• Journal of Korean Vacuum Science & Technology
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• v.6 no.1
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• pp.5-7
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• 2002

For quantitative N depth profiling, N profiles were measured in a～3 m Si oxynitride by low energy O$\sub$2+/sputtering and the result was calibrated with MEIS analysis of the N thickness and areal density. The quantitative depth profile of nitrogen showed the pileup of nitrogen atoms at the interface of ultrathin oxynitride films.

• Natural Product Sciences
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• v.17 no.3
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• pp.225-229
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• 2011

A new approach for similarity analysis of chemical profiles of Scrophularia buergeriana was developed. The roots of S. buergeriana collected in Andong, Korea were analyzed using HPLC-DAD and the peak areas of the chromatograms were used to construct the chemical profiles of S. buergeriana. The analytical conditions were validated for specificity, precision and repeatability. The standard chemical profiles were established from the chromatograms of nine standard analytical extracts from three batches. The correlation coefficients of peak areas of characteristic compounds between the chromatograms of the standard and test samples were calculated for quantitative expression of the chemical profiles. The results showed that the HPLC chemical profiles of the samples of same geographic origin were relatively consistent. This new approach could be applied to the quality assessment of herbal medicines with complex chemical compositions.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.5
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• pp.2101-2121
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• 2020

The rapid growth of instructional videos repositories and their widespread use as a tool to support education have raised the need of studies to assess the quality of those educational resources and their impact on the quality of learning process that depends on them. Khan Academy (KA) repository is one of the prominent educational videos' repositories. It is famous and widely used by different types of learners, students and teachers. To better understand its characteristics and the impact of such repositories on education, we gathered a huge amount of KA data using its API and different web scraping techniques, then we analyzed them. This paper reports the first quantitative and descriptive analysis of Khan Academy repository (KA repository) of open video lessons. First, we described the structure of repository. Then, we demonstrated some analyses highlighting content-based growth and evolution. Those descriptive analyses spotted the main important findings in KA repository. Finally, we focused on users' interactions with video lessons. Those interactions consisted of questions and answers posted on videos. We developed interaction profiles for those videos based on the number of users' interactions. We conducted regression analysis and statistical tests to mine the relation between those profiles and some quality related proposed metrics. The results of analysis showed that all interaction profiles are highly affected by video length and reuse rate in different subjects. We believe that our study demonstrated in this paper provides valuable information in understanding the logic and the learning mechanism inside learning repositories, which can have major impacts on the education field in general, and particularly on the informal learning process and the instructional design process. This study can be considered as one of the first quantitative studies to shed the light on Khan Academy as an open educational resources (OER) repository. The results presented in this paper are crucial in understanding KA videos repository, its characteristics and its impact on education.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.1313-1315
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• 2003

This paper is dedicated to studying the quantitative analysis method with remote-sensing data in shallow geological structure reconstruction by the example of TM data in western China. A new method of computing attitude of geological contacts from remote-sensing data is developed and assessed. We generate several geological profiles with remotely derived measurements to constrain the shallow geological structure reconstruction in three dimensions.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.1205-1210
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• 2005

The behavior of rock mass and solute(e.g. groundwater, radioactivity) flow in fractured rock can be directly influenced by joint roughness. The characteristics of joint roughness is also a main factor for the rock classification(e.g. RMR, Q system) which is usually used in tunnel design. Nevertheless, most of JRC estimation has been carried out only by the examination with the naked eye. This JRC estimation has a lack of objectivity because each investigator judges JRC by his subjective opinion. Therefore, it will be desirable that the assessment of JRC is performed by a numerical analysis which can give a quantitative value corresponding to the characteristics of a roughness curve. Meanwhile, roughness curves for joint surfaces which are observed in drill cores have been obtained only along linear profiles. Although roughness curves are measured in the same joint surface, they can frequently show diverse aspects in a standpoint of roughness characteristics. If roughness curves can be measured along the elliptical circumferences of joint surfaces from core scanning images or Televiewer images, they will certainly be more comprehensive than those measured along linear profiles for roughness characteristics of joint surfaces. This study is focus on dealing with (1) extracting automatically roughness curves from core scan image or Televiewer image, (2) improving the accuracy of quantitative assessment of JRC using fractal dimension concept.

• Journal of Biomedical Engineering Research
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• v.12 no.1
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• pp.43-48
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• 1991

As the computerized methods and equipments In nuclear medicine imaging increases, quantitative information is needed on the single photon emission computed tomographic Images as well as on the conventional nuclear medicine images. In this paper, the authors investigated the effect of several clinician - friendly reconstrution filters on the resultant transverse slices of backprojected Profiles of radioisotope distribution from the Quantitative point of view, and reduced the filter parameters such as cutoff frequency and order of filter which are neces mary to minimize the quantification error using computer-generated phantoms.

