• Restorative Dentistry and Endodontics
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• v.33 no.4
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• pp.405-412
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• 2008

This study was aimed to investigate whether an oxygen inhibition layer (OIL) is essential for the interfacial bonding between resin composite layers or not. A composite (Z-250, 3M ESPE) was filled in two layers using two aluminum plate molds with a hole of 3.7 mm diameter. The surface of first layer of cured composite was prepared by one of five methods as followings, thereafter second layer of composite was filled and cured: Group 1 - OIL is allowed to remain on the surface of cured composite; Group 2 - OIL was removed by rubbing with acetone-soaked cotton; Group 3 - formation of the OIL was inhibited using a Mylar strip; Group 4 - OIL was covered with glycerin and light-cured; Group 5 (control) - composite was bulk-filled in a layer. The interfacial shear bond strength between two layers was tested and the fracture modes were observed. To investigate the propagation of polymerization reaction from active area having a photo-initiator to inactive area without the initiator, a flowable composite (Aelite Flow) or an adhesive resin (Adhesive of ScotchBond Multipurpose) was placed over an experimental composite (Exp_Com) which does not include a photoinitiator and light-cured. After sectioning the specimen, the cured thickness of the Exp_Com was measured. The bond strength of group 2, 3 and 4 did not show statistically significant difference with group 1. Groups 3 and 4 were not statistically significant different with control group 5. The cured thicknesses of Exp_Com under the flowable resin and adhesive resin were 20.95 (0.90) urn and 42.13 (2.09), respectively.

• FLOWER RESEARCH JOURNAL
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• v.19 no.2
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• pp.81-88
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• 2011

Effect of concentrations of different plant growth retardants (PGRs) supplied to a recirculated nutrient solution in an ebb and flow system on the growth and development of potted Spathiphyllum 'Top-Pin' and 'Mini' was examined. Plants were planted in 10 cm diameter plastic pots filled with a mixture of peat moss and perlite (1 : 1, v/v) on 30 June 2005 and grown until 23 Sep. 2005. In a closed ebb and flow system, 50, 200, 350, $500mg{\cdot}L^{-1}$ daminozide (B-9), 10, 40, 70, $100mg{\cdot}L^{-1}$ paclobutrazol (Boundy), 5, 15, 25, $35mg{\cdot}L^{-1}$ ethephon (Florel), and 1, 4, 7, $10mg{\cdot}L^{-1}$ uniconazole (Sumagic) were supplemented to a nutrient solution at the initiation of experiment. On every irrigation, the nutrient solution containing PGRs was supplied at a 2 cm depth and kept for 15-20 minutes. The surplus nutrient solution was drained back into the tank for next irrigations. Paclobutrazol gave the most pronounced effect in inhibition of stretchiness. The greatest reduction of leaf length, fresh and dry weights of shoot, and elevated chlorophyll content were recorded in Spathiphyllum, with increasing paclobutrazol concentration. Daminozide concentration greater than $200mg{\cdot}L^{-1}$ resulted in minor stunting. The lowest concentration ($1mg{\cdot}L^{-1}$) of uniconazole showed greater leaf length, leaf width, and leaf petiole length than the control ($0mg{\cdot}L^{-1}$). Uniconazole concentration greater than $1mg{\cdot}L^{-1}$ resulted in similar plant growth as the plant in the control ($0mg{\cdot}L^{-1}$). High concentration ($35mg{\cdot}L^{-1}$) of ethephon resulted in the shortest leaf length, and the greatest chlorophyll content. Inhibition of stretchiness was observed even in the lowest concentration treatments. Among the PGRs, paclobutrazol was most effective in suppressing plant stretchiness. In both cultivars, ethephon and paclobutrazol, but not daminozide and uniconazole, significantly inhibited stretchiness. The results suggested that plant growth retardants (ethephon or paclobutrazol) selected in this study may be used as the most effective agents for inhibition of stretchiness in Spathiphyllum.

