• The Korean Journal of Malacology
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• v.28 no.1
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• pp.7-12
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• 2012

The effect of water temperature on spawning induction, larval development, spat settling and its growth of the cockle shell, Fulvia mutica, were investigated to obtain the basic data for effective seed production. The eggs, which were randomly divided into 6 groups of water temperatures of 14, 17, 20, 23, 26 and $29^{\circ}C$, were transferred into 1 L beaker, respectively. The relationships between the water temperature and the required time (1/h, hour) by each egg developmental stage were calculated. Biological minimum water temperature and the cumulative water temperature until egg development of the veliger stage were calculated to be $0.1^{\circ}C$ and $397.3^{\circ}C$, respectively. The optimal water temperature for developmental bioassay of F. mutica was clarified to be $23^{\circ}C$. The required time for the embryo to become veliger larvae was 20 hours at $23^{\circ}C$.

• Journal of the Korean Vacuum Society
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• v.18 no.1
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• pp.54-59
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• 2009

We have measured the spatiotemporal behavior for the density of excited Xe atoms in the $1s_5$ metastable states by laser absorption spectroscopy in accordance with various shapes of ITO electrode. The maximum density of excited Xe atoms in the Is5 state in a discharge cell for fish-boned, T-shaped and squared ITO electrodes has been measured to be $3.01{\times}10^{13}\;cm^{-3}$, $2.66{\times}10^{13}\;cm^{-3}$ and $2.06{\times}10^{13}\;cm^{-3}$, respectively. Throughout this experiment, we could understand the influence of the shapes of ITO electrode of micro discharge cell on the high efficiency of AC-PDPs.

• Korean Journal of Plant Resources
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• v.21 no.5
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• pp.374-387
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• 2008

This study was carried out to investigate the distribution of the useful resources plants and the flora of the sand dune on South Coast and Jeju Island. The flora of sand dune on South Coast and Jeju Island was investigated from February to November in 2006. Vascular plants of this area consist of total 171 taxa; 1 forma, 18 varieties, 152 species, 130 genera, 51 families. The dominant species in the vegetations of the south coast sand dune were Calystegia soldanella, Ischaemum anthephoroides, Vitex rotundifolia, Carex pumila, Carex kobomugi. It corresponds to 11.1 % of totally 4,071 taxa appeared in Korea. Useful plants of this area were investigated 113 taxa. It corresponds to 66% of collected plants in this area under our study. Among the useful plants, there are 73 taxa of edible source, 61 taxa of medicinal source, 22 taxa of pasture source, 16 taxa of ornamental source, 7 taxa of fiber source, 1 taxa of timber source. Korean endemic plants were composed 1 taxa.

• Korean Journal of Plant Taxonomy
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• v.39 no.4
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• pp.277-291
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• 2009

The flora in the region of Songnisan National Park ($N36^{\circ}28^{\prime}05^{{\prime}{\prime}}{\sim}36^{\circ}46^{\prime}38^{{\prime}{\prime}}$, $E\;127^{\circ}47^{\prime}06^{{\prime}{\prime}}{\sim}127^{\circ}57^{\prime}50^{{\prime}{\prime}}$) was surveyed from April 2000 to July 2006. Vascular plants in 26 collections included a total of 723 taxa: 115 families, 392 genera, 629 species, 4 subspecies, 72 varieties and 18 forms. Ninety-three of these taxa were first records for the region. In the flora of Songnisan National Park, 27 taxa were Korean endemic plants, 19 taxa were rare and endangered plants as designated by the Korea Forest Service. Forty-five of the taxa were with the levels III, IV, V in the floristic regional indicator plants which was designated by Korean Ministry of Environment, and 29 taxa were alien plants now naturalized in Korea. Owing to their unusual phytogeography and low number of populations, the taxa Crypsinus hastatus (Thunb.) Copel., Paeonia japonica (Makino) Miyabe & Takeda, Jeffersonia dubia (Maxim.) Benth. & Hook.f. ex Baker & S.Moore, Bupleurum euphorbioides Nakai, Phacellanthus tubiflorus Siebold & Zucc., Lilium cernuum Kom., Gastrodia elata Blume and Cephalanthera erecta var. subaphylla (Miyabe & Kud ) Ohwi were considered the most important. Based on these results, it is clear that appropriate plans to conserve the natural habitat of Songnisan National Park must be made immediately.

