• Korean Journal of Environmental Agriculture
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• v.26 no.3
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• pp.210-216
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• 2007

The cadmium (Cd) and zinc (Zn) contamination of soils and cultivated crop plants by zinc smelting activities was studied. In the study area of the vicinity of ${\triangle}{\triangle}$ zinc smelting factory in Korea, soils and corn plants were sampled at corn harvesting stage and analyzed Cd and Zn concentration as well as Cd and Zn fraction and chemical properties in soils. At 600 m radius of studied area, Cd and Zn were highly accumulated in the surface soils (0 - 20 cm) showed greater than the Korean warning criteria (Cd 1.5, Zn 300 mg $kg^{-1}$) with corresponding values 1.7 and 407 mg $kg^{-1}$, respectively. The leaf part gave higher Cd concentration with the corresponding value of 9.5 mg $kg^{-1}$ as compared to the stem and grains pare (1.6 and 0.18 mg $kg^{-1}$), respectively. Higher Zn concentration was also obtained from the leaf part of the corn plant which gave the value of 1,733 mg $kg^{-1}$. The stem and grain part gave corresponding values of 547 and 61 mg $kg^{-1}$. The order of the mean Cd concentration in fractions is F3 (oxidizable fraction) > F2 (reducible fraction) > F4 (residual fraction) > F1 (exchangeable + acidic fraction). A highly positive correlation is observed between F2 and concentration of Cd and Zn in both plant pare, leaf and grain. Highly positive correlations are shown in the pH exchangeable Ca and Mg, and CEC when correlated with Cd and Zn bound to F4 fractions. To reduce Cd and Zn uptake by corn plant in an arable land heavily contaminated with Cd and Zn as affected by smelting factory, an efficient and effective soil management to increase soil pH and CEC is thus recommended.

• Journal of the Korean Electrochemical Society
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• v.3 no.3
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• pp.162-168
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• 2000

The influence of phenolsulfunate concentrations on electroplating characteristics and electrochemical behaviors was investigated with a viewpoint of electrolyte aging using the circulation cell and potentiostate And comparison of tinplate coating appearance such as glossiness and Image clarify has been also studied with varying of phenolsulfonic acid (PSA) solutions. As the aging of electrolyte proceeded, the limiting current density was moved to a lower current density region by the limitation of mass transfer, and higher phenolsulfunate concentrations resulted in the narrower optimum current density range and deterioration of coating surface of tinplates. The difference of the limiting current density was not remarkable with increasing electrolyte temperature. Thus the electrolyte aging was attributed to the limitation of thermally-activated process such as mass transfer of reducible ions. It has also been considered that the accumulation of phenolsulfonate suppressed normal electrotinning reaction by reducing the mobility of stannous ions, taking into account of the smaller effect of electrolyte aging. Experiments showed similar polarization behavior between the electrolyte of high phenolsufonate solution and the aged one, which comes to conclude that the accumulation of phenolsulfonate is one of the major causes of electrolyte aging.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.18 no.1
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• pp.81-136
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• 1988

The aim of this study was to determine whether T.M.J. tomographic examination yielded significant differences in condyle positions among asymptomatic, myalgia, derangement, and arthrosis groups of T.M.J. disorders. The author obtained sagittal linear tomograms of right and left T.M.Js. of 36 asymptomatic, 22 myalgia, 54 derangement, and 31 arthrosis patients taken at serial lateral, central, and medial sections in the intercuspal position after submentovertex radiographs analyzed. With the dual linear measurements of the posterior and anterior interarticular space, condyle positions were mathematically expressed as proportion. All data from these analysis was recorded and processed statistically. The results were obtained as follows. 1. In asymptomatic group, radiographically concentric condyle position was found in 50.0% to 65.4% of subjects, with a substantial range of variability. No significant differences existed between men and women and also between right and left T.M.Js. for condyle position. 2. In women, significant difference for mean condyle position of left lateral section of each diagnostic category existed between derangement and myalgia groups (P<.05). Also that of left central section existed between derangement and myalgia groups, and that of left medial section existed between derangement and myalgia groups (P<.05). 3. In main-symptom side, condyle position in myalgia group was more concentric, and condyle position in derangement group was more posterior. This showed significant differences between derangement and myalgia groups in lateral, central, and medial sections of main- symptom sides, and only between derangement and myalgia groups in central section of contra-lateral sides (P<.05). Condyle position in arthrosis group was broadly distributed among all positions. 4. In contra-lateral side, significant difference for mean condyle position of central section of each symptomatic group existed between derangement and myalgia groups (P<.05). Condyle position in derangement group was more posterior. The distribution of the condyle position of contra-lateral side in patients with unilateral symptoms was similar to that of main-symptom side in each symptomatic group. No significant difference existed between main-symptom and contra-lateral sides. 5. For internal derangement subgroups, condyle position in reducible disc displacement group was more posterior than non-reciprocal and locking groups, but there was no significant difference. 6. From 16 to 25 years, significant difference for mean condyle position of medial section of main-symptom side of each symptomatic group existed between myalgia and derangement groups (P<.05).

