• Title/Summary/Keyword: Element analysis

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A Study on Estimating Shear Strength of Continuum Rock Slope (연속체 암반비탈면의 강도정수 산정 연구)

  • Kim, Hyung-Min;Lee, Su-gon;Lee, Byok-Kyu;Woo, Jae-Gyung;Hur, Ik;Lee, Jun-Ki
    • Journal of the Korean Geotechnical Society
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    • v.35 no.5
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    • pp.5-19
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    • 2019
  • Considering the natural phenomenon in which steep slopes ($65^{\circ}{\sim}85^{\circ}$) consisting of rock mass remain stable for decades, slopes steeper than 1:0.5 (the standard of slope angle for blast rock) may be applied in geotechnical conditions which are similar to those above at the design and initial construction stages. In the process of analysing the stability of a good to fair continuum rock slope that can be designed as a steep slope, a general method of estimating rock mass strength properties from design practice perspective was required. Practical and genealized engineering methods of determining the properties of a rock mass are important for a good continuum rock slope that can be designed as a steep slope. The Genealized Hoek-Brown (H-B) failure criterion and GSI (Geological Strength Index), which were revised and supplemented by Hoek et al. (2002), were assessed as rock mass characterization systems fully taking into account the effects of discontinuities, and were widely utilized as a method for calculating equivalent Mohr-Coulomb shear strength (balancing the areas) according to stress changes. The concept of calculating equivalent M-C shear strength according to the change of confining stress range was proposed, and on a slope, the equivalent shear strength changes sensitively with changes in the maximum confining stress (${{\sigma}^{\prime}}_{3max}$ or normal stress), making it difficult to use it in practical design. In this study, the method of estimating the strength properties (an iso-angle division method) that can be applied universally within the maximum confining stress range for a good to fair continuum rock mass slope is proposed by applying the H-B failure criterion. In order to assess the validity and applicability of the proposed method of estimating the shear strength (A), the rock slope, which is a study object, was selected as the type of rock (igneous, metamorphic, sedimentary) on the steep slope near the existing working design site. It is compared and analyzed with the equivalent M-C shear strength (balancing the areas) proposed by Hoek. The equivalent M-C shear strength of the balancing the areas method and iso-angle division method was estimated using the RocLab program (geotechnical properties calculation software based on the H-B failure criterion (2002)) by using the basic data of the laboratory rock triaxial compression test at the existing working design site and the face mapping of discontinuities on the rock slope of study area. The calculated equivalent M-C shear strength of the balancing the areas method was interlinked to show very large or small cohesion and internal friction angles (generally, greater than $45^{\circ}$). The equivalent M-C shear strength of the iso-angle division is in-between the equivalent M-C shear properties of the balancing the areas, and the internal friction angles show a range of $30^{\circ}$ to $42^{\circ}$. We compared and analyzed the shear strength (A) of the iso-angle division method at the study area with the shear strength (B) of the existing working design site with similar or the same grade RMR each other. The application of the proposed iso-angle division method was indirectly evaluated through the results of the stability analysis (limit equilibrium analysis and finite element analysis) applied with these the strength properties. The difference between A and B of the shear strength is about 10%. LEM results (in wet condition) showed that Fs (A) = 14.08~58.22 (average 32.9) and Fs (B) = 18.39~60.04 (average 32.2), which were similar in accordance with the same rock types. As a result of FEM, displacement (A) = 0.13~0.65 mm (average 0.27 mm) and displacement (B) = 0.14~1.07 mm (average 0.37 mm). Using the GSI and Hoek-Brown failure criterion, the significant result could be identified in the application evaluation. Therefore, the strength properties of rock mass estimated by the iso-angle division method could be applied with practical shear strength.

