• Title/Summary/Keyword: Environmental sample

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The Effects of Learning Transfer on Perceived Usefulness and Perceived Ease of Use in Enterprise e-Learning - Focused on Mediating Effects of Self-Efficacy and Work Environment - (지각된 유용성과 사용용이성이 기업 이러닝 교육의 학습전이에 미치는 영향에 관한 연구 -자기효능감과 업무환경의 매개효과를 중심으로-)

  • Park, Dae-Bum;Gu, Ja-Won
    • Management & Information Systems Review
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    • v.37 no.3
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    • pp.1-25
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    • 2018
  • This research performed the empirical test for the effects of learning transfer on perceived usefulness, perceived ease of use, self-efficacy and work environment using 390 employees who have experienced e-learning in domestic and foreign companies. Analyzed the mediating effects of self-efficacy and work environment in addition to direct effect of each factor on learning transfer. The results showed that perceived usefulness and perceived ease-of-use of e-learning learner had a positive(+) effect on self-efficacy and a positive influence on supervisor and peer support and organizational climate. Self-efficacy showed a positive effect on learning transfer, and supervisor support, peer support and organizational climate had a positive influence on learning transfer as well. Perceived usefulness also had a positive effect on learning transfer. However, perceived ease-of-use had no significant effect on learning transfer. As a result of the mediating effect analysis, self-efficacy and work environment were analyzed to have mediating effects between perceived usefulness, perceived ease of use, and learning transfer. The implications of this study are as follows. First, this study designed a new research model that reflects factors influencing the effect of learning transfer on acceptance of e-learning that is common in corporate education. It has derived a research model of perceived usefulness and perceived ease-of-use, which were used as mediating variables for external characteristics factors, as independent variables, using self-efficacy and work environment as mediating variables, which were studied as external factors. Second, most of the studies on technology acceptance model and learning transfer are conducted in a single country. The reliability was enhanced by testing the study models using different samples from 26 countries. Third, perceived usefulness and ease-of-use in existing studies have been considered as key determinants of acceptance intention and learning transfer. This study explored the mediating effects of learner and environmental factors on the accepted information technology and strengthened and supplemented the path of learning transfer of perceived usefulness and ease-of-use. In addition, based on the sample analysis of various countries used in this study, it is expected that future international comparative studies will be possible.

Actual Vegetation and Structure of Plant Community in Daegwallyeong Ranch, Gangwon-do (Province) (강원도 대관령 목장 현존식생 및 식물군집구조)

  • Noh, Tai-Hwan;Han, Bong-Ho;Kim, Jong-Yup;Lee, Min-Young;Yoo, Ki-Joon
    • Korean Journal of Environment and Ecology
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    • v.27 no.5
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    • pp.579-591
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    • 2013
  • This study was carried out to investigate the actual vegetation, the structure of plant community, and ecological succession sere of forest ecosystem in temperate northern climate zone, Daegwallyeong Ranch, Gangwon-do (Province) and to offer the basic data for planning of the forest managemant. As a result of analysis of actual vegetation, vegetation types divided into 56types and the area of survey site was $19,397,361m^2$. The ratio of vegetation type dominated by Quercus mongolica forest was 39.1%, primary grassland was 24.7%, Quercus mongolica-Deciduous broad-leaved forest was 11.3%. Twenty eight plots (size is $20m{\times}20m$) were set up and the results analyzed by DCA which in one of the ordination technique showed that the plant communities were divided into six groups which area community I (Pinus densiflora-Quercus mongolica community), community II (Quercus mongolica-Pinus densiflora community), community III (Quercus mongolica community), community IV (Quercus mongolica-Deciduous broad-leaved community), community V (Deciduous broad-leaved community), community VI (Sorbus alnifolia community). The age of community Iwas ranged from 57 to 62 years old, that of community IIwas ranged from 41 to 77 years old, community III was ranged from 47 to 108 years old, community IV was ranged from 47 to 82 years old, community V was 47 years old, community VI was 55 years old, thus we supposed that the age of the study site is about from 41 to 108 years old. The Ecological succession is predicted from Pinus densiflora community to Quercus mongolica community and Deciduous broad-leaved were distributed in the center of the valley in Daegwallyeong Ranch. According to the index of Shannon's diversity (unit: $400m^2$), community IV was ranged from 0.8203 to 1.1439, community III was ranged from 0.8019 to 1.1375, community V was 1.0993, community I was ranged from 0.9475 to 1.0797, community II was ranged from 0.6896 to 1.0324, community VI was 0.9909.

