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The Selection of Appropriate Sampler for the Assessment of Macrobenthos Community in Saemangeum, the West Coast of Korea (새만금 외해역에서 대형 저서동물 군집 조사를 위한 적정 채집기의 선택)

  • 유재원;김창수;박미라;이형곤;이재학;홍재상
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.8 no.3
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    • pp.285-294
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    • 2003
  • To select an appropriate sampler for the environmental monitoring survey in coastal waters of Saemangeum, Jeollabuk-do, a macrobenthic sampling was conducted in April 2002. Employed samplers were dredge (type Charcot), a semi-quantitative sampler and Smith-McIntyre (SM) and van Veen grab (VV) as quantitative ones. One haul was tried for dredge and 3 replicates (0.1 ㎡${\times}$3) for SM and W at each of 11 stations. Comparisons of sediment volume in sampler bucket and of precision of biological parameters (i.e., density, biomass, species number and diversity index, H') were made between SM and VV. Sediment volume was significantly different (SM > VV) at p-value of 0.0050 (paired t-test) and, in average, 3 replicate samples of SM and VV satisfied a precision level of 0.2 by applying 4th root transformation. Patterns of observed and expected species numbers and H' were compared. Dredge-VV samples showed higher affinity than any other pair. Several dominant species in the area were underestimated in dredge samples (e.g., polychaete Heteromastus filiformis. Aricidea assimilis etc.). Quantifying the agreement pattern of multi-species responses was accomplished by estimating correlations between similarity matrices. Correlation between dredge and VV was slightly higher, but near-per-fect matches were found in general. Different ranks and composition among principal species lists were presumably linked to the effect of penetration depth that differs among samplers. Lower level of some species' abundance in VV samples (ca. 50% compared with those of SM) was explained in this context. It seem appropriate to regard the effect as a probable cause of relatively higher correlations in dredge-VV, Overall bio-logica1 features indicated that a better choice could be SM in situations of requiring high data quality. The others work well, however, on observing and defining faunal characteristics and their capability cannot be questionted if we do not expect a first-order quality.

'Nokyang', Whole Crop Forage Barley Cultivar with the Stay-Green Character, Resistance to Viral Disease and High-Yielding (내병 다수 후기녹체성 청보리 신품종 '녹양')

  • Park, Tae-Il;Oh, Young-Jin;Park, Hyoung-Ho;Park, Jong-Chul;Cho, Sang-Kyun;Noh, Jae-Hwan;Kim, Dae-Wook;Song, Tae-Hwa;Chae, Hyun-Seok;Jeung, Jae-Hyun;Hong, Ki-Heung;Bae, Jeong-Suk;Huh, Jae-Young;Ku, Ja-Hwan;Park, Ki-Hun;Han, Ouk-Kyu
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.35 no.1
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    • pp.57-62
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    • 2015
  • "Nokyang" (Hordeum vulgare L.), a new whole-crop silage barley cultivar, was developed by the breeding team at the Department of Rice and Winter Cereal Crop, National Institute of Crop Science, RDA, Korea in 2012. It was derived from combining "Nagyoung" and breeding line "SB77368-B-145". Among the combinations made in 2001, a promising line, "SB01T2017", showed good characteristics in terms of potential forage yield in the yield trial at Iksan from 2007 to 2009. In 2009, the promising line was designated as "Iksan457" and placed in regional yield trials at six locations around Korea for three years from 2010 to 2012, and was released under the name of "Nokyang." It has the growth habit of a group III creeping plant type, with a light-green leaf and common spike. Its average heading and maturing dates were on May 6 and June 4, respectively, which were later than cultivar "Youngyang." "Nokyang" also showed strong winter hardiness, and a resistance to shattering and barley yellow mosaic virus (BaYMV) similar to those of the check cultivar. The best thing among the traits of one is a new good quality with the plant green at the latter growing period. The average forage dry matter (DM) yields in the regional yield trial were about 12.8 and 11.5 MT $ha^{-1}$ in upland and paddy field, respectively, which were higher than those of the check cultivar, by 7% and 2%, respectively. This cultivar would be suitable for an area of the Korean peninsula where the daily minimum temperature in January is above $-8^{\circ}C$.

