• Journal of the Korean Geotechnical Society
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• v.16 no.1
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• pp.131-143
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• 2000

Several theoretical analyses are performed to predict the vertical load on embankment piles with cap beams. The piles are installed in a row in soft ground below the embankment and the cap beams are placed perpendicular to the longitudinal axis of the embankment. Two failure mechanisms such as the soil arching failure and the punching shear failure are investigated according to the failure pattern in embankment on soft ground supported by piles with cap beams. The soil arching can be developed when the space between cap beams is narrow and/or the embankment is high enough. In the investigation of the soil arching failure, the stability in the crown of the arch is compared with that above the cap beams. The factors affecting the load transfer in the embankment fill by soil arching are the space between cap beams, the width of cap beams and the soil parameters of the embankment fill. The portion of the embankment load carried by cap beams decreases with increment of the space between cap beams, while it increases with the embankment height, the width of cap beams, the internal friction angle and cohesion of the embankment fill. Thus, the factors affecting load transfer in embankment should be appropriately decided in order to maximize the effect of embankment load transfer by piles.

• Journal of Korean Society of Forest Science
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• v.94 no.4 s.161
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• pp.269-276
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• 2005

This research was carried out in order to make clear population and community structure of Berchemia berchemiaefolia forest surveyed from October 1998 to October 2004 which was located in Janggok-Ri Gunwi-Gun, Kyungpook province. B. berchemiaefolia community was classified into 3 groups such as Picrasma quassioides group, Carex ciliata-marginata group and Typical group using ZM methods. In case of floristic composition structure according to crown stories, B. berchemiaefolia occupied 42.82%, 34.43%, and 5.28%, in tree layer, subtree layer and shrub layer, respectively. Importance value of Quercus variabilis, Platycarya strobilacea and Quercus serrate species was generally high. Species diversity of Picrasma quassioides group indicated 1.6669 which was highest value among the 3 vegetation groups. Population of B. berchemiaefolia showed overall the structure of reverse J type in DBH class showing the peak between 6 cm and 10 cm and reached 14 meters in height class, and the age structure of the population ranged from 11 years to 60 years showing regular distribution type. Stump sprout or/and epicormic branch made numerous stems around original stump of previous generation which was considered to be cut and disappeared by residents. Seedlings or/and saplings of B. berchemiaefolia were intensively occurred in the opened areas of forest road. Those things could be certainly considered to establish management plan of B. berchemiaefolia forest.

• Journal of Korean Society of Forest Science
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• v.83 no.4
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• pp.450-459
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• 1994

The damage by the black-tipped sawfly, Acantholyda posticalis posticalis Matsumura, has been increasing at several locations in central part of the Korean peninsula. This study was undertaken at selected plots in Kapyung-gun, Kyunggi Province and Hongchon-gun, Kangwon Province from 1984 to 1987. The purpose of this study was to provide basic information for integrated control of this pest and to determine the economic threshold by investigating the pest host interactions with special reference to damage analysis. The results obtained were as follows ; 1. The damage was more severe at upper part than at lower part of the crown. The vertical distribution of dry weight of damaged trees above ground showed L-type distribution, whereas that of healthy trees showed C-type distribution. 2. The needle loss by sawfly reduced both of height and the diameter growth of the main stem. The growth reduction occurs when the needle loss is 50% or higher. About 10% of tree growth was reduced at 50% of needle loss. 3. The reduction of diameter growth was more severe at upper part than at lower part of the main stem. 4. Volume growth was reduced when more than 50% of the needles were damaged after three years of the sawfly infestation. Reductions of total volume increment at the levels 70% and 90% of needle damage were 9% and 20%, respectively.

• Horticultural Science & Technology
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• v.18 no.4
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• pp.518-522
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• 2000

The objective of this research was to determine the effect of waste nutrient solution (WNS) on growth and development of poinsettia 'Gutbier V-10 Amy'. To achieve this, WNS collected from rose grown in greenhouse was diluted with various times and 500 mL of each solution was applied every week. Then growth characteristics and nutrient uptake were determined at 180 days after transplanting. The treatment of undiluted WNS had highest plant height and length of branch among treatments tested, but there were no statistical differences in the number of bract and branches. Undiluted WNS had higher leaf number, leaf length, leaf width, fresh weight, and dry weight than any other treatments tested. There was also a trend that increased dilution times of WNS resulted in decreased plant growth. Undiluted WNS had higher chlorophyll content than Hyponex treatment, but diameter of crown did not show significant differences among treatments. In the analysis of root media collected at 6 months after fertilization, the treatment of undiluted WNS had higher electrical conductivity and organic matter content than other treatments, but the Hyponex treatment had higher phosphorus concentration than other treatments tested.

