• Journal of Korean Society of Industrial and Systems Engineering
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• v.33 no.3
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• pp.63-70
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• 2010

Based on the known results of the expected busy periods for the triadic Min (N, T, D) and Max (N, T, D) operating policies applied to a controllable M/G/1 queueing model, a relation between them is constructed. Such relation is represented in terms of the expected busy periods for the simple N, T and D, and the dyadic Min (N, T), Min (T, D) and Min (N, D) operating policies. Hence, if any system characteristics for one of the two triadic operating policies are known, unknown corresponding system characteristics for the other triadic operating policy could be obtained easily from the constructed relation.

• Korean Journal of Poultry Science
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• v.29 no.1
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• pp.25-35
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• 2002

Two experiments were conducted to studs the effects of early-life feed restriction, ages and duration on compensatory growth, feed efficiency, and abdominal fat pad deposition in broilers. The chicks were randomly assigned to four treatments (experiment 1) or seven treatments (experiment 2) . Each dietary treatment was replicated with three floor pens in both experiments, and twenty chicks were assigned to each pen. In experiment 1, birds in control group (C) were full-fed throughout the study. For treatments 1, 2, and 3, bards were fed diets containing 0.75 kcal ME/gB $W^{o.67}$/d for 3 d(T1), 1.5 ㎉ ME/gB $W^{o.67}$/d for 5 d (T2), and 2.25 local ME/gB $W^{0.67}$/d for 7 d (T3), all imposed beginning at 7 d of age. The selected value seems appropriate for maintenance feeding because the feed restriction at T1 resulted no growth in virtually. Although the birds previously subjected with restricted feeding significantly (P<0.05) enhanced growth partly (in 22~49 d), the weight gain over the entire growth period (7-49 d) was not influenced by the restricted feeding Programs. Whereas, the restricted feedings had effects with significant (P<0.75) increase in feed intake not only in 22~49 d, but in overall period (7-49 d). The feed conversion for the birds previously subjected with restricted feeding was significantly (P<0.05) improved after 21 d. The birds with restricted feedings (T1,T2,T3) showed better (P<0.05) feed conversion ratio than C both in 22-49 d and in 7-49 d. The restricted feeding programs did not show effects in reducing for abdominal fat pad deposition or mortality In experiment 2, the birds of C were full-fed in overall period. But for treatments 1, 2, 3, 4, 5, and 6 (T1-T6),the birds were fed diets containing 0.75 ㎉ ME/gB $W^{0.67}$/d for 3 or 5 d, starting at either 4, 7 or 10 d of age. The selected value seems appropriate for maintenance feeding because the feed restriction resulted no growth in virtually; which was same as experiment.

• Korean Journal of Radiology
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• v.22 no.5
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• pp.782-791
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• 2021

Objective: To evaluate the signal intensity of the periosteum using ultrashort echo time pulse sequence with three-dimensional cone trajectory (3D UTE) with or without fat suppression (FS) to distinguish from artifacts in porcine tibias. Materials and Methods: The periosteum and overlying soft tissue of three porcine lower legs were partially peeled away from the tibial cortex. Another porcine tibia was prepared as three segments: with an intact periosteum outer and inner layer, with an intact periosteum inner layer, and without periosteum. Axial T1 weighted sequence (T1 WI) and 3D UTE (FS) were performed. Another porcine tibia without periosteum was prepared and subjected to 3D UTE (FS) and T1 WI twice, with positional changes. Two radiologists analyzed images to reach a consensus. Results: The three periosteal tissues that were partially peeled away from the cortex showed a high signal in 3D UTE (FS) and low signal on T1 WI. 3D UTE (FS) showed a high signal around the cortical surface with an intact outer and inner periosteum, and subtle high signals, mainly around the upper cortical surfaces with the inner layer of the periosteum and without periosteum. T1 WI showed no signal around the cortical surfaces, regardless of the periosteum state. The porcine tibia without periosteum showed changes in the high signal area around the cortical surface as the position changed in 3D UTE (FS). No signal was detected around the cortical surface in T1 WI, regardless of the position change. Conclusion: The periosteum showed a high signal in 3D UTE and 3D UTE FS that overlapped with artifacts around the cortical bone.

