• Journal of Korean Society of Forest Science
• /
• v.104 no.2
• /
• pp.261-266
• /
• 2015

This study was conducted to examine the effect of tree density of Pinus koraiensis forest on the thermal comfort and the physiological response of human body in summer season. As the indicators of thermal comfort were used the predicted mean vote (PMV) and predicted percentage of dissatisfied (PPD), while the heart rate variability was used for the physiological indicator of subjects. The subjects were 15 physically healthy men and women in their 20s ($23.7{\pm}1.7$ years old). The subjects sat in each site to measure HRV for 5 minutes and the thermal comfort of each site was measured. As a results, it was proven by PMV and PPD that the Pinus koraiensis forest with 120% tree density was thermally more comfortable than the Pinus koraiensis forest with 80% tree density. In case of the subjects' physiological response, the Pinus koraiensis forest with 120% tree density showed significantly higher HF of HRV than the Pinus koraiensis forest with 80% tree density and significantly lower LF/HF. Therefore, the findings of this study scientifically proved that the Pinus koraiensis forest with 120% tree density is thermally more comfortable and physiologically more relaxing than the Pinus koraiensis forest with 80% tree density.

• Journal of the Korea Convergence Society
• /
• v.12 no.12
• /
• pp.401-409
• /
• 2021

This study was conducted to investigate the effects of static recovery and dynamic recovery methods on heart rate, blood lactic acid concentration, and blood glucose during recovery after walking at the speed of 80bpm and 130+30bpm upon trekking of forest slopes in Taejo Mountain in Cheonan. 9 men in their 20s and 30s who had no abnormality in walking was subject to this experience. The result of through static recovery and dynamic recovery methods while trekking at the speed of 80bpm and 130+30bpm were analyzed by two-way repeated ANOVA. When there was a significant difference, the repeated method of contrast was applied to compare and analyze. The heart rate at 80bpm condition was significantly different depending on the method(p=.008) and time(p=.000) and there was no significant difference in blood lactic acid concentration for the recovery method(p=.401), but there was a significant difference depending on the time(p=.000). Blood glucose did not show significant difference according to the recovery method(p=.093), and there was significant difference depending on the time of static recovery method(p=.002). The heart rate in 130bpm + 30bpm condition was significantly different depending on to the method(p=.002) and time(p=.000), blood lactic acid concentration was significantly different depending on the method(p=.001) and time(p=.000), and blood glucose concentration was not significantly different between the time(p=090) and the method(p=.721).

• Journal of the Korean Society of Radiology
• /
• v.16 no.2
• /
• pp.131-139
• /
• 2022

The purpose of this study was to insert a pedicle screw into a pig thoracic vertebrae, a general CT scan(Non MAR), and a thoracic axial image obtained with the Metallic Artifact Reduction for Orthopedic Implants (O-MAR) to reduce artifacts. The image obtained by reconstructing the algorithm (Standard, Soft, Bone, Detail) was used using the image J program. Signal to noise ratio(SNR) and contrast to noise ratio(CNR) were compared and analyzed by obtaining measured values based on the given equation. And this study was to investigate tube voltage and algorithm suitable for CT scan for thoracic pedicle screw insertion. As a result, when non-MAR was used, the soft algorithm showed the highest SNR and CNR at 80, 100, 120, and 140 kVp, On the other hand, when MAR was used, the standard algorithm showed the highest at 80 kVp, and the standard and soft algorithms showed similar values at 100 kVp. At 120 kVp, the Soft and Standard algorithms showed similar values, and at 140 kVp, the Soft algorithm showed the highest SNR and CNR. Therefore, when comparing Non-MAR and MAR, even if MAR was used, SNR and CNR did not increase in all algorithms according to the change in tube voltage. In conclusion, it is judged that it is advantageous to use the Soft algorithm at 80, 100, 120, and 140 kVp in Non MAR, the Standard algorithm at 80 and 100 kVp in MAR, and the Soft algorithm at 120 and 140 kVp. This study is expected to serve as an opportunity to further improve the quality of images by using selective tube voltage and algorithms as basic data to help evaluate images of pedicle screw CT scans in the future.

