• Journal of the korean academy of Pediatric Dentistry
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• v.38 no.2
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• pp.109-118
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• 2011

The aims of this study were analyze the amount of stress condition when the traction force was applied to the condyle head from the chin area of mandible and amount of distortion condition when intended 0.5 mm distraction distance from surface or one point of dissected midline of mandible. For this study, 3D finite element analysis were performed. The following results were obtained : 1. When traction force of 500 g was applied to the condyle head from the chin area, condylar neck area showed the greatest amount of stress and coronoid process was the least amount of stress area. For the amount of distortion condition, infra dental area showed the greatest. 2. When 0.5 mm of intended surface distortion was applied after dissection of mid-mandible area, base anterior area showed the greatest amount of stress but the least stress area was coronoid process. For the amount of distortion, infra dental, menton area showed the greatest amount. 3. One point distortion was applied after dissection of mid-mandible area, ramus posterior area showed the greatest amount of stress and menton area were the least stress condition. For the amount of distortion, menton area showed the greatest amount of distortion condition.

• Journal of Dental Rehabilitation and Applied Science
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• v.36 no.1
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• pp.1-11
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• 2020

Purpose: The purpose was to compare shear bond strength (SBS) of three types of resin for temporary restoration to polyetherketoneketone (PEKK) depending on surface modification. Materials and Methods: Sixty disks made from PEKK were air-abraded with 110 ㎛ alumina particles (Cobra, Renfert GmbH, Hilzinge, Germany) and thirty specimens were divided into two groups each: PEKK without Visio.link (Bredent, Senden, Germany)(U) and with Visio.link (P). Resins for temporary restoration (polymethylmethacrylate; PMMA, polyethylmethacrylate; PEMA, bis-acryl composite resin) in the shape of a square with one side 3.2 mm were bonded to PEKK twenty respectively and classified into six groups (UM, UE, UC, PM, PE and PC). All specimens were stored in distilled water at 37℃ for 24 hours. SBS of each group was measured at a crosshead speed of 2 mm/min in universal testing machine. SBS was compared using one-way ANOVA and a Tukey HSD test (P = 0.05). Results: Group UM and group UE showed a significant difference in SBS with group UC (P < 0.05). Group PC showed a significant increase in SBS than group UC (P < 0.05). Conclusion: It is recommended to apply Visio.link to PEKK for adhering bis-acrylic composite resin, but not for PMMA and PEMA in clinical practice.

• Culinary science and hospitality research
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• v.15 no.2
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• pp.173-187
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• 2009

The purpose of this study is to provide useful information for establishing efficient marketing direction by investigating the performance(satisfaction) and importance of the display of dining space for hotel banquets. The importance and satisfaction scores of the display of dining space were measured on the five-point Likert scale. The results were summarized as follows. 'Taste of food(4.53 point)', 'freshness of food materials(4.50 point)', and 'indoor cleanliness(4.38 point)' were considered highly important while 'carpet shape of the floor(3.68 point)' and 'art objects(3.69 point)' were scored low. As for the factors of satisfaction, 'freshness of food materials(3.86 point)', 'taste of food(3.85 point)', 'indoor cleanliness(3.74 point)', and 'overall cleanliness of tables(3.73 point)' were considered highly satisfactory while 'art objects(3.42 point)', 'item decoration(3.44 point)', 'furniture and accessory decoration(3.45 point)' were scored low. As a result of analyzing difference between importance and performance of the display of dining space, importance(4.02 point) was much higher than performance(3.60 point). For the IPA result, customers made much account of 'taste of food', 'freshness of food materials', 'indoor cleanliness', 'overall cleanliness of tables', 'cleanliness state of a banquet hall' and so on, so they were regarded as the items to be continuously cared for. Also, intensive care was needed in such factors as 'indoor temperature', 'food vessels', 'soundproofing' and 'colors of a banquet hall' due to low customer satisfaction.

