Transactions of the Korean Society of Mechanical Engineers B
In the gas wiping process of continuous hot-dip galvanizing, edge overcoating develops near the e... more In the gas wiping process of continuous hot-dip galvanizing, edge overcoating develops near the edge of the steel strip. The overcoating is supposed to occur due to the reduced impact pressure of wiping gas on the strip surface. The purpose of this study is to investigate the effect of edge vortex on the reduced impact pressure. Three-dimensional unsteady flows are simulated using a commercial code, STAR-CD. Standard k- model is used as a turbulence model. It is found that an alternating vortex structure in the vicinity of strip edge is developed by buckling of opposed jet streams and that the reduced amount of impact pressure at strip edge becomes smaller as the air knife gets closer to the strip. The effect of edge baffle on the reduced impact pressure is also investigated.
This paper presents experimental results on the recycling aluminum wire used in the actual field.... more This paper presents experimental results on the recycling aluminum wire used in the actual field. Several tests were carried out with the recycled aluminum wires to prove that they are reusable. Mechanical, electrical and oxidation properties of recycled and new ACSR 160 mm2 were compared after 7.5 years service aging in the salt contaminated areas of the Korean peninsular
Although the liver is the most common site for pancreatic islet transplantation, it is not optima... more Although the liver is the most common site for pancreatic islet transplantation, it is not optimal. We compared kidney, liver, muscle, and omentum as transplantation sites with regard to operative feasibility, and the efficiency of implantation and glycemic control. Islets from C57BL/6 mice were transplanted into diabetic syngeneic recipients. The mean operative time and mortality were measured to assess feasibility. To assess implantation efficiency, the marginal mass required to cure diabetes and the mean time taken to achieve normoglycemia were measured. A glucose tolerance test was performed to assess glycemic control efficiency. The data are listed in the order of the kidney, liver, muscle, and omentum, respectively. The mean mortality rate was 6.7, 20.0, 7.1, and 12.5%; the mean operative time was 10.2, 27.4, 11.2, and 19.8 min; the marginal islet mass was 100, 600, 600, and 200 islet equivalence units and the mean time to reach euglycemia was 3.0, 15.1, 26.6, and 13.9 days. T...
Continuous efforts have been made by the organ donation and transplantation community in Korea to... more Continuous efforts have been made by the organ donation and transplantation community in Korea to increase organ donation by the deceased. The authors detailed trends of organ donation and utilization over the past 10 yr using data provided by the KONOS. The yearly number of deceased donors has grown gradually since 2003. The number and percentage of old donors (> or = 50 yr) and donors dying from intracranial hemorrhage has increased continuously. Therefore, the percentage of standard criteria donors (SCD) has been declining significantly, from 94% in 2000 to 79.2% in 2009. The number of organs transplanted per donor (OTPD) has also declined slightly since 2007, from 3.28 in 2007 to 2.95 in 2009. This decline may be attributable to increases in the number and percentage of extended criteria donors (ECD) and donors after cardiac death (DCD), since the OTPD was 2.25 for DCD, 2.5 for ECD, and 3.09 for SCD in 2009. In summary, the makeup of donors has changed significantly. There is...
Tailoring of semiconducting metal oxide nanostructures, which possess controlled pore size and co... more Tailoring of semiconducting metal oxide nanostructures, which possess controlled pore size and concentration, is of great value to accurately detect various volatile organic compounds in exhaled breath, which act as potential biomarkers for many health conditions. In this work, we have developed a very simple and robust route for controlling both the size and distribution of spherical pores in electrospun WO3 nanofibers (NFs) via a sacrificial templating route using polystyrene colloids with different diameters (200 nm and 500 nm). A tentacle-like structure with randomly distributed pores on the surface of electrospun WO3 NFs were achieved, which exhibited improved surface area as well as porosity. Porous WO3 NFs with enhanced surface area exhibited high gas response (Rair/Rgas = 43.1 at 5 ppm) towards small and light H2S molecules. In contrast, porous WO3 NFs with maximized pore diameter showed a high response (Rair/Rgas = 2.8 at 5 ppm) towards large and heavy acetone molecules. Further enhanced sensing performance (Rair/Rgas = 65.6 at 5 ppm H2S) was achieved by functionalizing porous WO3 NFs with 0.1 wt% non-oxidized graphene (NOGR) flakes by forming a Schottky barrier (ΔΦ = 0.11) at the junction between the WO3 NFs (Φ = 4.56 eV) and NOGR flakes (Φ = 4.67 eV), which showed high potential for the diagnosis of halitosis.