• Journal of the Korean Society of Radiology
• /
• v.17 no.1
• /
• pp.53-62
• /
• 2023

The purpose of this study is to find an optimized imaging technique and evaluate its usefulness by comparing and analyzing the difference in contrast enhancement of lower extremity artery according to the patient's heart rate during lower extremity Computed Tomography Angiography examination. From January 2022 to August 22nd, 139 outpatients who visited Ajou University Hospital and underwent lower extremity angio CT examination were targeted. According to the heart rate, the groups were divided into four groups: A(HR ≤65), B(65 < HR < 80), C(80≤ HR). In addition, among patients with a heart rate of 65 or less, the heart rate was considered, and the scan was divided into D, E, F group with a delay time. The time of arrival of contrast medium and the average value of contrast enhancement were compared and analyzed. As a result of quantitative evaluation, B and C groups with a heart rate of more than 65 times had better HU values in the popliteal artery than A group (HR ≤ 65), and D group showed better HU improvement effects compared to A group (p<0.001). The comparative analysis with other groups was insignificant. The difference in heart rate affected the angiographic intensity of the lower extremities artery. Therefore, it is effective to apply the appropriate test timing for each patient by using the heart rate during the lower extremity angio CT Scan.

• Journal of dental hygiene science
• /
• v.3 no.2
• /
• pp.83-88
• /
• 2003

Patient satisfaction is now recognized as a outcome indicator of health care quality. The objective of this research was to evaluate a patient satisfaction survey instrument specially applicable to dental care, and to examines the reliability and the effect of response biases on reported satisfaction. The acceptability of satisfaction as a quality indicators was qualified by several measurement problems. The patient questionnaire was administered in four different study samples to examine the consistency of data. Cronbach's alpha was used as the measure of internal consistency. A aquiesent bias was found in the sample of 80(20%) respondents. Response biases affacted level of measured satisfaction. Highly acquiesent respondents were older, less well educated than nonaquiesent subject.

• The Journal of the Korea Contents Association
• /
• v.17 no.8
• /
• pp.454-462
• /
• 2017

The purpose of this study was to explore the lonely-death phenomenon and to understand the circumstances surrounding the lonely-death cases among elderly people by examining the articles on such phenomenon and the media reports of such cases. The cases of lonely death reported from 2007 to 2017 were used. Case analysis was conducted, and the news articles that described the lonely death cases were identified using an internet search engine. Forty seven cases were analyzed. Several risk factors emerged from the data obtained, such as economic hardship, chronic illness, mental health problems like alcohol addiction, social isolation, disconnection from family members or the neighborhood, unemployment, single household, unmarried or divorced status, and living in an urban area. Based on the findings, prevention strategies were addressed.

• The Journal of the Petrological Society of Korea
• /
• v.7 no.3
• /
• pp.147-160
• /
• 1998

The Samrangjin Caldera, a trapdoor-type, formed by the voluminous eruption of the silicic ash-flows of the Samrangjin Tuff which is above 630m thick at the northern inside of the caldera and thinnerly 80m at the southern inside. The caldera volcanism eviscerated the magma chamber by a series of explosive eruptions during which silicic magma was ejected to form the Samrangjin Tuff. The explosive eruptions began with phreatoplinian eruption, progressed through small plinian eruption and transmitted with ash-flow eruption. During the ash-flow eruption, contemporaneous collapse of the roof of the chamber resulted in the formation of the Samrangjin caldera, a subcircular depression subsiding above 550m deep. During postcaldera volcanism after the collapse, flow-banded rhyolite was emplaced as cental plug along the central vent and ring dikes along the caldera margins. Subsequently rhyodacite porphyry and dacite porphyry were emplaced along the inner side of the ring dike. After their emplacement, residual magma was emplaced as a hornblende biotite granite stock into the southwestern caldera margin. In the northeastern part, the eastern dikes were cut final intrusions of granodioritic to granitic composition along the fault zone of $^{\circ}$W trend.

• Journal of the Korean Geotechnical Society
• /
• v.30 no.4
• /
• pp.65-80
• /
• 2014

This study conducted Trapdoor tests with actual tunnel shape, investigated the mechanical behavior of ground and loosening load on tunnels, and evaluated the mechanism of progressive failure by numerical simulation. The loosening load sharply decreased initially, but it generally increased and reached the stabilized level exhibiting the arching effect, and loose sand showed relatively higher values than those of dense sand. The shear band started from the tunnel shoulder with $63^{\circ}$ (loose sand) to $69^{\circ}$ (dense sand), and gently curved inward to the ground surface. The widths of shear band formation above the tunnel showed a range from 1.8b to 1.9b (b=Tunnel width), which are similar to those values calculated from existing formular. The vertical height of this shear band for deep tunnel was turned out to be a bit lower than that from existing studies (3.0*Tunnel Height).

