• Journal of Acupuncture Research
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• v.17 no.3
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• pp.116-124
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• 2000

This clinical study was carried out 15 cases with lumbar spinal stenosis patients, who had been admitted and diagnosed by Computed Tomography from June, 1999 to May, 2000, in the department of acupuncture and moxibustion. Hanseo University Oriental Medical Nospital. The results obtained from this study were as follows; 1. We investigated 10 female and 5 male patients. The age distribution was from early 20's to 70's, among which 30's and 50's were most common. 2. The most common duration of symptom was less than a year(46.7%). 3. Regarding to the number of the involved levels, one was 12 cases(80%), two was 3 cases(20.0%). In the one level cases, L4~5 was the most common involved site. 4. Regarding to the clinical symptoms, low back pain was the most common, followed by lower extremity radiating pain, intermittent claudication, lower extremity paresthesia. 5. In orthopaedic examinations, positive sign in Milgram test was 80.0%, positive sign in straight leg raising test was 40.0%, and positive sign in Braggard test was 33.3%. Inneurologic examinations, sensory loss was seen in 60.0%, motor weakness and decreased deep tendon reflex were 26.7% in each. 6. According to clinical symptom scale proposed by Chae(1989), grade I1I was the most common (53.3%), followed by grade II, grade IV, grade I . 7. According to treatment outcome scale proposed by Chae(1989), Good was the most common (73.3%), followed by Excelleat, Fair and Poor.

• Korean Journal of Radiology
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• v.25 no.2
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• pp.166-178
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• 2024

Objective: This study aimed to determine the predictive performance of non-contrast CT (NCCT) signs for hemorrhagic growth after intracerebral hemorrhage (ICH) when stratified by onset-to-imaging time (OIT). Materials and Methods: 1488 supratentorial ICH within 6 h of onset were consecutively recruited from six centers between January 2018 and August 2022. NCCT signs were classified according to density (hypodensities, swirl sign, black hole sign, blend sign, fluid level, and heterogeneous density) and shape (island sign, satellite sign, and irregular shape) features. Multivariable logistic regression was used to evaluate the association between NCCT signs and three types of hemorrhagic growth: hematoma expansion (HE), intraventricular hemorrhage growth (IVHG), and revised HE (RHE). The performance of the NCCT signs was evaluated using the positive predictive value (PPV) stratified by OIT. Results: Multivariable analysis showed that hypodensities were an independent predictor of HE (adjusted odds ratio [95% confidence interval] of 7.99 [4.87-13.40]), IVHG (3.64 [2.15-6.24]), and RHE (7.90 [4.93-12.90]). Similarly, OIT (for a 1-h increase) was an independent inverse predictor of HE (0.59 [0.52-0.66]), IVHG (0.72 [0.64-0.81]), and RHE (0.61 [0.54-0.67]). Blend and island signs were independently associated with HE and RHE (10.60 [7.36-15.30] and 10.10 [7.10-14.60], respectively, for the blend sign and 2.75 [1.64-4.67] and 2.62 [1.60-4.30], respectively, for the island sign). Hypodensities demonstrated low PPVs of 0.41 (110/269) or lower for IVHG when stratified by OIT. When OIT was ≤ 2 h, the PPVs of hypodensities, blend sign, and island sign for RHE were 0.80 (215/269), 0.90 (142/157), and 0.83 (103/124), respectively. Conclusion: Hypodensities, blend sign, and island sign were the best NCCT predictors of RHE when OIT was ≤ 2 h. NCCT signs may assist in earlier recognition of the risk of hemorrhagic growth and guide early intervention to prevent neurological deterioration resulting from hemorrhagic growth.

• Journal of the Korean Mathematical Society
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• v.58 no.5
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• pp.1181-1209
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• 2021

In the present paper, we are concerned with the existence of ground state sign-changing solutions for the following Schrödinger-Poisson-Kirchhoff system $$\;\{\begin{array}{lll}-(1+b{\normalsize\displaystyle\smashmargin{2}{\int\nolimits_{{\mathbb{R}}^3}}}{\mid}{\nabla}u{\mid}^2dx){\Delta}u+V(x)u+k(x){\phi}u={\lambda}f(x)u+{\mid}u{\mid}^4u,&&\text{in }{\mathbb{R}}^3,\\-{\Delta}{\phi}=k(x)u^2,&&\text{in }{\mathbb{R}}^3,\end{array}$$ where b > 0, V (x), k(x) and f(x) are positive continuous smooth functions; 0 < λ < λ₁ and λ₁ is the first eigenvalue of the problem -∆u + V(x)u = λf(x)u in H. With the help of the constraint variational method, we obtain that the Schrödinger-Poisson-Kirchhoff type system possesses at least one ground state sign-changing solution for all b > 0 and 0 < λ < λ₁. Moreover, we prove that its energy is strictly larger than twice that of the ground state solutions of Nehari type.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.41 no.2
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• pp.167-173
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• 2018

