• 한국축산식품학회지
• /
• 제21권2호
• /
• pp.156-162
• /
• 2001

The quality changes of UHT market milk product were investigated by the season and storage conditions. Throughout the year, standard plate counts(SPC) wasnt increased significantly during storage at 5$\pm$1 and 7$\pm$1$^{\circ}C$ for 10 days. And except for summer, SPC was lower than 20,000 cfu/ml after storage at 10$\pm$1$^{\circ}C$ or 10 days. But SPC was rapidly increased from 3 days at 15$\pm$1$^{\circ}C$, and there was gas forming by yeast growth after storage at 30$\pm$1$^{\circ}C$. Values of pH and titratable acidity of market milk products were 6.49 to 6.71 and 0.155 to 0.16%, respectively. pH and titratable acidity were a lot changes at the temperature over 15$\pm$1$^{\circ}C$, and milk products showed a curd at 30$\pm$1$^{\circ}C$. Carbohydrate of market milk product had little difference throughout the year, whereas fat, protein and total solids of market milk products in autumn showed a little higher value than that of other seasons. There were no changes of milk composition during storage periods, but carbohydrate was decreased a little after storage over 20$\pm$1$^{\circ}C$.

• 한국물환경학회지
• /
• 제29권1호
• /
• pp.81-87
• /
• 2013

Changes of organic carbon after the entrance into dam reservoirs were investigated using water samples collected in May, September, and October in 2010 from the inflow sites and the outlets of four selected dam reservoirs-Soyang, Chungju, Chungju regulation, and Uiam. Increase of refractory dissolved organic carbon (R-DOC) was observed only for large dam reservoirs with long residence times whereas the trend was not found for relatively small reservoirs. The effects of residence times on organic carbon changes were further confirmed by significant positive correlations between monthly residence times and the relative increase of either dissolved organic carbon (DOC) or R-DOC concentrations. Comparison of spectroscopic characteristics of DOC revealed that the changes in the large reservoirs in May might result from in-lake processes. The inflow of terrestrial sources of DOM during storms appears to largely affect the DOC quality of the large reservoirs for the rest of the sampling periods. The mechanism, however, did not fully explain the behaviors of DOC for the small sized reservoirs. Our combined results suggested that both residence time and the input of allochthonous carbon sources might substantially influence the quantity of DOC as well as its quality in dam reservoirs.

• 설비공학논문집
• /
• 제5권3호
• /
• pp.169-178
• /
• 1993

Performance charts of capillary tubes for R-134a are presented. The calculation is based on the one-dimensional, adiabatic flow through capillary tube. The length of capillary tube changes with inlet pressure, mass flux, inlet quality(or subcooling), and inside diameter. The length for R-134a is shorter by 12.5~23% than that for R-12 as mass flux varies, by 13~18.5% as inlet pressure changes, by 15~15.2% as inside diameter changes, and by 3.6~20% as subcooling(or quality) changes. In general, the length for R-134a is shorter than that for R-12 by 10~20%. Pressure drop per unit length for R-134a is greater than that for R-12 since specific volume of R-134a is larger that of R-12 and vapor pressure of R-134a is greater than that of R-12. Flash point of R-134a is ahead of that of R-12.

• 한국수산과학회지
• /
• 제49권6호
• /
• pp.731-736
• /
• 2016

No freshness indicator for fish has yet been established. Thus, we investigated changes over time in mackerel quality in an effort to development useful indicators. Fresh whole mackerel Scomber japonicus were stored at $4^{\circ}C$ immediately after capture and quality changes were evaluated every 3 days for a total of 15 days. Whole fish were divided into ventral parts (VPs) and dorsal parts (DPs); we measured the trimethylamine (TMA) and volatile basic nitrogen (VBN) levels, pH values, and color values in/of these parts. The TMA and VBN levels tended to increase during storage and the TMA changes in VPs were higher than those in DPs. In particular, the VP TMA content attained a maximum of 3.68 mg/100 g at 6 days, and the VBN content attained a maximum of 20.88 mg/100 g at 9 days, suggestive of initial fish spoilage. The pH ranged from 5.99-6.17 over the first 3 days and from 6.17-6.38 from days 6-15. Surface color changes on VPs and DPs were explored. Significant decreases in both VP lightness and yellowness were evident after 3 days. The data suggest that both TMA level and lightness of the color are valuable indicators of freshness in the initial stage of mackerel retail.

• 산업경영시스템학회지
• /
• 제39권1호
• /
• pp.140-152
• /
• 2016

It is very important for the competitiveness and sustainable management of enterprises that the rapid changes in the managerial environments quickly and accurately are responded. For example, the large-scale investment accompanied by bad alternatives in accordance with misunderstanding of the managerial environments yields the huge cost and effort to modify and improve. In firm management, the quality of products and the productivity are influenced by changes of the endogenous factors yielded in manufacturing process and the exogenous factors as market, etc. These changes include not only changes in 4M (man, machine, material, method) but also those in the market, competitors, and technologies in the process of commodification, i.e., first, such disturbances make dispersion of the process big and odd. By Shewhart chart it can be checked that the process monitored is control-in or out. Business administration executes activities for input stabilization by monitoring changes in 4Ms, comparing with the standards, and taking measures for any abnormality. Second, TRM (technology road map) is to prospect product deployment and technological trend by predicting technologies in the competitive environment as the market, and to suggest the future directions of business. So, TRM must be modified and improved according to DR (design review) stages and changes in mass-production like input material change. Therefore, a role of TRM in input stabilization for reducing cost and man-hour is important. This study purposed to suggest that the environment changes are classified into endogenous factors and exogenous factors in production process, and then, quality and productivity should be stabilized efficiently through connection between TRM and input stabilization, and to prove that it is more effective for the display industry to connect TRM with input stabilization rather than to use TRM separately.

