• Steel and Composite Structures
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• v.36 no.5
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• pp.553-568
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• 2020

Steel-concrete composite structures have been extensively used in building, bridges, and other civil engineering infrastructure. Shear stud connectors between steel and concrete are essential in composite members to guarantee the effectiveness of their behavior in terms of strength and deformability. This study focuses on investigating the shear stiffness of headed studs embedded in several types of concrete with wide range of compressive strength, and their effects on the elastic behavior of steel-concrete composite girders were evaluated. Firstly, totally 206 monotonic push-out tests from the literature were reviewed to investigate the shear stiffness of headed studs embedded in various types of concrete (NC, HPC, UHPC etc.). Shear stiffness of studs is defined as the secant stiffness of the load-slip curve at 0.5V_u, and a formulation for predicting defined shear stiffness in elastic state was proposed, indicating that the stud diameter and the elastic modulus of steel and concrete are the main factors. And the shear stiffness predicted by the new formula agree well with test results for studs with a diameter ranging from 10 to 30 mm in the concrete with compressive strength ranging from 22.0 to 200.0MPa. Then, the effects of shear stiffness on the elastic behaviors of composite girders with different sizes and under different loading conditions were analyzed, the equations for calculating the stress and deformation of simply supported composite girders considering the influence of connection's shear stiffness were derived under different loading conditions using classical linear partial-interaction theory. As the increasing of shear stiffness, the stress and deflection at the most unfavorable section under partial connected condition tend to be those under full connected condition, but the approaching speed decreases gradually. Finally, the connector's shear stiffness was recommended for fully connection in composite girders with different dimensions under different loading conditions. The findings from present study may provide a reference for the prediction of shear stiffness for headed studs and the elastic design of steel-concrete composite girder.

• Journal of Korean Society of Rural Planning
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• v.19 no.4
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• pp.17-32
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• 2013

Reckless development policy, which has continued during the past several decades, caused landscape damage. In order to solve this problem, it is very urgent to conserve the habitat and to establish systematic database. Recently, various researches related to landscape damage have been conducted actively and the necessity of landscape ecological planning based on the biotop mapping has been issued as one of the solutions. Therefore, the purpose of this study is to select the study area, which is located in Guji-meon, Dalseong-gun, Daegu and will be formed into Daegu Science Park, and then to develop and apply the landscape ecological planning model based on biotop mapping in district unit. The results are as follows. Fist of all, according to the results of biotop classification with field survey and literature review, total 13 biotop and total 63 biotop types were classified. According to the first evaluation with B-VAT, total 19 biotop types were classified I grade including natural river with abundant plants(BA) and so on. While V grade, which has lowest value, was classified 16 biotop types including vegetable garden adjacent to river(BC). Also the second evaluation, we analyzed total 30 areas such as 1a, 1b grades, which had special meaning for the conservation of species and biotop. Next, 2a, 2b, 2c grades were analyzed total 82 areas. Secondly, in the compliance with Ecological landscape planning, we divided landscape planning model into two parts such as setting of improvement goal and detailed implement plan. For instance, setting of improvement goal, we classified 9 parts such as conservation region and parts of detailed implement plan, we classified total 28 planning indicators with 4 view such as the region which should be special protected from nature and landscape. Lastly, with the developed landscape model we applied to research areas, made maps, and differentiate proposals in each region. Specially, the final master plan was made to help understand the contents of detailed landscape planning. This study will be a useful data, which can solve the landscape damage problem systematically and control it landscape-friendly with biotop classification, evaluation, landscape ecological planning model, and application method which we developed.

• Korean Journal of Environment and Ecology
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• v.30 no.2
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• pp.199-213
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• 2016

This study aimed to analyze the vegetation characteristics of the coastal forests and to figure out if there is possibilities to develop the forests into mixed stand multistory forests and to suggest some sound management practices. The vegetat- ion structure and flora of four sites; Kijipo, Chunjangdae, Janghang and Kusipo in the west coastal forests in Korea were investigated and analyzed in the present study. In the every site, Pinus thunbergii was dominating the tree layer in the forests. And P. densiflora, Robinia pseudoacacia, Quercus serrata, Prunus sargentii var. sargentii, Q. acutissima and Castanea crenata were dominating the subtree layers in some sites. P. thunbergii stands in four sites would maintain for a while since the populat- ion density of middle aged group is higher than those of young and old groups. According to the geographical location conditions, there is a possibility that the coastal forests in Kusipo site would progress into oak tree stands in the long run. The biodiversity was quite high to have 205 taxa in the study sites. To induce the coastal forests into multistory forests, P. thunbergii stands need to be thinned. And then creating the environment including making some pathways and site usage rest-riction is needed to let new diverse plants could come in and grow for a success-ful multistory forests.

