• Title/Summary/Keyword: density index

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Quantification of Plant Safety Status

  • Cho, Joo-Hyun;Lee, Gi-Won;Kwon, Jong-Soo;Park, Seong-Hoon;Na, Young-Whan
    • Nuclear Engineering and Technology
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    • v.28 no.5
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    • pp.431-439
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    • 1996
  • In the process of simplifying the complex fate of the plant into a binary state, the information loss is inevitable. To minimize the information loss, the quantification of plant safety status has been formulated through the combination of the probability density function arising from the sensor measurement and the membership function representing the expectation of the state of the system. Therefore, in this context, the safety index is introduced in an attempt to quantify the plant status from the perspective of safety. The combination of probability density function and membership function is achieved through the integration of the fuzzy intersection of the two functions, and it often is not a simple task to integrate the fuzzy intersection due to the complexity that is the result of the fuzzy intersection. Therefore, a methodology based on the Algebra of Logic is used to express the fuzzy intersection and the fuzzy union of the arbitrary functions analytically. These exact analytical expressions are then numerically integrated by the application of Monte Carlo method. The benchmark tests for rectangular area and both fuzzy intersection and union of two normal distribution functions have been performed. Lastly, the safety index was determined for the Core Reactivity Control of Yonggwang 3&4 using the presented methodology.

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Study on Halogen Free Low Smoke Polyolefin (할로겐이 없는 저연성 폴리올레핀에 관한 연구)

  • Kim, Young-Doo;Chung, Kwang-Soo;Kim, Tae-Ho
    • Elastomers and Composites
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    • v.37 no.3
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    • pp.177-182
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    • 2002
  • For low-smoke-type polyolefin compound, LDPE, EVA, and EEA as base resin, magnesium trihydrate, alumina trihydrate, and red phosphorous as flame retardant and MAH type compatibilizer were applied. The amount of each component was changed to find out optimum composition. Mechanical properties were obtained by tensile test and residual stress after aging and flame retardancy was evaluated by smoke density, LOI(Limit Oxygen Index), and UL-94 test. SEM was used for the investigation or morphology and halogen contents were obtained by measuring the amount of HCI. Two kinds of halogen free compositions for flame retardant and low smote resin were found and it is expected to be applied for various purposes.

Analysis of Functional Habitat Groups of Benthic Macroinvertebrates according to Changes in the Riverbed (하상 변화에 따른 저서성 대형무척추동물의 서식기능군 분석)

  • Lee, Seul Hee;Lee, Mi Jin;Seo, Eul Won;Lee, Jong Eun
    • Journal of Environmental Science International
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    • v.26 no.3
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    • pp.373-380
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    • 2017
  • This study identified the effect of changes in the riverbed on the benthic macroinvertebrate communities. The benthic macroinvertebrates collected from the surveyed sites belonged to 119 species, 65 families, 20 orders, and 7 classes in 4 phyla. The number of Ephemeroptera, Plecoptera, and Trichoptera (E.P.T) species was 42, 10, and 8, respectively, in the tributary, confluence, and Nakdong River sites. Lotic species (Hydropsychidae) showed a high density at the tributary sites, whereas lentic species (Chironomidae) showed a high density at the confluence and Nakdong River sites. Community analysis showed that the Dominance Index (DI) was 0.54 in tributary sites, and dominance indices increased closer to the Nakdong River sites. The diversity index (H') was inversely proportional to DI. The ratio of Burrowers species (BU) at the surveyed sites increased closer to the Nakdong River sites. Analysis of common species showed 37 species (34.6%) between the tributary and confluence sites and 66 species (51.5%) between the confluence and Nakdong River sites.

Species richness related to landscape characteristics of uninhabited islands in Korea

  • Rho, Paikho
    • Journal of Ecology and Environment
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    • v.33 no.2
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    • pp.105-114
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    • 2010
  • The principal objective of this study was to characterize the relationships between geographical conditions (e.g., island area, distance to mainland) and landscape structures of uninhabited islands, and to evaluate the effects of islands and their landscape structures on species richness. One hundred randomly selected islands and 5,000 m buffered areas derived from the boundaries of each island were used to summarize the number of observed bird species, and landscape pattern indices, particularly patch density, edge density, shape index, and mean nearest neighboring distance. Spatial arrangements of individual patch type at the class level, which are markedly affected by the distance from an island to the mainland, have a superior ability to explain the variances in species richness, as compared to the geographical conditions and landscape pattern indices at the landscape level. The results demonstrate that the patch type landscape structure is the primary factor affecting species richness, as well as the distance to the mainland. In particular, landscape pattern indices of cropland/pasture and woody cover are statistically significant in terms of explaining species richness, which suggests that food resources and appropriate conditions in landscape structures of habitat types are assumed as important elements in attracting bird species. This study also proposes the importance of evaluation on the landscape structure of each island, in order to designate protected areas and to establish a management plan for species conservation in uninhabited islands.

