• Korean Journal of Plant Resources
• /
• v.11 no.2
• /
• pp.157-162
• /
• 1998

This study was conducted to examine the effects of media, crown position, clone ,a nd plant growth substances upon the rootability of cuttings for the establishment of the method of mass production by cutting of Dendropanax morbifera Lev. the artifical soil mixtureof vermiculite, perlite and peatmoss (1 : 1 : 1 v/v/v) with IBA 100mg /l treatment was most effective on the rooting rate (85%) was obtained with semihardwood cuttings, which were collected early-August after the first growing seasons. The effect of crown position on rooting of cuttings were obsreved. Average percentage rooting of cuttings on crown position showed 78% , 72% and 65% in middle , upper and lower part with IBA 100mg/l treatment , respectively. Among the four treatment levels of IBA, the highest rooting rate was observed in 100mg/l IBA treatment.

• Macromolecular Research
• /
• v.13 no.2
• /
• pp.141-146
• /
• 2005

Calix[4]crown-6-2,4-bis(4-aminobutyl ether), which has a crown-6 moiety at the 1,3-position and amino function at the 2,4-position, was prepared as an intermediate for the subsequent synthesis of calix[4]crown-6-containing polyamide and polyimide using adipoyl chloride and 1,2,4,5-benzenetetracarboxylic dianhydride. The chemical structures were characterized by IR, $^{1}H NMR$ spectroscopy and elemental analysis, and some of their physical properties, including their thermal behavior, were examined. The ion binding characteristics of the monomer and polymers for alkali metal and alkali earth metal ions were measured by liquid-liquid extraction from the aqueous phase into the organic phase. It has been observed that polyamide has a high binding ability towards various metal cations as compared to polyimide, which showed cesium ion selectivity.

• Journal of Periodontal and Implant Science
• /
• v.28 no.2
• /
• pp.321-337
• /
• 1998

The aims of this study were firstly to investigate soft tissue reactions around single implant-supported crowns and secondly to compare soft tissue dimensions and conditions of the crowns in relation to interdental papillae, and lastly to investigate patients'esthetic satisfaction with their single implant-supported crowns according to the interdental papillae presence/absence. Twenty-nine patients (41 implants) whose single missing tooth in the maxillary anterior region had been replaced by single implant-supported crown participated for the study and various variables of soft tissue conditions, dimensions and crown dimensions were measured around the single implant-supported crowns at clinical examination and from study models and slides. The results showed that the soft tissue conditions around the single implantsupported crowns were similar to those around implants used for partially or totolly edentulous patients. Except for the high frequency of bleeding on probing, all other parameters revealed healthy conditions. The buccal sites of the crown had a shallow pocket comparing with other sites. At all sites of the crown, similar status of little inflammation was found. Mesial sites and central-incisor positioned implantsupported crowns had lower contact point position than distal sites and lateral-incisor positioned crowns, respectively. Mucositis index, probing depth and contact point position were significantly correlated with papillae index(p < 0.05). More inflammation and lower contact point position were found at the implant-supported crown with no interdental space than that with interdental space. Patients showed high esthetic satisfaction regardless of interdental space presence. The result indicated that, despite of their submucosal crown margins, single implantsupported crowns have soft tissue conditions as good as other implants used for the treatment of the different types of edentulism and a clinician can manipulate interdental papilla height by modifying crown shapes within the limits of not violating total esthetics.

• The Journal of Korean Academy of Prosthodontics
• /
• v.30 no.1
• /
• pp.125-132
• /
• 1992

The purpose of this study was to evaluate the effect of the metal coping design on the fracture resistance of ceramometal crown. The Ni-Cr alloy(Supranium, Krupp Co., German) and Vaccm-fired porcelain powder(Vita VMK 689, Vita Co., Germany) were used in this study. The measurement of fracture resisitance of ceramometal crown was done with Instron Universial Testing Machine(Instro Co., Model no.4201). The obained results were as fellows : 1. The fracture resistance measured at the buccal cusp tip was the highest value in the group that those position of ceramometal junction was 2mm superior to the lingual finshing margin(100.25Kg) and the fracture resistance revealed on order of the group that those position was 2mm buccal to the central groove(51.64Kg). 2. The fracture resistance measured at the central groove was higher value in the group that those position was 2mm lingual to the central groove than in the group that those position was 2mm lingual to the central groove than in the group that those position was 2mm superior to lingual finishing margin(132.48Kg). 3. In all cases, the fracture resistance at the central groove was higher than that at the buccal cusp tip.