• Journal of applied mathematics & informatics
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• v.34 no.3_4
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• pp.269-284
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• 2016

In this paper, we firstly use Krasnosel'skii fixed point theorem to investigate positive solutions for the following three-point boundary value problems for p-Laplacian with a parameter $({\phi}_P(D^{\alpha}_{0}+u(t)))^{\prime}+{\lambda}f(t, u(t))=0$, 0$D^{\alpha}_{0}+u(0)=u(0)=u{\prime}{\prime}(0)=0$, $u^{\prime}(1)={\gamma}u^{\prime}(\eta)$ where ϕ_p(s) = |s|^p−2s, p > 1, $D^{\alpha}_{0^+}$ is the Caputo's derivative, α ∈ (2, 3], η, γ ∈ (0, 1), λ > 0 is a parameter. Then we use Leggett-Williams fixed point theorem to study the existence of three positive solutions for the fractional boundary value problem $({\phi}_P(D^{\alpha}_{0}+u(t)))^{\prime}+f(t, u(t))=0$, 0$D^{\alpha}_{0}+u(0)=u(0)=u{\prime}{\prime}(0)=0$, $u^{\prime}(1)={\gamma}u^{\prime}(\eta)$ where ϕ_p(s) = |s|^p−2s, p > 1, $D^{\alpha}_{0^+}$ is the Caputo's derivative, α ∈ (2, 3], η, γ ∈ (0, 1).

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.6 no.1
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• pp.12-22
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• 1994

Time evolution of linear water waves on a constant depth generated by a disturbance is analyzed by asymptotic methods; stationary phase, steepest descents and leading wave approximation. In order to verify the derived formulae of surface displacements for 1-D and 2-D waves. surface displacements are calculated and plotted from both the formulae and a numerical integration. The existing results for surface displacements are verified in which the leading amplitude of 1-D waves during the evolution decays as f- T/B, the rest of the wavetrain as t$^{-1}$ 2/ and the rest of the wavetrain of 2-D waves as t-1. But it is shown that the leading amplitude of 2-D waves decays as t 5/6 which is different from Kajiura's result t$^{-4}$ 3/.

• The Korean Journal of Pharmacology
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• v.27 no.2
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• pp.135-144
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• 1991

Using T-lymphocytes obtained from rat peripheral blood, we found that the 44kD/pI6.8 protein was the major phosphoprotein of T-lymphocytes under basal condition, and that the 44kD/pI6.3 protein was a new phosphoprotein appeared in T-lymphocytes stimulated with ${\beta}-agonist$. The phosphorylation of the 44kD/pI6.3 protein was also induced by forskolin but inhibited by H-8 pretreatment. To clarify the character of the 44kD/pI6.3 protein, we used Con-A and kinase inhibitors, H-7 and W-7. Con-A stimulation induced phosphorylation of 44kD/pI 6.3 protein but that was inhibited by W-7 pretreatment. The phosphorytation of 44kD/pI6.3 protein was not induced by the PKC activator, PMA. Instead, the phosphorylation of 44kD/pI6.8 protein was reduced by H-7, a PKC inhibitor. From the above results,it can be concluded that the 44kD/pI6.3 protein can be a common substrate for A-kinase and CaM kinase. The two dimensional tryptic peptide mapping revealed that the 44kD/pI6.8 and 44kD/pI6.3 proteins are different.

• Investigative Magnetic Resonance Imaging
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• v.19 no.1
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• pp.31-36
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• 2015

Purpose: To compare the depiction of brain metastases on contrast-enhanced images with 7.0 tesla (T) and at 1.5T MRI. Materials and Methods: Four consecutive patients with brain metastases were scanned on 7.0T whole-body scanner and 1.5T MRI. A 3D T1-weighted gradient echo sequence (3D T1-GRE) at 1.5T (voxel size = $0.9{\times}0.9{\times}1.5mm^3$ after double-dose, gadoterate meglumine, Gd-DOTA) was compared to a 7.0T 3D T1-GRE sequence (voxel size = $0.4{\times}0.4{\times}0.8mm^3$, single-dose Gd-DOTA) in four patients after a 5 minute delay. The number of contrast-enhancing metastases in MPRAGE images was compared in each patient by two radiologists in consensus. We measured contrast ratio of enhancing brain metastases and white matter in 1.5T and 7.0T. Results: In all four patients 7.0T 3D T1-GRE images after single-dose Gd-DOTA and 1.5T after double-dose Gd-DOTA depicted 11 brain metastases equally. In the quantitative analysis of contrast ratios of enhancing brain metastases and white matter, the 1.5T 3D T1-GRE after double-dose showed an increased contrast ratio compared to 7.0T 3D T1-GRE after single-dose ($0.961{\pm}0.571$ versus $0.885{\pm}0.494$; n = 11 metastases). But this difference was not statistically significant (P = 0.711). Conclusion: Our preliminary results indicate that 7.0T single-dose Gd-enhanced images were not different to 1.5T double-dose Gd-enhanced images for the detection of brain metastases.

