• Computers and Concrete
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• v.22 no.6
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• pp.551-561
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• 2018

The percolation of interfacial transition zone (ITZ) in cementitious materials is of great importance to the transport properties and durability issues. This paper presents numerical simulation research on the ITZ percolation threshold of mortar specimens at meso-scale. To simulate the meso-scale model of mortar as realistically as possible, the aggregates are simplified as ellipsoids with arbitrary orientations. Major and minor aspect ratios are defined to represent the global shape characteristics of aggregates. Some algorithms such as the burning algorithm, Dijkstra's algorithm and Connected-Component Labeling (CCL) algorithm are adopted for identification of connected ITZ clusters and percolation detection. The effects of gradation and aspect ratios of aggregates on ITZ percolation threshold are quantitatively studied. The results show that (1) the ITZ percolation threshold is mainly affected by the specific surface area (SSA) of aggregates and shows a global decreasing tendency with an increasing SSA; (2) elongated ellipsoidal particles can effectively bridge isolated ITZ clusters and thus lower the ITZ percolation threshold; (3) as ITZ volume fraction increases, the bridging effect of elongated particles will be less significant, and has only a minor effect on ITZ percolation threshold; (4) it is the ITZ connectivity that is essentially responsible for ITZ percolation threshold, while other factors such as SSA and ITZ volume fraction are only the superficial reasons.

• Journal of the korean academy of Pediatric Dentistry
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• v.49 no.4
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• pp.505-513
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• 2022

Minor orthodontic treatment using a thin wire with high elasticity can shorten the treatment period and reduce the load on the anchorage by the application of light force. Since it can be applied immediately without a dental laboratory procedure and does not require the patient's cooperation, it can be clinically useful. The cases reported here have led to positive results in short periods of treatment, using only a segmented straight 0.012 inch NiTi wire and flowable resin to address various locations within the oral cavity, such as the anterior teeth, premolars, and molars.

• Journal of Biosystems Engineering
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• v.19 no.1
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• pp.9-16
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• 1994

135 and 136 pine cones were sampled from age class of II to VI Korean pine trees for the study of their physical properties in 1991 and 1992, respectively. The length, width, weight, volume, and the largest projected area of cones were measured, and the specific gravity, apparent volume ratio sphericity, and roundness were calculated. Regression analysis were performed for the weight, volume, and projected area to the cone length and width. The length, and major and minor diameters of the cone stalks were measured and analyzed. 1. The range of the length of cone stalks was 0 to 47.3mm. The average length of stalks were 9mm ('91) and 10mm('92), respectively. Cross section of the stalks was ellipse with average major and minor diameters of 9.1mm and 10.1mm, and 8.6 and 8.7mm in 91 and 92, respectively. 2. The length of pine cones distributed from 8cm to 17cm and the average length were about 13cm('91, '92). The width varied from 5cm to 9.5cm and the average width were 6.7cm('91) and 6.9cm('92). The ratios of the length to the width were 0.56('91) and 0.65('91) and the shape of the cones were found to be ellipse with minor diameter of 1/2 to 2/3 of the major diameter. 3. The roundnesses and sphericity of cones were 0.74 and 0.75('91), 0.63 and 0.67('92), respectively. The average of the largest projected area of cones were $85.3cm^2$('91) and $93.1cm^2$('92) and the criterion areas were $71.0cm^2$ and $74.5cm^2$, respectively. 4. Cone weights were from 83g to 467g('91 and '92) and averages were 186g('91) and 220g('92). The average specific gravities were 0.89 and 0.96('91 and '92). The true volumes were $212cm^2$('91) and $230cm^2$('92), and the average bulk volume was $321cm^2$('91, '92). The average apparent volume ratios of cones were 35% ('91) and 28% ('92), respectively. 5. The weight and the volume were proportional to the length of the cone multiplied by the width squred and the largest projected area was proportional to the length multiplied by the width of cones.

