• The Journal of Korean Academy of Prosthodontics
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• v.39 no.5
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• pp.556-575
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• 2001

For the improvement of denture fitness of changed residual ridge, denture liner can be used. Denture liner should be very stable physically in various environments of the mouth as well as be bonded strongly with denture resin. In this study. the specimens bonded with four kinds of soft denture liner and three kinds of hard denture liner were used to test the physical properties of the liners. All experimental groups were stored in $37{\pm}1^{\circ}C$ distilled water for 24hours, followed by thermocycling between $15^{\circ}C$ and $45^{\circ}C$ with 15 second dwell time. 1000, 2000, 3000 cycles of thermocycling were excuted and physical properties were measured by Instron Universal Testing Machine. The obtained results were as follows : 1. In tensile bond test of sea liners, it was shown that both of $Molloplast-B^{(R)}$ specimens before and after thermocycling had the highest tensile strength, and in case of hard liners, Dura-Liner $II^{(R)}$ specimen had the highest tensile strength before and after thermocycling. Depending on thermocycling, $Soft-Relining^{(R)}$, $Denture-Relining^{(R)}$, $Molloplast-B^{(R)}$, $Coe-Soft^{(R)}$ and $Kooliner^{(R)}$ specimen showed significant difference(p<0.05). 2. In strain test of soft liners, it was shown that $Molloplast-B^{(R)}$ specimen before thermocycling and the $Coe-Soft^{(R)}$ after thermocycling showed highest results, and in case of hard liners, the Dura-Liner $II^{(R)}$ specimen before and after thermocycling had the highest result. Depending on thormocycling, $Denture-Relining^{(R)}$, $Molloplast-B^{(R)}$ and Dura-Liner $II^{(R)}$ specimen showed significant difference(p<0.05). 3. In maximum distance test of soft liners. the $Molloplast-B^{(R)}$ specimen before thermocycling and the $Coe-Soft^{(R)}$ after thermocycling showed highest results. and in case of hard liners, the Dura-Liner $II^{(R)}$ specimen before and after thermocycling showed highest result. Depending on thermocycling, $Denture-Relining^{(R)}$, $Molloplast-B^{(R)}$ specimens showed significant difference(p<0.05). 4. In elasticity test of soft liners, the $Molloplast-B^{(R)}$ specimen before and after thermocycling showed highest result. and in case of hard liners, the Dura-Liner $II^{(R)}$ specimen before thermocycling and the $Tokuso-Rebase^{(R)}$ after thermocycling showed highest results. Depending on thermocycling, $Soft-Relining^{(R)}$ $Molloplast-B^{(R)}$ specimens showed significant difference (p<0.05).

• Archives of design research
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• v.17 no.3
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• pp.293-302
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• 2004

The austere standard for industrial design and the machine aesthetic reinforced modernism and lasted more than a half century. Pop art and Pop design movements, which were opposite of the elite culture, began to appear as anti-modernism in the late 1950s. With the development of technology, the movements helped to establish humanism design style that reflected the life style of young generation and their culture. From the 1960s. it was a try in order to fulfill psychologically users' needs beyond tasks for physical considerations. The efforts appeared as a various appearance in different contexts. It could settle down on industrial design, based on humanism both from the physical and psychological points ol views, through anti-modernism in the 1960s, commercialism, consumerism and hi-tech in the 1970s, and postmodernism in the 1980s. The design, as a specific style in industrial design, delivers both physical and psychological satisfaction to consumers by using a mixture of human emotions with high technology. Accordingly, this study is to find out and to define the design style that was applied by human emotion and sensibility in design history from the 1960s to the 1980s. It will be underpinnings for the next research about how the design style has developed nowadays.

• Journal of Korean Society of Forest Science
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• v.108 no.1
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• pp.67-76
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• 2019

With an increasing demand of timber production, the use of heavy machinery in forest management has significantly increased, causing the changes of soil physical properties and the decline of long-term site productivity. This study was conducted to evaluate the effects of logging slash (non-slash, slash $7.3kg/m^2$, and slash $11.5kg/m^2$) and machine passes(harvester 1 pass and forwarder 1 to 10 passes) on soil physical properties at 10 cm, 20 cm and 30 cm soil depths in harvester and forwarder operations and also to estimate the degree of soil surface disturbance. The results indicated that soil bulk density in the non-slash treatment site increased 10 %~29 % (25~139 % in soil penetration resistance) at all soil depths, compared with the slash treatment site(slash $11.5kg/m^2$). Therefore, the creation of a slash mat could be an effective way to minimize the changes of soil physical properties. In addition, 92 % of total soil compaction in slash treatment site was created within harvester 1 pass and forwarder 5 passes. In non-slash treatment site, 84 % of total soil compaction was created within first harvester and forwarder passes. The results showed that slash treatment was effective to reduce soil compaction caused by machine passes and also it is necessary to create designed forwarding trails for minimizing soil compaction area at timber harvesting sites.

