• Title/Summary/Keyword: PC index

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Estimation of Polar Cap Potential and the Role of PC Index

  • Moon, Ga-Hee
    • Journal of Astronomy and Space Sciences
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    • v.29 no.3
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    • pp.259-267
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    • 2012
  • Polar cap potential has long been considered as an indicator for the amount of energy flowing in the magnetosphere-ionosphere system. Thus, the estimation of polar cap potential is important to understand the physical process of the magnetosphere. To estimate the polar cap potential in the Northern Hemisphere, merging electric field by Kan & Lee (1979) is adopted. Relationships between the PC index and calculated merging electric field ($E^*$) are examined during full-time and storm-time periods separately. For this purpose Dst, AL, and PC indices and solar wind data are utilized during the period from 1996-2003. From this linear relationship, polar cap potential (${\Phi}^*$) is estimated using the formula by Doyle & Burke (1983). The values are represented as $58.1{\pm}26.9$ kV for the full-time period and $123.7{\pm}84.1$ kV for a storm-time period separately. Considering that the average value of polar cap potential of Doyle & Burke (1983) is about 47 kV during moderately quiet intervals with the S3-2 measurements, these results are similar to such. The monthly averaged variation of Dst, AL, and PC indices are then compared. The Dst and AL indices show distinct characteristics with peaks during equinoctial season whereas the average PC index according to the month shows higher values in autumn than in spring. The monthly variations of the linear correlation coefficients between solar wind parameters and geomagnetic indices are also examined. The PC-AL linear correlation coefficient is highest, being 0.82 with peaks during the equinoctial season. As with the AL index, the PC index may also prove useful for predicting the intensity of an auroral substorm. Generally, the linear correlation coefficients are shown low in summer due to conductance differences and other factors. To assess the role of the PC index during the recovery phase of a storm, the relation between the cumulative PC index and the duration is examined. Although the correlation coefficient lowers with the storm size, it is clear that the average correlation coefficient is high. There is a tendency that duration of the recovery phase is longer as the PC index increases.

Evaluation of Smoke Risk and Smoke Risk Rating for Combustible Substances from Fire (화재로부터 연소성 물질에 대한 연기위험성 및 연기위험성 등급 평가)

  • Chung, Yeong-Jin;Jin, Eui;You, Ji Sun
    • Applied Chemistry for Engineering
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    • v.32 no.2
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    • pp.197-204
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    • 2021
  • This study investigated the smoke risk assessment of woods and plastics for construction materials, focusing on the smoke performance index-V (SPI-V), smoke growth index-V (SGI-V), and smoke risk index-VI (SRI-VI) according to a newly designed methodology. Spruce, Lauan, polymethylmethacrylate (PMMA), and polycarbonate (PC) were used for test pieces. Smoke characteristics of the materials were measured using a cone calorimeter (ISO 5660-1) equipment. The smoke performance index-V calculated after the combustion reaction was found to be 1.0 to 3.4 based on PMMA. Smoke risk by smoke performance index-V was increased in the order of PC, Spruce, Lauan and PMMA. Lauan and PMMA showed similar values. The smoke growth index-V was found to be 1.0 to 9.2 based on PMMA. Smoke risk by smoke growth index-V increased in the order of PMMA, PC, Spruce, and Lauan. COpeak production rates of all specimens were measured between 0.0021 to 0.0067 g/s. In conclusion, materials with a low smoke performance index-V and a high smoke growth index-V cause a high smoke risk from fire. Therefore, it is understood that the smoke risk from fire is high. It is collectively summarized by the smoke risk index-VI.

Korean internet audience centric measurement : Internet index (PcMeter를 이용한 인터넷 접속을 측정)

  • 이상경
    • Survey Research
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    • v.1 no.1
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    • pp.125-134
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    • 2000
  • It is very important to keep scientific principles in marketing research, Especially in sampling we have to select the scheme to avoid self-selection bias Internet index is ready-made-research service produced by analyzing the log data transferred from PcMeter installed in panelists PC with panelists profile and site data base following the scientific principles Through the index we can figure out the actual behaviour of Korean netizen surfing various web sites and understand their cybergraphics.