Assessment of statistical errors of articles published in the Journal of the Korean Academy of Prosthodontics: 2006 - 2010 (대한치과보철학회지에서 볼 수 있는 통계적 오류의 고찰(2006 - 2010))

  • Kang, Dong-Wan;Seo, Yunam;Oh, Nam-Sik;Lim, Hoi-Jeong
    • The Journal of Korean Academy of Prosthodontics
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    • v.50 no.4
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    • pp.258-270
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    • 2012
  • Purpose: Use of inappropriate statistical methods may lead to incorrect conclusions and a waste of valuable resources. The goal of this study was to assess the frequency and the types of several common statistical errors in the published articles of the Journal of the Korean Academy of Prosthodontics (JKAP) for a 5-year period. Materials and methods: Of 336 articles in the JKAP published from 2006 to 2010, 255 articles using statistics were reviewed and classified by statistical method and year. The frequency and types of the statistical methods were examined, and the statistical errors were evaluated by the appropriateness of the experimental design, assumption check, independent outcomes, proper sample size and suitable use of statistical method. Statistical guidelines were completed based on the appropriateness. Results: Of the 255 articles using statistics, 193 articles (75.9%) used inferential statistics and 153 articles used SPSS statistical software (60.0%). Of the articles using inferential statistics, the three most frequently used statistical methods were ANOVA (41.5%), t-test (20.0%), and the nonparametric method (16.9%). The average rate of statistical errors was 61.2 percent, similar to the rate reported by several studies completed for the medical journal. Conclusion: After the whole analysis of the difference among the groups, post-hoc tests for the pairwise comparisons are required. The optimal sample size calculation is an essential part of this study protocol. To minimize the occurrence of statistical errors, statistical guidelines were developed according to each statistical test procedure and will contribute to the academic improvement in the JKAP.

Evaluation of color matching ability according to the color temperature and the experience of practitioner (색 온도 및 술자의 숙련도에 따른 비색 능력 평가 원저)

  • Kim, Ji-Hyun;Kim, Sun-Jai;Lee, Keun-Woo;Shim, June-Sung;Yoon, Joonho
    • The Journal of Korean Academy of Prosthodontics
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    • v.50 no.4
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    • pp.299-304
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    • 2012
  • Purpose: The aim of this study is to investigate the effect of different experience level and different light source on shade selection ability comparing prosthodontist group and dental student group under 4,000 K and 5,500 K light. Materials and methods: After color difference of Vitapan 3D-master shade guides was measured, 3 sets of 5 shade tabs were selected with similar value but have different chroma (set a, b, c). Also 3 sets of 5 shade tabs were selected with similar chroma but have different values (set d, e, f). Under 4,000 K and 5,500 K light sources, ten prosthodontists and ten dental students were allowed to match in one set of 5 tabs the same shade tab with the tab which was originally selected in the other set of 5 tabs. Color differences of original tab and matched tab were measured by spectrophotometer and the shade selection ability was evaluated with those data. Evaluation of color difference value was performed in regard to different light conditions and different level of experience, followed by t-test with 95% confidence interval. Results: Color difference values under 4,000 K and 5,500 K light source were $1.62{\pm}2.0$, and $1.33{\pm}1.7$ respectively. In addition, color difference values of prosthodontist group and dental student group were $1.34{\pm}1.7$, and $1.61{\pm}2.0$ respectively. Difference of shade selection ability was not found under either different light sources (P=.398), or different experience level (P=.221). Conclusion: Level of experience did not affect on the shade selection ability when prosthodontists and dental students matched the shades with the same shade tab under the same light source.

A study on the impacts of infection control education on dental hygienists' perceptions for hepatitis type B and their practices to prevent infection (감염관리교육이 서울지역 치과위생사의 B형 간염에 대한 인식 및 감염방지행위 실천에 미치는 영향에 관한 연구)

  • Kim, Bo-Young;Park, Ji-Man;Park, Eun-Jin
    • The Journal of Korean Academy of Prosthodontics
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    • v.52 no.4
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    • pp.287-297
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    • 2014
  • Purpose: The purpose of this study is to examine the impacts of infection control education on dental hygienists' perceptions for hepatitis B and their behaviors. Materials and methods: Study participants were chosen by random selection among dental hygienists working in Seoul, Korea. A total of 150 questionnaires were sent out for the survey from April 2013 to May 2013, of which 140-excluding incomplete responses-were used for the study. Chi-square tests and t-tests were used (SPSS 19.0), and post-hoc analysis was performed as well. The maximum significance level was 0.05. Results: Average 1.53 times infection control education was taken, but dental hygienists' perceptions for hepatitis B and their behaviors did not show statistical differences whether the education was done or not. Practices to prevent infection showed differences depending on categories, especially disinfection and sterilization were well performed by educated group. The most common reasons for not taking the education and noncompliance with infection prevention guidelines are lack of time and opportunity due to busy schedule. Conclusion: 1. The more highly educated, the greater number of patients per day, and the greater size of hospitals, the better infection control education was conducted. 2. Although hepatitis B is one of the most common chronic liver diseases in Korea, no significant correlation between perceptions of hepatitis B and infection control education was found. 3. Dental hygienists who received infection control education performed more efficient practices for protection against infections than those who did not.

