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Background and objective: This study was conducted to investigate the effect that a gardening program based on a garden created on a university campus has on problem behaviors of children with developmental disabilities.Methods: The participants were 13 children with developmental disabilities (10 male and 3 female) with an average age of 10.5 years. The study was conducted from August 21 to November 27, 2021 by implementing a gardening program with total 30 sessions held twice a week. The research sites were three types of spaces created for children with developmental disabilities on D University campus: the healing garden, forest trail, and cherry road. Discrete Trial Training (DTT) was applied to the activities when implementing the gardening program, which was used as an intervention to reduce problem behaviors. The assessment tool was the Child Behavior Checklist for Ages 6-18 (CBCL6-18) with which the parents and the primary caregivers assessed changes in problem behaviors.Results: Externalizing behaviors including aggressive behavior and rule-breaking behavior scored 9.9 before the program, 7.6 during the program, and 7.0 after the program (p < .01), and problem behaviors scored 39.3 before the program, 32.9 during the program, and 31.8 after the program (p < .05), showing a significant change.Conclusion: The gardening program on campus could reduce problem behaviors of children with developmental disabilities. Various activities in the garden are considered to have utility value as a social welfare service and education program.

Hydroacoustics has been successfully applied to detect and locate small-to-intermediate submarine tectonic activities infrequently recorded in land-based seismic arrays. However, to extend the utilization of T waves to extract other important earthquake source parameters, such as source strength, the roles of earthquake focal mechanisms, and source depths in T-wave envelopes must be thoroughly understood. We performed 3D numerical modeling considering anisotropic source radiation and realistic scattering in the oceanic crust for two focal mechanisms (normal and strike-slip faults) and three depths (5, 10, and 15 km) to investigate the effect of source radiation and focal depth on abyssal T waves. By analyzing the synthetic T-wave envelopes, we showed that stronger SV-energy radiation from a normal-fault earthquake event generates higher-intensity T waves of the same source magnitude. The anisotropic source radiation of a double-couple source causes azimuthal changes in the shapes of T waves, and deeper earthquakes cause gentle-sloped envelopes; however, the slopes also vary with respect to the azimuths of receivers and focal mechanisms. Temporal changes in the slopes of T-wave envelopes of magmatic swarm events near Wordie Volcano, Bransfield Strait, Antarctic Peninsula, imply that the depth dependency can be utilized to determine relative depths for hydrothermal-vent events or sequenced earthquakes.

Ice melting beneath Antarctic ice shelves is caused by heat transfer through the ice-shelf–ocean boundary layer (IOBL). However, our understanding of the fluid dynamics and thermohaline physics of the IOBL flow is poor. In this study, we utilize a large-eddy simulation (LES) model to investigate ocean dynamics and the role of turbulence within the IOBL flow near the ice front. To simulate the varying turbulence intensities, we imposed different theoretical profiles of the velocity. Far-field ocean conditions for the melting at the ice-shelf base and freezing at the sea surface were derived based on in situ observations of temperature and salinity near the ice front of the Nansen Ice Shelf. In terms of overturning features near the ice front, we validated the LES simulation results by comparing them with the in situ observational data. In the comparison of the velocity profiles to shipborne lowered acoustic Doppler current profiler (LADCP) data, the LES-derived strength of the overturning cells is similar to that obtained from the observational data. Moreover, the vertical distribution of the simulated temperature and salinity, which were mainly determined by the positively buoyant meltwater and sea-ice formation, was also comparable to that of the observations. We conclude that the IOBL flow near the ice front and its contribution to the ocean dynamics can be realistically resolved using our proposed method. Based on validated 3D-LES results, we revealed that the main forces of ocean dynamics near the ice front are driven by positively buoyant meltwater, concentrated salinity at the sea surface, and outflowing momentum of the sub-ice-shelf plume. Moreover, in the strong-turbulence case, distinct features such as a higher basal melt rate (0.153 m yr−1), weak upwelling of the positively buoyant ice-shelf water, and a higher sea-ice formation were observed, suggesting a relatively high speed current within the IOBL because of highly turbulent mixing. The findings of this study will contribute toward a deeper understanding of the complex IOBL-flow physics and its impact on the ocean dynamics near the ice front.

