• Title/Summary/Keyword: F.E.Model

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A Review on Ultimate Lateral Capacity Prediction of Rigid Drilled Shafts Installed in Sand (사질토에 설치된 강성현장타설말뚝의 극한수평지지력 예측에 관한 재고)

  • Cho Nam Jun;Kulhawy F.H
    • Journal of the Korean Geotechnical Society
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    • v.21 no.2
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    • pp.113-120
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    • 2005
  • An understanding of soil-structure interaction is the key to rational and economical design for laterally loaded drilled shafts. It is very difficult to formulate the ultimate lateral capacity into a general equation because of the inherent soil nonlincarity, nonhomogeneity, and complexity enhanced by the three dimensional and asymmetric nature of the problem though extensive research works on the behavior of deep foundations subjected to lateral loads have been conducted for several decades. This study reviews the four most well known methods (i.e., Reese, Broms, Hansen, and Davidson) among many design methods according to the specific site conditions, the drilled shaft geometric characteristics (D/B ratios), and the loading conditions. And the hyperbolic lateral capacities (H$_h$) interpreted by the hyperbolic transformation of the load-displacement curves obtained from model tests carried out as a part of this research have been compared with the ultimate lateral capacities (Hu) predicted by the four methods. The H$_u$ / H$_h$ ratios from Reese's and Hansen's methods are 0.966 and 1.015, respectively, which shows both the two methods yield results very close to the test results. Whereas the H$_u$ predicted by Davidson's method is larger than H$_h$ by about $30\%$, the C.0.V. of the predicted lateral capacities by Davidson is the smallest among the four. Broms' method, the simplest among the few methods, gives H$_u$ / H$_h$ : 0.896, which estimates the ultimate lateral capacity smaller than the others because some other resisting sources against lateral loading are neglected in this method. But it results in one of the most reliable methods with the smallest S.D. in predicting the ultimate lateral capacity. Conclusively, none of the four can be superior to the others in a sense of the accuracy of predicting the ultimate lateral capacity. Also, regardless of how sophisticated or complicated the calculating procedures are, the reliability in the lateral capacity predictions seems to be a different issue.

Study on the Treesize Prediction Model : A case study of Zelkova serrata, Pinus strobus and Magnolia denudata (주요조경수목의 크기 예측 " 모델 "에 관한 연구 : 느티나무, 스트로브잣나무, 백목련을 대상으로)

  • 김남춘;최준수;문석기
    • Journal of the Korean Institute of Landscape Architecture
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    • v.16 no.1
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    • pp.27-35
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    • 1988
  • Size characteristics of three widely used landscape trees were analized to establish a methodology of size prediction as time Passes. Tree height, tree width, stem diameter(breast or surface), canopy length and tree age were measured directly and indirectly(by using photograph), and the data were analized by using regression analysis through PC-SAS. The results are summarized as follows : 1. Zelkova serrata MAKINO showed relatively slow growth rate and the tree form was changed as aged. Size predictions were available by using the regression equations listed below : Surface diameter = 0.8293 x AGE Tree height = 0.4109(0.8293 x AGE) - 0.0039(0.7273 x AGE)$^2$Tree width = 0.3240(0.8293 x AGE) - 0.0024(0.1293 x AGE)$^2$Canopy length = 0.1337(0.8293 x AGE) - 0.0020(0.7293 x AGE)$^2$2. Pinus strobus L. showed relatively fast growth rate and the tree form did not change much as aged. Size predictions were available by using the regression equations listed below. Breast diameter = 0.756 x AGE Tree height = 0.7695(0.756 x AGE) - 0.0164(0.75\ulcorner x AGE)$^2$Tree width = 0.4331(0.756 x AGE) - 0.0079(0.75\ulcorner x AGE)$^2$Canopy length = 0.1365(0.756 x AGE) - 0.0032(0.75f x AGE)$^2$ 3. In case of Magnolia denudata DESROUX, tree form was determined relatively earlier than the other two species. Si2e predictions were available by using the regression equations listed below : Surface diameter = 0.88 x AGE Tree height = 0.5412(0.88 x AGE) - 0.0110(0.88 x AGE)$^2$ Tree width = 0.3752(0.88 x AGE) - 7.0061(0.88 x AGE)$^2$Canopy length = 0.1110(0.88 x AGE) - 0.0022(0.88 x AGE)$^2$ This study aimed to find a way to predict size change of landscaping plants. This methodology will be applied to a wide range of landscape plants to provide practical data to landscape designers.

