• Title/Summary/Keyword: Frequency Index

Search Result 2,451, Processing Time 0.034 seconds

Spatial Patterns and Temporal Variability of the Haines Index related to the Wildland Fire Growth Potential over the Korean Peninsula (한반도 산불 확장 잠재도와 관련된 Haines Index의 시.공간적 특징)

  • Choi Cwang-Yong;Kim Jun-Su;Won Myoung-Soo
    • Journal of the Korean Geographical Society
    • /
    • v.41 no.2 s.113
    • /
    • pp.168-187
    • /
    • 2006
  • Windy meteorological conditions and dried fire fuels due to higher atmospheric instability and dryness in the lower troposphere can exacerbate fire controls and result in more losses of forest resources and residential properties due to enhanced large wildland fires. Long-term (1979-2005) climatology of the Haines Index reconstructed in this study reveals that spatial patterns and intra-annual variability of the atmospheric instability and dryness in the lower troposphere affect the frequency of wildland fire incidences over the Korean Peninsula. Exponential regression models verify that daily high Haines Index and its monthly frequency has statistically significant correlations with the frequency of the wildland fire occurrences during the fire season (December-April) in South Korea. According to the climatic maps of the Haines Index created by the Geographic Information System (GIS) using the Digital Elevation Model (DEM), the lowlands below 500m from the mean sea level in the northwestern regions of the Korean Peninsula demonstrates the high frequency of the Haines Index equal to or greater than five in April and May. The annual frequency of the high Haines Index represents an increasing trend across the Korean Peninsula since the mid-1990s, particularly in Gyeongsangbuk-do and along the eastern coastal areas. The composite of synoptic weather maps at 500hPa for extreme events, in which the high Haines Index lasted for several days consecutively, illustrates that the cold low pressure system developed around the Sea of Okhotsk in the extreme event period enhances the pressure gradient and westerly wind speed over the Korean Peninsula. These results demonstrate the need for further consideration of the spatial-temporal characteristics of vertical atmospheric components, such as atmospheric instability and dryness, in the current Korean fire prediction system.

Body mass Index and Food Habits of Female University Students in Seoul (서울 지역 여대생 체격지수와 식습관 -식품영양전공대학생을 중심으로-)

  • 정남용;최순남
    • Korean journal of food and cookery science
    • /
    • v.18 no.5
    • /
    • pp.505-515
    • /
    • 2002
  • The purpose of this study was to investigate the body mass index and food habits of female university students (nutrition majors) in Seoul. The means of height, weight and BMI were 161.22${\pm}$4.63cm, 52.76${\pm}$6.59kg, and 22.20${\pm}$3.98, respectively. Subjects were divided into 3 groups based on BMI. The ratio of underweight, normal, and overweight students was 25.2%, 56.3%, and 18.5%. respectively. There were significant differences in the recognition rate of body shape and the way to maintain health by BMI. And self satisfaction rate of body shape was significantly higher in underweight subjects compared with others. There was no significant difference in the rate of activity and exercise, food behavior, intake frequency of various foods, intake of convenience food and carbonated drink according to BMI. Weight and body fat of subjects had a significant correlation with BMI. and height, frequency of taking food, frequency of meals, food behavior, intake food, health and exercise consciousness rate showed no correlation with BMI.

Characteristics of Sound Reduction Index through Small Sized Lightweight Panel (소형 경량판넬을 이용한 차음성능 영향요인별 음향감쇠계수 분석)

  • Yang, Hong-Seok;Kim, Myung-Jun;Jeong, Gab-Chul
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 2007.11a
    • /
    • pp.138-147
    • /
    • 2007
  • Recently, framed structure is increasingly being used as apartment structure due to the advantages during remodeling. Therefore, the use of lightweight panel as separating wall is increasing. To construct lightweight panel structures with sound insulation performance appropriate to the conditions of each field, measurement of sound reduction index(SRI) through panel structures should be performed. In this study, measurement of SRI through 46 kinds of panel structures was performed in the condition of various factors such as surface density, air space and absorber. The result showed that SRI of panel structures was generally higher by increasing of surface density. In the case of double panel with no absorber, SRI at below critical frequency was gradually increased according to rise of air space. Double panel with absorber make remarkable improvement in SRI at low frequency, but there is a little difference compared with SRI of double panel with no absorber over critical frequency.