Musical Analysis of Jindo Dasiraegi music for the Scene of Performing Arts Contents (연희현장에서의 올바른 활용을 위한 진도다시래기 음악분석)

  • Han, Seung Seok;Nam, Cho Long
    • (The) Research of the performance art and culture
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    • no.25
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    • pp.253-289
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    • 2012
  • Dasiraegi is a traditional funeral rite performance of Jindo located in the South Jeolla Province of South Korea. With its unique stylistic structure including various dances, songs and witty dialogues, and a storyline depicting the birth of a new life in the wake of death, embodying the Buddhism belief that life and death is interconnected; it attracted great interest from performance organizers and performers who were desperately seeking new contents that can be put on stage as a performance. It is needless to say previous research on Dasiraegi had been most valuable in its recreation as it analyzed the performance from a wide range of perspectives. Despite its contributions, the previous researches were mainly academic focusing on: the symbolic meanings of the performance, basic introduction to the components of the performance such as script, lyrics, witty dialogue, appearance (costume and make-up), stage properties, rhythm, dance and etc., lacking accurate representation of the most crucial element of the performance which is sori (song). For this reason, the study analyzes the music of Dasiraegi and presents its musical characteristics along with its scores to provide practical support for performers who are active in the field. Out of all the numbers in Dasiraegi, this study analyzed all of Geosa-nori and Sadang-nori, the funeral dirge (mourning chant) sung as the performers come on stage and Gasangjae-nori, because among the five proceedings of the funeral rite they were the most commonly performed. There are a plethora of performance recordings to choose from, however, this study chose Jindo Dasiraegi, an album released by E&E Media. The album offers high quality recordings of performances, but more importantly, it is easy to obtain and utilize for performers who want to learn the Dasiraegi based on the script provided in this study. The musical analysis discovered a number of interesting findings. Firstly, most of the songs in Dasiraegi use a typical Yukjabaegi-tori which applies the Mi scale frequently containing cut-off (breaking) sounds. Although, Southern Kyoung-tori which applies the Sol scale was used, it was only in limited parts and was musically incomplete. Secondly, there was no musical affinity between Ssitgim-gut and Dasiraegi albeit both are for funeral rites. The fundamental difference in character and function of Ssitgim-gut and Dasiraegi may be the reason behind this lack of affinity, as Ssitgim-gut is sung to guide the deceased to heaven by comforting him/her, whereas, Dasiaregi is sung to reinvigorate the lives of the living. Lastly, traces of musical grammar found in Pansori are present in the earlier part of Dasiraegi. This may be attributed to the master artist (Designee of Important Intangible Cultural Heritage), who was instrumental in the restoration and hand-down of Dasiaregi, and his experience in a Changgeuk company. The performer's experience with Changgeuk may have induced the alterations in Dasiraegi, causing it to deviate from its original form. On the other hand, it expanded the performative bais by enhancing the performance aspect of Dasiraegi allowing it to be utilized as contents for Performing Arts. It would be meaningful to see this study utilized to benefit future performance artists, taking Dasiraegi as their inspiration, which overcomes the loss of death and invigorates the vibrancy of life.

Interpretation of the Meaning of Korean Traditional Colors Symbol Found out in Soswaewon (소쇄원에 나타나는 전통 색채 분석과 의미 해석)