Ž. Ž. Ž. Multiseeding with 100 r 100 grain junctions of top-seeded melt growth TSMG processed YBC... more Ž. Ž. Ž. Multiseeding with 100 r 100 grain junctions of top-seeded melt growth TSMG processed YBCO superconductors was studied. Multiple seeding shortened the processing time for the fabrication of TSMG-processed YBCO superconductors. The relationship among the number of seeds, the levitation forces and the trapped magnetic fields of the TSMG-processed Ž. Ž. YBCO samples is reported. The characteristic of the 100 r 100 grain junction is discussed in terms of a wetting angle of a melt.
The effects of the distance d between two Sm Ba Cu O seeds on the characteristics of the 100 r 10... more The effects of the distance d between two Sm Ba Cu O seeds on the characteristics of the 100 r 100 junctions 1.8 2.4 3.4 x Ž. of top-seeded melt growth TSMG processed YBCO superconductors were investigated. The trapped magnetic field at the grain junction and the levitation force of the top surface decreased with increasing d value. The degradation of the Ž. properties was discussed in terms of the presence of the residual melt-forming phases CuO and BaCuO at the grain 2 junction.
Ž. Ž. The growth nature of YBa Cu O Y123 grains at the top surfaces of top-seeded melt growth TSM... more Ž. Ž. The growth nature of YBa Cu O Y123 grains at the top surfaces of top-seeded melt growth TSMG processed 2 3 7 yy YBCO superconductors was studied in respect to the dimension of Sm Ba Cu O seeds. The top surface growth mode 1.8 2.4 3.4 x was significantly dependent on the dimensions of the seed, especially on the seed thickness. The use of thin slab-like Sm-seeds led to the nucleation of undesirable subsidiary Y123 grains at the seeded area, while such subsidiary nucleation was hardly observed when thick seeds were used. The formation mechanism of the subsidiary Y123 grains, and the effects on the levitation forces and trapped magnetic field are discussed.
Abdominal aortic aneurysms in neonates and infants are rare and are usually associated with infec... more Abdominal aortic aneurysms in neonates and infants are rare and are usually associated with infection, vasculitis, connective tissue disorder, or iatrogenic trauma such as umbilical catheterization. An idiopathic congenital abdominal aortic aneurysm is the least common category and there are few descriptions of the imaging features. We present the antenatal and postnatal imaging findings of an idiopathic congenital abdominal aortic aneurysm including the findings on US, MRI and CT.
Ex situ electrokinetic (EK) bioremediation of a laboratory-prepared pentadecane-contaminated kaol... more Ex situ electrokinetic (EK) bioremediation of a laboratory-prepared pentadecane-contaminated kaolinite was carried out. Extraneous bacteria and ionic nutrients were continuously supplied to the soil specimen by a new electrolyte circulation method, which controlled electrical pH change of electrolyte solution to keep bacterial activity. During the EK bioremediation the anode region showed the highest colony forming unit (CFU) due to electrical attraction between anode and bacteria. Simultaneous increases of CFU and uniform pentadecane removal in most soil regions demonstrated that electro-osmosis as well as electrophoresis affected the bacterial transport in soil. At 3.13 mA/cm2, increase in soil temperature to above 45 degrees C inhibited bacterial activity, which caused the decrease of removal efficiency. The removal amount of pentadecane increased with initial pentadecane concentration at the same current densities (0.63 and 1.88 mA/cm2) because of the increased amount of weakly bound pentadecane onto the soil surface. The highest removal efficiency (77.6%) was obtained at 0.63 mA/cm2 for 1000 mg/kg pentadecane after 14 days. Consequently, the present methods of EK bioremediation demonstrated superiority over the conventional bioremediation, which had inherent demerits of slow degradation and low removal efficiency.
