• Title/Summary/Keyword: statistical variations

Search Result 490, Processing Time 0.026 seconds

Normative Measurements of Grip and Pinch Strengths of 21st Century Korean Population

  • Shim, Jin Hee;Roh, Si Young;Kim, Jin Soo;Lee, Dong Chul;Ki, Sae Hwi;Yang, Jae Won;Jeon, Man Kyung;Lee, Sang Myung
    • Archives of Plastic Surgery
    • /
    • v.40 no.1
    • /
    • pp.52-56
    • /
    • 2013
  • Background Measuring grip and pinch strength is an important part of hand injury evaluation. Currently, there are no standardized values of normal grip and pinch strength among the Korean population, and lack of such data prevents objective evaluation of post-surgical recovery in strength. This study was designed to establish the normal values of grip and pinch strength among the healthy Korean population and to identify any dependent variables affecting grip and pinch strength. Methods A cross-sectional study was carried out. The inclusion criterion was being a healthy Korean person without a previous history of hand trauma. The grip strength was measured using a Jamar dynamometer. Pulp and key pinch strength were measured with a hydraulic pinch gauge. Intra-individual and inter-individual variations in these variables were analyzed in a standardized statistical manner. Results There were a total of 336 healthy participants between 13 and 77 years of age. As would be expected in any given population, the mean grip and pinch strength was greater in the right hand than the left. Male participants (137) showed mean strengths greater than female participants (199) when adjusted for age. Among the male participants, anthropometric variables correlated positively with grip strength, but no such correlations were identifiable in female participants in a statistically significant way. Conclusions Objective measurements of hand strength are an important component of hand injury evaluation, and population-specific normative data are essential for clinical and research purposes. This study reports updated normative hand strengths of the South Korean population in the 21st century.

Interannual Variability of Sea Water Temperatures in the Southern Waters of the Korean East Sea (한국 동남해역의 장주기 수온변동)

  • Ro, Young Jae
    • 한국해양학회지
    • /
    • v.24 no.1
    • /
    • pp.1-14
    • /
    • 1989
  • This study analyzes the interannual periodicity by using the statistical techniques of probability, spectral analysis, empirical orthogonal function analysis (EOF), and coherency analysis. The data base for this study is the time series of 1971-1985 temperature, salinity in the southern waters of the East Sea, 1960-1986 mean sea level at Pusan and Izuhara, and 1960-1986 sea level atmospheric pressure at Pusan. The appearances of anomalous temperatures higher and lower than 15-year mean monthly average with one standard deviation are about 30% of total data. The significant interannual period for temperature, salinity and sea level fluctuation is 36.6, and 23.3 months. The empirical orthogonal function analyses show that the 1st mode of the EOFs is responsible for more than 90% of total variance of the surface temperature variations, while in near-bottom waters, the relative importance of the higher EOF modes is much greater explaining more than 30% of total variance. The coherency between normalized temperatures and salinities is significant at the interannual period of 36.6 and 21.3 months.

  • PDF

Effect of a Self-Stretching Exercise on Musculoskeletal Symptom and Job Stress for Care Helpers (자가 신장 운동이 요양보호사의 근골격계 증상 및 직무 스트레스에 미치는 효과)

  • Wang, Joong-San;Kim, Nyeon-Jun;Kim, Yong-Youn;An, Ho-Jung;Kim, Ji-Sung
    • Journal of the Korean Society of Physical Medicine
    • /
    • v.8 no.2
    • /
    • pp.183-192
    • /
    • 2013
  • PURPOSE: The purpose of this study was to research the effect of self-Stretching Exercise on musculoskeletal Symptom and job Stress for care helpers who work at geriatric hospital and come up to NIOSH standard. METHODS: The effect of self-Stretching Exercise was measured using 'musculoskeletal symptom survey table' and 'Job stress measurement scale for korean' from the Korea Occupational Safety and Health Agency(KOSHA) for 40 care helpers. The paired t-test and independent t-test was used for statistical analysis. RESULTS: The pracitce of Self-Stretching Exercise was showed significant effect reducing the stress for care helper's total job Stress and inappropriate compensation, job instability, job requirement, relationship conflict, physical environment(p<.05), and significant difference for their total score, relationship conflict, structure and organization, physical environment, inappropriate compensation improvement on variations on job stress in groups(p<.05). However, self-Stretching Exercis was showed no significant effect on physcial burden. CONCLUSION: The self-Stretching Exercise was the most effect way to reduce Musculoskeletal Symptom and job Stress for a care helpers through the guidance of physical therapist.