• Tuberculosis and Respiratory Diseases
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• v.83 no.4
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• pp.289-294
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• 2020

Background: Line probe assay (LPA) is standard diagnostic tool to detect multidrug resistant tuberculosis. Non-interpretable (NI) results in LPA (complete missing or light wild-type 3 and 8 bands with no mutation band in rpoB gene region) poses a diagnostic challenge. Methods: Sputum samples obtained between October 2016 and July 2017 at the Intermediate Reference Laboratory, All India Institute of Medical Sciences Hospital, New Delhi, India were screened. Smear-positive and smear-negative culture-positive specimens were subjected to LPA Genotype MTBDRplus Ver 2.0. Smear-negative with culture-negative and culture contamination were excluded. LPA NI samples were subjected to phenotypic drug susceptibility testing (pDST) using MGIT-960 and sequencing. Results: A total of 1,614 sputum specimens were screened and 1,340 were included for the study (smear-positive [n=1,188] and smear-negative culture-positive [n=152]). LPA demonstrated 1,306 (97.5%) valid results with TUB (Mycobacterium tuberculosis) band, 24 (1.8%) NI, three (0.2%) valid results without TUB band, and seven (0.5%) invalid results. Among the NI results, 22 isolates (91.7%) were found to be rifampicin (RIF) resistant and two (8.3%) were RIF sensitive in the pDST. Sequencing revealed that rpoB mutations were noted in all 22 cases with RIF resistance, whereas the remaining two cases had wild-type strains. Of the 22 cases with rpoB mutations, the most frequent mutation was S531W (n=10, 45.5%), followed by S531F (n=6, 27.2%), L530P (n=2, 9.1%), A532V (n=2, 9.1%), and L533P (n=2, 9.1%). Conclusion: The present study showed that the results of the Genotype MTBDRplus assay were NI in a small proportion of isolates. pDST and rpoB sequencing were useful in elucidating the cause and clinical meaning of the NI results.

• Journal of Korean Philosophical Society
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• v.117
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• pp.373-397
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• 2011

Nicht nur in Philosophie sondern auch im Bereich der meinsten Geisteswissenschaften $best{\ddot{a}}rkt$ sich die Gewichtigkeit des Spielbegriffs immer mehr. Aus diesem Grund wird 'Spiel' in den $vielf{\ddot{a}}ltigen$ Wissenschaftsbereichen, in $vielf{\ddot{a}}ltiger$ Weise definiert, und diese Definitionen sind im Gebrauch auch in $vielf{\ddot{a}}ltiger$ Weise. Aber trotz dieser mit Spiel $zusammenh{\ddot{a}}ngenden$ '$Vielf{\ddot{a}}ltigkeiten$' liegt immer eine identische Voraussetzung am Boden der Definitionen oder Theorien des Spiels, und das ist nichts anderes als, dass Spiel ausnahmslos eine Vertieftsein-$T{\ddot{a}}tigkeit$ ist. Anders gesagt, dass es kein Spiel gibt, in dem man sich nicht $v{\ddot{o}}llig$ aufgeht. Aber diese Ansicht ist vorwiegend nur im Abendland in Geltung, und deswegen ist es sehr bedenklich, ob man das auch auf dem Morgenland gleichfalls zutreffen $k{\ddot{o}}nnte$. Grund $daf{\ddot{u}}r$ ist, dass, weil das traditionelle $Lebensgef{\ddot{u}}hl$ nicht in einem Tage gebildet worden ist, $l{\ddot{a}}sst$ sich es nicht vermeiden, dass dieses $Lebensgef{\ddot{u}}hl$ auf alles, was mit dem Leben Zusammenhang steht, einen unmittelbaren Einfluss $aus{\ddot{u}}bt$. Dann kann man sagen, dass das sich $nat{\ddot{u}}rlich$ in der Ansicht zum Spiel widerspiegelt. Aus diesem Urteil wird man in dieser Arbeit den Vertieftseinsbegriff und den Verfremdungsbegriff gegeneinander stellen, und folglich, wenn man die 'Verfremdung' $f{\ddot{u}}r$ einen sonstigen Charakter des Spiels erachten kann, muss man sie auch in Rechnung ziehen, falls man Spielbegriff studieren will.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.3
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• pp.491-499
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• 2019

Recently, there has been increasing demand for power quality in power supply devices. The IEC 61000-3-2 standard requires that the AC / DC power supply for lighting meet the specifications for the power factor (PF) and total waveform distortion (THD). In addition, advanced countries in Europe are regulating the ripple rate as 15 ~ 30% for the flicker phenomenon caused by the change in the amount of foot energy due to the change in current of the output terminal. Therefore, domestic standards and regulations are being updated. This study adopted the Flyback converter to satisfy the PFC standard, and has the circuit first and second insulation function. To reduce the low frequency ripple of the LED current, Flyback, Coupled Inductor, LC parallel resonance filter, LLC resonance filter, and Cuk were simulated by PSIM to mimic each LED driving circuit. A coupled LC resonant circuit with a coupled inductor on the primary side and LC resonance on the secondary side was also proposed for output side ripple reduction.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.11
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• pp.488-496
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• 2018