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Development of an Appropriate Deposit-Estimation System for Restoration of Land-Use-Changed Forest Lands Using the Delphi Technique (델파이 기법을 활용한 적정 산지복구비 산출체계의 개발)

  • Koo, Kiwoon;Kweon, Hyeongkeun;Lee, Sang In;Kwon, Semyung;Seo, Jung Il
    • Journal of Korean Society of Forest Science
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    • v.110 no.4
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    • pp.630-647
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    • 2021
  • We determined the current problem of the restoration deposit-estimation system, stipulated by the Mountainous Districts Management Act, using the Delphi technique. Consequently, we proposed a standard model for forest land restoration to derive a reasonable deposit-estimation system. With the result of the Delphi survey, the inappropriateness of land-use type and slope gradient classifications was shown; the insufficiency of standard works was a significant problem in the current system. A way to solve these problems was devised, to reorganize the current land-use type into the subject of the site. The specific subjects included the following: (i) to permit or report forest land-use change and temporary use of forest land, (ii) to report temporary use of forest land, (iii) to permit stone collection or sale for mineral mining, and (iv) to allow sediment collection. The current slope gradient subdivision into (a) θ<10°, (b) 10°≦θ<15°, (c) 15°≦θ<20°, (d) 20°≦θ<25°, (e) 25°≦θ<30°, and (f) θ≧30° and the reorganization of 17 standard works into 22 standard works were deemed as solutions, along with seven additional works. We developed 24 standard models for the forest land restoration project based on the aforementioned results. The deposits estimated by these models ranged from 34,185,000 (Korean) won to 607,403,000 won. If additional works, premiums, discounts, and supervision fees are added to the models, the deposit increases to an estimated 668,143,000 won subject to permission for stone collection or sale and mineral mining. Experts agree on the distribution of the restoration deposits estimated by these models at a high level in the Delphi survey. Our findings are expected to contribute to securing the appropriateness of the restoration cost deposited for the smooth performance of the vicariously executed restoration project.

Forecasting Leaf Mold and Gray Leaf Spot Incidence in Tomato and Fungicide Spray Scheduling (토마토 재배에서 점무늬병 및 잎곰팡이병 발생 예측 및 방제력 연구)

  • Lee, Mun Haeng
    • Journal of Bio-Environment Control
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    • v.31 no.4
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    • pp.376-383
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    • 2022
  • The current study, which consisted of two independent studies (laboratory and greenhouse), was carried out to project the hypothesis fungi-spray scheduling for leaf mold and gray leaf spot in tomato, as well as to evaluate the effect of temperature and leaf wet duration on the effectiveness of different fungicides against these diseases. In the first experiment, tomato leaves were infected with 1 × 104 conidia·mL-1 and put in a dew chamber for 0 to 18 hours at 10 to 25℃ (Fulvia fulva) and 10 to 30℃ (Stemphylium lycopersici). In farm study, tomato plants were treated for 240 hours with diluted (1,000 times) 30% trimidazole, 50% polyoxin B, and 40% iminoctadine tris (Belkut) for protection of leaf mold, and 10% etridiazole + 55% thiophanate-methyl (Gajiran), and 15% tribasic copper sulfate (Sebinna) for protection of gray leaf spot. In laboratory test, leaf condensation on the leaves of tomato plants were emerged after 9 hrs. of incubation. In conclusion, the incidence degree of leaf mold and gray leaf spot disease on tomato plants shows that it is very closely related to formation of leaf condensation, therefore the incidence of leaf mold was greater at 20 and 15℃, while 25 and 20℃ enhanced the incidence of gray leaf spot. The incidence of leaf mold and gray leaf spot developed 20 days after inoculation, and the latency period was estimated to be 14-15 days. Trihumin fungicide had the maximum effectiveness up to 168 hours of fungicides at 12 hours of wet duration in leaf mold, whereas Gajiran fungicide had the highest control (93%) against gray leaf spot up to 144 hours. All the chemicals showed an around 30-50% decrease in effectiveness after 240 hours of treatment. The model predictions in present study could be help in timely, effective and ecofriendly management of leaf mold disease in tomato.

