• Clean Technology
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• v.23 no.3
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• pp.286-293
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• 2017

The goal of this paper was to improve the performance of the adsorbent to remove $H_2S$. Pellet type adsorbents were prepared by using four kinds of materials ($Fe_2O_3$, $Ca(OH)_2$, Activated carbon, $Al(OH)_2)$ for use as a basic carrier. As the results of $H_2S$ adsorption tests, $Fe_2O_3$ and Activated Carbon improved the adsorption performance of $H_2S$ by 1.5 ~ 2 times, and $Ca(OH)_2$ and $Al(OH)_2$ showed no effect on $H_2S$ adsorption performance. Four basic materials were as carriers, and 5 wt% of KI, KOH and $K_2CO_3$ were added on the carriers, respectively. As the results of $H_2S$ adsorption tests, adsorbent containing $K_2CO_3$ showed the best performance. As a result of $H_2S$ adsorption test with varying $K_2CO_3$ content from 5 to 30 wt%, it was confirmed that adsorption performance was increased up to 20 wt% of $K_2CO_3$ and adsorption performance decreased to 30 wt%. The $H_2S$ adsorption performance was modeled by using Thomas model with varying $K_2CO_3$ contents and the results were used for the adsorption tower design. It was shown that the experimental values and the simulated values were in good agreement with the contents range of $K_2CO_3$ up to 20 wt%. Based on these results, it is expected that not only the adsorption performance of $H_2S$ adsorbent is improved but also life time of the adsorbent is increased.

• Journal of Energy Engineering
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• v.25 no.4
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• pp.103-109
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• 2016

Polyethylene pipes has useful benefits which are anti-corrosive and flexible material, so it is used to gas pipes but also class 3 water pipes of nuclear power plant, process pipes of petrochemical plant and chemical plant. So the usage of polyethylene pipes is widely increased. But it has been limited for the usage of polyethylene, because it can not be directly detected to fusion joints by using non destructive evaluation. Polyethylene pipes are connected by two methods, one is butt fusion and the other is electrofusion. Butt fusion is widely used to connecting the pipes. It is proposed to method for determining the reliability of joints in this study that is detection of the melt flow zone at fusion joints. In this study, middle density polyethylene is used, outside diameter of the test specimen is 225mm and thickness is 20.5mm. Speed of ultrasonic of this test specimen is 2,200m/s. Test specimens were fabricated by varying the heating time which means from 0% to 130% applying time through heating plate to polyethylene for detecting melt flow zone. Also 4 additional test specimens were made, one was made that not scrapping attached surface of pipes but applying 100% of the proper heating time and the others were made to include of soil, gravel and vinly tape paper at fusion joints, that were also applied 100% of proper heating time. Ultrasonic testing to measure the melt flow zone of 20 test specimens was conducted by using 3.5MHz and 5.0MHz ultrasonic probes and melt flow zone measuring was conducted to three times at different point to one specimen. To differentiate the melt flow zone signal, post image processing was equally conducted to all test results and image levels, contrast, sharpen, threshold were adopted to all teat results and the test results were displayed gray scale. From the results, for the shorter heating times the reflection area of multiple echo have been increased, so the data was obtained from the position where it can be eliminated as much as possible. At 80% of proper heating time(168 sec.), the signal of melt flow zone was obtained clearly, so measuring could be conducted. From 7% of proper heating time(15 sec.) to shorter heating times. we could not obtain the signal because test specimen was not fused. From the result, we can verify that measuring of melt flow zone by using phased array ultrasonic imaging method is possible. And we can verify to complete and incomplete butt fusion by measuring the melt flow zone.

• Radiation Oncology Journal
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• v.20 no.2
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• pp.123-129
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• 2002