• Applied Microscopy
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• v.39 no.2
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• pp.149-156
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• 2009

Fine structure of the dry adhesion system in the tarsal appendages of the jumping spider Plexippus setipes (Araneae: Salticidae) with examined using field emission scanning electron microscope (FESEM). The jumping spiders have the distinctive attachment apparatus for adhesion on smooth dry surface without sticky fluids. They attach to rough substrates using tarsal claws, however attachment on smooth surfaces is achieved by means of a tuft-like hair called a scopula. All eight legs have the scopulae with a pair of claws on the tip of feet, and each scopula is composed of two groups of setae that are capable of dry adhesion on smooth surface. The apex of each seta is flattened pad bearing many specialized adhesive setules on one side. The cuticular sensillae are interspersed at the dorsal surface of the seta. It has been revealed by this research that the contact area of the setule is always a triangular shape, and these cuticular surfaces are connected by the elongated stalks from the underlying setae. Moreover, adhesion between the numerous setules and the setae was prevented by the microscopic hairs, since these were interspersed on the upper side of the setae.

• Applied Microscopy
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• v.39 no.2
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• pp.141-147
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• 2009

The antennae of millipedes have a prominent function in detecting various types of environmental stimuli, and structural modification of the antennae is closely associated with the degree of sense recognition. Although the biological significance of the antennal sensillae to millipedes are widely understood, the structure and function of the antennal sensillae are still not clear and more precise analysis is required. We have analysed the ultrastructural characteristics of the antennal sensillae in a millipede Anaulaciulus koreanus koreanus using field emission scanning electron microscopy (FESEM). According to their morphological and substructural features, we could identify three different types of antennal sensillae as follows: trichoid sensilla (TS), chaetiform sensilla (CS) and basiconic sensilla (BS). The TS on the articles are long, blunt-tipped, almost straight hairs with deep longitudinal grooves in their lower parts whereas, the CS are long, sickleshaped bristles with longitudinal grooves acuminating toward the tip. The BS can be subdivided further into three subtypes which are the large-sized basiconic sensilla ($BS_1$), the small-sized basiconic sensillae ($BS_2$) and the spiniform basiconic sensillae ($BS_3$). The BS between the terminal segment and distal margins of the other segments are clearly discriminated in this species.

• Research in Plant Disease
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• v.22 no.2
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• pp.122-126
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• 2016

In June 2015, an exhibited typical signs and symptoms of brown rot was observed on fruit of Apricot cvs. Modern and Alexander at an incidence of 5% of fruit in Jeonju, Korea. Early symptoms on fruit showed small, circular, light brown spots that eventually destroyed the entire fruit. Small sporodochia appeared on the fruit surface. Fruit susceptibility to brown rot increases during the 1 to 2 weeks period prior to harvest. The conidia were one-celled, hyaline, lemon-shaped, $14.6-18.0{\times}8.5-11{\mu}m$, and borne in branched monilioid chains. Based on the morphological characteristics and phylogenetic analysis of internal transcribed spacer (ITS), the fungus was identified as Monilinia fructicola. A BLAST search revealed that sequences of the fungus shared 100% identity to those of M. fructicola. Pathogenicity of a representative isolate was proved by artificial inoculation, fulfilling Koch's postulates. To our knowledge, this is the first confirmed report on the occurrence of M. fructicola on apricot in Korea.

• Research in Plant Disease
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• v.23 no.4
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• pp.322-333
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• 2017

In June and July 2015 and 2017, typical signs and symptoms of brown rot were observed on the fruit of Japanese apricot, peach, apricot, Japanese plum, and sweet cherry with incidence levels of 2-5% in Jeonju and Imsil, Korea. Early symptoms were small, circular, light brown spots that eventually destroyed entire fruit. Small sporodochia later appeared on the surface. Conidia isolated from each host were one-celled, hyaline, lemon-shaped and borne in branched monilioid chains. The optimal temperature range for hyphal growth of all the isolates was $20-25^{\circ}C$. The growth of hyphae was faster on potato dextrose agar and oatmeal agar than others. Multiple alignments using the ITS sequences from different host showed that they matched each other (100%). The ITS sequences showed 100% identity to those of M. fructicola. Based on the morphological characteristics and phylogenetic analysis via internal transcribed spacer (ITS), all the isolate was identified as M. fructicola. Pathogenicity of representative isolates was proved by artificial inoculation, fulfilling Koch's postulates. This is the first confirmed report on brown rot caused by M. fructicola on stone fruit in Korea.