This study examined the Gangwon Province's current implementation of its elimination of invasive plants and explored a plan to effectively manage invasive plants. The percentage of the distribution of the plants was 39.6% for riverside areas, 23.3% for roadside areas, 12.4% for roadside & riverside areas, and 4.6% for areas around farm land and river banks. To ensure the systematic management of invasive plants, the current study suggests a) developing an invasive plants monitoring and management system; b) reinvigorating the participation of residents, private organizations, and military posts; c) planting of native replacement plants and the conversion of the locations as attractions, and d) nurturing the project for using invasive plants. For policy directions to be pursued based on the results of the study, the following are suggested: a) improving laws and systems regarding invasive plants, b) developing a cooperative system for managing invasive plants, c) implementing the training of civilian professionals, d) implementing the elimination of invasive plants, e) developing replacement plants for cities and counties, f) fostering industries that tap into invasive plants, and g) using the Han River Water System Management Fund for funding and greater efficiency.

• Geomechanics and Engineering
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• v.17 no.4
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• pp.333-342
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• 2019

Geological dynamic hazards during coal mining can be caused by the failure of a composite system consisting of roof rock and coal layers, subject to different loading rates due to different advancing velocities in the working face. In this paper, the uniaxial compression test simulations on the composite rock-coal layers were performed using $PFC^{2D}$ software and especially the effects of loading rate on the stress-strain behavior, strength characteristics and crack nucleation, propagation and coalescence in a composite layer were analyzed. In addition, considering the composite layer, the mechanisms for the advanced bore decompression in coal to prevent the geological dynamic hazards at a rapid advancing velocity of working face were explored. The uniaxial compressive strength and peak strain are found to increase with the increase of loading rate. After post-peak point, the stress-strain curve shows a steep stepped drop at a low loading rate, while the stress-strain curve exhibits a slowly progressive decrease at a high loading rate. The cracking mainly occurs within coal, and no apparent cracking is observed for rock. While at a high loading rate, the rock near the bedding plane is damaged by rapid crack propagation in coal. The cracking pattern is not a single shear zone, but exhibits as two simultaneously propagating shear zones in a "X" shape. Following this, the coal breaks into many pieces and the fragment size and number increase with loading rate. Whereas a low loading rate promotes the development of tensile crack, the failure pattern shows a V-shaped hybrid shear and tensile failure. The shear failure becomes dominant with an increasing loading rate. Meanwhile, with the increase of loading rate, the width of the main shear failure zone increases. Moreover, the advanced bore decompression changes the physical property and energy accumulation conditions of the composite layer, which increases the strain energy dissipation, and the occurrence possibility of geological dynamic hazards is reduced at a rapid advancing velocity of working face.

• Journal of the Korean Society of Radiology
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• v.13 no.3
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• pp.473-479
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• 2019

PET-CT improves performance and reduces the time by combining PET and CT of spatial resolution, and uses CT scan for attenuation correction. This study analyzed PET image evaluation. The condition of the tube voltage and current of CT will be changed using. Uniformity phantom and resolution phantom were injected with 37 MBq $^{18}F$ (fluorine ; 511 keV, half life - 109.7 min), respectively. PET-CT (Biograph, siemens, US) was used to perform emission scan (30 min) and penetration scan. And then the collected image data were reconstructed in OSEM-3D. The same ROI was set on the image data with a analyzer (Vinci 2.54, Germany) and profile was used to analyze and compare spatial resolution and image quality through FWHM and SI. Analyzing profile with pre-defined ROI in each phantom, PET image was not influenced by the change of tube voltage or exposure dose. However, CT image was influenced by tube voltage, but not by exposure dose. When tube voltage was fixed and exposure dose changed, exposure dose changed too, increasing dose value. When exposure dose was fixed at 150 mA and tube voltage was varied, the result was 10.56, 24.6 and 35.61 mGy in each variables (in resolution phantom). In this study, attenuation image showed no significant difference when exposure dose was changed. However, when exposure dose increased, the amount of dose that patient absorbed increased too, which indicates that CT exposure dose should be decreased to minimum to lower the exposure dose that patient absorbs. Therefore future study needs to discuss the conditions that could minimize exposure dose that gets absorbed by patient during PET-CT scan.