• International conference on construction engineering and project management
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• 2017.10a
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• pp.201-209
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• 2017

Facade structure system plays an important role in modern architecture and design. Many contractors start using Building Information Modeling (BIM) to help design and lay-out façade walls in recent years. However, there are still some users refuse to accept BIM on façade construction. Therefore, we employed Technology Acceptance Model (TAM) to assess the users acceptable of BIM work flow, with using a practical case of facade construction in Chongqing Wanda City. The factors that will affect the builder's decision of whether using BIM or not when construct façade, and the relationship among them will be found via this model. Through the analysis using TAM, this research found that the direct factors influencing the completely acceptance of BIM in façade construction is the BIM quality and Result Demonstrating, and the parameter impacting the intuition engendering is the Exterior Condition. Therefore, this paper proposes a more systemic model of BIM acceptance in curtain wall to analyze the user's acceptance. The solution can also offer a reference for future research and construct on façade structure. The acceptance model has the significance that it can help to analyze the reason why users refuse to use BIM in façade construction, thus to help users accept BIM.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.13 no.2
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• pp.15-26
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• 2018

This study examines the effects of failure experience, re-startup's motivation, government support business and education for re-startup on the performance of re-startup firms after failure. In addition, we analyzed how the above factors affect the performance of re-startup firms by the condition of debt and credit problems. As a result of the analysis, the failure experience had no significant effect on the re-startup performance regardless of the credit problem, while re-startup's motivation, government support business and education for re-startup had a significant effect on re-startup firms' performance. In the re-startup group with the credit problem, the re-startup's motivation and the failure experience had a significant influence on the re-startup firms' performance. On the other hand, in the group that did not solve the credit problem, the re-startup's motivation and the failure experience had no significant effect on the re-startup performance, but the government support business and education for re-startup had a significant effect on re-startup performance. The results of this study are as follows: First, it shows that the characteristics of re-startups and the determinants of re-startups are different according to credit problems. Second, this study shows that it takes 56 months on average from the close of business to the re-start, and it may take more than 7 years due to the credit problems and bankruptcy. This suggests the necessity to consider re-startup in the concept of obsolete in consideration of time, when studying the direct/indirect influence of failure experience and re-startup, and establishing policy.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.4
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• pp.361-370
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• 1982

The effects of climatic factors on organisms lire variable and complex, and it, however, can be interpreted in terms of those on the distribution and those on the population densities. The distribution of an organism may largely be determined by the temperatures, except some temporal organisms which are depended on the air mass movements. Population density of an organism is determined by various climatic factors, such as previous winter temperature, temperature of growing season and rainfall. The start of growing season of the rice plants has been shifted to earlier since last decade in Korea. This may mean that the overall climatic condition during the growing season might be considerably different from those in past years, and such a difference in climatic conditions might have close relation with the recent status of the diseases and insect pests through direct effects on the physiology and population dynamics of the organisms, as well as through on the biotic associations of the pest organisms. The white back planthopper and brown planthopper have become the key insect pests in Korea in recent years. They are migratory and have high reproductive pontentials and more generations than average residential insects. The synchronization of the migrants and physiological condition of the rice plants seems to be the important factors in relation to the recent outbreaks of these insects; the high reproductive rate can be obtained with the growth stage of rice being 30-50 days after transplanting. The modication of the microclimate associated with high plant density and some other introduced new cultural techniques also have some relation with the outbreak. The key diseases of the rice are the blast disease, sheath blight and the bacterial leaf blight. For the rice blast, the seedling blast and leaf blast during the early growing season and the neck blast, have become more serious, the former may be related to hotbed nursery and the later may be related to the high humidity in early August, and synchronization of the heading time which has been shifted to early part from middle or late part of August. In general, for the rice diseases, the development of the new races have been the most serious which are largely resulted from the introduction of the new varieties, but it also seems to be related with the prolonged periods of the favorable condition associated with the shifted growing seasons. In general, the diseases and insect pest problems have become much more variable and complex, and control measures should be based on the thorough knowledge of the ecology of the pest organisms, that is, effects of various environmental factors on the disease cycle; spore release, spore deposition, infection, colonization and sporulation of the disease organisms, and those on the development, reproductive potentials, dispersal, age specific responses of the insects. The well organized real-time pest management systems, such as alfalfa weevil management system developed at the Purdue University in U.S., is the prime importance for the implementation of the pest management principles.