• Information Systems Review
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• v.9 no.1
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• pp.45-65
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• 2007

In medical industry, health insurance bill audit is unique and essential process in general hospitals. The health insurance bill audit process is very important because not only for hospital's profit but also hospital's reputation. Particularly, at the large general hospitals many related workers including analysts, nurses, and etc. have engaged in the health insurance bill audit process. This paper introduces a case of health insurance bill audit for finding reducible health insurance bill cases using decision tree induction techniques at a large general hospital in Korea. When supervised learning methods had been tried to be applied, one of major problems was data imbalance problem in the health insurance bill audit data. In other words, there were many normal(passing) cases and relatively small number of reduction cases in a bill audit dataset. To resolve the problem, in this study, well-known methods for imbalanced data sets including over sampling of rare cases, under sampling of major cases, and adjusting the misclassification cost are combined in several ways to find appropriate decision trees that satisfy required conditions in health insurance bill audit situation.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.246-246
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• 2012

Smart catalyst design though novel catalyst preparation methods can improve catalytic activity of transition metals on reducible oxide supports such as titania by enhancement of metal oxide interface effects. In this work, we investigated Pt nanoparticles/titania catalysts under CO oxidation reaction by using novel preparation methods in order to enhance its catalytic activity by optimizing metal oxide interface. Arc plasma deposition (APD) and metal impregnation techniques are employed to achieve Pt metal deposition on titania supports which are prepared by multi-target sputtering and Sol-gel techniques. In order to tailor metal-support interface for catalytic CO oxidation reaction, Pt nanoparticles and thin films are deposited in varying surface coverages on sputtered titania films using APD. To assess the role of oxide support at the interface, APD-Pt is deposited on sputtered and Sol-gel prepared titania films. Lastly, characteristics of APD-Pt process are compared with Pt impregnation technique. Our results show that activity of Pt nanoparticles is improved when supported over Sol-Gel prepared titania than sputtered titania film. It is suggested that this enhanced activity can be partly ascribed to a very rough titania surface with the higher free metal surface area and higher number of sites at the interface between the metal and the support. Also, APD-Pt shows superior catalytic activity under CO oxidation as compared to Pt impregnation on sputtered titania support. XPS results show that bulk oxide is formed on Pt when deposited through impregnation and has higher proportion of oxidized Pt in the form of $Pt^{2+/4+}$ oxidation states than Pt metal. APD-Pt shows, however, mild oxidation with large proportion of active Pt metal. APD-Pt also shows trend of increasing CO oxidation activity with number of shots. The activity continues to increase with surface coverage beyond 100%, thus suggesting a very rough and porous Pt films with higher active surface metal sites due to an increased surface area available for the reactant CO and $O_2$ molecules. The results suggest a novel approach for systematic investigation into metal oxide interface by rational catalysts design which can be extended to other metal-support systems in the future.

