• Journal of Technologic Dentistry
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• v.46 no.3
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• pp.93-100
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• 2024

Purpose: This study aimed to generate virtual mandibular first molars using deep learning technology, specifically deep convolutional generative adversarial network (DCGAN), and evaluate the accuracy and reliability of these virtual teeth by analyzing their morphological characteristics. These morphological characteristics were classified based on various evaluation criteria, facilitating the assessment of deep learning-based dental prosthesis production's practical applicability. Methods: Based on our previous research, 1,000 virtual mandibular first molars were generated, and based on morphological criteria, categorized as matching, non-matching, and partially matching. The generated first molars or the categorization of the generated molars were analyzed through the expert judgment of dental technicians. Results: Among the 1,000 generated virtual teeth, 143 (14.3%) met all five evaluation criteria, whereas 76 (7.6%) were judged as completely non-matching. The most frequent issue, with 781 (78.1%) instances, including some overlapping instances, was related to occlusal buccal cusp discrepancies. Conclusion: The study reveals the potential of DCGAN-generated virtual teeth as substitutes for real teeth; however, additional research and improvements in data quality are necessary to enhance accuracy. Continued data collection and refinement of generation methods can maximize the practicality and utility of deep learning-based dental prosthesis production.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.5C
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• pp.487-495
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• 2007

When error occurs during the network transmission of the image, the quality of the restored image is very serious. Therefore to maintain the received image quality, the error concealment technique is necessary. This paper presents an efficient spatial error concealment method using adaptive edge-oriented interpolation. It deals with errors on slice level. The proposed method uses boundary matching method having 2-step processes. We divide error block into external and internal region, adaptively restore each region. Because this method use overall as well as local edge characteristics, it preserves edge continuity and texture feature. The proposed technique reduces the complexity and provide better reconstruction quality for damaged images than the previous methods.

• Journal of Digital Convergence
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• v.11 no.12
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• pp.353-359
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• 2013

The search method that web services offers has its limitations. The search service considers only functional factors based on the client's preferences. In order to improve the web service search - which alone only considers functional factors - our research introduces an execution phase which performs both functional and non-functional factors by utilizing WSDL and matching information. Our research studies the architecture of both the service selecting method and the selecting process to help determine the best service solution for the client. We do so, taking into consideration the client's preferences. Our research also studies selecting methods for the best overall service. This service not only considers the matching of functional factors provided by the web service's selecting process, but it is also accommodating by matching the information as defined by the client. This paper research can offer the best quality service preferred by any end-user. Again, this is done by utilizing web services that considers the user's non-functional factors identified by the web service's selecting process and also by extracting matching information.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.27 no.12
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• pp.1112-1115
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• 2016

Global Positioning System(GPS) is a useful system used in both civilian and military applications. However, the signal of GPS is susceptible to jamming attacks due to low receive sensitivity, since the signals come from the satellite located at over 20,000 km above the earth. In this paper, we have conducted a preceding research on a non-Foster matching circuit that efficiently matches an electrically ultra-small GPS antenna. Electrically Small Antennas(ESAs) are inefficient radiators and are difficult to match in wideband due to extremely high quality factor. In order to match small GPS antenna in wideband, a non-Foster matching circuit for a small GPS antenna was designed. A negative impedance converter circuit consisting of Linvill's cross-coupled pair transistors was fabricated and its stability was verified by the time-domain stability analysis. In addition, anechoic chamber measurements show that the non-Foster matching circuit for small GPS antenna can lead bore-sight gain improvement by more than 17 dB.

• The KIPS Transactions:PartB
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• v.9B no.5
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• pp.653-662
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• 2002

Fingerprint recognition is a task to find a matching pattern in a database for a specific persons fingerprint. To accomplish this task, preprocessing, classification, and matching steps are taken for a large-scale fingerprint database but only the matching step is taken without classification for a small-scale database. The primary matching method is based on minutiae (ridge ending point, bifurcation). This matching method, however, requires a very complex computation to extract minutiae and match minutiae-to-minutiae accurately due to translation, rotation, nonlinear deformation of fingerprint and occurrence of spurious minutiae. In addition, this method requires a laborious preprocessing step in order to improve the quality of fingerprint Images. This paper proposes a new simple method to eliminate these problems. With this method, Gabor variance is used instead of minutiae for fingerprint recognition. The Gabor variance is computed from Gabor features that result from filtering a fingerprint image through Gabor filter. In this paper, this method is described and its test result is shown, demonstrating the potential of using this new method for fingerprint recognition.

