• Journal of Korean Society of Environmental Engineers
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• v.34 no.5
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• pp.295-303
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• 2012

Removal of total nitrogen (T-N) and total phosphorus (T-P) was evaluated in a DEPHANOX process by adding Al(III) to the separator to maintain T-P in the final effluent below 0.2 mg/L. pH in each reactor was maintained 7~8 after addition of Al(III) to the levels of 5, 10, 15 mg/L. The removal efficiency of COD and T-N decreased at higher Al(III) dose, but T-P removal efficiency increased from 76.28 to 84.02, 94.66% at Al(III) dose of 5, 10, 15 mg/L, respectively. T-P in effluent showed 0.17 mg/L at Al(III) dose of 15 mg/L. Minimum 15 mg/L of Al(III) was required to maitain T-P below 0.2 mg/L in the final effluent.

• Smart Structures and Systems
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• v.15 no.3
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• pp.505-522
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• 2015

Variation of temperature is a primary environmental factor that affects the behavior of structures. Therefore, understanding the mechanisms of normal temperature-induced variations of structural behavior would help in distinguishing them from anomalies. In this study, we used the structural health monitoring data of the Shanghai Yangtze River Bridge, a steel girder cable-stayed bridge, to investigate the mechanisms of thermally induced vertical deflection ($D_T$) at mid-span of such bridges. The $D_T$ results from a multisource combination of thermal expansion effects of the cable temperature ($T_{Cab}$), girder temperature ($T_{Gir}$), girder differential temperature ($T_{Dif}$), and tower temperature ($T_{Tow}$). It could be approximated by multiple linear superpositions under operational conditions. The sensitivities of $D_T$ of the Shanghai Yangtze River Bridge to the above temperatures were in the following order: $T_{Cab}$ > $T_{Gir}$ > $T_{Tow}$ > $T_{Dif}$. However, the direction of the effect of $T_{Cab}$ was observed to be opposite to that of the other three temperatures, and the magnitudes of the effects of $T_{Cab}$ and $T_{Gir}$ were found to be almost one order greater than those of $T_{Dif}$ and $T_{Tow}$. The mechanisms of the thermally induced vertical deflection variation at mid-span of a cable-stayed bridge as well as the analytical methodology adopted in this study could be applicable for other long-span cable-stayed bridges.

• Journal of the Korea Convergence Society
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• v.10 no.8
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• pp.9-14
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• 2019

Currently, with the success of 5G commercialization, a server system that integrates various Internet public safety services should be developed. In this paper, we developed a public safety integrated server, which is an IoT platform connecting IoT device and IoT gateway based on IP PBX. This server is based on embedded OS and various IoT services are executed in one system and call processing / broadcasting server function that processes emergency call and emergency broadcasting in public places is built in. This system collects IoT sensor data and emergency bell information and automatically sends out emergency alarms, emergency evacuation broadcasts, etc. at an accident site in an emergency situation, and transmits the daily information to the upper IoT service server, Provide public safety management services.

• Journal of applied mathematics & informatics
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• v.31 no.1_2
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• pp.199-209
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• 2013

In this paper, we study the oscillation problem of the following higher-order neutral differential equation with positive and negative coefficients and mixed arguments $$z^{(n)}(t)+q_1(t)|x(t-{\sigma}_1)|^{\alpha-1}x(t-{\sigma}_1)+q_2(t)|x(t-{\sigma}_2)|^{\beta-1}x(t-{\sigma}_2)=e(t)$$, where $t{\geq}t_0$, $z(t)=x(t)-p(t)x(t-{\tau})$ with $p(t)$ > 0, ${\beta}>1>{\alpha}>0$, ${\tau}$, ${\sigma}_1$ and ${\sigma}_2$ are real numbers. Without imposing any restriction on ${\tau}$, we establish several oscillation criteria for the above equation in two cases: (i) $q_1(t){\leq}0$, $q_2(t)>0$, ${\sigma}_1{\geq}0$ and ${\sigma}_2{\leq}{\tau}$; (ii) $q_1(t){\geq}0$, $q_2(t)<0$, ${\sigma}_1{\geq}{\tau}$ and ${\sigma}_2{\leq}0$. As an interesting application, our results can also be applied to the following higher-order differential equation with positive and negative coefficients and mixed arguments $$x^{(n)}(t)+q_1(t)|x(t-{\sigma}_1)|^{\alpha-1}x(t-{\sigma}_1)+q_2(t)|x(t-{\sigma}_2)|^{\beta-1}x(t-{\sigma}_2)=e(t)$$. Two numerical examples are also given to illustrate the main results.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.3
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• pp.325-337
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• 2003