We report a case of cerebral lipiodol embolism after transarterial chemoembolization of hepatocel... more We report a case of cerebral lipiodol embolism after transarterial chemoembolization of hepatocellular carcinoma, which was confirmed by dual-energy computed tomography (CT). A 44-year-old male patient developed left leg weakness after transarterial chemoembolization for hepatocellular carcinoma. The noncontrast CT scan of his brain revealed multiple high-attenuating lesions scattered along the gyral surface of the both cerebral hemispheres; meanwhile, the lesions disappeared on the iodine-removed virtual noncontrast images generated from dual-energy CT.
Two cases of contrast media extravasation of a ruptured aneurysm during computed tomography angio... more Two cases of contrast media extravasation of a ruptured aneurysm during computed tomography angiography (CTA) are described. The contrast media extravasation appeared as a highly attenuated twisted ribbon-like structure originating from the aneurysmal dome, and this mimicked a vascular structure. Because rebleeding of an aneurysm is accompanied by disastrous consequences, it is important to understand the imaging feature of active bleeding on CTA.
IEEE Transactions on Appiled Superconductivity, 2001
... Overpowering Quenches Hyo-Sang Choi, Hye-Rim Kim, Ok-Bae Hyun and Sang-Joon Kim ... X-ray dif... more ... Overpowering Quenches Hyo-Sang Choi, Hye-Rim Kim, Ok-Bae Hyun and Sang-Joon Kim ... X-ray diffraction and Rutherford backscattering spectroscopy data did not change considerably after repeated quenches but some minor change appeared. ...
Microchimerism is a state in which a low percentage (Ͻ 1%) of hematopoietic cells from donor orig... more Microchimerism is a state in which a low percentage (Ͻ 1%) of hematopoietic cells from donor origin persists in the recipient after solid organ transplantation or transfusion. We have developed a highly specific method using nested PCR-SSCP (single strand conformation polymorphism) analysis. Methods: We created an artificial microchimerism ranging from 1% to 0.00001% using DNA samples of UCLA DNA Exchange Program with known HLA-DRB1 allelic types. For nested PCR, generic amplification of the exon 2 of HLA DRB1/3/4/5 gene was carried out, followed by DRB1 group specific PCR (DR1ϳDR16) using a 1:200 dilution of the first PCR product. Presence of specific DRB1 alleles was detected by SSCP analysis of denatured (single stranded) 2nd PCR product. Results: Detection of microchimerism at the level of Յ0.01% was possible for all of the 25 HLA-DRB1 alleles tested using nested PCR-SSCP method, and detection sensitivity was Յ0.001% for several alleles tested. Conclusions: Nested PCR-SSCP is a highly specific and reasonably sensitive method for the detection of HLA-DRB1 microchimerism.
The majority of newly acquired nonhuman primates encounter serious problems adapting themselves t... more The majority of newly acquired nonhuman primates encounter serious problems adapting themselves to new environments or facilities. In particular, loss of appetite and abnormal behavior can occur in response to environmental stresses. These adaptation abnormalities can ultimately have an affect on the animal's growth and well-being. In this study, we evaluated the affects of a puzzle feeder on the food intake and abnormal behavior of newly acquired rhesus monkeys for a short period. The puzzle feeder was applied to 47to 58-month-old animals that had never previously encountered one. We found that there was no difference in the change of food intake between the bucket condition and the puzzle feeder condition. In contrast, the time spent for consumption of food was three times longer in the puzzle feeder condition than in the bucket condition. Two monkeys initially exhibited stereotypic behavior. One showed a decreasing, and the other an increasing pattern of abnormal behavior after introduction of the puzzle feeder. In conclusion, this result suggests that over a short period, the puzzle feeder can only affect the time for food consumption since it failed to affect the food intake and did not consistently influence stereotypic behaviors in newly acquired rhesus monkeys.