  • Han, Hee-Jeong;Cho, Se-Hwan
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.32 no.1
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    • pp.63-73
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    • 2014
  • This study was intended to analyze the correlation between the builder's intentions and the colors that are revealed through the analysis of the manifestation of symbolic colors as the signs and symbols that are shown in the traditional space of Soshaewon as one of the representative retreating villa gardens of Chosun Dynasty and the interpretation of the meanings. The research on the traditional colors and the intended background of Soshaewon and so on was conducted by examining the relative literature and the contents as the objects for the empirical analysis were the scenic beauties and spatial elemnts that are shown in the plan of Soshewon and the poems about Soshewon 48 scenes as well as the contents of the poems related to Five Primary Colors that are used based on "the Ideology of Five Elements of the Positive and Negative". Espectially, this study was conducted by dividing the spatial elements shown in Soswaewon broadly into the visual, synesthetic and symbolic & cognitive spaces in order to classify the locations and directions of the spaces and natural objects as the visual space, the seasons, the points of times and the five sensory organs as the synesthetic space and the "Four Moral Begginings" & the "Seven Emotions" of New Confucianism as the symbolic and cognitive space and by analyzing if there are any correlation between the decided intentions and the spatial meanings that are revealed by analyzing the system of five primary colors which are used in each spatial element.7) As a result from the analysis of the colors that are used based on the three spatial components of Soshaewon, it was found that one of Five Primary Colors were used 74 times in total. First, in the visual spatial component, one of the colors was used 18 times in total including 2 times of blue, 1 time of red, 6 times of yellow, 4 times of white and 5 times of black. The fact that yellow symbolizing the source of everything and white symoblizing cleanness and pureness are used relatively more often than blue and red symbolizing nature and life respectively can be interpreted that the builder, Mr. San-bo Yang's intention to build Soshaewon is related to the meaning symbolizing the pure will of the builder who wanted to seclude himself from society rather than to give priority to enjoying nature. Second, in the synesthetic spatial component which are selected from the 48 scenes of Soshaewon, one of Five Primary Colors was used 38 times in total including 11 times of blue, 8 times of red, 4 times of yellow, 5 times of white and 10 times of black. Since blue and red symbolizing nature and life respectively are used more often than yellow and black symbolizing the source of the world and pureness & knowledge respectively, it was interpreted that the builder means to be faithful to the unique basic functions of the retreating villa with which the builder wanted to enjoy his passion for enjoying nature and exploring knowledge even though the builder built the villa garden for the purpose of keeping himself pure while being unstained by the world. Finally, it was analyzed that one of Five Primary Colors was used 18 times in total including 4 times of blue, 5 times of red and 9 times of white in the symbolic and cognitive spatial components of the 48 scenes. Since it was found that white symbolizing the builder's political pureness is used at the same frequency as blue and red symbolizing nature and life respectively are used as a result from the analysis, it was interpreted that the intention of creating Soshaewon was emotionally revealed at the same percentage in the aspects of his political pureness and enjoyment of nature through his poems. Especially, as a result from such 3 kinds of analyses regarding to the frequency of using Five Primary Colors, it was found that the number of times using Five Primary Colors in the synesthetic spatial component was 38 as the highest percentage, around 51% followed by each 18 times as the24.5% respectively in the visual and cognitive & symbolic spatial spaces. Based on such results, it can be interpreted that the builder, Mr. San-bo Yang's intention of creating Soshaewon sympolizes that his intention for enjoying the basic nature and the vitality of nature within the retreating villa garden is hidden at the same proportion as his intention for keeping himself pure from the unrightful world. It was intended to reveal the traditional colors which are hidden in a traditional retreating villa by analyzing the correlation between the symbolic meanings and the spatial components of Soshaewon based on the Five Primary Colors which are originated from the "Ideology of the Five Natural Elements of the Positive and Negative", but it is thought that it is possible to explore whether such a theory can be generally applied to other kinds of retreating villa gardens or not through a study on other retreating villa gardens as other examples in which the builder's apparent pure intentions, such as enjoyment of nature and persuit of study, etc., unlike Soshaewon are hidden.

The Recognition about Food Wastes Treatment at Yongin Area

  • Kim, Jeong-Hyun;Kang, Hee-Joo;Kim, Kyung-Tae;Kim, Hyun-Soo;Hwang, Seong-Hee;Kim, Yong-Chul;Kim, Pan-Gyi
    • Journal of Environmental Health Sciences
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    • v.30 no.4
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    • pp.329-343
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    • 2004
  • We conducted to investigate citizen's attitude to the treatment of food waste in Yongin city. The respondent of $41.81\%$ throws the food waste eliminate from home and store less than 1l in Yongin. When they dump the food waste, they speak out the inconvenience of damaged envelope by animals in case of home and store. This caused troubles for reason of sanitary. So a local autonomous entity must carefully consider of expand use specially designed container as like apartment house. They give an answer that the collecting time of food waste is suitable form dawn till morning. This answer shows the satisfaction of the period time to collect the food waste. They prefer to be appointed the exclusive place to collect food waste. The service interval of collect is suitable 1 time a day. They want to increase the number of washing of the collecting container. This is good method for sanitary condition, but the care of the period time to collect the food waste is more efficient than the care of the number of washing the collecting container. The care of the period time minimizes to incur the enmity of the people and to pollute in environment. The major of respondent handled the food waste after keeping the basket or a kit. This fact shows to us almost citizen doesn't feel the seriousness to remove the moisture of the food waste. Recently, many solutions which can be disposal efficiently are getting magnified and improved owing to increase utilities channel to loss in quantities and dry the food waste. We expect the reduction of food waste is solved getting easily step by step. The results of the awareness about the facility of food waste show citizen prefer recycling facility to the other facilities. If recycle facility and incineration facility are constructed, they were worried about bed smell. When some facility of the food waste is constructed, they have to maintain and to handle not to incur the enmity of the people. The spread rate of specially designed container already increased, the citizen set a high value on the use of specially designed container more than amount-rate vinyl envelope that people have used for several years. In the cost treatment about food waste, the major respondent answered the use cost of specially designed container is suitable price. So we can know the use charge is proper level. The majority of citizen more prefer autonomous plan which voluntary atmosphere creation and public information by mass media than levy system and rising treatment cost which forced plan. The citizens have pretty positive thinking of incineration, so the government needs more efforts for a public notice, which includes the incineration is no more than abandoned thing. Each of local self government has to sort the food waste and make kind of resource system related to collecting and carrying, constructing a suitable facility, proper disposal of the food waste and producing harmless in our surrounding in order to solve the invisible problems. To do above mentioned things, we have to analyze referred several problems till now. Also, to minimize the side effect, the government will have to improve through enforce the system.