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
• /
• v.8 no.3
• /
• pp.1-11
• /
• 2012

Mongolia has three(3) geothermal zones and eight(8) hydrogeothermal systems/regions that are, fold-fault platform/uplift zone, concave-largest subsidence zone, and mixed intermediate-transitional zone. Average temperature, heat flow, and geothermal gradient of hot springs in Arhangai located to fold-fault platform/uplift zone are $55.8^{\circ}C$, 60~110 mW/m2 and $35{\sim}50^{\circ}C/km$ respectively and those of Khentii situated in same zone are $80.5^{\circ}C$, 40~50 mW/m2, and $35{\sim}50^{\circ}C/km$ separately. Temperature of hydrothermal water at depth of 3,000 m is expected to be about $173{\sim}213^{\circ}C$ based on average geothermal gradient of $35{\sim}50^{\circ}C/km$. Among eight systems, Arhangai and Khentii located in A type hydrothermal system, Khovsgol in B type, Mongol Altai plateau in C type, and Over Arhangai in D type are the most feasible areas to develop geothermal power generation by Enhanced Geothermal System (EGS). Potential electric power generation by EGS is estimated about 2,760 kW at Tsenher, 1,752 kW at Tsagaan Sum, 2,928 kW at Khujir, 2,190 kW at Baga Shargaljuut, and 7,125 kW at Shargaljuut.

• The Korean Journal of Zoology
• /
• v.34 no.4
• /
• pp.571-584
• /
• 1991

잉어과(Gyprinidae)의 Zocco속 어류 4종과 Candidia속 어류 1종에 대한 종간 유연관계와 종분화 연대측정 및 이들의 지질학적 분포경로를 밝히기 위하여 한국, 일본 및 대만에서 채집된 개체를 대상으로 전기영동법에 의한 유전자 분석을 하였다. 각 종의 지역별(한국, 일본, 대만) 집단간 유전적 유연관계를 분석한 결과 평균 유전적 근연치는 90% 이상이었다. Z. temmincki의 경우 일본집 단들은 한국의 A-type 집단과는 유연관계가 가까왔으나 한국의 B-type과는 유전적 차이가 현저하러다. Z. PlaD여5의 경우 한국집단과 일본집단사이의 유연관계는 S = 0.852였고, 한국집단과 대만집단 사이는 5 = 0.672, 일본집단과 대만집단 사이는 S = 0.751로서 지리적으로 현저한 차이를 업였다. Z. pochycephalus 3개 집단간의 유전적 근인치는 S = 0.963이었고 Candidia borbota 2개 집단간은 S = 0.946이었다. 종간의 유전적 근연환계를 비교한 결과 Candidia borbota와 Z. temmincki사이는 S = 0.608, Z. pluDpus와 1. pachycephalus사이는 S = 0.612였으나, Z. temmincki와 Z. platypus사이는 S = 0.441, Z. temmincki 와 Z. pochycepholus 사이는 S = 0.350이었고, Z. plotpus와 Condfda barbata사이는 S = 0.328로서 이들 사이에는 현저한 유전적 차이가 있었다. 각 종간의 롱분화 연대를 추산한 결과 이들은 약 480만년 전인 Pliocene 초기에 공통 조상종에서 분화하여 Z. temmincki, Candidia borbato group과 Z. plotypus, Z. pochycepholus group으로 분리되었고 약 260만년 전인 Pliocene 후기에 Z. temminc소와 Candidia borbota로 분화되었다고 추산되며 약 80만년 전인 Pleistocene시기에 남 temmincki B-type에서 h-type이 분화되었다짙 여겨진다. 한편 또 다른 한 단opP은 약 230만년 전인 열iocene후기에 대만 지역의 Z. plotypas에서 Z. pochvcepholus가 분화된 후 현재에 이르렀다고 추정된다. Z. platypus는 약150만년 이전인 초기 Pleistocene시기에 대만지역에서 한국 및 일본집단으로 분리되었다고 보며 이들 한국집단과 일본집단은 약 50만년 전 Pleistocene의 Middle기에 고황하 수계를 거쳐 현재의 분포 상황에 이르렀다고 여겨진다. 한편 대. temmin체과의 B-type에서 저온 적응으로 분화되었다고 추측되는 A-type은 약 20만년 전인 Pleistocene의 Riss기에 역시 고황하 수계를 통하여 한국과 일본으로 분포하여 현재에 이르렀다고 사료된다.