• Journal of the Korean Institute of Landscape Architecture
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• v.22 no.2
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• pp.123-132
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• 1994

Tow-year-old Taxus cuspidata shoot cuttings were treated with various electrical impacts of cathode on their base and anode on their apex by normal and reverse source. The cuttings were previously treated with 200ppm IBA for 12 hours and the rooting percentage, the length, and the weight of roots were checked. The auxin contents of cuttings were also examined by high-performance liquid chromatography. The results obtained on this study are as follows; 1. Normal treatment, cathode into the base and anode into apex, seemed to accelerate rooting while reverse treatment showed less effective than normal treatment on rooting, but both treatments were more effective than control. 2. The impact of electrical treatment at 30mV for 30min has a remarkable effect on the percentage rooting, the length, and the weight of roots. 3. Root primordia were formed at the basipetal end of cuttings where the end of primary pith ray meets the cambium in control treatment and formed at the basal part of cuttings irregularly in electrical treatment. 4. High-performance liquid chromatography showed electrical treatment was more effective on auxin accumulation than control, and 30mV-30min was the most effective on auxin accumulation.

• The Journal of Korean Academy of Prosthodontics
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• v.38 no.3
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• pp.348-357
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• 2000

The purpose of this study is to examine the effect of partial osseointegration situation on bone loading patterns around two different free-standing screw shaped implants (Nobel Biocare, Gothenburg, Sweden and Degussa-Huls, Hanau, German). Two dimensional axisymmetric Finite element models of two implants(10mm length and 4mm diameter) were created according to different bone quantity, quality and osseointegration ratio in maxilla and mandible bone. At the same time uni-cortical and hi-cortical fixation were analyzed. Generally, full bond case showed less stress than partial bond case in overall area and mandibular model showed less amount of stress than that of maxilla model. Maximum stress of the Branemark implant is higher than that of ANKYLOS regardless of bonding ratio at crestal and apex region. However, more stress concentration was noted in ANKYLOS implant at screw body area especially in mandible. The effect of bicortical fixation on crestal bone stress reduction is dramatical in mandible however, there was no significant effect in maxillary case. The effect of partial bond on stress distribution was more significant at screw body and apex region than in crestal region. Partial bond cases demonstrated greater stress accumulation in trabecular bone than cortical bone. It is concluded that the more accurate model of implant and bone which affects stress and strain distribution is needed to mimic in vivo behavior of implants.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.12 no.2
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• pp.133-139
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• 2001

Background and Objectives : There are so many methods to investigate the causes of voice disorders. However, they were almost invasive or non-physiologic methods. And none of them showed the laryngeal movements. Phonation pharyngogram is non-invasive method to see the laryngeal movement directly. Authors studied to evaluate the availability of phonation pharyngogram in laryngeal nodule. Materials and Methods : 30 laryngeal nodules and 10 control groups were evaluated. Acoustic analysis and maximum phonation time were measured and pharyngogram was taken during sustaining /a/ phonation immediately after swallowing the barium. We measured the width of hypopharyngeal wall, shape of hypopharyngeal wall and pyriform sinus apex, level difference between both true vocal folds, angle of subglottis, location of true vocal folds, elevated distance of vocal folds and shape of c-spine. Results : Jitter, Shimmer of laryngeal nodule were higher than control group and maximum phonation time was shorter in laryngeal nodule. There was a significance in width of hypopharyngeal wall, shape of pyriform sinus apex, level difference between both true vocal folds, elevated distance of vocal folds and shape of c-spine. Conclusions : Authors knew that there were differences when we used the phonation pharyngogram between normal group and laryngeal nodule group.

• Restorative Dentistry and Endodontics
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• v.16 no.2
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• pp.118-125
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• 1991

Eighty - eight recently extracted teeth were used to evaluate the leakage characteristics of the following retrofilling materials; amalgam, zinc oxide eugenol cement, glass - ionomer cement, and cermet glass - ionomer cement. Root canals were prepared with step - back method and obturated with gutta percha and zinc oxide eugenol sealer. Root apex were resected 2 mm from apex and class I cavities were prepared with 2 mm or 4 mm depth. The cavities were filled with above materials. After application of varnish on all surface except resected surface, the roots were placed in 1 % methylene blue solution for 6 days. After longitudinal polishing to expose cental parts of filled materials, penetrated depths of dye were measured. The results were as follws. 1. As retrofilling material, glass ionomer cement filling groups showed less leakage than the other groups except zinc oxide eugenol cement filling group(p<0.01). 2. Amalgam filling groups had greater leakage than zinc oxide eugenol cement filling group(p<0.01). 3. 4 mm depth of retrofilled cavity had no effect on leakage characteristics compared with 2 mm depth cavity(p>0.05). 4. Glass ionomer cement and cermet glass ionomer cement filling groups showed less apical leakage than amalgam filling groups. But there was no statistical significance(p>0.05). 5. There was no difference in apical leakage between glass ionomer cement filling groups and cermet glass ionomer cement filling groups(p>0.05).

