• Journal of Korean Society of Spine Surgery
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• v.25 no.4
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• pp.154-159
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• 2018

Study Design: Retrospective radiographic study. Objective: To evaluate the characteristics of concurrent degenerative cervical and lumbar spondylolisthesis. Summary of Literature Review: Concurrent degenerative cervical and lumbar spondylotic diseases have been reported. Given that severe spondylosis can result in spondylolisthesis, one might expect that concurrent spondylolisthesis of the cervical and lumbar spines might also be prevalent. However, the incidence of spondylolistheses in the lumbar and cervical spines might differ due to anatomical differences between the 2 areas. Nonetheless, there is minimal information in the literature concerning the incidence of concurrent cervical and lumbar spondylolisthesis. Material and Methods: We evaluated standing cervical and lumbar lateral radiographs of 2510 patients with spondylosis. Concurrence, age group, gender, and direction of spondylolisthesis were evaluated. Lumbar spondylolisthesis was defined as at least Meyerding grade I and degenerative cervical spondylolisthesis was defined as over 2 mm of displacement on standing lateral radiographs. Results: Lumbar spondylolisthesis was found in 125 patients (5.0%) and cervical spondylolisthesis was found in 193 patients (7.7%). Seventeen patients had both degenerative cervical and lumbar spondylolistheses (0.7%). Lumbar spondylolisthesis is a risk factor for coexisting cervical spondylolisthesis. Lumbar spondylolisthesis was more common in females than males, independent of advancing age. In contrast, degenerative cervical spondylolisthesis was more common in older patients, independent of gender. Anterolisthesis was more common in the lumbar spine. Retrolisthesis was more common in the cervical spine. Conclusions: There was a higher prevalence of degenerative cervical spondylolisthesis in patients with degenerative lumbar spondylolisthesis.

• Journal of Korean Ophthalmic Optics Society
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• v.7 no.2
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• pp.209-215
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• 2002

This study investigated the crystal growth, crystalline structure and the basic optical properties of $SnSe/BaF_2$ epilayers. The SnSe epilayer was grown on $BaF_2$(111) insulating substrates using a hot wall epitaxy(HWE) technique. It was found from the analysis of X-ray diffraction patterns that $SnSe/BaF_2$ epilayer was growing to single crystal with orthorhombic structure oriented [111] along the growth direction. Using Rutherford back scattering(RBS), the atomic ratios of the SnSe was found to be stoichiometric, almost 50 : 50. The best values for the full width at half maximum (FWHM) of the DCXRD was 163 arcsec for SnSe epilarer. The epilayer-thickness dependence of the FWHM of the DCXRD shows that the quality of the $SnSe/BaF_2$ is as expected. The dielectric function ${\varepsilon}$(E) of a semiconductor is closely related to its electronic energy band structure and such relation can be drawn from features around the critical points in the optical spectra. The real and imaginary parts(${\varepsilon}_1$ and ${\varepsilon}_2$) of the dielectric function ${\varepsilon}$ of SnSe were measured. These data are analyzed using a theoretical model known as the model dielectric function(MDF). The optical constants related to dielectric function such as the complex refractive index(n*-n+ik), absorption coefficient (${\alpha}$) and normal- incidence reflectivity (R) are also presented for $SnSe/BaF_2$.

• Journal of the Korean Society of Propulsion Engineers
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• v.2 no.2
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• pp.64-73
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• 1998

In twin spool aero-engine, there may be a S shaped annular duct between high pressure and low pressure spools. The flow passing this S shaped duct experiences the flow acceleration and deceleration due to the convex and concave surface of the duct as well as the increase of blockage according to the boundary layer growth along the surfaces. So, the high pressure compressor which is located behind the S shaped duct is influenced by the non-uniform flow field generated by the geometry of inlet duct. To study the influence of the S shaped duct on the centrifugal stage, performance tests were implemented for the compressor with straight cylindrical inlet duct and with S shaped inlet duct, respectively. The test results showed that the performance, such as pressure ratio and efficiency, of the compressor with S shaped duct was worse than that of the compressor with cylindrical duct. And the compressor with S shaped duct had reduced maximum flow rate around design speed. To investigate the cause of performance degradation, flow anlaysis was performed for the impeller in front of which is located S shaped annular duct. The result of CFD showed the strong acceleration of the flow in the axial direction around the inducer tip region which caused the increase of relative mach number and the decrease of incidence angle of the flow.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.31 no.6_1
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• pp.447-454
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• 2013

The geolocation accuracy of SAR satellite imagery is affected by orbit and sensor information and external variables such as DEM accuracy and atmospheric delay. To predict geolocation accuracy of KOMPSAT-5 and KOMPSAT-6, this paper uses TerraSAR-X imagery which has similar spec. Simulation data for sensitivity analysis are generated using range equation and doppler equation with several key error sources. As a result of simulation analysis, the effect of sensor information error is larger than orbit information error. Especially, onboard electronic delay needs to be monitored periodically because this error affects geolocation accuracy of slant range direction by 30m. Additionally, DEM accuracy causes geolocation error by 20~30m in mountainous area and atmospheric delay can occur by 5m in response to atmospheric condition and incidence angle.

