• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.36 no.3
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• pp.52-59
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• 2004

The greater Increase of the demand for environmental friendly materials especially for packaging industry leads to the larger interest in the reusable and recycable materials such as pulp mold. Although the pulp mold has great characteristics for packaging, some deficiency compared with other packaging material like EPS(Expandable Polystyrene) need to be overcome, for example, the relative higher cost. In this report, since the water drainage rate at the forming zone of a wet pulp mold process could have a great influence on the economical efficiency not only by increasing machine speed but also reducing the drying energy, the optimum ways for increasing drainage were investigated The mechanism of vacuum drainage In pulp mold forming was successfully evaluated by using RDA(Retention and Darinage Analyzer). Since the conditions of stock were greatly affected by the pulping time of low consistency pulper, the optimum pupling time was investigated with considerations of all stock preparation processes. The change of stock temperature and the addition of polyelectrolyte could improve the vacuum drainage rate. It was founded that the wire mesh types of mold former had a little influence on the retention because of the relatively mild vacuum drainage. However, the bigger size of dewatering hole showed better drainage rate and could reduce the plugging and con lamination of mold.

• Structural Engineering and Mechanics
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• v.5 no.4
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• pp.339-353
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• 1997

Fiber reinforced plastic (FRP) rods provide certain benefits over steel as concrete reinforcement, such as corrosion resistance, magnetic and electrical insulation, light weight, and high strength. FRP composites can be combined with a steel core to form hybrid reinforcing rods that take advantage of properties of both materials. The objective of this study was to characterize the bond behavior of hybrid FRP rods made with braided epoxy-impregnated aramid or poly-vinyl alcohol FRP skins. Eleven rod types were tested using two concrete strengths. Specific topics examined were bond strength, slip, and type of failure in concentric pull-out tests from concrete cubes. From analysis of identical pull-out tests on both hybrid and steel rods, information on relative bond strength and behavior were obtained. It is concluded that strength is similar but slip in hybrid rods is much higher. Hybrid rods failed either by pull-out or splitting the concrete block (with or without yielding of the steel core). Experimental data showed consistency with similar test results presented in the literature.

• Journal of Environmental Science International
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• v.16 no.1
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• pp.55-63
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• 2007

There are concerns that chemical residues could harm the consumer on the environment, although 50 to 80% of the crops would be destroyed by pests and others without agrochemicals. Environmental fate and ecotoxicity studies are usually carried out to assess the impact on the human and the environment. A comparision of the Daphnia magnia and Simocephalus mixtus toxicity was performed to study the relative sensitivities and discrimination abilities to agriculture chemicals. The species of Simocephalus mixtus was more sensitive to agriculture chemicals than Daphnia magnia. Simocephalus mixtus was approved to be a water flea in determining insecticide and pesticide toxicity by heart-beat rate in a consistency and repeatability. The order of acute toxicity to water flea Daphnia magnia for ecotoxicity test was carbaryl>benomyl>amtirole with both Daphnia magnia and Simocephalus mixtus. The heartbeat pattern after the exposure to agrochemicals was different from that of exposure to heavy metals. Agrochemical leathal concentration test with heartbeat rate measurement was found to be more appropriate than inhibition concentration test with respect to toxicological endpoint.

• Journal of the Ergonomics Society of Korea
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• v.32 no.1
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• pp.47-58
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• 2013

Objective: The aim of this study is to review the job stress measurement for applying in nuclear power plants(NPPs). Background: The standard and guideline to evaluate and manage the job stress is insufficient in NPPs. Although job stress might have a negative effect on task performance particularly it can be related with human error in NPPs. Method/Results: This paper considered the objective and subjective stress measurements. One of the questionnaire(Korean Occupational Stress Scale) and the experiment method was investigated to apply in NPPs. KOSS was analyzed about the inter item consistency and correlation with the workload, and relative importance. In the objective evaluation considered the experiment method for the physical and mental job stress and analyzed from the phased point of view. Conclusion/Application: The measurement and criteria to evaluate job stress for operators must be complemented on the job characters and environments in NPPs. This study may support to confirm and manage the job stress in NPPs. The study of more specific methodology on job stress in NPPs is required on the basis of this paper.

• 한국신재생에너지학회:학술대회논문집
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• 2007.11a
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• pp.690-693
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• 2007

The R&D budget of energy technology development has increased in the sector of Korean energy technology development continuously. In addition to that, KIER, the government invested research institute and unique energy technology R&D research institute, is trying to plan for a big-sized energy R&D program for the well focused R&D and excellent research outcomes. In the phase of R&D process, the planning is one of the most important sectors because it drives the direction of R&D. In this study, we suggest the assessment criteria to select a strategic energy technology R&D programs by the analytic hierarchy process, which is one of multi-criteria decision making method (MCDM). We structure 2 tiers of hierarchy for assessing a big-sized R&D program and also establish 6 criteria in the level 1, which are energy environment, economic spin-off, technical spin-off, marketability, KIER mission, and cost. We allocate the relative weights of criteria by checking the values of consistency ratio as making pairwise comparisons. The result of this research will provide the decision makers as they select a right well focused R&D program.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.3 no.3
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• pp.24-31
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• 2004