  • PDF

The Electrical and Optical Characteristics of Silica Sand by Terahertz Electromagnetic Pulses (테라헤르츠 전자기 펄스를 이용한 이산화규소의 전기적 광학적 특성)

  • 전태인
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.14 no.3
    • /
    • pp.202-206
    • /
    • 2001
  • Using THz time-domain spectroscopy (THz-TDS), the power absorption, the index of refraction, and the real conductivity of silica sand are measured from 0.1[Thz] to 0.5[Thz] frequency range. It is impossible to measure the characterization of the silica sand by simple electrical measurements using mechanical contacts, e.g., Hall effect or four-point probe measurements. However, the THz-TDS technique can measure not only electrical but also optical characterization of he sample. Also this technique can measure frequency dependent results. Especially, the real conductivity was increased according to THz frequency. This is unusual material compare with metal and semiconductor materials; the measured real conductivity are not followed by the simple Drude theory.

  • PDF

Development and Evaluation of Validity of Dish Frequency Questionnaire (DFQ) and Short DFQ Using Na Index for Estimation of Habitual Sodium Intake (나트륨 섭취량 추정을 위한 음식섭취빈도조사지와 Na Index를 이용한 간이음식섭취빈도조사지의 개발 및 타당성 검증에 관한 연구)

  • Son, Sook-Mee;Huh, Gwui-Yeop;Lee, Hong-Sup
    • Korean Journal of Community Nutrition
    • /
    • v.10 no.5
    • /
    • pp.677-692
    • /
    • 2005
  • The assessment of sodium intake is complex because of the variety and nature of dietary sodium. This study intended to develop a dish frequency questionnaire (DFQ) for estimating the habitual sodium intake and a short DFQ for screening subjects with high or low sodium intake. For DFQ112, one hundred and twelve dish items were selected based on the information of sodium content of the one serving size and consumption frequency. Frequency of consumption was determined through nine categories ranging from more than 3 times a day to almost never to indicate how often the specified amount of each food item was consumed during the past 6 months. One hundred seventy one adults (male: 78, female: 93) who visited hypertension or health examination clinic participated in the validation study. DFQ55 was developed from DFQ112 by omitting the food items not frequently consumed, selecting the dish items that showed higher sodium content per one portion size and higher consumption frequency. To develop a short DFQs for classifying subjects with low or high sodium intakes, the weighed score according to the sodium content of one protion size was given to each dish item of DFQ25 or DFQ14 and multiplied with the consumption frequency score. A sum index of all the dish items was formed and called sodium index (Na index). For validation study the DFQ112, 2-day diet record and one 24-hour urine collection were analyzed to estimate sodium intakes. The sodium intakes estimated with DFQ112 and 24-h urine analysis showed $65\%$ agreement to be classified into the same quartile and showed significant correlation (r=0.563 p<0.05). However, the actual amount of sodium intake estimated with DFQ112 (male: 6221.9mg, female: 6127.6mg) showed substantial difference with that of 24-h urine analysis (male: 4556.9mg, female: 5107.4mg). The sodium intake estimated with DFQ55 (male: 4848.5mg, female: 4884.3mg) showed small difference from that estimated with 24-h urine analysis, higher proportion to be classfied into the same quartile and higher correlation with the sodium intakes estimated with 24-h urine analysis and systolic blood pressure. It seems DFQ55 can be used as a tool for quantitative estimation of sodium intake. Na index25 or Na index14 showed $39\~50\%$ agreement to be classified into the same quartile, substantial correlations with the sodium intake estimated with DFQ55 and significant correlations with the sodium intake estimated with 24-h urine analysis. When point 119 for Na index25 was used as a criterion of low sodium intake, sensitivity, specificity and positive predictive value was $62.5\%,\;81.8\%\;and\;53.2\%$, respectively. When point 102 for Na index14 was used as a criterion of high sodium intake, sensitivity, specificity and positive predictive value were $73.8\%,\;84.0\%,\;62.0\%$, respectively. It seems the short DFQs using Na index 14 or Na index25 are simple, easy and proper instruments to classify the low or high sodium intake group.