• The Journal of the Korean life insurance medical association
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• v.2 no.1
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• pp.152-181
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• 1985

A statistical analysis on the cardiothoracic ratio in insurance medicine was carried out for 5,200 insured persons who were medically examined including photofluorography of the chest at the Honam medical department, Dong Bang life insurance Company, Ltd from November, 1979 to August, 1984. The results were as follows: 1. The mean value of the cardiothoracic ratio in all of the insured was $44.2{\pm}4.3%$. The mean value of the cardiothoracic ratio was $43.1{\pm}4.1%$ in all males and $45.2{\pm}4.2%$ in all females, and the difference of the values between males and females showed statistical significance(P<0.001). In each age group, the mean value of the cardiothoracic ratios of female was higher than that of male without exception and the difference of the values between males and females showed statistical significance(P<0.001). The mean value of the cardiothoracic ratio showed gradual increase with age from the second to sixth decade in male(P<0.05 or 0.001 after fourth decade) and from the second to seventh decade in female(P<0.05 or 0.001 from the second to sixth decade). 2. Correlation between both sexes and among age groups relating to the cardiothoracic ratios of the insureds seen to be a physiological phenomenon of the cardiac size and should be considered on the rating of the cardiothoracic ratio. Based on the correlation above mentioned and an author's assumption that the incidence of normal and abnormal cardiothoracic ratios in each age group would show the same rate in male and female, author prepared a modified rating table from the existing table; in male group the existing rating table is used and in female group the ratings of 0, 30-50, 50-100 and 100-D are to calculate by the cardiothoracic ratio of 51%or under, 52-56%, 57-61% and 62% or over respectively in the age group below 39, by the cardiothoracic ratio of 52% or under, 53-57%, 58%-62% and 63% or over respectively in the age group of 40-49, by the cardiothoracic ratio of 53% or under, 54-58%, 59-63% and 64% or over respectively in the age group over 60. 3. The relative frequency distribution polygons of the cardiothoracic ratio of both sexes drawn in a pair on one coordinate plane revealed lying in juxtaposition each other horizontally and showed the shifting of females polygon to male's one toward the direction of greater value of the cardiothoracic ratio at a short distance which increased gradually with age. 4. The minimum cardiothoracic ratio was 31.2% and the maximum cardiothoracic ratio was 63.6% in all of the insured. 5. In each age group, no significant sex difference was found in the relative frequency distribution of ratings by the cardiothoracic ratios of 5,200 insureds by using the rating table modified by author, while significant sex difference was found by using the existing rating table.

• Journal of Korean Ophthalmic Optics Society
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• v.9 no.1
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• pp.35-41
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• 2004

This study investigated the crystal growth, crystalline structure and the basic optical properties of $PbSnSe/BaF_2$ epilayers. The PbSnSe epilayer was grown on $BaF_2$(111) insulating substrates using a hot wall epitaxy (HWE) technique. It was found from the analysis of X-ray diffraction patterns that $PbSnSe/BaF_2$ epilayer was grown single crystal with a rock-salt structure oriented along [111] the growth direction. Using Rutherford back scattering, the atomic ratios of the PbSnSe was found to be proper stoichiometric. The best values for the full width at half maximum (FWHM) of the DCXRD was 162 arcsec for PbSnSe epilayer. The epilayer-thickness dependence of the FWHM of the DCXRD shows that the quality of the $PbSnSe/BaF_2$ is as expected. The dielectric function ${\varepsilon}(E)$ of a semiconductor is closely related to its electronic energy band structure and such relation can be drawn from features around the critical points(CPs) in the optical spectra. The real and imaginary parts(${\varepsilon}1$ and ${\varepsilon}2$) of the dielectric function ${\varepsilon}$ of PbSe were measured, and the observed spectra reveal distinct structures at energies of the E1, E2 and E3 CPs. These data are analyzed using a theoretical model known as the model dielectric function (MDF). The optical constants related to dielectric function such as the complex refractive index ($n^*=n+ik$), absorption coefficient (${\alpha}$) and normal-incidence reflectivity (R) are also presented for $PbSnSe/BaF_2$.