Studies on the Hardness of Woods (목재(木材)의 경도(硬度)에 관(關)한 연구(硏究))

  • Hong, Soon-Il;Lee, Won Yong
    • Journal of Forest and Environmental Science
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    • v.8 no.1
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    • pp.21-33
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    • 1992
  • This study was performed to investigate the hardness of wood related to the wood surface, sap and heartwood, early and latewood, specific gravity, annual ring width and moisture content on major Korean tree species such as Pinus koraiensis, Abies holophylla, Larix leptolepis and Quercus valiabilis. The results were summarized as follows: 1. The arithmetic mean values of wood hardness on cross section were respectively $8.0kg/mm^2$ on Quercus valiabilis, $7.4kg/mm^2$ on Larix leptolepis, $5.1kg/mm^2$ on Pinus koraiensis and $4.7kg/mm^2$ on Abies hollophylla. 2. Generally hardness of wood on cross section was greater than the others and the proportion of cross section hardness to radial was respectively 2.8 on Quercus valiabilis, 2.6 on Larix leptolepis, 3.8 on Pinus koraiensis, and 4.1 on Abies holophylla and that proportion was tend to be decrease as specific gravity increased. 3. It was recognized that the hardness of sap and heartwood was different from each of the tree species and generally heartwood hardness was somewhat greater than sapwood. 4. Generally latewood hardness with in a ring was greater than earlywood and the proportion of earlywood hardness to latewood decreased as specific gravity increased. 5. The relations between hardness of wood and specific gravity show a high positive correlation on all sample tree species. 6. The values of hardness decreased with increasing annual ring width. 7. Hardness of wood on Abies holophylla was greatest in oven dried wood and it was decreased as moisture content increased, but not changed with moisture content abve F.S.P.. The proportion of oven dried wood hardness to green are respectively 3.0 on cross, 2.4 on radial and 1.9 on tangential section.

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Catalytic Spectrophotometry for the Determination of Manganese at Trace Levels by a Novel Indicator Reaction (새로운 지시약 반응에 의해 극미량 수준의 망간 측정을 위한 촉매 반응의 분광 광도 측정법)

  • Gurkan, Ramazan;Caylak, Osman
    • Journal of the Korean Chemical Society
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    • v.54 no.5
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    • pp.556-566
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    • 2010
  • A new kinetic spectrophotometric method is developed for the measurement of Mn(II) in natural water samples. The method is based on the catalytic effect of Mn(II) with the oxidation of Gallocyanin by $KIO_4$ using nitrilotriacetic acid (NTA) as an activation reagent at 620 nm. The optimum conditions obtained are $4.00{\times}1^{-5}\;M$ Gallocyanin, $KIO_4$, $1.00{\times}10^{-4}\;M$ NTA, 0.1 M HAc/NaAc buffer of pH = 3.50, the reaction time of 5 min and the temperature of $30^{\circ}C$. Under the optimum conditions, the proposed method allows the measurement of Mn(II) in a range of $0.1\;-\;4.0\;ng\;mL^{-1}$ and with a detection limit of down to $0.025\;ng\;mL^{-1}$. The recovery efficiency in measuring the standard Mn(II) solution is in a range of 98.5 - 102%, and the RSD is in a range of 0.76 - 1.25%. The newly developed kinetic method has been successfully applied to the measurement of Mn(II) in both some environmental water samples and certified standard reference river water sample, JAC-0031 with satisfying results. Moreover, few cations and anions interfere with the measurement of Mn(II). Compared with the other catalytic-kinetic methods and instrumental methods, the proposed kinetic method shows fairly good selectivity and sensitivity, low cost, cheapness, low detection limit and rapidity. It can easily and successfully be applied to the real water samples with relatively low salt content and complex matrices such as bottled drinking water, cold and hot spring waters, lake water, river water samples.

