• Journal of the Society of Naval Architects of Korea
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• v.28 no.2
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• pp.52-68
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• 1991

A new propeller series is developed using the newly developed blade section(KH18 section) which behaves better cavitation characteristics and higher lift-drag ratio at wide range of angle-of-attack. The pitch and camber distributions are disigned in order to have the same radial and chordwise loading distribution with the selected circumferentially averaged wake input. Since the geometries of the series propeller, such as chord length, thickness, skew and rate distribations, are selected by regression of the recent full scale propeller geometric data, the performance prediction of a propeller at preliminary design stage can be mure realistic. Number of blades of the series propellers is 4 and the expanded blade area ratios are 0.3, 0.45, 0.6 and 0.75. Mean pitch ratios are selected as 0.5, 0.65, 0.8, 0.75 and 1.1 for each expanded area ratio. The new propeller series is composed of 20 propellers and is named as KD(KRISO-DAEWOO) propeller series. Propeller open water tests are performed at the experimental towing tank, and the cavitation observation tests and fluctuating pressure measurements are carried out at the cavitation tunnel of KRISO. $B_{P}-\delta$ curves, which can be used to select the optimum propeller diameter at the preliminary design stage, are derived from a regression analysis of the propeller often water test results. The KD-cavitation chart is derived from the cavitation observation test results by choosing the local maximum lift coefficient and the local cavitation number as parameters. The caviy extent of a propeller can be predicted more accurately by using the KD-cavitation chart at a preliminary design stage, since it is derived from the results of the cavitation observation tests in the selected ship's wake, whereas the existing cavitation charts, such as the Burrill's cavitation chart, are derived from the test results in uniform flow.

• The korean journal of orthodontics
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• v.34 no.5 s.106
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• pp.417-428
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• 2004

The purpose of this study was to evaluate the stress distributions at the periodontal ligament (PDL) and displacements of the maxillary first molar when mesially directed force was applied under various molar angulations and rotations. A three dimensional finite element model of the maxiilary first molar and its periodontal ligament was made Upright position, mesially angulated position by $20^{\circ}$ and distally angulated position of the same degree were simulated to investigate the effect of molar angulation. An anteriorly directed force of 200g countertipping moment of 1,800gm-mm (9:1 moment/force ratio) and counterrotation moment of 1,000gm-mm (5:1 moment/force ratio) were applied in each situation. To evaluate the effect of molar rotation on the stress distribution, mesial-in rotation by $20^{\circ}$ and the same amount of distal-in rotation were simulated. The same force and moments were applied in each situation. The results were as follows: In all situations, there was no significant difference in mesially directed tooth displacement Also, any differences in stress distributions could not be found, in other words. there were no different mesial movements. Stress distributions and tooth displacement of the $20^{\circ}$ mesially angulated situation were very similar with those of the $20^{\circ}$ distal-in rotated situation. The same phenomenon was obserned between the $20^{\circ}$ distally angulated situation and $20^{\circ}$ mesial-in rotated situation. When the tooth was mesially angulated, or distal-in rotated, mesially directed force made the tooth rotate in the coronal plane. with its roots moving buccally, and its crown moving lingually. When the tooth was distally angulated, or mesial-in rotated, mesially directed force made the tooth rotate in the coronal plane, with its roots moving lingually and its crown moving buccally. When force is applied to au angulated or rotated molar, the orthodontist should understand that additional torque control is needed to prevent unwanted tooth rotation in the coronal plane.

• The Journal of the Petrological Society of Korea
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• v.17 no.4
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• pp.191-205
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• 2008

