• The Journal of Korean Academy of Prosthodontics
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• v.46 no.5
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• pp.511-519
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• 2008

Statement of problem: An incompatibility between the initiator systems of self-curing composite resins and light-curing adhesives was supposed recently. Purpose: The purpose of the study was to evaluate the influence of activators for self/dual bonding on dentin shear bonding strengths. Material and methods: Fifty human molars were divided into 5 groups. A flat dentin surface was created for each tooth. A self-curing composite resin (Luxacore) was bonded with the following adhesives (n = 10); One-Step, Prime&Bond NT, AdheSE, Prime&Bond NT and AdheSE were also used in combination with activators. Shear bond strengths were measured after 24 hours of water storage. The specimens were loaded in shear in the Instron until failure at a 1 mm/min crosshead speed. Data were compared using one-way ANOVA and Tukey HSD test (${\alpha}$= 0.05). Results: The dentin adhesive systems in order of decreasing median bond strength were One-Step > Prime&Bond NT with activator, AdheSE with activator > Prime&Bond NT, AdheSE. Among adhesives, One-Step had the highest bond strength. Prime&Bond NT with activator had higher bond strengths than Prime&Bond NT that was used alone, and so was AdheSE. Conclusion: Shear bond strengths were increased in Prime&Bond NT and AdheSE when these were used with activators comparing used without activators. But using activators was not effective clinically comparing One-Step.

• The Journal of Korean Academy of Prosthodontics
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• v.46 no.5
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• pp.535-543
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• 2008

Purpose: The objective of this study was to compare the bonding characteristics of a new self-adhesive resin cement to dentin, which does not require bonding and conditioning procedure of the tooth surface, and conventional resin cement. The effect of phosphoric acid etching prior to application of self-adhesive resin cement on the shear bond strength was also evaluated. Material and methods: Fortyfive non-carious human adult molars extracted within 6 months were embedded in chemically cured acrylic resin. The teeth were ground with a series of SiC-papers ending with 800 grit until the flat dentin surfaces of the teeth were exposed. The teeth were randomly divided into 3 experimental groups. In group 1, self-adhesive resin cement, RelyX Unicem (3M ESPE, Seefeld, Germany) was bonded without any conditioning of teeth. In group 2, RelyX Unicem was bonded to teeth after phosphoric acid etching. For group 3, Syntac Primer (Ivoclar Vivadent AG, Schaan, Liechtenstein) was applied to the teeth before Syntac adhesive (Ivoclar Vivadent AG, Schaan, Liechtenstein) and Helibond (Ivoclar Vivadent AG, Schaan, Liechtenstein) followed by conventional resin cement, Variolink II (Ivoclar Vivadent AG, Schaan, Liechtenstein). To make a shear bond strength test model, a plastic tuble (3 mm diameter, 3 mm height) was applied to the dentin surfaces at a right angle and filled it with respective resin cement, and light-polymerized for 40 seconds. All the specimens were stored in distilled water at $37^{\circ}C$ for 24 hours before test. Universal Testing Machine (Z020, Zwick, Ulm, Germany) at a cross head speed of 1 mm/min was used to evaluate the shear bond strength. The failure sites were inspected under a magnifier and Scanning Electron Microscope. The data was analyzed with One way ANOVA and Scheffe test at ${\alpha}$= 0.05. Results: (1) The shear bond strengths to dentin of RelyX Unicem was not significantly different from those of Variolink II/Syntac. (2) Phosphoric acid etching lowered the shear bond strength of RelyX Unicem significantly. (3) Most of RelyX Unicem and Variolink II showed mixed fractures, while all the specimens of RelyX Unicem with phosphoric acid etching demonstrated adhesive failure between dentin and resin cement. Conclusion: Shear bond strength to dentin of self-adhesive resin cement is not significantly different from conventional resin cement, and phosphoric acid etching decrease the shear bond strength to dentin of self-adhesive resin cement.