Comparative study of fracture strength depending on the occlusal thickness of full zirconia crown (완전 지르코니아 크라운의 교합면 두께에 따른 파절강도의 비교 연구)

  • Jang, Soo-Ah;Kim, Yoon-Young;Park, Won-Hee;Lee, Young-Soo
    • The Journal of Korean Academy of Prosthodontics
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    • v.51 no.3
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    • pp.160-166
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    • 2013
  • Purpose: The purpose of this study was to compare the fracture strength of traditional metal-ceramic crowns and full zirconia crowns according to the occlusal thickness. Materials and methods: A mandibular first molar resin tooth was prepared with 1.5 mm occlusal reduction, 1.0 mm rounded shoulder margin and $6^{\circ}$ taperness in the axial wall. Duplicating the resin tooth, 64 metal dies were fabricated. 48 full zirconia crowns were fabricated using Prettau zirconia blanks by ZIRKONZAHN CAD/CAM and classified into six groups according to the occlusal thickness (0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1.0 mm). 16 metal-ceramic crowns were fabricated and classified into two groups according to the occlusal porcelain thickness (1.0 mm, 1.5 mm). All crowns were cemented on each metal die and mounted in a universal testing machine. The load was directed at the functional cusp of each specimen until catastrophic failure occurred. One-way ANOVA, Tukey multiple comparison test (${\alpha}=.05$) and t-test (${\alpha}=.05$) were used. Results: The results were as follows. 1. The test 1 group (646.48 N) showed the lowest fracture strength (P<.05), and the value of the test 2.3.4.5 groups (866.40 N, 978.82 N, 1196.82 N, 1222.41 N) increased as thickness increased, but no significant difference were found with the groups (P>.05). The value of test 6 group (1781.24 N) was significantly higher than those of the other groups (P<.05). 2. There were no significant differences of the fracture strength of metal ceramic crowns according to occlusal porcelain thickness 1.0 mm (2515.71 N) and 1.5 mm (3473.31 N) (P<.05). Conclusion: Full zirconia crown needs to be 1.0 mm or over in occlusal thickness for the posterior area to have higher fracture strength than maximum bite force.

The Effect of Ginseng Saponins on the Biosynthesis of Prostaglandins (인삼 Saponin이 Prostaglandin 대사에 미치는 영향)

  • Park C.W.;Lee S.H.
    • Proceedings of the Ginseng society Conference
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    • pp.77-80
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    • 1988
  • The effects of ginseng saponins and some phenolic acids on the in vitro biosynthesis of prostaglandins was examined in order to identify the role of some ginseng components on the regulaion of arachidonic acid metabolism. The productions of prostaglandin $E_2(PGE_2).$ prostaglandin $F_2{\alpha}(PGF_2{\alpha}).$ thromboxane $B_2(TxB_2)$ and 6-keto-prostaglandin $F_1{\alpha}(6-keto-PGF_1{\alpha})$ from $[^3H]-arachidonic$ acid were evaluated with rabbit kidney microsome. human platelet homogenate and bovine aortic microsome. The amounts of the total cyclooxy-genase products from arachidonic acid did't show significant changes in the presence of ginseng saponins. Panaxadiol. panaxatriol and all of the ginsenosides used in these experiments reduced the formation of $TxB_2.$ while increased the $6-keto-PGF_1{\alpha}$ production dose dependently. Ginseng saponins did't inhibit the ADP($10{\mu}M$) induced platelet aggregation. but sodium arachidonate (0.5 mM) induced platelet aggregation. but sodium arachidonate (0.5 mM) induced platelet aggregation was signiticantly inhibited. These findings suggest that ginseng saponins seem to playa role in the regulation of the arachidonate metabolism. probably by affecting the divergent biosynthetic pathway of prostaglandins from endoperoxide.

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Warm Season Hydro-Meteorological Variability in South Korea Due to SSTA Pattern Changes in the Tropical Pacific Ocean Region (열대 태평양 SSTA 패턴 변화에 따른 우리나라 여름철 수문 변동 분석)