In order to use the geologic information data such as industrialization of rock resources, site enlargement and development planning, distributive ratios of rock types and geologic ages were obtained by the ArcGIS 9.2 program, and digital geologic and geographic maps of 1:250,000 scale, in the Chungbug, Chungnam and Daejeon areas, respectively. In the Chungbug area, 64 rock kinds are developed and their geologic ages can be classified into 8 large groups. In the geologic ages, the ratios are decreasing in the order of Jurassic, Precambrian, Age-unknown, Cretaceous, Quaternary, Cambro-Ordovician and Carboniferous-Triassic ages, all of which comprise most ratios of 98.48% in the area. In the rock types, the ratios show the decreasing order of Jurassic Daebo granite, Precambrian banded gneiss of Gyeonggi metamorphic complex, Cretaceous biotite granite, Quaternary alluvium, Great limestone group, Lower phyllite zone and Meta-sandy rock zone of age-unknown Ogcheon group, Triassic Cheongsan granite, Precambrian granitic gneiss of Gyeonggi gneiss complex, Pebble bearing phyllite zone of age-unknown Ogcheon group and biotite gneiss of Sobaegsan metamorphic complex, all of which comprise the prevailing ratio of 84.27% in the area. In the Chungnam area, 35 rock types are developed and their geologic ages can be classified into 6 large groups. In the geologic ages, the ratios are decreasing in the order of Precambrian, Jurassic and Quaternary ages, which occupy the prevailing ratio of 87.55% in the area. In the rock types, the ratios show the decreasing order of Jurassic Daebo granite, Precambrian banded gneiss of Gyeonggi metamorphic complex, Quaternary alluvium, Precambrian granite and granitic gneiss of Gyeonggi gneiss complex, Cretaceous acidic dykes, Lower phyllite zone and Pebble bearing phyllite zone of age-unknown Ogcheon group and Quaternary reclaimed land, which occupy the ratios of 74.28% in the area. In the Daejeon area, 11 rock types are developed and their geologic ages can be classified into 5 large groups. In the ages, the ratios are decreasing in the order of Jurassic, Age-unknown and Quaternary, which occupy most ratios of 93.40% in the area. In the rock types, the ratios show the decreasing order of Jurassic Daebo granite, Quaternary alluvium and Lower phyllite zone and Pebble bearing phyllite zone of age-unknown Ogcheon group, which occupy the prevailing ratios of 91.09% in the area.

• The Korean Journal of Mycology
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• v.38 no.1
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• pp.75-79
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• 2010

A total of 25 isolates of Fusarium fujikuroi were obtained from diseased rice plants in Korea from 2006 to 2007 to assess their resistance against fungicides prochloraz and benomyl + thiram. Minimal inhibitory concentration (MIC) values of F. fujikuroi isolates were examined by agar dilution method. Most of the isolates were sensitive to the fungicides. Out of 25 isolates, six were resistant to prochloraz and three to benomyl + thiram. In addition, the isolates CF245, CF249 and CF337 showed resistant to both fungicides. The progenies ($F_1$ isolates) obtained through two different crosses between sensitive parental isolates(CF202, CF232 and CF179) and resistant parental isolate (CF337) were evaluated for their mycelial growth at different temperatures and resistance against fungicides. Mycelial growth rate of $F_1$ isolates originated from CF202 $\times$ CF232 was similar to the parental isolates. However mycelial growth rate of $F_1$ isolates originated from CF179 $\times$ CF337 was faster than their parent isolates. In case of prochloraz, distribution ratio of sensitivity(S) to resistance(R) against to the fungicide of $F_1$ isolates originated from CF202 $\times$ CF232 and CF179 $\times$ CF337 was 86 : 14 and 78 : 22, respectively. In case of benomyl+thiram, all the $F_1$ isolates originated from CF202 $\times$ CF232 were sensitive to the fungicide, however ratio of sensitivity(S) to resistance(R) against to the fungicide of $F_1$ isolates originated from CF179 $\times$ CF337 was 35 : 65.

• Radiation Oncology Journal
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• v.13 no.3
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• pp.277-283
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• 1995

Purpose : This study was performed to measure dose alteration at the air-tissue interface resulting from rebuild-up to the loss of charged particle equilibrium in the tissues around the air-tissue interfaces. Materials and Methods : The 6 and 10-MV photon beam in dual energy linear accelerator were used to measure the surface dose at the air-tissue interface The polystyrene phantom sized $25{\times}25{\times}5\;cm^3$ and a water phantom sized $29{\times}29{\times}48\;cm^3$ which incorporates a parallel-plate ionization chamber in the distal side of air gap were used in this study. The treatment field sizes were $5{\times}5\;cm^2,\;10{\times}10\;cm^2\;and\;20{\times}20\;cm^2$. Air cavity thickness was variable from 10 mm to 50 mm. The observed-expected ratio (OER) was defined as the ratio of dose measured at the distal junction that is air-tissue interface to the dose measured at the same point in a homogeneous phantom. Results : In this experiment, the result of OER was close or slightly over than 1.0 for the large field size but much less (about 0.565) than 1.0 for the small field size in both photon energy. The factors to affect the dose distribution at the air-tissue interface were the field size, the thickness of air cavity. and the photon energy. Conclusion : Thus, the radiation oncologist should take into account dose reduction at the air-tissue interface when planning the head and neck cancer especially pharynx and laryngeal lesions, because the dose can be less nearly $29{\%}$ than predicted value.

