• Journal of Korean Society of Environmental Engineers
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• v.28 no.11
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• pp.1213-1221
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• 2006

In this study, granular sludge used in an anaerobic process treating brewery waste was inoculated in a laboratory scale of reactor to induce anaerobic ammonium oxidation(ANAMMOX). The reactor was operated with synthetic wastewater, which prepared at 1:1 ratio of $NH_4^+-N$ over $NO_2^--N$. Changes in nitrogen concentration, COD, alkalinity and gas production were analyzed. There are 3 phases of spanning in experimental period according to influent nitrogen concentration. In the Phase 1, each of the concentration of $NH_4^+-N$ and $NO_2^--N$ were increased from 1.91 $gN/m^3{\cdot}d$ to 14.29 $gN/m^3{\cdot}d$. Ammonium nitrogen loading(same as nitrite nitrogen) was 23.81 $gN/m^3{\cdot}d$ in the Phase 2 and 19.05 $gN/m^3{\cdot}d$ in the Phase 3, respectively $NO_2^--N$ has been removed up to 99% during whole period while the removal efficiency of $NH_4^+-N$ was significantly varied. In Phase 2, $NH_4^+-N$ was removed up to 75%. Microorganisms varied temporally through three phases were characterized by 16s rDNA analysis methods. ANAMMOX bacteria were dominantly found in phase 2 when the removal rate of $NO_2^--N$and $NH_4^+-N$ was the highest up to 99% and 75%, respectively. Due to erroneous exposed to air, the removal efficiency of $NH_4^+-N$ was unexpectedly lowered, but ANAMMOX bacteria still existed.

• Journal of Korean Society of Environmental Engineers
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• v.38 no.6
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• pp.279-290
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• 2016

The performance of upflow anaerobic bioelectrochemical reactor (UABE), equipped with electrodes (anode and cathode) inside the upflow anaerobic reactor, was compared to that of upflow anaerobic sludge blanket (UASB) reactor for the treatment of acidic distillery wastewater. The UASB was stable in pH, alkalinity and VFAs until the organic loading rate (OLR) of 4.0 g COD/L.d, but it became unstable over 4.0 g COD/L.d. As a response to the abrupt doubling in OLR, the perturbation in the state variables for the UABE was smaller, compared to the UASB, and quickly recovered. The UABE stability was better than the UASB at higher OLR of 4.0-8.0 g COD/L.d, and the UABE showed better performance in specific methane production rate (2,076mL $CH_4/L.d$), methane content in biogas (66.8%), and COD removal efficiency (82.3%) at 8.0 g COD/L.d than the UASB. The maximum methane yield in UABE was about 407mL/g $COD_r$ at 4.0 g COD/L.d, which was considerably higher than about $282mL/g\;COD_r$ in UASB. The rate limiting step for the bioelectrochemical reaction in UABE was the oxidation of organic matter on the anode surface, and the electrode reactions were considerably affected by the pH at 8.0 g COD/L.d of high OLR. The maximum energy efficiency of UABE was 99.5%, at 4.0 g COD/L.d of OLR. The UABE can be an advanced high rate anaerobic process for the treatment of acidic distillery wastewater.

• Economic and Environmental Geology
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• v.47 no.6
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• pp.589-599
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• 2014

This study selected optimal sites in Myeongsasimni located in west coast of Korea for stratigraphic research containing extreme climate event during quaternary period by spatio-temporal analyses of changes in sedimentary environment and land use employing 1918 topographic map, 2000 digital terrain map, 1976 and 2012 air photographies. The study area shows no significant changes in topographic characteristics that hilly areas with relatively large variations in elevation are distributed over north and south part of the study area, and sand dues are developed along the coast line. Moreover, flat low lying areas are located at the back side of the sand dues. The movement of surface run off and sediment loads shows two major trends of inland direction flow from back sides of sand dunes and outland direction flow from high terrains inland, and the two flows merge into the stream located in the center of the study area. Two sink with individual area of $0.2km^2$ are observed in Yongjeong-ri and Jaryong-ri which are located in south central part and south part of the study area, respectively. In addition, sea level change simulation reveals that $3.4km^2$ and $3.64km^2$ are inundated with 3 m of sea level rise in 1918 and 2000, respectively, and it would contribute to chase sea level change records preserved in stratigraphy. The inundated areas overlaps well with sink areas where it indicates the low lying areas located in south cental and south part of the study area are identical for sediment accumulation. The areas with minimal human impact on sediment records over last 100 years are $3.51km^2$ distributed over central and south part of the study area with the land use changes of mud and rice field in 1918 to rice field in 2012. The candidate sites of $0.15km^2$ in central part and $0.09km^2$ in south part are identified for preferable locations of geologic record of extreme climate events during quaternary period based on the overlay analysis of optimal sedimentary environment and land use changes.