• Advances in pediatric surgery
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• v.12 no.2
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• pp.155-166
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• 2006

Inguinal hernia is the most common disease treated by the pediatric surgeon. There are several controversial aspects of management 1)the optimal timing of surgical repair, especially for preterm babies, 2)contralateral groin exploration during repair of a clinically unilateral hernia, 3)use of laparoscope in contralateral groin exploration, 4)timing of surgical repair of cord hydrocele, 5)perioperative pain control, 6)perioperative management of anemia. In this survey, we attempted to determine the approach of members of KAPS to these aspects of hernia treatment. A questionnaire by e-mail or FAX was sent to all members. The content of the questionnaire were adapted from the "American Academy of Pediatrics (AAP) Section on Surgery hernia survey revisited (J Pediatr Surg 40, 1009-1014, 2005)". For full-term male baby, most surgeons (85.7 %) perform an elective operation as soon as diagnosis was made. For reducible hernia found in ex-preterm infants already discharged from the neonatal intensive care unit (NICU), 76.2 % of surgeons performed an elective repair under general anesthesia (85.8 %). 42.9 % of the surgeons performed the repair just before discharge. For same-day surgery for the ex-premature baby, the opinion was evenly divided. For an inguinal hernia with a contralateral undescended testis in a preterm baby, 61.9 % of surgeons choose to 'wait and see' until 12 month of age. The most important consideration in deciding the timing of surgery of inguinal hernia in preterm baby was the existence of bronchopulmonary dysplasia (82.4 %), episode of apnea/bradycardia on home monitoring (70.6 %). Most surgeons do not explore the contralateral groin during unilateral hernia repair. Laparoscope has not been tried. Most surgeons do not give perioperative analgesics or blood transfusion.

• Korean Journal of Environmental Agriculture
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• v.35 no.2
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• pp.152-157
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• 2016

BACKGROUND: Since bottom ash (BA) contains considerable amounts of CaO and MgO, it could be a useful amendment to increase soil pH and to immobilize cadmium (Cd). This study was conducted to evaluate effect of BA application in reducing Cd phytoavailability.METHODS AND RESULTS: Bottom ash was applied at the rate of 0, 20, 40, and 80 Mg/ha to Cd contaminated soil, and then lettuce was cultivated under field condition. soil pH and net negative charge increased slightly with increasing BA application; however, there was no statistical difference among the rates. Water soluble, exchangeable+acidic, reducible, and oxidizable fraction of Cd decreased with increasing bottom ash application rate, whereas residual fraction of Cd increased with increasing bottom ash application rate. Lettuce yield increased with rate of bottom ash up to 40 kg/ha. Visual evidences of cadmium toxicity and growth inhibition were not found during lettuce cultivation.CONCLUSION: Bottom ash was effective to reduce phytoextractability of Cd and to increase lettuce yield. Conclusively, BA could be a good soil amendment to reduce Cd phytoavailability in contaminated arable soil.

• Korean Journal of Environmental Agriculture
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• v.32 no.1
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• pp.1-8
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• 2013

BACKGROUND: Many studies associated with cadmium (Cd) immobilization using lime fertilizer have been conducted for several decades. However, these studies did not suggest exact mechanism of Cd immobilization using lime fertilizer and evaluated effect of lime fertilizer on Cd phytoavailability in rice paddy soil under field condition. METHODS AND RESULTS: This study was conducted to determine exact mechanism of Cd immobilization using lime fertilizer and evaluate liming effect on Cd uptake of rice in contaminated paddy soil. $Ca(OH)_2$ was mixed with Cd contaminated arable soil at rates corresponding to 0, 1,000, 2,000, 4,000, and 8,000 mg/kg. The limed soil was moistened to paddy soil condition, and incubated at $25^{\circ}C$ for 4 weeks. $NH_4OAc$ extractable Cd concentration in soil decreased significantly with increasing $Ca(OH)_2$ rate, since $Ca(OH)_2$ markedly increased net negative charge of soil by pH increase, and decreased bioavailable Cd fractions (F1; exchangeable + acidic and reducible Cd fraction). Calculated solubility diagram indicated that Cd solubility was controlled by soil-Cd. $NH_4OAc$ extractable Cd and F1 concentration were negatively related to soil pH and negative charge. $Ca(OH)_2$ was applied at rates 0, 2, 4, and 8 Mg/ha and then cultivated rice in the paddy soil under field condition. Cadmium concentrations in grain, straw, and root of rice plant decreased significantly with increasing application rate of $Ca(OH)_2$. CONCLUSION(S): Alleviation of Cd phytoavailability with $Ca(OH)_2$ can be attributed primarily to Cd immobilization due to the increase in soil pH and negative charge rather than precipitation of $Cd(OH)_2$ or $CdCO_3$, and therefore, $Ca(OH)_2$ is effective for reducing Cd phytoavailability of rice in paddy soil.