• Journal of the Korean Vacuum Society
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• v.7 no.3
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• pp.214-220
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• 1998

We have studied the factors influencing the growth rate of TiN deposited from TDEAT using a bubbler. The growth rate of TiN was primarily dependent on the bubbler temperature, deposition temperature, gas delivery line conductance and carrier gases. In addition, the heating of the gas line through which carrier gas was delivered to the bubbler increased the growth rate slightly. Also heating of the delivery gas line between the bubbler and the chamber caused the increase of the growth rate of TiN, Showing the Arrehenius behaviour with the activation energy of 0.2 eV.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.13 no.1
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• pp.107-115
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• 1983

This study was performed in order to analyse the morphology of maxillary sinus on orthopantomogram. The author anlaysed the anterior-posterior width of mesial wall, the extension of anterior margin in maxillary sinus and the interrelation between the root apex of maxillary 1st molar and sinus floor. The films consisted of 514 orthopantomograms divided into three groups ranging the 3rd decade, 4th and 5th decade and 6th decade. The obtained results were as follows: 1. The mean dimensions of the anterior - posterior width of mesial wall were 43.81±4.55㎜ for male and 43.80±4.49㎜for female in the right of maxillary sinus, 43.75±74㎜ for male and 43.37±3.92㎜ for female. 2. With age, the dimensional change of the anterior - posterior width of mesial wall in maxillary sinus was not observed. 3. The extension order of anterior margin of the maxillary sinus was distal to canine side, 1st premolar mesial side, canine mesial side, and 1st premolar distal side. 4. In the distance between the root apex of upper 1st molar and the maxillary sinus floor, the degree of closeness was more increased in the older-aged group than in the younger-aged group.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.42 no.4
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• pp.231-235
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• 2016

A benign cementoblastoma, which is another name for a true cementoma, is a rare neoplasm that develops from odontogenic ectomesenchyme. It is characterized by a mineralized mass attached to the apex of the root produced by neoplastic cementoblasts. More than 75% of cases arise in the mandible, with 90% of them manifesting in the molar and premolar regions. This neoplasm occurs most commonly in children and young adults, with males being affected slightly more than females. Radiographically, the tumor is observed as a well-defined radiopaque mass that is fused to a tooth root and is surrounded by a radiolucent rim. The treatment of benign cementoblastoma consists of removal of the lesion and extraction of the affected tooth. This report presents an unusual case of benign cementoblastoma in a 31-year-old female, presenting as a densely mineralized mass seen at the apex of the impacted right mandibular canine tooth on radiographs.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.41 no.11
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• pp.97-104
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• 2004

This paper proposes an efficient VLSI architecture of 9-7/5-3 Lifting DWT filters that is used by lossy or lossless compression of JPEG2000. The proposed architecture uses only internal line memories to compute Lifting-DWT operations and its PE(Processing Element) has critical path with 1 multiplier and 1 adder. To reduce the number of PE, we make the vertical filter that is responsible for the column operations of the first level perform both the row and column operations of the second and following levels. As a result, the architecture has smaller hardware cost compared to that of other architectures. It was modeled in RTL level using VHDL and implemented on Altera APEX 20K FPGA.

• Korean Journal of Plant Tissue Culture
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• v.21 no.2
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• pp.65-68
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• 1994

Plant regeneration from the stem tissue of Orostachys japonicus A. Beiger was investigated. The calli derived from shoot apex when apex when cultured on Murashige and Skoog (MS) medium supplemented with 4mg/L 2,4-dichlorophenoxyacetic acid (2,4-D)and 2 mg/L benzyl aminopurine (BAP). The calli were developed into shoot to MS medium with 0.5mg/L NAA and 2mg/L and into root with 1mg/L kinetin. The reddish pigment which might be essential for the rootregeneration was observed in the tip of regenerated root.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.41 no.4
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• pp.91-100
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• 2004

In this paper, we propose the method that analyzes the depth of object using 2 images in the disparity algorithm. It also presents the design and implementation of the proposed method for a real time processing. The proposed system uses the vertical strip structure for calculating similar pixel numbers for the processing and converts the depth of object into gray scale images in order to be displayed on various display devices. The hardware using the proposed method is operating with 30 frames/sec and verified by using the Altera APEX 20K1000EBC652-3. The proposed method is also Implemented into It by using the Hynix 0.35${\mu}{\textrm}{m}$ CB35 ASIC library and 256PQFP package.