• Journal of the korean academy of Pediatric Dentistry
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• v.31 no.1
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• pp.66-78
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• 2004

The objective of this study was to apply the vibration technique to reduce the viscosity of bonding adhesives and thereby compare the bond strength and resin penetration in enamel and dentin achieved with those gained using the conventional technique and vibration technique. For enamel specimens, thirty teeth were sectioned mesio-distally. Sectioned two parts were assigned to same adhesive system but different treatment(vibration vs. non-vibration). Each specimen was embedded in 1-inch inner diameter PVC pipe with a acrylic resin. The buccal and lingual surfaces were placed so that the tooth and the embedding medium were at the same level. The samples were subsequently polished silicon carbide abrasive papers. Each adhesive system was applied according to its manufacture's instruction. Vibration groups were additionally vibrated for 15 seconds before curing. For dentin specimen, except removing the coronal part and placing occlusal surface at the mold level, the remaining procedures were same as enamel specimen. Resin composite(Z250. 3M. U.S.A.) was condensed on to the prepared surface in two increments using a mold kit(Ultradent Inc., U.S.A.). Each increments was light cured for 40 seconds. After 24 hours in tap water at room temperature, the specimens were thermocycled for 1000cycles. Shear bond strengths were measured with a universal testing machine(Instron 4465, England). To investigate infiltration patterns of adhesive materials, the surface of specimens was examined with scanning electron microscope. The results were as follows: 1. In enamel the mean values of shear bond strengths in vibration groups(group 2, 4, 6) were greater than those of non-vibration group(group 1, 3, 5). The differences were statistically significant except AQ bond group. 2. In dentin, the mean values of shear bond strengths in vibration groups(group 2, 4, 6) were greater than those of non-vibration groups(group 1, 3, 5). But the differences were not statistically significant except One-Up Bond F group. 3. The vibration group showed more mineral loss in enamel and longer resin tag and greater number of lateral branches in dentin under SEM examination.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.3
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• pp.375-382
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• 1986

This study was carried out to obtain the basic information for the clarification of spring growth habits mechanism of naked barleys. The isozyme patterns and activities of peroxidase in the young spike and leaf blade were analyzed during the differentiation and development of young spike. The characteristic differences between the normal and rosetted type were in c and g isozymes in young spike, and in i isozyme in the leaf blade. In the normal type, c and i isozymes disappeared at the stage of spi-kelet differentiation, g isozyme at the stage of flolet differentiation. But, in the rosetted type, those three isozymes remained in dark stained condition until the time of final sampling. Especially, those three isozymes were higher in the rosetted type than those in the normal type even at the stage of bract differentiation(BDS), just prior to the reproductive stage. The activities of peroxidase decreased slowly after BDS in the young spike and leaf blade in the normal type, While, in the rosetted type, increased linearly, and the degree of increasing was remarkable in the young spike. It was interesting that the degree of activities in young spike was higher in the rosetted type than that in the normal type even at BDS. From the above results, the remarkable differences of the isozyme patterns and activities at BDS between the normal and rosetted type were considered to be the physiological expression of the varieties concerned with the degree of spring growth habits.

• Journal of the Korean Recycled Construction Resources Institute
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• v.4 no.4
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• pp.117-124
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• 2009

The purpose of the study was to improve quality of high volume fly ash concrete. The study evaluated on the possibility of early quality improvement of high volume fly ash concrete with early strength gain admixture ('GA' below) developed by the preceding research. The study regarded applying naphthalene admixture ('NA' below) to mix proportion substituting FA 15 % to be plain. In the event of substituting FA 20, 25 and 30 %, the study compared engineering properties of concrete with plain by applying GA. Because of features of fresh concrete, fluidity falls down when GA is applied. Therefore, its use amount shall be increased. Only, in W/B 60 %, it was beneficial since slump loss was reduced about 35~70 mm than plain. The study could see that AE use should be increased proportionally since air content was reduced by coming from AE absorption operation of unburned coal content included in FA according to an increase in the amount of FA use. Reduction effect of bleeding could be anticipated since the amount of bleeding appeared at least in FA 20 %. Because of hardened concrete, time of setting appeared in the same level as plain when GA was applied. Therefore, it is judged that delay of setting can be reduced. In compressive strength, the study could check the same strength development as plain when GA was applied, having nothing to do with W/B and curing temperature. However, it is thought that we shall pay attention to GA use in the event of FA 30 % substitution. Freezing and melting resistance had less early value than plain. However, it is judged that there will be no problem of frost resistance since there is no a large difference between freezing and melting resistance and plain in overall. In accelerated neutralization, it was analyzed that a problem of weakening in neutralization appointed as a demerit when FA was applied in mass in proportion with GA use could be settled to some extent.

