• Journal of Korean Society of Water and Wastewater
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• v.11 no.3
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• pp.79-86
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• 1997

The characteristics of wastewater treatment according to operating condition of indirectly aerated fluidized bed filled with sand media were studied experimentally, and the obtained results were as follows; 1. During be operated under the BOD loading rate, $4.5kg-BOD/m^3{\cdot}day$, effluent SS according to the increase of recirulation velocities was gradually decreased. 2. According to the increase of media concentration, sludge convertion rate was gradually increased. 3. Under the same BOD loading rate, according to the increase of recirulation velocities, F/M ratio was gradually increased, however, sludge convertion rate was greatly decreased. On the other hand, inffluent BOD concentration has not an important effect. 4. Under the constant recirulation velocities, according to the increase of BOD loading rate, sludge convertion rate was gradually increased. 5. Under the same BOD loading rate, according to the increase of recirulation velocities, oxygen consumpion rate of microorgnism was gradually increased.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2001.04a
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• pp.95-100
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• 2001

Recently, coated milling cutters are widely used for improving the productivity of cutting processes through high speed cutting and longer tool life. In metal cutting, cutting force increase rate is important factor to diagnose the cutting conditions because the amount of tool wear directly influences the cutting forces. As the cutting length increases, the worn cutter increases the cutting forces. In this study, the effect of coating process of end milling cutter on the cutting performance, especially on the cutting force increase rate, is investigated. The results acquired through the cutting test measuring cutting force increase rate show that not only the injection quantity of $N_2$ and Ar but also mean temperature influence the cutting force increase rate during the end milling process.

• Journal of Technologic Dentistry
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• v.25 no.1
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• pp.143-159
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• 2003

In this study, the data and the Statistical Annual Report of the Korean Dental Technology Association and the yearbook of Health-Welfare Ministry from 1990 to 2002 were surveyed to study and analyze the yearly increase rate and regional distribution rate of the national dental laboratories and dental clinics, the rate of dental laboratories to dental clinics. The purpose of the thesis is to help dental technicians to open the rational and effective dental laboratory which considers the regional condition and the distribution of dental clinics. The result of the study is as follows; 1) The yearly increase rate of overall dental laboratories is 2.01 times to 2002 by the criteria of 1990. The most laboratories was increased in 1995(+94) but the least laboratories was increased in 2000(+13). According to the regional increase rate, Kyounggi Association showed the highest increase rate (7.00 times) but Woolsan Association showed the least increase rate (1.45 times) for the past 5 years. Busan Association had increased by 1.47 times by the criteria of 1990. 2) According to the regional distribution rate of dental laboratories, Seoul area showed the highest distribution rate from the minimum 26.72%(in 2002) to the maximum 35.23%(in 1990) every year, and before 1993, Busan area showed the high distribution rate of 12.49% and Daegu area 12.38%. 3) In the case of the national increase rate, dental clinics had increased by 2.01 times to 2001 by the criteria of 1990 and dental laboratories, whose number was 1,482 in 2002, had increased by 2.01 times to that year. The rate of the national dental laboratories to dental clinics went up an average of 1: 7.57 for 12 years. In 1994, the rate showed the highest 1:7.91 and in 1990, the rate showed the least 1:7.17. 4) The metropolitan rate of dental laboratories to dental clinics showed the average of 1:6.70 for 12 years, and the rate was highest in 1992(1:7.15) and the rate lowest in 1999(1:6.33). 5) The rate of dental laboratories to dental clinics in other areas was 1:9.53, the average of 12 years and was highest in 1991(1:9.97) and was lowest in 1990(1:8.79). (6) The rate of the Korean dental laboratories to dental clinics was 1:7.37 in 2001, the metropolitan rate was 1:6.53 and the rate in other areas was 1:9.10. According to the regional distribution rate, the rate of Kyounggi was highest (1:15.58) and the rate of Daegu was lowest(1:3.03).

• International Journal of Internet, Broadcasting and Communication
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• v.11 no.3
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• pp.87-94
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• 2019

In the study, we show the annual average increasing rate of death bodies in the capital area was 2.1% while the annual average increasing rate of cremated bodies was 4.5%. As the annual average increasing rate of cremated bodies was about 2.1 times higher than the annual average increasing rate of death bodies, the increase rate of cremated bodies contrast to the increase rate of death bodies was relatively high. Also, the cremation rate of the capital area was increased by 9.5% from 80.3% in 2011 to 89.8% in 2017 while the increase rate of cremated bodies was 27.2%(N=21,694 people) from 79,866 people in 2011 to 101,560 people in 2017. Thus, the increase rate of cremated bodies contrast to the increase of cremation rate of the capital area was relatively very high. On the basis of 2017, the utilization rate of public cremation facilities in by capital area was 94.5% in Incheon Metropolitan City, 91.1% in Seoul Metropolitan City, and 20.9% in Gyeonggi-do, which showed huge differences in the utilization rate of public cremation facilities in the jurisdiction area of by capital area. Focusing on the actual state shown in the results of this study above, it would be necessary for Seoul Metropolitan City to carry forward a supply & demand policy of cremation facilities through the extension of cremation furnaces, for Gyeonggi-do to carry forward a policy to build the public cremation facilities focusing on the basic local government in the jurisdiction area, and for Incheon Metropolitan City to enforce the measures for the joint use of cremation facilities with the basic local government in the adjacent Gyeonggi-do jurisdiction area in order to improve the efficiency of the operation of cremation facilities.