Each municipality is promoting signboard improvement projects, but the effectiveness is not great. The main reason for this is that when the signboard is manufactured the location of the shop is only dependent on the visual aspiration effect and it is not harmonized with the building by applying uniform design. The signboard are installed almost everywhere in the city, such as residential, natural and commercial environments. And the signboard provides various services such as traffic information and life safety to customers. Also, by applying design and functional elements, we can enhance the competitiveness of companies and improve the urban environment by enhancing the mutual connection effect of customers and space. The purpose of this study is to investigate the effect of design elements and functional elements of the signboard on customer preference. In other words, we conducted surveys and analyzes of 152 specialists and non-experts (customers, self-employed). As a result of the study, the following conclusions were drawn. First, the functions and design elements of signboards are important factors that have a positive effect on customer preference. Second, the function of the signboard has a positive(+) influence on the customer preference, and the information providing function and the corporate image side function directly affect the customer preference. Third, color elements have a positive(+) meaningful effect on customer preference. Especially, similar color sign affects customer preference positively. Fourth, the signboard design component has a positive(+) significant effect on customer preference. In particular, typefaces have a positive effect on customer preference.

• Journal of the Chungcheong Mathematical Society
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• v.33 no.4
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• pp.445-468
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• 2020

A long-time behavior of global solutions for a dispersive-dissipative equation with time-dependent damping terms is investigated under null Dirichlet boundary condition. By virtue of an appropriate new Lyapunov function and the Lojasiewicz-Simon inequality, we show that any global bounded solution converges to a steady state and get the rate of convergence as well, when damping coefficients are integrally positive and positive-negative, respectively. Moreover, under the assumptions on on-off or sign-changing damping, we derive an asymptotic stability of solutions.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.304-305
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• 2013

We report a positive exchange bias (HE) in thinmultilayered filmscontaining nano-oxide layer. The positive HE, obtained for our system results from an antiferromagnetic coupling between the ferromagnetic (FM) CoFe and the antiferromagnetic (AFM) CoO layers, which spontaneously form on top of the nano-oxide layer (NOL). The shift in the hysteresis loop along the direction of thecooling field and the change in the sign of exchange bias are evidence of antiferromagnetic interfacial exchange coupling between the CoO and CoFe layers. Our calculation indicates that uncompensated oxygen moments in the NOL results in antiferromagnetic interfacial exchange coupling between the CoO and CoFe layers. One of the interesting features observed with our system is that it displays the positive HE even above the bulk Neel temperature (TN) of CoO. Although the positive HEsystem has a different AFM/FM interfacial spin structure compare to that of the negative HE one, the results of the angular dependence measurements show that the magnetization reversal mechanism can be considered within the framework of the coherent rotation model.

• Journal of Korean Neurosurgical Society
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• v.54 no.4
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• pp.302-308
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• 2013

Objective : MR perfusion and single photon emission computerized tomography (SPECT) are well known imaging studies to evaluate hemodynamic change between prior to and following superficial temporal artery (STA)-middle cerebral artery (MCA) anastomosis in moyamoya disease. But their side effects and invasiveness make discomfort to patients. We evaluated the ivy sign on MR fluid attenuated inversion recovery (FLAIR) images in adult patients with moyamoya disease and compared it with result of SPECT and MR perfusion images. Methods : We enrolled twelve patients (thirteen cases) who were diagnosed with moyamoya disease and underwent STA-MCA anastomosis at our medical institution during a period ranging from September of 2010 to December of 2012. The presence of the ivy sign on MR FLAIR images was classified as Negative (0), Minimal (1), and Positive (2). Regions were classified into four territories: the anterior cerebral artery (ACA), the anterior MCA, the posterior MCA and the posterior cerebral artery. Results : Ivy signs on preoperative and postoperative MR FLAIR were improved (8 and 4 in the ACA regions, 13 and 4 in the anterior MCA regions and 19 and 9 in the posterior MCA regions). Like this result, the cerebrovascular reserve (CVR) on SPECT was significantly increased in the sum of CVR in same regions after STA-MCA anastomosis. Conclusion : After STA-MCA anastomosis, ivy signs were decreased in the cerebral hemisphere. As compared with conventional diagnostic modalities such as SPECT and MR perfusion images, the ivy sign on MR FLAIR is considered as a useful indicator in detecting brain hemodynamic changes between preoperatively and postoperatively in adult moyamoya patients.