• Journal of Animal Environmental Science
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• v.17 no.2
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• pp.131-138
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• 2011

This study was carried out to investigate on the composting characteristics variation accoding to air supply capacity in Pig manure. The composting of pig manure is economical and efficiently process. The fermented compost was added in pig manure mixed with sawdust was composting reators. Air supply capacity levels of fermented compost on the pig manure mixed with sawdust were regulated at 50, 100, 150 and 200$\ell/m^3$/min. respectively. The obtained results can be followed as bellow; The temperature variations of experimental composting piles during composting for the different of T-1 reach $40^{\circ}C$ in 2 days, T-2, T-3 and T-4 reach $60^{\circ}C$ in 2 days and T-3, T-4 maintained until 8 days. The decreases in water contents per each square meter for the different of T-1 (50 l/$m^3$/min), T-2(100 l/$m^3$/min), T-3(150 l/$m^3$/min) and T-4(200 l/$m^3$/min.), The decreases ratio in water contents was T-1, T-2, T-3 and T-4 were 15.4%, 28.8%, 33.4% and 35.2%. The decreases ratio in weight was T-1, T-2, T-3 and T-4 were 7.6%, 15.6%, 16.8% and 16.9% respectively. The variations of oxygen concentration from composting period in case of oxygen discharge concentration T-1, T-2, T-3 and T-4 were 9 ppm. respectively. Fertilizer components after composting were examined. Nitrogen contents of the T-1, T-2, T-3 and T-4 were 0.45%, 0.44%, 0.42% and 0.44%, and P2O5 contents were T-1, T-2, T-3 and T-4 were 0.37%, 0.41%, 0.42% and 0.44% respectively. Therefore, the compost curing air supply of air volumes at least 150$\ell$/min/min. or more to supply the aerobic composting pig manure normally are judged to be possible.

• Journal of Korean Medical classics
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• v.23 no.2
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• pp.205-223
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• 2010

In Korean Traditional Medicine(abbreviated to K.T.M.), hyperhidrosis and anhidrosis are the targets of the medical treatment. Furthermore sweating appearance is also one of the important symptoms which explain a particular situation of the patient in K.T.M. And at "Sanghanron(傷寒論)" which is a traditional chief clinical bible written by Jang Gi(張機) later Han dynasty(漢代) in China made full use of the various kinds of diaphoresis[汗法] as a main medical treatment with purgation therapy[下法] and emetic therapy[吐法]. So the sweat in itself not only is the disease, but also is one of the symptoms explain a disease pattern. This thesis inquires into "Hwangjenaegyeong(黃帝內經)" referring to sweat which is the origin of recognition to the sweat in K.T.M. Some theses similar to this research had been made progresses and already reported, but most of them have classified the contents into biology, pathology, diagnosis, treatment after the model of western medical theory. In the aspect of comparative studying with other literature and clinic practical using, we found characteristics of referring to sweat in "Hwangjenaegyeong(黃帝內經)". And we classify the characteristics into some categories as follows. 1. There are some terms which make a title including sweat and symbolize the characteristics, for example sweat of soul[魄汗], sweat of death[絶汗], sweat of streaming[灌汗], sweat of weakness[白汗], sweat of sleep[寢汗], sweat of bright and heat[炅汗], sweat of kidney[腎汗], sweat of escaping[漉汗], cold sweat[寒汗], sweat on the head[頭汗], hyperhidrosis[多汗], heavy sweat[大汗]. But there aren't spontaneous sweat[自汗] or sweat like a thief[盜汗] which are the normal terms referring to sweat in history of K.T.M. And there are several descriptions about sweat appearance such as sweating in half of body[汗出偏沮], sweating in the rear end and thigh and knee[汗出尻陰股膝], hyperhidrosis in the neck and aversion to wind[頸多汗惡風], hyperhidrosis in the head and face and aversion to wind[頭面多汗惡風], cannot stopping the sweating under head[頭以下汗出不可止], make a person sweat to one's feet[令汗出至足], sweating like escaping[漯漯然汗出], sweating like soaking[汗出如浴], sweating become moist[汗出溱溱], hardly escaping sweat[汗大泄], escaping sweating[漉漉之汗], sweat moisten the pores [汗濡玄府], ceaseless sweating like pouring[汗注不休] sweating like pouring and vexation[汗注煩心], damp with sweat[汗汗然], sweating spontaneously[汗且自出], removal of fever with sweat drying[熱去汗稀]. That can be divided into sweat region and sweat form. 2. There are detailed explanations of the principle of perspirations caused by hot weather, hot food, hard working and meeting damp pathogen. 3. There are some explanations of the principle of removing fever due to the excessive heat from internal and external body through sweating by replenishing the body fluid. And many descriptions about overcoming the febrile disease by dropping temperature through sweating and many diaphoresis for curing. 4. There are some descriptions about five Jang organs perspirations and attachment of five mucous body fluid to five Jang organs. 5. There are pathogenic progresses after sweating affected by the Six Atmospheric Influences and water. And detailed explanations of disease mechanism a sweat leading to another disease. 6. There are descriptions about various sweat absent situations.

