• Restorative Dentistry and Endodontics
• /
• v.26 no.4
• /
• pp.341-349
• /
• 2001

Dental caries is the most common oral disease. There are many factors contributing to its development, but complete understanding and prevention are not fully known. However, it is possible to remineralize the early enamel curious lesion by fluoride containing remineralization solution. Recently the pH-cycling model has been used to examine the effect of fluoride solution on remineralization of artificial caries in vitro as it can closely simulate the conditions encountered in vivo within a carefully controlled environment. The aim of this study was to evaluate the remineralizing effects of supersaturated buffer solutions under pH-cycling model. The specimen with 3mm-diameter was made using mature bovine incisors which has no caries and has sound enamel surface. Early curious lesions were produced by suspending each specimens into demineralization solution at pH 5.0 for 33 hours and the specimen whose surface hardness value ranged from 25 to 45 VHN were used. The pH cycling treatment regimen consisted of 5 min soaks of three treatment solutions four times per days for 15 days and the continuous cycling of demineralization and remineralization were carried out for 15 days. Following the pH-cycling treatment regimen, the specimens' surface microhardness were measured by the Vickers hardness test (VHN) and analyzed by ANOVA and Duncan's multiple-range test. 1. The surface microhardness value of supersaturated solution, Senstime, and Gagline groups were increased after pH cycling, and that of supersaturated solution was significantly Increased compared to saline group(P<0.05). 2. The surface remineralization effect of fluoride containing solutions was accelerated by saliva under pH-cycling mode 3. The pH cycling model was considered appropriate to mimic the intra-oral pH changes when evaluating demineralization and remineralization in vitro. Under the results of above study, salivary remineralization effect can be improved by fluoride containing remineralization solution. The pH-cycling model was considered appropriate to mimic the intra-oral pH changes when evaluating demineralization and remineralization in vitro.

• Fashion & Textile Research Journal
• /
• v.22 no.5
• /
• pp.595-606
• /
• 2020

This study develops an optimal two-dimensional (2D) pattern from three-dimensional human scan data by considering the cycling posture and dermatome of high school male cyclists. By analyzing the body surface change in the cycling posture and considering the dermatome of the lower limbs, the optimal cutting line setting and the development of cycling tights for individual cyclists were presented to provide data that could be used in the clothing industry. We designed three cycling tights to solve the size unsuitability. 3D design 1 is a non-extension design based on the analysis of the 3D human body scan data, in which parts were connected diagonally from the front of the knee to the back of the knee. 3D design 2 removed both the front and back to reduce air resistance during cycling. 3D design 3 did not have a cutting line on the front panel because of the air resistance during cycling in the front area. We analyzed the garment pressure for 8 points of lower body and performed a subjective evaluation of the 3D designed tights and the current cycling tights. The 3D design 1 in this study was well received in the omphalion, thigh, and hip area, while 3D design 3 was well received in the omphalion, thigh, hip, and bottom bands. Therefore, the LoNE of 3D design 1 was applied to the front, and the hip cutting line of 3D design 3 was applied to the back.

• Journal of Biomedical Engineering Research
• /
• v.17 no.3
• /
• pp.327-336
• /
• 1996

This study was performed to investigate the effec% of immersion in water and thermal cycling on the mechanical peoperties of light cured restorative composite resins. Five commerically available light-cured composite resins(Photo Clearfil A : CA, Lite-Fil A . LF, Clearril Photo Posterior CP, Prisms AP.H.. PA, 2100 : ZH) were unto The specimens of 12 m in diameter and 0.7 m in thickness were made, and an immersion in $37^{\circ}C$ water for 7 days and a thermal cycling of 1000 cycles at 15 second dwell time each in $5^{\circ}C$ and $55^{\circ}C$ baths were performed. Biaxial flexure test was conducted using the ball-on-three-ball method at the crosshead speed of 0.5mm/min. In order to investigate the deterioration of composite resins during the thermal cycling test, Weibull analysis for the biaxial flexure strengths was done. Fracture surfaces and the surfaces before and after the thermal cycling test were examined by SEM. The highest Weibull modulus value of 10.09 after thermal cycling tests which means the lowest strength variation, was observed in the CP group, and the lowest value of 4.47 was obsered in the LF Group. Biaxial flexure strengths and Knoop hardness numbers significantly decreased due to the thermal cycling ($\textit{p}$< 0.01), however, they recovered when specimens were drie4 The highest biaxial flexure strength of 125.65MPa was observed in the ZH group after the thermal cycling test, and the lowest value of 64.86MPa was observed in the CA group. Biaxial flexure strengths of ZH and CP groups were higher than those of PA, CF, and CA groups after thermal cycling test($\textit{p}$< 0.05). Knoop hardness numbers of CP group after the thermal cycling test was the highest(95.47 $\pm$ 7.35kg/$mm^2$) among the samples, while that of CA group was the lowest(30.73 $\pm$ 2.58kg/$mm^2$). Knoop hardness numbers showed the significant differences between the CP group and others after the thermal cycling test(($\textit{p}$< 0.05). Fracture surfaces showed that the composite resin failure developed along the matrix resin and the filler/resin interface region, and the cracks propagated in the conical shape from the maximum tensile stress zone.