• Journal of the korean academy of Pediatric Dentistry
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• v.29 no.4
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• pp.632-640
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• 2002

The objective of the study was to apply the vibration technique to reduce the viscosity of bonding adhesives and thereby compare the bond strength and resin penetration into dentinal tubules achieved with those gained using the conventional technique. Eighty-eight noncarious extracted human permanent molar teeth were sectioned to remove the coronal enamel and were embedded in 1-inch PVC pipe with acrylic resin. The occlusal surfaces were placed so that the tooth and the embedding medium were at the same level to form one flat surface, and the samples were subsequently polished with silicon carbide abrasive papers. The samples were randomly assigned to 4 groups(n=22). On Group 1 and 2, Single Bond(3M-ESPE, St. Paul, USA) was used, and on Group 3 and 4, One-Step(Bisco Inc., Schaumburg, USA) was used, and each was applied according to its manufacturer's instructions. For Group 2 and Group 4, vibration was applied with ultrasonic scaler for 10 seconds, and the adhesive was light-cured for 10 seconds. Resin composite was condensed on to the prepared surface in two increments using a mold kit(Ultradent Products Inc., USA) and each was light-cured for 40 seconds. After 24 hours in tap water at room temperature the specimens were thermocycled, and shear bond strengths were measured with a universal testing machine(Instron 4465, Canton, USA). To investigate infiltration patterns of the adhesive materials, the surface of specimen was examined with scanning electron microscope. The results were as follows. 1. The shear bond strengths of vibration groups(Group 2, Group 4) were significantly greater than those of the non-vibration groups(Group 1, Group 3)(p<0.05). 2. The shear bond strengths of Single Bond and One-Step were not significantly different (p>0.05). 3. The vibration groups showed greater number of resin tags in tubules and lateral branches under SEM.

• Journal of the korean academy of Pediatric Dentistry
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• v.30 no.2
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• pp.272-285
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• 2003

This study was conducted to observe the microscopic structures of cavities formed after ablation of primary teeth, permanent teeth, enamel and dentin in using a bur and cavities formed after ablation using laser and the following results were obtained after comparing the effects of ablation. Using a #330 bur and Er:YAG laser irradiated at 150 mJ, 200 mJ, 250 mJ and 300 mJ all at the frequency of 5 Hz, 1 mm enamel and dentin samples were ablated and the ablation time was measured. In order to measure the surfaces ablated, 5 each of primary teeth and permanent teeth were ablated using a #330 bur and Er:YAG laser at 150 mJ, 200 mJ, 250 mJ and 300 mJ for 1 sec and the cross section and vertical section were observed. The following results were obtained : 1. Cutting time of Er:YAG laser was longer than that of conventinal high-speed bur regardless of teeth type. 2. Cutting on enamel, Cutting time of conventional high-speed bur in deciduous teeth was longer than in permanent teeth(P<0.05). But Er:YAG laser was not showed any difference between the deciduous and permanent teeth(P>0.05). 3. Cutting on dentin, Cutting time of conventional high-speed bur in permanent teeth was longer than deciduous teeth. Er:YAG laser of 150 mJ, 5 Hz in permanent teeth was longer than in deciduous teeth(p<0.05). But laser of other power did not showed mean difference. 4. The cavity surface treated with the convetional high-speed bur revealed a relatively flat appearance, almost covered with a debris-like smear layer. Cavity wall showed striped appearance because of blade of bur. 5. The cavity surface treated by the Er:YAG laser system was irregular or rough surface with the absence charring, carbonization, or cracking of the dentin. In addition, there was an absence of a smear layer. Cavity floor was round and relatively smooth. According to these results, cutting time of Er:YAG laser was almostly same in permanent and deciduous teeth, but more effective in dentin than enamel. Cutting the sample, Er:YAG laser was needed more time than conventional bur. But SEM findings suggested that laser device produced favorable surface characteristic(i.e, no smear layer, irregular surface, cracking).

