• Title/Summary/Keyword: Method of Difference Analysis

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Biomass, Net Production and Biomass Estimation Equations in Some Natural Quercus Forests (주요 참나무류 천연림(天然林)의 물질생산(物質生産) 및 현존량추정식(現存量推定式)에 관(關)한 연구(硏究))

  • Park, In Hyeop;Moon, Gwang Sun
    • Journal of Korean Society of Forest Science
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    • v.83 no.2
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    • pp.246-253
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    • 1994
  • Four Quercus forests in Mt. Mohu were studied to investigate biomass, net production and effective biomass estimation method. Five $10m{\times}10m$ quadrats were set up, ten sample trees were cut and roots of three sample trees were excavated for dimension analysis in each forest. There was little difference in accuracy among three allometric biomass regression models of logWt=A+BlogD, $logWt=A+BlogD^2H$ and logWt=A+BlogD+ClogH, where Wt, D and H were dry weight, DBH and height, respectively. Analysis of covariance showed that there were no significant differences among slopes and intercepts of allometric biomass regressions, logWt=A+BlogD, of four Quercus species. Biomass of Q. acutissima, Q. nariabilis, Q. serrata and Q. mongolica forests were 164.0, 158.9, 115.3 and 118.9t/ha, respectively. Net production of Q. acutissima, Q. variabilis. Q. serrata and Q. mongolica forests were 25.0, 23.2, 14.5 and 12.6t/ha/yr., respectively. The proportion of roots to total biomass and total net production of Q. mongolica forest was higher than that of three other species forests. Net assimilation ratio of Q. acutissima, Q. variabilis, Q. serrata and Q. mongolica forests were 2.87, 2.80, 3.20 and 2.95, respectively. Relatively less leaf biomass of Q. serrata and Q. mongolica forests were the reason why total biomass and total net production of Q. serrata and Q. mongolica forests were less than those of Q. acutissima and Q. variabilis.

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Effects of specimens dimension on the flexural properties and testing reliability of dental composite resin (치과용 복합레진의 굽힘 특성과 시험 신뢰도에 미치는 시편 크기의 영향)

  • Im, Yong-Woon;Hwang, Seong-sig;Kim, Sa-hak;Lee, Hae-Hyoung
    • Korean Journal of Dental Materials
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    • v.44 no.3
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    • pp.273-280
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    • 2017
  • The aim of the present study was to investigate the effects of specimen dimension on the flexural properties and testing reliability of dental composite resin. The composite resin was prepared experimentally by mixing a resin matrix with silanated micrometer glass filler at 50 vol%. Flexural specimens with various dimension in specimen's width were fabricated by light curing using a split metal mold; $25{\times}2{\times}2mm$, $25{\times}2{\times}4mm$, $25{\times}2{\times}6mm$ in length ${\times}$ height ${\times}$ width. The flexural strength and modulus were determined according to ISO 4049 test protocol at a span length of 20 mm (normal-flexural strength; NFS). Another flexural test was conducted using mini-sized specimens ($12{\times}2{\times}2mm$, $12{\times}2{\times}4mm$, $12{\times}2{\times}6mm$) from the broken specimens at a span length of 10 mm (mini-flexural strength; MFS). Data were analyzed with ANOVA and Duncan's post-hoc test and the test reliability was evaluated by Weibull analysis. Results showed that there are generally no significant difference in flexural strength with the increase in the specimen width in NFS and MFS tests. However, the test reliability of flexural strength based on Weibull analysis was largely changed with the variables in the dimension of width and span length. The flexural modulus of NFS was increased as the dimension of specimens width increased while there was no trend in flexural modulus of MFS test. Overall results recommend that the evaluation of flexural properties and the reliability of dental composite resins should be performed with more than one test method.