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Investigating the Incidence of Prostate Cancer in Iran 2005-2008 using Bayesian Spatial Ecological Regression Models

  • Haddad-Khoshkar, Ahmad;Koshki, TohidJafari;Mahaki, Behzad
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.14
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    • pp.5917-5921
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    • 2015
  • Background: Prostate cancer is the most commonly diagnosed form of cancer and the sixth leading cause of cancer-related deaths among men in the entire world. Reported standardized incidence rates are 12.6, 61.7, 11.9 and 27.9 in Iran, developed countries, developing countries and the entire world, respectively. The present study investigated the relative risk of PC in Iran at the province level and also explored the impact of some factors by the use of Bayesian models. Materials and Methods: Our study population was all men with PC in Iran from 2005 to 2008. Considered risk factors were smoking, fruit and vegetable intake, physical activity, obesity and human development index. We used empirical and full Bayesian models to study the relative risk in Iran at province level to estimate the risk of PC more accurately. Results: In Iran from 2005 to 2008 the total number of known PC cases was 10,361 with most cases found in Fars and Tehran and the least in Ilam. In all models just human development index was found to be significantly related to PC risk Conclusions: In the unadjusted model, Fars, Semnam, Isfahan and Tehran provinces have the highest and Sistan-and-Baluchestan has the least risk of PC. In general, central provinces have high risk. After adjusting for covariates, Fars and Zanjan provinces have the highest relative risk and Kerman, Northern Khorasan, Kohgiluyeh Boyer Ahmad, Ghazvin and Kermanshah have the lowest relative risk. According to the results, the incidence of PC in provinces with higher human development index is higher.

Variations in Karyotypic Characteristics of Different Breed Groups of Water Buffaloes (Bubalus bubalis)

  • Bondoc, O.L.;Flor, M.C.G.T.;Rebollos, S.D.N.;Albarace, A.G.
    • Asian-Australasian Journal of Animal Sciences
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    • v.15 no.3
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    • pp.321-325
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    • 2002
  • Karyotype analysis was carried out on blood samples of 30 water buffaloes belonging to different breed groups (i.e. Philippine Carabao (PC), Indian Murrah (IM), Bulgarian Murrah (BM), "$F_1$ 50% IM-50% PC", "$F_1$ 50% BM-50% PC" and "75% IM-25% PC"), using the modified Leucocyte Culture Technique. The modal chromosome numbers of the PC, "$F_1$ 50% IM-50% PC", "$F_1$ 50% BM-50% PC", IM, BM and "75% IM-25% PC" were 2n=48, 49, 49, 50, 50 and 50, respectively. The water buffalo chromosomes are mostly acrocentric (79.67%) and the remainder submetacentric (20.33%). Results of the ordinary least square analysis showed significant breed effects (p<0.01) on other karyotypic characteristics (i.e. relative length, arm ratio and centromeric index). Significant correlation between karyotypic characteristics and some animal performance traits were also found. The significant correlation values imply that karyotypic characteristics can be used as important criteria to select potentially productive young water buffaloes. In the future, more production and reproduction traits from non-institutional herds should be included in the analysis to reveal meaningful correlations with various karyotypic characteristics.

Global Prostate Cancer Incidence and Mortality Rates According to the Human Development Index

  • Khazaei, Salman;Rezaeian, Shahab;Ayubi, Erfan;Gholamaliee, Behzad;Pishkuhi, Mahin Ahmadi;Khazaei, Somayeh;Mansori, Kamyar;Nematollahi, Shahrzad;Sani, Mohadeseh;Hanis, Shiva Mansouri
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.8
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    • pp.3793-3796
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    • 2016
  • Background: Prostate cancer (PC) is one of the leading causes of death, especially in developed countries. The human development index (HDI) and its dimensions seem correlated with incidence and mortality rates of PC. This study aimed to assess the association of the specific components of HDI (life expectancy at birth, education, gross national income per 1000 capita, health, and living standards) with burden indicators of PC worldwide. Materials and Methods: Information of the incidence and mortality rates of PC was obtained from the GLOBOCAN cancer project in year 2012 and data about the HDI 2013 were obtained from the World Bank database. The correlation between incidence, mortality rates, and the HDI parameters were assessed using STATA software. Results: A significant inequality of PC incidence rates was observed according to concentration indexes=0.25 with 95% CI (0.22, 0.34) and a negative mortality concentration index of -0.04 with 95% CI (-0.09, 0.01) was observed. Conclusions: A positive significant correlation was detected between the incidence rates of PC and the HDI and its dimensions including life expectancy at birth, education, income, urbanization level and obesity. However, there was a negative significant correlation between the standardized mortality rates and the life expectancy, income and HDI.