• Korean Journal of Materials Research
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• v.10 no.3
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• pp.204-211
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• 2000

The $(Y,Gd)BO_3:Eu$ red phosphors for PDP application were synthesized by ultrasonic spray method and then their photoluminance properties were investigated under 147nm VUV irradiation. The precursor solution of acetates of Y, GD and Eu and boric acid diluted in water was sprayed using 1.7 MHz ultra-sonic sprayer into the reaction tube held at high temperature. The as-sprayed particles were amorphous phase having C-C and C-H bonds due to the insufficient thermal reaction during the pass along the tube. But the sprayed samples followed by heat treatment at $1100^{\circ}C$ had the same crystal structure and chemical composition as those samples followed by solid state reaction. It was found that the $(Y_{0.7}Gd_{0.3})_{0.95} BO_3:Eu_{0.05}^{3+}$ phosphor particles synthesized by spray at $500^{\circ}C$ and then heat treated at $900^{\circ}C$ had a spherical-like shape and fine particle size at $0.7{\mu\textrm{m}}$ having a narrow size distribution, while the phosphor particles made by solid state reaction was $3{\mu\textrm{m}}$ coarse and non-uniform size distribution. The emitting intensity under 147nm VUV excitation for $(Y_{0.7}Gd_{0.3})_{0.95}BO_3:Eu_{0.05}^{3+}$ phosphor prepared by spray method was found to be higher than those phosphor made by solid state reaction and the commercial $(Y,Gd)BO_3:Eu$ product.

• Journal of Conservation Science
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• v.26 no.3
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• pp.277-294
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• 2010

The Seosanmaaesamjonbulsang (National Treasure No. 84) consists of light gray and coarse to mediumgrained biotite granite with partly developed pegmatite and quartz vein. The host rock is divided into dozens of rock blocks with various shape along irregular discontinuity plane. The evaluation results of discontinuity systems reveal that the host rock were exposed to instable sloping environments. Results of deterioration diagnosis show that the degree of damage has been made worse by physical weathering and surface discoloration laying stress on part that vertical and horizontal joints are massed. Generally, deterioration rate of the triad Buddha surface cover with 42.7%, however, the rate of physical weathering and surface discoloration are subdivided to 9.6% and 33.1%, respectively. Ultrasonic measurements indicate that the triad Buddha was reached highly weathered grade in general. And the rock material was weaken to show low velocity zone of 1,000m/s along irregular joint systems. Indoor and outdoor mean relative humidity of the shelter was recorded more than 70% during every season, and high frequency appears in high relative humidity range over 95%. Such environments seem to have produced dew condensation on the rock surface with rainfall and supply water, promoted physical, chemical and biological weathering along crack and joint, resulting in high permeation of water and percentage of water content. Therefore, it is judged that for scientific conservation of the triad Buddha it needs environment control through persistent preservation environment monitoring including water problem.

• Food Science and Preservation
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• v.15 no.6
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• pp.810-815
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• 2008

Improving quality is a very important component of maintaining competitiveness of agricultural products. However, evaluation of 'high quality' indicates it is a very abstract concept and independent of some quality attributes, leading to differences in the perception of quality. Thus, there is a pressing need to objectively define 'high quality' and to develop basic technologies for its measurement, for application in the production, storage and distribution of competitive agricultural products. To objectively quantify apple quality, a survey was conducted on consumer preferences and awareness of quality attributes including color, taste, flavor and shape. The survey questionnaire targeted male and female adults (463 persons) ranging in age from 20 to 59 years. The questionnaire was based on purchases made at a wholesale market (50.1%) or a traditional market (18.8%). The majority of purchases were as small packets (62.0%) or as individual pieces (20.5%). Apples of moderate size (fist size, 60.5%) were preferred over small (4.3%) or large (32.6%) apples. The questionnaire provided consumer data on external quality attributes including color, shape and variety. Taste attributes were evaluated in relation to the balance between sour and sweet taste, and flavors peculiar to apples.