• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.10a
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• pp.1019-1022
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• 2012

Integral imaging is a promising technology for 3D imaging and display. Many parameters affect the performance of 3D integral imaging systems. Enhanced system performance is acquired by optimization of these system parameters with respect to defined performance metrics. In this paper, we present an approach to optimize the performance of 3D integral imaging system in terms of performance metrics under fixed resource constraints. In this analysis, system parameters such as lens numerical aperture, pitch between image sensors, the number of image sensors, the pixel size, and the number of pixels are determined to optimize performance metrics. Wave optics is utilized to describe the imaging process.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.12 no.6
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• pp.1120-1127
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• 2008

This paper presents implementation of localization system using UWB (Ultra-Wide Band) sensors and its experimental results along with development of context-aware services. In order for precise measurement of position, we experimented various conditions of pitch angles, yaw angles, number of sensors, height of tags along with measuring errors at each installation. As an application examples of the location tracking system, we developed an intelligent health training management system based on context-aware technology. The system provides appropriate training schedule to a trainee by recognizing position of the trainee and current status of gymnastic equipments and note the usage of the equipment through a personal digital assistant (PDA). Error compensation on position data and moving direction of the trainee was necessary for context-aware service. Hence, we proposed an error compensation algorithm using velocity of the trainee. Experimental results showed that proposed algorithm had made error data reduce by 30% comparing with the data without applying the algorithm.

• Transactions on Control, Automation and Systems Engineering
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• v.4 no.3
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• pp.231-238
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• 2002

In this paper, we present a new approach to autopilot design for skid-to-turn missiles which may have severe aerodynamic cross-couplings and nonlinearities with angle of attack. The model of missile motion is derived in the maneuver plane and, based on that model, pitch, yaw, and roll autopilot are designed. They are composed of a nonlinear term which compensates for the aerodynamic couplings and nonlinearities and a linear controller driven by the measured outputs of missile accelerations and angular rates. Besides the outputs, further information such as Mach number, dynamic pressure, total angle of attack, and bank angle is required. With the proposed autopilot and simple estimators of bank angle and total angle of attack, it is shown by computer simulations that the induced moments and some aerodynamic nonlinearities are properly compensated and that the performance is superior to that of the conventional ones.

• Transactions on Electrical and Electronic Materials
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• v.13 no.3
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• pp.129-135
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• 2012

A number of surface mount technology (SMT) process variables including land design are considered for minimizing tombstone defect in flexible printed circuit assembly in high volume manufacturing. As SMT chip components have been reduced over the past years with their weights in milligrams, the torque that once helped self-centering of chips, gears to tombstone defects. In this paper, we have investigated the correlation of the assembly process variables with respect to the tombstone defect by employing statistically designed experiment. After the statistical analysis is performed, we have setup hypotheses for the root causes of tombstone defect and derived main effects and interactions of the process parameters affecting the hypothesis. Based on the designed experiments, statistical analysis was performed to investigate significant process variable for the purpose of process control in flexible printed circuit manufacturing area. Finally, we provide beneficial suggestions for find-pitch PCB design, screen printing process, chip-mounting process, and reflow process to minimize the tombstone defects.

• Journal of the Korea Society of Computer and Information
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• v.10 no.6 s.38
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• pp.47-54
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• 2005

In the most of speaker recognition system, speaker's characteristics is extracted from acoustic parameter by speech analysis and we make speaker's reference pattern. Parameters used in speaker recognition system are desirable expressing speaker's characteristics fully and being a few difference whenever it is spoken. Therefore we su99est following to solve this problem. This paper is proposed to use strong spectrum characteristic in non-noise circumstance and prosodic information in noise circumstance. In a stage of making code book, we make the number of data we need to combine spectrum characteristic and Prosodic information. We decide acceptance or rejection comparing test pattern and each model distance. As a result, we obtained more improved recognition rate than we use spectrum and prosodic information especially we obtained stational recognition rate in noise circumstance.