• Journal of Korean Traditional Oncology
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• v.27 no.1
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• pp.25-36
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• 2022

The Randomized Control Trial (RCT) is the most well-established and widely used statistical methodology in clinical research; however, applying thorough RCT to cancer patients presents challenges such as ethical concerns, high costs, short clinical periods, and limitations in collecting various side effects. To address this issue, the propensity score matching method, which takes advantage of the benefits of observational research while compensating for the drawbacks of randomized control trials, is used in a variety of fields. In recent years, 28 studies on the effectiveness of Korean medicine on tumors have been conducted abroad using the Propensity Score Matching Method, but none have been conducted in Korea. The majority of studies have focused on liver cancer, colon cancer, lung cancer, and stomach cancer, with endpoints such as survival time, incidence rate, quality of life, and treatment outcomes revealing statistical differences in how Korean medicine intervention affects treatment outcomes. As a result, well-established studies using the propensity matching score methodology should be useful in evaluating the impact of Korean medicine in oncology treatments.

• Quality Improvement in Health Care
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• v.12 no.1
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• pp.104-112
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• 2006

Background : The necessity of unify and standardize codes used at hospital has been emphasized since OCS (Order Communicating System) was adopted. Therefore, the purpose of this study were to standardize operation code by continuous training of the ICD-9-CM code that is used as standard code in OCS program at operating room. Method : In 400 operation data, operation code entered in OCS program at operating room was compared to operation name recorded in medical record. In addition, a matching rate between input data of operation code by medical record department and computing input data of operation code in 3,710 cases was compared for each department. User operation name and operation code were matched and major diagnosis by operation department and operation name were also matched. Results : User operation name was reflected in operation classification code in detail, and operation code entered on user was registered. Input rate and matching rate of operation code were gradually improved after improvement activity. In particular, a matching rate was high at ophthalmology where operation name is segmented. Plastic surgery and orthopedics with a lot of emergency operation and comprehensive operation name show low input rates. Conclusions : As the medical field makes progress in computerlization, awareness of information exchange and sharing becomes higher. Among codes to classified medical institution, codes related to surgical operation are all different by user of hospital and department. Computerlization and standardization is essential. And when efforts of standardization continue in alliance with individual hospital and institution, initiative of preparing medical policy data at a national level will be accelerated.

• The Journal of the Acoustical Society of Korea
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• v.20 no.2
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• pp.77-85
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• 2001

This paper proposes a method of time-scale modification of polyphonic audio signals based on a sinusoidal model. The signals are modeled with sinusoidal component and noise component. A multiresolution filter bank is designed which splits the input signal into six octave-spaced subbands without aliasing and sinusoidal modeling is applied to each subband signal. To alleviate smearing of transients in time-scale modification a dynamic segmentation method is applied to subbands which determines the analysis-synthesis frame size adaptively to fit time-frequency characteristics of the subband signal. For extracting sinusoidal components and calculating their parameters matching pursuit algorithm is applied to each analysis frame of subband signal. In accordance with spectrum analysis a psychoacoustic model implementing the effect of frequency masking is incorporated with matching pursuit to provide a resonable stop condition of iteration and reduce the number of sinusoids. The noise component obtained by subtracting the synthesized signal with sinusoidal components from the original signal is modeled by line-segment model of short time spectrum envelope. For various polyphonic audio signals the result of simulation shows suggested sinusoidal modeling can synthesize original signal without loss of perceptual quality and do more robust and high quality time-scale modification for large scale factor because of representing transients without any perceptual loss.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.43 no.1 s.307
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• pp.75-84
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• 2006

With considering center-biased characteristic, NTSS(New Three-Step Search Algorithm) can improve the performance of TSS(Three-Step Search Algorithm) which is one of the most popular fast block matching algorithms(BMA) to search a motion vector in a video sequence. Although NTSS has generally better Quality than TSS for a small motion sequence, it is hard to say that NTSS can provide better quality than TSS for a large motion sequence. It even deteriorates the quality to increase a search window size using NTSS. In order to address this drawback, this paper aims to develop a new adaptive window size-based three step search scheme, called AWTSS, which can improve quality at various window sizes in both the small and the large motion video sequences. In this scheme, the search window size is dynamically changed to improve coding efficiency according to the characteristic of motion vectors. AWTSS can improve the video quality more than 0.5dB in case of large motion with keeping the same quality in case of small motion.

• Journal of Korean Society for Geospatial Information Science
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• v.23 no.1
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• pp.129-135
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• 2015

The Ubiquitous City (U-City) spatial information technology aimed to provide services freely anytime and anywhere by converging high-tech information & communication technology in urban infrastructure has been available in diverse patterns. In particular, there have been studies on the development of 3D spatial information after selecting and matching key points with stereo images from the many Closed Circuit TV (CCTV) in the U-City. However, the data mostly used in extracting matching points haven't considered external environmental impacts such as illuminance. This study tested how much the matching points needed to construct 3D spatial information with the CCTV whose image quality is dependent upon changes in illuminance fluctuate under the same hardware performances. According to analysis on the number of matching points by illuminance, the number of matching points increased up to 3,000Lux in proportion to the illuminance when IRIS, shutter speed and ISO were fixed. In addition, a border between an object and background became more distinctive. When there was too much light, however, the page became brighter, and noise occurred. Furthermore, it was difficult to name key points because of the collapse of an inter-object border. It appears that if filmed with the study results, the number of matching points would increase.