• Journal of Environmental Health Sciences
• /
• v.12 no.1
• /
• pp.39-45
• /
• 1986

This study was designed to observe the effect of temperature cycling on the production of aflatoxin by Aspergillus parasiticus R-716 in rice, barley, peanut and soybean. In those media, temperature cycling resulted in more total aflatoxin production by the strain of R-716 than constant incubation at $28{\circ}$C and natural condition did. Especially, high level of total aflatoxin ($1826{\mu}g$/30g) in rice medium at temperature cycling was produced. The intensity of yellow color of chloroform extracts correlated with the concentration of aflatoxin, and the ratio of aflatoxin $B_1$ to aflatoxin $B_2, G_1, G_2$ is lower at temperature cycling condition than at $28{\circ}$C.

• Korean Journal of Organic Agriculture
• /
• v.19 no.4
• /
• pp.463-474
• /
• 2011

The objectives of this study were to establish of resource cycling agricultural system focused on farmer's organization. Case is selected as the farming corporation for the regional agriculture considering the amount of sowing by-products and livestock by-products generated. As a result, generation of fertilizer ingredient depend on feces and urine of Korean native cattle is estimated nitrogen 7.7 ton, phosphoric acid 2.9 ton, and potassium 4.9 ton. On the other hand, generation of fertilizer ingredient demand in cultivated acreage is estimated nitrogen 42.4 ton, phosphoric acid 14.3 ton, and potassium 17.0 ton. Therefore, optimum livestock numbers is estimated 1,867 cattle and it means 1,468 cattle can be raise additionally. In order to complete the resource cycling agricultural system, it should be establish nutrient management system at all of organization level and achieve improvements in regional resource supply. Both economic value of organic fertilizer and the resource cycling system linked market system is considered to develop resource cycling level.

• Journal of information and communication convergence engineering
• /
• v.17 no.2
• /
• pp.142-148
• /
• 2019

Relatively few countries provide separate bicycle lanes for cyclists. Hence, tools for suggesting cycling routes are essential for a safe and pleasant cycling experience. This study aims to develop a mobile application to build cycling routes based on user preferences, specifically location, search radius, ride distance, and number of optimal routes. Our application calls the Strava API to retrieve Strava cycling segments crowdsourced from the cycling community. Then, it creates a graph consisting of the start and end points of these segments. Beginning from a user-specified location, the depth-first search algorithm (DFS) is applied to find routes that conform to the user's preferences. Next, a set of optimal routes is obtained by computing a trade-off ratio for every discovered route. This ratio is calculated from the lengths of all segments and the lengths of all connecting paths. The connected routes can be displayed on a map on an Android device or exported as a GPX file to a bike computer. Future work must be performed to improve the design of the user interface and user experience.

• Transactions of the Korean hydrogen and new energy society
• /
• v.12 no.3
• /
• pp.177-189
• /
• 2001

T hydrogen absorption-desorption behavior induced by thermal or hydrogen pressure cycling in a closed system was observed in hydrogen storage alloys, $(La-R-Mm)Ni_{4.5}Fe_{0.5}$, $MmNi_4Fe_{0.85}Cu_{0.15}$ and $(Ce-F-Mm)Ni_{4.7}Al_{0.2}Fe_{0.1}$. Thereby (La-R-Mm), Mm and (Ce-F-Mm) refer to La-rich mischmetal, mischmetal and Ce-free mischmetal respectively. As the results, it is found that the alloy stabilities during thermal cycling varies with alloy composition change. The highest stability occurs in $MmNi_4Fe_{0.85}Cu_{0.15}$ and the lowest stability in $(La-R-Mm)Ni_{4.5}Fe_{0.5}$. Comparing hydrogen pressure cycling with thermal cycling, pressure cycling causes severer degradation of the alloy $(Ce-F-Mm)Ni_{4.7}Al_{0.2}Fe_{0.1}$ than thermal cycling. When the 1500 times-cycled alloy is annealed at $400^{\circ}C$ for 3hrs under 1 atm of hydrogen pressure the hydrogen storage capacity is recovered only partially but not completely to the initial capacity. The amount of capacity loss after annealing is larger in the hydrogen pressure cycled samples than in the thermal cycled, suggesting an incoming of impure gas during hydrogen pressure cycling.

