• Title/Summary/Keyword: t-z method

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Decomposition and Nutrient Dynamics of Aquatic Macrophytes in Lake Paldang

  • Shin, Jin-Ho;Yang, Keum-Chul;Yeon, Myung-Hun;Shim, Jae-Kuk
    • Journal of Ecology and Environment
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    • v.30 no.3
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    • pp.231-236
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    • 2007
  • This study examined the decomposition of blades and culms of aquatic emergent plant species, Zizania latifolia, Phragmites communis and Typha angustata, and changes in nutrient contents during decomposition. Z. latifolia, P. communis and T. angustata were the most frequently occurring species in Lake Paldang of Han River, Korea. Experiments were carried out from July 27 to December 14, 2005 in Lake Paldang using the litter bag method. The remaining masses of blade litter of each species at the end of experimental period were 21.2% of initial dry weight in Z. latifolia, 32.5% in P. communis, and 44.7% in T. angustata. In addition, the remaining mass of culm was 22.6% of initial dry mass in Z. latifolia, 56.4% in P. communis, and 38.1% in T. angustata. During the litter decomposition period, P, K, Na, and Mg concentration decreased rapidly within 10 days, but Ca and Mg concentration declined slowly. K contents remained below 10% of initial values in all litter samples retrieved during decomposition, whereas Ca and Mg concentration remained above 40% and 50% during decomposition in all three species. Na, P and Mn contents in litter varied among species and plant parts. P concentration in culms of P. communis remained at about 60% of initial concentration throughout the study, but the remaining P content in culms of Z. latifolia was only 10% of the original value at the end of the study period. The Mn concentration in blades of P. communis increased about 15-fold relative to the initial content by the end of experiment.

A Case Study on the Design and Construction of the Pile Bent System (단일현장타설말뚝을 이용한 교량기초의 설계 및 시공 사례)

  • Cho, Sung-Han;Kim, Hyung-Wook;Kim, Zu-Cheol
    • Proceedings of the Korean Geotechical Society Conference
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    • 2010.09a
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    • pp.357-367
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    • 2010
  • In this study, several design and construction cases of the pile bent system for bridges were introduced. The lateral displacement of the pile bent system is larger than the displacement of pile cap system, due to the smaller bending stiffness and the longer unsupported length. So, the analysis of the lateral pile displacement is main factor for the design of pile bent system and superstructure. For the accurate estimation of the pile displacement, an iterative analysis method was developed. The superstructure was analyzed regarding the pile foundation as $6{\times}6$ spring and the substructure was analysed using non-linear load transfer curves (p-y, t-z, q-z curve). And, to verify this analysis method, the estimated displacements are compared with the results of lateral load test. This analysis method is expected to be a viable alternative approach for the design of bridge foundation hereafter.

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Assessment of Carbon Stock and Uptake by Estimation of Stem Taper Equation for Pinus densiflora in Korea (우리나라 소나무의 수간곡선식 추정에 의한 탄소저장량 및 흡수량 산정)

  • Kang, Jin-Taek;Son, Yeong-Mo;Jeon, Ju-Hyeon;Lee, Sun-Jeoung
    • Journal of Climate Change Research
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    • v.8 no.4
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    • pp.415-424
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    • 2017
  • This study was conducted to estimate carbon stocks of Pinus densiflora with drawing volume of trees in each tree height and DBH applying the suitable stem taper equation and tree specific carbon emission factors, using collected growth data from all over the country. Information on distribution area, tree age, tree number per hectare, tree volume and volume stocks were obtained from the $5^{th}$ National Forest Inventory (2006~2010) and Statistical yearbook of forest (2016), and method provided in IPCC GPG was applied to estimate carbon stock and uptake. Performance in predicting stem diameter at a specific point along a stem in Pinus densiflora by applying Kozak's model, $d=a_{1}DBH^{a_2}a_3^{DBH}X^{b_{1}Z^2+b_2ln(Z+0.001)+b_3\sqrt{Z}+b_4e^z+b_5(\frac{DBH}{H})}$, which is well known equation in stem taper estimation, was evaluated with validations statistics, Fitness Index, Bias and Standard Error of Bias. Consequently, Kozak's model turned out to be suitable in all validations statistics. Stem volume table of P. densiflora was derived by applying Kozak's model and carbon stock tables in each tree height and DBH were developed with country-specific carbon emission factors ($WD=0.445t/m^3$, BEF = 1.445, R = 0.255) of P. densiflora. As the results of analysis in carbon uptake for each province, the values were high with Gangwon-do $9.4tCO_2/ha/yr$, Gyeongsandnam-do and Gyeonggi-do $8.7tCO_2/ha/yr$, Chungcheongnam-do $7.9tCO_2/ha/yr$ and Gyeongsangbuk-do $7.8tCO_2/ha/yr$ in order, and Jeju-do was the lowest with $6.8tC/ha/yr$. Total carbon stocks of P. densiflora were 127,677 thousands tC which is 25.5% compared with total percentage of forest and carbon stock per hectare (ha) was $84.5tC/ha/yr$ and $7.8tCO_2/ha/yr$, respectively.