• Journal of the korean academy of Pediatric Dentistry
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• v.34 no.1
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• pp.106-121
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• 2007

The purpose of this study was to examine the effects of suggested etching method on the performance of pits and fissures sealant. In the first part, seventy extracted sound human permanent third molars and premolars were used. The teeth were randomly divided and performed in three different groups as follows : conventional etching, enameloplasty, and testing group. Non-pumicing, dye-guidance vigorous brushing-start etching technique was applied on the occlusal of testing group. Then the pit and fissure sealant was applied on all of the specimens. After the thermocycling and immersing in 1% methylene blue, the resin embedded sections were made. The microleakage data on the section were then recorded under the stereoscope and statistic analysis was done. Additional experiments were also performed : direct fissure surface etched pattern experiment, replica study, and micro-shear bond strength testing observation. The second part included two groups. A paired study was designed to evaluate the influence the environment has on the performance of the sealant. After etching, half of each occlusal surface received one of the two following treatments in succession: sealing in laboratory and intraoral condition (group 1), sealing in intraoral condition with and without a single-bonding agent (group 2). The results of present study can be summarized as follows: - The microleakage of testing group was significant different with conventional method (P<.05) and was not different with the enameloplasty group (P>.05). - The quality and quantity of etched enamel were improved. - Microshear bond strength of testing group was higher than control group (p<.05). - The environmental condition was influenced on the performance of the sealant. The testing etching method modified the capacity of the etching agent to penetrate into the pits and fissures, and simultaneous enhance their efficiency in vitro condition.

• International Journal of Automotive Technology
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• v.8 no.4
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• pp.437-444
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• 2007

This paper experimentally investigates the effects of oxygen-enriched air (OEA) on the running behaviors of an LPG SI engine during both start/warm-up (SW) and hot idling (HI) stages. The experiments were performed on an air-cooled, single-cylinder, 4-stroke, LPG SI engine with an electronic fuel injection system and an electrically-heated oxygen sensor. OEA containing 23% and 25% oxygen (by volume) was supplied for the experiments. The throttle position was fixed at that of idle condition. A fueling strategy was used as following: the fuel injection pulse width (FIPW) in the first cycle of injection was set 5.05 ms, and 2.6 ms in the subsequent cycles till the achieving of closed-loop control. In closed-loop mode, the FIPW was adjusted by the ECU in terms of the oxygen sensor feedback. Instantaneous engine speed, cylinder pressure, engine-out time-resolved HC, CO and NOx emissions and excess air coefficient (EAC) were measured and compared to the intake air baseline (ambient air, 21% oxygen). The results show that during SW stage, with the increase in the oxygen concentration in the intake air, the EAC of the mixture is much closer to the stoichiometric one and more oxygen is made available for oxidation, which results in evidently-improved combustion. The ignition in the first firing cycle starts earlier and peak pressure and maximum heat release rate both notably increase. The maximum engine speed is elevated and HC and CO emissions are reduced considerably. The percent reductions in HC emissions are about 48% and 68% in CO emissions about 52% and 78%; with 23% and 25% OEA, respectively, compared to ambient air. During HI stage, with OEA, the fuel amount per cycle increases due to closed-loop control, the engine speed rises, and speed stability is improved. The HC emissions notably decrease: about 60% and 80% with 23% and 25% OEA, respectively, compared to ambient air. The CO emissions remain at the same low level as with ambient air. During both SW and HI stages, intake air oxygen enrichment causes the delay of spark timing and the increased NOx emissions.

• Korean Journal of Veterinary Research
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• v.41 no.4
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• pp.603-609
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• 2001

A transport stress is one of the main causes of economic losses and physiological dysfunction. The present study has been performed to suggest a method to decrease the adverse effects above mentioned from transport. The groups were prepared as follows; (1) Control group : 4 cattle transported for 5 hrs (274 km) without any treatment, (2) Treatment group : 4 cattle treated with electrolyte-mineral solution (I.V.) at 1 hr before the enrollment of transport under same experimental condition with Control group. The blood specimens were collected at 1 hr before transport, 2.3 hrs (135 km) and 5 hrs (274 km) after the enrollment of transport, and 1, 6 and 18 hrs after fulfillment of transport. The collected blood specimens were analyzed for cortisol and epinephrine. Core temperature and heart rate were measured with active biotelemetry in every 30 minutes from 0.5 hr before the start of transport to 18 hrs after the end of transport. In results, the level of cortisol considerably increased to the peak either in Control group ($5.3{\pm}1.3{\mu}g/d{\ell}$) and in Treatment group ($4.0{\pm}2.6{\mu}g/d{\ell}$) at 2.3 hrs in transport. The concentration of epinephrine of Treatment group had been higher than that of Control group from the start of transport to 18 hrs after the fulfillment of transport. Particularly there was the biggest gap between Control and Treatment groups, $424.0{\pm}194.1pg/m{\ell}$ and $209.1{\pm}65.1pg/m{\ell}$ respectively, at 6 hrs after the end of transport. The heart rates were considerably increased either in Control group ($81.5{\pm}18.5$ to $126.3{\pm}7.8beats/min$) and in Treatment group ($114.3{\pm}14.4$ to $140.8{\pm}22.4beats/min$) with the enrollment of transport. These results indicate that the concentration of cortisol and the heart rate were pertinent to cognitive parameters to evaluate physiological responses against stress such as transport. In addition, the intravenous administration of electrolyte-mineral solution could be suggested as the method to decrease the adverse effects from a transport stress.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2018.05a
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• pp.347-350
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• 2018