• Journal of Science of Art and Design
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• v.13 no.1
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• pp.61-86
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• 2008

Buddhism and Buddhist art originated in India, but when they were introduced to different countries, they created an international environment. Buddhism was introduced as cultural package, with written texts, visual images, rituals, and the organization of monasteries. Buddhist art originated in India during the reign of King Asoka and then was developed under the political, intellectual, artistic, religious, social and natural environments of the regions. The stupa and the chaitya halls create monastic environment. The natural environment of the trade routes and caravans in the Central Asian deserts preserved brilliant-colored murals and helped spread tram India to China. When Buddhism and Buddhist art were introduced to China, Korea, and Japan, Buddhism became a part of government institution and social organization. Gigantic statues were carved in caves in mountains for political purposes. The Chinese transformed the stupa into a square pillar and created pagodas with tiled roofs in tower forms. Koreans not only transmitted the Buddhist art from China to Japan, but it also changed it with originality in the iconography of the pensive bodhisattva images and in the architecture of Seoggulam. The official ideology of Neo Confucian philosophy brought the rise of Chan Buddhism. Zen monasteries in Japan created unique environments by establishing the Zen Buddhist garden. to prompt believers to meditate. An important development in Buddhist art is the Esoteric Buddhist art in China and Tibet. This category belongs to the intellectual, religious as well as artistic environments. The Tibetan deities with consorts in their embrace symbolize the union of the god and the devotees. Buddhist art created a unique environment that was spread out to many nations and changed greatly over time.

• Korean Journal of Environment and Ecology
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• v.29 no.6
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• pp.842-849
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• 2015

This study investigated the effects of rare-earth fertilizer on the shoot cuttings' rooting of Vitex rotundifolia L. and Tamarix chinensis Lour. The shoot cutting test was carried in 2008 and the main results are summarized as follows. The rate of rooting and the average roots increased in both number and length when rare-earth fertilizer is treated in V. rotundifolia and T. chinensis in comparison to those of the untreated control plot. In particular, when rare-earth fertilizer is diluted with water 1/2500, the rooting outstandingly increases. This result is almost similar to the effect of the rooting stimulant, IAA. Although there is no differentiation in its rooting rate according to the density, the rooting of T. chinensis shows a 100 percent effect on in the entire treated plot but not in the untreated control plot, so it is usable as a rooting stimulant. As for shoot cuttings' rooting, depending on the time immersed in diluted solution of rare-earth fertilizer, both V. rotundifolia and T. chinensis showed relatively higher percentages in all treatment plot immersed for 60 minutes than for 10 minutes. In conclusion, considering the results of the rooting percentage and the average number and length of roots of V. rotundifolia and T. chinensis, the shoot cuttings' rooting appeared higher in percentage when they were immersed in the rooting stimulant for sixty minutes with a lower density than 1/2500. This result shows that rare-earth fertilizer can be utilized as an alterative for IAA rooting stimulants currently available in the market.

• Journal of Environmental Science International
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• v.11 no.3
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• pp.139-148
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• 2002

When the natural villages in Jeju province are incorporated into the district of city planning, they are considered to be a small-scale residential districts. Therefore, a garden city should be planned that considers the characteristics of the villages to implement an appropriate street system, to use the area effectively, and to harmonize the villages with the surrounding communities. There have been an especially large number of problems with the street system in the city of Seogwipo, which was notified as the area of natural settlement. This study analyzes the problems inherent in street planning and the present condition of roads whose construction has been postponed for a long time due to several problems including an inappropriately planned street system. Based on the research of various documents, a practical street system has been investigated. Most of the residents in natural settlement units demand use of the continued the existing roads as well as the implementation of an effective street system. They ask for street planning under which the involved construction would take only a short period of time and would result in only minimal damage to their existing properties. Therefore, the street system should be planned so as to preserve the nature-friendly features of natural settlements, their surroundings and tourism resources. Even after streets hwve been planned and their completion you has been established, the plan should be continuously evaluated, analyzed and compared with other alternatives. The street plan should continuously incorporate improvement measures which would satisfy various aspects of the street system including land use, traffic demand, and future population demands. Both the amount of money to be invested and economical efficiency should be considered for street planning since the street system has a great impact on many industries. Unnecessary costs related to excessive road construction should be avoided. The street network plan should also include the complete evaluation of the natural topography as well as the surrounding. Considering these views, the data concerning the current condition of the city and the related investigation play an important role in establishing a street plan. However, the investigation of future construction plans by the city is as of yet at a very early stage. Therefore, there is an urgent need for the investigational study of the current city development plans. The street system for the natural settlement area should be established only after the thorough investigation of all aspects of street planning. In addition, the plan should be flexible enough to consider the characteristics of Jeju.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.28 no.4
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• pp.105-111
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• 2010