A Study on the Religiosity of Filial Piety Ethics in Daesoonjinrihoe (대순진리회의 효 윤리에 나타난 종교성 연구)

  • Cha, Seon-keun
    • Journal of the Daesoon Academy of Sciences
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    • v.27
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    • pp.171-200
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    • 2016
  • This paper will analyze the filial piety based ethics of Daesoonjinrihoe (大巡眞理會) and the traditional filial piety of Confucianism (儒敎), Buddhism (佛敎) and Taoism (道敎) through comparing and contrasting their unique systems. The traditional Korean ethics regarding filial piety are in great need of reformation as the relationship between the parents and children should not be vertical or unilateral but parallel and reciprocal. However, there have not been sufficient in-depth studies on this specific ideology and alternative approaches. Regarding this prospect, one representative Korean indigenous new religion, Daesoonjinrihoe has emerged and directly engages in the collision between traditionalism and modernity. The modernity of Daesoonjinrihoe, enables the observation of how the filial piety based ethics have developed within a system of doctrine and thereby provides an exemplary model of traditional filial piety reimagined in accordance with modern sensibilities. A brief summary of comparative findings is as follows: First, Daesoonjinrihoe and Confucianism have taken serving parents with respect as an ethic within filial piety, but Confucianism engenders this ideal through the unilateral and unconditional sacrifice of younger people based on patriarchal feudalism whereas Daesoonjinrihoe has rejected such unilateral sacrifice and instead promotes mutual beneficience between parents and children. This difference occurs, in part, due to the filial piety of Confucianism rising in the midst of the feudal order whereas the ideology of Daesoonjinrihoe contains ideals such as "the reciprocation of favor for mutual beneficence (報恩相生)" and "respect for humanity (人尊)," both of which serve as key principles of the new religious world as envisioned by Daesoonjinrihoe. Second, filial piety in Buddhism and Taoism tends to be passive and inactive and is often expressed by praying for happiness and longevity for one's parents while they are alive and later praying for the heavenly rebirth of one's parents after they die. The filial piety of Daesoonjinrihoe also partially contains such ideas, however; they are extended much further and arrive upon novel and profound expressions. The spectrum of the filial piety in Daesoonjinrihoe expands to the extent children perform actions to resolve their parent's sins and pave a new road for their parents. This filial piety requires a cultivation practice from both parents and children. This system of dual cultivation was established because the world-view of Daesoonjinrihoe enables both parents and children to enjoy happiness and wealth both of which are achieved through the completion of religious objectives following cultivation practice. Third, Confucianism and Daesoonjinrihoe hold memorial services for ancestors with sincerity as an expression of filial piety. Filial piety in the Confucian context excludes ideas from Shamanism and thereby memorial services are held for impersonal entities, however; in the Daesoonjinrihoe context, memorial services are held for personal-entities. Accordingly, holding a memorial service for ancestors with sincerity has a greater sense of realism in Daesoonjinrihoe than it does in Confucianism. Fourth, while Confucianism and Daesoonjinrihoe both aim to requite the grace received from ancestors, the contents of grace and reciprocation of favors (報恩) are viewed differently. In Confucianism, since the ancestors existed previously and bestowed the gift of life to their children and indirectly, all of their descendents. Therefore, memorial services for ancestors are held to convey gratitude and filial piety. However, in Daesoonjinrihoe, ancestors not only bestowed the gift of earthly life to their descendents, in the spirit realm, ancestral spirits also spend sixty years accumulating the merit necessary to imbue each of their descendents with spiritual insight. Consequently, filial piety is expressed through memorial services as well as spiritual cultivation. Fifth, in Confucianism, achieving the fame and prestige indicative of success in the mundane world can be an act of filial piety as it would bring pride to one's ancestors, but in Daesoonjinrihoe, succeeding in religious objectives through spiritual cultivation is considered to be a higher form of filial piety. Sixth, Confucianism, Buddhism and Taoism all observe filial piety as system of familial ethics based in morality. This is likewise true of Daesoonjinrihoe, however; Daesoonjinrihoe confers greater importance on filial piety as an essential form of ethics for religious redemption. This is due to the Daesoon interpretation that the absence of filial piety was the direct cause which led to the sickened state of the world and its collapse. Forgetting the grace of parents who have given the gift of life or the grace of ancestral spirits who have accumulated merit on behalf of their descendents are acts of ingratitude which are unacceptable during the period of Reordering of the Universe. Judging from these findings, Daesoonjinrihoe embraces parts of traditional filial piety as it exists in Confucianism, Buddhism and Taoism, but it does so on the ground of its own unique culture. Through re-interpretation and re-creation, ideas regarding filial piety are being further developed. Namely, filial piety in Daesoonjinrihoe is regulations founded upon the reciprocation of favors for mutual beneficence and respect for humanity. Therefore, it is understood as a concept wherein one's own cultivation practice is performed in order to reach religious objectives, the perfection of personal character, and spiritual insight. This requires that even recipents of filial piety (i.e., parents) perform certain cultivation practices to enjoy happiness and wealth. Additionally, filial piety in Daesoonjinrihoe manifests a reinforced religious character and also serves as a system ethics which is soteriologically essential for salvation during the period known as the Reordering of the Universe.