• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2006.11a
• /
• pp.484-487
• /
• 2006

In this paper, linear ultrasonic actuators are designed using two dimensional motions of a PMW-PT piezoelectric plate. By equalizing the natural frequencies of longitudinal and transverse vibration modes in the cantilever structure, the ultrasonic motion of the combined vibration modes are generated. We have designed two different PMN-PT actuators: one uses a tip attached on the edge of the actuator and it drives the object in the perpendicular direction of the tip. In other model, the actuator plate moves itself through stationary guides. Prototypes of the two models are manufactured and experiments results are compared to the theoretical and numerical results. The effects of structural characteristics and the friction force existing between the actuator tip and the moving object are considered. Experiments show the possibility of small size ultrasonic linear motors which can be applicable to small form factor information storage and phone camera actuators.

• IE interfaces
• /
• v.17 no.2
• /
• pp.226-232
• /
• 2004

In shipbuilding area, data sharing is one of the crucial issues. Recently, for collaborative design, ship structural CAD systems adopt the database as its primary storage. Database is useful to deal with the large amount of design information among the heterogeneous design department and design stage. To make the database-based CAD system object-oriented database(OODB) and object-relational database(ORDB) can be used. It is important to select proper database because the CAD system performance mainly depends on access performance of database. In this research, using prototype CAD system from other research, access performance of OODB and ORDB form CAD system was evaluated. STEP application protocol was used as the database schema and experiment was made in query by property and query by region. The results give some idea of how to choose the database for CAD systems.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.18 no.8
• /
• pp.1176-1189
• /
• 1993

This paper presents the Multiple Keyword Retrieval Method under the Object-Oriented Multimedia Database Model. The multiple keyword registration and retrieval algorithms are developed to reduce the partial matching problem in multimedia data retrieval. For this, proper storage structures of the lookup tables are designed. And also, in order to maintain the constant retrieval time, media data files are organized with B+ tree structure.

• Proceedings of the IEEK Conference
• /
• 2008.06a
• /
• pp.1039-1040
• /
• 2008

Multi-resolution approach to object detection wherein all entities including the partial information and background knowledge are modeled in set-theoretic terms whereby associated processing are formulated via set-theoretic operations is investigated. The generic set-theoretic paradigm is then applied to particular problems of detecting malfunctions in semiconductor fabrication process wherein the computational- and storage- efficiencies as enabled by morphological signal processing further coupled with flexibilities enabled by multi-resolution approach leads to a scalable paradigm in which the desired performance can be obtained on-demand fashion.

• Journal of information and communication convergence engineering
• /
• v.21 no.1
• /
• pp.24-31
• /
• 2023

The solid-state drive (SSD) possesses higher input and output speeds, more resistance to physical shock, and lower latency compared with regular hard disks; hence, it is an increasingly popular storage device. However, tiny components on an internal printed circuit board (PCB) hinder the manual detection of malfunctioning components. With the rapid development of artificial intelligence technologies, automatic detection of components through convolutional neural networks (CNN) can provide a sound solution for this area. This study proposes applying the YOLOv5 model to SSD PCB component detection, which is the first step in detecting defective components. It achieves pioneering state-of-the-art results on the SSD PCB dataset. Contrast experiments are conducted with YOLOX, a neck-and-neck model with YOLOv5; evidently, YOLOv5 obtains an mAP@0.5 of 99.0%, essentially outperforming YOLOX. These experiments prove that the YOLOv5 model is effective for tiny object detection and can be used to study the second step of detecting defective components in the future.

• Proceedings of the Korean Society of Computer Information Conference
• /
• 2022.07a
• /
• pp.105-106
• /
• 2022

본 논문에서는 YOLO v3 라이브러리를 이용하여 CCTV 저장 공간을 확보하는 모델을 제안한다. 사회안전망을 구축하기 위해 CCTV 설치가 확대되고, 그에 따라 많은 CCTV가 운영됨에 있어 저장 공간이 부족한 현상이 늘고 있다. 이에 본 논문에서는 학습된 데이터 셋을 활용하여 CCTV 영상파일의 프레임을 확인하여 움직임이 있는 객체가 있는지 판단하고, 움직임이 감지되는 프레임 영상을 저장한다. 제안 모델을 적용하여 테스트 한 결과 원본 데이터 크기보다 결과 데이터 크기가 85% 감소됨을 확인하였다. 인적이 드문 곳에 설치된 CCTV의 경우 제안 모델을 적용할 경우, 저장 공간의 관리 및 운영이 용이해질 것으로 기대할 수 있다.

