• Proceedings of the KSRS Conference
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• 2007.10a
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• pp.382-385
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• 2007

Constantly enhancing positioning accuracy by the Global Positioning System (GPS) technique is of great importance, but challenging, especially after the GPS positioning technique has been improved considerably during the past two decades. The associated main error sources have been reduced substantially, if not eliminated. Troposhpeic influence with its highly temporal and spatial variability appears to be one of the major error sources. It is hence an increased interest among GPS researchers to reduce the tropospheric influence or delay. Two techniques have been commonly implemented to correct the tropospheric impact. The first technique, known as parameter estimation, characterizes the path delay with empirical models and the parameters of interest are determined from the GPS measurements. The second strategy, termed as external correction, involves independent path delay measurements. The present study is an integration of both techniques in which the parameter estimation as well as external correction are used to correct the path delay for $110{\sim}210$ km range baselines. Twenty-four parameters have been obtained in 24 hours solution by setting the cutoff angle at 3 and 15 degrees for parameter estimation strategy. Measurements from meteorological instruments and water vapor radiometer (WVR) are applied in the GPS data processing, separately, as an external strategy of present research work. Interesting results have been found, indicating more stable repeatability in baseline when the external correction strategy is applied especially with the inclusion of WVR observations. The offset of an order of 1 cm is found in the baselines determined by the two strategies. On the other hand, parameter estimation exhibits more stable in terms of GPS height repeatability. The offset in the GPS height determined by the two strategies is on the order of few centimeters.

• 보존과학연구
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• s.27
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• pp.165-180
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• 2006

The research was conducted to understand type of iron used by those who lived at dwelling site of Yangsoo-ri in between the first century B.C. and the first century A.D. to make steel products and their technique such as steel making process and heat treatment, based on micro structure information obtained through microscopic metallographic structure analysis with SEM-EDS of six steel productsexhumed at the site. Key findings are summarized as below. In the sense that Si-Ca-Al style and less than 0.5% of Ti were found in the non-metallic inclusion, the material used for forged iron ware was magnetite resolved in that. It is, however, unclear whether magnetite was resolved at high temperature or at low temperature. Microscopic structure analysis revealed that forged steel products were made through repeated hot working, the technique of molding by hitting after heating in the process of resolving and molding iron. As a result, the iron used here for the products was not the iron ore which was produced through resolution from discarded cast iron axe, ingot iron. It is probable that to make those steel products, disposed-of cast iron was reused after being molded by decarburizing. Although a few of relics were analyzed for the research, they were of critical importance in defining the process of ironware production from the first century B.C. and the first century A.D. at the Yangsoo-ri region. Judging from the iron from A-19 dwellingsite, it is possible to conclude that the iron was manufactured from cast iron decarburized and yet more research has to be done into relics yetto be exhumed in order to ascertain the finding. All of these findings are believed to play a critical role in further studies to define the steel-manufacturing technique used on the central Korean peninsular in the ancient times.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.45 no.3
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• pp.141-151
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• 2019

Objectives: The outcomes of the treatment of unilateral cleft lip can vary considerably due to variations in repair techniques. The aim of this study was to evaluate and compare treatment outcomes of surgical repair of unilateral cleft lip using either the Tennison-Randall or Millard technique based on (qualitative) parent/subject and professional assessments. Materials and Methods: This was a prospective, randomized, controlled study conducted at Lagos University Teaching Hospital between January 2013 and July 2014. A total of 56 subjects with unilateral cleft lip presenting for primary surgery who satisfied the inclusion criteria were recruited for the study. Subjects were randomly allocated to surgical groups A or B through balloting. Group A underwent cleft repair with the Tennison-Randall technique, while group B underwent cleft repair with the Millard rotation advancement technique. Surgical outcome was assessed using qualitative evaluation by the guardian/subject and independent assessors based on a modified form of the criteria described by Christofides and colleagues. Results: Of the 56 subjects enrolled in this study, 32 were male, with a male to female ratio of 1.3:1. Fifteen of the guardians/subjects in the Tennison-Randall group were most bothered about the lower part of the residual lip scar, while 12 guardians/subjects in the in the Millard group were most bothered about the upper part of the scar. More noses were judged to be flattened in the Millard group than in the Tennison-Randall group. Assessors observed a striking disparity in scar transgression of the philtral ridges between the two groups. Conclusion: Essentially, there were no major difference in the overall results between Millard rotation-advancement and Tennison-Randall repairs. Both Millard and Tennison-Randall's techniques require significant improvements to improve the appearance of the scar on the upper part and lower part of the lip, respectively.