• Restorative Dentistry and Endodontics
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• v.18 no.2
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• pp.357-367
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• 1993

The purpose of this study was to evaluate the fracture strength of class II restored premolars with amalgam, posterior composite, amalgam - Ketac silver, resin - Ketac silver restorations at marginal ridge. Fifty extacted maxillary and mandibular premolar teeth that were caries free, fracture free, and restoration free were selected and randomly divided into five groups : Group 1 : 10 intact teeth, Group 2 : 10 teeth with class II cavities and restored with, amalgam, Group 3: 10 teeth with class II cavities and restored with posterior resin, Group 4 : 10 teeth with class II cavities and restored with amalgam - ketac silver, Group 5 : 10 teeth with class II cavities and restored with resin - Ketac silver. All teeth were mounted in base of dental stone within metal rings of 2cm diameter, exposing only the crown portion. Class II mesio - occlusal or disto - occlusal cavities were prepared into specimens of Group 2 through 5 by using a No. 710 fissure bur. The occlusal portion was prepared to a faciolingual width of 1.5mm and a pulpal depth of 1.5mm. The proximal protion was prepared to a faciolingual width of 4mm, a occlusogingival height of 4mm, and a gingival floor of 1.5mm. The teeth in Group 2 and 3 were resotored with silver amalgam apd posterior resin respectively. In Group 4 and 5, proximal portions were first filled with Ketac silver 1.5mm gingivally and remaining cavities were restored with amalgam and posterior resin respectively. All specimens were stored in 100 % relative humidity at $37^{\circ}C$ for 48 hours before testing. All teeth were subjected to a compressive load in a Universal Instron Testing Machine at marginal ridges. The loads required to fracture the restorations were recorded in killograms and the data obtained were subjected to statisticall analysis. The results were all follows : 1. The fracture strength of Group 1 which were unprepared were $100{\pm}10.1\;kg$ and the higher values than Group 2, 3, 4, 5 which were prepared and resotred. 2. In restored groups, Group 2 had the higher fracture strength($81.8{\pm}12.4\;kg$) than other groups and Group 4 had the lowest fracture strength($66.8{\pm}9.2kg$). 3. There were significant differences between fracture strength of between Group 1 and Group 3, 4, 5(P<0.05), but not significant difference between fracture strength of Group 2, 3, 4, 5(P>0.05).

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.31 no.3
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• pp.248-254
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• 2005

The purpose of this study was to investigate the distribution of stress within the regenerated bone surrounding the implant using three dimensional finite element stress analysis method. Using ANSYS software revision 6.0 (IronCAD LLC, USA), a program was written to generate a model simulating a cylindrical block section of the mandible 20 mm in height and 10 mm in diameter. The $5.0{\times}11.5-mm$ screw implant (3i, USA) was used for this study, and was assumed to be 100% osseointegrated. And it was restored with gold crown with resin filling at the central fossa area. The implant was surrounded by the regenerated type IV bone, with 4 mm in width and 7 mm apical to the platform of implant in length. And the regenerated bone was surrounded by type I, type II, and type III bone, respectively. The present study used a fine grid model incorporating elements between 250,820 and 352,494 and nodal points between 47,978 and 67,471. A load of 200N was applied at the 3 points on occlusal surfaces of the restoration, the central fossa, outside point of the central fossa with resin filling into screw hole, and the functional cusp, at a 0 degree angle to the vertical axis of the implant, respectively. The results were as follows: 1. The stress distribution in the regenerated bone-implant interface was highly dependent on both the density of the native bone surrounding the regenerated bone and the loading point. 2. A load of 200N at the buccal cusp produced 5-fold increase in the stress concentration at the neck of the implant and apex of regenerated bone irrespective of surrounding bone density compared to a load of 200N at the central fossa. 3. It was found that stress was more homogeneously distributed along the side of implant when the implant was surrounded by both regenerated bone and native type III bone. In summary, these data indicate that concentration of stress on the implant-regenerated bone interface depends on both the native bone quality surrounding the regenerated bone adjacent to implant and the load direction applied on the prosthesis.

• Journal of the Korean Society of Costume
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• v.43
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• pp.243-258
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• 1999