• Asian Journal of Atmospheric Environment
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• v.6 no.3
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• pp.234-243
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• 2012

The wintertime high loading for atmospheric pollutants is certainly expected in the Byunsan Peninsula of Korea because of a great-scale reclamation project having construction of 33 km tidal sea dike impounding an area of over 40,000 ha and long-range transport. The goal of this study is to trace the origin of this wintertime burden for ambient particulate matter (hereafter called "PM") in the Byunsan Peninsula of Korea. The size-segregated (i.e., cutoff size from 0.01 ${\mu}m$ to 4.7 ${\mu}m$) PM sampling was conducted at a ground-based site of Byunsan Peninsula located in the west coast of Korean Peninsula during the height of dike constructing. Data archived in this study are the mass concentrations of ionic, elemental, and carbonic components in size-fractioned PM. The elemental mass of individual submicrometer particles was also analyzed. The sum of 5-source (i.e., elemental carbon, organic materials, inorganic secondary pollutants, crustal matter, and sea-salts) concentrations shows the bimodal distribution (major and minor peaks formed around $D_p$, 0.65 ${\mu}m$ and $D_p$, 4.7 ${\mu}m$, respectively) by border with 0.19 ${\mu}m$ of cutoff size. The concentrations of EC in $PM_{1.1-0.01}$ in winter and spring times were 4.62 ${\mu}g\;m^{-3}$ and 3.74 ${\mu}g\;m^{-3}$, respectively. Elemental masses of submicron individual particles are classified into two groups, i.e., the major elements (Cl, Al, Si, S, and P) and the minor trace elements. Cluster analysis differentiated the elements in submicron individual particles into 4-cluster. Among them, three clusters are in agreement with the major (Al, Si, S, and P), minor (Fe, Ca, and K), and trace compositions of coal burning. Meanwhile, Cl classified as an independent cluster has different source profile which was mainly due to the Saemangeum seawall project. Some highly toxic elements (e.g., Cr, Mn, and As (and/or Pb)) were also detected in some part of submicron individual PM. As a consequence, the combination of the Saemangeum project and winter monsoon played a considerable part in the double aggravation of wintertime air pollution in the Byunsan Peninsular.

• Economic and Environmental Geology
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• v.13 no.3
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• pp.141-158
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• 1980

A geologic structure could be formed through various processes, because there are a number of factors which control the deformation of the Earth's crust. In geology, we could call it geological epistemology to describe exactly a geologic structure, and call it geological logics to infer logically the deforming process through which the geologic structure had been formed. Degree of legitimacy of geological logics depends upon the degree of exactness of geological epistemology. This study described quantitatively 3-dimensional Hambaek Syncline through computer analysis, and examined qualitatively into its deforming mechanism based on the results of 3-dimensional analysis of the structure. Input data for the computer analysis are dips and dip directions of bedding planes of the structure. The Hambaek Syncline disclose a minor fold group of NE-SW or NNE-SSW trend and a large scale fold of E-W trend. The conclusions of this study are as follows: (1) The fold of E-W trend is primary fold $(F_1)$ and the minor fold group of NE-SW or NNE-SSW trend secondary fold $(F_2)$. (2) Hambaek Syncline is cylindrical type fold. (3) Apparent axial trace of Hambaek syncline does not coincide with true axial trace. The apparent axial trace is $N70^{\circ}-80^{\circ}W$ in Gohan and Sabuk area, and changes to $N70^{\circ}-80^{\circ}E$ in the westward of the area, while the true axial trace is $N40^{\circ}-70^{\circ}W$ in the former, and $N60^{\circ}-80^{\circ}E$ in the latter area. (4) Westward dipping of axial plane of the minor fold group of NE-SW or NNE-SSW trend can be attributed to simple shear movements along overthrusts. (5) Angle between axial trace and the directional trace of the maximum principal compressive stress $({\sigma}_1)$ may not be perpendicular each other. The angle between them is governed by the following factors; 1) the plunge of fold axis 2) the dip of axial surface 3) cylindrisity (6) The mean axial trace of Hambaek Syncline $(F_1)$ is $N45.6^{\circ}W$, and the directional trace of ${\sigma}_1$ is $N52.4^{\circ}E$ (7) The mean axial trace of the minor fold group of NE-SW or NNE-SSW trend $(F_2)$ is $N21^{\circ}E$, and the directional trace of ${\sigma}_1$ is $N22^{\circ}W$.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.11
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• pp.80-85
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• 2016

