• Journal of the Korean GEO-environmental Society
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• v.13 no.4
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• pp.53-59
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• 2012

In this study, strength and durability of a geo-polymer grout material(HIT) was investigated through unconfined compression strength tests(UCS)), scanning electron microscope(SEM), elution tests, and surface observations. UCS tests showed high initial strength and rapid continuous strength increments when compared to labile wasser glass(LW) and space grouting rocket system (SGR) grout materials, which showed strength reduction after 28 days. The higher strength was also reflected in SEM results which showed calcium silicate hydroxide(C-S-H) gels of the dense hydrate range, indicating higher strength and durability. Additionally, elution tests and grout surface observations showed HIT was in good condition and the decrease in weight was minor when under water for six months. LW and SGR showed the grout surface to be constricted and lower durability due to higher weight increase. These results and observations show HIT to be better suited for coastal structural applications than LW and SGR in long terms of strength and durability.

• Journal of Astronomy and Space Sciences
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• v.28 no.1
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• pp.13-16
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• 2011

The $CH_3OH$ $4_2-5_1$ E transition was observed toward the Sgr B2 region, including the Principal Cloud and its surroundings. This methanol transition shows an extended emission along the 2'N cloud, which is believed to be colliding with the Principal Cloud and may trigger the massive star formation in this cloud. This extended methanol emission may also suggest that the 2'N cloud is under shocks. We derive total methanol column density $N(CH_3OH)\;=\;2.9{\pm}0.3{\times}10^{14}\;cm^{-2}$ toward the peak position of the extended emission. The fractional abundance of methanol is about 10.9, relative to the estimated total $H_2$ abundance, which is similar to the methanol abundances in quiet gas phase.

• Proceedings of the Korean Information Science Society Conference
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• 2007.10d
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• pp.494-499
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• 2007

애드 혹 유비쿼터스 컴퓨팅 환경의 가장 큰 특징은 연결의 역동성이다. 노드의 이동으로 인하여 두 노드를 연결하기 위한 경로를 지속적으로 재발견하여야 한다. 한편, 응용 계층에서도 사용자에게 현재의 상황에서 가장 적절한 서비스를 제공하기 위하여 연결된 서비스를 동적으로 재발견/재구성하게 된다. 이러한 환경에서는 이러한 재발견의 부담을 줄이는 것이 중요하다. 발견을 위한 비용이 응용 계층과 네트워크 계층에서 이중으로 발생하는 것을 회피하기 위하여 본 연구에서는 응용 계층의 레이블을 네트워크 계층에서 라우팅의 대상으로 사용하도록 제안한다. 물론 IP 주소에 기반한 라우팅도 동시에 지원한다. 본 연구에서는 IP 주소는 물론이고 응용 계층 레이블을 수용할 수 있는 공유된 라우팅 기법으로서 SGR(shared generic routing)을 제안한다. 시뮬레이션을 통하여 SGR이 발견의 비용을 효과적으로 줄 수 있음을 보였고 리눅스 운영 체제 환경에서 구현하여 실제 적용 가능성을 제시하였다.

• Journal of Welding and Joining
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• v.15 no.2
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• pp.72-80
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• 1997

The spatter generation rate of GMA welding with $CO_2$ gas shielding was measured with the change of welding conditions such as wire feeding rate and welding voltage and then the results were analized with the accompanying changes in metal transfer mode and in bead geometry. The spatter generation rate (SGR) was relatively low not only wit the short circuit transfer but with the truely globular transfer mode. However, the SGR resulted with the mixed mode were consistantly high. The resultant wave pattern of mixed mode was due to the coexistance of short-circuit and globular transfer and characterized by the frequent appearance of instantaneous short circuit. Considering the result of SGR and that of bead geometry, it could be concluded that when the wire feeding rate (or welding current) was either low or high, the optimum bead shape could be obtained along with the low spatter generation. However, in the middle range of wire feeding rate, the optimum bead shape was only obtained in the mixed mode condition resulting in the high spatter generation.