• Journal of Korea Port Economic Association
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• v.31 no.1
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• pp.1-14
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• 2015

The standard GARCH model imposing symmetry on the conditional variance, tends to fail in capturing some important features of the data. This paper, hence, introduces the models capturing asymmetric effect. They are the EGARCH model and the GJR model. We provide the systematic comparison of volatility models focusing on the asymmetric effect of news on volatility. Specifically, three diagnostic tests are provided: the sign bias test, the negative size bias test, and the positive size bias test. This paper shows that there is significant evidence of GARCH-type process in the data, as shown by the test for the Ljung-Box Q statistic on the squared residual data. The estimated unconditional density function for squared residual is clearly skewed to the left and markedly leptokurtic when compared with the standard normal distribution. The observation of volatility clustering is also clearly reinforced by the plot of the squared value of residuals of export volume and values. The unconditional variance of both export volumes and export value indicates that large shocks of either sign tend to be followed by large shocks, and small shocks of either sign tend to follow small shocks. The estimated export volume news impact curve for the GARCH also suggests that $h_t$ is overestimated for large negative and positive shocks. The conditional variance equation of the GARCH model for export volumes contains two parameters ${\alpha}$ and ${\beta}$ that are insignificant, indicating that the GARCH model is a poor characterization of the conditional variance of export volumes. The conditional variance equation of the EGARCH model for export value, however, shows a positive sign of parameter ${\delta}$, which is contrary to our expectation, while the GJR model exhibits that parameters ${\alpha}$ and ${\beta}$ are insignificant, and ${\delta}$ is marginally significant. That indicates that the asymmetric volatility models are poor characterization of the conditional variance of export value. It is concluded that the asymmetric EGARCH and GJR model are appropriate in explaining the volatility of export volume, while the symmetric standard GARCH model is good for capturing the volatility.

• Clinical and Experimental Reproductive Medicine
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• v.25 no.2
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• pp.153-160
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• 1998

The objective of this retrospective study was to evaluate whether the transvaginal ultrasonographic analysis of endometrial pattern and thickness could predict the stage of menstrual cycle. Endometrial pattern and thickness were observed in those patients receiving infertility work up from April, 1994 to July, 1998 at Seoul National University Hospital. The study group was 185 patients with normal regular menstrual cycles. Among them, 44 patients received endometrial biopsy, and the date of endometrium was compared with the observed endometrial pattern and thickness. The observed endometrial pattern was presence or absence of central cavity echogenicity, triple line sign, endometrial hypoechogenicity, ring sign, endometrial hyperechogenicity and posterior acoustic sonic enhancement. The results were as follows; Central cavity echogenicity was seen throughout menstrual cycle. Triple line sign was observed in 81.1% of patients during early secretory phase. However, in mid to late secretory phase, triple line sign was appeared in only 6.8%. The percentage of positive endometrial hypoechogenicity was highest in early secretory phase. In contrast to hypoechogenicity, positive endometrial hyperechogenicty was highest in mid to late secretory phase. Ring sign was observed in 73.5% of the patients during early secretory phase with peak incidence. Posterior acoustic enhancement was seen in 72.7% of the patients during late secretory phase. The sensitivity and specificity of being a secretory phase if the patients showed hyperechogenic endometrium, were 84.2%, 83.3% respectively. The sensitivity and specificity of being a secretory phase if the patients showed posterior acoustic enhancement were 93.8%, 58.3% respectively. Endometrial thickness was not correlated with endometrial dating. In conclusion, transvaginal ultrasonographical delineation of the endometrial pattern might be useful tool in predicting endometrial status during normal menstrual cycle. But, endometrial thickness could not predict the endometrial dating.

• Health Policy and Management
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• v.27 no.4
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• pp.304-314
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• 2017

Background: This study aimed to analyze effects of postpartum care services to women after birth, identify the factors affecting their use, and examine the extent of income-related inequality in the postpartum care services utilization and expenditures using Korean Health Panel data between 2010 and 2013. Methods: The panel data of the year 2010-2013 of the 247 women after birth were used. First, EuroQoL-5D was used to evaluate the effects of postpartum care service to women's quality of life. Second, multinominal logistic regression analysis was used to identify determinants of the use of the postpartum care services. Finally, concentration index and HIwv (horizontal equity) index were used to find that the concentration index for the inequality in the use of postpartum care services showed negative sign, which implied pro-rich. Results: The estimation results showed that utilization of the postpartum services has a positive effect on women after birth. Also age, area of residence, and number of household members turn out to be the factors of using postpartum services. And there are inequality in the use of postpartum care services whose HIwv index showed positive sign, which implied pro-rich. Conclusion: Therefore, the government's policy of the postpartum care service is necessary to be expanded and diversified considering the personal characteristics and equity of the women after birth.