• 품질경영학회지
• /
• 제43권1호
• /
• pp.1-10
• /
• 2015

Purpose: It can be said that the 21st century is the age of creativity. However creativity has been relatively less considered in comparison with control and continuous improvement in quality management. How to incorporate creativity into quality management is treated in this paper. Methods: The opposing characteristics of quality and creativity are examined, and the possible outcomes resulted from the conflict are reviewed. Previous researches on managing evolutionary and revolutionary changes are also examined. Results: Quality and creativity require each other although they have incompatible characteristics, and can be incorporated into the innovation cycle. Conclusion: Creative thinking tools such as SIT should be included in the quality training and education for the effective operation of the innovation cycle.

• 환경영향평가
• /
• 제15권1호
• /
• pp.45-52
• /
• 2006

The purpose of this study is to assess spatiotemporal variation of coastal water quality according to time and location changes. For this we developed numerical marine trophic index base on four water quality components (chlorophyll, suspended solids, dissolved inorganic nitrogen and phosphorus) and applied this index to the water quality data measured in the korean coastal zone for the 7-years period from 1997 to 2003. Water quality data are obtained only at selected sites even though they are potentially available at any location. Therefore, in order to estimate spatial variation of coastal water quality, it is necessary to estimate the unknown values at unsampled locations based on observation data. In this study, we used IDW (Inverse Distance Weighted) method to predict water quality components at unmeasured locations and applied marine trophic index to predicted values obtained by IDW interpolation. The results of this study indicate that marine trophic index and spatial interpolation are useful for understanding spatiotemporal characteristics of coastal water quality.

• 대한안전경영과학회지
• /
• 제8권1호
• /
• pp.131-144
• /
• 2006

Quality system management adapted by small and medium enterprises in Kangwon province to enhance the competitiveness was studied. Variance analysis on several questionnaire answers was performed. Motives for acquiring the accreditation, such as product export, adjustment to international trend, enhancement of brand/product recognition, CEO's mind change, and management innovation, have been changed significantly among business types. Mind changes after the accreditations were setting company's first priority on quality, enhanced recognition on compliance of in-house standards and regulations, employee's performance with the recognition of quality. Amongst service problems to maintain the ace reditations were difficulties in maintaining the recognition of the company's finality management, labor increase to maintain the ISO 9000 enforcement team, and financial burden to keep the accreditation. Quality recognition after the accreditations was significantly improved in setting company's first priority on quality, enhanced recognition on compliance of in-house standards and regulations, employee's performance with the recognition of quality.

• 반도체디스플레이기술학회지
• /
• 제22권1호
• /
• pp.59-63
• /
• 2023

Various devices have been emerging as a means of measuring indoor air quality, and among them, there are devices that support real-time remote monitoring through IoT technology and a cloud environment. To improve indoor air quality, based on the results determined by measuring devices, air purifiers or ventilation systems may need to be operated, and temperature and humidity control may be required. In this paper, we propose a design of indoor air quality measuring devices required for indoor air quality evaluation, and of the system needed to control relevant devices to improve indoor air quality through the interaction with the measuring devices. Currently, the servers for the interaction of indoor air quality devices and IoT devices are divided into conventional server type and serverless type, comparing the differences in response time of IoT devices to changes of indoor air quality.

• 한국환경과학회지
• /
• 제26권11호
• /
• pp.1209-1222
• /
• 2017

On June 5, 2008, the "Act on Special Cases Concerning the Simplification of Authorization and Permission Procedures for Industrial Complexes" (Act No. 9106) was enacted. When it was implemented in August 2008, many industrial complex development projects were established, and the number of industrial complexes growth rates of 3-6% during 2003-2007 rose to around 15% in 2008. With the increase in industrial complexes, the environmental impacts of individual projects were examined, but comprehensive regional reviews of environmental impacts were not undertaken. In this study, we determined changes in air quality by applying the industrial complex development plan that completed the consultation at the end of 2010 to assess the comprehensive regional environmental impacts and presented the adequacy review plan for future industrial development plans based on the study's results. When considering these industrial complex development plans, emissions in North Jeolla and South Chungcheong Provinces and Daegu City have increased significantly. Air quality analyses showed that the 24 h mean $SO_2$ concentration in Daegu increased by more than 50% in summer compared to air quality concentrations in summer. The 24 h mean $PM_{10}$ and $NO_2$ concentrations increased by approximately 12 and 30%, respectively, in North Jeolla Province in summer. Areas exceeding the air quality standard for 1 h mean $O_3$ concentration increased by more than $3,500km^2$. Based on the above analysis, changes in air quality should be anticipated through a comprehensive evaluation of long-term development plans. Furthermore, control of air quality in accordance with the development of future industrial complexes is possible.