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.11
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• pp.1615-1634
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• 2004

A review was undertaken to obtain information on the sustainability of pig free-range production systems including the management, performance and health of pigs in the system. Modern outdoor rearing systems requires simple portable and flexible housing with low cost fencing. Local pig breeds and outdoor-adapted breeds for certain environment are generally more suitable for free-range systems. Free-range farms should be located in a low rainfall area and paddocks should be relatively flat, with light topsoil overlying free-draining subsoil with the absence of sharp stones that can cause foot damage. Huts or shelters are crucial for protecting pigs from direct sun burn and heat stress, especially when shade from trees and other facilities is not available. Pigs commonly graze on strip pastures and are rotated between paddocks. The zones of thermal comfort for the sow and piglet differ markedly; between 12-22$^{\circ}C$ for the sow and 30-37$^{\circ}C$ for piglets. Offering wallows for free-range pigs meets their behavioural requirements, and also overcomes the effects of high ambient temperatures on feed intake. Pigs can increase their evaporative heat loss via an increase in the proportion of wet skin by using a wallow, or through water drips and spray. Mud from wallows can also coat the skin of pigs, preventing sunburn. Under grazing conditions, it is difficult to control the fibre intake of pigs although a high energy, low fibre diet can be used. In some countries outdoor sows are fitted with nose rings to prevent them from uprooting the grass. This reduces nutrient leaching of the land due to less rooting. In general, free-range pigs have a higher mortality compared to intensively housed pigs. Many factors can contribute to the death of the piglet including crushing, disease, heat stress and poor nutrition. With successful management, free-range pigs can have similar production to door pigs, although the growth rate of the litters is affected by season. Piglets grow quicker indoors during the cold season compared to outdoor systems. Pigs reared outdoors show calmer behaviour. Aggressive interactions during feeding are lower compared to indoor pigs while outdoor sows are more active than indoor sows. Outdoor pigs have a higher parasite burden, which increases the nutrient requirement for maintenance and reduces their feed utilization efficiency. Parasite infections in free-range pigs also risks the image of free-range pork as a clean and safe product. Diseases can be controlled to a certain degree by grazing management. Frequent rotation is required although most farmers are keeping their pigs for a longer period before rotating. The concept of using pasture species to minimise nematode infections in grazing pigs looks promising. Plants that can be grown locally and used as part of the normal feeding regime are most likely to be acceptable to farmers, particularly organic farmers. However, one of the key concerns from the public for free-range pig production system is the impact on the environment. In the past, the pigs were held in the same paddock at a high stocking rate, which resulted in damage to the vegetation, nutrient loading in the soil, nitrate leaching and gas emission. To avoid this, outdoor pigs should be integrated in the cropping pasture system, the stock should be mobile and stocking rate related to the amount of feed given to the animals.

• Journal of the Korean Society of Costume
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• v.7
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• pp.5-19
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• 1983

Sacredotal robe(法服) means full court dress. We can't know about the shape of sacredotal robe before Dae-Han Empire(大韓帝國) since there are no remains of it. The study of sacredotal robe for queen have also been made centering around the socredotal robe granted from Ming(明) dynasty and the system of Juck-Eui(翟衣) in Dae-Han Empire. In this thesis I tried to study about the sacredotal robe for queen from King Gong-Min(恭愍王) of Koryeo(高麗) dynasty to the close the Cho-Sun(朝鮮) dynasty by investigating the Literature of Cho-sun Dynasty Chronicles(朝鮮王朝實錄), Ga Rae Do Gam Eui Gue(嘉禮都監儀軌), Sang Bang Jung Rae(尙方定例), Gook Hon Jung Rae(國婚定例), Sok-Orae Eui-Bo(續五禮儀補), and Dae Myung Whe Jeon(大明會典). The first documents on sacredotal robe for queen is regarded as that in the period of King Gong Min., which says that Chil Whee Gu Bong Gwan and Juck Eui of the 9th grade had been given from Ming dynasty. The sacredotal robe for queen in Chosun had been granted from Ming dynasty since the 3th years of King Tae-Jo(太祖) to the 3th years of King In-Jo(仁祖). They were Ju Chui Chil Juck Gwan, red Dae Sam(大衫), Bae Ja(褙子) embroidered with. pheasants on blue silk, and ivory flat baton (笏), which belonged to the court dress for the first class of court lady. When Qing(淸) dynasty succeeded to Ming dynasty, Cho-sun adopted the system of luck Eui which had it's origin in the system of Ming, denying to comply with Chung. But as a matter of fact, the system of sacredotal robe for queen actually used was one which were different from the dress system of Ming and converted into our national ways. In the latter period. of Cho-sun, the system of Bae Ja or Juck Eui were used together until the period of King Young Jo(英祖), and the system of Juck Eui which was written in Gook Hon Jung Rae was continually used from King Young Jo to the close of Cho-sun. It was composed of Juck Eui, Beol Eui(別衣), Nae Eui(內衣), Pe Sool(蔽膝), Dae Dae(大帶), HaPi, Sang(裳), Ok Dae(玉帶), Pae Ok(佩玉), Gue(圭), Mal(襪), Suk, and Myun sa(面紗), The headdress was used in our own ways, not complying with Juck Gwan(翟冠). The color of Juck Eui was red for queen, deep blue for the consort of the crown prince. The color of Juck Eui in DaHan Empire was deep blue, different from that of Juck Eui in Cho-sun. Bo(補) for queen wus embroidered with dragon with five claws and the one for the consort of crown prince with dragon with four claws. The back length of Juck Eui was longer than front about 28cm (1尺), and the front opening was straight down. 51 motifs of a brace of pheasants which were similiar to Bong(鳳) were embroidered on Juck Eui for queen. But we can't find out whether there 31 or 51 on Juck Eui for the consort of the crown prince. The system shows independant aspects, because there are Bo, Myun Sa, Sang, Ha Pi, Beol Eui, and Nae Eui which were not found in the system of Ming. As mentioned above, I have studied on the sacredotal robe for queen. But we can't guess the detail of sacredotal robe for queen, because there are no remains at all. Therefore I expect more study on this.