Gram-stain-negative, aerobic and rod-shaped bacterial strains, designated SSM26T and SSM44, were isolated from a sea surface microlayer sample from the Ross Sea, Antarctica. Analysis of the 16S rRNA gene sequences of strains SSM26T and SSM44 revealed a clear affiliation with the genus Pseudomonas . Based on the results of phylogenetic analysis, strains SSM26T and SSM44 showed the closest phylogenetic relationship with the species Pseudomonas sabulinigri KCTC 22137T with the 16S rRNA gene sequence similarity level of 98.5 %. Strains SSM26T and SSM44 grew optimally at 30 °C, pH 7.0–7.5 and 0.5–10.0 % NaCl (w/v). The major cellular fatty acids were C18 : 1 ω7c (31.3–34.9 %), C16 : 0 (15.5–20.2 %), summed feature 3 (C16 : 1 ω7c/C16 : 1 ω6c; 19.5–25.4 %) and C12 : 0 (6.0–9.3 %). The genomic DNA G+C content of each strain was 56.2 mol%. Genomic relatedness analyses based on the average nucleotide identity and the genome-to-genome distance showed that strains SSM26T and SSM44 constituted a single species that was clearly distinguishable from its phylogenetically close relatives. The combined phenotypic, chemotaxonomic, genomic and phylogenetic data also showed that strains SSM26T and SSM44 could be distinguished from validly published members of the genus Pseudomonas . Thus, these strains should be classified as representing a novel species in the genus Pseudomonas , for which the name Pseudomonas neustonica sp. nov. is proposed with the type strain SSM26T (=KCCM 43193T=JCM 31284T=PAMC 28426T) and a sister strain SSM44 (=KCCM 43194=JCM 31285=PAMC 28427).

Terra Nova Bay in Antarctica is a formation region for high-salinity shelf water (HSSW), which is a major source of Antarctic Bottom Water. Here, we analyze spatiotemporal salinity variability in Terra Nova Bay with implications for the local HSSW production. The salinity variations in the Drygalski Basin and eastern Terra Nova Bay near Crary Bank in the Ross Sea were investigated by analyzing hydrographic data from instrumented moorings, vessel-based profiles, and available wind and sea-ice products. Near-bed salinity in the eastern Terra Nova Bay (∼660 m) and Drygalski Basin (∼1200 m) increases each year beginning in September. Significant salinity increases (>0.04) were observed in 2016 and 2017, which is likely related to active HSSW formation. According to velocity data at identical depths, the salinity increase from September was primarily due to advection of the HSSW originating from the coastal region of the Nansen Ice Shelf. In addition, we show that HSSW can also be formed locally in the upper water column ( m) of the eastern Terra Nova Bay through convection supplied by brine from the surface, which is related to polynya development via winds and ice freezing. While the general consensus is that the salinity of the HSSW was decreasing from 1995 to the late 2000s in the region, the salinity has been increasing since 2016. In 2018, it returned to values comparable to those in the early 2000s.

The role of the refreezing effect in the ice shelf–ocean boundary layer (IOBL) flow with a super-cooled, plume beneath the ice shelf is investigated using the large-eddy simulation. To reveal the detailed physical processes and characteristics of the IOBL flow, a model domain is initialized and forced by in situ observations and a comparison is made between two simulations, one with the refreezing effect and one without. The simulated velocity, potential temperature, and salinity field are validated with in situ observations performed in Terra Nova Bay in the western Ross Sea in 2016/2017, confirming that the vertical structures in the simulation results agree well with observations. In particular, it is evident that, when the refreezing effect is considered, the IOBL flow can be more realistically resolved, especially upward advection from the sub-ice shelf plume and the ice front eddy. Beneath the ice shelf, two district regions (the inner and outer regions) are identified based on flow characteristics and the refreezing pattern. In the inner region, stratification and stable conditions are observed with negative momentum flux and low refreezing rates. Meanwhile, in the outer region, high shear impact and unstable conditions with a heat flux of −9 to −52 W m−2 are observed, demonstrating the high refreezing rate and the entrainment of super-cooled water from the sub-ice shelf plume. A total of 94 % of the refreezing events occur in the outer region, with a maximum refreezing rate of 1.86 m yr−1 at the ice front.

