• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.7
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• pp.387-392
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• 2019

A technique was researched to detect bolt looseness using a transfer impedance technique (the dual piezoelectric material technique) for monitoring the structural health of a bolt joint. In order to use the single piezoelectric material technique, an expensive impedance analyzer should be used. However, in the transfer impedance technique, low-cost fault detection can be performed using a general function generator and a digital multimeter. A steel plate frame test specimen composed of bolt joints was fabricated, and the tightening torques of the bolts were loosened step by step. By using the transfer impedance method, the damage index was obtained. It was found that the presence of faults could be reasonably estimated using the damage index, which increased with the degree of bolt looseness. An experiment was performed on the same specimen using the single piezoelectric material technique, and the results showed a similar tendency. It could be possible to estimate the damage of a bolt joint at low cost by eliminating the expensive impedance analyzer. This method could be used effectively for structural health monitoring after carrying out a study to estimate the fault location and severity.

• Current Optics and Photonics
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• v.4 no.1
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• pp.44-49
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• 2020

In this paper, a new method is presented to measure the refractive index of single plain glass or multilayered materials, based on a laser frequency-shifted confocal feedback microscope. Combining the laser frequency-shifted feedback technique and the confocal effect, the method can attain high axial-positioning accuracy, stability and sensitivity. Measurements of different samples are given, including N-BK7 glass, Silica plain glass, and a microfluidic chip with four layers. The results for N-BK7 glass and Silica plain glass show that the measurement uncertainty in the refractive index is better than 0.001. Meanwhile, the feasibility of this method for multilayered materials is tested. Compared to conventional methods, this system is more compact and has less difficulty in sample processing, and thus is promising for applications in the area of refractive-index measurement.

• Journal of Korean Library and Information Science Society
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• v.35 no.3
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• pp.271-291
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• 2004

Such information services source like digital library has been asked information services of atypical multimedia database like image, voice, VOD/AOD. Examined in this study are suggestions such as word-phrase generator, syllable recoverer, morphological analyzer, corrector for voice processing. Suggested voice processing technique transform voice database into tort database, then extract index database from text database. On top of this, the study suggest a information retrieval model to use in extracted index database, voice full-text information retrieval.

• Journal of the Optical Society of Korea
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• v.9 no.2
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• pp.49-53
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• 2005

We report a new configuration of a reflection-type confocal scanning optical microscope system for measuring the refractive index profile of an optical waveguide. Several improvements on the earlier design are proposed; a light emitting diode (LED) at 650 nm wavelength instead of a laser diode (LD) or He-Ne laser is used as a light source for better index precision, and a simple longitudinal linear scanning and curve fitting techniques are adapted instead of a servo control for maintaining an optical confocal arrangement. We have obtained spatial resolution of 700 nm and an index precision of $2\times10^{-4}$. To verify the system's capability, the refractive index profiles of a conventional multimode fiber and a home-made four-mode fiber were examined with our proposed measurement method.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.25 no.2
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• pp.1-10
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• 2002

Process capability indices are widely used in industries and quality assurance system. In past years, process capability analysis have been used to characterize process performance on the basis of univariate quality characteristics. However, in actual manufacturing industrial, statistical process control (SPC) often entails characterizing or assessing processes or products based on more than one engineering specification or quality characteristic. Therefore, the analysis have to be required a multivariate statistical technique. This paper introduces to multivariate capability indices and then selects a multivariate process capability index incorporated both the process variation and the process deviation from target among these indices under the multivariate normal distribution. We propose a new multivariate capability index $MC_{pm}^+$ using quality loss function instead of the process variation and this index is compared with the proposed indices when quality characteristics are independent and dependent of each other.

• Journal of Korea Spatial Information System Society
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• v.9 no.2
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• pp.13-23
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• 2007

Recently there is growing Interest in LBS(Location Based Service) requiring real-time services and the spatial main memory DBMS for efficient Telematics services. In order to optimize existing disk-based multi-dimensional Indexes of the spatial main memory DBMS in the main memory, multi-dimensional index structures have been proposed, which minimize failures in cache access by reducing the entry size. However, because the reduction of entry size requires compression based on the MBR of the parent node or the removal of redundant MBR, the cost of MBR reconstruction increases in index update and the efficiency of search is lowered in index search. Thus, to reduce the cost of MBR reconstruction, this paper proposed the RSMBR(Relative-Sized MBR) compression technique, which applies the base point of compression differently in case of broad distribution and narrow distribution. In case of broad distribution, compression is made based on the left-bottom point of the extended MBR of the parent node, and in case of narrow distribution, the whole MBR is divided into cells of the same size and compression is made based on the left-bottom point of each cell. In addition, MBR was compressed using a relative coordinate and size to reduce the cost of search in index search. Lastly, we evaluated the performance of the proposed RSMBR compression technique using real data, and proved its superiority.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.5
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• pp.971-977
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• 2021