• Korean Journal of Adult Nursing
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• v.15 no.3
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• pp.472-482
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• 2003

Purpose: Purposes of this study were to understand the current trends on complementary therapy in relieving chemotherapy-induced nausea and vomiting and to suggest the future research direction. Method: Subjects were selected on CINAHL, MEDLINE, Korean Academy Data Base from 1980 to 2001 which used nausea, vomiting, chemotherapy and complementary therapy as key words in experimental studies. Eight korean articles and twenty-one international articles were analyzed in terms of general characteristics, research methods, and types of complementary therapy. Data were analyzed by using descriptive statistical methods. Result: Since 2000, researchers have more actively used complementary therapy. In subject characteristics, mean age was 35.5 years old, 45% of the researchers were performed with high level of incidence of chemotherapy induced vomiting, 14% of them set limit of consecutive cycle during research, and 65% of them did not comment the selecting criteria of sample. About 60% of them were designed post-test only control group; 35% used INV by Rhodes, 31% used Likert scale, and 24% used VAS for dependent variable. Muscle relaxation therapy was mostly applied for relief of nausea and vomiting. Conclusion: Further studies will be needed to control extrinsic variables affecting nausea and vomiting in research design and to accumulate evidence with studies applying various complementary therapies.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.12
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• pp.5107-5110
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• 2014

Background: The incidence rate of thyroid cancer has been increasing worldwide in recent years, and it is also the most prevalent cancer when it comes to the number of patients among Korean women. With it, ultrasonographic screening test has also become very common. However, there is still controversy over the performance of this screening test. Therefore, the National Evidence-based Healthcare Collaborating Agency (NECA) organized a Round-table Conference on the issues regarding ultrasonographic screening for thyroid cancer in Korea. The objective of the conference was mainly about delivering worthwhile information reflecting social value for the current situation, which was based on evidence surrounding thyroid cancer screening that relevant experts investigated and agreed on. The significance of this Round-table Conference lies in the fact that we reviewed the current evidence, and we were able to discuss the social value and future direction for ultrasonographic screening in Korea.

• Journal of Korean Neurosurgical Society
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• v.29 no.9
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• pp.1188-1194
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• 2000

Objective : Internal carotid-posterior communicating artery(IC-PC) aneurysms can be clipped easily without any special preparations. Occasionally, however, it is difficult to clip the low-lying IC-PC aneurysms without some kinds of additional procedures. Clinical Material and Methods : We experienced four cases of low-lying IC-PC aneurysms, which the intradural anterior clinoidectomy and/or anterior petroclinoid fold(APF) resection was essential to expose the proximal side of the aneurysmal neck and/or proximal control. One patient harbored two low-lying IC-PC aneurysms bilaterally. The patients were divided into two groups according to the necessity of anterior clinoidectomy : Group I(n=4) that needed an intradural clinoidectomy and/or APF resection and Group II(n=29) that had IC-PC aneurysms, easily clipped without any special preparation. Also, various radiometric parameters were measured through the preoperative angiograms. Results : The incidence of such aneurysms was 12% among a total of thirty-three surgically treated IC-PC aneurysms during lasr 3 years. Among four cases, three cases presented with subarachnoid hemorrhage and all aneurysmal sac projected to postero-inferior direction. In our study, We initially considered the necessity of intraoperative anterior clinoid process(ACP) removal and/or resection of APF in cases of shorter distance less than 5.6mm between the proximal aneurysmal sac and tip of the ACP(p<0.001), and the proximal portion of aneurysmal neck has located below the interclinoid line(p=0.001). Conclusion : Through a careful preoperative evaluation, some radiometric parameters can be used to determine whether the ACP should be removed in clipping of the low-lying IC-PC aneurysms. Unlike to total removal of the ACP, the intradural partial anterior clinolidectomy and/or APF resection, which are more familiar to surgeons, reduce the risks of the premature rupture, operative time, and also contribute a more precise clip placement with proximal control than the extradural clinoidectomy.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.17 no.3
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• pp.129-136
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• 2017

Geographic Information System The geographic information system (GIS) has been limited to the government and some public sectors. Recently, the market has been diversified by combining with other areas such as mobile and CRM (Customer Relationship Management). The development direction of GIS technology in the 21st century is Web GIS, 3D GIS, mobile GIS, LBS, etc. as general technology for GIS application system development and spatial information service. In this study, we developed a new concept marking nail (a marking nail with built - in intelligent storage memory device) from the function of simple positioning of a marking nail related to a previously used underground item,, Burial depth, pipe thickness, piping material, management agency, contractor, contact, etc.) and store it in DB server, if necessary.Make it available in the right place. Through this research, it is possible to prevent and minimize various accidents caused by irregular excavation works, etc., and to provide information for establishing countermeasures related to sink holes. In order to provide systematic and reliable information on underground burial management, it was proposed to input information conveniently in the field, and the purpose was to reduce the incidence of buried underground pipes absolutely.