This study was designed to determine the distribution of trans fatty acids (tFAs) isomers of Processed foods commonly consumed in Korea. The tFAs positional isomers were analyzed using GC/MS spectrometer with HP-23 cis/trans FAME, capillary column (50m $\times$ 0.20 mm, id., 0.2 ${\mu}{\textrm}{m}$ film thickness) for 41 food samples. TFAs isomers were identified by comparing retention time with standards and GC/MS spectrum. In margarines, the content of tFAs ranged from 4.0% to 25.16% and the most abundant positional isomer of tFAs was C18:1 $\Delta$9t. In oils and fats, lards contained higher levels of tFAs (5.70~16.54%) than shortenings (6.77~10.55%). Shortenings contained higher levels of C18:1 $\Delta$9t (3.1~5.1%) than lard (1.6~4.3%), but corn oils had no tFAs. In seasonings, mayonnaise had no C16:1 $\Delta$9t, whereas C18:3t was detected. The content of tFAs in confectioneries was wide (16.20~52.16%). Among them, instant popcorns contained the highest amount of tFAs. Milk and dairy products showed even distribution of tFAS such as C18:1t, C18:2t, and C18:3t. Predominant tFAS isomer of condensed milk and ice cream was C16:1 $\Delta$9t. Frozen french fries and fried chicken contained higher levels of C18:1$\Delta$9t (9.4%), whereas grilled pork (jowl) had no C18:1 $\Delta$9t. The amount of tFAs per serving size was the highest in popcorn, followed by frozen pizza, frozen french fries, fried chicken, and bakeries.

• Asian-Australasian Journal of Animal Sciences
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• v.9 no.3
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• pp.309-313
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• 1996

This experiment was carried out to investigate the effect of rumen-protected lysine (RPLys) on growth rate, feed efficiency and plasma amino acid concentrations in sheep. RPLys was supplemented at the level of 0% ($T_1$), 0.2% ($T_2$) and 0.4% ($T_3$) of total DMI with 24 sheep in a 56 day feeding trial. The results are summarized as follows: 1. live weight gain of sheep in groups $T_1$, $T_2$ and $T_3$ was 219, 216 and 244 g/d, and was significantly (p < 0.05) higher for $T_3$ through the entire experiment. 2. Feed intake was not affected by RPLys supplementation. 3. The group fed $T_3$ had a significantly (p < 0.05) better feed efficiency than the groups fed $T_1$ and $T_3$. The response of $T_3$ was higher in growing period II of feeding low protein basal diet than in period I. 4. Plasma lysine concentrations tended to be higher with supplementing RPLys, but there were no differences between $T_2$ and $T_3$. 5. Supplementing RPLys in the diets increased plasma concentrations of arginine, asparagines, threonine, serine, valine and leucine compared with sheep receiving no RPLys. In contrast, plasma histidine was lower in sheep fed the supplementing RPLys than fed the diet $T_1$ with significant (p < 0.05) difference.

• The Mathematical Education
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• v.26 no.1
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• pp.41-45
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• 1987

In this paper, we give several fixed point theorems in a complete metric space for two multi-valued mappings commuting with two single-valued mappings. In fact, our main theorems show the existence of solutions of functional equations f($\chi$)=g($\chi$)$\in$S$\chi$∩T$\chi$ and $\chi$=f($\chi$)=g($\chi$)$\in$S$\chi$∩T$\chi$ under certain conditions. We also answer an open question proposed by Rhoades-Singh-Kulsherestha. Throughout this paper, let (X, d) be a complete metric space. We shall follow the following notations : CL(X) = {A; A is a nonempty closed subset of X}, CB(X)={A; A is a nonempty closed and founded subset of X}, C(X)={A; A is a nonempty compact subset of X}, For each A, B$\in$CL(X) and $\varepsilon$>0, N($\varepsilon$, A) = {$\chi$$\in$X; d($\chi$, ${\alpha}$) < $\varepsilon$ for some ${\alpha}$$\in$A}, E$\sub$A, B/={$\varepsilon$ > 0; A⊂N($\varepsilon$ B) and B⊂N($\varepsilon$, A)}, and (equation omitted). Then H is called the generalized Hausdorff distance function fot CL(X) induced by a metric d and H defined CB(X) is said to be the Hausdorff metric induced by d. D($\chi$, A) will denote the ordinary distance between $\chi$$\in$X and a nonempty subset A of X. Let R$\^$+/ and II$\^$+/ denote the sets of nonnegative real numbers and positive integers, respectively, and G the family of functions ${\Phi}$ from (R$\^$+/)$\^$s/ into R$\^$+/ satisfying the following conditions: (1) ${\Phi}$ is nondecreasing and upper semicontinuous in each coordinate variable, and (2) for each t>0, $\psi$(t)=max{$\psi$(t, 0, 0, t, t), ${\Phi}$(t, t, t, 2t, 0), ${\Phi}$(0, t, 0, 0, t)} $\psi$: R$\^$+/ \longrightarrow R$\^$+/ is a nondecreasing upper semicontinuous function from the right. Before sating and proving our main theorems, we give the following lemmas:

• Investigative Magnetic Resonance Imaging
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• v.5 no.1
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• pp.18-23
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• 2001

Purpose : To describe the MRI findings in the bronchial anthracofibrosis mimicking lung cancer on CT examination. Materials and methods : Ten patients, who showed CT findings mimicking lung cancer, were selected among fifty patients of bronchial anthracofibrosis proven by bronchoscopic biopsy, consisting of two men and eight women, ranging in age from 58 to 79 years old faverage age, 68 years old). CT scan and MRI were performed in all patients (n=10). Percutaneous lung biopsy on mass was performed in one patient. MRI findings were analyzed with the emphasis on the signal intensity of the mass (n=4), collapsed lung (n=4) and Iymph node (n=10) on axial T1 and T2-weighted images by two radiologists in consensus. No contrast enhancement was used in all cases. Results : CT scan revealed mass (n=4), atelectasis with obstructive pneumonia(n=4) and bronchial wall thickening(n=2). All patients showed enlarged medistinal Iymph nodes(n=10). The mass showed low signal intensity on T1WI and T2WI (n =4). The collapsed lung in patients with atelectasis indicated intermediate signal intensity on T1WI and low signal intensity on T2WI (n= 4). Nine patients showed low sisnal intensity of Iymph node on T1WI and T2WI, except one patient who showed central high signal intensity with peripheral rim of low signal intensity in right lower paratracheal llmph node on T2WI. Conclusion : Low signal intensity of a mass, collapsed lung, and lymph nodes on T2WI in anthracofibrosis patients may be helpful in differentiation of the lesion from lung cancer.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.1
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• pp.445-452
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• 2015

Transcranial direct current stimulation (tDCS) is a neuromodulatory technique that delivers a low-intensity direct current to the cortical areas, thereby facilitating or inhibiting spontaneous neuronal activity. This study was designed to examine the changes in various sensory functions after tDCS. A single-center, single-blinded, randomized trial was conducted to determine the effect of a single session (August 4 to August 29) of tDCS with the current perception threshold (CPT) in 50 healthy volunteers. Nerve conduction studies (NCS) were performed in relation to the median sensory and motor nerves on the dominant hand to discriminate peripheral nerve lesions. The subjects received anodal tDCS with 1mA for 15 minutes under two different conditions, with 25 subjects in each group. The conditions were as follows: tDCS on the dorsolateral prefrontal cortex (DLPFC) and sham tDCS on DLPFC. The parameters of the CPT was recorded with a Neurometer$^{(R)}$ at frequencies of 2000, 250 and 5 Hz in the dominant index finger to assess the tactile sense, fast pain and slow pain, respectively. In the test to measure the CPT values of the DLPFC in the anodal tDCS group, the values increased significantly in all of 250 and 5 Hz. All CPT values decreased for the sham tDCS. These results showed that DLPFC anodal tDCS can modulate the sensory perception and pain thresholds in healthy adult volunteers. This study suggests that tDCS may be a useful strategy for treating central neurogenic pain in rehabilitation medicine.

• Journal of Animal Science and Technology
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• v.47 no.5
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• pp.759-768
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• 2005

The study was designed to estimate the in vitro rumen by-pass rate of both chromium methionine chelate as an organic supplement and $ClCl_3$ as an inorganic supplement. Rumen by-pass rates of the supplements were evaluted by comparing ruminal metabolites in rumen fluid and Cr and methionine contents in the body of ruminal microorganism. For in vitro digestion examination, basic nutrients for ruminal microbes were supplied with 7g(DM) of feed, 2g of rice straw, and 2g of corn silage per each incubation jar. Three treatments including Control(no supplementation of Cr), T1(1000ppb supplementation of $ClCl_3$) and T2(chromium methionine chelate supplementation equivalent to 1000ppb of Cr content) were prepared with five replications per each treatment. pH of T2 was lower than that of Control and T1 regardless of incubation time. Ammonia content was higher in T2 than in Control and T1 during first 6 hours of incubation. However, the ammonia content in Control was remained low after 6 hours. Total volatile fatty acids(VFA) content in control was increased constantly as incubation time was extended. Therefore, VFA content in T1 and T2 were significantly lower (P<0.05) than those of Control. Dry matter recovery rate by ruminal microorganism was the lowest in T1, however ruminal microbial population was increased most efficiently in T2 during 12 hours of in vitro incubation. Cr concentrations in the body of ruminal microbes were not different(P>0.05) between Control and T2, but it was significantly high in T1(P<0.05). Contents of methionine and cystine in ruminal microbes also were not different between Control and T2(P>0.05), but it was relatively low in T1. Based on the above results, the chromium methionine chelate was believed to by-pass rumen and could remain intact until it reaches small intestine compared to inorganic chromium. This results implies that chromium methionine chelate could be more effective to function in the small intestine of ruminant animals.