• Title/Summary/Keyword: Time-domain Analysis

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Perception on the Importance of Items on Psychosocial Assessment among Hospice and Palliative Care Social Workers (호스피스·완화의료 사회복지사의 심리사회적 사정항목에 대한 중요도 인식)

  • Kim, Won-Chul;Hwang, Myung Jin
    • Journal of Hospice and Palliative Care
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    • v.17 no.4
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    • pp.259-269
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    • 2014
  • Purpose: This preliminary study is aimed at developing standardized tools for psycho-social assessment of patients in needs for hospice/palliative care. To accomplish the purpose, investigators examined effects of perceptions of social workers on the importance of psycho-social domains of assessment in hospice/palliative care settings. Moreover, investigators paid attention to variances of perceptions of social workers' along with types of institution and credentials of those family settings. Methods: A form of questionnaire was first explored from an initial interview assessment of 10 government-certified hospice care providers and a literature review, second constructed with eight domains and 80 items, and sent by e-mail to 55 institutions and hospitals providing hospice/palliative cares in Korea. Lastly, a total of 31 agencies returned with a completed responses and consent form (56% response rate). SPSS program (version 18.0) was used for data analysis. Results: Study found that social workers perceived patients' family background (m=4.53, 5-point scale) as the most important assessment domain, whereas economic conditions (4.06 point) the least important. Social workers' perception varied by credentials (i.e., license types, training, full-time position, types of care facility). Conclusion: Based upon study findings, investigators can conclude strong needs for developing a assessment tool that measures multiple domains (i.e., psychological, social and ecological aspects) of patients. A standardized assessment tool should be structured with 2 axis (center/core and expanded/peripheral) and tailored for institution type. Second, professional trainings must be provided by strengthening legal institutionalization and fostering qualified social workers with full responsibilities of hospice and palliative care patients.

Distribution of Soil Water Storage at a Hillslope in Sulmachun Watershed (설마천 사면의 토양층 저류량의 분포양상에 관한 연구)

  • Jang, Eun-se;Kim, Sang-Hyun;Lee, Jung-Hoon
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.18 no.2
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    • pp.88-98
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    • 2016
  • The storage variation in the vadose zone at a hillslope is important to understand the hydrological process. This study explores seasonal changes of soil water storage at a hillslope scale. The study was conducted on a hillslope of Beomrunsa, located in the Seolma-cheon river basin in Paju-si, Gyeonggi-do. Using soil moisture measurements through Time Domain Reflectometry (TDR), storage, discharge, and response constant were calculated for all monitoring points on a hillslope between March and November, 2010. This study found that temporal changes in storage are resulted from the rainfall distribution patterns. Analysis of the spatial changes in storage indicated that the soil water storage tends to increase towards the downslope direction. The discharges calculated based on the soil water measurements exhibited a high correlation with observation discharge. The storage response constant was high during the autumn which demonstrates the increased contribution from upslope is responsible for the occurrence of soil water recharge during autumn.

Estimation of Saturation Velocity in Soils During Rainfall using Soil Box Test (모형토조실험을 이용한 강우시 토층의 포화속도 산정)

  • Kim, Chul-Min;Song, Young-Suk;Kim, Hak-Joon
    • The Journal of Engineering Geology
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    • v.25 no.3
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    • pp.377-385
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    • 2015
  • We constructed a model test apparatus to evaluate the dependence of the saturation velocity (Vs) in soils on rainfall intensity (IR). The apparatus comprises a soil box, a rainfall simulator, and measuring sensors. The model grounds (60 cm × 50 cm × 15 cm) were formed by Joomunjin standard sand with a relative density of 75%. The rainfall simulator can control the rainfall intensity to reenact the actual rainfall in a soil box. Time Domain Reflectometer (TDR) sensors and tensiometers were installed in the soils to measure changes in the volumetric water content and matric suction due to rainfall infiltration. During the tests, the soil saturation was determined by raising the groundwater table, which was formed at the bottom of the soil box. [Please check that the correct meaning has been maintained.] The wetting front did not form at the ground surface during rainfall because the soil particles were uniform and the coefficient of permeability was relatively high. Our results show that the suction stress of the soils decreased with increasing volumetric water content, and this effect was most pronounced for volumetric water contents of 20%-30%. Based on a regression analysis of the relationship between rainfall intensity and the average saturation velocity, we suggest the following equation for estimating the saturation velocity in soils: Vsavg (cm/sec) = 0.068IR (mm/hr).