• Journal of Conservation Science
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• v.32 no.4
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• pp.471-490
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• 2016

This study investigated provenance of raw materials and making technique of lime-based materials used in the tomb barriers of the Yesan Mokri tombs from Joseon dynasty on the basis of analysis to material characteristics and physical properties. In the barrier materials, dry density and porosity are the highest value ($1.82g/cm^3$) and the lowest value (25.20%) in the south wall of No. 1 tomb, respectively. Dry density and porosity are inversely proportional in all barrier materials, but unconfined compressive strength, which is the highest value of $182.36kg/cm^2$ in the No. 2 tomb, does not show an interrelation with porosity and density. Mineral components in the lime-soil mixtures of the tomb barrier are mainly quartz, feldspar, mica and calcite about 200 to $600{\mu}m$ size with yellowish brown matrix. Hydrotalcite and portlandite are detected in the lime mixture, and kaolinite in the soils. The lime materials of the tomb barrier occurred in large quantities weight loss and variable endothermic peaks caused by decarbonization reaction of $CaCO_3$ in the range from 600 to $800^{\circ}C$ in thermal analysis. Making temperature of lime for the tomb barrier is presumed approximately about $800^{\circ}C$ based on the occurrences, compositions and thermal analysis. The tomb barriers are revealed to very wide composition ranges of major elements and loss-on-ignition (22.5 to 33.6 wt.%) owing to mixture of the three materials (lime, sand and clay). It is interpreted that low quality construction technique was applied as the limes are very heterogeneous mixture with aggregates, and curing of the lime was poorly processed in the tomb barriers. Possible limestone sources are distributed in many areas around the Mokri site where limestone conformation and quarries for commercial production are found within Yesan and Hongseong areas. Therefore, we estimated that raw materials were possibly supplied from the local mines near the Mokri site.

• Journal of Animal Science and Technology
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• v.50 no.3
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• pp.391-400
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• 2008

Odor management is significantly concerned with sustainable livestock production because odor nuisance is a primary cause for complaint to neighbors. This study was conducted to measure the concentration of odorous compounds, odor intensity, and odor offensiveness at unit process in animal waste treatment facility combined composting and methane fermentation process by an instrumental analysis and direct olfactory method. Ammonia, sulfur-containing compounds, and volatile fatty acid were analyzed at each process units and boundary area in summer and winter, respectively. Higher concentration of odorants occurred in the summer than in the winter due to high ambient temperature. The maximum concentration of odorants was detected in composting pile when mixed manure was being turned followed by inlet, curing, outlet, and screen & packing process. Highest concentration of detected odorous compounds was ammonia ranging from 3.4 to 224.7 ppm. Among the sulfur-containing compounds measured, hydrogen sulfide was a maximum level of 2.3 ppm and most of them exceeded reported odor detection thresholds. Acetic acid was the largest proportion of VFA generated, reaching a maximum of 51 to 89%, followed by propionic and butyric acid at 1.9 to 35% and 1.8 to 15%, respectively. Malodor assessment by a human panel appeared a similar tendency in instrumental analysis data. Odor quotient for predicting major odor-causing compounds was calculated by dividing concentrations measured in process units by odor detection thresholds. In the composting process, hydrogen sulfide, ammonia, dimethyl sulfide, and methyl mercaptan were deeply associated with odor-causing compounds, while the major malodor compounds in the inlet process were methyl mercaptan, hydrogen sulfide, and butyric acid.

• Restorative Dentistry and Endodontics
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• v.34 no.4
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• pp.333-339
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• 2009

This study was done to determine if there is any difference in microleakage between experimental composite resins, in which various proportions of three component photoinitiators (Camphoroquinone, OPPI, Amine) were included. Four kinds of experimental composite resin were made by mixing 3.2% silanated barium glass (78 wt.%, average size; 1 ${\mu}m$) with each monomer system including variously proportioned photoinitiator systems used for photoinitiating BisGMA/BisEMA/TEGDMA monomer blend (37.5:37.5:25 wt.%). The weight percentage of each component were as follows (in sequence Camphoroquinone, OPPI, Amine): Group A - 0.5%, 0%, 1% / Group B - 2%, 0.2%, 2% / Group C - 0.2%, 1%, 0.2% / Group D - 1%, 1%, 2%. Each composite resin was used as a filling material for round class V cavities (diameter: 2/3 of mesiodistal width; depth: 1.5 mm) made on extracted human premolars and they were polymerized using curing light unit (XL 2500, 3M ESPE) for 40 s with an intensity of 600 mW/$cm^2$. Teeth were thermocycled fivehundred times between $50^{\circ}C$and $550^{\circ}C$for 30s at each temperature. Electrical conductivity (${\mu}A$) was recorded two times (just after thermocycling and after three-month storage in saline solution) by electrochemical method. Microleakage scores of each group according to evaluation time were as follows [Group: at first record / at second record; unit (${\mu}A$)]: A: 3.80 (0.69) / 13.22 (4.48), B: 3.42 (1.33) / 18.84 (5.53), C: 4.18 (2.55) / 28.08 (7.75), D: 4.12 (1.86) / 7.41 (3.41). Just after thermocycling, there was no difference in microleakage between groups, however, group C showed the largest score after three-month storage. Although there seems to be no difference in microleakage between groups just after thermocycling, composite resin with highly concentrated initiation system or classical design (Camphoroquinone and Amine system) would be more desirable for minimizing microleakage after three-month storage.