• Korean Journal of Environmental Agriculture
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• v.21 no.1
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• pp.50-56
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• 2002

This experiment was carried out to obtain some information about overwintering, physiological and ecological characteristics of apple snails. Another purpose of this experiment was to characterize an appetite for rice plants by apple snails and to elucidate their choice of fresh green ones (vegetables, some other crops, weeds in rice fields). The freshwater snails were found with higher population at sites abundant organic compounds such as plant debris and at regions with high temperature. They also prefer calcium-rich water. This is a naturally occurring process. Apple snails were exceptionally veil-adapted to the south regions of Korea, especially Janghang, Jangseong and Haenam, even if the temperature of winter season is cold below 0$^{\circ}C$. Apple snails were not very selective in their food choice and eat almost everything available in their environment. A snail have something called a radula in its mouth for grinding up its food. A apple snail also chews on fruits and young succulent plant barks. In case of reproduction. apple snails deposit about 157$\sim$784 (average of 321 eggs) milky white to pale orange colored eggs above the waterline. In approximately every 22.4 seconds a new egg appears. The total time needed to deposit a egg mass varies from 58 minutes$\sim$4 hours 13 minutes. Apple snails reproduct actively from May to June and from September to October. An appetite of apple snails for rice plants was the different depending on their size and glowing stage for rice plants. Apple snails had a great appetite of rice plants as well as dropwort, tomato, cabbage, radish, aquatic plants etc. They preferred to eat young rice plants and drastically quit eating rice plants of over 40 cm in height. Thus considering the food preference of apple snail for various plants including rice, they were thought to be a potentially strong predator in fields, especially, at regions with warmer winter.

• Korean Journal of Environmental Agriculture
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• v.27 no.1
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• pp.27-34
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• 2008

To effectively treat the domestic sewage that was produced on a small-scale in farming and fishing village in order to encourage an ecologically friendly environment, a small-scale sewage treatment apparatus using natural purification methods that consisted of an aerobic and an anaerobic plots were constructed. The efficiency of sewage treatment according to the sewage loading was investigated to obtain the optimum sewage loading in small-scale sewage treatment apparatus. Removal rate of pollutants according to the sewage loading were in the order of $150\;Lm^{-2}day^{-1}{\fallingdotseq}300\;Lm^{-2}day^{-1}>600\;Lm^{-2}day^{-1}$. Therefore, the optimum sewage loading was 300 L m-2 day-1. Under the optimum sewage loading, removal rate of BOD, $COD_{Mn}$, turbidity, T-N and T-P were 99, 94, 99, 49 and 89%, respectively. However, to satisfy the water quality standard in effluent in small-sclae sewage treatment apparatus for domestic sewage treatment, the low removal efficiency of T-N and T-P must be improved. So to improve the removal rate of T-N and T-P, the efficiency of sewage treatment according to the improved sewage treatment process such as, re-treatment at aerobic plot, anaerobic condition of aerobic plot, changing the filter media sizes and the depths in anaerobic plot, and also addition of oyster shells to filter media at anaerobic plot were investigated. In case of 150 cm depth in anaerobic plot with filter medium A (effectivity particle size 1.50 mm) and addition of oyster shells to filter media at anaerobic plot, removal rate of T-N and T-P in both plots were increased by 10 and 3%, and 14 and 7% in comparison with 100 cm depth in anaerobic plot with filter medium B(effectivity particle size 0.95 mm), respectively. The optimum improved sewage treatment process in small-scale sewage treatment apparatus were 150 cm depth in anaerobic plot with filter medium A and addition of oyster shells to filter media at anaerobic plot.