Estimation Model for Simplification and Validation of Soil Water Characteristics Curve on Volcanic Ash Soil in Subtropical Area in Korea (난지권 화산회토양의 토색별 토양수분 특성곡선 및 단일화 추정모형)

  • Hur, Seung-Oh;Moon, Kyung-Hwan;Jung, Kang-Ho;Ha, Sang-Keun;Song, Kwan-Cheol;Lim, Han-Cheol;Kim, Geong-Gyu
    • Korean Journal of Soil Science and Fertilizer
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    • v.39 no.6
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    • pp.329-333
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    • 2006
  • Most of volcanic ash soils in South Korea are distributed in Jeju province which is an island placed on southern part of Korea and has steep slope mountain area. There are many soils containing high contents of organic matter (OM) derived from volcanic ash in Jejudo, also. Therefore, irrigation and drainage in volcanic ash soil different with general soil which has low OM content have to be applied with another management way, but studies searching appropriate methods for them are set on insufficient situation because the area of volcanic ash soil in South Korea is only 1.3% (130,000ha). This study was conducted for analysis of soil water content and irrigation quantity appropriate for crops cultivated in volcanic ash soil with high OM content. Although soils with different soil color have the same soil texture, soil water characteristics curve by soil color showed the difference of water retention capability by OM content. But, this characteristics classified with soil color could be unified by scaling technique with similitude analysis method which get dimensionless water content using a present water content, a residual water content and saturated water content (or water content at 10kPa). A relation of gravimetric soil water content (GSWC) and dimensionless water content by the results showed a form of power function. The dimensionless water content (DWC) express a relative saturation degree of present water content. This was also expressed by van Genuchten model which describe the relation between relative saturation degrees and matric potentials. These results on soil water characteristics curve (SWCC) of volcanic ash soil will be the basic of irrigation plan in area having high organic contents into soil.

The effect of dental hygiene students' knowledge and attitude toward the elderly on the discrimination of the elderly (치위생학과 학생들의 노인에 대한 지식 및 태도가 노인차별주의에 미치는 영향)

  • Young-Sun Kim;Jung-Hwa Lee
    • Journal of Korean Dental Hygiene Science
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    • v.6 no.2
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    • pp.129-139
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    • 2023
  • Background: The elderly population aged 65 or older in Korea is expected to continue to increase to 18.4% in 2023, and to enter a super-aged society at 20.6% in 2025. In clinical practice, the elderly discrimination of dental hygienists may experience difficulties during dental hygiene treatment due to an increase in the number of elderly patients due to aging, which can lead to maladjustment to work and turnover, so education on the understanding of the elderly is essential for students in the Department of Dentistry, who are prospective dental hygienists. Accordingly, a study was conducted to prepare for a super-aged society by studying the relationship between elderly discrimination and the knowledge and attitudes of the elderly, and to change the curriculum of universities and develop programs related to the elderly. Method: 204 students enrolled in the Department of Dentistry in D area were analyzed using the SPSS/WIN 25.0 program. The subject's geriatric discrimination, knowledge about the elderly, and attitude toward the elderly were calculated as the mean and standard deviation. T-test and one-way ANOVA were performed to verify the difference in geriatric discrimination according to the general characteristics of the subject, with a Scheffe' test applied for post-hoc analysis. Correlation analysis was conducted on the subject's geriatric discrimination, knowledge about the elderly, and attitudes toward the elderly. Results: Geriatrics scored 2.03±0.36 out of 4. Knowledge about the elderly was categorized as follows: physical domain 0.57±0.15; social domain 0.36±0.17; and psychological domain 0.35±0.20. The attitude toward the elderly was 3.86±0.27. Knowledge of the elderly averaged 11.27±3.30 points out of 25. The question with the highest percentage of correct answers to knowledge about the elderly was 'physical strength tends to decrease with age', which was 93.1%. The attitude toward the elderly according to the general characteristics of the study subjects showed significant differences in gender (p=0.040), age (p=0.026), and life experience with grandparents (p=0.001). The elderly discrimination of the study subjects showed a negative correlation in both attitude and knowledge toward the elderly, and among the elderly discrimination, there was a high positive correlation with regard to emotional avoidance (r=.892, p<0.001). Conclusion: College students are the leading players in caring for the elderly and are directly affected by aging social problems. Therefore, it is considered necessary to apply various programs in the state, society, and educational institutions to avoid negative prejudices that lead to positive thinking and discrimination against the elderly.