• Journal of Korean Neurosurgical Society
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• v.64 no.5
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• pp.732-739
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• 2021

Objective : Early successful reperfusion is associated with favorable outcomes in acute ischemic stroke (AIS). The purpose of this study was to achieve successful recanalization by a combined mechanical thrombectomy technique, the Aspiration-Retriever Technique for Stroke (ARTS), which is composed of a flexible large lumen distal access catheter and a retrievable stent as the first-line strategy of mechanical thrombectomy. Methods : We retrospectively reviewed 62 patients with AIS who underwent mechanical thrombectomy from 2018 to 2019 at our institute by a senior neurointerventionalist. Among them, patients who were treated using the ARTS technique with the soft torqueable catheter optimized for intracranial access (SOFIA^®; MicroVention-Terumo, Tustin, CA, USA) as the first-line treatment were included. Patients who had tandem occlusions or underlying intracranial artery stenosis were excluded. The angiographic and clinical outcomes were evaluated. The angiographic outcome was analyzed by the rate of successful recanalization, defined as a Thrombolysis in Cerebral Infarction score of 2b or 3 at the end of all procedures and the rate of successfully achieving the first pass effect (FPE), defined as complete recanalization with a single pass of the device. The clinical outcomes included the National Institutes of Health Stroke Scale (NIHSS) score, modified Rankin Scale (mRS), and mortality. Results : A total of 27 patients (mean age, 59.3 years) fulfilled the inclusion criteria. The successful recanalization rate was 96% (n=26) while the FPE rate was 41% (n=11). The mean post-procedural NIHSS change was -3.0. Thirteen patients (48%) showed good clinical outcomes after thrombectomy with the ARTS technique (mRS at 90 days ≤2). Postoperative complications occurred in seven of 25 patients : hemorrhagic transformation in six patients (22%) and distal embolization in one patient (4%). Mortality was 15% (n=4). Conclusion : Although the clinical outcomes using the ARTS technique with a flexible large lumen distal access catheter performed as the frontline thrombectomy in patients with AIS were not significantly superior than those of other studies, this study showed a high rate of successful endovascular recanalization which was comparable to that of other studies. Therefore, ARTS using the SOFIA^® catheter can be considered as the first choice of treatment for AIS due to large vessel occlusion.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.1
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• pp.46-52
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• 2000

Two experiments were conducted to determine ileal digestibilities for the amino acids contained in rapeseed meal using the regression technique and then applying the values obtained, in a growth trial, using growing-finishing pigs. For the digestibility trial, four 20 kg crossbred $(Yorkshire{\times}Landrace{\times}Beijing\;Black)$ barrows were fitted with simple T-cannula in the terminal ileum. After recovery, the barrows were fed one of four experimental diets according to a $4{\times}4$ Latin Square design. The pigs were fed corn-soybean meal based diets supplemented with 0, 25, 50 or 75% rapeseed meal. For the growth trial, 80 crossbred $(Yorkshire{\times}Landrace{\times}Beijing\;Black)$ growing pigs $(20{\pm}2.4kg)$ were fed corn-soybean meal diets supplemented with 0, 3, 6, 9 or 12% rapeseed meal. Four pens (2 gilts and 2 castrates) were assigned to each treatment. With the exception of isoleucine and methionine, the digestibility coefficients for the indispensible amino acids declined as the level of rapeseed meal in the diet increased. There was little agreement between the amino acid digestibilities determined with the regression technique and values previously published for rapeseed meal. During the growing (22-42 kg) period, the addition of rapeseed meal had no significant effects on gain, feed intake or feed conversion. During the finishing period (58-91 kg), daily gain was not affected by rapeseed meal inclusion but feed conversion declined (p<0.04) as the level of rapeseed meal in the diet increased.

• Journal of the Korean Society for Nondestructive Testing
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• v.31 no.2
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• pp.150-156
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• 2011

In this paper, infrared thermography measurement technique has been used to develop standard measurement technique for nondestructive testing of composite materials which is widely used in aerospace industries. To increase the defect detection rate, the related experiment used the lock-in IR-thermographiy method. Therefore it is of considerable interest in the field of non-destructive testing for fast discontinuity detection by using ultrasonic lock-in infrared thermography. The result also shows that as the investigation period of light source is lengthened according to the thickness of specimen, the possibility of detecting defects gets higher as well. However, the reason why the result values were not favorable when less than 50 mHz of light source was provided is because it was difficult to detect defects as the defect parts became a state of thermal equilibrium in general when thermal diffusivity affects the entire materials.