The purpose of this research paper is: (1) to describe the service quality index; (2) describe the data quality index; and (3) describe the anti-corruption index of BPS Trenggalek, Indonesia. The approach chosen is quantitative with the type of survey research. The primary data collection technique was mainly based on a questionnaire distributed to 40 respondents, namely BPS service users in 5 (five) categories: the private sector, the banking industry, academics, offices, or agencies in Trenggalek Regency and universities. The results showed that the quality of BPS services was good and the data quality index where the respondents were satisfied with the data presented by BPS. Meanwhile, testing the anti-corruption index shows that BPS Trenggalek is very anti-corruption in providing services to consumers. The findings of this study suggested that to improve service quality, it is necessary to pay attention to several aspects, including published service requirements, easy requirements to be fulfilled, published procedure information, clear service process flow, published service times, and costs/tariffs are communicated. This study suggests updating data, data relevance, data accessibility, and data completeness to improve data quality. Furthermore, to maintain the very anti-corruption predicate, this study suggests maintaining service by upholding the prevailing ethics and norms.

• Journal of Korean Society of Forest Science
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• v.101 no.3
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• pp.395-404
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• 2012

This study was conducted to develop site index equations and to estimate productive areas for major coniferous species in Korea such as Pinus densiflora Sieb. et. Zucc, Pinus densiflora for. erect, Larix leptolepis and Pinus koraiensis using environmental factors. Using the large data set from both a digital forest site map and a climatic map, a total of 43 environmental factors including 15 climatic variables were regressed on site index by tree species to develop site index equations. Six environmental factors by species were selected as independent variables in the final site index equations. The result showed that the coefficients of determination for site index equations by species were ranged from 0.36 to 0.56, which seem to be relatively low but good enough for the estimation of forest stand productivity. The site index equations developed in this study were also verified by three evaluation statistics such as the estimation bias of model, precision of model, and mean square error of measurement. According to the evaluation statistics, it was found that the site index equations by species fitted well to the test data sets with relatively low bias and variation. As a result, it was concluded that the site index equations by species were well capable of estimating site quality. Based on the site index equations, the productive areas by species for all forest areas were estimated by applying GIS technique to the digital forest site map and climate map. In addition, the distribution of productive areas by species was illustrated by using GIS technique.

• Journal of the korean academy of Pediatric Dentistry
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• v.33 no.4
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• pp.686-692
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• 2006

The impacted teeth were surgically exposed by the closed-eruption technique and orthodontically retracted. The subject of this study are 24 patients(Mx. insiors; 10 Mx. canines; 14) who finished their treatment. The periodontal condition of the impacted teeth and the normally erupted proximal and opposed teeth were compared and analysed. The results are the followings ; 1. When the gingival index, plaque index, pocket depth and attached gingiva in periodontal evaluation were compared, there was no significant difference between the study group and the control group (P>0.05). 2. When the alveolar bone support of the mesial and the distal surface of the maxillary central incisors and proximal teeth was compared, there was no significant difference between the study group and the control group (P<0.05). 3. When the alveolar bone support of the maxillary canines was compared, there was no significant difference between the retracted teeth and the normally erupted teeth(P>0.05). The results above showed that the surgical exposure by closed-eruption technique followed by the orthodontic retraction of the impacted teeth has a positive influence on the regeneration of gingival tissue in clinical practice and is esthetically more stable. And it is considered that the clinicians should give attention to the direction of retraction power and the maintenance of normal shape of the alveolar bone in treatment of maxillary central incisors.

• Archives of Craniofacial Surgery
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• v.19 no.1
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• pp.3-12
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• 2018

Background: Millard's rotation-advancement repair, which is used by many surgeons, can make a natural philtral column, but most surgeons use a modification of the rotation-advancement flap. The purpose of this article is to introduce a modification utilized by the authors and to provide detailed surgical procedure. Methods: We retrospectively reviewed 82 patients' medical records and presented surgical technique and outcomes. The main features of the authors' strategy are emphasizing horizontal length of the lip, orbicularis oris muscle duplication for improving the definition of the philtral column, overcorrection of domal portion than the non-cleft side in order to compensate for the recurrence during growth. Two judges rated two times the appearance of the patients' nose and lip using Asher-McDade aesthetic index. Intra- and interobserver reliabilities were determined using Cohen's kappa statistics. Results: All patients recovered eventually after surgery; however, two patients have a minor complications (wound infection in one patient, wound disruption due to trauma in the other patient). The improvement of the aesthetic results can be achieved with this modified Millard technique. Total mean scores of the Asher-McDade index was 2.08, fair to good appearance. The intraobserver reliabilities were substantial to almost perfect agreement and the interobserver reliabilities were moderate to almost perfect agreement. Conclusion: We modified Millard method for repair of complete unilateral cleft lip. The surgical outcomes were favorable in long-term follow-up. We hope our technique will serve as a guide for those new to the procedure.