• Title/Summary/Keyword: 동질이상

Search Result 140, Processing Time 0.025 seconds

Effects of Temperature and Saturation on the Crystal Morphology of Aragonite (CaCO3) and the Distribution Coefficient of Strontium: Study on the Properties of Strontium Incorporation into Aragonite with respect to the Crystal Growth Rate (온도와 포화도가 아라고나이트(CaCO3)의 결정형상과 스트론튬(Sr)의 분배계수에 미치는 영향: 결정성장속도에 따른 아라고나이트 내 스트론튬 병합 특성 고찰)

  • Lee, Seon Yong;Chang, Bongsu;Kang, Sue A;Seo, Jieun;Lee, Young Jae
    • Korean Journal of Mineralogy and Petrology
    • /
    • v.34 no.2
    • /
    • pp.133-146
    • /
    • 2021
  • Aragonite is one of common polymorphs of calcium carbonate (CaCO3) and formed via biological or physical processes through precipitation in many different environments including marine ecosystems. It is noted that aragonite formation and growth as well as the substitution of trace elements such as strontium (Sr) in the aragonite structure would be dependant on several key parameters such as concentrations of chemical species and temperature. In this study, properties of the incorporation of Sr into aragonite were investigated over a wide range of various saturation conditions and temperatures similar to the marine ecosystem. All pure aragonite samples were inorganically synthesized through a constant-addition method with varying concentrations of the reactive species ([Ca]=[CO3] 0.01-1 M), injection rates of the reaction solution (0.085-17 mL/min), and solution temperatures (5-40 ℃). Pure aragonite was also formed even under the Sr incorporation conditions (0.02-0.5 M, 15-40 ℃). When temperature and saturation index (SI) with respect to aragonite increased, the crystallinity and the crystal size of aragonite increased indicating the growth of aragonite crystal. However, it was difficult to interpret the crystal growth rate because the crystal growth rate calculated using BET-specific surface area was significantly influenced by the crystal morphology. The distribution coefficient of Sr (KSr) into aragonite decreased from 2.37 to 1.57 with increasing concentrations of species (Ca2+ and CO32-) at a range of 0.02-0.5 M. Similarly, it was also found that KSr decreased 1.90 to 1.54 at a range of 15-40 ℃. All KSr values are greater than 1, and the inverse correlation between the KSr and the crystal growth rate indicate that Sr incorporation into aragonite is in a compatible relationship.

The Comparative Study of NHPP Software Reliability Model Based on Exponential and Inverse Exponential Distribution (지수 및 역지수 분포를 이용한 NHPP 소프트웨어 무한고장 신뢰도 모형에 관한 비교연구)

  • Kim, Hee-Cheul;Shin, Hyun-Cheul
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
    • /
    • v.9 no.2
    • /
    • pp.133-140
    • /
    • 2016
  • Software reliability in the software development process is an important issue. Software process improvement helps in finishing with reliable software product. Infinite failure NHPP software reliability models presented in the literature exhibit either constant, monotonic increasing or monotonic decreasing failure occurrence rates per fault. In this paper, we were proposed the reliability model with the exponential and inverse exponential distribution, which made out efficiency application for software reliability. Algorithm to estimate the parameters used to maximum likelihood estimator and bisection method, model selection based on mean square error (MSE) and coefficient of determination($R^2$), for the sake of efficient model, were employed. Analysis of failure, using real data set for the sake of proposing the exponential and inverse exponential distribution, was employed. This analysis of failure data compared with the exponential and inverse exponential distribution property. In order to insurance for the reliability of data, Laplace trend test was employed. In this study, the inverse exponential distribution model is also efficient in terms of reliability because it (the coefficient of determination is 80% or more) in the field of the conventional model can be used as an alternative could be confirmed. From this paper, the software developers have to consider life distribution by prior knowledge of the software to identify failure modes which can be able to help.