• Journal of Bio-Environment Control
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• v.28 no.4
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• pp.454-460
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• 2019

The purpose of this study is to analyze the distribution characteristics of mist spray particle size by devising a rotary mist spraying device to develop the evaporative salt water desalination system. The rotary mist spraying device was consisted of a BLDC sirocco fan, a spinning fan, a fan fixed shaft and a salt water supply device etc. In this study we analyzed the characteristics of spray particle size and distribution according to the variation of sirocco fan surface roughness(Ra, ${\mu}m$), revolutions(rpm) and salt water flow rate(mL/min). When sirocco fan surface roughness(Ra) was in the range of $0.27{\sim}7.65{\mu}m$, the spray particle size was $0.117{\sim}1.360{\mu}m$. And then more than 90% of spray particles were found to be less than $0.50{\mu}m$. When sirocco fan surface roughness(Ra) was in the range of $12.70{\sim}22.84{\mu}m$, the spray particle size was $2.51{\sim}184.79{\mu}m$ and more than 98% of spray particles were found to be less than $13.59{\mu}m$. To analyze the effect of fan rotation speed on the size and distribution of spray particles, when surface roughness Ra was fixed $0.27{\mu}m$ and fan rotation speed and salt water flow rate was respectively changed at 3,800~5,600 rpm and 2.77~8.28 mL/min, spray particle size was $0.314{\sim}0.541{\mu}m$. And when salt water flow rate was 9.74 mL/min and fan rotation speed was 3,800~5,200 rpm, spray particle size was in the range of $29.29{\sim}341.46{\mu}m$ and in case of 5,600 rpm more than 98.23% of spray particles were in the range of $2.51{\sim}13.59{\mu}m$.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.25 no.4
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• pp.281-294
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• 1999

Vasospasm causes microvascular surgery to fail as a main factor in the loss of transferred flap dye to the diminution of blood flow in reconstruction surgery. Although there has been extensive research to resolve the vasospasm problem, no one has reached an ideal solution to date. However, cryotherapy, which is often used for destruction of tumor lesions, is being presented as a new way of releasing vasospasm. After making a histomorphometric measurement on vasodialation during the course of 1, 3 and 7 days, 2 and 4 weeks, and 5 months periods and observing the change of blood vessel in a histologic, immunohistochemical, and scanning electronic microscopic approach, the results were as follows : 1. Vascular inner diameters of the experimental 1 and 3 days groups were measured $476.3{\pm}28.20{\mu}m$, $497.15{\pm}48.79{\mu}m$ respectively showing statistically meaningful vasodilation(P<0.05), which continued by the experiment 4 weeks group. However, in the experimental 5 months group, the vascular inner diameter appeared similar to the control groups. Even though the thickness of smooth muscular layers come out to be thinner in all the experimental groups compared to the control group, it was difficult to find any statistical meaningfulness. In addition, the vascular external diameters of every experimental groups were shown to be longer than the control group. 2. In light microscopic view, severe injury was evident on the smooth muscular layer cell from the experimental 1 day group, started recovering partially from the experimental 7 days group, and was mostly restored in the experimental 4 weeks group and layer of adventitial stripping were nearly recoverd 2 weeks group. 3. The PCNA positive cells of smooth muscular layer were observed from the experimental 7 days group and had a tendency to increase by the experimental 2 weeks group. In the experimental 4 weeks and 5 months group, the number of PCNA possitive cells observed was comparable to the control group. 4. ${\alpha}$-SMA level of smooth muscular layer cells, having been significantly lower than the control group in the severly damaged experimental 1 day group. It was seen to be increased in the experimental 7 days group and turned out to show similar ${\alpha}$-SMA level in 4 weeks to the control group. 5. In the view of SEM, the endothelial cells were destructed and falling off, and also present the appearance of flattening in the experiment 1 day group. The endothelial layer cells started partially recovering from the 7 days group after the freezing injury. On 4 weeks and 5 months, the endothelial cells were fully coverd the damaged area, also it's appearance is similar to control group. In conclusion, the vascular freezing after the removal of adventitia caused damages to smooth muscular layer cells, and brought about vasodilation, which continued by the 4th week. The smooth muscular layer cells started partially reviving from the 7rd day after the damage by vascular freezing, and recovered their similar figure to the control group's 4 weeks later. This was considered the result of cells which surround the damaged blood vessel being influxed into the smooth muscular layers. Therefore, this local freezing injury on the blood vessel was thought to be applied clinically to relieve severe vasospasm which cannot be treated by vasodilation drug, a microvascular surgery.