Enhancement of the Working Capacity and Selectivity Factor of Calcium-Exchanged Y Zeolites for Carbon Dioxide Pressure Swing Adsorption (이산화탄소 압력순환흡착을 위한 칼슘 이온교환 Y 제올라이트의 작업용량과 선택계수 향상)

  • Kim, Moon Hyeon
    • Clean Technology
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    • v.24 no.1
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    • pp.41-49
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    • 2018
  • Y zeolites with different extra-framework cations, such as $Na^+$, $N^+$, $Ca^{2+}$, and $Cu^{2+}$, with different charge and ionic radius have been investigated to greatly enhance a working capacity (W) of $CO_2$ adsorption at $25^{\circ}C$ and a $CO_2/CO$ selectivity factor (S). A sample of NaY with a very small amount of 0.012% $Ca^{2+}$ was fully reversible for seven times repeated $CO_2$ adsorption/desorption cycles, thereby forming no surface carbonates unlikely earlier reports. Although at pressures above 4 bar, 2.00% CaY, 1.60% CuY and 1.87% LiY all showed a $CO_2$ adsorption very similar to that measured for NaY, they gave a significant decrease in the adsorption at lower pressures, depending on the metal ion. At 0.5 ~ 2.5 bar, the extent of $CO_2$ adsorption was in the order NaY > 1.60% CuY > 2.00% CaY > 1.87% LiY. All the $Na^+-based$ metals-exchanged zeolites have a FAU (faujasite) framework and a Si/Al value near 2.6; thus, there is no discernible difference in the framework topology, framework chemical compositions, effective aperture size, and channel structure between the zeolite samples. Therefore, the distinctive behavior in the adsorption of $CO_2$ with a character as a weak Lewis acid is associated with the site basicity of the zeolites, and the interaction potentials of the cations. Different trend was shown for a CO adsorption due to weaker quadrupole interactions. Adsorption of $CO_2$ and CO on samples of CaY with 0.012 to 5.23% Ca disclosed a significant dependence on the Ca loading. The $CO_2$ adsorption increased when the cation exists up to ca. 0.05%, while it decreased at higher Ca amounts. However, values for both W and S could greatly increase as the bare zeolite is enriched by $Ca^{2+}$ ions. The 5.23% CaY had $W=2.37mmol\;g^{-1}$ and S = 4.37, and the former value was comparable to a benchmark reported in the literature.

Measuring Economic Values of Amenity Services from Urban Greenspaces in the Seoul Metropolitan Area Using Choice Experiments (선택실험을 이용한 서울 도시녹지 어메니티의 경제가치 평가)

  • Choi, Andy S.;Eom, Young Sook
    • Environmental and Resource Economics Review
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    • v.27 no.1
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    • pp.105-138
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    • 2018
  • This paper reports novel empirical results of a choice experiment that elicited the economic values that residents in the Seoul metropolitan area place on the amenity services realized from the landscape views and accessibilities to urban green spaces (i.e., mountains, rivers and urban parks). The 1,000 respondents in the sample were divided into two residential of housing types (apartments vs. houses) and occupancy types (owners vs. tenants). Residents living in apartments are willing to pay an average of 28% (5.0 million KRW per year) above the current housing prices per household for a mountain view, compared to an apartment view from their living room. Their willingness to pay values are about 22% (4.0 million KRW per year) and 10% (1.8 million KRW per year) respectively for a river view and a urban park view. Economic benefits of having access (i.e., a 10 minutes working distance) to mountains, rivers and urban parks are estimated to be an average of 16% (2.9 million KRW per year), 20% (3.6 million KRW per year) and 18% (3.2 million KRW per year), respectively, above the current housing prices per household. On the other hand, access benefits for those residing in houses are 18% (4.7 million KRW per year), 16% (4.1 million KRW per year) and 22% (5.6 million KRW per year) per household, respectively. They are also willing to pay an average of 35% (8.9 million KRW per year) above the current housing prices for keeping or having a garden or vegetation bed. Furthermore, a strong "greenspace premium" is centered around the three Gangnam districts for house-dwellers, whereas it is areas of "new real estate boom" for apartment dwellers.

The Assessment on Health Status of Workers by using HPLP and Sa-sang Constitutional Questionnaire (HPLP와 사상체질설문(四象體質說問)을 이용(利用)한 근로자(勤勞者)들의 건강상태(健康狀態) 평가(評價))