• Smart Media Journal
• /
• v.13 no.4
• /
• pp.65-75
• /
• 2024

This paper proposes a new approach to video surveillance systems, which have become essential components in modern urban management. By utilizing blockchain and IPFS, it enhances data integrity and privacy protection. Additionally, anomaly detection and automatic video storage are enabled through object detection technology, thus improving urban safety and security. This integrated approach serves as an efficient management methodology for surveillance systems, providing city administrators and citizens with a safer and more effective monitoring environment.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.24 no.2
• /
• pp.35-40
• /
• 2024

In this paper, we validate the practicality of the OnePIC app implemented in the previous study by analyzing the execution and storage performance. The OnePIC app is a camera app that allows you to get a photo with a desired focus after taking photos focused on various places. To evaluate performance, we analyzed distance focus shooting time and object focus shooting time in detail. The performance evaluation was measured on actual smartphone. Distance focus shooting time for 5 photos was around 0.84 seconds, the object detection time was around 0.19 seconds regardless of the number of objects and object focus shooting time for 5 photos was around 4.84 seconds. When we compared the size of a single All-in-JPEG file that stores multi-focus photos to the size of the JPEG files stored individually, there was no significant benefit in storage space because the All-in-JPEG file size was subtly reduced. However, All-in-JPEG has the great advantage of managing multi-focus photos. Finally, we conclude that the OnePIC app is practical in terms of shooting time, photo storage size, and management.

• The Journal of Information Technology and Database
• /
• v.7 no.2
• /
• pp.17-32
• /
• 2000

As XML emerging as the Internet electronic document language standard of the next generation, the number of XML documents which contain vast amount of Information is increasing substantially through the transformation of existing documents to XML documents or the appearance of new XML documents. Consequently, XML document retrieval system becomes extremely essential for searching through a large quantity of XML documents that are storied in and managed by DBMS. In this paper we describe the design and implementation of BADA-IV/XML query processor that supports content-based, structure-based and attribute-based retrieval. We design XML query language based upon XQL (XML Query Language) of W3C and tightly-coupled with OQL (a query language for object-oriented database). XML document is stored and maintained in BADA-IV, which is an object-oriented database management system developed by ETRI (Electronics and Telecommunications Research Institute) The storage data model is based on DOM (Document Object Model), therefore the retrieval of XML documents is executed basically using DOM tree traversal. We improve the search performance using Node ID which represents node's hierarchy information in an XML document. Assuming that DOW tree is a complete k-ary tree, we show that Node ID technique is superior to DOM tree traversal from the viewpoint of node fetch counts.

• Journal of the Korean Operations Research and Management Science Society
• /
• v.21 no.3
• /
• pp.197-214
• /
• 1996

Financial analysis of stock data usually involves extensive computation of large amount of time series data sets. To handle the large size of the data sets and complexity of the analyses, database management systems have been increasingly adaopted for efficient management of stock data. Specially, relational database management system is employed more widely due to its simplistic data management approach. However, the normalized two-dimensional tables and the structured query language of the relational system turn out to be less effective than expected in accommodating time series stock data as well as the various computational operations. This paper explores a new data management approach to stock data management on the basis of an object-oriented database management system (ODBMS), and proposes a data model supporting times series data storage and incorporating a set of financial analysis functions. In terms of functional stock data analysis, it specially focuses on a primitive set of operations such as variance of stock data. In accomplishing this, we first point out the problems of a relational approach to the management of stock data and show the strength of the ODBMS. We secondly propose an object model delineating the structural relationships among objects used in the stock data management and behavioral operations involved in the financial analysis. A prototype system is developed using a commercial ODBMS.