This research aims to grasp the main factors of the image of Xi'an Ming City Wall Park and the harmony level with city walls and moat based on citizen's consciousness to improve the future design, field survey and the POE method are employed to analyze the image factor and harmony level of the Xi'an Ming City Wall Park. In the literature survey, the related materials were collected to obtain the most useful information for references, POE study of the Xi'an Ming City Wall Park were conducted. The instrument for survey is a questionnaire that includes a portion of questions regarding Xi'an Ming City Wall Park and the design intention of the surroundings of city wall. Data were analyzed using the Statistical Package for the Social Science (SPSS17.0 for Windows). Multiple regression analysis, and correlation analysis were employed along with the use of general descriptive data analysis. The factor analysis of the image of Xi'an Ming City Wall Park identified three factors, "environment" factor, "convenience" factor, "cultural aesthetics" factor, and the most important factor is "environment" factor. Among 14 landscape elements, paving, garden architectures and entrance spaces were identified as important variables which significantly affect the overall level of harmony with the city wall, and the space for rest; waterscape and paving were identified as important variables which significantly affect the overall level of harmony with the moat.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.30 no.3
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• pp.68-79
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• 2012

This study examines features in using Japanese apricots that assume a leading place with a special symbolism among various species of trees adopted to traditional gardens from a landscaping view. Specific aspects of how Japanese apricots were adopted to traditional gardens are as follows. First, while Japanese apricots are used in modern landscape space, there traditionally were six types in use of Japanese apricots as Tammae(探梅) Jungmae(庭梅) Bunmae(盆梅) Byoungmae(甁梅) Chomae(造梅) and Mukmae(墨梅). Second, Japanese apricots planted in gardens[庭梅] were placed mainly in a front yard of Sarang-Chae(the men's part of a traditional house) took a central area because symbolism and ornamental values of Japanese apricots suited what classical scholars sought. Preferred planting sites at that time include south of the building, the yard of Sarang-Chae, space in front of windows and next to fences and waterside. Third, Japanese apricots in traditional gardens were planted in five ways; Dansik(單植) Daesik(對植) Gunsik(群植) Yeolsik(列植) Honsik(混植). Dansik was the most common way in planting Japanese apricots and Daesik intended to enhance orderedness and symbolism of space. Japanese apricots for appreciating in an open field took the form of Gunsik in general but Honsik was also used with species of special symbolism. This study offers an opportunity to grasp traditional planting methods of Japanese apricots based on understanding of cultural aspects of Japanese apricots by focusing on Japanese apricots, the representative traditional species of trees. Results of the study would help to recognize the need to newly understand Japanese apricots and be useful information to plant and use Japanese apricots in a traditional way.

• FLOWER RESEARCH JOURNAL
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• v.19 no.1
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• pp.64-67
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• 2011

In order to research the effects that indoor plants of apartments in Seoul have on the happiness index, we tried to analyze relationships between indoor plants which are nearest to the residents and happiness which is the final goal of the residents, and for this 200 residents who live in apartments in the Seoul city area were sampled. This study was based on the precedent studies of the facts that horticultural therapy and function of plants had already proven the affirmative roles of plants to people. The results were as follows. Residents reported that they were happiest when the plants were blooming(57%), when the plants were sprouting(33%), when repotting(2%), when distributing(2%) and others(7%). The residents exposed to indoor plants were in direction proportion to the happiness index within 1hour. Happiness indexes of the residents who cared for potted plants were by themselves was 67.90, when family members cared for the plants, 65.09, and when others cared, it was 64.79. The preference of indoor plants and the happiness index according to the scale of interior gardens were in direct proportion. Lastly, the happiness index of residents according to the number of potted plants, was in direct proportion: the more potted plants, the greater the happiness index.

• Asian Journal of Turfgrass Science
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• v.20 no.2
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• pp.223-235
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• 2006

Soil testing laboratories unfamiliar with turfgrasses will often overestimate the plant's need for phosphorus and underestimate the need for potassium. This is partly due to differences in rooting between grasses and many garden plants and crops. The grasses are generally more efficient in extracting phosphorus from the soil, reducing their need for phosphorus fertilizer. The fact that crop yield is often the primary objective in field crop production, and is usually of little interest in turfgrass management, may affect soil test interpretation for potassium. Potassium levels above those required for maximum tissue yield of grasses may improve stress tolerance and turfgrasses will usually benefit from higher applications of this element. There are also diffrrences in soil testing philosophies. Some laboratories use the sufficiency level of available nutrients(SLAN) approach, whereas others prefer the basic cation saturation ratio(BCSR) approach. Some will use a combination of the two methods. The use of the BCSR theory easily lends itself to abuse and questionable fertilizer applications and products are sometimes recommended citing imbalances in cation ratios. The usefulness of the BCSR ratio theory of soil testing varies with soil texture and interpretations on tests performed on sand-based media are particularly a problem. Other soil testing problems occur when sand-based media used on sports fields and golf greens contain free calcium carbonate. The ammonium acetate extractant at pH 7.0 dissolves excessive amounts of calcium that can bias cation exchange capacity measurements and measurements of cation ratios. Adjusting the pH of the extractant to 8.1 can improve the accuracy of the testing procedure for calcareous media.