• Journal of the Korean Institute of Landscape Architecture
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• v.40 no.6
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• pp.112-126
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• 2012

The theme is to analyze the time-series changes of design elements on golf courses and golf country club and its factors influencing to the changes with regard to 81-membership country club located in the Capital Area of Seoul, created in the periods from 1964 until 2011. The research methods is to analyze the time-series changes of environmental factors influencing to the changes of the elements on the golf course by book review, and to compare and speculate the results of the analysis on the environmental factors with the time-series changes on the golf course elements of statistical analysis as like regression analysis. The research results were as follows. The first, the environmental factors influencing to the change of golf course elements were analyzed as the five elements of the golf-related policies and regulations, the economy, the numbers of golfers, PGA and KPGA golf tournaments, the golf instruments. The second, the type and scale of the location of the golf course were showing trends of transformation from flat ground to mountainous one and from small scale to large one. The third, it was analyzed that he golf course elements as like the sizes, length, numbers of golf course elements as like fairway, green, bunker, teeing ground and pond were influenced by the law and regulation, the increase of amateur golfers, the promotion of techniques of golfers, the increase of the chance of foreign course designer's involvement to domestic market through the opening of PGA and KPGA tournaments etc. The fourth, the promotion of golf instruments and the flying distance were the factors influencing to the numbers of bunker, the lengths of holes. The fifth, it was revealed that the trends of increase of sizes of ponds influenced by enacting environmenal friendly laws and regulations, considering of landscaping, reflecting of design trends followed by the opening of PGA tournaments. Finally, it was proposed that the further research would be introduced with regard to the qualitative analysis onto the changes and influential factors of golf course design.

• Journal of the Korean Institute of Landscape Architecture
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• v.40 no.6
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• pp.23-34
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• 2012

This Study is about the "Comprehensive Landscape Improvement Plan for Gu-ryoung Seaside Village that was one of most exhibited projects for developing sea villages." The formulations of the plan were supervised by the Ministry of Land, Transport, and Maritime Affairs and were executed by the Goheung Country. Rather than proposing renovations for the landscape, this study maintains the existing order and attempts to examine the plan by scrutinizing the vernacular design language of the landscape. In the study, community members had the opportunity to express their opinions and ideas about the community through workshops composed of community participation programs, and participated in the decision-making process through consultation meetings. The conclusion of this study was relevant to the activities of the committee on landscape improvement. The Comprehensive Landscape Improvement Plan has three objectives: (1) resorting and modifying the natural landscape, (2) restructuring the roadways, and (3) modifying key spaces. In the end, the role of Gu-ryong Mountain as a background of the landscape was focused on tree planting drives that were undertaken, and accessibility to the sea front was improved. Second, in restructuring the roadways, rough roads were restored and unconnected roads were connected to ensure a network of roads along the sea front, inner roads in the village, roads at the Fringes Mountains, and stone roads on the mud flat. In addition, roads were named according to the character of the landscape and signs were installed. Finally, the existing key spaces, in which community members came together, were restored and new key spaces were created for the outdoor activities of the inhabitants and the diverse experience of visitors. A guideline was also created to regulate private areas such as roofs, walls, fences of residential buildings, and private container boxes and fishing gear along the sea front. The strength of this study is that it is seeking to determine the greatest potential of the landscape and set the plan by examining the lives of community members. Some problems were found during the development of this study. Further, there were problems in the community's understanding as elaborated below. First is the gap between community members' awareness and practice. Even though they were aware of the problems with the village landscape, they hesitated to implement improvements. Second, community members have misunderstandings about the landscape the improvement plan. The local government and the residents have understood this plan as a development project; for example, new building construction or the extension of roads. Third, residents are not aware that continuous attention and improvements are required for the upkeep of the landscape in the sea village. The plan to improve the landscape should promote a balance between making the area as a tourist attraction and maintaining the lives and cultural activities, because the sea village system incorporates settlements, economy, and culture.