A Study on Characteristics of Vegetation Distribution according to Revetment Techniques of Riverbank in Han River, Korea (한강 하천제방 호안공법에 따른 식생분포 특성 연구)

  • Kim, Won-Sik;Kwak, Jeong-In;Lee, Kyong-Jae;Han, Bong-Ho
    • Korean Journal of Environment and Ecology
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    • v.25 no.1
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    • pp.17-30
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    • 2011
  • This study has analyzed the vegetation composition in the areas using different slope revetment techniques of riverbanks, in a way to improve the vegetation induction in the future considering the ecological aspects of the induction in Garaeyoul Village, Gangdong-gu, Seoul. The result of the vegetation distribution in each different slope revetment technique was analyzed, that the naturalized herb was dominant in the pole block accounting for 70.7%, while native herb was dominant in the lawn block occupying 48.5% and in the crib block occupying 55.7%. The vegetation coverage measured by different slope revetment techniques was highest in the crib block(average 97.5%), followed by the lawn block(average 95.3%) and pole block(average 27.9%). The vegetation base area was the most wide in the crib block and the most narrowest in the pole block. The result of community analysis in areas using different slope revetment techniques, dry herbs and vine herbs were dominated and the coverage was very poor in the pole block. In the lawn block, the barb was fragmented into narrow areas due to the blocks, which prevented the creation of large-scale plant communities. In the crib block, Miscanthus sacchariflorus, Fescue arundinacea and Aster pilosus, which also consisted of large-scale communities. Average dry weight was also measured by each slope revetment technique. The weight was heaviest in the crib block with $187.63g/m^2$, followed by the lawn block($137.65g/m^2$) and pole block($6.75g/m^2$). The soil moisture contents in the crib block and lawn block was 16.3% and 15.2%, respectively, while that of the pole block was 4.7%, which revealed the highly dry condition of the pole block soil. The analysis result of soil chemical property showed that there was little difference in soil texture, soile acidity(pH), and exchangeable ion content, however, the soil organic matter(OM) content and available $P_2O_5$ were highest in the pole block. In the future, in order to induce more vegetation into river banks and walls, a proper construction method should be applied so that the vegetation area can be expanded as much as possible, considering the safety of the banks.

A Comparative Study of Two Different Heel Lancet Devices for Blood Collection in Preterm Infants (미숙아에서 채혈을 위한 발뒤꿈치 천자시 두 종류 천자 기구의 비교)

  • Lim, Hyo-Bin;Rhu, Mi-Joo;Jung, Ji-Mi;Jeon, Ga-Won;Sin, Jong-Beom
    • Neonatal Medicine
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    • v.17 no.2
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    • pp.239-244
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    • 2010
  • Purpose: To evaluate two different heel lancet device in terms of pain response and success of the procedure in the preterm infants undergoing heel puncture. Methods: 100 preterm infants undergoing capillary blood gas analysis or capillary bilirubin monitoring underwent heel puncture, were randomly allocated to blood sampling from the heel with either a conventional manual lancet or an automatic incision device. Primary outcome measures included the Premature Infants Pain Profile (PIPP) score, total duration of procedure, number of heel puncture and number of bruise. The pain response was evaluated using PIPP score and the effectiveness was evaluated using three criteria: total duration of blood sampling, number of puncture, bruising of the heel or ankle. Statistical analysis was performed using the SPSS ver. 13.0 program. Difference between the groups were analysed with t test (continuous variables) and the Chi square test or Fisher test (categorical variables). Results: The mean PIPP score was 4.91 for the automatic lancet group compared with 5.84 for the conventional manual lancet group (P=0.0255).The number of pain scores above 7 during blood collection did not differ between two groups (P=0.2167). The procedure took less time to perform in the automatic lancet group (mean, 30.69 seconds) than in the conventional lancet group (mean, 48.92 seconds) (P<0.0001). Conclusion: This study demonstrated that the automatic lancet device causes less pain and a shorter procedure time than the conventional manual lancet in preterm infants undergoing heel puncture. On the basis of these results the automatic lancet device is very useful method for blood collection in preterm infants by heel puncture.