The Effects of a PMS Nutritional Education Program for College Students (PMS 영양교육 프로그램의 효과 측정 연구)

  • Kim, Hae-Won
    • Journal of Korean Academy of Nursing
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    • v.36 no.7
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    • pp.1164-1174
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    • 2006
  • Purpose: This study was conducted to identify the effects of a PMS nutritional education program for college nursing students. Method: Subjects consisted of nursing students(experimental group: 19, control group: 27). The experimental group participated in a PMS nutritional education program for 8 weeks (including group and individual involvement). Data was collected before and after the education, and measurement tools were premenstrual symptoms, PMS knowledge, and self health behavior. Results: After the intervention, the experimental group showed a significant increase in PMS knowledge(Z=6.32, p=.000) and self health behavior(t=3.00, p=.004) compared to the control group. After the intervention the experimental group showed a significant increase in PMS knowledge(Z=-4.64, p=.000) and self health behavior(t=-3.04, p=.005) than before the intervention. Conclusions: These results suggest that the short term effects of a PMS nutritional education program for nursing students was proven useful and the program should be applied to PMS nutrition education for PMS clients as well as health professionals.

Perspectives on the Quality Assurance of Ginseng Products in North America

  • Fitzloff, J.F.;Yat, P.;Lu, Z.Z.;Awng, D.V.C.;Arnason, J.T.;Breemen, R.B.van;Ha, T.ll;Blumenthal, M.;Fong, H.H.S.
    • Proceedings of the Ginseng society Conference
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    • 1998.06a
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    • pp.138-145
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    • 1998
  • A validated and reproducible HPLC method was developed for the profiling and quantitative analysis of ginsenosides in commercial products available in North America. Analysis of 280 Panax ginseng and Panax quinquefolius products showed profiles indicative of the presence of ginsenosides in the majority of these products. However, the quantitative contents of the products vary greatly, not only in products of different formulations, but also of products within each of the fromulations examined.

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Differences in advanced cardiac life support knowledge, confidence, satisfaction, and performance ability of paramedic students according to simulation education methods (시뮬레이션 교육방법에 따른 응급구조학과 학생들의 전문심장소생술 지식, 수행자신감 및 수행능력의 차이)

  • Kim, Hyun-Jun;Lee, Hyo-Cheol
    • The Korean Journal of Emergency Medical Services
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    • v.25 no.3
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    • pp.111-125
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    • 2021
  • Purpose: This study aimed to analyze the impact of rapid cycle deliberate practice (RCDP) simulation education on advanced cardiac life support knowledge, confidence, satisfaction, and performance ability among paramedic students, and provide basic data on the appropriate methods of educational instruction. Methods: The 48 subjects to be instructed were divided into the traditional simulation education group and the RCDP simulation education group. Six participants were randomly assigned to each group and pre-surveyed. They were then exposed to a lecture about advanced cardiac life support related theories for 60 min and post-surveyed through questionnaires with the same learning goals and scenarios. Results: The advanced cardiac life support knowledge (t=-4.813, p=.000) and performance ability (t=-2.903, p=.006) were significantly different between the traditional simulation education and RCDP simulation education groups The results also showed a significant difference in attach monitor (z=6.857, p=.009), analyze EKG rhythm (z=11.111, p=.001), and defibrillation (z=12.632, p=.000), indicating differences in performance capabilities between the two groups. Conclusion: To improve advanced cardiac life support knowledge, performance ability, and confidence in the paramedic students who receive RCDP simulation education, simulation education methods that are appropriate for the subjects being taught, and detailed learning goals and feedback are necessary.