• Analytical Science and Technology
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• v.13 no.4
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• pp.494-503
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• 2000

A 21-residue peptide corresponding to amino acids 84-104 of $p16^{INK4A}$, the tumor suppressor, has been synthesized and its structure was studied by Circular Dichroism, $^1H$ NMR spectroscopy and molecular modeling. A p16-derived peptide (84-104 amino acids) forming stable complex with CDK4 and CDK6 inhibits the ability of CDK4/6 to phosphorylate pRb in vitro, and blocks cell-cycle progression through G1/S phase as shown in the function of the full-length p16. Its NMR spectral data including NOEs, $^3J_{NH-H{\alpha}}$ coupling constants, $C_{\alpha}H$ chemical shift, the average amplitude of amide chemical shift oscillation and temperature coefficients indicate that the secondary structure of a p16-derived peptide is similar to that of the same region of full-length p16, which consists of helix-turn-helix structure. The 3-D distance geometry structure based on NOE-hased distance and torsion angle restraints is characterized by ${\gamma}$-turn conformation between residues $Gly^{89}-Leu^{91}$(${\varphi}_{i+1}=-79.8^{\circ}$, ${\varphi}_{i+1}=60.2^{\circ}$) as evidenced in a single crystal structure for the corresponding region of p18 or p19, but is undefined at both the N and C termini. This compact and rigid ${\gamma}$-turn region is considered to stabilize the structure of p16-derived peptide and serve as a site recognizing cyelin dependent kinase, and this well-defined ${\gamma}$-turn structure could be utilized for the design of anti-cancer drug candidates.

• Broadcasting and Media Magazine
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• v.11 no.4
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• pp.104-117
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• 2006

In this Paper, we analyze the application of Interactive Data Broadcasting in DMB(Digital Multimedia Broadcasting) in the accordance with convergence of service and technology. With the acceleration of digital convergence in the Ubiquitous period substantial development of digital media technology and convergence of broadcasting and telecommunication industry are being witnessed. Consequently these results gave rise to newly combined-products such as DMB(Digital Multimedia Broadcasting), WCDMA(Wide-band code division multiple access), Wibro(Wireless Broadband Internet), IP-TV (Internet protocol TV) and HSDPA(High speed downlink packet access). The preparatory stage for the implementation of Interactive Data Broadcasting Service will be reached by the end of December, 2006. DMB is the first result of a successful convergence service between Broadcasting and Telecommunication in new media era. Multimedia technology and services are the core elements of DMB. The Data Broadcasting will not only offer various services of interactive information such News, Weather, Broadcasting Program etc, but also be linked with characteristic function of mobile phone such as calling and SMS(Short Message Service) via Return Channel.

• The Journal of Korean Society for Radiation Therapy
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• v.16 no.2
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• pp.33-41
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• 2004

Purpose : Film has been the primary tool in coincidence testing between the light field and the radiation field, which constitutes the quality assurance list of a linear accelerator. But there is a great chance of errors being different among the observer when using film. Thus this study set out to use the BIS(Beam Image System) in addition to film in comparing and evaluating coincidence results between the two fields and in searching for the improvement measures. Materials & Methods : Photon beam of 6 and 15MV was exposed to film and the BIS using a linear accelerator. The light and radiation fields were each $50{\times}50,\;100{\times}100,\;and\;200{\times}200mm^2$. The gantry angle was $0^{\circ}$ when using film and $0^{\circ}\;and\;270^{\circ}$ when using the BIS. The devices adopted to test coincidence between the two fields were a ruler and film scanner when using film. With the BIS, the width of the scanned light and radiation fields was measured for errors with setting the X and Y axis. Results : The visual measurements of the observer with film resulted that the radiation field was bigger than the light field and that their maximum error was 1.9mm. The results were the same with the measurements using the film scanner except for the average error, which was less than 1.9mm. On the contrary, the measurements using the BIS showed that the light field was bigger than the radiation field at the gantry angle of $0^{\circ}\;and\;270^{\circ}$. The maximum error was 0.96mm, and the error range was $<{\pm}2mm$ both in the X and Y axis. The average error of ${\Delta}X$, Y was the smallest in the order of the visual film measurements, film scanner measurements, and BIS measurements Conclusion . This requires a careful measurement for accurate quality assurance since errors are much different according to each observer that tests coincidence between visual fields with film. And an observer needs to use another image device or develop a measuring device of his own if it seems necessary for accurate measurements.