• Korean Journal of Poultry Science
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• v.43 no.4
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• pp.197-206
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• 2016

This work was carried out to investigate effects of the freezing/thawing method on duck meat kept in a freezer for a month. The meats used were breast muscle collected from Korean native ducks (KND) that were fed for 8 weeks (2.8 kg of live weight). Forty-five samples were used after being frozen in storage for one month and were then divided into 5 treatments (3 replications/treatment, 3 samples/replication). Five treatments (CON, FFFT, FFST, SFFT and SFST) were control groups (CON) and four were experimental groups, using $2{\times}2$ complex factors with two freezing methods (fast freezing, FF, $-50^{\circ}C$ in a deep freezer; slow freezing, SF, $-20^{\circ}C$ in a common freezer) and two thawing methods (fast thawing, FT, 5 h $12^{\circ}C$ with flow water; slow thawing, ST, 24 h $5^{\circ}C$ in a refrigerator). Lightness of KND meat in FF and FT groups was lower than that of control (P<0.05). Yellowness of KND meat of the ST group was higher than that of control (P<0.05). Cooking loss (CL) and water holding capacity (WHC) of KND meat in the control were lower than those of the freezing and thawing groups (P<0.01, P<0.05), but shear force (SF) of the control was higher than that of other groups (P<0.01). Moisture content of the ST group was higher than that of the FT group (P<0.05), and protein content of the FF group was higher than that of control (P<0.05). Stearic acid (C18:0) of the SF group was higher than that of the FF group (P<0.05). Arachidonic acid (C20:4n6) of control was higher than that of the SF and ST groups (P<0.01, P<0.05). Alanine, aspartic acid, glutamic acid, serine, and tyrosine content of the control were lower than that of the freezing and thawing groups (P<0.05). These results show that freezing and thawing methods affect meat color, shear force, cooking loss, and WHC-related water content.

• Journal of Korean Society of Forest Science
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• v.87 no.4
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• pp.519-527
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• 1998

An economic study of vegetation control to increase production of Songyi (Korean name far pine mushroom, matsutake, Tracholoma matsutake (S. Ito & Imai) Sing.) in red pine (Panes densiflora) stands in Korea was undertaken. In Korea, Songyi grows only in red pine stands. Harvest of this mushroom provides a significant income source to rural people in Korea yielding exports of US$20 million to US$80 million per year. However, hypogeous Songyi colonies and the mushroom production are declining, partly because shade tolerant species are succeeding the shade intolerant red pine. Past research says that it is possible to deep Songyi production increasing by controlling under-story vegetation. But few people are wilting to invest in the necessary control. Our analysis found that the economics of vegetation control appear to be quite favorable, showing an internal rate of return (IRR) of 20.7 percent in 15 years. However, positive returns do not occur for at least eight years and even then, the returns may not appear to the landowner to be a result of vegetation control efforts only because the mushroom production has been greatly variable depending on weather conditions. In a sensitivity analysis, it was found that the number of circular mushroom colonies was critically important for the cash flow. Results of this analysis are also sensitive to assumptions about annual growth length(0.16m radial growth=1.0m/circular length growth) of Songyi colony. However, the primary goal of vegetation control should be to keep the young colonies growing. Further research in the behavior of hypogeous Songyi colonies after vegetation control would help to improve our confidence in the results.

• Fisheries and Aquatic Sciences
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• v.8 no.2
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• pp.65-69
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• 2005

We evaluated the effects of the partial dietary replacement of fish meal with squid liver $Meal^{TM}$ on the growth and body composition of juvenile olive flounder Paralichthys olivaceus during the winter season. Twenty-five fish with an initial body weight of 23 g per tank were distributed among 12,250 L flow-through tanks. The experimental diets, which were designated SLM5, SLM1O, and SLM15 diets, were prepared in triplicate along with control diet by replacing 5, 10, and $15\%$ of mackerel fish meal with squid liver $Meal^{TM}$, respectively. The weight gain and specific growth rate of flounder that were fed the control and SLM5 diets did not differ from those of the fish fed the SLM10 diet, but they were significantly (P<0.05) higher than those of the fish fed the SLM15 diet. The feed efficiency ratios for the flounder that were fed the control, SLM5 and SLM10 diets were significantly (P<0.05) higher than for the fish that were fed the SLM15 diet. However, the protein efficiency ratio for the flounder was not significantly affected by the experimental diets. The crude protein, crude lipid and ash content, and blood chemistry of the flounder were not significantly affected by the experimental diets. Therefore, the replacement of up to $10\%$ of dietary fish meal with squid liver $Meal^{TM}$ can be made without a reduction in growth or a deterioration of the feed efficiency of juvenile olive flounder during the winter season.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.4B
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• pp.221-232
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• 2012