Characteristics of Radon Variability in Soils at Busan Area (부산광역시 일대의 토양 내 라돈 농도 변화 특성)

  • Kim, Jin-Seop;Kim, Sun-Woong;Lee, Hyo-Min;Choi, Jeong-Yun;Moon, Ki-Hoon
    • Economic and Environmental Geology
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    • v.45 no.3
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    • pp.277-294
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    • 2012
  • The characteristics of temporal spacial radon variation in soil according to parent rock type and affecting factors were studied in Busan, Korea. The concentration of $^{222}Rn$ in soils and their parent elements ($^{226}Ra$,$^{228}Ra$, U and Th) in rocks and soils were measured at 24 sites in Busan area. The distribution and transportation behavior of these parent elements were analyzed and their correlations to radon concentration in soil were determined. Topographic effects were also evaluated. Two in-situ radon measurement (soil probe and buried tube) methods were applied to measure radon concentration in soil and their accuracies were evaluated. The spatial variation of radon in soil generally reflected U concentration in the parent rock. Average radon concentrations were higher in plutonic rocks than in volcanic rocks and were decreased in the order of felsic>intermediate>mafic rock. However, the radon concentrations were significantly varied in soils developed from same parent rocks due to the disequilibrium of U and $^{226}Ra$ between rock and soil. As results, the correlation of these element concentrations between rocks and soils was very low and radon concentrations in soils had highly co-related to the concentrations of these elements in soils. Th and $^{228}Ra$ show complex enrichment characteristics, differing significantly with U, in soils developed from same parent rock because the geochemical behavior of these elements during weathering and soil developing process was different with U. The radon concentrations in the same depth of soil in slope area were also different according to positions. The radon concentrations in soils developed from same parent rocks (19 sites at Pusan National University) varied 6.8~29.8Bq/L range because of small scale topographic variation. The opposite seasonal variation pattern of radon were observed according to soil properties. It was determined that buried tube method is more accurate method than soil probe method and was very advantageous application for the analysis for the characteristics of temporal spacial radon variation in soil.

Geochemical Characteristics and Pollution Level of Heavy Metals of Asian Dust in Daejeon Area, 2007 (spring season) (2007년 봄철 대전지역에서 발생한 황사 및 대기부유물의 지구화학적 특성 및 중 금속의 오염도)