Spatial Distribution of Macropore Flow Percentage and Macroporosities in the Gwangneung Forest Catchment (광릉 산림 소유역에서의 대공극흐름율과 유효대공극부피분율의 공간 분포)

  • Gwak, Yong-Seok;Kim, Su-Jin;Kim, Joon;Lim, Jong-Hwan;Kim, Sang-Hyun
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.9 no.4
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    • pp.234-246
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    • 2007
  • The role of macropore in the hydrological processes is important at the hillslope scale. Developments and distribution of macropores have not been investigated in conjunction with the characteristics of the hillslope such as topography, soil property, and soil moisture. In this study, macropore properties, such as macropore flow and saturation hydraulic conductivity were measured at a hillslope located in Gwangneung Research Forest, Pochun-gun, Gyeonggi-do, South Korea. An intensive field survey provided a refined Digital Elevation Model (DEM) for surface and subsurface topography. Spatial distributions of upslope area and topographic index were obtained through the digital terrain analysis. The total number of monitoring points was 22, and the selected points were distributed along the transect of the digital contour map. Vertical fluxes through macropores were measured using a tension infiltrometer at the depth of 0.1 m from the surface. Spatial and temporal distributions of soil moisture were obtained using an on-line measurement system, TRASE, installed in the study area. Soil moisture for the aforementioned points was measured at 0.1 and 0.3m depths below the surface. The results from tension infiltrometer experiments present that the macropore flows ranged between 21 and 94%, and the measured macroporosities varied from 1.4 to 47%. Macropore flows and macroporosities tended to increase as the measurement location moved to downslope. The ability for water conduction through macropores becomes increasingly developed as the location approaches the outlet of the hillslope.

High School Students' Understanding of Astronomical Concepts Using the Role-playing and Discussion in Small Groups (소집단 역할놀이와 토의를 통한 고등학생들의 천문개념 이해)

  • Jung, Nam-Sik;Woo, Jong-Ok;Jeong, Jin-Woo
    • Journal of The Korean Association For Science Education
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    • v.16 no.1
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    • pp.61-76
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    • 1996
  • The purpose of this study was to apply the instructional strategies for conceptual change prescribed by Posner et al(1982) to the astronomic content domain taught in the elementary and middle school and to analyze the characteristics of students' knowledge revealed in the test before, during and after the instruction. Also, it was to investigate the intercorrelation of cognitive levels, spatial ability and science achievement. The major findings of this study are as follows: 1. Students had a great variety of misconceptions related to the motion of the moon before the instruction, that is, the phases, the names of phases and the cause of changing phases by the moon's orbit about the earth, the moon's appearance and location at the given time, the relative positions of earth, moon and sun during a lunar eclipse, the cause that a full moon is not at the line of node once a month. In the analysis of students' responses concerning the cause of changing phases of the moon and a lunar eclipse, the results indicate that the great majority of students had rote learning rather than meaningful learning in the middle school. 2. Students' reponses during the instruction concerning the changing phases of the moon and the predictive knowledge about the motions of the earth and the moon were analyzed. 1) According to the results of the test given before and after experiment, after discussion, achievement score of the whole of subjects and groups in both preformal and formal cognitive levels appeared to increase linearly. 2) There was no statistically significant differences of achievement scores before and after experiment, after discussion between preformal group and formal group in cognitive levels. 3. Distribution of achievement scores according to the whole of subjects and groups in preformal and formal cognitive levels shows that there was a statistically significant difference between pretest and posttest. 4. Types of conceptual changes concerning the cause of changing phases of the moon that occurred from pretest to posttest were classified as accommodation, incomplete accommodation, assimilation, no change and no model. Six of the seven students starting instruction with alternative frameworks didn't sustain those alternative models throughout instruction. Five of these six students accommodated completely and the last one partially. Seventy-nine percentage of students taking instruction with fragmental models assimilated correct propositions at the end of the instruction. These results suggest that conceptual change model prescribed by Posner et al(1982) has promised the meaningful learning to students taking with fragmental models, especially in cases where students with misconception enter instruction. 5. High correlation between achievement score of simple-recall items and that of written items in pretest and posttest indicates that the higher students got the score in simple-recall items the better they also performed in written items. However, there was no statistically significant differences among cognitive levels, spatial ability and science achievement in the whole of subjects and groups according to the cognitive levels.