The Relationship between Preferred Hairstyle and Pursued-Image of Hairstyle according to Demographic Characteristics: Focusing on Hair Salon Visitors (인구통계적 특성에 따른 선호 헤어스타일 및 헤어추구이미지와의 관계: 미용실 방문객을 중심으로)

  • Kim, Sunmi;Ha, Kyungyun
    • Journal of Fashion Business
    • /
    • v.18 no.2
    • /
    • pp.66-79
    • /
    • 2014
  • The purpose of this study was to find out the difference between preferred hairstyle and pursued-image of hairstyle according to demographic characteristics. The method of this study is a content analysis and survey research using a questionnaire, which consisted of items of pursued-image of hairstyle, preferred hairstyle and demographic characteristics. 450 women were selected as subjects of this study; they were randomly selected from hair salon located in Seoul, Inchon and Bundang. For the material analysis, We used the statistical program of SPSS 12.0; frequencies, factor nalysis, one-way ANOVA and Duncan's multiple range test, T Test and ${\chi}^2$ Test were carried out as the methods of analysis. The research findings were as follows. First, the results of hairstyles according to the content analysis usually resulted 5 hairstyles, such as cuts and crew cut, bobbed hair, long layered hair styles and nonelayered long hair styles. Second, under the survey regarding the difference of preferred hairstyle and pursued-image of hairstyle according to demographic characteristics. variety of hair styles due to the subjects were more willing to try a consciousness about other's suggestions and how they are portrayed. Moreover a low level of education was ralated to a attempting a variety of styles, considering their social life. Subjects with higher age, education level and salary preferred a glamorous image as well as crew cuts. Which made them look younger. However, when they were younger, they preferred long nonelayered hair styles. In conclusion, age, average monthly income and education level are important variations affecting the property of change in hairstyles and pursued-image of hairstyles.

Long-term Changes of Physicochemical Water Quality in Lake Youngrang, Korea

  • Bhattrai, Bal Dev;Kwak, Sungjin;Choi, Kwansoon;Heo, Woomyung
    • Korean Journal of Ecology and Environment
    • /
    • v.50 no.1
    • /
    • pp.169-185
    • /
    • 2017
  • Physicochemical properties of water quality were analyzed to understand the long-term variations in Lake Youngrang from 1998 to 2015. Nonparametric statistical methods were applied to deduct correlation among water quality parameters and water quality trend. In total observations(N=64), the Secchi depth (SD) transparency showed significant positive correlation with salinity (r=0.458) and highly significant negative correlation with chlorophyll-a (r= -0.649) for p<0.0001 in two-tailed test of Spearman's rank correlation. Significant negative correlations of SD were observed with chemical oxygen demand (COD), total phosphorus (TP) and total nitrogen (TN). These correlation patterns were very similar in rainy (N=25) and non-rainy (N=39) periods too. Chlorophyll-a (Chl-a) had significant correlation with COD. Sen's slope test was performed along with Mann-Kendall trend test (significance ${\alpha}=0.05$, two-tailed) to find water quality trend. Positive trends were observed for SD and salinity with Sen's slopes 0.012 and 0.385, respectively (p<0.0001). Negative significant trends were observed for total nitrogen (TN) and Chl-a with Sen's slopes -0.02 (p<0.0001) and -0.346 (p=0.0010), respectively. Temperature, COD and phosphorus components had no trends. Carlson's trophic state index (TSI) for SD, TP and Chl-a were obtained in the ranges of 46~80, 37~82 and 39~82, respectively. Trophic index values suggest that Lake Youngrang was mesoeutrophic to eutrophic and there could be possibility of anoxia during the summer and dominance of blue-green algae. Excess nutrient inputs from external and internal sources were the causes of eutrophication in this lake. The findings of this study would be helpful to recognize water quality variables to manage the water body.

