• Proceedings of the Korean Magnestics Society Conference
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• 2003.12a
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• pp.108-108
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• 2003

• Journal of Microbiology and Biotechnology
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• v.31 no.3
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• pp.429-438
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• 2021

Bacterial cellulose (BC) is widely used in the food industry for products such as nata de coco. The mechanical properties of BC hydrogels, including stiffness and viscoelasticity, are determined by the hydrated fibril network. Generally, Komagataeibacter bacteria produce gluconic acids in a glucose medium, which may affect the pH, structure and mechanical properties of BC. In this work, the effect of pH buffer on the yields of Komagataeibacter hansenii strain ATCC 53582 was studied. The bacterium in a phosphate and phthalate buffer with low ionic strength produced a good BC yield (5.16 and 4.63 g/l respectively), but there was a substantial reduction in pH due to the accumulation of gluconic acid. However, the addition of gluconic acid enhanced the polymer density and mechanical properties of BC hydrogels. The effect was similar to that of the bacteria using glycerol in another carbon metabolism circuit, which provided good pH stability and a higher conversion rate of carbon. This study may broaden the understanding of how carbon sources affect BC biosynthesis.

• Journal of the Semiconductor & Display Technology
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• v.22 no.3
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• pp.8-13
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• 2023

High bandwidth memory a core technology of the future memory semiconductor industry, is attracting attention. Temporary bonding and debonding process technology, which plays an important role in high bandwidth memory process technology, is also being studied. In this process, total thickness variation is a major factor determining wafer performance. In this study, the reliability of the equipment measuring total thickness variation is identified, and the servo motor settling, and wafer total thickness variation measurement accuracy are analyzed. As for the experimental variables, vacuum, acceleration time, and speed are changed to find the most efficient value by comparing the stabilization time. The smaller the vacuum and the larger the radius, the longer the settling time. If the radius is small, high-speed rotation performance is good, and if the radius is large, low-speed rotation performance is good. In the future, we plan to conduct an experiment to measure the entire of the wafer.

• Journal of Mechanical Science and Technology
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• v.17 no.5
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• pp.718-725
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• 2003

The present study addresses the distortion of the compression wave reflected from an open end of a shock tube. An experiment is carried out using the simple shock tube with an open end Computational work is also performed to represent the experimented flows. The second-order Total Variation Diminishing scheme is employed to numerically solve the unsteady, axisy-mmetric, inviscid, compressible governing equations. Both the experimented and predicted results are in good agreement. The generation and development mechanisms of the compression wave, which Is reflected from the open end of the shock tube, are obtained in detail from the present computations. The effect of size of the baffle plate at the open-end that causes the reflection of the incident expansion wave is found negligible. A good correlation is obtained for transition of the reflected compression wave to a shock wave inside the tube. The present data show that for a given wave length of the incident expansion wave the transition of the reflected compression wave to a shock wave can be predicted with good accuracy.

• Fibers and Polymers
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• v.4 no.3
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• pp.124-128
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• 2003

Dark brown Alpaca fiber was reduced in shade via selective bleaching with peroxide. Two selective oxidative bleaching methods were tested on alpaca top to assess their effectiveness for color removal and fiber quality properties. Color change, bundle strength, weight loss, fiber diameter, surface modification, dye-ability and dye wash fastness were assessed for both methods and compared with the original brown top. Bleach method 1 (BL-I) showed little surface modification, 5.8% weight loss and 2.4% strength loss. D1925 yellowness index was reduced to 74.3 from 83.1 and provided a good base for the dyeing of medium to deep shades. Bleach method 2 (BL-II) displayed considerable surface modification, 7.8% weight loss and 18% strength loss. BL-II also resulted in a mean diameter reduction of 1.9 micron during bleaching. Yellowness was reduced to 64.5 from 83.1 and provided a very good base for the dyeing of medium to deep shades. BL-I showed better exhaustion of the premetallised dye Lanaset Violet B than BL-II. Wash fastness for BL-II was 1 grey scale unit poorer than BL-I. BL-II showed far better color clarity at pale depths however the wash fastness of the finished product was not good enough to maintain the depth or clarity of the color. BL-I showed poorer clarity of color but exhibited better wash fastness results.