• The Journal of Korean Academy of Prosthodontics
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• v.59 no.1
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• pp.18-26
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• 2021

Purpose: Generally, patients are noticed to store denture in water when removed from the mouth. However, few studies have reported the advantage of volumetric change in underwater storage over dry storage. To be a reference in defining the proper denture storage method, this study aims to evaluate the volumetric change and dimensional deformation in case of underwater and dry storage. Materials and methods: Definitive casts were scanned by a model scanner, and denture bases were designed with computer-aided design (CAD) software. Twelve denture bases (upper 6, lower 6) were printed with 3D printer. Printed denture bases were invested and flasked with heat-curing method. 6 upper and 6 lower dentures were divided into group A and B, and each group contains 3 upper and 3 lower dentures. Group A was stored dry at room temperature, group B was stored underwater. Group B was scanned at every 24 hours for 28 days and scanned data was saved as stereolithography (SLA) file. These SLA files were analyzed to measure the difference in volumetric change of a month and Kruskal-Wallis test were used for statistical analysis. Best-fit algorithm was used to overlap and 3-dimensional color-coded map was used to observe the changing pattern of impression surface. Results: No significant difference was found in volumetric changes regardless of the storage methods. In dry-stored denture base, significant changes were found in the palate of upper jaw and posterior lingual border of lower jaw in direction away from the underlying tissue, maxillary tuberosity of upper jaw and retromolar pad area of lower jaw in direction towards the underlying tissue. Conclusion: Storing the denture underwater shows less volumetric change of impression surface than storing in the dry air.

• Journal of Animal Science and Technology
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• v.46 no.2
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• pp.261-272
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• 2004

This study was conducted to investigate indices affecting composts maturity for swine manure compost produced in a commercial composting facility with air-forced from the bottom. The composting was made of swine manure mixed with puffing rice hull(6: 4) and turned by escalating agitator twice a day. Composting samples were collected periodically during a 45-d composting cycle at that system, showing that indices of Ammonium-N to Nitrate-N ratio were sensitive indicators of composting quality. Pile temperature maintained more than 62$^{\circ}C$ and water contents decreased about 20% for 25days of composting. A great variety and high numbers of aerobic thermophilic heterotropic microbes playing critical roles in stability of composts have been examined in the final composts, sbowing that they were detected $10^8$ to $10^{10}$ $CFUg^{-1}$ in mesophilic bacteria, $10^3$ - $10^4$ in fungi and $10^6$ - $10^8$ in actinomycetes, respectively. The results of this study for detennining a factor affecting compost stability evaluations based on composting steps were as follows; 1. Ammonium-N concentrations were highest at the beginning of composting, reaching approximately 421mg/kg. However Ammonium-N concentrations were lower during curing, reaching approximately l04mg/kg just after 45 day. The ratio between $NH_4-N$ and $NO_3-N$ was above II at the beginning of composting and less than 2 at the final step(45 day). 2. Seed germination Index was dependent upon the compost phytotoxicity and its nutrition. The phytotocity caused the GI to low during the period of active composting(till 25 days of composting time) depending on the value of the undiluted. After 25 days of composting time, the GI was dependent upon compost nutrition. The Gennination index of the final step was calculated at over 80 without regard to treatments. 3. E4: E6 ratio in humic acid of composts was correlatively decreased from 8.86 to 6.76 during the period of active composting. After 25 days of composting time, the E4: E6 was consistently decreased from 6.76 to 4.67($r^2$ of total composting period was 0.95). 4. Water soluble carbon had a tendency to increase from 0.54% to 0.78%during the period of active composting. After 25 days of composting time, it was consistently decreased from 0.78% to 0.42%. Water soluble nitrogen increased from 0.22% to 0.32% during the period of 15 days after initial composting while decreased from 0.32% to 0.21% after 15days of composting. In consequence, the correlation coefficient($r^2$) between water soluble carbon and water soluble nitrogen was 0.12 during the period of active composting mule was 0.50 after 25 days of composting time