• Food Engineering Progress
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• v.14 no.3
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• pp.193-201
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• 2010

The aim of this study was to analyse the quality of Yukwa puffed by using a vacuum puffing machine and compare to deep-fried Yukwa. The effect of vacuum puffing condition including heating temperature(100-${160^{\circ}C}$), preheating time(0-8 min) and vacuum puffing time(5-20 min) on physical and microstructure characteristics of the Yukwa was investigated. Vacuum puffed Yukwa at ${100^{\circ}C}$ heating temperature, 6 min preheating time and 10 min puffing time had highest value in volumetric expansion ratio(10.04) and lowest value in bulk density(0.15 g/$cm^{3}$). The breaking strength showed the lowest value of 140 g/$cm^{3}$ in vacuum puffing Yukwa at ${100^{\circ}C}$ heating temperature, 6 min preheating time and 15 min puffing time. The Yukwa puffed with the vacuum puffing machine at ${100^{\circ}C}$ heating temperature, 6 min preheating time and 15 min puffing time had the higher value of bulk density and the lower value of volumetric expansion ratio than those of deep-fried Yukwa. Increasing preheating time and vacuum puffing time caused an increase in white and an decrease in yellowness. The vacuum-puffed Yukwa exhibited smaller and uniform cell structure, while deep-fried Yukwa exhibited apparently in larger pores inside and smaller pores near the surface layer. The optimum condition of vacuum puffing machine for the production of vacuum-puffing Yukwa was ${120^{\circ}C}$ heating temperature, 4 min preheating time and 5 min puffing time.

• Journal of Biosystems Engineering
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• v.12 no.2
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• pp.28-37
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• 1987

Operation of rice whiteners has been depending on operator's experience only and very limitted data are available for operational criteria of rice whiteners in Korea. With developments of new rice varieties and with a tendency of automation of machine operations for precision control, operational criteria depending on physical characteristics of rice grains arc required for an improvement of milled rice recovery and the performance of rice whitening systems. An experimental study was conducted to identify operational criteria of a rice whitening system consisted with an abrasive-aerated whitener developed newly and a frictional-aerated whitener being used commercially. Further, comparisons were made between the performance of the rice whitening system adopted for this study and a commercial system used in small scale milling plants. Results of this study are summarized as follows: 1. Total number of passes necessary for the final white rice in the combined whitening system depended exclusively on the counter pressure level of the frictional whitener successive to the abrasive whitener. 2. The counter pressure required for whitening Japonica type rice variety (Akibare) was higher by about 1.6 times than that for Japonica type (Pung-san), when other conditions were kept at the same. 3. Radial pressure in the whitening chamber of the frictional whitener should be maintained between 1.5 to $2.1kg/cm^2$ for the completion of whitening within 5 to 3 passes regardless of rice varieties. Hence, it was found that the radial pressure in the whitening chamber could be used as an operational criteria to control the counter pressure level. 4. The following regression equation was found between radial pressure($R_p$) in whitening chamber and electric power consumption of the whitening system: $$EPC=-0.545\;R^2_p+1.277\;R_p+0.874[KWH/100kg]$$ 5. The following multiple regression equation was found among radial pressure ($R_p$), counter pressure ($C_p$), and bioyield point ($B_i$), length (L) and width (W) of brown rice. $$R_p/(B_i/W^2)=0.547\{C_p/(B_i/W^2)\}^{0.365}(L/W)^{0.120}(R^2=0.9897)$$ 6. The milled rice recovery and machine efficiency (kg/KWH) from the combined whitening system were higher by about 2.0% point and by 15 to 27% point than those from the conventional system, respectively.

• Korean Journal of Soil Science and Fertilizer
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• v.27 no.2
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• pp.117-124
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• 1994

A study was conducted to dectermine the days with optimum soil moisture after drainage or rain for machine workability and seeding establishment on dry seeding in paddy soils(Jeon buk Series, Haplaquepts). The results are summarized as follows. 1. The possible days of tractor-rotary plough were 5days or more for non-mole hole plot(control). The possible days were 2~4days and the optimum days were 5~6days for mole hale plat. 2. The ratio of soil clod(<1cm) was 1 % and 15% for control and mole hole plats, respectively. The optimum soil moisture range for seeding establishment was 31~32% in this soils. 3. The possible days of combine harvesting work were 9days and 5days after drainage for control and mole hole plots, respectively. 4. Soil physical properties were improved but soil organic matter calcium and magnesium in the soil were decreased in the mole hole plats. 5. Yield was 415kg/10a at seeding after 6day drainage in control and 440kg/10a at seeding after 4day drainage in the mole plots.