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Dynamic Constrained Force of Tower Top and Rotor Shaft of Floating Wind Turbine (부유식 해상 풍력 발전기의 Tower Top 및 Rotor Shaft에 작용하는 동적 하중 계산)

  • Ku, Nam-Kug;Roh, Myung-Il;Lee, Kyu-Yeul
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.25 no.5
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    • pp.455-463
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    • 2012
  • In this study, we calculate dynamic constrained force of tower top and blade root of a floating offshore wind turbine. The floating offshore wind turbine is multibody system which consists of a floating platform, a tower, a nacelle, and a hub and three blades. All of these parts are regarded as a rigid body with six degree-of-freedom(DOF). The platform and the tower are connected with fixed joint, and the tower, the nacelle, and the hub are successively connected with revolute joint. The hub and three blades are connected with fixed joint. The recursive formulation is adopted for constructing the equations of motion for the floating wind turbine. The non-linear hydrostatic force, the linear hydrodynamic force, the aerodynamic force, the mooring force, and gravitational forces are considered as external forces. The dynamic load at the tower top, rotor shaft, and blade root of the floating wind turbine are simulated in time domain by solving the equations of motion numerically. From the simulation results, the mutual effects of the dynamic response between the each part of the floating wind turbine are discussed and can be used as input data for the structural analysis of the floating offshore wind turbine.

Effect of Mahuang on Heart Rate Variability in Adults : a Double-Blind, Placebo-Controlled, Randomized Trial (마황 복용이 정산인의 심박변이도에 미치는 영향에 대한 무작위배정 이중맹검 임상연구)

  • Son, Dong-Hyuk;Hsing, Li-Chang;Kim, Lak-Hyung;Jeong, Seung-Il;Seo, Eui-Seok;Jang, In-Soo
    • The Journal of Korean Medicine
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    • v.28 no.1 s.69
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    • pp.105-116
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    • 2007
  • Objectives : Mahuang (Ephedra sinica), well known as an herbal medicine in the East and West, contains a relatively high percentage of ephedrine known as sympathomimetic alkaloid. We investigated the effects of Mahuang on sympathetic nervous system with heart rate variety (HRV). Time and frequency domain analysis of HRV is a noninvasive technique capable of providing information on autonomic modulation of the sinus node. Methods : We investigated 57 healthy volunteers consisting of 37 subjects in the Mahuang group and 20 subjects in the placebo group. Study form was a randomized, placebo-controlled, double-blind clinical trial. The 37 subjects in the Mahuang group took 3 Mahuang capsules (1 capsule equivalent to 2g herb Mahuang) twice a day at 10 a.m. and 2 p.,., while the 20 subjects in the placebo group took 3 placebo-capsules filled with glutinous rice powder at the same times. Mahuang medicine and placebo medicine were made into opaque capsules. We measured HRV at 3 p.m. 1 or 2 days before medication and at 3 p.m. after medication. Results : Mean-RR and SDNN of the Mahuang group significantly decreased compared with that of the placebo group, but the heart rate of the Mahuang group significantly increased compared with the placebo. HRV-Index, RMSSD and SDSD of the Mahuang group significantly decreased compared with that of the placebo group, but PNN50 of the Mahuang group significantly increased compared with placebo. Ln(TP), Ln(VLF), Ln(LF) and Ln(HF) of the Mahuang group significantly decreased compared with those of the placebo group. There were no significant differences in normalized LF, normalized HF and LF/HF ratio between the Mahuang and placebo groups. Conclusion : The results suggest that Mahuang in healthy adults tends to reduce the autonomic nervous system within the normal range.

