• Journal of the Korean Association of Geographic Information Studies
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• v.10 no.3
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• pp.40-48
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• 2007

We analyze relation between phytoplankton and marine environment based on data such as water temperature, phytoplankton, zooplankton, nutrient collected from the southern coast of Korea in the summer, 2004. The water temperature range of the study area was $20.5{\sim}31.5^{\circ}C$ and there was formed a water temperature frontal zone from $20.5^{\circ}C$ to $25.0^{\circ}C$ in Geojedo southern coast and Geomundo island. Especially, high density of nutrients were shown in the southern coast of Geojedo in which water temperature frontal zone was formed strongly, the concentration of chlorophyll-a which is appeared at the highest rate among the phytoplankton pigments was shown more than $0.4{\mu}g/L$ in the inside of frontal zone and zooplankton biomass was than $500mg/m^2$ in that area.

• Journal of Korean Institute of Industrial Engineers
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• v.26 no.2
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• pp.88-94
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• 2000

For efficient operation, vital hand controls must be easily controlled by the operator from his or her normal working position. The primary working area based on the operator-perceived working comfort was developed to serve as a design guideline to the control panel layout. Six male and four female subjects voluntarily participated in the experiment in which working comfort was measured for two types of controls - knob and lever. The operator-perceived working comfort was examined for the frontal and sagittal distances from the body center and the slope of a work surface. The response surface methodology using a central composite design was employed to develop a prediction model for operator's working comfort on each type of controls. The proposed working areas based on the actual working comfort of an operator avoided the dichotomy that considers only the reachability of control devices, and showed a distinct shape, when compared to the existing normal working areas following the Farley's concept. It was shown that the distance from the body to control devices and the slope of a work surface have a quadratic relationship to the working comfort, and that the most comfortable area for seated tasks is located at the distance of about 2∼4 cm in the sagittal direction and about 42∼43 cm in the frontal direction from the shoulder, respectively. It was also found that the working comfort varies within the working area even at the positions with an equal distance from the body. It is expected that the isocomfort working area generated in the study will be used as a useful guideline for control panel layout.

• Journal of the Korean Society of Marine Environment & Safety
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• v.12 no.1 s.24
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• pp.1-8
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• 2006

To investigate the variation of marine environments due to set up of artificial structure, we carried out field observations. High temperature and salinity waters near the south frontal area were distributed clearly in the southeastern part of study area during summer season The variation of current structure was also occurred around study area where artificial structure set up. In 2005 after set up of artificial structure, the nutrient concentration increased greater than that in 2002 before set up artificial structures. To illustrate the characteristics of marine environment due to set up of artificial structure, quantitative analyses on the effect of artificial structure are important.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.3
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• pp.1707-1714
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• 2015

The neural bases underlying within or between-language picture naming was investigated by using event-related fMRI. The present suudy explorered the following two goals: The first is to compare cortical activation areas relevant to naming process in native and foreign language, and to decide whether the activation pattern of the foreign word will be the same as native words or not. The next is to find the cerebral areas involved only in alternating language switching between native and foreign language condition. Differential activation patterns were observed for language switching against one-language. Both naming tasks all activated the left inferior frontal gyrus (LIFG) as expected. However the differences in naming between languages were reflected in the activation amount of the LIFG, namely more activation in naming the native language than the foreign language. Especially, naming of the foreign word from English showed the similar area and size in activation with native language suggesting that the process of borrowed noun resembles that of native common noun. And the language switching between languages newly activated the right middle frontal gyrus as well as the left inferior frontal areas. The right middle frontal gyrus engagement in switching conditions obviously identified that right hemisphere is recruited in code switching possibly with respect to meta-cognition controlling language index at a subconscious level.

• Journal of the Ergonomics Society of Korea
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• v.33 no.5
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• pp.377-386
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• 2014

Objective: In this study, we used resting-state fMRI data to map differences in functional connectivity between a comprehensive set of 8 distinct cortical and subcortical brain regions in healthy controls and Internet addicts. We also investigated the relationship between resting state connectivity strength and the level of psychopathology (ex. score of internet addiction scale and score of Barratt impulsiveness scale). Background: There is a lot of evidence of relationship between Internet addiction and impaired inhibitory control. Clinical evidence suggests that Internet addicts have a high level of impulsivity as measured by behavioral task of response inhibition and a self report questionnaire. Method: 15 Internet addicts and 15 demographically similar non-addicts participated in the current resting-state fMRI experiment. For the connectivity analysis, regions of interests (ROIs) were defined based on the previous studies of addictions. Functional connectivity assessment for each subject was obtained by correlating time-series across the ROIs, resulting in $8{\times}8$ matrixs for each subject. Within-group, functional connectivity patterns were observed by entering the z maps of the ROIs of each subject into second-level one sample t test. Two sample t test was also performed to examine between group differences. Results: Between group, the analysis revealed that the connectivity in between the orbito frontal cortex and inferior parietal cortex, between orbito frontal cortex and putamen, between the orbito frontal cortex and anterior cingulate cortex, between the insula and anterior cingulate cortex, and between amydgala and insula was significantly stronger in control group than in the Internet addicts, while the connectivity in between the orbito frontal cortex and insula showed stronger negative correlation in the Internet addicts relative to control group (p < 0.001, uncorrected). No significant relationship between functional connectivity strength and current degree of Internet addiction and degree of impulsitivy was seen. Conclusion: This study found that Internet addicts had declined connectivity strength in the orbitofrontal cortex (OFC) and other regions (e.g., ACC, IPC, and insula) during resting-state. It may reflect deficits in the OFC function to process information from different area in the corticostriatal reward network. Application: The results might help to develop theoretical modeling of Internet addiction for Internet addiction discrimination.