Wheel Balance Cancer Therapy in the Treatment of Metastatic Gastric Carcinoma : A Retrospective Analysis of 62 Patients (수레바퀴 암 치료법을 시행받은 진행성 위암환자 62명에 대한 후향적 코호트 분석)

  • Park, Jeong-Seok;Yoo, Hwa-Seung;Lee, Yeon-Weol;Cho, Jung-Hyo;Son, Chang-Gue;Cho, Chong-Kwan
    • The Journal of Internal Korean Medicine
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    • v.28 no.3
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    • pp.531-543
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    • 2007
  • Backgrounds : Gastric cancer is one of the most frequent causes of cancer-related deaths worldwide. Gastric cancer patients frequently exhibit distant metastasis at the time of diagnosis and at present, there is no standard regimen after operation or chemotherapy to prevent metastasis and recurrences. Aims : The objective of the study was to compare the overall survival and disease free survival in patients treated with wheel balance therapy (WBT) with patients treated with WBT alone or the combination of WBT and conventional therapy and see if there were any significant improvements in survival between the two groups. Setting & Design : East-West Cancer Center at Daejeon University: retrospective study. Materials & Methods : We retrospectively analyzed 62 patients with stage III (40 patients) and stage IV (22 patients) gastric cancer who have received operation or chemotherapy 2 months prior to beginning WBT. The patients followed the WBT protocol which includes herbal medicine such as PSM capsules, OnePlus syrup, or HAD capsules which prevent metastasis and recurrences. Overall survival and disease free survival were analyzed and the patients were treated for 89.55 weeks and 49.27 weeks (median value) for stages III and IV, respectively. Statistical analysis used : Overall survival and disease free survival were estimated using the Kaplan-Meier method and the WBT and combination treatment arms were compared using the log rank test. Results : For stage III, the 3 year overall survival was 78.5% and disease free survival was 78.3%. Metastasis and recurrence occurred in 13 of 40 patients (32.5%). For stage IV, the 2 year overall survival was 18.2% and disease free survival was also 18.2%. Metastasis and recurrence occurred in 19 of 22 patients (86.4%). No significant difference was found statistically between the WBT alone and combination treatment arms though the combination regimen showed superiority (overall survival p=0.5093, disease free survival p=0.5175). Conclusions : WBT yielded satisfactory results in prolonging survival and preventing metastasis and recurrence in gastric cancer patients. The major treatment unit of WBT is composed of herbal medications (HAD, PSM capsules, OnePlus syrup) and a randomized, prospective study should be carried out using only this treatment unit in the future.

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Evaluation of Nutritional Status among Primary School Children in Uganda: Comparison of Urban and Rural Areas (우간다 초등학생의 영양섭취 실태조사: 도심지역과 농촌지역의 비교)

  • Lee, Ji-Yeon;Park, Hye-Jung;Yu, Min;Hwang, Ha-Yeong;Sung, Jung-Rim;Kim, Hee-Seon
    • Korean Journal of Community Nutrition
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    • v.25 no.2
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    • pp.91-101
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    • 2020
  • Objectives: The aim of this study was to investigate dietary intakes and nutritional status among Uganda primary school children from two selected schools in urban and rural areas. Methods: Data were collected from 350 pupils (6-14 years) in Mpigi district, Uganda. All participants were offered a school lunch meal (usually maize porridge and boiled beans). Dietary survey was conducted in October 2016. Data for dietary intake levels were collected by the 24-hour recall method with trained school staffs. The data were converted into nutrient intakes using the CAN-Pro 5.0 Program and compared with KDRIs to evaluate the nutritional status of the subjects. Diet quality indexes such as nutrient density, nutrient adequacy ratio (NAR), mean adequacy ratio (MAR), and index of nutritional quality (INQ) and a diet diversity index such as diet diversity score (DDS) were calculated to evaluate nutritional status among subjects. Data were analyzed using SPSS statistical programs. Results: Results show that the intakes of most nutrients were significantly different by schools. The nutritional status of micro-nutrients was very low in both schools according to analysis of nutritional indexes such as NARs and INQs. Students from both schools should improve intakes of micro-nutrients related to child growth such as calcium, Vitamin B6, zinc and folate. According to the analysis of dietary diversity, there was difference in dietary patterns by schools presumably due to their locations. Conclusions: This suggests that current meals could not provide adequate nutrients for the subjects and urgent nutrition interventions for school food services are needed to improve their nutritional well-being. New foods supplements based on local cuisine are also needed to ensure dietary diversity and sustainable development plans.