The Drygalski Ice Tongue presents an ~80 km long floating obstacle to alongshore flows in the Victoria Land coastal ocean region of the Western Ross Sea. Here we use oceanographic data from near to the tongue to explore the interplay between the floating glacier and the local currents and stratification. A vessel-based circuit of the glacier, recording ocean temperature and salinity profiles, reveals the southwest corner to be the coldest and most complex in terms of vertical structure. The southwest corner structure beneath the surface warm, salty layer sustains a block of very cold water extending to 200 m depth. In this same location there was a distinct layer at 370 m not seen anywhere else of water at ~−1.93°C. The new observations broadly, but not directly, support the presence of a coherent Victoria Land Coastal Current. The data suggest the northward moving coastal current turns against the Coriolis force and works its way anticlockwise around the glacier, but with leakage beneath the glacier through the highly ‘rippled’ underside, resulting in a spatially heterogeneous supply to the Terra Nova Bay Polynya region – an important location for the formation of high-salinity shelf water.

The formation of High-Salinity Shelf Water (HSSW), which is the major source of Antarctic bottom water (AABW), has been observed in Terra Nova Bay (TNB) in Antarctica. We believe a description of the spatio-temporal variation of salinity in TNB would help understand the production of HSSW in the region. Hence, the aim of this study is to investigate salinity variations in the Drygalski Basin (DB) and eastern TNB close to Crary Bank of the Ross Sea. For this, we use the moored and profiled hydrographic data, as well as available wind and sea-ice products. We found that deep-ocean salinity in the eastern TNB (~ 660 m) and DB (~ 1200 m) increases each year starting in September, and large amounts of salinity increase (> 0.04) were observed in 2016 and 2017. According to the velocity data observed at the same depths, the increases in salinity from September were due to the advection of HSSW from the coastal region of the Nansen ice shelf (NIS). The significant increases in salinity are related to the formation of active HSSW, evidence of which can be found from the HSSW properties obtained in February 2017 and March 2018. In addition, we show that HSSW can locally formed in the upper layer (

Tosimulatetheobservationoftheradiationpatternofanearthquake,thedirectsimulationMonteCarlo(DSMC) method is modified by implanting a focal mechanism algorithm. We compare the results of the modified DSMC method (DSMC-2)withthoseoftheoriginalDSMCmethod(DSMC-1).DSMC-2showsmoreorsimilarlyreliableresultscompared to those of DSMC-1, for events with 12 or more recorded stations, by weighting twice for hypocentral distance of less than 80km.Notonlythenumberofstations,butalsootherfactorssuchasroughtopography,magnitudeofevent,andtheanalysis methodinfluencethereliability ofDSMC-2.ThemostreliableresultbyDSMC-2isobtainedbythebestazimuthalcoverage bythelargestnumberofstations.TheDSMC-2methodrequiresshortertimestepsandalargernumberofparticlesthanthose of DSMC-1 to capture a sufficient number of arrived particles in the small-sized receiver.

In December 2015, three hydrophones were moored at the east side of Drygalski Ice Tongue (DIT), seaward of the Nansen Ice Shelf (NIS). On 7 April 2016, the front of the NIS calved into two medium-sized icebergs, presenting a rare opportunity to measure the temporal variation of acoustic signals produced by a large scale ice shelf fracturing event. The acoustic data indicates there are hundreds of short duration, broadband (10–400 Hz) signals throughout the 4-month hydrophone record. We interpret these signals as cryogenic, caused by the cracking of the ice shelves and impacts of nearby sea-ice. The majority of these ice-cracking signals occur during the 21 January to 21 March time frame, two months to two weeks prior to the shelf fracturing observed by satellite on 7 April. Meteorological records of barometric pressure, air temperature, and wind speed show that the day the two icebergs drifted from the NIS coincided with the largest low pressure storm system recorded in the previous 7 months. Our interpretation is the NIS leading edge broke free during the January–March high acoustic energy time period, but the iceberg remained grounded on the seafloor until the low pressure event. The combination of low atmospheric pressure, high winds and high ocean tide, freed the iceberg keel from the seafloor. Strong bio-acoustic signals were also observed on the hydrophones, where the vocalizations of blue whales and leopard seals dominate certain time periods and frequency bands of the long-term acoustic record.