A Analysis on Serum Total Cholesterol, Atherogenic Index of Medical Check-up Subjects in One University Hospital by Age and Sex (종합 건강검진자에서의 성별.연령별 혈청 총콜레스테롤, 동맥경화지수의 상호연관성 분석)

  • Suk, Sung-Ja;Yoo, Wang-Keun
    • Journal of Society of Preventive Korean Medicine
    • /
    • v.10 no.1
    • /
    • pp.67-74
    • /
    • 2006
  • Objectives: This study was carried out to establish the normal values of Serum Total Cholesterol, HDL-cholesterol by age and sex for healthy adult and the frequency of dyslipidemia as a risk factor of coronary atherosclerosis. Methods: Total cholesterol, and HDL-cholesterol measured among 14,485 in general growing people (8,712 males and 5,773 females) aged 20 to 69 years and analyzed to use the auto-analyzer Hitach 7600 in enzyme method. Result: 1. The levels of total cholesterol, HDL-cholesterol and atherogenic index were slightly positively correlated with age in both sexes. The mean values of serum lipid profiles were $190{\pm}32.9mg/dl$ in men and $181{\pm}32.8mg/dl$ in women for cholesterol, $50.1{\pm}11.4mg/dl$ in men and $54.5{\pm}12.0mg/dl$ in women for HDL-cholesterol, $3.9{\pm}1.0$ in men and $3.4{\pm}0.8$ in women for atherogenic index. 2. Mean values of total cholesterol and atherogenic index higher in men than in women at the age 20-40 years but significantly higher in women than in men at the age group 60 years.(p<0.001) 3. The frequency of hypercholesterolemia(${\geq}200mg/dl$) and low HDL-cholesterol(<35mg/dl) were increased with age in both sexs, significantly higher in women at the age group 60 years. The frequency of hypercholesterolemia(${\geq}200mg/dl$) and low HDL-cholesterol(<35mg/dl) in men and women was 37.5%, 25.3%, and 5.5%, 2.8%. Their requencies were higher in men than in women. Conclusion: Theses findings suggest that the mean concentrations of total cholesterol and HDL-cholesterol in men and women vary with age. The frequency of hypercholesterolemia(${\geq}200mg/dl$) in men and women was about 31.4% and increased with age.

  • PDF

Correlates of Digit Bias in Self-reporting of Cigarette per Day (CPD) Frequency: Results from Global Adult Tobacco Survey (GATS), India and its Implications

  • Jena, Pratap Kumar;Kishore, Jugal;Jahnavi, G.
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.14 no.6
    • /
    • pp.3865-3869
    • /
    • 2013
  • Background: Cigarette per day (CPD) use is a key smoking behaviour indicator. It reflects smoking intensity which is directly proportional to the occurrence of tobacco induced cancers. Self reported CPD assessment in surveys may suffer from digit bias and under reporting. Estimates from such surveys could influence the policy decision for tobacco control efforts. In this context, this study aimed at identifying underlying factors of digit bias and its implications for Global Adult Tobacco Surveillance. Materials or Methods: Daily manufactured cigarette users CPD frequencies from Global Adult Tobacco Survey (GATS) - India data were analyzed. Adapted Whipple Index was estimated to assess digit bias and data quality of reported CPD frequency. Digit bias was quantified by considering reporting of '0' or '5' as the terminal digits in the CPD frequency. The factors influencing it were identified by bivariate and logistic regression analysis. Results: The mean and mode of CPD frequency was 6.7 and 10 respectively. Around 14.5%, 15.1% and 15.2% of daily smokers had reported their CPD frequency as 2, 5 and 10 respectively. Modified Whipple index was estimated to be 226.3 indicating poor data quality. Digit bias was observed in 38% of the daily smokers. Heavy smoking, urban residence, North, South, North- East region of India, less than primary, secondary or higher educated and fourth asset index quintile group were significantly associated with digit bias. Discussion: The present study highlighted poor quality of CPD frequency data in the GATS-India survey and need for its improvement. Modeling of digit preference and smoothing of the CPD frequency data is required to improve quality of data. Marketing of 10 cigarette sticks per pack may influence CPD frequency reporting, but this needs further examination. Exploring alternative methods to reduce digit bias in cross sectional surveys should be given priority.