Effects of Extrusion Conditions on the Physicochemical Properties of Extruded Red Ginseng

  • Gui, Ying;Gil, Sun-Kuk;Ryu, Gi-Hyung
    • Preventive Nutrition and Food Science
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    • v.17 no.3
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    • pp.203-209
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    • 2012
  • The effects of variable moisture content, screw speed and barrel temperature on the physicochemical properties of red ginseng powder extrudates were investigated. The raw red ginseng powders were processed in a co-rotating intermeshing twin-screw extruder. Primary extrusion variables were feed moisture content (20 and 30%), screw speed (200 and 250 rpm) and barrel temperature (115 and $130^{\circ}C$). Extruded red ginseng showed higher crude saponin contents (6.72~7.18%) than raw red ginseng (5.50%). Tested extrusion conditions did not significantly affect the crude saponin content of extrudates. Increased feed moisture content resulted in increased bulk density, specific length, water absorption index (WAI), breaking strength, elastic modulus and crude protein content and decreased water solubility index (WSI) and expansion (p<0.05). Increased barrel temperature resulted in increased total sugar content, but decreased reducing sugar content in the extrudate (p<0.05). Furthermore, increased barrel temperature resulted in increased amino acid content and specific length and decreased expansion and bulk density of extrudates only at a higher feed moisture content. The physicochemical properties of extrudates were mainly dependent on the feed moisture content and barrel temperature, whereas the screw speed showed a lesser effect. These results will be used to help define optimized process conditions for controlling and predicting qualities and characteristics of extruded red ginseng.

The Effects of a Combined Exercise Program on Obesity and Metabolic Syndrome Factors for Chronic Psychiatric Inpatients (복합운동 프로그램이 만성정신질환자의 비만 및 대사 증후군 인자에 미치는 효과)

  • Son, Mi Ae;Lee, Yong Mi;Jung, Kye A
    • Journal of Korean Biological Nursing Science
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    • v.16 no.2
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    • pp.105-112
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    • 2014
  • Purpose: The purpose of this study was to examine the effects of a Combined Exercise Program on Obesity and Metabolic Syndrome Factors for Chronic Psychiatric Inpatients. Methods: Thirty two subjects participated in this program who were admitted into a national mental hospital of C city. All measurements were done at baseline, 4 week, 8 week, and 12 week during the program. The effectiveness of the program was evaluated according to the change of body mass index, body fat, waist circumference, total cholesterol, high density lipoprotein cholesterol, triglyceride, and fasting blood sugar. Collected data was analyzed by frequency, percentage, and repeated measures ANOVA with SPSS WIN 19.0. Results: There were statistically significant differences in the body mass index (p=.002), body fat (p<.001), waist circumference (p<.001), triglyceride (p=.020), and fasting blood sugar (p=.008). However, there were no statistically significant differences in the total cholesterol, or high density lipoprotein cholesterol. Conclusion: The results of this study showed that a combined exercise program has positive effect on obesity and metabolic syndrome factor. Thus, a Combined Exercise program is recommended as an intervention to improve obesity and metabolic syndrome factors for chronic psychiatric inpatients.

Influencing Factors on Cardio-cerebrovascular Disease Risk Factors in Young Men: Focusing on Obesity Indices (청년층 성인남성에서 흡연, 음주, 비만지표가 심뇌혈관계 위험인자에 미치는 영향)