• Investigative Magnetic Resonance Imaging
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• v.13 no.2
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• pp.183-189
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• 2009

Purpose : To evaluate the usefulness of three-dimensional (3D) maximal intensity projection (MIP) reconstruction method in breast MRI. Materials and Methods : Total 54 breasts of consecutive 27 patients were examined by breast MRI. Breast MRI was performed using GE Signa Excite Twin speed (GE medical system, Wisconsin, USA) 1.5T. We obtained routine breast MR images including axial T2WI, T1WI, sagittal T1FS, dynamic contrast-enhanced T1FS, and subtraction images. 3D MIP reconstruction images were obtained as follows; subtraction images were obtained using TIPS and early stage of contrast-enhanced TIPS images. And then 3D MIP images were obtained using the subtraction images through advantage workstation (GE Medical system). We detected and analyzed the lesions in the 3D MIP and routine MRI images according to ACR $BIRADS^{(R)}$ MRI lexicon. And then we compared the findings of 3D MIP and those of routine breast MR images and evaluated whether 3D MIP had additional information comparing to routine MR images. Results : 3D MIP images detect the 43 of 56 masses found on routine MR images (76.8%). In non-mass like enhancement, 3D MIP detected 17 of 20 lesions (85 %). And there were one hundred sixty nine foci at 3D MIP images and one hundred nine foci at routine MR images. 3D MIP images detected 14 of 23 category 3 lesions (60.9%), 11 of 16 category 4 lesions (68.87%), 28 of 28 Category 5 lesions (100%). In analyzing the enhancing lesions at 3D MIP images, assessment categories of the lesions were correlated as the results at routine MR images (p-value < 0.0001). 3D MIP detected additional two daughter nodules that were descriped foci at routine MR images and additional one nodule that was not detected at routine MR images. Conclusion : 3D MIP image has some limitations but is useful as additional image of routine breast MR Images.

• Environmental Analysis Health and Toxicology
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• v.15 no.3
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• pp.107-113
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• 2000

Chlorophenoxy acids are one of the most useful classes of chlorinated herbicides. Specially 2, 4-D and 2, 4, 5-T were known to endocrine distruptors. In this study, these pesticides in water samples were extracted by liquid-liquid extration at acidic conditions and then derivatization of acidic group was carried out various esterifications using by CH$_3$I/Acetone -K$_2$CO$_3$, H$_2$SO$_4$/MeOH or TFAA/TFE. That result, Sensitivities of TFE derivatized 2, 4-D and 2, 4, 5-T are prior to the others. The recoveries of 2, 4-D and 2, 4, 5-T were 98% and 82% respectively using diethyl ether as an extracting solvent.

• International Journal of Internet, Broadcasting and Communication
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• v.6 no.2
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• pp.13-16
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• 2014

This study aims to examine the effects of watching 2D and 3D images on the blink rate. Regarding the image watch, their blink rate for 2D and 3D images was separately checked for 1 minute in the 1m distance, before the watch, after 15 minutes of watch, and after 30 minutes of watch. About the change of their blink rate in the 2D image watch, it tended to become higher than that before watching the image; however, there was no statistical significance (paired t-test, p=0.106, p=0.062). And in the 2D image watch, it tended to increase in comparison between after 15 minutes and after 30 minutes, but there was no statistical significance (paired t-test, p=0.623). Meanwhile, about the change of their blink rate in the 3D image watch, it tended to decrease statistically significantly both after 15 minutes and after 30 minutes when compared with that before watching the image (paired t-test, p=0.000, p=0.000). In the 3D image watch, it tended to increase in comparison between after 15 minutes and after 30 minutes; however, there was no statistical significance (paired t-test, p=0.867).