• Journal of the Korean GEO-environmental Society
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• v.17 no.11
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• pp.5-14
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• 2016

The main objective of this study was to evaluate the removal properties of Cu from existing exfoliated vermiculite (EV) coated with a mixed solution of sulfuric acid and glycerol on the $580^{\circ}C$ in heating, which uses coated with glycerol of copper ions can be removed more effectively. Serial batch kinetic tests and batch sorption tests were conducted to determine the removal characteristics for Cu in aqueous solution. The result of batch kinetic test shows that removal rate, $K_{obs}$ (1/hr), of Cu are 0.579, 0.878, 3.459, and 6.578 for MEV weight 1 g (25 g/L), 2 g (50 g/L), 3 g (75 g/L), 4 g (100 g/L), respectively. In this case the initial pH of the solution was 3.26. The removal experiment according to the concentration, $K_{obs}$ (1/hr), of Cu are 1.96, 0.878, 1.25, and 1.04 for the initial concentration of 3 mg/L, 5 mg/L, 8 mg/L, 10 mg/L, and the initial pH of the solution are 3.46, 3.26, 3.10, 2.96, respectively. Influence of initial pHs on Cu removal were tested under 1g of MEV with 5 mg/L of Cu solution. $K_{obs}$ (1/hr) were increased from 0.263 (pH 3) to 0.525 (pH 5). It leads to the conclusion that the removal rates are inversely proportional to the initial Cu concentration and are increased proportional to the initial pHs. Sorption capacity of MEV was determined by batch sorption tests. The maximum sorption capacity ($Q_{max}$) obtained from Langmuir was 0.761 mg/g, Linear and Freundlich partition coefficients were 0.494 L/g and 0.729 L/g (1/n = 0.476). These results show that the MEV could be used as an excellent adsorbent for copper contained in various types of aqueous solutions.

• Tuberculosis and Respiratory Diseases
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• v.41 no.3
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• pp.270-276
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• 1994

Background: The measurement of nonspecific bronchial hyperreactivity is valuable for diagnosis and management of bronchial asthma. Methacholine or histamine is used for the pharmacologic provocation test. Usually a methacholine bronchial provocation test is performed by a dosing technique with counted number of breaths. A dosimeter is indispensable in the dosing technique. Recently a timed tidal breathing technique which dose not need an expensive dosimeter was introduced. We measured the degree of nonspecific bronchial hyperreactivity to histamine using a simple timed tidal breathing technique. Method: Forty two healthy volunteers, 12 patients with bronchial asthma(BA), 10 patients with rhinitis(RH) and 10 patients with upper respiratory infection(URI) participated in the study. The subject's nose was clipped and inhalation continued during tidal breathing for 2 minutes via a face mask. $FEV_1$ was measured at 30 seconds, 90 seconds after inhalation and inhalation of next solution was continued until there was a fall in $FEV_1$ of 20%. Histamine PC20 was defined as the concentration at 20% fall of $FEV_1$ and it was obtained from the log dose-response curve by linear interpolation. Results: Inhalation of serial dilution of histamine could be performed in all patients without significant side effects. The geometric mean${\pm}$standard deviation of histamine PC20 in healthy volunteers is $8.27{\pm}2.22mg/ml$, BA group $0.33{\pm}3.02mg/ml$, RH group $0.85{\pm}3.24mg/ml$, and URI group $1.47{\pm}1.98mg/ml$. Conclusion: Histamine bronchial provocation test using timed tidal breath method is a simple and suitable tool for management of patients with bronchial hyperreactivity.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.9
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• pp.793-802
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• 2009

Adsorption properties were estimated for the organic silicon compounds (siloxanes) in an actual landfill gas (LFG) using adsorbents such as coconut activated carbon, coal activated carbon, silica gel, sulfur adsorbent, carbonized sludge, and molecular sieve 13X. Coconut activated carbon showed the highest removal efficiency of more than 95%. The desorption of hexamethyldisiloxane (L2) from the adsorbent, however, resulted in the remarkable concentration variation of the compound in the treated gas. Silica gel, which had high adsorption capacity for L2 in single substance adsorption experiment in the other study, could not remove the component in the actual landfill gas while it adsorbed well octamethylcyclotetrasiloxane (D4) and decamethylcyclopentasiloxane (D5) in the LFG. Therefore the elimination of hexamethyldisiloxane is an important factor to determine the level of total organosilicon compound in pretreated landfill gas. Moreover, the L2 from the actual landfill gas was effectively adsorbed by the serial adsorption test using two columns packed with coconut activated carbon which has the great capacity of siloxanes removal among others. In order to utilize efficiently LFG as a renewable energy, the emission and adsorptive characteristics of the substance to be treated should be considered for the organization, operation, and management of pretreatment process.