• Clinical and Experimental Pediatrics
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• v.45 no.4
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• pp.466-472
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• 2002

Purpose : The diagnosis of Meckel's diverticulum is difficult and delayed because it presents with various clinical symptoms. We evaluated clinical, imaging and pathologic findings of Meckel's diverticulum to facilitate detection of Meckel's diverticulum in children. Methods : Review of clinical, imaging, surgical and pathological findings in 10 children aged 7 days to 14 years with Meckel's diverticulum during an 8-year period, 1993-2001, at Ewha Womans University Hospital was undertaken. Results : The male to female ratio was 2.3 : 1. The chief complaint was painless lower gastrointestinal( GI) bleeding; others were abdominal pain, abdominal distention and vomiting, in order of frequency. The diagonsis before surgery were Meckel's diverticulum in 5 patients, non-reducible intussusception in 3 patients and intestinal obstruction in 2 patients. The diverticulum was located between 35 cm to 70 cm proximal to the ileocecal valve. The length of the diverticulum ranged from 4 cm to 12 cm and 80% of it was within 5 cm. A Meckel scan($^{99m}Tc-pertechnetate$ scintigraphy) after cimetidine administration was done in 6 cases. All 5 cases that presented with lower GI bleeding had ectopic gastric mucosa confirmed on pathology. Out of 5 cases of ectopic gastric mucosa, only 4 cases were positive on the Meckel's scan. Conclusion : In cases of unexplained GI bleeding, obstruction, or inflammation diagnostic workup should be carried out to rule out Meckel's diverticulum. Laparoscopy, high resolution ultrasonography and computed tomography of the abdomen may be indicated in the assessment of pediatric patient with lower GI bleeding, especially in patients with suspected bleeding from Meckel's diverticulum showing negative Meckel's scan.

• Journal of Soil and Groundwater Environment
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• v.11 no.5
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• pp.20-34
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• 2006

This study was undertaken to assess the anthropogenic impact on trace metal concentrations (Zn, Cu, Pb, Cr, Ni, and Cd) of roadside sediments (N = 70) from No.7 national road within the watershed of Hoidong Reservoir in Pusan City and to estimate the potential mobility of selected metals using sequential extraction. We generally found high concentrations of metals, especially Zn, Cu and Pb, affected by anthropogenic inputs. Compared to the trace metal concentrations of uncontaminated stream sediments, arithmetic mean concentrations of roadside sediments were about 7 times higher for Cu, 4 times higher for Zn, 3 times higher for Pb and Cr and, 2 times higher for Ni and As. Speciation data on the basis of sequential extraction indicate that most of the trace metals considered do not occur in significant quantities in the exchangeable fraction, except for Cd and Ni whose exchangeable fractions are appreciable (average 29.3 and 25.8%, respectively). Other metals such as Zn (51.4%) and Pb (45.2%) are preferentially bound to the reducible fraction, and therefore they can be potentially released by a pH decrease and/or redox change. Copper is mainly found in the organic fraction, while Cd is highest in the exchangeable fraction, and Cr and Ni in the residual fraction. Considering the proportion of metals bound to the exchangeable and carbonate fractions, the comparative mobility of metals probably decreases in the order of Cd>Ni>Pb>Zn>Cr>Cu. Although the total concentration data showed that Zn was typically present in potentially harmful concentration levels, the data on metal partitioning indicated that Cd, Ni and Pb pose the highest potential hazard for runoff water. As potential changes of redox state and pH may remobilize the metals bound to carbonates, amorphous oxides, and/or organic matter, and may release and flush them through drain networks into the watershed of Hoidong Reservoir, careful monitoring of environmental conditions appears to be very important.