• The Bulletin of The Korean Astronomical Society
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• v.39 no.2
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• pp.115-115
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• 2014

First, We will briefly introduce early science results of AGN observations with KVN and KaVA. KaVA is the combined array of the Korean VLBI network (KVN) and VLBI Exploration of Radio Astronomy (VERA). These include KaVA monitoring of M87, Sgr A* and a few bright blazars and KVN Search for circular polarized Blazars. Furthermore, we will present our future plan of monitoring observation of Sgr A* and M87 with KaVA and Low Radio Power AGN multi frequency polarization survey with KVN. Because of the largeness of their centralsuper-massive black holes, we select them as top-priority sources of our key science program (KSP). The main science goals of the KaVA KSP are (1) mapping the velocity field of the M87 jet and testing magnetically-driven-jet paradigm, and (2) obtaining tightest constraints on physical properties of radio emitting region in Sgr A. High sensitivity achieved through simultaneous multifrequency phase referencing technique of KVN will allow us to explore Low Radio Power AGN cores which build majority of AGNs and therefore are important for undestanding the evolution of AGNs and of their hosts.

• Journal of Microbiology and Biotechnology
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• v.19 no.7
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• pp.718-726
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• 2009

The objective of this study was to develop and validate secondary models that can predict growth parameters of L. monocytogenes Scott A as a function of concentrations (0-3%) of a commercial potassium lactate (PL) and sodium diacetate (SDA) mixture, pH (5.5-7.0), and temperature (4-37DC). A total of 120 growth curves were fitted to the Baranyi primary model that directly estimates lag time (LT) and specific growth rate (SGR). The effects of the variables on L. monocytogenes Scott A growth kinetics were modeled by response surface analysis using quadratic and cubic polynomial models of the natural logarithm transformation of both LT and SGR. Model performance was evaluated with dependent data and independent data using the prediction bias ($B_f$) and accuracy factors ($A_f$) as well as the acceptable prediction zone method [percentage of relative errors (%RE)]. Comparison of predicted versus observed values of SGR indicated that the cubic model fits better than the quadratic model, particularly at 4 and $10^{\circ}C$. The $B_f$and $A_f$for independent SGR were 1.00 and 1.08 for the cubic model and 1.08 and 1.16 for the quadratic model, respectively. For cubic and quadratic models, the %REs for the independent SGR data were 92.6 and 85.7, respectively. Both quadratic and cubic polynomial models for SGR and LT provided acceptable predictions of L. monocytogenes Scott A growth in the matrix of conditions described in the present study. Model performance can be more accurately evaluated with $B_f$and $A_f$and % RE together.

• Journal of Aquaculture
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• v.11 no.4
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• pp.487-493
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• 1998

This study was conducted to investgate the effect of fish meal analogue (FMA) on the growth of Israeli carp, Cyprinus carpio averageing 43g. Leather meal, meat and bone meal, feather meal, squid liver powder, poultry by-product and blood meal were used for ingredient of FMA. Four experimantal diets were formulated to contain 36% crude protein and 15.4 kJ available enery g-1. The percentage of follows ; Diet 1, 100% 3, 60% WFM + 40% FMA (40% FMA) ; Diet 4, 40% WFM + 60% FMA (60% FMA). In this expriment, fingerling Israeli carp averaging 43 g were assigned to each diet treatment. When the experiment was terminated, weigth gain (WG), feed conversion (FC), specific growth rate (SGR) and protein efficiency ratio (PER) were measured respectively. In the experiment, WG, FC, SGR and PER of Diet 2 were not significantly different from those of the control diet (P0.05). And WG, FC and SGR of Diet 3 were not significantly of the control Diet. In Diet 4, WG, FC and PER were not significantly different from those of the control Diet, but SGR was lower than that fo the control Diet. According to the results from this study, it might be possible to replace fish meal protein by FMA up to 60% in fingerling Israeli carp diets.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.2
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• pp.89-94
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• 2001