Removal characteristics of polycyclic aromatic hydrocarbons (PAHs) from low-permeable soil using ... more Removal characteristics of polycyclic aromatic hydrocarbons (PAHs) from low-permeable soil using a surfactant-enhanced electrokinetic (EK) process were investigated. Phenanthrene and kaolinite were selected as a representative PAH and a model soil. A ...
... value more rapidly than at 100 V, because the migrational flux of ions was in proportion to e... more ... value more rapidly than at 100 V, because the migrational flux of ions was in proportion to electrical potential gradient or cell voltage (Acar and Alshawabkeh, 1993). ... 3, the apparent conductivity was calculated from the change of current across the electrodes (Hamed et al., 1991 ...
An alternative distributional assumption is proposed for the stochastic volatility model. This re... more An alternative distributional assumption is proposed for the stochastic volatility model. This results in extremely flexible tail behaviour of the sampling distribudon for the observables, as well as in the availability of a simple Markov Chain Monte Carlo strategy for posterior analysis. By allowing the tail behaviour to be determined by a separate parameter, we reserve the parameters of the volatility process to dictate the degree of volatility clustering. Treatment of a leverage effect and a mean function are formally integrated in the analysis. Some empirical examples on both stock prices and exchange rates clearly indicate the presence of fat tails, in combination with high levels of volatility clustering. In addition, we find that prefiltering the data through imposing a particular mean function can be quite hazardous for inference on volatilities. Acknowledgements: The author acknowledges the hospitality of CORE where part of this work was done. Comments from Carmen Femández, Theo Nijman and Jacek Osiewalski proved very helpful. The usual disclaimer applies.
Transactions of the Korean Society of Mechanical Engineers B
In the gas wiping process of continuous hot-dip galvanizing, edge overcoating develops near the e... more In the gas wiping process of continuous hot-dip galvanizing, edge overcoating develops near the edge of the steel strip. The overcoating is supposed to occur due to the reduced impact pressure of wiping gas on the strip surface. The purpose of this study is to investigate the effect of edge vortex on the reduced impact pressure. Three-dimensional unsteady flows are simulated using a commercial code, STAR-CD. Standard k- model is used as a turbulence model. It is found that an alternating vortex structure in the vicinity of strip edge is developed by buckling of opposed jet streams and that the reduced amount of impact pressure at strip edge becomes smaller as the air knife gets closer to the strip. The effect of edge baffle on the reduced impact pressure is also investigated.
This paper presents experimental results on the recycling aluminum wire used in the actual field.... more This paper presents experimental results on the recycling aluminum wire used in the actual field. Several tests were carried out with the recycled aluminum wires to prove that they are reusable. Mechanical, electrical and oxidation properties of recycled and new ACSR 160 mm2 were compared after 7.5 years service aging in the salt contaminated areas of the Korean peninsular
Although the liver is the most common site for pancreatic islet transplantation, it is not optima... more Although the liver is the most common site for pancreatic islet transplantation, it is not optimal. We compared kidney, liver, muscle, and omentum as transplantation sites with regard to operative feasibility, and the efficiency of implantation and glycemic control. Islets from C57BL/6 mice were transplanted into diabetic syngeneic recipients. The mean operative time and mortality were measured to assess feasibility. To assess implantation efficiency, the marginal mass required to cure diabetes and the mean time taken to achieve normoglycemia were measured. A glucose tolerance test was performed to assess glycemic control efficiency. The data are listed in the order of the kidney, liver, muscle, and omentum, respectively. The mean mortality rate was 6.7, 20.0, 7.1, and 12.5%; the mean operative time was 10.2, 27.4, 11.2, and 19.8 min; the marginal islet mass was 100, 600, 600, and 200 islet equivalence units and the mean time to reach euglycemia was 3.0, 15.1, 26.6, and 13.9 days. T...