• Corrosion Science and Technology
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• v.9 no.6
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• pp.247-253
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• 2010

The characteristics of selective oxidation prior to hot-dip galvanizing with the annealing atmosphere dew point and chemical composition in dual-phase steels and their effect on the inhibition layer formation relevant to coating adhesion have been studied using a combination of electron microscopic and surface analytical techniques. The annealed and also galvanized samples of 3 kinds of Si/Mn ratios with varied amounts of Si addition were prepared by galvanizing simulator. The dew point was controlled at soaking temperature $800^{\circ}C$ in 15%$H_2$ -85%$N_2$ atmosphere. It was shown that good adhesion factors were mainly uniformity of oxide particle distribution of low number density and low Si/Mn ratio prior to hot-dip galvanizing. Their effect was the greatly reduced coating bare spots and the formation of uniform inhibition layer leading to good adhesion of Zn overlay. The mechanism of good adhesion is suggested by two processes: the formation of inhibition layer on the oxide free surface uncovered with no $SiO_2$-containing particles in particular, and the inhibition layer bridging of oxide particles. The growth of inhibition layer was enhanced markedly by the delayed reaction of Fe and Al with the increase of Si/Mn ratio.

• Journal of Technologic Dentistry
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• v.11 no.1
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• pp.23-34
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• 1989

The great sudenn change of circle of dental laboratory technology brought mary discord between the new growing environmental group and the old group, In order to know the satisfactory degree of dental laboratory heads about all dental College, This Study was conducted for 49 detal technicians who graduated from junior laboratory heads in Seoul and Kyoung Gi area. The results are abtained as follow- 1. By age The degree of Satisfaction of items about all graduate dental technician were "41$\sim$45 age" group 26.53%), "46$\sim$50 age" group 22.45%, "36$\sim$40 age" group 18.36%, "31$\sim$35 age" group 12.24%, "51$\sim$55 age" group and "56$\sim$60 age" group 8.16% 60$\sim$age group 4.08% in order. 2. By Job Career. The Highest degree item out of Satisfaction about all graduated dental dental technician was 21$\sim$25 years group 28.5%, 16$\sim$20 years 20.4%, 11$\sim$15 years group 12.24%, 26$\sim$20%, 6$\sim$10 years group 4.08%, below 5 years group 2.04% in order. 3. By managing term of respondent's dental laboratory. The Satisfactory degree of items about all gradate technician were 7$\sim$10 years group 36.73% over 15 years group 22.45%, 11$\sim$14 years group 20.41%, 3$\sim$6 years group 14.29% below 2 years group 6.12% in order 4. By dental technician number of respondent's dental laboratory. The satisfactory degree intems about man were as follow; 6$\sim$9 persons group is 42.86 % The Satisfactory degree items about woman were one persons group in 34.69% 5. By born place The dental laboratory heads mean of inters about all dental technician were Seoul group 20.64 %, Kyoung Gi 17.20 %, Jen Nam group 14.99 % Chung Nam 9.5%in order 6. The satisfactory degree of items about all graduate dental technician were neither good nor bad group 32.65%, bad 6.12%, By ability of adaptaton, The satisfactory degree items about man were neither good nor bad group 42.86%, bad group 40.82%. The satisfactory degree of items about woman were neither good nor bad group 40.82% bad group 36.73%. 7. By sincerity. The satisfactory degree of items about man dental technician who graduated from Junior College were neither good nor bad group 52.02%, bad group 4.08, The satisfactory degree about woman dental technician graduated from Junior College were neither good nor bad group 42.86%, bad group 6.12%. 8. By ability of basical of items about man were bad group 40.82 %. The satisfactory degree about woman were 46.94%. 9. By cooperation relation ship. The satisfactory degree of items about man were neither good nor bad group 42.86%, bad group 10.20%. The satisfactory degree about woman were neither good nor bad group 42.86%, bad group 10.20 %. 10. By ability of work. The satisfactory degree of items about man were neither good nor bad group 48.98%, bad group 4.08%. The satisfactory degree about woman were neither good nor bad group 42.86%, bad group 6.12 %. 11. By the curriculum of the dental technician. The satisfactory degree of items about man were neither good nor bad group 67.35%, bad group 2.04%, The satisfactory degree about woman were neither good nor bad group 61.22%, bad group 6.12%. 12. By occupational satisfaction. The satisfactory degree of items about all graduate dental technician were fatisfied group 14.29%. By the out look of employment. The satisfactory degree of items about man greduate dental technician were neither good nor bad group 34.69 %, bad group 10.20%, about woman graduate dental technician were neither good nor bad group 44.90%, bad group 10.20%, Their employment prospect is not so bright or oprimistic due to the glut supply by graduates in the job-seeking market 13. The satisfactory rate on the artificial dental manufacturing world in terms of effects produced by juror College graduate dental technicians shared good group 40.82% bad group 2.04% 14. By cognition of the number of graduate dental technician. The satisfactory degree of dental laboratory heads about man graduate dental technician were too many group 38.78%, few group 6.12% about woman graduated dental technician were neither good nor bad group 30.6% few group 10,20%, The employment opportunities for the artifical dental technicians are getting decreased because of their excessive cumber in supply 15. The opinion regarding the initial salary. ranging from \160,000 to \200,000 for the junior college graduate dental technicians shared 57.14%. The top ratio, while the satisfaction reate on the academic study period of "3-year" group shared 22%, also the top ratio. 16. The improvement policy and prblematic issues presonted by the owner and operatore of atriticial dental manufacturing plants are as shown below First; The viewpoint that they contribute to the improvement of people's oral health in terms of their mission as artificial dental technicians. Second: The cultivation of basic technical ability to cope with clinical practice upon graduation Third; They require guidance in study and research in their filed of profession, that tray may beable to estaclish a from theory.