Effects of Aectic Acid-Water Solvents on the Organic Acid pulping of Wood (아세트산(酸)-물 용매계(溶媒系)에 의한 목재(木材)의 유기산(有機酸) 증해효과(蒸解效果))

  • Lee, Sun-Ho;Jo, Byoung-Muk
    • Journal of Forest and Environmental Science
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    • v.9 no.1
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    • pp.67-80
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    • 1993
  • There are a lot of serious problums associated with conventional pulping processes, such as kraft and sulfite. In order to tackle these difficulties, organic acid pulping of Populus tomentiglandulosa T. Lee and Pinus densiflora S. et Z. have been investigated as on alternative method. The acetic acid cooking of Populus tomentiglandulosa T. Lee achieved good delignification with pulp yields of 55-65% under almost all cooking conditions. In the acetic acid cooking of Pinus densiflora S. et Z., it was not cooked at a low temperature. The strength properties of the acetic acid pulps from Pinus tomentiglandulosa T. Lee showed the optimum with 95% acetic acid concentration at $185^{\circ}C$ maximum cooking temperature for 0.5hr cooking time. The strength properties of the acetic acid pulps from Pinus densiflora S. et Z. displayed excellent tear strength in comparison with those of the other softwoods. In the process of acetic acid cooking, glucose has been removed a little, but other sugars have been eliminated. The elemental compositions and $C_9$ formulas of acetosolv lignins from Populus tomentiglandulosa T. Lee were 63.88% carbon, 5.45% hydrogen and 30.67% oxygen and $C_9H_{9.15}O_{3.24}$ The elemental compositions and $C_9$ formulas of acetosolv lignins from Pinus densiflora S. et Z. were 61.85% carbon, 6.14% hydrogen and 32.01% oxygen and $C_9H_{9.15}O_{3.50}$ The Wt. av. MWT's of the acetosolv lignins from Pinus tomentiglandulosa T. Lee and Pinus densiflora S. et Z. were 731 and 725.

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FIRST PRINCIPLE CALCULATIONS OF MCD SPECTRA FOR SANDWICHED Co(110) SYSTEMS

  • Hong, Soon-C.;Lee, Jae-Il;Wu, R.;Freeman, A.J.
    • Journal of the Korean Magnetics Society
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    • v.5 no.5
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    • pp.575-578
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    • 1995
  • X-ray magnetic-circular-dichroism (MCD) spectra, orbital ($$) and spin magnetic moments ($$) for Co(110) monolayers a free standing mode or sandwiched between Pd(Pd/1Co/Pd)and Cu layers (Cu/1Co/Cu) are calculated using the thin film full potential linearized augmented plane wave energy band method. In contrast to the double peak structure predicted for the Co(0001) surface, only a minor side peak is found in the MCD spectra for Cu/Co/Cu, while MCD spectra for the other systems show a single peak structure. The MCD sum rules originally derived from a single ion model are found in the band approach to be valid for the systems investigated. However, for the spin sum rule, the magnetic dipole term ($$) is not negligible and needs to be included.

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Kinematic Analysis of T-Stop Motion by Inline Skate Rolling Speed (인라인 스케이트 활주속력에 따른 T-Stop의 운동학적 분석)

  • Han, Je-Hee;Woo, Byung-Hoon;Kim, Jeong-Goo;Kim, Tae-Whan;Kim, Sung-Sup;Kim, Eui-Hwan
    • Korean Journal of Applied Biomechanics
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    • v.20 no.4
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    • pp.355-364
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    • 2010
  • The purpose of this study was to investigate the kinematical analysis of T-stop motion by inline skate rolling speed. Six subjects were participated in the experiment(age: $35.0{\pm}3.3$ yrs, weight: $72.70{\pm}5.1\;kg$, height: $176.30{\pm}3.1\;cm$, career: $10.00{\pm}2.5$ yrs). The study method adopted 3-dimensional analysis and 2 cameras for filming to analyze the required displacement of center of mass, displacement of right and left hip joint, displacement of right and left knee joint, displacement of trunk tilt using by APAS. The results were as follows; In anterior-posterior displacement of COM, the faster rolling speed, the longer displacement at phase 2. In vertical displacement of COM, the faster rolling speed, the lower displacement. In medial-lateral displacement of COM, there was no significant on rolling speed. In angular displacement of right thigh segment, the faster rolling speed, the bigger displacement in X and Z axis. In angular displacement of left thigh segment, the faster rolling speed, the lower displacement in X axis. In angular displacement of right shank segment, the faster rolling speed, the bigger displacement in Z axis. In angular displacement of left shank segment, the faster rolling speed, the bigger displacement in X and Y axis. In angular displacement of trunk segment, the faster rolling speed, the bigger displacement in Z axis.