• Korean Security Journal
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• no.50
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• pp.341-366
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• 2017

Today, crime has become a serious threat to social safety so citizen's desire for safety has increased. So the private security has emerged as a new industry for safety and security and became a crucial component. Private security is responsible not only covers the limitations of the police work, but also fills citizen's desire of security. However, quantitative research on private security has rarely been done and the results of the private security study are not effectively utilized due to biased research trends in Korea. Therefore, the purpose of this study is to evaluate the effects of community incivility on fear of crime and the moderation effect of private security. To accomplish this purpose, this research uses 6,919 samples from the National Crime Victimization Survey(2014) and conducts hierarchical regression through STATA 13.0 program. As a results, private security guard showed the main effect on the generalized fear of crime, but had not a significant influence on the interaction effect with the community incivility. On the other hand, the moderation effect of electronic security was statistically significant in relation to the community incivility and specific fear of crime. In other words, in a place with high physical disorder, the fear of crime is relatively low in the case of the electronic machine, compared with the case where there is no electronic machine. The implications and limitations based on these results are discussed in the conclusion.

• Cartoon and Animation Studies
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• s.30
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• pp.27-57
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• 2013

Animation which appeared with films in the late 19th century was a medium which came on obtaining nourishment from art historical style of modernism. However, the relation establishment between animation and modernism has been focused mainly on animation shapes, namely painted images. This sprang from explaining the relationship between animation and paintings, and for this reason, discussions of movements in animation were understood in tradition of chromophotograph of Muybridge and Jules Marey, or some characteristics owned by the live-action film. However, movements of animation were essentially different from the indexical sign of films or photogram, and objects of reproduction were different between them. Movements reproduced by animation are not ordinary movements, but expressions of or compressed movements and considerably systematic movements. As a result, these movements are far from reproduction of live-action film photogram. Rather, the logic of movements reproduced by animation comes near to controlling their motion scopes, time, distance etc. after dividing each part of the body. This is concluded in a standpoint of modern mechanism which is represented by Descartes and La Mettrie who tried to understand human body as a exchangeable machine. Design of modern mechanism ranging from modern society to industrial society and the age of modernism came to lead to analysis of physical motions of modern industrial society called composition of efficient movements understanding them as the law of nature rather than movements as nature. In the late 19th century, Taylor, F. W. and Gilbreth, Frank Bunker's studies of workers' working hours and 'motion study' were a way of constituting the frame of machine-human, which indicates that tradition of modern mechanism affected the entire modernism passing through industrial society. Further, we can see that motion studies conducted by them have almost similar characteristics to action analysis to study animation later in the name of 'timing'.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.12
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• pp.581-588
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• 2017

This study was conducted to determine which factors would predict metabolic syndrome (MetS) perception and exercise by applying a machine learning classifier, or Extreme Gradient Boosting algorithm (XGBoost) from July 2014 to December 2015. Data were obtained from the Korean Community Health Survey (KCHS), representing different community-dwelling Korean adults 19 years and older, from 2009 to 2013. The dataset includes 370,430 adults. Outcomes were categorized as follows based on the perception of MetS and physical activity (PA): Stage 1 (no perception, no PA), Stage 2 (perception, no PA), and Stage 3 (perception, PA). Features common to all questionnaires for the last 5 years were selected for modeling. Overall, there were 161 features, categorical except for age and the visual analogue scale (EQ-VAS). We used the Extreme Boosting algorithm in R programming for a model to predict factors and achieved prediction accuracy in 0.735 submissions. The top 10 predictive factors in Stage 3 were: age, education level, attempt to control weight, EQ mobility, nutrition label checks, private health insurance, EQ-5D usual activities, anti-smoking advertising, EQ-VAS, education in health centers for diabetes, and dental care. In conclusion, the results showed that XGBoost can be used to identify factors influencing disease prevention and management using healthcare bigdata.

• Journal of the Korea institute for structural maintenance and inspection
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• v.20 no.3
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• pp.10-17
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• 2016

This paper presents a laboratory validation of a new approach for Finite Element Model Updating(FEMU) on short-span bridges by combining ambient vibration measurements with static load input-deflection output measurements. The conventional FEMU approach based on modal parameters requires the assumption on the system mass matrix for the eigen-value analysis. The proposed approach doesn't require the assumption and even provides a way to update the mass matrix. The proposed approach consists of two steps: 1) updating the stiffness matrix using the static input-deflection output measurements, and 2) updating the mass matrix using a few lower natural frequencies. For a validation of the proposed approach, Young's modulus of the laboratory model was updated by the proposed approach and compared with the value obtained from strain-stress tests in a Universal Testing Machine. Result of the conventional FEMU was also compared with the result of the proposed approach. It was found that proposed approach successfully estimated the Young's modulus and the mass density reasonably while the conventional FEMU showed a large error when used with higher-modes. In addition, the FE modeling error was discussed.