• Journal of Korean Society for Atmospheric Environment
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• v.22 no.E2
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• pp.69-77
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• 2006

Combined gas and aerosol measurements at a downwind area of the volcanic plume would be essential for helping to access the impact of the volcanic eruption on the local ecosystem and residents. An intensive and the fine time resolution measurement of $SO_2$, sulfate and PM2.5 was made to estimate their distribution in the Kanto area of Japan during the Miyakejima volcanic eruption period. In Tokyo, the 1 hr average $SO_2$ concentration observed before the eruption was 23.9 ppbv, while that of after eruption was 140.4 ppbv. In the Saitama Prefecture, the average concentration of $SO_2$ marked in the present study was two times higher than the average before the volcanic eruption. The PM2.5 mass concentrations in Sitama ranged from 3.8 to $136{\mu}g\;m^{-3}$. Sulfate accounts for $4.4{\sim}39.6%$ of PM2.5 in Sitama. The good correlationship between the concentrations of $SO_2$ and sulfate was obtained. The results of the VAFTAD and HYSPLIT models indicate that $SO_2$, sulfate, and PM2.5 measured in the present study would be expected to be significantly affected by the Miyakejima volcanic plume.

• Journal of the korean academy of Pediatric Dentistry
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• v.45 no.4
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• pp.464-473
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• 2018

The purpose of this study was to investigate the distribution of eruption disturbance and to analyze its causes, treatment methods, and duration of orthodontic traction, based on 703 patients with eruption disturbance who were treated in the pediatric dental clinic of Seoul National University Dental Hospital between July 2011 and June 2016. Eruption disturbance in pediatric patients was most prevalent in the maxillary canine, followed by the maxillary central incisor and maxillary first molar. Eruption disorder of the maxillary canine was more common in females (p < 0.001), whereas the maxillary central incisor (p = 0.009), maxillary first molar (p < 0.001) and mandibular first molar (p = 0.028) were more common in males than females. The most common causes of eruption disturbance were abnormality of the eruption pathway and the presence of obstacles in the pathway. Orthodontic traction was the most prevalent treatment choice for eruption disorder, mostly done for the maxillary central incisors. The duration of orthodontic traction was shorter with younger age (p < 0.001) and lower crown position (p < 0.001). It is important for pediatric patients to detect eruption disorders early through regular checkup, and it is necessary to initiate treatment at an appropriate time with an accurate diagnosis and treatment plan.

• The Bulletin of The Korean Astronomical Society
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• v.38 no.2
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• pp.90.1-90.1
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• 2013

To better understand the physics underlying the eruption of prominences in solar active regions, we studied eruption processes of two active prominences located in the active region NOAA 11261 using multi-wavelength observational data with high temporal and spatial resolution. Specifically, we examined (1) the temporal variation of morphology and plasma properties of the two active prominences, (2) magnetic fields and their evolution on the photospheric surface underneath the prominences, and (3) the time profiles and locations of radio, EUV, and soft/hard X-ray emissions produced by the M9.3 flare related to the prominence eruption. As a result, we found that: (1) a prominence F1 began to erupt and expand as the abrupt and intense EUV brightening occurred in the localized region underneath the western part of F1 at 03:45 UT prior to the peak time of the M9.3 flare, (2) F1 split into two parts: i.e., the western part asymmetrically erupted by producing the M9.3 flare with microwave source motions along the magnetic polarity inversion line between the two flare ribbons, while the eastern part coalesced into a pre-existing prominence F2, (3) F2 became unstable due to the coalescence with the eastern part of F1, and then it partially erupted with clockwise untwisting motions.

• The Journal of the Korean dental association
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• v.25 no.11 s.222
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• pp.1069-1077
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• 1987

Two brothers aged 15 1/6 and 12 2/3 years were diagnosed as Class I malocclusion with ectopic eruption of the upper left central incisor in the elder brother and etopic eruption in the upper right second premolar in the younger. All 4 second molars were extracted at the same time in both brothers. The treatment results were as follows. 1. In the elder brother, the third molars were fully erupted and their angulations were excellent at 3 years post-treatment. 2. In the younger brother, the lower right third molar was mesially erupted and upper third molars were still undergoing eruption at 3 years post-treatment. 3. Assessment of panex films of both brothers at aged 15 showed an earlier eruption of the third molars in the younger brother. 4. A longer post-treatment supervision of the third molars was required in the younger brother. 5. The facial probiles were enhanced and the ectopic eruptions were corrected in both brothers.

• Journal of the korean academy of Pediatric Dentistry
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• v.43 no.1
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• pp.51-59
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• 2016

The purpose of the present retrospective study was to analyze gender, age, awareness, etiology, and treatment choice in patients with failed eruption of the mandibular first molar. Radiographic material and dental records from 67 patients with 74 mandibular first molars with failed eruption treated during the years 2001-2014 were evaluated. As results, the prevalence of mandibular first molar with failed eruption was higher in males than females, and the average awareness age was 9.19 years old. The most common etiological cause was unknown, and the next most common causes were abnormal eruption pathway and odontogenic tumor in order. In this study, it is suggested that more dental education to children about the time of eruption of permanent tooth is required, and the importance of regular dental check-ups is emphasized during mixed dentition.