  • Lee, Pyeong-Koo;Youm, Seung-Jun;Bae, Beob-Geun
    • Economic and Environmental Geology
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    • v.45 no.3
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    • pp.217-235
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    • 2012
  • We evaluated the geochemical characteristics and their potential pollution of Asian Dusts in Daejeon, Korea during spring 2007. Compared with the chemical compositions of soils in source area of Asian Dust, those of aerosols in Daejeon were enriched with trace elements (ten to hundred fold), inferring that pollutants from China have affected on local environment in adjoining country such as Korea. Chemical analysis of aerosols during Asian dust showed that fine particles ($PM_{2.5}$) contained high contents of trace elements such as Cr, Cu, Pb, Zn, V, S, As, Cd, Co, Ni, Mo, Sb, Cs, Rb, Th, Sc and Y. In the case of TSP (Total Suspended Particle), Zr, Sr, Ba, Li, Th and U were contained much more than other trace elements. The contents of some elements (i.e. Li, Cs, Co, U, Cr, Ni, Rb, V, Th, Y, Sr and Sc) in aerosols collected in Asian Dust period, which are not likely enriched by air pollutants, were higher (2 - 4.2 fold) than those in Non Asian Dust period, indicating that these elements could be used as indicator elements for determining the occurrence of Asian Dust phenomena (especially, Sr, V, Cr & Li). In the case of Asian Dust coming through the big cities and/or industrial areas of China, the domestic aerosols had higher contents of trace elements (such as S, Cd, Zn, Pb, Cu, Mo and As) than those from Northeastern China via North Korea, indicating that the transportation courses of air mass are very important to determine the pollution degrees. Using the enrichment factors of trace elements in aerosols during Asian Dust and Non Asian Dust, we identified that some elements (i.e. S, Zn, Cu, Pb, As, Mo and Cd) were most problematic in terms of environmental hazard aspects, and these elements could affect adverse effects on human health as well as ecosystem and surface environment (soil and water) through long-lived precipitation.

Genesis and Characteristics of the Soil Clay Minerals Derived from Major Parent Rocks in Korea II. Physical and Chemical Properties of the Whole Soils (한국(韓國)의 주요(主要) 모암(母岩)에서 발달(發達)된 토양점토광물(土壤粘土鑛物)의 특성(特性)과 생성학적(生成學的) 연구(硏究) II. 토양(土壤)의 이화학적(理化學的) 특성(特性))

  • Um, Myung-Ho;Kim, Tai-Soon
    • Korean Journal of Soil Science and Fertilizer
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    • v.24 no.2
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    • pp.79-85
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    • 1991
  • This study reports on the physical and chemical properties of the whole soils (<2mm) derived from five major rocks of granite, granite-gneiss, limestone, shale, and basalt in Korea. The properties were considered from the kind and frequency distribution of rock-forming minerals in the parent rocks. In particle size distribution, sand fractions were high in the soils from granite-gneiss, silt fractions mainly, in the residual soils from limestone, shale, and basalt. And clay fractions were particularly high in the colluvial soil from limestone and the old alluvial soil from basalt. pH, extractable Ca and Mg, and cation exchange capacity of the soils derived from limestone might be considered to be high due to the presence of sand and/or silt-sized calcite and dolomite inherited from the parent rocks. However, the soils derived from granite and granite-gneiss, being abundant in feldspars, quartz, and micas, showed a tendency to the contrary. A soil from shale composing of high quartz tended to have pH. extractable Ca, base saturation, and low exchangeable Al. In total element analysis, the soils derived from parent rocks with high contents of (i) orthoclase and micas, (ii) biotite, primary chlorite, and augite, and (iii) carbonate minerals and plagioclase as a rock-forming mineral showed a tendency to decrease the contents of $K_2O$, $Fe_2O_3$ and MgO, and CaO in comparison with those of their parent rocks.

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Structural Analysis of Concrete-filled FRP Tube Dowel Bar for Jointed Concrete Pavements (콘크리트 포장에서 FRP 튜브 다웰바의 역학적 특성 분석)

  • Park, Jun-Young;Lee, Jae-Hoon;Sohn, Dueck-Su
    • International Journal of Highway Engineering
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    • v.13 no.3
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    • pp.21-30
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    • 2011
  • As well known, dowel bars are used to transfer traffic load acting on one edge to another edge of concrete slab in concrete pavement system. The dowel bars widely used in South Korea are round shape steel bar and they shows satisfactory performance under bending stress which is developed by repetitive traffic loading and environment loading. However, they are not invulnerable to erosion that may be caused by moisture from masonry joint or bottom of the pavement system. Especially, the erosion could rapidly progress with saline to prevent frost of snow in winter time. The problem under this circumstance is that the erosion not only drops strength of the steel dower bar but also comes with volume expansion of the steel dowel bar which can reduce load transferring efficiency of the steel dowel bar. To avoid this erosion problem in reasonable expenses, dowers bars with various materials are being developed. Fiber reinforced plastic(FRP) dower that is presented in this paper is suggested as an alternative of the steel dowel bar and it shows competitive resistance against erosion and tensile stress. The FRP dowel bar is developed in tube shape and is filled with high strength no shrinkage. Several slab thickness designs with the FRP dowel bars are performed by evaluating bearing stress between the dowel bar and concrete slab. To calculated the bearing stresses, theoretical formulation and finite element method(FEM) are utilized with material properties measured from laboratory tests. The results show that both FRP tube dowel bars with diameters of 32mm and 40mm satisfy bearing stress requirement for dowel bars. Also, with consideration that lean concrete is typical material to support concrete slab in South Korea, which means low load transfer efficiency and, therefore, low bearing stress, the FRP tube dowel bar can be used as a replacement of round shape steel bar.