A successful on-line monitoring system for conventional machining operations has the potential to reduce cost, guarantee consistency of product quality, improve productivity and provide a safer environment for the operator. In fine-shape machining, typical signs of tool problems such as vibration, noise, chip flow characteristics and visual signs are almost unnoticeable without the use of special equipment. These characteristics increase the importance of automatic monitoring in fine-shape machining, however, sensing and interpretation of signals ar more complex. In addition, the shafts of the mini-tools break before the typical extensive cutting edge of the tool gets damaged. In this study, the existence of a relationship between the characteristics of the cutting force and tool usage was investigated, and tool breakage detection algorithm by LabVIEW was developed and the following results are obtained. It was possible to use a relative error compare which mainly used in established experiment and investigated tool breakage detection algorithm in time domain which can detect AE and cutting force signals more effective and accurate.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.2
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• pp.250-255
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• 2001

Effect of molding temperature on the quality changes of extruded meju was studied. Meju was molded at 8$0^{\circ}C$, 6$0^{\circ}C$ and 4$0^{\circ}C$, and then stored at $25^{\circ}C$ with 50% of relative humidity for 30 days. The texture of the cooked soybean grain showed that the firmness and cohesiveness were increased, and consistency was decreased by decrease of molding temperature. The density of the meju molded at 8$0^{\circ}C$, 6$0^{\circ}C$ and 4$0^{\circ}C$ were 1.072g/mL, 1.079g/mL and 1.203g/mL, respectively. The meju molded at 4$0^{\circ}C$ had significantly higher density than those molded at 8$0^{\circ}C$ or 6$0^{\circ}C$. Also, delay of water evaporation, acidification, and rapid growth of fungal mycellium were observed on the sample with molding temperature at 4$0^{\circ}C$ during fermentation. Activity of amylase and protease, contents of total reducing sugar and amino nitrogen of 4$0^{\circ}C$-molded meju were represented lower level than those of 6$0^{\circ}C$ or 8$0^{\circ}C$-molded sample. Therefore, it was considered that the molding temperature was an important factor for meju fermentation and molding temperature of 6$0^{\circ}C$ or over would be acceptable.

• Journal of the Korea Safety Management & Science
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• v.15 no.1
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• pp.271-281
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• 2013

In the trend toward globalization, cross-cultural teams in organizations are becoming more and more common. In particular, the influence of China and Western Europe on the global economy is getting increased. With this trend, it is important to understand cross-cultural characteristics for group decision making in managerial environments. This study aims at analyzing cross-cultural differences between China and Western Europe in light of the effect of group discussion in group decision making. An experiment simulating a decision of a car purchase was conducted. A total of 48 subjects (24 Chinese and 24 Western Europeans) assigned in decision groups were asked to judge relative importance ratios of nine factors affecting their purchase decisions using the AHP program developed for the experiment. Three dependent variables (consistency, satisfaction, and consensus) were measured. Chinese were slightly more consistent than Western Europeans in discussion-involved group decision making. In terms of decision satisfaction, Western Europeans were more satisfied with discussion-included decisions than discussion-excluded decisions. Chinese, on the contrary, did not show a significant difference. There was no significant difference between two cultures in decision consensus.

• Korean Journal of Remote Sensing
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• v.24 no.1
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• pp.65-78
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• 2008

This study compares the relative accuracy and consistency of four split-window land surface temperature (LST) algorithms (Becker and Li, Kerr et ai., Price, Ulivieri et al.) using 24 sets of Terra (Aqua)/Moderate Resolution Imaging Spectroradiometer (MODIS) data, observed ground grass temperature and air temperature over South Korea. The effective spectral emissivities of two thermal infrared bands have been retrieved by vegetation coverage method using the normalized difference vegetation index. The intercomparison results among the four LST algorithms show that the three algorithms (Becker-Li, Price, and Ulivieri et al.) show very similar performances. The LST estimated by the Becker and Li's algorithm is the highest, whereas that by the Kerr et al.'s algorithm is the lowest without regard to the geographic locations and seasons. The performance of four LST algorithms is significantly better during cold season (night) than warm season (day). And the LST derived from Terra/MODIS is closer to the observed LST than that of Aqua/MODIS. In general, the performances of Becker-Li and Ulivieri et al algorithms are systematically better than the others without regard to the day/night, seasons, and satellites. And the root mean square error and bias of Ulivieri et al. algorithm are consistently less than that of Becker-Li for the four seasons.

• Analytical Science and Technology
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• v.34 no.5
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• pp.202-211
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• 2021

Volatile organic compounds (VOCs) in hazardous air pollutants (HAPs) have been regulated by the Air Pollution Control Act (1978) and their atmospheric concentrations have been monitored in 39 monitor sites in Korea. However, measurement standards of volatile organic compounds (VOCs) in HAPs at ambient levels have not been established in Korea. Primary reference gas mixtures (measurement standards) at ambient levels are required for accurately monitoring atmospheric VOCs in HAPs and managing their emissions. In this study, primary reference gas mixtures (PRMs) at 5 nmol/mol were developed in order to establish primary national standards of VOCs in HAPs at ambient levels. Primary reference gas mixtures (PRMs) were prepared in pressurized aluminum cylinders with special internal surface treatment using gravimetric method. Analytical methods using gas chromatography-flame ionization detector (GC-FID) coupled with a cryogenic preconcentrator were also developed to verify the consistency of gravimetrically prepared HAP VOCs PRMs. Three different columns installed in the GC-FID were evaluated and compared for the retention times and separation of eighteen target components in a chromatogram. Results show that the HAP VOCs PRMs at 5 nmol/mol were consistent within a relative expanded uncertainty (k=2) of less than 3 % except acrylonitrile (less than 6 %) and the 18 VOCs were stable for 1 year within their associated uncertainties.