A Study on the Rheological Properties of Branched Polycarbonates by Melt Polymerization (용융중합에 의한 분지형 폴리카보네이트의 유변학적 특성 연구)

  • Choi, Su-Jung;Yoon, Kyung-Hwa;Kim, Hee-Seung;Yoo, Seung-Yoon;Kim, Youn-Cheol
    • Polymer(Korea)
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    • v.35 no.4
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    • pp.356-362
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    • 2011
  • The branched polycarbonates (B-PCs) with two different branching agents were synthesized from melt polymerization. The contents of branching agent were in the range of 0.001~0.005 mol%. The chemical structure of the synthesized PC was determined by FTIR, $^1H$ NMR, and $^{13}C$ NMR, spectroscopy. The molecular weight, glass transition and degradation temperatures were determined by GPC, DSC, and TGA. The molecular weight of the phloro type B-PC had a lower value than the other one, and the glass transition temperature increased with molecular weight. Compared with linear PC, the rheological properties of the B-PC indicated an increase of complex viscosity in the low frequency region and shear thinning tendency. Power law index(n) representing shear thinning was calculated by linear regression and the values were in the range of 0.483~0.996. The rheological properties of the B-PCs were measured by a dynamic rheometer.

Study on the Change of Physical Properties in Polyurethane Foam by NCO index at the Aging Condition (NCO index에 따른 폴리우레탄 폼의 노화 물성변화 연구)

  • Kim, Kwangin;Kim, Sangbum
    • Journal of the Korean Institute of Gas
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    • v.16 no.6
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    • pp.115-122
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    • 2012
  • Polyurethane foams were synthesized with different contents and kinds of catalysts to know change of properties under various NCO index. UTM(universal testing machine), DSC(differential scanning calorimetry), SEM(scanning electron microscope) and FT-IR(Fourier transform spectroscopy) were used for studying the PUF's physical properties change. Compressive strength of PUF increased with increasing contents of catalyst. Glass transition temperature(Tg) and compressive strength of PUF using PC-8 and 33LV catalyst, increased with increasing NCO index at the aging. According to the results of Infrared spectral analysis, reduction of NCO peak was found in gelling catalyst, because unreacted NCO reacted with polyurethane. Although Tg and compressive strength of PUF using TMR-2, unchanged with increasing NCO index at the aging, because trimerization of isocyanate.

Preparation of Hard Coating Solutions with High Refractive Index for Polycarbonate Sheet by the Sol-Gel Method (Sol-Gel 법에 의한 Polycarbonate 시트에 적용 가능한 고굴절률을 보이는 하드코팅 용액의 제조)

  • Cheong, Il Yeop;Cho, Kyung In;Cheong, Sang Hyuk;Park, Hyo Nam;Song, Ki Chang
    • Korean Chemical Engineering Research
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    • v.45 no.4
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    • pp.335-339
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    • 2007
  • In order to overcome the problem of poor hardness of transparent polycarbonate (PC) sheets, organic-inorganic hybrid hard coating solutions, which show a high refractive index above 1.58, were made by the sol-gel method. These hybrid coating solutions were obtained from mixture of titanium tetraisopropoxide (TTIP), and (3-glycidoxypropyl)trimethoxysilane (GPTMS). The PC sheets were spin-coated, and cured at $120^{\circ}C$ for 2 hr. Change of refractive index in the range of 1.53-1.61 was obtained by varying the GPTMS content. The refractive index of the coated film decreased with increasing the GPTMS content, while the pencil hardness of the coated film was found to increase with increasing the GPTMS content.

Term Clustering and Duplicate Distribution for Efficient Parallel Information Retrieval (효율적인 병렬정보검색을 위한 색인어 군집화 및 분산저장 기법)

  • 강재호;양재완;정성원;류광렬;권혁철;정상화
    • Journal of KIISE:Software and Applications
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    • v.30 no.1_2
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    • pp.129-139
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    • 2003
  • The PC cluster architecture is considered as a cost-effective alternative to the existing supercomputers for realizing a high-performance information retrieval (IR) system. To implement an efficient IR system on a PC cluster, it is essential to achieve maximum parallelism by having the data appropriately distributed to the local hard disks of the PCs in such a way that the disk I/O and the subsequent computation are distributed as evenly as possible to all the PCs. If the terms in the inverted index file can be classified to closely related clusters, the parallelism can be maximized by distributing them to the PCs in an interleaved manner. One of the goals of this research is the development of methods for automatically clustering the terms based on the likelihood of the terms' co-occurrence in the same query. Also, in this paper, we propose a method for duplicate distribution of inverted index records among the PCs to achieve fault-tolerance as well as dynamic load balancing. Experiments with a large corpus revealed the efficiency and effectiveness of our method.