• Journal of Korean Society of Forest Science
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• v.79 no.4
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• pp.367-375
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• 1990

In order to determine the effects of bedrock, organic matter, calcium and iron oxide on the soil aggregation, this research has performed with soils from bedrock regions of Limestone, Granite and Granite gneiss. This research was also to estimate how organic matter, calcium and iron oxide influence on soil aggregation under different forest conditions in various bedrock regions. And it also had a purpose to rate physical factors relevant to soil aggregation, their characteristics and aggregate diameter which closely relates to stabilities in the process of soil erosion. The following conclusions have been drawn in response to the overall research objectives. The rates of the soil aggregation on different bedrock regions were 21% in Limestone bedrock, 19.8% in Granite bedrock and 9.9% in Granite gneiss bedrock. A main factor in soil aggregation was the orgainc matter content in soils and the rate of soil aggregation increased in the constant proportion with the organic matter content. The relation could be formulated into Y=4.31X-4.37(Y : aggregation ratio X : organic matter content). The soil aggregation ratio under the deciduous forests eras higher than that under the coniferous forests. It was considered that this resulted from differences in organic matter content. Soil aggregates with larger diameter than 0.5mm were found more in Limestone bedrock than other smaller size soil aggregates of 0.25mm diameter were more distributed in Granite gneiss bedrock. Granite bedrock region had normal distribution in soil aggregate sizes with the highest frequency of 0.5mm diameter. Calcium and iron oxides had only partial influences on the soil aggregation in some specific conditions. But in Limestone bedrock region calcium influenced on the soil aggregation with the organic matter content.

• Journal of Oral Medicine and Pain
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• v.34 no.2
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• pp.207-216
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• 2009

Trigeminal neuralgia is defined "a sudden, usually unilateral, severe, brief, stabbing, recurrent pain in the distribution of one or more branches of the fifth cranial nerve". The initial treatment of choice for trigeminal neuralgia is medical therapy. In patients with medically intractable pain or intolerable medication side effects, invasive therapeutic approaches are often necessary. Based on the amount of evidence and estimated efficacy, carbamazepine is the drug of choice in the management of trigeminal neuralgia. In case of insufficient or no response to carbamazepine, second-line drugs can be added. In this study, the author tried to review and analyzed the cases of 90 patients whom had visited for treatment of trigeminal neuralgia at the Department of Oral Medicine, Kyungpook National University Hospital from 2003 to 2008. The results were as follows: 1. Trigeminal neuralgia was significantly more common with advancing age, and nearly twice as common in women than men (ratio of 2.1:1) 2. The maxillary branch of the trigeminal nerve involved most often (51.1%), and the right side of the face is affected more commonly than the left (ratio of 2.9:1). 3. 85(94.4%) patients had experiences visiting medical or dental specialties before being referred to the Department of Oral Medicine. 4. 40(44.4%) patients with trigeminal neuralgia had systemic diseases. 5. Treatment with carbamazepine monotherapy was satisfactory initially in 69(76.7%) the patients, and the mean daily dose of carbamazepine was 402.9mg. On the other hand, 16(17.8%) patients expressed effectiveness after combination therapy of carbamazepine and other drugs. 6. Of the 69 patients who had a good initial response to carbamazepine monotherapy, 18 patients became resistant, so that combination therapy of carbamazepine and other drugs were necessary. 7. 54(60%) patients developed side effects such as dizziness, drowsiness, nausea, vomiting, blood dyscrasias, skin rash and constipation, and 11 of the patients decided to stop tmedicaion due to side effects.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1976.06a
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• pp.87.4-88
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• 1976