Continuous efforts have been made by the organ donation and transplantation community in Korea to... more Continuous efforts have been made by the organ donation and transplantation community in Korea to increase organ donation by the deceased. The authors detailed trends of organ donation and utilization over the past 10 yr using data provided by the KONOS. The yearly number of deceased donors has grown gradually since 2003. The number and percentage of old donors (> or = 50 yr) and donors dying from intracranial hemorrhage has increased continuously. Therefore, the percentage of standard criteria donors (SCD) has been declining significantly, from 94% in 2000 to 79.2% in 2009. The number of organs transplanted per donor (OTPD) has also declined slightly since 2007, from 3.28 in 2007 to 2.95 in 2009. This decline may be attributable to increases in the number and percentage of extended criteria donors (ECD) and donors after cardiac death (DCD), since the OTPD was 2.25 for DCD, 2.5 for ECD, and 3.09 for SCD in 2009. In summary, the makeup of donors has changed significantly. There is...
Tailoring of semiconducting metal oxide nanostructures, which possess controlled pore size and co... more Tailoring of semiconducting metal oxide nanostructures, which possess controlled pore size and concentration, is of great value to accurately detect various volatile organic compounds in exhaled breath, which act as potential biomarkers for many health conditions. In this work, we have developed a very simple and robust route for controlling both the size and distribution of spherical pores in electrospun WO3 nanofibers (NFs) via a sacrificial templating route using polystyrene colloids with different diameters (200 nm and 500 nm). A tentacle-like structure with randomly distributed pores on the surface of electrospun WO3 NFs were achieved, which exhibited improved surface area as well as porosity. Porous WO3 NFs with enhanced surface area exhibited high gas response (Rair/Rgas = 43.1 at 5 ppm) towards small and light H2S molecules. In contrast, porous WO3 NFs with maximized pore diameter showed a high response (Rair/Rgas = 2.8 at 5 ppm) towards large and heavy acetone molecules. Further enhanced sensing performance (Rair/Rgas = 65.6 at 5 ppm H2S) was achieved by functionalizing porous WO3 NFs with 0.1 wt% non-oxidized graphene (NOGR) flakes by forming a Schottky barrier (ΔΦ = 0.11) at the junction between the WO3 NFs (Φ = 4.56 eV) and NOGR flakes (Φ = 4.67 eV), which showed high potential for the diagnosis of halitosis.
Ž. Ž. Ž. Multiseeding with 100 r 100 grain junctions of top-seeded melt growth TSMG processed YBC... more Ž. Ž. Ž. Multiseeding with 100 r 100 grain junctions of top-seeded melt growth TSMG processed YBCO superconductors was studied. Multiple seeding shortened the processing time for the fabrication of TSMG-processed YBCO superconductors. The relationship among the number of seeds, the levitation forces and the trapped magnetic fields of the TSMG-processed Ž. Ž. YBCO samples is reported. The characteristic of the 100 r 100 grain junction is discussed in terms of a wetting angle of a melt.
The effects of the distance d between two Sm Ba Cu O seeds on the characteristics of the 100 r 10... more The effects of the distance d between two Sm Ba Cu O seeds on the characteristics of the 100 r 100 junctions 1.8 2.4 3.4 x Ž. of top-seeded melt growth TSMG processed YBCO superconductors were investigated. The trapped magnetic field at the grain junction and the levitation force of the top surface decreased with increasing d value. The degradation of the Ž. properties was discussed in terms of the presence of the residual melt-forming phases CuO and BaCuO at the grain 2 junction.