• The Korean Journal of Archival Studies
• /
• no.36
• /
• pp.35-67
• /
• 2013

As the office of crown properties expanded to financial structure having jurisdiction over various nation's purse in the Great Han Empire, its official document form has been changed. Unlike the early days, they had used official paper stamped with the words 'the Office of Crown Properties' eliminating 'Department of the Royal Household'. Also, the title on stamp of government position changed to 'Recipient of the Official of Crown Properties'. As the office of crown properties expanded as a great financial structure, it has grown in stature as an independent structure, and it was reflected in official document form. Such change was shown in document distribution system. The recipient of report from each district was the First Lord of Department of the Royal Household until 1897; however, the recipients of reports were mostly the office of Crown Properties from 1899. The Office of Crown Properties could not issue an official order before Aug 1899, since then the Office of Crown Properties had issued official orders to each district. However, the Office of Crown Properties could not handle the document in an equal position to the central organization yet. However, from Sep. 1900, the Office of Crown Properties handle the document with district organizations in equal position to the central organization, and a records office had been established in the Office of Crown Properties. Also, the Office of Crown Properties had handled official documents as an independent organization getting out of belonging organization to the department of Royal Household. Since the records office was established in Sep. 1900, the Office of Crown Properties had written receipt book autonomously. Comparing the receipt books in 1901 to the receipt books in 1905 and 1906, receipt numbers had been appeared from the book in 1905 and the organization in charge of the documents was recorded on some documents. Since no receipt book was found in 1902~1904, it is unknown when receipt number had been started indicating on the book. Seeing that the receipt number on the book of 1905 matched with contents on the receipt stamp, the receipt number has started indicating from around July, 1902; the period the receipt stamp has been started to use. Unlike the receipt stamp, the department in charge was indicated on the receipt book. It is because that the Office of Crown Properties changed writing system. Instead of classifying divisions, the Office of Crown Properties recorded in a book by order to receive, provided serial number, and wrote the department on the bottom of receipt book to classify by department in charge. Since establishment of the records office in Sep. 1900, the Office of Crown Properties had confirmed the receipt of document by stamping 'receipt of the Office of Crown Properties' and made receipt books as the office had started handled documents independently. Also, the Office of Crown Properties changed its system integrating division and recording in one book from the intial system classifying the book by division then receipt number and department in charge were indicated on the book. Also, receipt system has stabilized by stamping the receipt date and number on the received document.

• Journal of Korean Society of Forest Science
• /
• v.83 no.2
• /
• pp.205-210
• /
• 1994

This study was conducted to develop a method of mass production by cutting of superior genotypes of Larix leptolepis and to examine the effects of ortet age, clone, crown position, and an applied plant growth substance upon the rooting of cuttings. Four different ortet ages, 2, 8, 16 and 30 years and three levels of root-promoting substances, indole butyric acid(IBA), at 1000, 2000, and 5000ppm were employed. Greenwood cuttings were taken from mother trees in late July and rooted for three months in rooting medium containing peatmoss : vermiculite : perlite(1 : 1 : 1 by volume). with temperature controlled at $20-25^{\circ}C$, humidity by intermittent misting and light by partial shading in the greenhouse. Cuttings treated with 1000ppm IBA showed highest rooting, with 80%, 71%, 52%, 25% for 2-, 8-, 16-. 30-year-old ortet, respectively. Untreated cuttings showed rooting of 52%, 48%, 36%, 20% for the ortet age of 2, 8, 16, 30 years, respectively. The average number of adventitious roots decreased with increasing ortet age from 2 to 30 years, whereas IBA treatment increased the number of roots in all ages. A variation in rooting among 20 clones tested was observed. The 4 clones, Chungnam 6, and 7 and Chonbuk 1, and 9 showed good rooting of about 67%, while Kangwon 49 showed boor rooting of 40% at 1000ppm IBA treatment. When crown position was compared, cuttings taken from middle crown showed highest rooting of 60%, while cuttings from upper crown showed lowest rooting of 53%.