• Journal of Wetlands Research
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• v.19 no.1
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• pp.172-179
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• 2017

The purpose of this study is to analyze the current original habitat and to conserve the narrow-mouthed toad populations. For this study, we used 240 pitfall traps (30 cm height ${\times}$ 20 cm width) to catch the narrow-mouthed toads that inhabit in Myeongji-dong, Gangseo-gu, in Busan metropolitan city from August 2, 2013 to November 7, 2013. We measured the environmental characteristics (soil composition factors, soil moisture, Humidity, soil temperature) for the seven habitat patterns of narrow-mouthed toads based on vegetation types. Main habitats of narrow mouthed toads were flat grassland where grass and false acacia grew and there was wetland all over the place. When analyzing habitats that main habitats of narrow-mouthed toads prefer after selecting representative seven vegetation, it was found that the most narrow-mouthed toads were caught in amur silver grass colony while the least narrow-mouthed toads were caught in bare land. Totally, we caught 846 narrow-mouthed toads over 68 times, and released them into the newly constructed habitat after injection VIE-tag. It seems that the reason for which the least narrow mouthed toads were caught in bare land is that bare land is not suitable for narrow mouthed toads to protect themselves from strong sunlight and to hide themselves from natural enemy. We found that temperature had the greatest influence on activities of narrow mouthed toads and at temperature of less than $15.6^{\circ}C$. We also found that the activities of narrow mouthed toads were remarkably low and then temperature was below $15.6^{\circ}C$. It meant that narrow mouthed toads seemed to go into hibernation. From this research, we could find the prefer habitat after analyzing habitats for the narrow-mouthed toads and could suggest for construction for the better habitat of narrow-mouthed toads.

• Journal of the Mineralogical Society of Korea
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• v.19 no.4 s.50
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• pp.265-275
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• 2006

It is in its infancy to use bacteria as a novel biotechnology for leaching precious and heavy metals from raw materials. The objective of this study was to investigate biogeochemical processes of iron leaching from magnetite reduction by iron-reducing bacteria isolated from intertidal flat sediments, southwestern part of Korea. Microbial leaching experiments were performed using commercial magnetite, Aldrich magnetite, in well-defined mediums with and without bacteria. Water soluble Fe production was determined by ICP analysis of bioleached samples in comparison to uninoculated controls, and the resulting precipitated solids were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The extent of iron leaching from magnetite in the aerobic conditions (Fe = 107 ppm) was higher than that in the anaerobic environments (Fe = 94 ppm). In the anaerobic conditions, Fe(III) in commercial magnetite was also reduced to Fe(II), but no secondary mineral phases were observed. Amorphous iron oxides formed in the medium under aerobic conditions where there was sufficient supply of oxygen from the atmosphere. SEM observation suggests that the reduction process involves dissolution-precipitation mechanisms as opposed to solid state conversion of magnetite to amorphous iron oxides. The ability of bacteria to leach soluble iron and precipitate amorphous iron oxides from crystalline magnetite could have significant implications for biogeochemical processes in sediments where Fe(III) in magnetite plays an important role in the largest pool of electron acceptor as well as the tool as a novel biotechnology for leaching precious and heavy metals from raw materials.