• The KIPS Transactions:PartA
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• v.12A no.2 s.92
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• pp.95-102
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• 2005

The Newton-Raphson iterative algorithm for finding a floating point reciprocal which is widely used for a floating point division, calculates the reciprocal by performing a fixed number of multiplications. In this paper, a variable latency Newton-Raphson's reciprocal algorithm is proposed that performs multiplications a variable number of times until the error becomes smaller than a given value. To find the reciprocal of a floating point number F, the algorithm repeats the following operations: '$'X_{i+1}=X=X_i*(2-e_r-F*X_i),\;i\in\{0,\;1,\;2,...n-1\}'$ with the initial value $'X_0=\frac{1}{F}{\pm}e_0'$. The bits to the right of p fractional bits in intermediate multiplication results are truncated, and this truncation error is less than $'e_r=2^{-p}'$. The value of p is 27 for the single precision floating point, and 57 for the double precision floating point. Let $'X_i=\frac{1}{F}+e_i{'}$, these is $'X_{i+1}=\frac{1}{F}-e_{i+1},\;where\;{'}e_{i+1}, is less than the smallest number which is representable by floating point number. So, $X_{i+1}$ is approximate to $'\frac{1}{F}{'}$. Since the number of multiplications performed by the proposed algorithm is dependent on the input values, the average number of multiplications per an operation is derived from many reciprocal tables $(X_0=\frac{1}{F}{\pm}e_0)$ with varying sizes. The superiority of this algorithm is proved by comparing this average number with the fixed number of multiplications of the conventional algorithm. Since the proposed algorithm only performs the multiplications until the error gets smaller than a given value, it can be used to improve the performance of a reciprocal unit. Also, it can be used to construct optimized approximate reciprocal tables. The results of this paper can be applied to many areas that utilize floating point numbers, such as digital signal processing, computer graphics, multimedia scientific computing, etc.

• Applied Biological Chemistry
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• v.41 no.7
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• pp.533-538
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• 1998

In order to gain fundamental information on the utilization of lipids as energy source in mud-skipper, muscle lipids and their fatty acid composition were investigated with respect to life cycle-maturation (Aug), before-hibernation (Nov), and after-hibernation (Apr). Crude and neutral lipid were found to decrease from 1.2, 68.3% (Aug) via 0.7, 53.8% (Nov) to 0.4, 42.6% (Apr), respectively, whilst phospholipids and glycolipids increased from 29.5 and 2.2% (Aug) to 52.1 and 5.3% (Apr), respectively. In neutral lipids, TG contents gradually decreased from 53.8% (Aug) via 33.6% (Nov) to 23.1% (Apr), while FFA and sterol contents increased from 13.5 and 14.2% (Aug) to 22.3 and 24.5% (Apr), respectively. In phospholipids, PC content decreased from 61.2% (Aug) to 50.6% (Apr), while changes in PS and PE contents, as a whole, showed the opposite trends. In neutral lipids, the levels of some fatty acids such as 16:0, 16:1, 18:0, 18:1 and 20:5 $({\omega}3)$ were analyzed to be high, with the 20 : 5 being predominant, and the levels of saturated and monoene-acids gradually decreased, while polyene-acids increased in before and after hibernation. In before hibernation, 16:0, 16:1, 18:1 mainly decreased but 18:2, 18:3 $({\omega}3)$ and most of saturated and monoene acids such as 14:0, 14:1, 16:1, 18:0, 18:1 slightly decreased in after hibernation. From these findings, it was suggested that those fatty acids decreased during hibernation were used as a energy source, particularly 16:1 and 18:1 being most preferentially used. In phospholipids, the levels of 16:0, 18:0, 20:5 $({\omega}3)$, 22:5 $({\omega}3)$ and 22:6 $({\omega}3)$ were found to be high. Throughout the life cycle, the levels of monoene-acids in phospholipids stayed constant, whilst those of 18:2, 18:3 $({\omega}3)$ and saturated acids such as 16:0, 18:0 were found to be decreased gradually in before and after hibernation, whereas those for the high degree of polyene-acids such as 20:4 $({\omega}6)$, 20:5 $({\omega}3)$, 22:5 $({\omega}3)$, 22:6 $({\omega}3)$ increased, particularly 20:4 $({\omega}6)$, 20:5 $({\omega}3)$ being most increased.