Sword bean belongs to the subgenus Canavalia in the genus Canavalia. White and reddish varieties in sword bean were tested to obtain the basic information for improving the yield, quality, and cultural environments through the quantitative growth analysis. Growing plants were sampled at intervals of 10 days from 20 days after sowing. Whole plant weight increased during the period of 11-20 days after sowing in both varieties. The weight of each organ between two varieties increased similarly except leaf area. Whole plant weight changed more close to pod weight than any other characters. The leaf areas of both varieties increased from 50 days after sowing, var. white displayed S type curved line but var. reddish displayed slow S type curved line. The SGR of whole plant weight in both varieties had 3 maxima and 2 minima, 3 maxima and first minimum were shown at the same period but the second minimum was shown at different period. Both varieties showed bimodal curved line. All SGR of each organ and leaf area were shown the 2 maxima and 1 minimum in both varieties. The changes of SLA and LAR were not remarkable between two varieties but these were united together with the maximum of whole plant weight and root weight. ULWR and ULWR were shown similar in both varieties. Reddish variety was more prosperous in early growth stage than white variety because SLA, LAR and LWR were high. In surplus weight, both varieties increased rapidly during the period of 111-120 days after sowing that was applicable to the maximum SGR of pod weight. Surplus weight of var. white increased markedly during the same period comparing those of var. reddish.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.1
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• pp.37-43
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• 2012

We have investigated the effect of melatonin (MLT) on specific growth rate (SGR% $day^{-1}$), condition factor (k), gonado-somatic-index (GSI), histological structures of gonads, serum as well as gonadal protein and lipid in Nile tilapia Oreochromis niloticus. MLT treatment in the dose of 25 ${\mu}g/L$ for three weeks reduced SGR% $day^{-1}$ ($0.9{\pm}0.04$) as compared to control ($1.23{\pm}0.026$). The GSI value was significantly (p<0.05) reduced to $1.77{\pm}0.253$ from control where it was $2.56{\pm}0.25$. Serum protein level increased from $9.33{\pm}2.90$ mg/ml (control) to $11.67{\pm}1.45$ mg/ml after MLT treatment while there was depressed serum triglycerides ($86.16{\pm}1.078$ mg/dl) and cholesterol ($126.66{\pm}0.88$ mg/dl) as compared to control values where these were $123.0{\pm}1.23$ mg/dl and $132.0{\pm}1.65$ mg/dl respectively. Histological structure of ovary showed small eggs of early perinucleolus stage after MLT treatment while testicular structure of control and MLT treated fish was more or less similar. It is concluded that exogenous melatonin suppressed SGR% $day^{-1}$, GSI, ovarian cellular activity, protein and lipid biosynthesis, in tilapia suggesting that melatonin is useful in manipulating the gonadal maturity in fishes.

• Fisheries and Aquatic Sciences
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• v.17 no.1
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• pp.75-84
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• 2014

To determine a suitable dietary protein/lipid (CP/CL) ratio in the early juvenile stages of hybrid porgy ($F_1$), female red sea bream (RSB) ${\times}$ male black sea bream, five diets with various CP/CL ratios-60/7, 55/12, 51/17, 46/23, and 41/28-were prepared and provided to juveniles in triplicate. At the smaller juvenile stage, $F_1$, weighing 0.32 g, a significantly higher specific growth rate (SGR) and feed efficiency (FE) were seen with 60/7 and 55/12 diets. However, in RSB weighing 0.26 g, SGR and FE were higher with the 60/7 diet than the other diets at $21^{\circ}C$. At the larger juvenile stage, $F_1$, weighing 3.7 g, there was no significant difference in SGR or FE among the diets, but RSB weighing 4.0 g fed 60/7, 55/12, and 51/17 diets had higher SGR and FE than 46/23 and 41/28 diets at $24^{\circ}C$. Moreover, survival and apparent nutrient retention of $F_1$ at both stages were significantly higher than those in RSB. These results indicate that both $F_1$ and RSB weighing ca. 0.3 g require a higher dietary CP/CL than those weighing ca. 4 g. Additionally, $F_1$ in both trials showed the suitability of a lower dietary CP/CL than RSB, indicating that mass production of $F_1$ juveniles will be more economical than RSB.