Ecological Landscape Evaluation for the Planning of River Rehabilitation: The Upper Areas at the Mangyeong River in Jeollabukdo, Korea (하천복원계획을 위한 생태경관 평가: 전북 만경강 상류지역을 사례로)

  • Lee, Myung-Woo
    • Journal of the Korean Institute of Landscape Architecture
    • /
    • v.34 no.4 s.117
    • /
    • pp.69-83
    • /
    • 2006
  • Nature rehabilitation has become a major theme in river management in South Korea. An analysis and evaluation of the landscape is a crucial step to select the suitable tracts for developing or conserving land use in the process of landscape planning. The purpose of this paper is to establish a hierarchical procedure for the setting of the landscape units on the various scales at which field biologists performed their observations and to select the preserves through by a suitability model for synthesizing the ecological empirical, and biophysical data. An evaluation process needs to be performed according to the landscape scales: site, local, and regional scales, at which the environmental data were collected, analyzed, and synthesized. Introducing of three level scales was crucially necessary for evaluating the various multi level ecological data for zoning of preserves in river corridors. The evaluation level at different scales are hierarchically established into three phases. The first evaluation phase can be performed by the long length units defined by the ranges of stream widths at regional scale. Secondly, each of these long units can be divided into two or more segments according to its landscape homogeneity at local level. Finally the segments at the last phase can be designated according to the location of the reservoir weirs and bridges at site level. The conceptual model components are adopted for collecting, evaluating, and interpreting the biological and abiotic data at site level. Three preserves are selected, having high potentials for being intensely managed as the Ecological Education Areas in the river. Despite a lot of assumption the results are expected to facilitate discussion and decision making about which frameworks of evaluation are desirable and adaptable for integrating the ecological data into the rehabilitation design process in South Korea.

Characterization of Superoxide-dependent Endothelial Relaxing Factor(s) (Superoxide에 의존하여 내피세포에서 유리되는 이완성 물질의 특성에 대한 실험적 연구)

  • Lee, Gi-Nam;Lee, Won-Suk;Rhim, Byung-Yong;Hong, Ki-Whan
    • The Korean Journal of Pharmacology
    • /
    • v.26 no.2
    • /
    • pp.145-152
    • /
    • 1990
  • We recently reported a development of an experimental system which can identify the release of a superoxide-dependent vasorelaxant factor from endothelial cells using a two-bath system. In the present work, we further exploited the above system and observed whether the superoxide-dependent relaxing factor(s), released from the porcine coronary artery (PCA) endothelium, was similar in relaxation to those obtained from cat thoracic aortic endothelium and cultured endothelial cells of bovine aorta. However, there was observed a novel difference among the former one and the latter two relaxing factors; the release of relaxing factor from PCA endothelium can be inhibited either by catalase or by superoxide dismutase (SOD), whereas the latter two can be inhibited only by SOD. It was further attempted to characterize the synthetic mechanisms of the relaxing factors: (1) They were readily inhibited by various lipoxygenase inhibitors (gossypol, nordihydroguaiaretic acid, AA 861, and eicosatetraynoic acid). (2) They were not inhibited by cyclooxygenase inhibitor (indomethacin) and by cytochrome P-450 monooxygenease inhibitors (proadifen and cimetidine). Thus, it is likely that these relaxing factors, although obtained from different species, show common functional roles of arteriolar relaxation. It is suggested that they are related to pathophysiological involvement of various tissue ischemia-reperfusion injuries.

  • PDF

A Meta-Analysis for the Effect of Forest Experience on Young Children: Effect Size on the Moderating Variables (유아 숲 체험활동의 효과에 대한 메타분석: 중재변인별 효과크기를 중심으로)

  • Cho, Young-Min;Kim, Dong-Jun;Yeoun, Poung-Sik;Lee, Kyu-Ha;Lee, Hyo-Eun;Park, Kuen-Tae;Lee, Eun-Jeong;Lee, Bo-Bae
    • Journal of Korean Society of Forest Science
    • /
    • v.105 no.1
    • /
    • pp.139-148
    • /
    • 2016
  • The purpose of this study was to evaluate critically the effects of forest experience on young children using meta-analysis. To test this, a total 30 studies were identified, and mean effect size of variables was calculated by applying Fixed-effect model. As a result, the overall effect size of forest experience on young children was 0.797. The effect sizes of daily type as a program type had an effect than experience type at the level of .939. And also the effect sizes of period program (more 4month), number of participants (10-20people), program time (180minute), dependant variables (multiple intelligence) yield effects 0.972, 0.980, 1.138 and 0.957 respectively. As the result, this study implies a way which is to derive effectively further studies on the forest experience on young children.