Study of Summer Season High Temperature Events in Busan (부산지역의 하계 도시열환경의 특성에 관한 연구)

  • Lee, Kwi-Ok;Lee, Hyun-Ju;Lee, Hwa-Woon
    • Journal of Environmental Science International
    • /
    • v.16 no.5
    • /
    • pp.593-602
    • /
    • 2007
  • The frequency of tropical nights and tropical days in Busan during summer season (June-August) from 1995 to 2004 were investigated. When air temperature higher than $25^{\circ}C$ continuously maintains at night in summer, it is called the occurrence of tropical night. Tropical day is defined that maximum air temperature is higher than $30^{\circ}C$, In Jin-Gu and Daeyeon-dong shows a lot of frequency of tropical day and tropical night because there were located in downtown. Relatively, the areas where are located in seaside and riverside show very low frequency. This can be explained the cooling effects of sea and river. The main meteorological characteristics during tropical nights and tropical days is proved pattern of reverse tendency through wind rose. We analyzed heat index and discomfort index during tropical night and tropical day. This study is useful to understand the aspect of urban thermal environment but need some more observation to quantify.

Vibration of SWCNTs: Consistency and behavior of polynomial law index with Galerkin's model

  • Khadimallah, Mohamed A.;Hussain, Muzamal;Khedher, Khaled Mohamed;Bouzgarrou, Souhail Mohamed;Al Naim, Abdullah F.;Naeem, Muhammad Nawaz;Taj, Muhammad;Iqbal, Zafar;Tounsi, Abdelouahed
    • Advances in nano research
    • /
    • v.9 no.4
    • /
    • pp.251-261
    • /
    • 2020
  • In this article, vibration attributes of single walled carbon nanotubes based on Galerkin's method have been investigated. The influence of power law index subjected to different end supports has been overtly examined. Application of the Hamilton's variational principal leads to the formation of partial differential equations. The effects of different physical and material parameters on the fundamental frequencies are investigated for armchair and zigzag carbon nanotubes with clamped-clamped, simply supported and clamped-free boundary conditions. By using volume fraction for power law index, the fundamental natural frequency spectra for two forms of Single-Walled Carbon Nanotubes (SWCNTs) are calculated. The influence of frequencies against length-to-diameter ratios with varying power law index are investigated in detail for these tubes. MATLAB software package has been utilized for extracting tube frequency spectra. The obtained results are confirmed by comparing with available literature.

A Study on the Dietary Habit and Nutritional State to Obesity Index of Adults Living in Daejeon (대전 지역 일부 성인 남녀의 비만도에 따른 식습관 및 영양소 섭취실태)

  • Kim Sung-Hwan;Kim Na-Young;Yea In-Seob
    • Journal of the East Asian Society of Dietary Life
    • /
    • v.15 no.2
    • /
    • pp.152-157
    • /
    • 2005
  • The purpose of this study was to investigate dietary habit and to evaluate nutritional status and obesity index about adults living in Daejon area. This study was conducted with 250 subjects (male 130, female 120) who visited periodically a periodic health center in a general hospital from May to June in 2002. Questionaries were used for studying of dietary habit and food frequency method. Dietary intake was assessed by food frequency method and consumption of foods and nutrients was analyzed. The relationship between dietary habit and obesity were also analyzed. Dietary habit was better in female than mail. There was no significant difference in mean of Broca's index between female ($110.6\pm16.6\%$) and male ($110.0\pm13.7\%$). The obesity group showed low dietary habit score in irregular eating behavior, frequent eating out and over-intake of salty foods. Especially mean intakes of energy were lower than Korean RDA in all groups. All groups except obesity group were deficiency of vitamin A and vitamin $B_{1}$ and calcium.

  • PDF