• Phonetics and Speech Sciences
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• v.3 no.3
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• pp.19-26
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• 2011

Previous laboratory studies have shown that prosodic structures are encoded in the modulations of phonetic patterns of speech including suprasegmental as well as segmental features. Drawing on a prosodically annotated large-scale speech data from the Buckeye corpus of conversational speech of American English, the current study first evaluated the reliability of prosody annotation by a large number of ordinary listeners and later examined whether and how prosodic prominence influences the phonetic realization of multiple acoustic parameters in everyday conversational speech. The results showed that all the measures of acoustic parameters including pitch, loudness, duration, and spectral balance are increased when heard as prominent. These findings suggest that prosodic prominence enhances the phonetic characteristics of the acoustic parameters. The results also showed that the degree of phonetic enhancement vary depending on the types of the acoustic parameters. With respect to the formant structure, the findings from the present study more consistently support Sonority Expansion Hypothesis than Hyperarticulation Hypothesis, showing that the lexically stressed vowels are hyperarticulated only when hyperarticulation does not interfere with sonority expansion. Taken all into account, the present study showed that prosodic prominence modulates the phonetic realization of the acoustic parameters to the direction of the phonetic strengthening in everyday conversational speech and ordinary listeners are attentive to such phonetic variation associated with prosody in speech perception. However, the present study also showed that in everyday conversational speech there is no single dominant acoustic measure signaling prosodic prominence and listeners must attend to such small acoustic variation or integrate acoustic information from multiple acoustic parameters in prosody perception.

• Journal of Broadcast Engineering
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• v.26 no.7
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• pp.838-843
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• 2021

This paper presents an algorithm for effective retrieval of score information to an input score image. The originality of the proposed algorithm is that it is designed to be robust to recognition errors by an OMR (Optical Music Recognition), while existing methods such as pitch histogram requires error induced OMR result be corrected before retrieval process. This approach helps people to retrieve score without training on music score for error correction. OMR takes a score image as input, recognizes musical symbols, and produces structural symbolic notation of the score as output, for example, in MusicXML format. Among the musical symbols on a score, it is observed that filled noteheads are rarely detected with errors with its simple black filled round shape for OMR processing. Barlines that separate measures also strong to OMR errors with its long uniform length vertical line characteristic. The proposed algorithm consists of a descriptor for a score and a similarity measure between a query score and a reference score. The descriptor is based on note-count, the number of filled noteheads in a measure. Each part of a score is represented by a sequence of note-count numbers. The descriptor is an n-gram sequence of the note-count sequence. Simulation results show that the proposed algorithm works successfully to a certain degree in score image-based retrieval for an erroneous OMR output.

• Journal of the Society of Naval Architects of Korea
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• v.60 no.6
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• pp.416-423
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• 2023

Recently, the design point of the propeller is gradually changing due to the demand for energy saving and environmental protection. Until recently, self-propulsion model tests were conducted using stock propellers and geometry information was provided to propeller designers, but the range of existing stock propellers did not keep up with the changing design points, and the range of series propellers required in the initial design was also insufficient. Future propeller performance requires high performance and eco-friendliness, and the need for expansion of series propellers has increased. In order to respond to future needs and provide a wide range of advantages in propeller design, KRISO manufactures about 100 series propellers and builds series data through a model tests. In this paper, the approach method for deriving the representative optimal shape to be applied to the 4-blade series propeller in the initial stage of series propeller development was summarized.

• Journal of the Korea Society of Computer and Information
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• v.15 no.4
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• pp.65-74
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• 2010

At the aim of solving the problems appearing in traditional optical motion capturing systems such as the interference among multiple patches and the complexity of sensor and patch allocations, this paper proposes a new motion capturing system which is composed of a single camera and multiple motion sensors. A motion sensor is consisted of an acceleration sensor and a gyro sensor to detect the motion of a patched body and the orientation (roll, pitch, and yaw) of the motion, respectively. Although Image information provides the positions of the patches in 2D, the orientation information of the patch motions acquired by the motion sensors can generate 3D pose of the patches using simple equations. Since the proposed system uses the minimum number of sensors to detect the relative pose of a patch, it is easy to install on a moving body and can be economically used for various applications. The performance and the advantages of the proposed system have been proved by the experiments.

• Journal of Navigation and Port Research
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• v.28 no.1
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• pp.43-49
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• 2004

Defects inspection of commodities are very important with those design and manufacturing process and essential to strengthen the competitiveness of those. If on-line automatic defects detection is performed without damaging to products, the production cost shall be curtailed through the reducing man-power, economical management of Q.C(Quality Control). In this paper, it is suggested three spatial filtering methods which can extract the necessary information in case of defects being on the surface of object like iron plate. In addition, the dependence of filtering characteristics on parameters such as the pitch and width of slits is analyzed and the surface defect detection system is constructed. Several experiments were carried out for determining the adequate spatial filtering method through comparing and analyzing effects of parameters like defect's size and shape, intensity of light, noise of coherent source and slit number.