Analysis of Contributing Factor for Cation Ratio to Calcium in Nutrient Solution on the Incidence of Blossom-end Rot in Sweet Pepper 'RZ208' Grown in Hydroponics (파프리카 배꼽썩음과 발생에 미치는 배양액 내 칼슘에 대한 양이온 기여인자 분석)

  • Lee, Hye-Jin;Oh, Jeong-Sim;Choi, Ki-Young;Lee, Yong-Beom;Bae, Jong-Hyang;Rhee, Han-Cheol;Kim, Dong-Eok
    • Horticultural Science & Technology
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    • v.30 no.1
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    • pp.27-33
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    • 2012
  • This study aimed to investigate the responses of plant growth and blossom-end rot (BER) incidence to calcium (Ca) and its three kinds of antagonistic cations (K, Mg, and $NH_4$-N) with various ratios in nutrient solution for sweet paper (Capsicum annuum L. 'RZ208'). Both Ca to each cation and Ca to a series of cation combinations, such as potassium (K), ammonium nitrate ($NH_4$), or magnesium (Mg) were more influential to the fruit growth and quality than plant growth. Especially, the BER incidence was significantly influenced by the ratio treatments. For examples, when Ca:(K + Mg) or Ca:(K + Mg + $NH_4$) ratio was 1:2 the highest incident rate of BER about 70.3 or 86.3% was observed, lowering the marketable yield to 19 or 13.7% of the total yield, respectively. The correlation coefficiencies (= r) to relationships between the BER and K as well as BER and $NH_4$ were 0.82 (P < 0.05) and 0.65 (P < 0.05), respectively. Combination only with the Mg element was not correlated with the BER incidence. However, when both of the K and Mg concentrations were 0.65 (P < 0.05). The highest correlation coefficiency, 0.92 (P < 0.05), was found to a relationship between the BER and the tree elemental combination.

Effect of the Dental Hygienics Students' $2{\times}2$ Achievement Target Orientation on the Self-Regulated Learning (치위생과 학생의 $2{\times}2$ 성취목표지향성이 자기조절학습에 미치는 영향)

  • Jung, Gi-Ok;Choi, Gyu-Yil
    • Journal of dental hygiene science
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    • v.12 no.4
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    • pp.375-382
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    • 2012
  • This research will target the Dental Hygienics students to identify the level and type of the $2{\times}2$ achievement target orientation, and will study how this achievement target orientation is related to the Self-Regulated Learning, as well as the effect on the each sub elements of the Self-Regulated Learning (SRL). Among the $2{\times}2$ achievement target orientation of all the female university students, the skillful approach was found to be highest. In case of the adjustment of the motivation following grade, intrinsic value of the 1st grader was higher than the intrinsic value of the 2nd and 3rd graders. As for the behavior adjustment, the 3rd grader's time and studying adjustment were found to be higher. Mean while, pursuit of the cooperation was found to be high compared to the time and studying adjustment of the1st and 2nd graders. Second, intrinsic value, overt goal orientation, and studying environment adjustment among the SRL's subelements, manifested significant correlation with all the sub elements of the $2{\times}2$ achievement target orientation. As for the elements that affected cognition adjustment, grade and skillful approach were found to exert significant effect on the performance adjustment. As for the element that affects behavior adjustment, grade and skillful approach exerted significant effect on the sub elements of the behavior adjustment. Analysis on the effect of the achievement target orientation and SRL implies that the direction of the students' learning goal can be modified and that they can learn effectively by using the SRL appropriately. When the two elements are factored in carefully, the key findings could serve as a base data that can motivate the students, inducing effective learning process.