Comparison between Traditional IPA and Revised IPA; The Suncheon Bay Wetland Reserve (전통적 IPA(Importance-Performance Analysis)와 수정된 IPA의 비교연구; 순천만 습지를 대상으로)

  • Kim, Bo-Mi;Lee, Dong-Kun
    • Journal of the Korean Institute of Landscape Architecture
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    • v.45 no.2
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    • pp.40-50
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    • 2017
  • Compared to the traditional format, the revised IPA is an effective method for selecting a management strategy as compared to the traditional IPA. Comparison between the traditional IPA and revised IPA with a management strategy has been, however, limited. Therefore, the difference between the traditional IPA and revised IPA was compared to select an effective management strategy in the Suncheon Bay Wetland Reserve. First of all, related papers were reviewed to select an appropriate revised IPA. It was found that Deng (2007)'s revised IPA was appropriate for quantifying service quality and a management strategy that affects the measurable satisfaction of visitors in the space. Second, the results of the traditional IPA were compared with the revised IPA in the Suncheon Bay Wetland Reserve and the management strategy of the revised IPA and the changes of management factors were discussed. It was found that some management factors deviated from the order of the quadrant "low priority for managers", "Concentrate management here", "Keep up the good work" were moved to the order of the quadrants "Concentrate management here", "low priority for managers" and "Possible overkill" in the revised IPA grid. The complexity as a management factor resulted in higher demand management than the traditional IPA, which moved from "low priority for managers" to "Concentrate management here". Management factors resulted in lower demand management than the traditional IPA moved from "Concentrate management here" to "low priority for managers"; these consisted of shade trees, exhibition exteriors, programs, and a guided tour. Also, management factors moved from "Keep up the good work" to "Possible overkill" consisted of relaxation facilities, glow of the setting sun, a hedge, and an exhibition interior. Over all, the revised IPA responded properly to changes in the measurable satisfaction of visitors to the Suncheon Bay Wetland Reserve. Therefore, a revised IPA should be provided for accurate and reliable guidelines when decision makers establish management strategies.

Development of Three-Dimensional Trajectory Model for Detecting Source Region of the Radioactive Materials Released into the Atmosphere (대기 누출 방사성물질 선원 위치 추적을 위한 3차원 궤적모델 개발)

  • Suh, Kyung-Suk;Park, Kihyun;Min, Byung-Il;Kim, Sora;Yang, Byung-Mo
    • Journal of Radiation Protection and Research
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    • v.41 no.1
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    • pp.31-39
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    • 2016
  • Background: It is necessary to consider the overall countermeasure for analysis of nuclear activities according to the increase of the nuclear facilities like nuclear power and reprocessing plants in the neighboring countries including China, Taiwan, North Korea, Japan and South Korea. South Korea and comprehensive nuclear-test-ban treaty organization (CTBTO) are now operating the monitoring instruments to detect radionuclides released into the air. It is important to estimate the origin of radionuclides measured using the detection technology as well as the monitoring analysis in aspects of investigation and security of the nuclear activities in neighboring countries. Materials and methods: A three-dimensional forward/backward trajectory model has been developed to estimate the origin of radionuclides for a covert nuclear activity. The developed trajectory model was composed of forward and backward modules to track the particle positions using finite difference method. Results and discussion: A three-dimensional trajectory model was validated using the measured data at Chernobyl accident. The calculated results showed a good agreement by using the high concentration measurements and the locations where was near a release point. The three-dimensional trajectory model had some uncertainty according to the release time, release height and time interval of the trajectory at each release points. An atmospheric dispersion model called long-range accident dose assessment system (LADAS), based on the fields of regards (FOR) technique, was applied to reduce the uncertainties of the trajectory model and to improve the detective technology for estimating the radioisotopes emission area. Conclusion: The detective technology developed in this study can evaluate in release area and origin for covert nuclear activities based on measured radioisotopes at monitoring stations, and it might play critical tool to improve the ability of the nuclear safety field.