  • Choi Mun-Il;Lee Eun-Kyoung;Kwon So-Hee;Ko Kwang-Jae;Seo Byeong-Yun;Jeoung Jae-Yeal;Jahng Doo-Sub;Song Yung-Sun;Lee Ki-Nam
    • Journal of Society of Preventive Korean Medicine
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    • v.5 no.1
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    • pp.41-56
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    • 2001
  • Overview: The purpose of this study was to evaluate the determinants on the correlation between constitution and health promoting lifestyle profile on the workers. Also, the questionnaire on the HPLP (health promoting lifestyle profile) of Walker(1987) and Sa-sang constitution of Lee(l894) were utilized Methods: Data from a representative sample of 652 workers were analyzed Pearson's chi-square test analysis was utilized to test the explanatory causal model and to determine the direct and indirect effects of independent variables on quality of life. Results: Constitutional distribution among exposed group, were Tae-eum In(43.7%), So-eum In(33.6%), and So-yang In(22.7%). The degree of the subjects practicing health promoting lifestyle, on a scale of 1 to 4, is an average of 2.62, personal relations 2.94, self-realization 2.86, stress management 2.71, nutrition 2.68, responsibility for health 2.37, and exercise 2.21, with personal relations earning the highest points and exercise the lowest As for factors influencing health promoting lifestyle, there is significant difference between sex and age. That is female and higher age. On the difference between constitution and health promoting lifestyle, Tae-eum In is the highest all area except personal relations. So-eum In is the lowest all area except responsibility for health. Conclusions: Tae-eum In totally do health promoting lifestyle well but So-eum In relatively not. On the Study we used the HPLP(health promoting lifestyle profile) on the premise that each person's daily life, the attitude and the practice level to the health have an influence on the health. So in the constitution there is a little differences in the consideration and the practice level and health condition will be different. On this study we finish up by knowing about the health promoting lifestyle. But on next time we will have to go on studying about the sign and the comparison with the result of western and oriental medical health examination to the each constitution on carrying out continuously oriental medical health examination.

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A Study on Fall Accident (1개 종합병원 환자의 낙상에 관한 조사)

  • Lee, Hyeon-Suk;Kim, Mae-Ja
    • The Korean Nurse
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    • v.36 no.5
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    • pp.45-62
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    • 1998
  • The study was conducted from November 1995 to May 1996 at the one general hospital in Seoul. The total subjects of this study were 412 patients who have the experience of fall accident, among them 31 was who have fallen during hospitalization and 381 was who visited emergency room and out patient clinic. The purposes of this study were to determine the characteristics, risk factors and results of fall accident and to suggest the nursing strategies for prevention of fall. Data were collected by reviewing the medical records and interviewing with the fallers and their family members. For data analysis, spss/pc+ program was utilized for descriptive statistics, adjusted standardized $X^2$-test. The results of this study were as follows: 1) Total subjects were 412 fallers, of which 245(59.5%) were men and 167(40.5%) were women. Age were 0-14 years 79(19.2%), 15-44 years 125(30.4%), 45-64 years 104(25.2%), over 65 years 104(25.2%). 2) There was significant association between age and the sexes ($X^2$=39.17, P=0.00). 3) There was significant association between age and history of falls ($X^2$=44.41. P= .00). And history of falls in the elderly was significantly associated with falls. 4) There was significant association with age and medical diagnosis ($X^2$=140.66, P= .00), chief medical diagnosis were hypertension(34), diabetis mellitus(22), arthritis(11), stroke(8), fracture(7), pulmonary tuberculosis(6), dementia(5) and cataract(5), 5) There was significant association between age and intrinsic factors: cognitive impairment, mobility impairment, insomnia, emotional problems, urinary difficulty, visual impairments, hearing impairments, use of drugs (sedatives , antihypertensive drugs, diuretics, antidepressants) (P < 0.05). But there was no significant association between age and dizziness ($X^2$=2.87, P=.41). 6) 15.3% of total fallers were drunken state when they were fallen. 7) Environmental factors of fall accident were unusual posture (50.9%), slips(35.2%), trips (9.5%) and collision(4.4%). 8) Most of falls occurred during the day time, peak frequencies of falls occurred from 1pm to 6pm and 7am to 12am. 9) The places of fall accident were roads(22.6%), house-stairs 06.7%), rooms, floors, kitchen (11.2%), the roof-top, veranda, windows(10.9%), hospital(7.5%), ice or snowy ways(5.8%), bathroom(4.9%), playground, park(4.9%), subway-stairs(4.4%) and public-bathrooms (2.2%). 10) Activities at the time of fall accident were walking(37.6%), turning around or reaching for something(20.9%), going up or down stairs09.2%), exereise, working07.4%), up or down from a bed(2.7%), using wheelchair or walking aids, standing up or down from a chair(2.2%) and standing still(2.2%). 11) Anatomical locations of injuries by falls were head, face, neck(31.3%), lower extremities (29.9%). upper extremities(20.6%), spine, thorax, abdomen or pelvic contents(l1.4%) and unspecified(2.9%). 12) Types of injures were fracture(47.6%), bruises03.8%), laceration (13.3%), sprains(9.0%), headache(6.6%), abrasions(2.9%), intracranial hemorrage(2.4%) and burns(0.5%). 13) 41.5% of the fallers were hospitalized and average of hospitalization was 22.3 days. 14) The six fallers(1.46%) died from fall injuries. The two fallers died from intracranial hemorrage and the four fallers died of secondary infection; pneumonia(2), sepsis(1) and cell lulitis(1). It is suggested that 1) Further study is needed with larger sample size to identify the fall risk factors. 2) After the fall accident, comprehensive nursing care and regular physical exercise should be emphasized for the elderly person. 3) Safety education and safety facilities of the public place and home is necessary for fall prevention.