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Measurement of two-dimensional vibration and calibration using the low-cost machine vision camera (저가의 머신 비전 카메라를 이용한 2차원 진동의 측정 및 교정)

  • Kim, Seo Woo;Ih, Jeong-Guon
    • The Journal of the Acoustical Society of Korea
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    • v.37 no.2
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    • pp.99-109
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    • 2018
  • The precision of the vibration-sensors, contact or non-contact types, is usually satisfactory for the practical measurement applications, but a sensor is confined to the measurement of a point or a direction. Although the precision and frequency span of the low-cost camera are inferior to these sensors, it has the merits in the cost and in the capability of simultaneous measurement of a large vibrating area. Furthermore, a camera can measure multi-degrees-of-freedom of a vibrating object simultaneously. In this study, the calibration method and the dynamic characteristics of the low-cost machine vision camera as a sensor are studied with a demonstrating example of the two-dimensional vibration of a cantilever beam. The planar image of the camera shot reveals two rectilinear and one rotational motion. The rectilinear vibration motion of a single point is first measured using a camera and the camera is experimentally calibrated by calculating error referencing the LDV (Laser Doppler Vibrometer) measurement. Then, by measuring the motion of multiple points at once, the rotational vibration motion and the whole vibration motion of the cantilever beam are measured. The whole vibration motion of the cantilever beam is analyzed both in time and frequency domain.

Statistical Characteristics of Recent Lightning Occurred over South Korea (최근 남한지역에서 발생한 낙뢰의 통계적 특성)

  • Eom, Hyo-Sik;Suh, Myoung-Seok
    • Journal of the Korean earth science society
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    • v.30 no.2
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    • pp.210-222
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    • 2009
  • Lightning data, observed from total lightning detection system (TLDS) of KMA, for the recent five years (2002-2006) have been analyzed for temporal and spatial characteristics of frequency, intensity, duration, and flash rate. Lightning frequency varies largely with years (most frequent in 2006) and the lightning during the summer accounts for 75% of total flashes and only 0.6% of lightnings strike in cold season. In rainy season (JJAS), the ratio of positive flashes to negative ones is as low as 0.15, but it increases up to 0.98 in February. The seasonal variation of lightning duration is strongly linked with lightning occurrences, whereas flashes rates show weak seasonal variability. In a daily scale, lightning, on average, occurs more often at dawn (2 am, 5-7 am) and in the mid-afternoon (15 pm), and the lightning at dawn (around 5 am) is most intense during the day. The western inland areas md the West/South Sea show high lightning density during JJAS, whereas eastern part and the East Sea exhibit a low density of lightning. Considering the low ratio of positive flashes (0.15) for the whole analysis domain during summer period, Chungnam and Jeonbuk areas have a high ratio of flashes over 0.4. However, these should be analyzed with much caution because weak positive cloud-to-cloud discharges can be regarded as cloud-to-ground flashes. The western inland also exhibits long annual flash hours (15-24). And the W3st Sea has high flash rates as a result of large density and low flash hours. The most frequent time of lightning occurrence over most inland areas lies between mid-afternoon and early-evening, whereas mountainous and coastal areas, and the northern Kyoungki and Hwanghae provinces show the maximum lightning strikes in the morning and at dawn, respectively.

Prediction System of Hydrodynamic Circulation and Freshwater Dispersion in Mokpo Coastal Zone (목포해역의 해수유동 및 담수확산 예측시스템)

  • Jung, Tae-Sung;Kim, Tae-Sik
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.11 no.1
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    • pp.13-23
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    • 2008
  • In coastal region, eutrophication, Do deficit and red tide are frequently occurred by influx of fresh water. When the fresh water containing pollutants is discharged into the sea, the surrounding water is contaminated by dispersion of freshwater flowing into coastal waters. The prediction and analysis about the dispersion process of the discharged fresh water should be conducted. A modeling system using GUI was developed to simulate hydrodynamic flow and fresh water dispersion in coastal waters and to analyze the results efficiently. The modeling module of the system includes a tide model using a finite element method and a fresh water dispersion model using a particle-tracking method. This system was applied to predict the tidal currents and fresh water dispersion in Mokpo coastal zone. To verify accuracy of the hydrodynamic model, the simulation results were compared with observed sea level and time variations of tidal currents showing a good agreement. The fresh water dispersion was verified with observed salinity distribution. The dispersion model also was verified with analytic solutions with advection-diffusion problems in 1-dimensional and 2-dimensional simple domain. The system is operated on GUI environment, to ease the model handling such as inputting data and displaying results. Therefore, anyone can use the system conveniently and observe easily and accurately the simulation results by using graphic functions included in the system. This system can be used widely to decrease the environmental disaster induced by inflow of fresh water into coastal waters.

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