A Study on the Comparison of Atmospheric Concentrations of Volatile Organic Compounds in a Large Urban Area and a Sub-Urban Area (대도시 및 주변 교외지역의 대기 중 휘발성 유기화합물 농도 비교에 관한 연구)

  • Park, Ji-Hyae;Seo, Young-Kyo;Baek, Sung-Ok
    • Journal of Korean Society for Atmospheric Environment
    • /
    • v.22 no.6
    • /
    • pp.767-778
    • /
    • 2006
  • This study was carried out to evaluate the temporal variations of VOCs at an urban site, and to compare the concentrations of VOCs at an urban site in Daegu with those at a suburban site in Gyeongsan. Three hourly VOC samples in the ambient air were collected using a sequential tube sampler (STS 25, Perkin Elmer) throughout two weeks during May and July representing spring and summer seasons, respectively. The VOC concentrations were determined by an automatic thermal desorption apparatus with GC/MS analysis. A total of 12 VOCs of environmental concern were determined, which are chloroform, benzene, trichloroethylene, toluene, tetra-chloroethylene, ethylbenzene, m+p-xylenes, o-xylene, styrene, 1,3,5- and 1,2,4-trimethylbenzenes. Among 12 target VOCs, the most abundant compound appeared to be toluene, being followed by xylenes. The mean concentrations at the urbn site were 1.2 pub for benzene and 20.4 ppb for toluene (n=221) while the mean levels at the suburban site were 0.9 ppb and 4.3 ppb for benzene and toluene (n=96), respectively. The urban site concentrations were typically several-fold higher than those measured at the suburban site. It was found that general trends of VOC levels were significantly dependent on traffic conditions at the sampling site since VOC concentrations were at their maximum during rush hours, i.e. $9{\sim}12a.m$ and $6{\sim}9p.m$. Statistical investigations were conducted to investigate any significant relationships between VOC concentrations and affecting factors. Calculated correlation coefficients among VOCs were positively significant at a level of 0.05 in most cases. Increased concentrations of toluene in the urban site were estimated to reflect the effect of large industrial sources, mainly from textile industry.

Temporal and Spatial Wind Information Production and Correction Algorithm Development by Land Cover Type over the Republic of Korea (한반도 시공간적 바람정보 생산과 토지피복별 보정 알고리즘 개발)

  • Kim, Do Yong;Han, Kyung Soo
    • Journal of Korean Society for Geospatial Information Science
    • /
    • v.20 no.3
    • /
    • pp.19-27
    • /
    • 2012
  • Wind is an important variable for various scientific communities such as meteorology, climatology, and renewable energy. In this study, numerical simulations using WRF mesoscale model were performed to produce temporal and spatial wind information over the Republic of Korea during 2006. Although the spatial features and monthly variations of the near-surface wind speed were well simulated in the model, the simulated results overestimated the observed values as a whole. To correct these simulated wind speeds, a regression-based statistical algorithm with different constants and coefficients by land cover type was developed using the satellite-derived LST and NDWI. The corrected wind speeds for the algorithm validation showed strong correlation and close agreement with the observed values for each land cover type, with nearly zero mean bias and less than 0.4 m/s RMSE. Therefore, the proposed algorithm using remotely sensed surface observations may be useful for correcting simulated near-surface wind speeds and producing more accurate wind information over the Republic of Korea.

Association between Single Nucleotide Polymorphisms of the Fibrinogen Alpha Chain (FGA) Gene and Type 2 Diabetes Mellitus in the Korean Population

  • Hwang, Joo-Yeon;Ryu, Min-Hyung;Go, Min-Jin;Oh, Berm-Seok;Cho, Yoon-Shin
    • Genomics & Informatics
    • /
    • v.7 no.2
    • /
    • pp.57-64
    • /
    • 2009
  • Fibrinogen alpha chain (FGA), a subunit of fibrinogen, might be a potential player for type 2 diabetes mellitus (T2DM), since the plasma levels of fibrinogen is known to be related to the incidence of T2DM. To elucidate the potential role of FGA in T2DM, we investigated whether FGA genetic variations are relevant in T2DM in the Korean population. Seven FGA single nucleotide polymorphisms (SNPs) were genotyped in Ansung and Ansan cohorts (474 T2DM subjects and 470 normal controls) in Korea. The association between SNPs and T2DM was determined by logistic regression analysis. Genetic relevance of SNPs to T2DM-related phenotypes was investigated by multiple linear regression analysis. Statistical analysis revealed that among seven FGA SNPs, significant associations with T2DM were observed in FGA rs2070011 (p=0.013-0.034, OR=0.72${\sim}$0.79), rs6050 (p=0.026${\sim}$0.048, OR=1.24${\sim}$1.37), and rs2070022 (p=0.016${\sim}$0.039, OR=0.70${\sim}$0.72). Two SNPs, rs2070011 and rs6050, also showed significant association with T2DM-related phenotypes such as triglyceride (p=0.005${\sim}$0.011 for rs2070011 and p=0.003${\sim}$0.008 for rs6050), total cholesterol (p=0.01 for rs2070011 and p=0.024 for rs6050) and fasting glucose (p=0.035${\sim}$0.036 for rs2070011 and p=0.048 for rs6050) in 470 normal controls. Our association study implies that FGA might be an important genetic factor in T2DM pathogenesis in the Korean population by affecting plasma lipid and glucose levels.