Pat Metheny debuted in 1976 and attracted the public beyond his genre in jazz by committing experimental and various music. His 50 albums have been recognized with musicality and artistry by winning 20 Grammy Awards and being awarded a Gold Disc 3 times. Therefore, his music cannot be expressed merely with the single word 'jazz'. In basic harmonics, there are distinct chords between major chord and minor chord. For example, Ionian Scale and Lydian Scale are used in major chord and Dorian Scale, Phrygian Scale, and Aeolian Scale are used in minor chord. It is also common to use m7b5 chord in Locrian Scale. However, after analyzing Pat Metheny's scale, he made Lick using Dorian Scale in major chord or using Lydian Scale in minor chord. In Dominant chord that can use various six scales, he often used Dorian Scale or Lydian Scale surprisingly. In some measures, he made Lick using Ionian Scale and Lydian Scale. In this case, since the whole atmosphere of that measure simultaneously expresses both the bright feeling of major and the lonely feeling of minor, it arouses a very special atmosphere. In addition, he brought 12-measure pattern and made Lick not using blues scale but often using Ionian Scale, Lydian Scale, and Mixo-Lydian Scale.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.10a
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• pp.80-80
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• 2018

Hosta is a genus of the family Asparagaceae and distributed in East Asia. There are six Hosta species (Hosta capitata (Koidz.) Nakai, H. clausa Nakai, H. jonesii M.G.Chung, H. minor (Baker) Nakai, H. venusta F.Maek., and H. yingeri S.B.Jones) native to Korea and among them, four species (H. minor, H. jonesii, H. venusta and H. yingeri) are endemic to the Korea peninsula. Hosta is generally propagated by seed, crown division or tissue culture. However, tissue culture is a more efficient method to mass proliferation, a new cultivar development and disease-free plantlet production in a limit time. Hence, we conducted this study to evaluate the influence of various plant growth regulators (PGRs) treatments on the induction of callus and somatic embryo of the six Hosta species. Leaf, petiole and root were used to select optimum tissue culture explants. Petiole explants thus only were used for callus induction and somatic embryogenesis with TDZ (0.1, 0.5 or 1.0mg/L) and NAA (0.1 or 0.5 mg/L) combinations. After 12 weeks of culture, the highest rate of somatic embryogenesis was achieved on modificated MS medium containing 1.0 mg/L TDZ and 0.1 mg/L NAA in H. capitata and H. minor (15.5%, respectively), 0.1 or 0.5 mg/L TDZ and 0.1 mg/L NAA in H. jonesii (22.2%), 1.0 mg/L TDZ and 0.5 mg/L NAA in H. yingeri (26.7%), and 0.1 mg/L TDZ and 0.5 mg/L NAA in H. venusta (53.3%). H. clausa showed very low effect on somatic embryogenesis by PGRs; 2.2%. There was interspecies difference to PGRs respond for callus and somatic embryo induction. Regenerated multiple shoots and plantlet of H. minor, H. jonesii, H. venusta and H. yingeri were obtained via somatic embryogenesis.

• Physical Therapy Korea
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• v.24 no.2
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• pp.48-57
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• 2017

Background: Rounded shoulder posture (RSP), a postural abnormality, might cause shoulder pain and pathologic conditions. Although most previous research has investigated RSP focusing on the proximal structures of the shoulder, such as the scapula and pectoralis muscles, the relationship between RSP and anterior distal structures of the upper extremity, such as the biceps brachii muscle and elbow joint, is not clearly understood. Objects: This study aimed to investigate the correlations between RSP and the biceps brachii length, elbow joint angle (EJA), pectoralis minor length, general pectoralis major length, humeral head anterior translation (HHAT), glenohumeral internal rotation (IR), external rotation (ER), and horizontal adduction (HAD). Methods: Twelve subjects with RSP (6 male, 6 female) were recruited. All subjects fulfilled the RSP criteria indicated by a distance ${\geq}2.5cm$ from the posterior aspect of the acromion to the table in the supine position. The examiner measured each of the following parameters twice: RSP, biceps brachii length, EJA, pectoralis minor length, pectoralis major length, HHAT, glenohumeral IR, ER, and HAD. Pearson's correlation coefficient(r) was used to assess the correlation between RSP and all the variables. Results: There was a significant moderate positive correlation between RSP and biceps brachii length (r=.55, p=.032), moderate negative correlation between RSP and pectoralis minor length (r=-.62, p=.015), and moderate positive correlation between RSP and HHAT (r=.53, p=.038). Conclusion: The biceps brachii length, pectoralis minor length, and HHAT could be used to evaluate patients with RSP. Better understanding of the correlation between these factors and RSP could help in the development of effective methods to treat patients with this condition in clinical management.