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Monitoring of the Sea Surface Temperature in the Saemangeum Sea Area Using the Thermal Infrared Satellite Data (열적외선 위성자료를 이용한 새만금 해역 해수표면온도 모니터렁)

  • Yoon, Suk;Ryu, Joo-Hyung;Min, Jee-Eun;Ahn, Yu-Hwan;Lee, Seok;Won, Joong-Sun
    • Korean Journal of Remote Sensing
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    • v.25 no.4
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    • pp.339-357
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    • 2009
  • The Saemangeum Reclamation Project was launched as a national project in 1991 to reclaim a large coastal area of 401 km$^2$ by constructing a 33-km long dyke. The final dyke enclosure in April 2006 has transformed the tidal flat into lake and land. The dyke construction has abruptly changed not only the estuarine tidal system inside the dyke, but also the coastal marine environment outside the dyke. In this study, we investigated the spatial change of SST distribution using the Landsat-5/7 and NOAA data before and after the dyke completion in the Saemangeum area. Satellite-induced SST was verified by compared with the various in situ measurements such as tower, buoy, and water sample. The correlation coefficient resulted in above 0.96 and RMSE was about 1$^{\circ}C$ in all data. 38 Landsat satellite images from 1985 to 2007 were analyzed to estimate the temporal and spatial change of SST distribution from the beginning to the completion of the Samangeum dyke's construction. The seasonal change in detailed spatial distribution of SST was measured, however, the estimation of change during the Saemangeum dyke's construction was hard to figure out owing to the various environmental conditions. Monthly averaged SST induced from NOAA data from 1998 to 2007 has been analyzed for a complement of Landsat's temporal resolution. At the inside of the dyke, the change of SST from summer to winter was large due to the relatively high temperature in summer. In this study, multi-sensor thermal remote sensing is an efficient tool for monitoring the temporal and spatial distribution of SST in coastal area.

Monitoring on Physicochemical Properties of Liriope platyphylla by the Use of Four Dimensional Response Surface (4차원 반응표면분석을 통한 맥문동의 이화학적 특성 모니터링)

  • Lee, Gee-Dong;Kim, Jung-Ok;Son, Jun-Ho;Kim, Hak-Yoon
    • Food Science and Preservation
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    • v.19 no.4
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    • pp.560-568
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    • 2012
  • Four dimensional response surface methodology was used to monitor the extraction conditions and predict the optimum extraction conditions on physicochemical properties of Liriope platyphylla. Maximum yield of total soluble solid was 66.02% into range of 35.06~65.70%, and maximum extraction conditions were 16.86 mL/g in ratio of solvent to sample, $99.55^{\circ}C$ in extraction temperature and 3.20 hr in extraction time. Maximum extraction conditions of total phenolics were 18.78 mL/g, $97.09^{\circ}C$ and 3.71 hr. Maximum content of crude saponin was 6.51% into range of 2.22~6.21 %, and maximum extraction conditions were 21.33 mL/g, $95.49^{\circ}C$ and 3.00 hr. Maximum content of reducing sugar was 6.75% into range of 2.43~6.51%, and maximum extraction conditions were 22.93 mL/g, $89.64^{\circ}C$ and 3.75 hr. Electron donating ability was maximized in 16.74 mL/g, $99.63^{\circ}C$ and 3.16 hr. The range of optimum conditions gained by the superimposed four dimensional response surfaces on total soluble solid, crude saponin and reducing sugar of Liriope platyphylla was 15~23 mL/g, 92~$100^{\circ}C$ and 2.4~5.0 hr. And total soluble solid, total phenolics, crude saponin, reducing sugar, browning color intensity and electron donating ability at the given conditions(20 mL/g, $100^{\circ}C$, 3 hr) within the range of optimum conditions were 65.75%, 1.30 mg/g, 6.33%, 5.93%, 0.11 and 10.52%, respectively.