A gravity meter has been used for exploring subsurface mineral resources and monitoring long-period eventssuch as Earth tides. Recently, researchers found several other intriguing features that we could even detect largeteleseismic earthquakes and monitor seismic ambient noise using gravimeters. The zero-length spring suspensiontechnology gives the gPhone (Micro-g LaCoste) excellent low frequency sensitivity, which may have implications forinvestigating much longer-period natural events (e.g., Earth’s hum, tsunami waves, etc.). In this study, we presentpreliminary results through temporary operation of the gPhone at Geumsan in South Korea for 9 months (Nov. 2008-Jul. 2009). The gPhone successfully recorded large teleseismic events and showed a clear seasonal variation of the Doublefrequency microseisms during its operation period.Keywords: gPhone, Teleseismic earthquake, Double frequency microseisms요약: 중력계는 주로 지하 광물자원 탐사 및 지구조석과 같은 장주기 이벤트를 관측하는데 사용되고 있다. 최근 연구자들은 이 중력계를 이용하여 대형 원거리 지진 및 지진상시잡음 관측과 같은 몇몇 새롭고 흥미로운 사실들을 발견하였다. Micro-g LaCoste사의 gPhone에 적용된 zero-length spring suspension 기술은 초저주파 신호도 훌륭히 관측 가능하게하며, 이는 Earth’s hum이나 심지어 대형 지진해일 등을 관측하는데 큰 도움을 줄 수 있음을 시사한다. 이 연구에서는 충남 금산에서 2008년 11월 부터 2009년 7월까지 9개월간 임시로 설치/운영하였던 gPhone 자료를 분석하여 원거리 대형지진관측 및 상시지진잡음의 계절적 변화에 관한 사전결과를 보고하고자 한다.주요어: gPhone, 원거리 지진, 상시지진잡음

Korea Polar Research Institute (KOPRI) has successfully installed two autonomous very broadband three-component seismic stations at the King George Island (KGI), Antarctica, during the 24th KOPRI Antarctic Summer Expedition (2010 ~ 2011). The seismic observation system is originally designed by the Incorporated Research Institutions for Seismology Program for Array Seismic Studies of the Continental Lithosphere Instrument Center, which is fully compatible with the Polar Earth Observing Network seismic system. The installation is to achieve the following major goals: 1. Monitoring local earthquakes and icequakes in and around the KGI, 2. Validating the robustness of seismic system operation under harsh environment. For further intensive studies, we plan to move and install them adding a couple more stations at ice shelf system, e.g., Larsen Ice Shelf System, Antarctica, in 2013 to figure out ice dynamics and physical interaction between lithosphere and cryosphere. In this article, we evaluate seismic station performance and characteristics by examining ambient noise, and provide operational system information such as frequency response and State-Of-Health information.

Korea Polar Research Institute has been operating a broadband seismic station (KSJ1) at the King George Island (KGI), Antarctica, since 2001. Examining ambient seismic noise levels using power spectral analysis for the period of 2006–2008 at the KSJ1, we observed a seasonal pattern at a 4–10 s period. The amplitude of double-frequency (DF) microseism reaches a peak in May. Correlation of the DF energy and its predominant period with significant ocean-wave height and peak wave period models from the WAVEWATCH III and polarization analysis consistently indicate that ocean swell in the Drake Passage is a possible source to excite the DF microseism at the KGI. We also found that the temporal variation of DF amplitude is coincident with the seasonal change of ocean-acoustic ambient noise level around the KGI, which implies that incorporating long-term seismic and hydroacoustic noise information might give us an opportunity to figure out the characteristics of local climate variation near the Antarctic Peninsula.