• Journal of Biomedical Engineering Research
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• v.3 no.1
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• pp.51-54
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• 1982

As the computerized methods and equipments in nuclear medicine imaging increases, quantitative information is needed on the single photon emission computed tomographic images as well as on the conventional nuclear medicine images. In this paper, the authors investigated the effect of several clinician - friendly reconstrution filters on the resultant transverse slices of backprojected profiles of radioisotope distribution from the quantitative point of view, and reduced the filter Parameters such as cutoff frequency and order of filter which are necessary to minimize the quantification error using computer -generated phantoms.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.6A
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• pp.765-778
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• 2008

Performance Profiles are essential to predict the performance variation over time for the bridge management system (BMS) based on risk management. In general, condition profiles based on experts opinion and/or visual inspection records have been used widely because obtaining profiles based on real performance is not easy. However, those condition profiles usually don't give a good consistency to the safety of bridges, causing practical problems for the effective bridge management. The accuracy of performance evaluation is directly related to the accuracy of BMS. The reliability of the evaluation is important to produce the optimal solution for distributing maintenance budget reasonably. However, conventional methods of bridge assessment are not suitable for a more sophisticated decision making procedure. In this study, a method to compute quantitative performance profiles has been proposed to overcome the limitations of those conventional models. In Bridge Management Systems, the main role of performance profiles is to compute and predict the performance of bridges subject to lifetime activities with uncertainty. Therefore, the computation time for obtaining an optimal maintenance scenario is closely related to the efficiency of the performance profile. In this study, the Response Surface Method (RSM) based on independent and important design variables is developed for the rapid computation. Steel box bridges have been investigated because the number of independent design variables can be reduced significantly due to the high dependency between design variables.

• Journal of Oral Medicine and Pain
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• v.44 no.3
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• pp.103-111
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• 2019

Purpose: Patients with taste complaints presenting with various abnormal perceptions and alterations in gustatory function are often encountered in dental clinics. Since taste perception is thought to be influenced by numerous factors including neurological and psychological factors, the gustatory profiles of patients complaining of taste abnormalities should be very different. However, the gustatory profiles based on the clinical subtypes of taste complaints have not been fully studied. This study aimed to better understand the gustatory profiles depending on the clinical subtypes of taste complaints. Methods: Clinical data from 169 patients with complaints of altered taste were retrospectively collected to analyse their clinical and gustatory profiles. These complaints were subdivided into hypergeusia, hypogeusia, and dysgeusia for each taste quality according to the clinical types of these complaints. The gustatory profiles were then established by analysing the detection and recognition thresholds for each taste quality depending on the clinical subtypes of taste complaints. Results: Clinical analysis revealed that patients with taste complaints had widely diverse clinical profiles. There were significant differences between males and females with taste complaints in the prevalence rates of symptoms like dry mouth, tongue coating, and burning sensation. While hypogeusia (76.3%) was the most frequent type of taste complaint, it was revealed that the taste thresholds were not always consistent with the patient's description of gustatory symptoms. Conclusions: Patients with taste complaints exhibited diverse clinical profiles with sex differences. Considering the diversity of the taste complaints, the quantitative gustatory testing methods can be valuable to differentially evaluate the presence and intensity of altered taste in patients with these complaints.

• Korean Journal of Mineralogy and Petrology
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• v.35 no.4
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• pp.431-445
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• 2022

A quantitative phase analysis method of X-ray powder diffraction was studied to determine the mineral content of clay-rich rocks practically as well as effectively. For quantitative X-ray powder diffraction analysis of the clay-rich rocks, it is necessary to prepare whole-rock powder samples with a random orientation by side mounting method. In addition, for the identification of the clay minerals in the rock, it is required to prepare an oriented mount specimen with a clay particle size of 2 ㎛ or less, ethylene glycol treatment, and heat treatment. RIR (reference intensity ratio) and Rietveld method were used for the quantitative analysis of the clay-rich rocks. It was possible to obtain the total clay and the non-clay minerals contents from the whole-rock X-ray diffraction profiles using the RIR values. In addition, it was possible to calculate the relative content of each clay mineral from the oriented X-ray diffraction profiles of the clay particle size and assign it to the total clay. In the Rietveld method of whole-rock X-ray diffraction, effective quantitative values were obtained from the Rietveld diffraction patterns excluded the region of less than 10 degrees (2θ). Similar quantitative values were shown in not only the RIR but the Rietveld methods. Therefore, the analysis results indicate a possibility of a routine quantitative analysis of clay-rich rocks in the laboratory. However, quantitative analysis of clay minerals is still a challenge because there are numerous varieties of clay minerals with different chemical and structural characteristics.