• Journal of Korean Society of Forest Science
• /
• v.100 no.1
• /
• pp.8-13
• /
• 2011

This study was carried out to investigate the change of photosynthesis, leaf and fruit according to crown layers in Actinidia arguta and hybrid kiwi. Photosynthesis rate (PPFD $1,000{\mu}mol{\cdot}m^{-2}s^{-1}$) were 5.82, 7.11, $9.54{\mu}mol\;CO_2\;m^{-2}s^{-1}$ at lower, middle, and upper position, respectively in 3 layer cultivation type. The length and area of leaves collected from lower position have lager value than upper position. The fruit quality of A. arguta and hybrid kiwifruit increased with increasing crown height. A linear correlation ($R^2=0.72$, 0.89 and 0.98) was shown between fruit weight (Boeun 4, Injea 16 and HM3) and the height of crown layer(layer 1, 2, and 3). From the results, we can suppose that the tree of the upper position of crown layer in the cultivation of A. arguta and hybrid kiwifruit produce high quality fruit due to its high photosynthesis ability.

• Journal of Dental Rehabilitation and Applied Science
• /
• v.35 no.2
• /
• pp.105-112
• /
• 2019

Crown fractures are the most frequent traumatic injuries to permanent teeth and mainly involve the maxillary incisors due to their exposed position in the dental arch. One option for managing crown fractures, when the tooth fragment is present and in good condition, is reattachment of the fragment to its original position. This paper reports on three crown fracture cases in which successful esthetic and functional results were achieved by reattachment of the tooth fragment.

• The Journal of Korean Academy of Prosthodontics
• /
• v.48 no.2
• /
• pp.94-100
• /
• 2010

Purpose: The purpose of this study was to compare the fracture strength of the zirconia ceramic crowns according to tooth position. Material and methods: After 10 metal dies were made for each group, the zirconia ceramic crowns were fabricated using CAD/CAM system ($Lava^{TM}$ All-Ceramic System) and each crown was cemented on each metal die with resin cement (Rely $X^{TM}$ Unicem). The cemented zirconia ceramic crowns mounted on the testing jig were inclined with 30 degrees to the long axis of the tooth and the universal testing machine was used to measure the fracture strength. Results: 1. The fracture strength of the zirconia ceramic crown in the lower 1st molar (2963 N) had the highest and that in the lower central incisor (1035 N) had the lowest. 2. The fracture strength of zirconia ceramic crown was higher than that of the IPS Empress crowns in all tooth position. 3. The fracture mode of the crowns was similar. Most of fracture lines began at the loading area and extended through proximal surface perpendicular to the long axis of the crowns. 4. There were no significant differences on the fracture strength of the zirconia ceramic crowns according to tooth position except in premolar group. Conclusion: Within the limitations of this study, the results suggested that strength of zirconia ceramic crown is satisfactory for clinical use.

• Journal of Technologic Dentistry
• /
• v.27 no.1
• /
• pp.105-113
• /
• 2005

The purpose of this study is to evaluate the effect of loading at three different occlusal surface position of the gold alloy crown on the stress distributions in surrounding bone, utilizing 3-dimensional finite element method. A three dimensional finite element model of an implant with simplified gold alloy crown and supporting bone was developed for this study. A oblique or vertical load of 100 N was applied at the following position at each FE model : 1) center of occlusal surface, 2) a point on the buccal side away from center of occlusal surface (COS) by 2.8mm, 3) a point on the lingual side away from COS by 2.8mm. In the results, Minimum von Mises stresses under vertical load or oblique load of 100N were about 6MPa at the center of occlusal surface and about 40MPa at the point on the buccal side, respectively. From the results we could come to the conclusion that occlusive loading position could be an important factor for establishment of structural safety of supporting bone.