Ž. Ž. The growth nature of YBa Cu O Y123 grains at the top surfaces of top-seeded melt growth TSM... more Ž. Ž. The growth nature of YBa Cu O Y123 grains at the top surfaces of top-seeded melt growth TSMG processed 2 3 7 yy YBCO superconductors was studied in respect to the dimension of Sm Ba Cu O seeds. The top surface growth mode 1.8 2.4 3.4 x was significantly dependent on the dimensions of the seed, especially on the seed thickness. The use of thin slab-like Sm-seeds led to the nucleation of undesirable subsidiary Y123 grains at the seeded area, while such subsidiary nucleation was hardly observed when thick seeds were used. The formation mechanism of the subsidiary Y123 grains, and the effects on the levitation forces and trapped magnetic field are discussed.
Abdominal aortic aneurysms in neonates and infants are rare and are usually associated with infec... more Abdominal aortic aneurysms in neonates and infants are rare and are usually associated with infection, vasculitis, connective tissue disorder, or iatrogenic trauma such as umbilical catheterization. An idiopathic congenital abdominal aortic aneurysm is the least common category and there are few descriptions of the imaging features. We present the antenatal and postnatal imaging findings of an idiopathic congenital abdominal aortic aneurysm including the findings on US, MRI and CT.
Ex situ electrokinetic (EK) bioremediation of a laboratory-prepared pentadecane-contaminated kaol... more Ex situ electrokinetic (EK) bioremediation of a laboratory-prepared pentadecane-contaminated kaolinite was carried out. Extraneous bacteria and ionic nutrients were continuously supplied to the soil specimen by a new electrolyte circulation method, which controlled electrical pH change of electrolyte solution to keep bacterial activity. During the EK bioremediation the anode region showed the highest colony forming unit (CFU) due to electrical attraction between anode and bacteria. Simultaneous increases of CFU and uniform pentadecane removal in most soil regions demonstrated that electro-osmosis as well as electrophoresis affected the bacterial transport in soil. At 3.13 mA/cm2, increase in soil temperature to above 45 degrees C inhibited bacterial activity, which caused the decrease of removal efficiency. The removal amount of pentadecane increased with initial pentadecane concentration at the same current densities (0.63 and 1.88 mA/cm2) because of the increased amount of weakly bound pentadecane onto the soil surface. The highest removal efficiency (77.6%) was obtained at 0.63 mA/cm2 for 1000 mg/kg pentadecane after 14 days. Consequently, the present methods of EK bioremediation demonstrated superiority over the conventional bioremediation, which had inherent demerits of slow degradation and low removal efficiency.
We report a case of cerebral lipiodol embolism after transarterial chemoembolization of hepatocel... more We report a case of cerebral lipiodol embolism after transarterial chemoembolization of hepatocellular carcinoma, which was confirmed by dual-energy computed tomography (CT). A 44-year-old male patient developed left leg weakness after transarterial chemoembolization for hepatocellular carcinoma. The noncontrast CT scan of his brain revealed multiple high-attenuating lesions scattered along the gyral surface of the both cerebral hemispheres; meanwhile, the lesions disappeared on the iodine-removed virtual noncontrast images generated from dual-energy CT.
Two cases of contrast media extravasation of a ruptured aneurysm during computed tomography angio... more Two cases of contrast media extravasation of a ruptured aneurysm during computed tomography angiography (CTA) are described. The contrast media extravasation appeared as a highly attenuated twisted ribbon-like structure originating from the aneurysmal dome, and this mimicked a vascular structure. Because rebleeding of an aneurysm is accompanied by disastrous consequences, it is important to understand the imaging feature of active bleeding on CTA.
IEEE Transactions on Appiled Superconductivity, 2001
... Overpowering Quenches Hyo-Sang Choi, Hye-Rim Kim, Ok-Bae Hyun and Sang-Joon Kim ... X-ray dif... more ... Overpowering Quenches Hyo-Sang Choi, Hye-Rim Kim, Ok-Bae Hyun and Sang-Joon Kim ... X-ray diffraction and Rutherford backscattering spectroscopy data did not change considerably after repeated quenches but some minor change appeared. ...