The statistcal study was done on 81 cases of the foreign bodies in the food passages (73 cases) and air passages (8 cases), who had visited the Dept. of Otolaryngology of Kyung Hee Medical Center and treated endoscopically, from Nov. 1971 to Mar 1976. The results were as follows, 1) The incidence of esophageal foreign bodies (73 cases) in order of frequency was coin (61 cases; 83.6%), bone (6 cases; 8.2%), food particles (3 cases; 4.1%), discs (2 cases), and other metals (l case). The incidence of foreign bodies in the air passages (8 cases) was food particles (3 cases; 37.5%), pointed metal (2 cases; 25%), plastic pencil cap (l case), plastic ring (1 case), and wood piece (1 case) in order. 2) In sex distribution, 51 cases (62.9%) were males and 30 cases (37.1%) were females, and the ratio between males and females was about 1.7 : 1.3. In the age incidence, 69 cases (82.5%) of all foreign bodies were under 5 years of age, and especially, coin cases were 59 cases (96.7%) and the highest was 8 years of age, lowest was 11 months of age. 7 cases (87.5%) of all airway foreign bodies were under 10 years of age. 4) The ratio between the food passages(73 cases) and the air passages (8 cases) was about 9 : 1. In the location of the foreign bodies of the food passages, 66 cases (90.4%) were in the first esophageal narrowing, 5 cases (6.9%) in the second narrowing, and 2 cases (2.7%) in the third narrowing. In the air passages, the frequent sites were trachea (5 cases; 62.5%), larynx (2 cases), and bronchus (1 case) in order. 5) In duration of lodgement, 63 cases (86. 3%) of esophageal foreign bodies were removed within 24 hours, and one case was removed within 16 days. The number of cases lodged within 24 hours were 4 cases (50%). in the air passages and one case was removed within 18 days. 6) In treatment, 37 cases (50.7%) of esophageal foreign bodies were extracted by modified upper esophagoscopy, 33 cases (42.5%) by esophagoscopy under the local anesthesia, 3 cases (4.1%) by esophagoscopy under the general anesthesia. 8 cases of the coin cases were passed into the stomach during the endoscopic examination. Laryngeal foreign bodies (2 cases; 25%) were extracted by laryngoscopy under the local anesthesia. 2 cases (40%) of tracheal foreign bodies by Bronchoscopy with tracheotomy under the local anesthesia, 3 cases (60%) by Bronchoscopy under the general anesthesia, and bronchial foreign body (1 case) by open thoracotomy under the general anesthesia, at the Dept. of Chest surgery.

• Food Engineering Progress
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• v.14 no.2
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• pp.85-91
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• 2010

In the food process, twist screen is widely used to divide particles on the basis of size. As screen equipped in the twist screen perfoms an important part in the particle size distribution mechanism, the contact area of screen and particles, retention time of particles on the screen, mesh and string thickness of screen and the flow pattern of particles on the screen are major points of the separation efficiency. To improve the separation efficiency, increase the retention time and control the flow pattern of particles, screen frame dam and spiral blockage are installed on the sieve of twist screen ${\emptyset}$ 1200 and ${\emptyset}$ 1500. Twist screen ${\emptyset}$ 1500 with frame dam treated similar separation capacity, 37% higher separation ratio and less non-separated particles of product output 1 than general twist screen. Twist screens with frame dam and spiral blockage showed less treatment capacity, three times higher division ratio and entire separation than general twist screen.

• Korean Journal of Heritage: History & Science
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• v.50 no.4
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• pp.122-147
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• 2017

The Jungsandong sites are distributed across quartz and mica schist formations in Precambrian, and weathering layers include large amounts of non-plastic minerals such as mica, quartz, felspar, amphibole, chlorite and so on, which form the ground of the site. Neolithic pottery from Jungsandong exhibits various brown colors, and black core is developed along the inner part for some samples, and sharp comb-pattern and hand pressure marks can be observed. Their non-plastic particles have various composition, size distribution, sorting and roundness, so they are classified into four types by their characteristic mineral compositions. I-type (feldspar pottery) is including feldspar as the pain component or mica and quartz. II-type (mica pottery) is the combination of chloritized mica, talc, tremolite and diopside. III-type (talc pottery) is with a very small amount of quartz and mica. IV-type (asbestos pottery) is containing tremolite and a very small amount of talc. The inner and outer colors of Jungsandong pottery are somewhat heterogeneous. I-type pottery group shows differences in red and yellow degree, depending on the content of feldspar, and is similar to III-type pottery. II-type is similar to IV-type, because its red degree is somewhat high. The soil of the site is higher in red and yellow degree than pottery from it. The magnetic susceptibility has very wide range of 0.088 to 7.360(${\times}10^{-3}$ SI unit), but is differentiated according to minerals, main components in each type. The ranges of bulk density and absorption ratio of pottery seem to be 1.6 to 1.7 and 13.1 to 26.0%, respectively. Each type of pottery shows distinct section difference, as porosity and absorption ratio increase in the order as follows: I-type (organic matter fixed sample) < III-type and IV-type < I-type < II-type (including IV-type of IJP-15). The reason is that differences in physical property occur according to kind and size of non-plastic particles. Although Jungsandong pottery consists of mixtures of various materials, the site pottery has a geological condition on which all mineral composition of Jungsandong pottery can be provided. There, it is thought that raw materials can be supplied from weathered zone of quartz and mica schist, around the site. However, different constituent minerals, size and rock fragments are shown, suggesting the possibility that there can be more raw material pits. Thus, it is estimated that there may be difference in clay and weathering degree.