For the separation of intrinsic () and scattering attenuation () in South Korea, coda observations represented by the multiple-lapse time windows method were numerically simulated using the direct simulation Monte Carlo method. The simulation showed that the depth-dependent velocity model separated by crust and mantle fit better than the uniform velocity model. Under a uniform attenuation assumption, the and total in South Korea represent the lowest values among current global measurements. These low attenuation values can be explained by the inactive seismicity of South Korea corresponding to those of the seismically stable area such as a shield.

Examining seismic envelopes for local earthquakes that occurred in the Gyeongsang Basin, South Korea, we estimated coda Q values in the crust and measured the total scattering coefficients for frequency bands 1–2, 2–4, 4–8, and 8–16 Hz using the Monte Carlo simulation method based on radiative transfer theory. In the seismic envelope synthesis, we assumed acoustic multiple isotropic scattering and adopted a depth-dependent S -wave velocity model that is slightly modified from a receiver function result in the middle of the study region. The estimated total scattering coefficients range from 3.8×10 -3 to at 1–16 Hz, which agrees well with the average values in the crust. These values are corresponding to less than 0.5 of seismic albedo. This result represents that intrinsic absorption is a dominant contributor to the attenuation process for all frequency bands in the Gyeongsang Basin.

Coda envelope reflects heterogeneity in the Earth medium. Examining seismogram envelopes of regional earthquakes over the world in 1–20 s periods for a wide lapse time range up to 2000 s, we classified them focusing on the envelope characteristics around ScS arrivals. We found that coda decay gradient decreases after ScS arrival irrespective of focal depths and epicentral distances on a semi-logarithmic scale plot. Amplitude offset behavior observed in seismic envelopes is an evidence that scattered waves of ScS waves sometimes dominate over scattered S waves and scattered surface waves. Such an offset associated with ScS arrival is not clear for shallow events (

SUMMARY Parameters of earthquake sequences, for instance location and timing of foreshocks and aftershocks, are critical for understanding dynamics of mid-ocean ridge and transform faults. Whole sequences including small earthquakes in the ocean cannot be well recorded by land-based seismometers due to large epicentral distances. Recent hydroacoustic studies have demonstrated that T waves are very effective in detecting small submarine earthquakes because of little energy loss during propagation in Sound Fixing and Ranging channel. For example, an MW 6.2 (2006 March 6, 40.11 ◦ S/78.49 ◦ E) transform-fault earthquake occurred at the Southeastern Indian Ocean Ridge, but National Earthquake Information Center only reported three aftershocks in the first following week. We applied cross-correlation method to hydroacoustic data from the International Monitoring System arrays in the Indian Ocean to examine the whole earthquake sequence. We detected 14 aftershocks and none foreshock for the earthquake and locations of these aftershocks show an irregular pattern. From the observation, we suggest that the feature could be caused by complicated transcurrent plate-boundary dynamics between two overlapped spreading ridges that is possibly explained by the bookshelf faulting model.

Analyzing spectral attenuation of coda waves, we first mapped coda Q- values in the crust over the whole of South Korea. During the period from 1995 to 2004, we selected 574 north-south-component seismograms with epicentral distances less than 100 km from 328 earthquakes with magnitudes between 1.4 and 5.2. We estimated coda Q-values using the single isotropic scattering model at center fre- quencies of 1.5, 3, 6, 9, 12, 15, and 18 Hz, and found significant spatial variation over all frequency ranges and strong frequency dependence of coda Q in the region. The estimated coda Q-value at 1 Hz (Q0) and the g-value ranges are 80-300 and 0.4-1.1, respectively. The values have strong correlation with the regional geology in the Korean peninsula. Low Q0-values are mainly obtained in the regions com- prising sedimentary strata in southeastern South Korea, whereas granite regions in the northern part of South Korea show high Q 0 . The Q 0 -values in the study area agree well with those of the eastern China and Kyushu, western Japan. Furthermore, our g-values are also in good agreement with those of Japan. Online material: Locations of seismometers, list of event-station pairs, and linear regression of QC measurements.