A Comparative Study on the Infinite NHPP Software Reliability Model Following Chi-Square Distribution with Lifetime Distribution Dependent on Degrees of Freedom (수명분포가 자유도에 의존한 카이제곱분포를 따르는 무한고장 NHPP 소프트웨어 신뢰성 모형에 관한 비교연구)

  • Kim, Hee-Cheul;Kim, Jae-Wook
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
    • /
    • v.10 no.5
    • /
    • pp.372-379
    • /
    • 2017
  • Software reliability factor during the software development process is elementary. Case of the infinite failure NHPP for identifying software failure, the occurrence rates per fault (hazard function) have the characteristic point that is constant, increases and decreases. In this paper, we propose a reliability model using the chi - square distribution which depends on the degree of freedom that represents the application efficiency of software reliability. Algorithm to estimate the parameters used to the maximum likelihood estimator and bisection method, a model selection based on the mean square error (MSE) and coefficient of determination($R^2$), for the sake of the efficient model, were employed. For the reliability model using the proposed degree of freedom of the chi - square distribution, the failure analysis using the actual failure interval data was applied. Fault data analysis is compared with the intensity function using the degree of freedom of the chi - square distribution. For the insurance about the reliability of a data, the Laplace trend test was employed. In this study, the chi-square distribution model depends on the degree of freedom, is also efficient about reliability because have the coefficient of determination is 90% or more, in the ground of the basic model, can used as a applied model. From this paper, the software development designer must be applied life distribution by the applied basic knowledge of the software to confirm failure modes which may be applied.

Effects of the Aroma Inhalation Method with a Roll-on on Life Stress, Salivary Cortisol and Fatigue in Nursing Student (아로마 롤온흡입법이 간호대학생의 생활 스트레스, 타액 코티졸 및 피로에 미치는 효과)

  • Kim, In-Sook;Kang, Seung-Ju;Kim, Ja-Ok
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.15 no.12
    • /
    • pp.7214-7223
    • /
    • 2014
  • Purpose: This study examined the effects of aroma inhalation method with roll-on on life stress, salivary cortisol and fatigue in nursing student preparing national examination for nursing licensure. Methods: The study was a nonequivalent control group pre-post test design. The participants were 46 nursing students of which 21 were assigned to the experimental group and 25 to the control group. Data was collected from October 10 to November 21, 2011 and analyzed using the SPSS Win 18.0 version program. The intervention was conducted 3 times a day for 6 weeks. Results: Significant differences in reported life stress experience frequency and fatigue between the two groups. On the other hand, the issue of salivary cortisol and life stress importance rate was not significant. Conclusion: Aroma inhalation method with roll-on can be used as an effective intervention to decrease life stress experience frequency and fatigue of nursing students with national examination for nursing licensure.

A Study on the Quantitative Analysis for the Forest Landscape (삼림경관에 관한 계량적 분석에 관한 연구)

  • 서주환
    • Journal of the Korean Institute of Landscape Architecture
    • /
    • v.15 no.1
    • /
    • pp.39-67
    • /
    • 1987
  • The purpose of this thesis is to suggest objective basic data for the environmental design through the quantitative analysis of the visual quality included in the physical environment of forest landscape. For this, landscape values of forest landscape have been evaluated by using the Iverson method, the images structure of forest landscape's main utilizing space have been analysed by the factor analysis algorithm, degree of visual preferences have been pleasured mainly by questionnaries and SBE method, and finally these thesis can be summarized as fallow LCP with high values of Iverson factors I and IV yield high landscape value. Specifically, Iverson factor IV has been found to play the dominant. For all experimental points, significant seasonal variations in S.D. scale values have been observed. In natural parks, where artificial structures are complementary to the natural landscape, main factors of image are S.D. scales such as the visual sequence, the formal simplicity of structures, the emphasis, the unification of heterogeneous factors and the assimilation. Factors covering the spatial image of natural parks have been found to be the overall evaluation, the individual characteristics, the tidiness, the potentiality, the dignity, the intimacy and the space volume. For all seasons, factors such as the individual characteristics, the dignity, the tidiness, the potentiality, yield high factor scores. As for factors determining the degree of visual preference, variables such as the summit, the skyline, rocks, the water and the degree of natural destruction by artificial structures yield high values for all seasons.