Purpose : The purpose of this study 띤as to determine the potential role of three-dimensional conformal radiotherapy (3D-CRT) in the treatment of primary unresectable hepatocellular carcinoma. The preliminary results on the efficacy and the toxicity of 3D-CRT are reported. Materials and Methods : Seventeen patients were enrolled in this study, which was conducted prospectively from January 1995 to June 1997. The exclusion criteria included the presence of extrahepatic metastasis, liver cirrhosis of Child-Pugh classification C, tumors occupying more than two thirds of the entire liver, and a performance status of more than 3 on the ECOG scale. Two patients were treated with radiotherapy only while the remaining 15 were treated with combined transcatheter arterial chemoembolization. Radiotherapy was given to the field including the tumor plus a 1.5 cm margin using a 3D-CRT technique. The radiation dose ranged from $36\~60\;Gy$ (median; 59.4 Gy). Tumor response was based on a radiological examination such as the CT scan, MR imaging, and hepatic artery angiography at $4\~8$ weeks following the completion of treatment. The acute and subacute toxicities were monitored. Results : An objective response was observed in 11 out of 17 patients, giving a response rate of $64.7\%$. The actuarial survival rate at 2 years was $21.2\%$ from the start of radiotherapy (median survival; 19 months). Six patients developed a distant metastasis consisting of a lung metastasis in 5 patients and bone metastasis in one. The complications related to 30-CRT were gastro-duodenitis $(\geq\;grade\;2)$ in 2 patients. There were no treatment related deaths and radiation induced hepatitis. Conclusion : The preliminary results show that 3D-CRT is a reliable and effective treatment modality for primary unresectable hepatocellular carcinoma compared to other conventional modalities. Further studies to evaluate the definitive role of the 3D-CRT technique in the treatment of primary unresectable hepatocellular carcinoma are needed.

• Investigative Magnetic Resonance Imaging
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• v.6 no.2
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• pp.129-136
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• 2002

Purpose : To evaluate the usefulness of MRCP in the diagnosis of the variable causes of common bile duct(CBD) dilatation, except stone or tumor Materials and methods : Twenty-six patients(M:F=15:11, mean age; 62 years) with both MRCP and ERCP were included in this study. Dynamic MRCP(n=12) and contrast-enhanced MRI(n=10) of abdomen were also added. Dilatation of CBD, intrahepatic ducts and pancreatic duct was evaluated, including coexistence of intrahepatic ductal stone, pancreatic pseudocyst, and papillary or papillary edema. The criteria of CBD dilatation was over than 7mm(n= 21, without cholecystectomy) or 10 mm(n=5, with cholecystecto-my) in diameter on T2-weighted coronal image. Results : The mean diameter of CBD was 12.7mm without cholecystectomy(9-19 mm) and 13.0 mm with cholecystectomy(10-15mm), respectively(p 〉0.05). Cholangitis(n=11, 42.3%), chronic pancreatitis(n=8, 30.8%), stenosis of distal CBD(n= 6, 23.1%), periampullary diverticulum(n=3, 11.5%), stenosis of ampulla of Vater(n=2, 7.7%), dysfunction of sphincter of Oddi(n=2, 7.7%), acute focal pancreatitis in the pancreatic head(n=2, 7.7%), papillitis(n=1, 3.8%), pseudocyst in the pancre atic head(n = 1, 3.8%), and ascaris in CBD(n=1, 3.8%) were noted. Pancreatic duct dilatation(n=10, 38.5%) and duodenal diverticulum(n=3, 11.5%) were also seen on MRC P. On dynamic MRCP(12 patients), distal CBD was visualized in 2 patients(16.7%), which was not shown on routine MRCP. Only 1 patient(10.0%) showed papillitis with slightly enhancing papilla on contrast-enhanced MRI (10 patients). Conclusion : MRCP was thought to be helpful in the evaluation of the causes of CBD dilatation, not caused by stone or tumor, especially in the cases of stenosis of distal CBD and chronic pancreatitis, dysfunction of sphincter of Oddi on dynamic MRCP and cholangitis and pericholangitic abnormality on contrast-enhanced MRI.

• Journal of the Korean Geographical Society
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• v.29 no.3
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• pp.266-280
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• 1994

Upper-air synoptic data and surface weather elements such as temperature, relative humidity, wind speed, cloud and precipitation were analyzed in some detail to determine the characteristics of Nopsae, a foehn-like surface wind over the Youngsuh region of Central Korea. NOAA AVHRR and GMS images are also referenced to identify the distribution of clouds and precipitation to classify the tpyes of foehn over the study area. The data period examined is from 1982 until 1993 of spring and summer months from March through August. Results of the anaylsis are as follows. Warm and dry air penetration over the Younesuh region has experienced on foehn days occured between March 21 and August 10 during study perion. The mean annual number of foehn the days were 28. Foehn phenomena were prominent during March 21-25, April 5-15, May 25-June 10, and June 26-30 pentads. The intensity of the phenomena can be evaluated as the difference of daily maximum temperature and relative humidity between windward sites and leeward sites. The intensity of daily maximum temperature reached 14.5$^{\circ}C$, but most values were in the range of 5.0-7.5$^{\circ}C$ (61%). Although strong intensity of foehns usually develop in June, it is common that farmers in the region experince more aridity during the foehnday of April and May due to the transplantation of rice seedlings. Long-run foehn are not common phenomena and 55% of foehn terminate in one day, but there is a record that Nopsae persisted up to 9 days continuously. The author identified using the cloud and precipitation data out of NOAA-11, AVHRR and GMS images is that one of them has no precipitation over windward side. The available data and the results of the analysis are somewhat inadequate. Since the results imply that wave phenomenon is potentially important in terms of local surface weather and vertical momentum transport, more detailed theoretical and observational studies are necessary to clarify the mechanism and the impacts of Nopsae.