In order for an IoT system to automatically make the house temperature pleasant for the user, the system needs to predict the optimal start-up time of air-conditioner or heater to get to the temperature that the user has set. Predicting the optimal start-up time is important because it prevents extra fee from the unnecessary operation of the air-conditioner and heater. This paper introduces an ANN(Artificial Neural Network) and an IoT system that predicts the cooling and heating time in households using air-conditioner and heater. Many variables such as house structure, house size, and external weather condition affect the cooling and heating. Out of the many variables, measurable variables such as house temperature, house humidity, outdoor temperature, outdoor humidity, wind speed, wind direction, and wind chill was used to create training data for constructing the model. After constructing the ANN model, an IoT system that uses the model was developed. The IoT system comprises of a main system powered by Raspberry Pi 3 and a mobile application powered by Android. The mobile's GPS sensor and an developed feature used to predict user's return.

• Journal of Korean Society on Water Environment
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• v.21 no.6
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• pp.687-694
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• 2005

Lab-scale experiments have been carried out to investigate the effect of F/R ratio of ASBR (Anaerobic Sequencing Batch Reactor) process on the removal of the organic matters in ammonia stripped swine wastewater. Three ASBR inoculated with sludge mixed with granular sludge of UASB (Upflow Anaerobic Sludge Blanket) and anaerobic digested sludge of municipal wastewater treatment plant were operated. Ammonia stripped swine wastewater was used as influent. Prior to conducting the experiments with varied conditions, the effect of increasing organic loading rate from 2.34 to $5.79gTCOD_{Cr}/L$-day at a fixed F/R ratio of 0.1 on the organic removal efficiency has been studied during start-up period. As the result of the experiment, under the condition of varied organic loadings, less than $4.14gTCOD_{Cr}/L$-day, the removed efficiency $TCOD_{Cr}$ of the ASBR process is 83% resulted from the mean value of effluent $TCOD_{Cr}$, 9,125 mg/L during the start-up period. Then ASBRs were operated with F/R ratio of 0.024, 0.303 and 0.91 respectively. Organic loading rate was increased from 4.56 to $15.43gTCOD_{Cr}/L$-day to investigate the effects of F/R ratio and organic loading rate on the organic removal efficiency. As the result of the experiment, less than $6.23gTCOD_{Cr}/L$/L-day, F/R ratio haven't an effect on the organic removal efficiency and the mean removal efficiency of TSS, $TCOD_{Cr}$ and $SCOD_{Cr}$ was about 80%, 86% and 78% at the all of F/R ratio. But as organic loading rate was increased from 8.54 to $12.04gTCOD_{Cr}/L$-day at the F/R ratio of 0.024, the removal efficiency of $SCOD_{Cr}$ decreased from 71% to 63%. The range of decreased removal efficiency of $SCOD_{Cr}$ at the F/R ratio of 0.024 was much more higher than at the F/R ratio of 0.303, 0.91. Thus, as organic loading rate was increased, ASBRs were operated with high F/R ratio to obtain high removal efficiency.

• KSBB Journal
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• v.20 no.6
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• pp.431-437
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• 2005

Molecular methods were employed to investigate microorganisms in a thermophilic continuous stirred tank reactor(CSTR) used for continuous $H_2$ production. The reactor was inoculated with heat-treated anaerobic sludge and fed with a glucose-based medium. Denaturing gradient gel electrophoresis showed dynamic changes of bacterial populations in the reactor during 43 days of operation. Gas composition was constant from approximately 14 days but population shift still occurred. Populations affiliated with Fervidobactrium gondwanens and Thermoanaerobacterium thermosaccharolyticum were dominant on 21 and 41 days, respectively. Keeping pH of the medium at 5.0 could suppress methanogenic activity that was detected during initial operation period. $CH_4$ and mcrA detected in the samples obtained from the reactor or inoculum suggested the heat treatment condition employed in this study is not enough to remove methanogens in the inoculum. PCR using primer sets specific to 4 main orders of methanogens suggested that major $H_2$-consuming methanogens in the CSTR belong to the order Methanobacteriales.

• The Korean Journal of Malacology
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• v.22 no.2
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• pp.175-182
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• 2006

Artificial induction of maturation by heating of the ark shell, Scapharca broughtonii (Schrenck) broodstock was investigated from 10th March to 21th May in 2004. Maturity at the fixed water temperature group of $23^{\circ}C$ was 60.5％, and it was the highest in maturity among experimental groups cultured for seven weeks. The proportions of organism surviving to start of S. broughtonii in the raised water temperature experimental groups (20 and $23^{\circ}C$) were over 90.5％, as similar to the control group (natural water temperature, 84.8％). But, the proportions of organism surviving to start of S. broughtonii in the fixed water temperature experimental groups (20, 23, and $26^{\circ}C$) were decreased with the increasing of the water temperature. In the fixed water temperature experimental groups of $26^{\circ}C$, the survival was 18.1％. Base on these results, the fixed water temperature of $20^{\circ}C$ (accumulated water temperature; $1,295^{\circ}C$) was the best condition for artificial induction of sexual maturation.