• Journal of Ecology and Environment
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• 제45권1호
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• pp.40-53
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• 2021

The level of soil organic carbon (SOC) fluctuates in different types of forest stands: this variation can be attributed to differences in tree species, and the variables associated with soil, climate, and topographical features. The present review evaluates the level of SOC in different types of forest stands to determine the factors responsible for the observed variation. Mixed stands have the highest amount of SOC, while coniferous (both deciduous-coniferous and evergreen-coniferous) stands have greater SOC concentrations than deciduous (broadleaved) and evergreen (broadleaved) tree stands. There was a significant negative correlation between SOC and mean annual temperature (MAT) and sand composition, in all types of forest stands. In contrast, the silt fraction has a positive correlation with SOC, in all types of tree stands. Variation in SOC under different types of forest stands in different landscapes can be due to differences in MAT, and the sand and silt fraction of soil apart from the type of forests.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2001년도 제22회 KOSCI SYMPOSIUM 논문집
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• pp.82-89
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• 2001

This paper concerns lean gas cyclone combustion system adopting distributed inlets with different velocity to promote ignition and burnout properties. Detailed temperature measurements have been achieved under different operating conditions and flue gas compositions and NOx have been measured. Experimental results show that cyclone combustor provided increasing combustion stability and reduction NOx emission level to negligible level.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2012년도 추계학술대회 논문집
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• pp.75-76
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• 2012

This paper presents an analysis of power losses in three-level T-Type Inverters. The switching loss in different switching frequencies and the conduction loss at different modulation indices and power factors are investigated. Finally, it is shown that the results of analysis coincide with those which resulted from CASPOC software simulation.

• 대한가정학회지
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• 제35권5호
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• pp.131-140
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• 1997

This study was performed to analyze the trends of teen-aged children's daily hassles, the difference of maladjustment according to daily hassles level and to investigate the influence of variables on maladjustment of teen-aged children. The main results of this study were as follows: 1. The mean score of study-related daily hassles were higher than other daily hassles type. 2. Depression, over-anxiousness and delinquency were significantly different according to daily hassles level. 3. The findings of multiple regression analysis shoed different variables in according to maladjustment type.

• 한국사회복지학
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• 제43권
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• pp.358-384
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• 2000

The purpose of this study is to measure the home helpers' knowledge about facts on aging and attitude toward the elderly in Korea, and to find out the variables that may influence their attitude. Four hundred and thirty eight home helpers working in a home help agency were given the questionnaire containing the Kyung San Facts on Aging Quiz to measure the level of knowledge about aging and Yoon (1988)'s scale to find the direction of attitude toward the elderly. The results of this study are analyzed as follows: (1) The home helpers' level of knowledge about aging was 59.1%, which was lower than nurses' level (65.0%) and social workers' level (65.3%). And the paid home helpers' level of knowledge about aging was 61.2%, which was significantly different from the unpaid home helpers' level (57.0%). (2) Using 5 points scale, mean of home helpers' attitude toward the elderly was 2.56 (51.2%), which was different from nurses' attitude (40.6%) and social workers' attitude (62.0%). And the paid home helpers' attitude toward the elderly's action (29.9%) was significantly different from the unpaid home helpers' attitude (32.6%). (3) Using multiple regression analysis, the home helpers' levels of knowledge about aging was the most significant predictor to explain the home helpers' attitude toward the elderly. The other variables that are also statistically significant predictors of the home helpers' attitude were sex, voluntary experience for the elderly, age, city size, and personal experience with the elderly. Especially the significant predictors to explain the paid home helpers' attitude were their levels of knowledge about aging and city size. On the other hand, the significant predictors to explain the unpaid home helpers' attitude were sex and age. Based on the research results, implications for practice and future research are discussed, and education methods for making home helpers' attitude toward the elderly more positive are also suggested.

• The Journal of Korean Physical Therapy
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• 제25권5호
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• pp.297-302
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• 2013

Purpose: This study was conducted in order to investigate the kinematic gait parameter of lower extremities with different gait conditions (level walking, stair, ramp) in hemiplegic patients. Methods: Ten hemiplegic patients participated in this study and kinematic data were measured using a 3D motion analysis system (LUKOtronic AS202, Lutz-kovacs-Electronics, Innsbruk, Austria). Statistical analysis was performed using one-way repeated measure of ANOVA in order to determine the difference of lower extremity angle at each gait phase with different gait conditions. Results: Affected degree of ankle joint in the heel strike phase showed significant difference between level walking and climbing stairs, and toe off phase showed significant difference between level walking and climbing stairs, ramps, and climbing stairs. Affected degree of knee joint showed no significant difference in all attempts. Affected degree of hip joint in the toe off phase showed significant difference between level walking, ramps and stairs, and climbing ramps. Swing phase showed significant difference between sides for level walking and stairs, climbing ramps. Affected ankle joint of heel strike and toe off, and affected hip joint of toe off and the maximum angle of swing phase in the angle was increased. Unaffected side of the ankle joint, knee joint, and hip joint showed a significant increase in walking phase. Conclusion: These findings indicate that compared with level walking, different results were obtained for joint angle of lower extremity when climbing stairs and ramps. In hemiplegia patient's climbing ramps, stairs, more movement was observed not only for the non-affected side but also the ankle joint of the affected side and hip joint. According to these findings of hemiplegic patients when climbing stairs or ramps, more joint motion was observed not only on the unaffected side but also on the affected side compared with flat walking.