• Journal of radiological science and technology
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• v.29 no.4
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• pp.249-255
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• 2006

Purpose: The diagnostic utility of fluorine-18 2-deoxy-D-glucose positron emission tomograhpy ($^{18}F-FDG $PET) for the non-invasive differentiation of focal lung lesions originated from cancer or inflammation disease by combined visual image interpretation and semi-quantitative uptake value analysis has been documented. In general, Standardized Uptake Value(SUV) is used to diagnose lung disease. But SUV does not contain dynamic information of lung tissue for the glucose. Therefore, this study was undertaken to hypothesis that analysis of dynamic kinetics of focal lung lesions base on $^{18}F-FDG$ PET may more accurately determine the lung disease. So we compared Time Activity Curve(TAC), Standardized Uptake Value-Dynamic Curve(SUV-DC) graph pattern with Glucose Metabolic Rate(MRGlu) from Patlak analysis. Methods: With lung disease, 17 patients were examined. They were injected with $^{18}F-FDG$ over 30-s into peripheral vein while acquisition of the serial transaxial tomographic images were started. For acquisition protocol, we used twelve 10-s, four 30-s, sixteen 60-s, five 300-s and one 900-s frame for 60 mins. Its images were analyzed by visual interpretation TAC, SUV-DC and a kinetic analysis(Patlak analysis). The latter was based on region of interest(ROIs) which were drawn with the lung disease shape. Each optimized patterns were compared with itself. Results: In TAC patterns, it hard to observe cancer type with inflammation disease in early pool blood area but over the time cancer type slope more remarkably increased than inflammation disease. SUV-DC was similar to TAC pattern. In the result of Patlak analysis, In time activity curve of aorta, even though inflammation disease showed higher blood activity than cancer, at first as time went by, blood activity of inflammation disease became the lowest. However, in time activity curve of tissue, cancer had the highest uptake and inflammation disease was in the middle. Conclusion: Through the examination, TAC and SUV-DC could approached the results that lung cancer type and inflammation disease type has it's own difference shape patterns. Also, it has outstanding differentiation between cancer type and inflammation in Patlak and MRGlu analysis. Through these analysis methods, it will helpful to separation lung disease.

• Childhood Kidney Diseases
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• v.18 no.2
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• pp.64-70
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• 2014

Purpose: The aims of this study were to assess the clinical and laboratory profiles of chronic kidney disease-mineral bone disorder (CKD-MBD) and to assess the effects of treatment of active vitamin D analogs on severe hyperparathyroidism (SHPT) in pediatric patients on chronic peritoneal dialysis. Methods: This is a retrospective study included 53 patients who had been undergoing dialysis for more than 1 year, between January 2003 and December 2012. Results: Even after treatment with phosphate binders and active vitamin D analogs, the $mean{\pm}standard$ deviation of the percentage of time during peritoneal dialysis that the patients' serum concentrations of phosphorus, corrected total calcium, and parathyroid hormone (PTH) fell within the Kidney Disease Outcomes Quality Initiative recommended ranges was $25.06{\pm}17.47%$, $53.30{\pm}23.03%$, and $11.52{\pm}9.51%$, respectively. Clinical symptoms or radiological signs of CKD-MBD were observed in 10 patients (18.9%). There were significant differences in percentage of time that the serum intact PTH concentration was outside of the recommended range between patients with and without symptoms or signs of CKD-MBD (below recommended range, $11.74{\pm}7.37%$ vs. $40.77{\pm}25.39%$, P <0.001; above the recommended range, $63.79{\pm}27.86%$ vs. $37.09{\pm}27.76%$, P =0.022). Of the 25 patients with SHPT, high-dose alfacalcidol treatment was required in 13 patients that controlled SHPT in 7 of these patients, without marked complications. Conclusion: Despite our efforts to manage CKD-MBD, patients' met the recommended ranges from relevant guidelines at a low frequency. The treatment of high-dose active vitamin D analogs was required in about half of the patients with SHPT and effective in about half of them.