• Proceedings of the Korean Vacuum Society Conference
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• 1999.07a
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• pp.160-160
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• 1999

To reduce the fouling of heat exchangers, the plasma polymerized films was coated on the heat exchangers, and an effect of plasma polymerized film on fouling of heat exchangers was investigated. Monomer and reactive gases were used as the precursors of plasma polymerization. Plasma polymerized films were deposited with process parameters of pressure, power, and ratio of gases. Plasma polymerized films could be served as functional layers of good wettability and high resistance to corrosion. Wettability of plasma polymerized film could be controlled by the ratio change gas mixture. Hydrophilicity of plasma polymerized films on heat exchanger in air conditioner can provide improvement in performance of heat exchanger which results from good water drainage, decrease of pressure drop. DC-plasma polymerized films improve resistance to corrosion whcih is related to deposit formation in heat exchangers. The difference in the build up of fouling deposits between bare substrate and plasma polymerized substrate was investigated by scanning electron microscopy (SEM). An effect of plasma polymerized film on fouling of heat exchangers was discussed in terms of surface properties such as wettability, surface chemical state.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.11
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• pp.4311-4330
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• 2015

Cloud computing has become a new paradigm by enabling on-demand provisioning of applications, platforms or computing resources for clients. Workflow scheduling has always been treated as one of the most challenging problems in clouds. Commercial clouds have been widely used in scientific research, such as biology, astronomy and weather forecasting. Certainly, it is very important for a cloud service provider to pursue the profits for the commercial essence of clouds. This is also significantly important for the case of providing services to workflow tasks. In this paper, we address the issues of workflow scheduling in commercial clouds. This work takes the communication into account, which has always been ignored. And then, a topology-based workflow-scheduling algorithm named Resource Auction Algorithm (REAL) is proposed in the objective of getting more profits. The algorithm gives a good performance on searching for the optimum schedule for a sample workflow. Also, we find that there exists a certain resource amount, which gets the most profits to help us get more enthusiasm for further developing the research. Experimental results demonstrate that the analysis of the strategies for most profits is reasonable, and REAL gives a good performance on efficiently getting an optimized scheme with low computing complexity.

• Archives of design research
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• v.16 no.4
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• pp.413-422
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• 2003

In the early 20th century, the efforts for design standards for industry and the new aesthetic of Functionalism began from the Deutcher Werkbund, an English German Association of Craftsmen. In the similar vein, the Bauhaus, founded in 1919 at Weimar, provided the definition of Good Design, as a contemporary concept, that combines art with technology. From 1950 to 1955, the modern usage of the term 'Good Design' was derived from a series of exhibitions and consumer education programs conducted by the MOMA(Museum of Modern Art, New York). The mission was to bring modern design to the attention of the general public. From the second half of the 20th century, many specialists in different areas, such as designers, manufacturers, enterprises, and scholars, began to give various definitions of 'Good Design'. That's why it could be interpreted and applied to unique and various methods by them. Meanwhile, Rams and Norman argued that the Good Design has to be not only considered within function, aesthetic, technology, etc, but also interpreted from both the physical and psychological point of views. Accordingly, this study tried to find out the historical investigation and the definition of Good Design in detail, and to figure out that the user-centered design from both physical and psychological approaches is eventually synonymous to 'Good Design'.