This is a study of CHOK-DU-RI(族頭里) a black crown-like headpiece worn by woman on formal occasion in Chosun Dynasty and has succeeded until now. CHOK-DU-RI was originated by BOKTAK worn by Mongolian noblewomen and inflowed to the last period of Koryo dynasty under occupation of Yuan. The documentary records of O-JU-YON-MUN-CHSNG-JON-SAN-KO( by Lee Kyu-kung CHUNG-JANG-KWAN-JON-SUH by Lee Tock-mu and KO-SA-TONG by choe Nam-sun verify CHOK-DU-RI is a custom of mongolian fusion that was affected by KO-KO of Yuan and was formed. Ko-Ko is the same as BOKTAK. It is assumed KO-KO is a borrowed name as its transcription varies. The name was given according to its appearance which is certified by the record CHANGCHUN-CHIN-IN-SEO-BANG-YU-RAM-KI. It says that it can be simply named KO-KO as its edge is alike ad goose or a duck. In addition KO-Ko was called CHOGTAI in case of being added a camel fur that is JUGDUR. CHOGTAI similarily pronounced with CHOK-DU-RI which of being added a camel fur that is JUGDUR, CHOGTAI similarily pronounced with CHOK-DU-RI which provd CHOK-DU-RI was originated in Mongol. The shape of BOKTAK is very high and wided toward the top with the top with the angle getting more pointed and a feather stuck on the side. But its height got lower and its size smaller as it did gradually Koreanized to a CHOK-DU-RI. The use of CHOK-DU-RI has been settled since the last period of Chosun Dynasty. It came to stay as a popular custom when King Young-jo and Jong-jo wanting to do away with the corrupt practice of KA-CHE encouraged women at that time to do their hairs with CHOK-DU-RI instead of KA-CHE. It is as follows the classification of CHOK-DU-RI. First classified by a use group is divided into ceremonial use such as the seven treasures CHOK-DU-RI and jeweled CHOK-DU-RI. Hereby it is assumed that CHOK-DU-RI was used regardless of fortune. Secondly it varies by its type of frame. There are SOM CHOK-DU-RI OHT CHOK-DU-RI and O-YOM CHOK-DU-RI a kind of SOM CHOK-DU-Ri formed a base of O-YOM-MO-RI. The third group by jeweling has WHE-BONG CHOK-DU-RI and TA-BONG-CHOK-DU-RI JEwele CHOk-DU-RI can be still seen being commercially lent and worn by the brides at nuptical ceremonies performed in tradition of fashion and when worn bya bride as she gives her parents to her parents-in-law.

• Korean Journal of Remote Sensing
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• v.25 no.5
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• pp.445-454
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• 2009

Localized unprecedented torrential rain and heavy rainfall cause repeated damages and make it difficult to detect and predict the landslide caused by heavy rainfall. To analyze the landslide characteristics of Inje area this study used satellite images photographed after the occurrence of landslide caused by the typhoon Ewiniar occurred in July, 2006, and for GIS analysis purpose, interpreted the satellite images (SPOT5) visually to digitize into developing parts, water traveling parts and sediment parts. For analysis of spatial characteristics, landslide areas obtained from visual interpretation of digital map, 3rd & 4th forest vegetation maps and detailed soil map and grids were overlaid and analyzed. As a result, in regard to topographic features, landslide occurred at places, of which average slope is $26.34^{\circ}$, had south, south-east, south-west aspects and average altitude of 627m. From hydrological analysis, it was found out that water traveling area rapidly spread approaching water traveling area and sediment area. From forest type analysis, it was found out that landslide occurrence was high in pine woods, and in terms of girth class attribute, landslide occurred in small-sized woods, in which the crown occupancy of trees that have the diameter at breast height, 6~16cm, was greater than 50%. From the analysis of soil series, landslide areas constitute 37.85% of OdF and 37.35% of SmF, which had sandy loam soil and excellent drainage capacity. Through this study, landslides in Inje area were characterized and SPOT5 images of 2.5m resolution could be used. But there was a difficulty in determining water traveling parts adjacent to urban area.

• Journal of Bio-Environment Control
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• v.30 no.3
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• pp.175-182
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• 2021

This experiment was conducted to find out the possibility of use of reused rockwool and comparison of growth, productivity and quality of tomatoes according to the use of rockwool and coir medium. The experiment was conducted in an automatic controlled greenhouse at Andong National University, College of Life Science, located in Andong, Gyeongsangbuk-do.. As a result of the experiment, there was no difference in the number of leaves, plant height, and leaf area between treatments, and the crown diameter was slightly higher in rockwool medium, also there was no difference between reused rockwool and coir medium. Fruit productivity showed different responses depending on the cultivation environment, but there was no significant difference between rockwool, reused rockwool and coir medium. In addition, the quality of fruit was observed to be different according to the concentration of EC in the medium. Therefore, in tomato hydroponic cultivation, there was no difference in the type of medium in growth, productivity, fruit quality and the environmental and water management had a great effect, and it is expected that the reuse of rockwool will have a positive effect on the economic point of view.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.35 no.4
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• pp.75-83
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• 2023

Apart from implementing hardware solutions like raising the crest freeboard of coastal structures to efficiently counter wave-overtopping, there is a simultaneous requirement for software-driven disaster mitigation strategies. These tactics involve the swift and accurate dissemination of wave-overtopping information to the inland regions of coastal zones, enabling the regulation of evacuation procedures and movement. In this study, a method was proposed to estimate wave-overtopping by utilizing the temporal variation of wave heights exceeding the structure's crown level, with the aim of developing an on-site wave measurement system for providing wave-overtopping information in the field. Laboratory model experiments were conducted on vertical seawall structures to measure wave-overtopping volumes and wave runup heights under different wave conditions and structural freeboard variations. By assuming that the velocity of water inundation on the top of the structure during wave-overtopping events is equivalent to the long-wave velocity, an overtopping discharge coefficient was introduced. This coefficient was utilized to estimate the rate of wave-overtopping based on the temporal changes in wave runup heights measured at the top of the structure. Upon reasonably calculating the overtopping discharge coefficient, it was verified that the estimation of wave-overtopping could be achieved solely based on the wave runup heights.