• The Journal of Advanced Prosthodontics
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• 제3권4호
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• pp.190-195
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• 2011

PURPOSE. This study evaluated the initial stability of different implants placed above the bone level in different types of bone. MATERIALS AND METHODS. As described by Lekholm and Zarb, cortical layers of bovine bone specimens were trimmed to a thickness of 2 mm, 1 mm or totally removed to reproduce bone types II, III, and IV respectively. Three Implant system (Br${\aa}$nemark System$^{(R)}$ Mk III TiUnite$^{TM}$, Straumann Standard Implant SLA$^{(R)}$, and Astra Tech Microthread$^{TM}$-OsseoSpeed$^{TM}$) were tested. Control group implants were placed in level with the bone, while test group implants were placed 1, 2, 3, and 4 mm above the bone level. Initial stability was evaluated by resonance frequency analysis. Data was statistically analyzed by one-way analysis of variance in confidence level of 95%. The effective implant length and the Implant Stability Quotient (ISQ) were compared using simple linear regression analysis. RESULTS. In the control group, there was a significant difference in the ISQ values of the 3 implants in bone types III and IV (P<.05). The ISQ values of each implant decreased with increased effective implant length in all types of bone. In type II bone, the decrease in ISQ value per 1-mm increase in effective implant length of the Br${\aa}$nemark and Astra implants was less than that of the Straumann implant. In bone types III and IV, this value in the Astra implant was less than that in the other 2 implants. CONCLUSION. The initial stability was much affected by the implant design in bone types III, IV and the implant design such as the short pitch interval was beneficial to the initial stability of implants placed above the bone level.

• 복식
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• 제57권6호
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• pp.172-183
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• 2007

The purpose of this study is to examine the dress and its ornaments of low-level officials shown in Tamna-Sullyeokdo, the paintings of the inspection tour of Jeju Island. The low-level officials Include low-level soldiers-sungjungun, gichigun, foot soldiers, cavalries, gunroe, ilsu, artillerymen, najang, and sawon-, musicians, servants, and kisaengs in government employ. 1. Different types of low-level soldiers tended to wear different kinds of clothes that is worn under an outer garment and to wear different coats and trousers depending on an outer garment. That is, sungjunggun, gichigun, foot soldiers, and cavalries were jeonbok over a jeogori and baji. On the other hand, gunroe, ilsu, artillerymen, and najang were houi or jakui over a jeogori and baji. However, Sawon simply were Jeonbok or armer or they wore Cheolik in formal occasions. 2. Musicians wore a jeonlib, a type of hat, decorated with an ear of barley and a red houi over a Jungchimak, a man's outer coat with large sleeves. Musicians wore colorful red clothes in order to add to the amusement during military trainings or banquets. 3. Servants in government employ had their hair in plaits and wore a jeonbok over a Jungchimak or baji and jeogori. However, when they dance during banquets, they were cheolik and jeonlib decored with/without an ear of barley or red flowers. 4. Gisaengs in government employ wore a gache on their head and wonsam, a woman's full dress during big occasions. They, on the other hand, wore a jeogoli and chima for regular occasions.

• Physical Therapy Rehabilitation Science
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• 제4권1호
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• pp.32-37
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• 2015

Objective: This study was conducted to test the effects of mobile texting and gaming on gait with obstructions under different illumination levels. Design: Cross-sectional study. Methods: Twelve healthy adults aged 20 to 36 years (mean 23.5 years) were tested under six different conditions. All participants used touchscreen smartphones. Testing conditions included: 1) Walking with an obstruction under a bright illumination level; 2) walking with an obstruction with a low level of illumination; 3) walking with an obstruction while texting under a bright illumination level; 4) walking with an obstruction while texting with a low level of illumination; 5) walking with an obstruction while gaming under a bright illumination level; and 6) walking with an obstruction while gaming with a low level of illumination. All participants were asked to text the Korean national anthem by their own phone and play Temple Run 2 using an iPhone 5. Gait variances were measured over a distance of 3 m, and the mean value after three trials was used. A gait analyzer was used to measure the data. Results: Compared to normal gait with obstruction, gait speed, step length, stride length, step time, stride time, cadence while texting and gaming showed significant differences (p<0.05). Differences between the illumination levels included gait speed, step length, stride length, and step time (p<0.05) with no significant differences in stride time and cadence. Conclusions: Dual-tasking using a smartphone under low levels of illumination lowers the quality of gait with obstructions.

• 구강회복응용과학지
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• 제18권4호
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• pp.301-311
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• 2002

The purpose of this study was to compare the distributing pattern of stress on the finite element models with the different vertical bone level of implant fixture. The two kinds of finite element models were designed according to vertical bone level around fixture ($4.0mm{\times}11.5mm$). The cemented crowns for mandibular first and second molars were made. Three- dimensional finite element model was created with the components of the implant and surrounding bone. Vertical loads were applied with force of 200N distributed within 0.5mm radius circle from the center of central fossa and distance 2mm and 4 mm apart from the center of central fossa. Von-Mises stresses were recorded and compared in the supporting bone, fixtures, abutment screws, and crown. The results were as following : (1) In vertical loading at the center circle of central fossa on model 1 and 2, the difference from vertical bone in implant placement did not affect the stress pattern on all components of implant except for crown. (2) With offset distance incerasing and the bone level of implant decreasing, the concentration of stress occured in the buccal side of long crown, around the buccal crestal bone, and on the fixture- abutment interface. As a conclusion, the research showed a tendency to increase the stress on the supporting bone, fixture and screw under the offset loads when the vertical level of bone around fixture was different. Since the same vertical bone bed has more benefits than the different bone bed around fixtures, it is important to prepare a same vertical level of bone bed for the success of implants under occlusal loads.