  • PDF

A Study on Homogeneity Analysis of the Guipi Decoction for Treatment of Insomnia Disorder -Focusing on Randomized Controlled Clinical Trials in CNKI (불면장애에 사용된 귀비탕의 동질성 연구 -CNKI에서 검색한 무작위배정 임상연구를 중심으로-)

  • Kim, Dong-Hee;Sakong, Jong-Won;Kang, Chang-Wan;Lee, Sang-Hyup;Ha, Ji-Won;Kim, Bo-Kyung
    • Journal of Oriental Neuropsychiatry
    • /
    • v.29 no.3
    • /
    • pp.145-163
    • /
    • 2018
  • Objectives: The study was designed to provide clinical evidence of homogeneity in analysis of the herbal medicine, Guipi decoction in treating insomnia, using a t-test of randomized controlled trials (RCTs). Methods: This study included RCTs that verified homogeneity of Guipi decoction in treating insomnia. Literature studies of CNKI (Chinese National Knowledge Infrastructure Database) were performed. The basic components group was made to the Guipi decoction of the Yixuerumen?s text. The excluded group was created with the number of herbs excluded from the basic components group. T-test performed that the effective rate in the basic components group and excluded groups. Results: The basic components of Guipi decoction contain Atractylodis Rhizoma Alba, Poria Sclerotium (Poria Sclerotium Cum Pini Radix), Polygalae Radix, Astragali Radix, Zizyphi Semen, Angelicae Gigantis Radix, Aucklandiae Radix, Glycyrrhiza uralensis Fischer, Ginseng Radix (Codonopsis Pilosulae Radix), Longanae Arillus. Herbs excluded from the basic components group were Longanae Arillus, Ginseng Radix (Codonopsis Pilosulae Radix), Glycyrrhiza uralensis Fischer and herbs added to the basic components group were Polygonum multiflorum Thunberg, Schisandrae Fructus, Salviae Militiorrhizae Radix, Paeoniae Radix Alba (in order from the most used to the least). T-test revealed the effective rate in the basic components group was not statistically significant compared to the excluded groups (p=0.161/p=0.162/p=0.103). Conclusions: Effectiveness in treatment of basic components of Guipi decoction and excluded groups were revealed to be homogeneous in treating insomnia. As the number of herbs in the basic components group decreased, mean value in effectiveness of treatment also decreased consequentially. However, there were no statistical significances.

Effects of Integrated Palliative Care Intervention on Quality of Life in Terminal Cancer Patients: A Meta-analysis (통합적 완화 돌봄 중재가 말기암환자의 삶의 질에 미치는 효과: 메타분석)

  • Jo, Kae Hwa;Park, Ae Ran;Lee, Jin Ju
    • Journal of Hospice and Palliative Care
    • /
    • v.18 no.2
    • /
    • pp.136-147
    • /
    • 2015
  • Purpose: This study was conducted to evaluate the effects of integrated palliative care intervention on quality of life in terminally ill patients. Methods: A comprehensive literature search was performed via PubMed, Cochrane Library CENTRAL, LWW (Ovid), CINAHL and several Korean databases. The main search strategy was to combine terms indicating palliative care intervention, presence of terminal illness and study design. Methodological quality was assessed using Cochrane's Risk of Bias for randomized studies and Risk of Bias Assessment tool for non-randomized studies. Data were analyzed by the Stata 10 program. Results: Eight clinical trials met the inclusion criteria with a total of 356 participants. Integrated palliative care interventions were administered for a mean of 6.5 weeks, 5.6 sessions and an average of 47.8 minutes per session. Effect sizes were heterogeneous, and subgroup analysis was done. Integrated palliative care interventions had a significant effect on quality of life (ES=1.83, P=0.018, $l^2=92%$), spiritual well-being (ES=0.78, P=0.040, $l^2=0$), depression (ES=0.86, P<0.001, $l^2=32$) and anxiety (ES=0.69, P=0.041, $l^2=71.1$). But integrated palliative care interventions had no significant effect on pain (ES=0.365, P=0.230, $l^2=69.8$). Conclusion: Results support findings that integrated palliative care interventions were helpful in lessening depression and anxiety and improving quality of life and spiritual well-being, however, the interventions did not assist pain management in terminal cancer patients. These findings suggest that various integrated palliative care interventions can assist terminal cancer patients with better quality of life in the socio-psycho-spiritual dimension.