• Journal of the Korean Society of Costume
• /
• v.65 no.6
• /
• pp.36-47
• /
• 2015

The purpose of this study is to provide essential information conducive to designing efficient cycling apparel for everyday wear. To this end, this study identified key situations that cyclists face while riding their bicycles as well as clothing functions that are necessary for each situation. Furthermore, this study also analyzed the current trends in cycling apparels and hybrid designs. In order to analyze the current trends of clothing functionality in domestic and foreign cycling apparel brands, the researchers of this study first reviewed existing literature on the functionality of cycling clothing. Then a focus group, which comprised of two experts in cycling fashion brands and fourteen consumers, was formed and in-depth interviews were conducted to identify the major conditions related to bicycle riding. Based on the results of the interview, the study, then, classified 700 images of cycling clothing from exhibitions and 1,541 images of cycling clothing that were launched by domestic and foreign fashion brands. The results of this study were as follows. First, there were three major conditions in bicycle riding: night riding, weather changes and riding convenience. Second, functionalities required for each riding condition were as follows: visibility for night riding, comfort, waterproofness and heat preservation properties for weather changes, and elasticity, protective properties and storage capacity for riding convenience. Finally, hybrid designs for each riding condition were different from general designs.

• Journal of Korean Physical Therapy Science
• /
• v.17 no.1_2
• /
• pp.1-9
• /
• 2010

Background: The objective of this study was to determine whether sensorimotor training using an unstable surface affects dynamic balance and gait function in patients with hemiparesis, and to compare the effect of sensorimotor training with that of cycling exercise. Methods: Two subjects with post-stroke hemiparesis volunteered to participate in this study. Single-subject A-B design with alternating treatment was used for this study. Baseline(A) and intervention(B) phases were performed for 7 and 8 sessions, respectively. Sensorimotor training and cycling exercise were performed for 20 minutes in randomized order. Assessment tools were made by using a step test, timed up and go(TUG) test, and 6-minute walk test(6MWT). Results: Each of the participants improved in all three tests after the two interventions. Participants 1 and 2 showed the improvement for their assessment score after sensorimotor training in the step test by 42.1%(p<.05) and 58%, in the TUG, 31% and 19.5%, and in the 6MWT test, 32.3% and 10.6%(p<.05), respectively. After cycling exercise, participants 1 and 2 also improved in the step test by 32.5% and 53.1%, in the TUG, 27.4% and 18%, and in the 6MWT test, 28.8% and 3%. In statistical analysis between the two interventions, sensorimotor training showed a significant increased values in the step test for participant 1 and the 6MWT for participant 2 as compared with those of cycling exercise. Conclusion: Sensorimotor training and cycling exercise are helpful for improving dynamic balance and gait capacity. Furthermore, sensorimotor training may be more helpful than cycling exercise.

• 한국ITS학회:학술대회논문집
• /
• v.2007 no.10
• /
• pp.225-229
• /
• 2007

Recently, wireless sensor networks are deployed in various applications range from simple environment monitoring systems to complex systems, which generate large amount of information, like motion monitoring, military, and telematics systems. Although wireless sensor network nodes are operated with low-power 8bit processor to execute simple tasks like environment monitoring, the nodes in these complex systems have to execute more difficult tasks. Generally, MAC protocols for wireless sensor networks attempt to reduce the energy consumption using duty cycling mechanism which means the nodes periodically sleep and wake. However, in the duty cycling mechanism. a node should wait until the target node wakes and the sleep latency increases as the number of hops increases. This sleep latency can be serious problem in complex and sensitive systems which require high speed data transfer like military, wing of airplane, and telematics. In this paper, we propose a solution for reducing transmission latency through distributed duty cycling (DDC) in wireless sensor networks. The proposed algorithm is evaluated with real-deployment experiments using CC2420DBK and the experiment results show that the DDC algorithm reduces the transmission latency significantly and reduces also the energy consumption.