  • Kim, Chul-Gyu;Lee, Shi Hyang;Cha, Sun Kyung
    • Journal of Korean Biological Nursing Science
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    • v.19 no.1
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    • pp.1-10
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    • 2017
  • Purpose: The purpose of this study was to investigate influences of drinking, smoking, and obesity indices on cardio-cerebrovascular disease risk factors in Korean young men. Methods: The subjects were 234 young men, aged 20 to 39 years. Body mass index (BMI), percent body fat (PBF), body fat mass (kg), and waist hip ratio (WHR) were measured as obesity indices. Systolic blood pressure (SBP), diastolic blood pressure (DBP), fasting blood sugar (FBS), total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) were measured as cardio-cerebrovascular disease risk factors. The data were analyzed by t-test, ANOVA, Pearson's correlation coefficient, and multiple regression analysis using SAS 9.4. Results: Statistically significant factors were BMI for SEP; age, degree of drinking, body fat mass for DBP; WHR for TC; WHR and age for TG; age, degree of smoking and PBF for HDL-C; WHR, age and degree of smoking for LDL-C. Conclusion: Factors identified in this study need to be considered in cardio-cerebrovascular disease prevention programs for young men.

Fluorescent White OLEDs with a High Color-rendering Index Using a Silicon-Cored Anthracene Derivative as a Blue Host

  • Kwak, Jeong-Hun;Lyu, Yi-Yeol;Lee, Hyun-Koo;Char, Kook-Heon;Lee, Chang-Hee
    • Journal of Information Display
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    • v.11 no.3
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    • pp.123-127
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    • 2010
  • Fluorescent white organic light-emitting diodes showing high color-rendering indices (CRIs) of up to 81 was demonstrated, with a silicon-cored anthracene derivative (PATSPA) doped with DPAVBi utilized as the deep-blue host and dye materials, and the commercial dyes rubrene and DCM2 utilized as the orange- and red-light-emitting dyes. The devices, consisting of three emissive layers, showed bright-white-light emission, but the ratio of the blue peak to the orange and red peaks changed with the current density and the thickness of the blue emissive layer. A high CRI was achieved with the use of a deep-blue emitter doped in a novel host and by optimizing the blue-layer thickness. The device with a blue-layer thickness of 10 nm showed the Commission Internationale de l'Eclairage (CIE) color coordinate of (0.33, 0.35), a high CRI of 81, and a moderate external quantum efficiency of 2% at a current density of $2.5\;mA/cm^2$.

Effect of Combined Exercise Program on Body Composition, Health-Related Fitness and Blood Lipid in Middle-Aged Man (중년남성의 복합운동프로그램에 따른 신체구성, 건강관련체력 및 혈중지질에 미치는 영향)

  • Seo Jeong-Hun
    • The Journal of the Korea Contents Association
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    • v.5 no.2
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    • pp.177-185
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    • 2005
  • The purpose of this study was to evaluate the effect of combined exercise on body composition, health-related fitness and blood lipid. Subjects was ten middle-aged man. The combined exercise program consisted of performed for 60min in a bout, 4 times a week at the intensity of heart rate max$(50\sim75%)$ for 12 weeks. and the change of %fat, learn body mass, body mass index, back strength, sit-up, sit and reach total cholesterol, low density lipoprotein cholesterol, triglyceride and high density lipoprotein cholesterol have been measured before and post exercise 12 weeks. Paired t-test was performed for data analysis at the 0.05 level of significance.

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Effects of low-head dam removal on benthic macroinvertebrate communities in a Korean stream

  • Kil, Hye-Kyung;Bae, Yeon-Jae
    • Animal cells and systems
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    • v.16 no.1
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    • pp.69-76
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    • 2012
  • This study was conducted to examine how a low-head dam removal (partial removal) could affect benthic macroinvertebrate communities in a stream. Benthic macroinvertebrates and substrates were seasonally sampled before and after dam removal (March 2006-April 2007). Benthic macroinvertebrates and substrates were quantitatively sampled from immediately upstream (upper: pool) and downstream (lower: riffle) sites, the location of the dam itself (middle), and immediately above the impoundment (control: riffle). After the removal, species richness and density of benthic macroinvertebrates as well as the EPT group (Ephemeroptera, Plecoptera and Trichoptera) increased to higher levels than those before the removal, while functional feeding groups and habitat orientation groups changed more heterogeneously at the upper site. At the lower site, species richness and density decreased somewhat immediately after dam removal, which was associated with an increase of silt and sand, but recovered after monsoon floods which helped to enhance substrate diversity at the upper site. Decreased dominance index and increased diversity index in both the upper and lower sites are evidence of positive effects from the dam removal. In conclusion, we suggest that even a partial removal of a dam, resulting in increased substrate diversity in the upper site, could sufficiently help rehabilitate lost ecological integrity of streams without major habitat changes.