• Journal of radiological science and technology
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• v.33 no.1
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• pp.19-24
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• 2010

The aim of this study was to evaluate the change of bone mineral density according to distal radius rotation and the correlations of the lowest BMD measured by DXA at the lumba versus distal radius. The eleven males were projected distal radius by DR X-ray and the measurement of BMD by DXA of the appropriate position of the forearm were performed on 21 males. The healthy 11 and 21 volunteers without any history of operations, anomalies, or trauma were enrolled. The experiment was performed by two methods. First, The DR X-ray was measured distal radius of 11 males in pronation and supination with three, six and nine degrees, including a neutral position. The ROI was measured by the m-view program on the PACS monitor. Second, The DXA was measured distal radius of 21 males in pronation and supination with five and ten degrees, including a neutral position to evaluate the changes of BMD according to the rotation. A correlation of the BMD in the distal radius with BMD that lumbar spine was performed, along with analysis of the data by SPSS 12.0v. The mean rotation angle of the distal radius about eleven males DR X-ray measured $7^{\circ}$ of pronation (82%, n = 9), $6^{\circ}$ of supination and $0^{\circ}$ of neutral of (9%, n = 1), The total average rotation angle in 11 male was $5.1^{\circ}$ of pronation. The rotation angle of the distal radius about twenty one males on DXA measured $7.2^{\circ}$ of pronation (43%, n = 9), $7^{\circ}$ of supination (24%, n = 5), and $0^{\circ}$ of neutral (33%, n = 7), The total average rotation angle in 21 people was $4.1^{\circ}$ of pronation. The correlation of the analysis of lumba and distal radius were r = 3.0, p = 0.18. consequently, The correlation was not significance. Because BMD of lumba was not coverd for BMD of the distal radius, with a neutral position, Pronation is needed for BMD in the distal radius with the rotation angle measuring at the lowest BMD. the rotation angle about five degrees of pronation of the distal radius is recommended.

• Korean Journal of Ecology and Environment
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• v.46 no.1
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• pp.33-40
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• 2013

From March 2012 to January 2013, this study was conducted as a part of the project for making a precise electronic ecological zoning map of vegetation on a highly reduced scale of 1 to 5,000 with a view to improving management efficiency of national parks and enlarging the availability of the data produced from the basic research monitoring the resources of national parks. For the research accuracy and rapidity, a vegetation map was specially created for the on-the-site-vegetation research. To make the map more meticulous, we categorized the vegetation database into five groups: broadleaved forest, coniferous forest, mixed forest, rock vegetation and miscellaneous one. After comparing the results of the data built for the vegetation research and the actual research findings, it was made clear that vegetation of both categories was almost the same in case of broad-leaved forest with 72.20% and 78.45% respectively, and also equivalent in other groups like, for example, coniferous forest (16.70%, 13.41%), mixed forest (9.50%, 7.49%) and rock vegetation (0.60%, 0.15%). According to the precise vegetation map produced from the research, the deciduous broad-leaved forest was the most widely prevalent type in the correlated hierarchical classification of vegetation, occupying 65.78% of the overall vegetation. It was followed by mountain valley forest (15.17%), coniferous forest (10.90%), and plantation forest (7.00%) in order. It is particularly noteworthy that Mt. Deogyusan national park has retained a very stable and versatile forest vegetation in the outstanding state since approximately 20% of the mountain turns out to belong to the I grade vegetation conservation classification which contains climax forests, unique vegetation, subalpine vegetation, matured stands which are older than 50 years and etc.

• Journal of Korean Society for Geospatial Information Science
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• v.8 no.1 s.15
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• pp.51-63
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• 2000

Dynamic traffic assignment(DTA) has been a topic of substantial research during the past decade. While DTA is gradually maturing, many aspects of DTA still need improvement, especially regarding its formulation and solution algerian Recently, with its promise for In(Intelligent Transportation System) and GIS(Geographic Information System) applications, DTA have received increasing attention. This potential also implies higher requirement for DTA modeling, especially regarding its solution efficiency for real-time implementation. But DTA have many mathematical difficulties in searching process due to the complexity of spatial and temporal variables. Although many solution algorithms have been studied, conventional methods cannot iud the solution in case that objective function or constraints is not convex. In this paper, the genetic algorithm to find the solution of DTA is applied and the Merchant-Nemhauser model is used as DTA model because it has a nonconvex constraint set. To handle the nonconvex constraint set the GENOCOP III system which is a kind of the genetic algorithm is used in this study. Results for the sample network have been compared with the results of conventional method.