Changes in Acceleration at the Upper Thigh and Ankle with Variations in Gait Speed and Walkway Slope (보행 속도와 보행로 경사에 따른 대퇴상부와 발목상부에서의 가속도의 변화)

  • Kwon, Yu-Ri;Kim, Ji-Won;Kang, Dong-Won;Tack, Gye-Rae;Eom, Gwang-Moon
    • Korean Journal of Applied Biomechanics
    • /
    • v.20 no.2
    • /
    • pp.191-196
    • /
    • 2010
  • The purpose of this study was to investigate the effect of gait speed and walkway slope on the body acceleration, for the future validation of using an accelerometer in the estimation of energy consumption. Ten young healthy subjects with accelerometers on the upper thigh and ankle walked on a treadmill at 9 conditions(three speeds ${\times}$ three slopes) for 5 minutes. Acceleration signals of four directions, i.e. anterior-posterior(AP), medio-lateral(ML), superior-inferior(SI) and vector sum(VS) directions, of each sensor were measured, and root means squared(RMS) values of them were used as analysis variables. As statistical analysis, repeated measure two-way ANOVA was performed for RMS accelerations at each attachment sites, with slope and velocity as independent factors. At both the upper thigh and ankle, RMS acceleration of all directions were affected by gait velocities(p<.001) showing greater accelerations for higher velocities. Contrary to expectations, no slope effect existed in RMS accelerations at hip. Moreover, RMS acceleraion at ankle decreased with slope in SI and VS directions(p<.01). These results suggests that RMS acceleration cannot reflect the change in physical activity due to the change in walkway slope.

PD Signal Time-Frequency Map and PRPD Pattern Analysis of Nano SiO2 Modified Palm Oil for Transformer Insulation Applications

  • Arvind Shriram, R.K.;Chandrasekar, S.;Karthik, B.
    • Journal of Electrical Engineering and Technology
    • /
    • v.13 no.2
    • /
    • pp.902-910
    • /
    • 2018
  • In recent times, development of nanofluid insulation for power transformers is a hot research topic. Many researchers reported the enhancement in dielectric characteristics of nano modified mineral oils. Considering the drawbacks of petroleum based mineral oil, it is necessary to understand the dielectric characteristics of nanofluids developed with natural ester based oils. Palm oil has better insulation characteristics comparable to mineral oil. However very few research reports is available in the area of nanofluids based on palm oil. Partial discharge (PD) is one of the major sources of insulation performance degradation of transformer oil. It is essential to understand the partial discharge(PD) characteristics by collecting huge data base of PD performance of nano modified palm oil which will increase its confidence level for power transformer application. Knowing these facts, in the present work, certain laboratory experiments have been performed on PD characteristics of nano $SiO_2$ modified palm oil at different electrode configurations. Influence of concentration of nano filler material on the PD characteristics is also studied. Partial discharge inception voltage, Phase resolved partial discharge (PRPD) pattern, PD signal time-frequency domain characteristics, PD signal equivalent timelength-bandwidth mapping, Weibull distribution statistical parameters of PRPD pattern, skewness, repetition rate and phase angle variations are evaluated at different test conditions. From the results of the experiments conducted, we came to understand that PD performance of palm oil is considerably enhanced with the addition of $nano-SiO_2$ filler at 0.01%wt and 0.05%wt concentration. Significant reduction in PD inception voltage, repetition rate, Weibull shape parameter and PD magnitude are noticed with addition of $SiO_2$ nanofillers in palm oil. These results will be useful for recommending nano modified palm oil for power transformer applications.