  • Yoon, Sun-kwon;Kim, Jong-Suk;Lee, Tae-Sam;Moon, Young-IL
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.36 no.1
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    • pp.49-63
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    • 2016
  • In this study, we analyzed the effects of regional hydrologic variability during warm season (June-September) in South Korea due to ENSO (El $Ni{\tilde{n}}o$-Southern Oscillation) pattern changes over the Tropical Pacific Ocean (TPO). We performed composite analysis (CA) and statistical significance test by Student's t-test using observed hydrologic data (such as, precipitation and streamflow) in the 113 sub-watershed areas over the 5-Major River basin, in South Korea. As a result of this study, during the warm-pool (WP) El $Ni{\tilde{n}}o$ year shows a significant increasing tendency than normal years. Particularly, during the cold-tongue (CT) El $Ni{\tilde{n}}o$ decaying years clearly decreasing tendency compared to the normal years was appeared. In addition, the La $Ni{\tilde{n}}a$ years tended to show a slightly increasing tendency and maintain the average year state. In addition, from the result of scatter plot of the percentage anomaly of hydrologic variables during warm season, it is possible to identify the linear increasing tendency. Also the center of the scatter plot shows during the WP El $Ni{\tilde{n}}o$ year (+17.93%, +26.99%), the CT El $Ni{\tilde{n}}a$ year (-8.20%, -15.73%), and the La $Ni{\tilde{n}}a$ year (+8.89%, +15.85%), respectively. This result shows a methodology of the tele-connection based long-range water resources prediction for reducing climate forecasting uncertainty, when occurs the abnormal SSTA (such as, El $Ni{\tilde{n}}o$ and La $Ni{\tilde{n}}a$) phenomenon in the TPO region. Furthermore, it can be a useful data for water managers and end-users to support long-range water-related policy making.

Effects of supplementation of dietary betaine on apparent nutrient digestibility and physiological responses in finishing pigs (사료 내 비테인 첨가 급여가 비육돈의 영양소 소화율 및 생리학적 변화에 미치는 영향)

  • Kim, Ki-Hyn;Kim, Kwang-Sik;Kim, Doo-Wan;Sa, Soo-Jin;Kim, Young-Hwa
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.12
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    • pp.407-414
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    • 2016
  • This study was conducted to investigate the effects of supplementation of dietary betaine on nutrient digestibility and physiological responses in finishing pigs. A total of twelve pigs with a body weight of $80.1{\pm}3.7kg$ were individually caged, and randomly assigned to one of the two experimental diets containing 0 (control) or 5 g/kg (treatment) of the betaine in a $2{\times}2$ Latin square design. The experimental period was 14 days-7 days adaptation and 7 days trial period-per phase. All data for the difference between control and treatment groups were statistically analyzed by student's t-test. Dry matter and crude protein digestibility in the treatment group were significantly improved by 1% and 1.3%, respectively, as compared with those in the control (p<0.05). The apparent absorption of dietary energy was increased from 82.3% to 83.7% by dietary betaine supplementation. Thus, the retention of energy was also significantly increased to above 6% in the treatment group compared with the control group (control 4,057 vs treatment 4,314 kcal; p<0.01). The physiological parameters indicating serum biochemical contents and stress-, immune-, and inflammatory- responses were not changed by the supplementation of dietary betaine. In conclusion, dietary betaine improves the nutrient digestibility without any negative effects in terms of physiology in finishing pigs. It suggests that the supplementation of dietary betaine may increase the productivity through the improvement of weight gain and feeding efficiency.

Effects of the 26-weeks Obesity Management Program on Obesity Index, Self-esteem, Self-efficacy, and Body Image among Obese Elementary School Children (초등학교 비만아동을 위한 26주-비만관리프로그램이 비만지수와 자아존중감, 자기효능, 및 신체상에 미치는 효과에 미치는 효과)

  • Lee, Jin Hee;Oh, Sangeun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.9
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    • pp.83-93
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    • 2016
  • This study was conducted to develop a 26-week obesity management program and examine the effects of this program on obesity index (body mass index, fat mass percentage, and triglyceride) and psychological variables, self-esteem, dietary self-efficacy, physical activity self-efficacy, and body image among 46 4th-6th obese elementary school children with a BMI above $20kg/m^2$ using a nonequivalent control group quasi-experimental design (experimental group=23, control group=23). This program included a 12-week intensive course (12 times for group education on obesity, exercise, and nutrition, 36 times for practicing diet and physical exercise, and 5 times for psychological counseling) and a 14-week follow-up course (3 times for group education, 3 times for checking diet and physical exercise, and 1 time for psychological counseling. The collected data were analyzed by the Kolmogorov-Smirnov test, chi-squared test, Fisher's exact probability, t-test, and ANCOVA. There were above normal values in body mass index ($20kg/m^2$), fat mass percentage (15-20%), and triglyceride tolerance ($90mg/d{\ell}$) in experimental group and control group. The body mass index (F=94.869, p<.001), fat mass percentage (F=37.361, p<.001), and triglyceride tolerance (F=7.907, p= .007) were significantly lower, while self-esteem (F=19.661, p<.001), dietary self-efficacy (F=16.942, p<.001), physical activity self-efficacy (F=9.363, p= .004), and body image (F=9.782, p= .003) were significantly higher in the experimental group than the control group after 26 weeks. This study provides evidence that the 26-weeks obesity management program is an effective nursing intervention for managing obesity and psychological variables of obese elementary school children.