• Journal of Biosystems Engineering
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• v.13 no.3
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• pp.59-70
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• 1988

A computer simulation model for rice circulating concurrent-flow dryer was developed and verified by conduction a series of pilot-scale experiment. The effects of design parameter and operating conditions on dryer performance were analyzed by using simulation. The results indicated that the developed model was found suitable for analyzing operating characteristics. The other results from simulation also showed that; 1) an increse in the initial moisture content resulted in an increase in the drying rate and a reduction in the grain temperature and total energy requirements. 2) an increase in the drying air temperature resulted in an increase in the drying rate and grain temperature. 3) an increase in air flow rate resulted in an radical increase in drying rate, fan power requirements and total energy requirements but an radical decrease in final head rice yield. 4) an increase in the bed depth resulted in an increase in fan power requirements and a lowering of the final head rice yield.

• Journal of Environmental Health Sciences
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• v.17 no.2
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• pp.41-47
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• 1991

A study on the effects of volumetric loading rate, surface loading rate and hydraulic. retention time (HRT) for the anaerobic treatment was conducted with the anaerobic fixed-film process using synthetic wastewater at lower temperature than that of conventional anaerobic treatment. The results are as follows 1. Alkalinity and pH value decreased as the hydraulic retention time increased 2. Increase of the volumetric lodaing rate led to increasl of effluent COD concentration and decrease of COD removal efficiency. 3. The removed volumetric loading rate increased linearly according to the increase of the volumrtric loading rate. 4. Similarly, the linear increase of the removed surface loading rate was noticed with an increase of the surface loading rate.

• Journal of Pharmaceutical Investigation
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• v.26 no.4
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• pp.263-271
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• 1996

Sulconazole nitrate(SCN), an imidazole derivative which has been effective in the treatment of dermatophytosis, tinea versicolor and candidiasis, was formulated as a gel containing drug, poloxamer 407, ethanol and propylene glycol. The resulting SCN gels were evaluated with respect to their viscosity, drug release rate, skin permeation rate. The apparent viscosity of SCN gel increased in proportion to poloxamer 407, drug and propylene glycol concentration. In case ethanol was added, the apparent viscosity decreased. The drug release rate of SCN gel increased in proportion to temperature and ethanol concentration. But the drug release rate decreased as the concentration of poloxamer 407 increased. The increase of drug concentration induced nonlinear increase of drug release rate. When propylene glycol was added at the level of 10%, the drug release rate increased but from 15% it decreased. The skin permeation rate decreased in high concentration of poloxamer 407. The skin permeation rate of SCN gel containing 15% ethanol increased about twice than that of gel without ethanol. The increase of drug concentration induced nonlinear increase of skin permeation rate. When propylene glycol was added at the level of 10%, the skin permeation rate increased but from 15% it decreased.

• Animal cells and systems
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• v.6 no.1
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• pp.19-22
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• 2002

Life table studies were conducted in the laboratory for the eulophid gregarious pupal parasitoid, Tetrastichus sp., on Hyphantria cunea Drury at a constant temperature of 28.2$\pm$2$^{\circ}C$, 50-60% RH to evaluate their impact on the host and their potential biological control. Development of immature stage took 20.1$\pm$2.7 d: adult females lived for 23.2$\pm$2.2 (range, 16-27)d and produced a mean of 53.6$\pm$26.6 adult progeny per female, with a sex ratio of 1: 9.5 (M:F). The intrinsic rate of natural increase (r$_{m}$) was 0.178/ female/day; the net reproductive rate (R$_{o}$), 46.74; the capacity for increase (r$_{c}$) 0.177; the finite rate of increase (λ) 1.19/female/day; thus each female contributed 46.74 individuals to the population in a mean generation time of 21.6 d. Biological factors in determining the life history trait variation of the parasitoid were discussed.d.d.d.

• Journal of Urban Science
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• v.8 no.2
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• pp.13-18
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• 2019

Using self-made coil dielectric barrier discharge reactor, the removal efficiency of ethyl acetate under simulated experimental parameters such as initial concentration of waste gas, total flow rate, relative humidity and voltage was investigated. The results show that the degradation rate of ethyl acetate increases with the increase of output voltage. When other conditions remain unchanged, the degradation rate decreases with the increase of initial concentration of ethyl acetate; with the increase of total flow rate, the degradation rate of ethyl acetate decreases; with the increase of relative humidity, the degradation rate first increases and then decreases, and when the relative humidity is 64%, the degradation efficiency is the highest.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.34 no.12
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• pp.59-66
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• 2006

To understand the role of helical geometry on the regression rate enhancement, two competing underlying mechanisms such as turbulence enhancement and swirling motion production were studied by numerical calculations. Experimental results showed that the enhancement of heat transfer rate has the very close relation to the increase in regression rate even though the percentage of increase in heat transfer rate is different from that in regression rate. This discrepancy is presumably due to the change of turbulent flow feature caused by so-called "blowing mass flux" from the fuel surface. In this regard, the results of RANS calculation show that the blowing velocity is responsible for the reduction of the swirl generation and the increase in the turbulent kinetic energy. And the dominancy of one of the mechanisms causes the increase in the regression rate. Meanwhile, the increase in turbulent kinetic energy due to the mixing of blowing flow and free stream flow does not contribute for the enhancement of the heat transfer rate to the surface because the blowing flow pushes boundary layer away from the solid surface.