• The Journal of Korean Physical Therapy
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• v.22 no.5
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• pp.109-115
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• 2010

Purpose: This study was to delineate the structural change of neural pathway after sequential motor learning using diffusion tensor imaging (DTI). Methods: The participants were 16 healthy subjects, which were divided by training (n=8) and control (n=8) group. The task for the training was the Serial Reaction Time Task (SRTT) which was designed by Superlab program. When the 'asterisk' shows up in the 4 partition spaces on the monitor, the subject presses the correct response button as soon as possible. The training group participated in the training program of motor learning with SRTT composed of 24 digits pattern in one hour per daily through 10 days during 2 weeks. Results: In the behavioral results the training group showed significant changes in the increase of response number and the reduction of response time than those of the control group. There was significant difference in the left inferior frontal area in the fractional anisotropy (FA) map of the training group in DTI analysis. Conclusion: Motor sequential learning as like SRTT may be needed to the learning of language and visuospatial processing and may be induced for the experience-dependent structural plasticity during short period.

• Journal of Korean Tunnelling and Underground Space Association
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• v.7 no.4
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• pp.313-321
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• 2005

Drag coefficient is one of the critical design factors to quantify the piston effect in vehicle tunnels. Several problems are raised on the drag coefficient currently applied for the ventilation system design; unverified adoption of the projected frontal area of the vehicle from the foreign study in the past, and lack of consideration for the slip-streaming effect. This study aims at better estimation of the traffic-induced ventilation force in the local tunnels. Values for the projected frontal area of the vehicles running on the local roads at present are proposed and results of an extensive CFD study are studied on the slip-streaming effects in various traffic conditions to quantify $K_{blockage}$ and the drag coefficient in the domestic tunnels.

• 한국해양학회지
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• v.26 no.3
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• pp.223-241
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• 1991

In order to study the formation and structure of tidal fronts and their influence on the distribution and productivity of phytoplankton in the outer of Kyonggi Bay, analyses on the water temperature data from 1977 to 1986 and 3 surveys from 1981 to 1986 were carried out in the mid0eastern coast of the Yellow Sea. Temperature gradients and dissolved oxygen gradients were implied that the tidal fronts are formed at the outer of the Kyonggi Bay along the western side of Tae-An peninsula from spring to summer. the formations of tidal fronts in this study area influence the distribution of phytoplankton and primary productivity. The standing stocks, chlorophyll concentrations and primary productivity of phytoplankton in the frontal area are higher than those of the outer stratified waters and the inner coastal mixed waters. These high production in the frontal area are resulted from good light condition and rich nutrient within the water columns. With a boundary of frontal area, there are relatively high chlorophyll concentrations and primary productivity in the coastal mixed waters while there are low chlorophyll concentrations and relatively high primary productivity in the stratified waters. These relatively high primary productivity in the outer area are resulted from the high potential production by nanoplankton in the surface layer and the high production of tychopelagic diatoms under the thermocline with the deep transparency.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.29 no.2
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• pp.411-416
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• 1999

Purpose : This study was done to evaluate the absorbed doses in organs of the head and neck for the conventional temporomandibular joint tomography. Materials and Methods : Dosimetry was performed with 32 LiF thermoluminescent dosimeters, which were placed in a tissue-equivalent phantom when the temporomandibular joint was examined by both lateral and frontal temporomandibular joint tomography. Results : For lateral tomography, parotid gland and preauricular area towards tube showed relatively high absorbed dose of 1056.9 μGy and 519.9 μGy respectively. For frontal tomography, the two largest absorbed doses were 259.2 μGy in orbit towards tube and 212.0 μGy in lens towards tube. Conclusion : Conventional temporomandibular joint tomography showed relatively low absorbed doses on critical organs. Thus, responsible use of it may not be limited.

• Journal of Korean Neurosurgical Society
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• v.56 no.6
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• pp.509-512
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• 2014

Primary intraosseous meningioma is a rare tumor, and atypical pathologic components both osteolytic lesion and dura and soft tissue invasion is extremely rare. A 65-year-old woman presented with a 5-month history of a soft mass on the right frontal area. MR imaging revealed a 4 cm sized, multilobulated, strongly-enhancing lesion on the right frontal bone, and CT showed a destructive skull lesion. The mass was adhered tightly to the scalp and dura mater, and it extended to some part of the outer and inner dural layers without brain invasion. The extradural mass and soft tissue mass were totally removed simultaneously and we reconstructed the calvarial defect with artificial bone material. The pathological study revealed an atypical meningioma as World Health Organization grade II. Six months after the operation, brain MR imaging showed that not found recurrence in both cranial and spinal lesion. Here, we report a case of primary osteolytic intraosseous atypical meningioma with soft tissue and dural invasion.