Microchimerism is a state in which a low percentage (Ͻ 1%) of hematopoietic cells from donor orig... more Microchimerism is a state in which a low percentage (Ͻ 1%) of hematopoietic cells from donor origin persists in the recipient after solid organ transplantation or transfusion. We have developed a highly specific method using nested PCR-SSCP (single strand conformation polymorphism) analysis. Methods: We created an artificial microchimerism ranging from 1% to 0.00001% using DNA samples of UCLA DNA Exchange Program with known HLA-DRB1 allelic types. For nested PCR, generic amplification of the exon 2 of HLA DRB1/3/4/5 gene was carried out, followed by DRB1 group specific PCR (DR1ϳDR16) using a 1:200 dilution of the first PCR product. Presence of specific DRB1 alleles was detected by SSCP analysis of denatured (single stranded) 2nd PCR product. Results: Detection of microchimerism at the level of Յ0.01% was possible for all of the 25 HLA-DRB1 alleles tested using nested PCR-SSCP method, and detection sensitivity was Յ0.001% for several alleles tested. Conclusions: Nested PCR-SSCP is a highly specific and reasonably sensitive method for the detection of HLA-DRB1 microchimerism.
The majority of newly acquired nonhuman primates encounter serious problems adapting themselves t... more The majority of newly acquired nonhuman primates encounter serious problems adapting themselves to new environments or facilities. In particular, loss of appetite and abnormal behavior can occur in response to environmental stresses. These adaptation abnormalities can ultimately have an affect on the animal's growth and well-being. In this study, we evaluated the affects of a puzzle feeder on the food intake and abnormal behavior of newly acquired rhesus monkeys for a short period. The puzzle feeder was applied to 47to 58-month-old animals that had never previously encountered one. We found that there was no difference in the change of food intake between the bucket condition and the puzzle feeder condition. In contrast, the time spent for consumption of food was three times longer in the puzzle feeder condition than in the bucket condition. Two monkeys initially exhibited stereotypic behavior. One showed a decreasing, and the other an increasing pattern of abnormal behavior after introduction of the puzzle feeder. In conclusion, this result suggests that over a short period, the puzzle feeder can only affect the time for food consumption since it failed to affect the food intake and did not consistently influence stereotypic behaviors in newly acquired rhesus monkeys.
Removal characteristics of polycyclic aromatic hydrocarbons (PAHs) from low-permeable soil using ... more Removal characteristics of polycyclic aromatic hydrocarbons (PAHs) from low-permeable soil using a surfactant-enhanced electrokinetic (EK) process were investigated. Phenanthrene and kaolinite were selected as a representative PAH and a model soil. A ...
... value more rapidly than at 100 V, because the migrational flux of ions was in proportion to e... more ... value more rapidly than at 100 V, because the migrational flux of ions was in proportion to electrical potential gradient or cell voltage (Acar and Alshawabkeh, 1993). ... 3, the apparent conductivity was calculated from the change of current across the electrodes (Hamed et al., 1991 ...
An alternative distributional assumption is proposed for the stochastic volatility model. This re... more An alternative distributional assumption is proposed for the stochastic volatility model. This results in extremely flexible tail behaviour of the sampling distribudon for the observables, as well as in the availability of a simple Markov Chain Monte Carlo strategy for posterior analysis. By allowing the tail behaviour to be determined by a separate parameter, we reserve the parameters of the volatility process to dictate the degree of volatility clustering. Treatment of a leverage effect and a mean function are formally integrated in the analysis. Some empirical examples on both stock prices and exchange rates clearly indicate the presence of fat tails, in combination with high levels of volatility clustering. In addition, we find that prefiltering the data through imposing a particular mean function can be quite hazardous for inference on volatilities. Acknowledgements: The author acknowledges the hospitality of CORE where part of this work was done. Comments from Carmen Femández, Theo Nijman and Jacek Osiewalski proved very helpful. The usual disclaimer applies.
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Papers by Sangjoon Kim