 모형들의 매개변수를 보정하는 방법에 관해 연구하였다. 일반적으로 모형의 보정 방법에는 크게 시행오차에 의한 수동보정(manual calibration) 방법과 최적화 기법에 의한 자동보정(automatic calibration) 방법으로 나눌 수 있다. 수동보정 방법은 모형 수행결과를 수문곡선의 시각적 비교에 의해 관측치와 비교하여 모형 운영자의 주관적인 판단하에 조정하는 기법이며, 자동보정 방법은 최적화 기법을 이용8하여 특정한 산정기준(estimation criteria)을 최대 또는 최소화시켜 모형의 매개변수를 결정하는 방법이다. 이러한 최적화기법은 일반적으로 직접탐색법과 경사법으로 구분할 수 있다. 경사법은 수렴속도가 빠르지만 편미분에 의해 방향을 찾아가는 방법으로 편도함수가 필요하므로 수문모형에는 적용하기가 힘들므로 적합하지 않다. 그러나, 보다 많은 컴퓨터 수행시간을 필요로 하는 직접탐색법의 경우 수렴속도는 느리지만, 편도함수를 필요치 않으므로 수문모형의 최적화 기법으로 적합하다고 할 수 있다. 직접탐색법에는 simplex-search 법, 패턴인식(pattern-search)법, rotating-direction 법, brent 법 등이 있으며, 본 연구에서는 직접탐색법의 일종인 패턴인식(pattern -search)법을 이용하여 매개변수 최적화 과정을 모의하였다. 이러한 매개변수 보정모형을 구성한 후 이를 가장 보편적으로 사용되고 있는 유출모형인 각종 단위도법들을 결합하는 모형을 구성하였다. 또한 구성된 모형을 시범유역에 적용하여 나온 결과를 HEC-1에서 적용되고 있는 단일변량 증감법과 같은 최적화 기법을 이용한 결과와 비교·분석을 실시하였다. 본 모형을 활용하여 강우-유출 모형의 매개변수를 지속적으로 산정하고 일반화할 경우 임의의 유역의 수문기상학적 특성에 부합한 매개변수를 정량화 시킬 수 있었다.