• Journal of the korean academy of Pediatric Dentistry
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• v.29 no.3
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• pp.413-417
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• 2002

Mucocele is a mucous retention phenomenon which is caused by a laceration to the duct of minor salivary glands causing extravasation of mucin into the connective tissue forming a cyst-like space. Sialolithiasis of minor salivary glands and chronic obstruction of salivary glands may also cause such a phenomenon. Mucocele is a smooth, rounded sessile mass with diameters varying from 1 to 15mm of sudden appearance. Mucocele tying directly beneath the mucosa may rupture spontaneously and decrease in size, but frequently recurs. Lower lip is most frequently affected, and the mouth floor and buccal vestibule may also be affected. Enucleation of the cyst is needed and removal of minor salivary glands, marsupialization and cryotherapy may also be done. The mucocele frequently recurs after its removal. A 1-year-old female patient visited the hospital with a complaint of a swelling on the lower lip since 4 months before. She had no pain history but 4 months ago, fell and such symptom appeared since then. On her first visit, a bullous solid, opaque lesion of 5mm in diameter was noted. Treatment choice of surgical approach and nonsurgical approach were explained to the guardian. Considering the patient's age, the guardian agreed to a nonsurgical procedure. Treatment was carried out by tieing 3-0 silk to the base of the lesion. One week later, the tie loosened and was re-tied. A week later, the mucocele disappeared. Mucocele on the lower lip may be usually be treated by surgical removal, but this may traumatize the surrounding minor salivary gland causing it to recur. Also, surgicial removal may induce an ischemic change causing sialometaplasia. In case of young patients or children with management problems, non-surgical methods such as this tie method may be used. This tie method does not need any local anesthesia and has no pain, no secondary infection, and low bleeding tendency.

• The Korean Journal of Food And Nutrition
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• v.21 no.3
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• pp.355-365
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• 2008

The purpose of this study was to investigate the food sanitation awareness and performance of foodservice industry employees. Based on a literature review, a questionnaire was developed to identify the food sanitation education, experience, knowledge, and food sanitation practices of the employees. A total of 376 Korean food industry employees participated, and there were 344 usable questionnaires. In the analysis of food sanitation knowledge, the statements "clip fingernails short and do not use nail polish", and "if feeling sick, even with a minor cold, speak to your supervisor immediately", had the highest and lowest percentages of correct answers, respectively. In assessing employee sanitary management practices, many correctly acknowledged "clip fingernails short and do not use nail polish" and "wash hands after using the toilet", which received high scores; however, "use hands to pick up ice" and "if feeling sick, even with a minor cold, speak to your supervisor immediately" had low scores. The sanitary knowledge and practice levels of the employees were not significantly different according to gender, age, work area, job title, or duration of duty. Among the surveyed industries, employees of special restaurants had the least sanitary knowledge(p<0.05) and practice scores(p<0.001). Employees who had worked for $1{\sim}3$ years presented the least sanitary management practice level scores(p<0.05).). In addition, college students and participants without hygiene educational experience showed the least levels of sanitary knowledge(p<0.01). Scores for sanitary management practice were higher when hygiene education was regularly conducted more than once per month. Employees showed significantly higher knowledge and sanitary management practice levels when they were required to use a sanitary checklist(p<0.001), and employees who were trained in HACCP had significantly higher sanitary checklist scores(p<0.05). In foodservices that applied HACCP, the employees showed higher knowledge and sanitary management practice levels(p<0.001).