In this study, the model enhancing the safety of reservoirs and reducing the downstream flood damage by reservoirs system operation during abnormal flood was developed. Linear programming was used for the optimal reservoirs system operation during an abnormal flood and fuzzy inference system was introduced to solve the uncertainty problem which is included in hydrological factors like inflow, water level and inflow variation of reservoir operation. The linear programming model determined the optimal reservoir system operation rules and could be used in situation where water demands varies rapidly during the abnormal flood events using fuzzy control technique. In this study, the optimal reservoirs system operation for Andong and Imha reservoirs located in the upper basin of Nakdong river was performed in order that the design flood discharge at Andong city would not be exceeded for the design flood of 100 year and PMF(Probable Maximum Flood). And the model that determines the release according to the downstream flow discharge, the reservoir storage, the inflow and the inflow variation of each reservoir was developed using the optimal system operation result and fuzzy control technique. The developed model consisted of 224 fuzzy rules according to the conditions of Andong reservoir, Imha reservoir and Andong city. And the release from each reservoir could be determined when the current data are used as input data through the developed GUI.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.34 no.2
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• pp.627-635
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• 2014

Currently the highest speed limit on the road traffic congestion or because you can not cope with climate change to cause a traffic accident may be a factor. According to the Road Traffic Act as well as 20% to 50% in case of inclement weather, but the driver must slow speed left to the judgment of the difficulties, and to slow the vehicle and the relative velocity between the vehicle does not run longer be a big influence on the environment and safety. Thus, variable speed control for drivers on the road, specify the appropriate maximum speed limit in bad weather It keeps motorists slowed the run rate to prevent accidents or reduce the severity of accident damage is expected to be possible. The purpose of this study is the frequent traffic accidents Continuous Busan (City Freeway) around the variable speed control in the appropriate sections so that it can be done by analyzing the characteristics of traffic accidents were the severity of the accident. Highway and urban environment, the geometry of the structure because it has a lot of Curved planar point compared to wet and dry road surfaces by simulated rain wet had bom the more the speed the greater the risk of an accident was the result. Based on these results, the primary section, first urban highway tunnel, near the lamp, near Toll Plaza, near binary Outlet after considering various factors such as speed reduction is needed in the first period by conducting awareness and recognize the need for the participation of the driver and the future city installation and operation of highways in all sectors is expected to be expanded.

• Clinical and Experimental Reproductive Medicine
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• v.28 no.3
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• pp.225-233
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• 2001

Objective : To evaluate the efficacy of low-dose aspirin on IVF outcome and endometrium in patients undergoing IVF-ET. Materials and Methods : From February, 2001 to Jun, 2001, 60 infertile patients were randomly divided into study group (28 cycles) and control group (32 cycles). The study group received a daily oral dose of 25 mg of aspirin for at least 2 weeks from first visiting day. Controlled ovarian hyperstimulation was initiated in all patients with the GnRH agonist starting in the midluteal phase of the previous cycle. Results: There were no significant differences in age of the patients, basal serum E2, LH, FSH level and endometrial thickness among two groups. There were no statistically significant differences between the study group and the control group respectively in dosage ($26.5{\pm}4.8$ vs $26.2{\pm}5.3$ amples) and duration ($10.4{\pm}4.2$ vs $9.8{\pm}5.3$ days) of gonadotropin administration, serum E2 level on the hCG administration day ($1823{\pm}342$ vs $1854{\pm}543$), LH ($14.5{\pm}2.7$ vs $14.8{\pm}3.1$), FSH ($16.7{\pm}3.4$ vs $18.3{\pm}4.7$), the number of follicles > 15 mm ($13.2{\pm}6.3$ vs $12.8{\pm}5.9$), the number of oocytes retrieved ($9.2{\pm}2.4$ vs $8.4{\pm}1.7$), the number of embryos transferred ($4.7{\pm}2.0$ vs $4.7{\pm}2.0$), fertilization rate (68.4% vs 64.5%), implantation rate (21.3% vs 17.6%), and clinical pregnancy rate (28.4% vs 26.2%). The endometrial thickness and the percentage of endometrial trilaminar pattern on hCG day were significantly higher in study group than control group ($12.9{\pm}3.7mm$ vs $10.4{\pm}2.8mm$, 78.3% vs 64.5%). Conclusion: Many reports suggest that low-dose aspirin improve ovarian response, implantation rate, fertilization rate, implantation rate, and pregnancy rate by increasing the blood flow, but we couldn't prove the significant effect of low-dose aspirin on the IVF outcome except on endometrium. This may be affected by dose of aspirin, duration, and number of patients studied. This trial is small, so our results highlight the need for a large randomized controlled trial to identify the effect of low-dose as pirin on IVF-ET outcome.