• Korean Journal of Mineralogy and Petrology
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• v.33 no.3
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• pp.293-305
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• 2020

An eruption of Taal Volcano in the Philippines began on January 12, 2020. The Philippine Institute of Volcanology and Seismology (PHIVOLCS) subsequently issued an Alert Level 4, indicating that "a hazardous explosive eruption is possible within hours to days." It was a phreatic eruption and phreatomagmatic eruption from the main crater that spewed ashes to Calabarzon, Metro Manila, some parts of Central Luzon, and Pangasinan in Ilocos Region, resulting in the suspension of classes, work schedules, and flights. By January 26, 2020, PHIVOLCS observed inconsistent, but decreasing volcanic activity in Taal, prompting the agency to downgrade its warning to Alert Level 3. After February 14, Alert status was set to Level 2 because of overall decreasing trend of volcanic activities, but it does not mean that the threat of an eruption has disappeared. In addition, the Alert Level can be raised to Alert Level 3 if there is a symptom of increasing unrest at any time.

• The Journal of the Petrological Society of Korea
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• v.14 no.4 s.42
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• pp.251-263
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• 2005

Modern volcanoes, Laoheishan and Huoshaoshan, have erupted during $1720\~1721$ in the Wudalianchi volcanic group, NE china. They comprise scoria and spatter cones that consist of potassium-rich phono-tephritic pyroclastic deposits and lavas, and include wide lava flow fields. The Laoheishan scoria cone is a polygenetic multiple volcano that overlaps earlier and later edifices with more complicated internal structures produced in greater scale and in earlier time than the Huoshaoshan. There is a funnel-shaped crater in the center of the later edifice of the Laoheishan scoria cone. The Huoshaoshan spatter cone is a monogenetic simple volcano with a central pit crater. The volcanic sequences indicate eruption processes that followed a repeated pattern that progressed through 5 stages of explosive and effusive eruption including lava fountains and Strombolian eruptions in the Laoheishan, and a recognizable pattern of 2 stages that started with Strombolian eruption and progressed through lava effusion in the Huoshaoshan.

• Journal of the korean academy of Pediatric Dentistry
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• v.48 no.2
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• pp.229-236
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• 2021

Eruption disturbances of the mandibular first molars can cause multiple problems in occlusal development although they are extremely rare. Early diagnosis and treatment are very important to prevent complications associated with eruption disturbances. The present case report describes the treatment of two cases of eruption disturbances of the mandibular first permanent molar. A fixed appliance composed of a cantilever spring with mandibular second deciduous molar as an anchor tooth was used to tract the impacted mandibular first permanent molar. The success of both cases shows that this novel traction appliance can be used to induce the eruption of an impacted mandibular first permanent molar within a short time in patients with intact mandibular second deciduous molar as an anchor tooth.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.23 no.3
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• pp.217-225
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• 2001

Any fracture passing through the socket of a teeth is compounded intraorally, even if the fracture is not displaced and the tooth is firm in its socket. Before the advent of antibiotic therapy the danger of infection in a compounded fracture posed severe problems in treatment. Infection is reduced by antibiotic therapy but prolonged use of antibiotics is not justified in an attempt to save a tooth which might eventually be sacrificed. There is still controversy in the management of third molar in mandibualr angle fracture, particulary in regard to their retention or removal at the time of fracture treatment. So we surveyed the 159 patients who were treated with open reduction of mandibular angle fracture containing third molar in fracture line, and compared with the postoperative infection rate depending on time intervals between injury and operation, eruption state of third molar, non-extraction or extraction of third molar related to eruption state, non-extraction or extraction of third molar related to condiition of third molar and its surrounding periodontium and were to propose treatment guidline of third molar in mandibular angle fracture The results obtained were as follows : 1. There were no statistical significance between the time from injury to operation and postoperative infection. 2. There were no statistical significance between eruption state of third molar and postoperative infection. 3. In case of retention of the third molar, there were no statistical significance between eruption state of third molar and postoperative infection, but in case of extraction, postoperative infection was high rate in complete impacted cases. 4. There were no statistical significance between non-extraction or extraction of third molar and postoperative infection depending on condition of third molar. There are no difference in infection rate statistically according to the time from injury to operation, eruption state and condition of third molar, but retention of third molar revealed lowered infection rate in completely impacted cases. By terms of the manegement of third molar, we should extract or preserve third molar in the line of the mandibular angle fracture according to possibility of infection.

• Korean Journal of Remote Sensing
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• v.33 no.1
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• pp.37-46
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• 2017

Sinabung volcano in Indonesia was formed due to the subduction between the Eurasian and Indo-Australian plates along the Pacific Ring of Fire. After being dormant for about 400 years, Sinabung volcano erupted on the 29th of August, 2010 and most recently on the 1st of November, 2016. We measured the deformation of Sinabung volcano using Advanced Land Observing Satellite/Phased Array type L-band Synthetic Aperture Radar(ALOS/PALSAR) interferometric synthetic aperture radar(InSAR) images acquired from February 2007 to January 2011. Based on multi-temporal InSAR processing, we mapped the ground surface deformation before, during, and after the 2010 eruption with time-series InSAR technique. During the 3 years before the 2010 eruption, the volcano inflated at an average rate of ~1.7 cm/yr with a markedly higher rate of 6.6 cm/yr during the 6 months prior to the 2010 eruption. The inflation was constrained to the top of the volcano. From the 2010 eruption to January 2011,the volcano subsided by approximately 3 cm (~6 cm/yr). We interpreted that the inflation was due to magma accumulation in a shallow reservoir beneath Sinabung. The deflation was attributed to magma withdrawal from the shallow reservoir during the eruption as well as thermo-elastic compaction of erupted material. This result demonstrates once again the utility of InSAR for volcano monitoring.