• Journal of Ocean Engineering and Technology
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• v.4 no.1
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• pp.88-100
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• 1990

Among the test methods to evaluate stress-corrosion cracking(SCC) on the basis of fracture mechanics, constant displacement(bolt) loading method using modified-WOL specimen is practically convenient. In this test method, compliance formula is generally required to calculate load(consequently $K_{ISCC}$). There are many problems in using the analytic compliance formula to calculate $K_{ISCC}$, so we had proposed the experimental $K_{ISCC}$ evaluation technique in the previous report. This study has employed the slightly altered configuration of modified-WOL specimen made of weldable structural stee(BS360-50D). With these specimens, stress-corrosion tests have been performed in $H_2S$ gas saturated 20% HCl solution. Through the test, the problems as mentioned earlier have been discussed again, and the proposed evaluation technique has been verified. And the stress-corrosion cracks and hydrogen blisters have been investigated in the initiation step with the aids of metallurgical micrographs, SEM fractographs, and EPMA analysis. The inclusions segregated in the mid-thickness region traps hydrogen to produce the hydrogen blistering. The applied or residual stress does not contribute the occurrence of the blister. Hydrogen absorbed into the mid-thickness region is consumed to produce the blistering so that stress-corrosion crack could hardly be detected at that region. The stress-corrosion cracks initiate from the inclusions and propagate in radial pattern. And the initiation site is remote from the crack tip and is inclined from the crack plane, which is assumed to be caused by the triaxial stress and the amount of the absorbed hydrogen.

• The Korean Journal of Applied Statistics
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• v.31 no.5
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• pp.621-636
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• 2018

Research on the application of informative sampling technique has been conducted in order to reduce the influence of non-response. Chung and Shin (Korean Journal of Applied Statistics, 30, 993-1004, 2017) showed that the estimation accuracy improved when using exponential response rate information for the parameter estimation if the distribution of errors included in the super population model follows normal distribution. However this method divides the stratum into equally spaced substrata to obtain the sample weight of the informative sampling technique and shows that the accuracy of the estimation improves as the number of substrata increases. In this study, with the given number of total sample size, the optimal substratum boundary points are calculated using equal space, quantile, and LH algorithm; consequently, the results using those methods are compared through simulation. We also studied the criteria to determine the number of substrata and substratum boundaries that can be used in practice with various types of auxiliary variable distributions.

• Journal of Acupuncture Research
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• v.34 no.4
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• pp.190-196
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• 2017

Background: The purpose of this study was to investigate the efficacy of muscle energy techniques (MET) of upper trapezius and sternocleidomastoid muscles on Bell's palsy. Methods: In this retrospective study, we screened the medical records of patients with Bell's palsy who had received inpatient and outpatient treatment at the Department of Acupuncture & Moxibustion, Korean Medicine Hospital Dong-Eui University between November 28, 2016 and April 30, 2017. A total of 34 out of 93 Bell's palsy patients met the inclusion criteria. The 34 patients were divided into two groups: Group A patients had undergone Korean-Western combination treatment and MET of upper trapezius and sternocleidomastoid muscles; Group B patients had undergone Korean-Western combination treatment only. MET of upper trapezius and sternocleidomastoid muscles had been performed three times a week during the inpatient period, and two to three times a week during the outpatient period. Yanagihara scores had been assessed at the first visit, and 1, 2, 3, and 4 weeks after the first visit. Results: Group A Yanagihara scores were significantly improved during each interval from the first visit to 4 weeks later. Group B Yanagihara scores were also significantly improved except during the first week. During every period, the improvements observed in Yanagihara score were significantly higher in Group A than in Group B. Conclusion: These results suggest that MET of upper trapezius and sternocleidomastoid muscles may be effective treatment for Bell's palsy.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.9
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• pp.4457-4461
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• 2016

Purpose: To determine the prevalence of abnormal cervical cytology, as diagnosed using a liquid-based cytology technique, in pregnant women attending the Antenatal Care (ANC) clinic at Siriraj Hospital. Materials and Methods: This cross-sectional study included 655 first-visit pregnant women who attended ANC clinic at Siriraj Hospital during June to November 2015 study period. After receiving routine antenatal care, cervical cytology screening was performed with the Siriraj liquid-based cytology technique. All specimens were reviewed by a certified cytopathologist using Bethesda System 2001 criteria. Patients with abnormal PAP results characterized as epithelial cell abnormalities were referred to a gynecologic oncologist for further management according to ASCCP Guidelines 2012. Results: Mean age of participants was $28.9{\pm}6.2$ years. Prevalence of abnormal cervical cytology was 3.4% (95% CI: 2.0-4.7). Among this group, there were ASC-US, ASC-H, LSIL, HSIL for 12(1.8%), 2(0.3%), 7(1.1%) and 1(0.2%), respectively. In 633 specimens of the normal group, infection was identified in 158 specimens (24.1%) which were caused by Candida spp. and Trichomonas vaginalis. Regarding patient perception about the importance of cervical cancer screening, although most women perceived screening to be important, 54% of participants had never been screened for cervical cancer. Rate of loss to follow-up in the postpartum period was as high as 41.8%. Conclusions: Prevalence of abnormal cervical cytology in pregnant women attending the ANC clinic at Siriraj Hospital was 3.4%. Inclusion of cervical cancer screening as part of antenatal assessment can help to identify precancerous lesions or cervical cancers in patients who might otherwise not be screened, thereby facilitating early treatment and improved patient outcomes.