• The Journal of Korean Academy of Prosthodontics
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• v.45 no.2
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• pp.263-273
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• 2007

Statement of problem: Alteration of tooth function is assumed to be changed by stress/strain on the adjacent alveolar bone, producing changes in morphology similar to those described for other load-bearing bones. When teeth are removed, opposing teeth will not be functioned. When edentulous area is restored by implant prostheses, opposing teeth will be received physiologic mechanical stimuli. Purpose: The aim of this study was to evaluate the bone changes around the teeth opposing implant restoration installed mandibular posterior area. Material and method: Eight patients who had mandibular posterior edentulous area were treated with implants. Radiographs of the opposing teeth were taken at implant prostheses delivery(baseline), 3 months, and 6 months later. Customized film holding device was fabricated to standardize the projection geometry for serial radiographs of opposing teeth. Direct digital image was obtained. Gray values of region of interest at each digital image were measured and compared according to time lapse. Repeated measured analysis of variance and post-hoc Scheffe's test were performed at the 95% significance level. Results: Alveolar bone changes around the natural teeth opposing the posterior implant in mandible showed statistically significant difference compared to control group(P<0.05). And gray values of alveolar bone around the teeth opposing implants were increased. There were no statistically significant differences of alveolar bone changes between crestal group and middle group and between mesial group and distal group according to time lapse(P>0.05). There were no statistically significant differences of alveolar bone changes among mesial-crestal group, mesial-middle group, distal-crestal group, distal-middle group, and control group(P>0.05). Conclusion: Alveolar bone around the natural teeth opposing the implant prosthesis showed gradual bony apposition.

• Journal of the korean academy of Pediatric Dentistry
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• v.38 no.2
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• pp.161-169
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• 2011

Longitudinal serial cephalometric films in the every second year from fifty girls were used for the analysis of growth pattern of maxillary alveolar bone (MAE). Six parameters regarding MAB height were measured and were compared with stature and chronological age. Descriptive analysis. correlation coefficient test and linear regression analysis were done for the statistical analyses. 1. The height of MAE increased until 14 years although growth velocity was gradually decreased. which was different with stature growth pattern. 2. The correlation coefficients between chronological age and MAB height were high and had no statistical differences with those of stature and MAB height. In addition. the correlation coefficients between chronological age groups within each parameter of MAB were very high. 3. The growth amount of MAB could be predicted using linear regression analysis on the basis of chronological age data. The growth pattern between MAE and statue was quite different because of the growth pattern difference between skeletal and neuronal system. Therefore. growth pattern of Korean MAB must be considered in dental treatment of youth. Also. close relationship between chronological age and MAB height would be useful when clinicians want to predict growth amount of MAE for the dental implant treatment.

• Development and Reproduction
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• v.9 no.2
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• pp.135-142
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• 2005

Vitellogenins(VTGs) are the precursor of egg-yolk proteins in most oviparous species from invertebrates to vertebrates. In oviparose vertebrates, VTGs are synthesized in the liver and transported through the blood to oocytes. In female fish, concentrations of plasma VTG increase rapidly at onset of vitellogenesis in the normal reproductive cycle. Male fishes also possess the gene for VTG, but plasma concentrations of the protein typically remain small, presumably due to low levels of endogenous estrogens. However, exposure of males to exogenous estrogenic mimics can result elevated. Therefore, the VTG in fish can be used as a useful biomarker for appropriate tools of endocrine disrupting compounds effects. In this studies, we prepared the test methods that can measure the plasma VTG level in the gobies that live in polluted area with mimic estrogen. For the purpose, we purified VTG of floating goby(Chaenogobius annularis) and prepared specific monoclonal and polyclonal antisera to yolk protein, then developed a sandwich competitive ELISA system for measurement of plasma VTG levels. Validation for the ELISA system using monoclonal and polyclonal antibodies against VTG was tested. The absorbance curve of serial dilutions of serum from vitellogenic female was paralleled to the standard curve of VTG, but normal male was not paralleled. The developed sandwich ELISA system was measured for VTG levels in plasma of common goby(Acanthogobius flaviman) and javeline goby(A. hasta) as well as in plasma of floating goby(C. annularis).

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.2430-2434
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• 2005

Automatic FPC punching instrument for the improvement of working condition and cost saving is introduced in this paper. FPC(flexible printed circuit) is used to detect the contact position of K/B and button like a cellular phone. Depending on the quality of the printed ink and position of reference punching point to the FPC, the resistance and current are varied to the malfunctioning values. The size of reference punching point is 2mm and the above. Because the punching operation is done manually, the accuracy of the punching degree is varied with operator's condition. Recently, The punching accuracy has deteriorated severely to the 2mm punching reference hall so that assembly of the K/B has hardly done. To improve this manual punching operation to the FPC, automatic FPC punching system is introduced. Precise mechanical parts like a 5-step stepping motor and ball screw mechanism are designed and tested and low cost PC camera is used for the sake of cost down instead of using high quality vision systems for the FA. 3D Mechanical design tool(Pro/E) is used to manage the exact tolerance circumstances and avoid design failures. Simulation is performed to make the complete vision based punching machine before assembly, and this procedure led to the manufacturing cost saving. As the image processing algorithms, dilation, erosion, and threshold calculation is applied to obtain an exact center position from the FPC print marks. These image processing algorithms made the original images having various noises have clean binary pixels which is easy to calculate the center position of print marks. Moment and Least square method are used to calculate the center position of objects. In this development circumstance, Moment method was superior to the Least square one at the calculation of speed and against noise. Main control panel is programmed by Visual C++ and graphical Active X for the whole management of vision based automatic punching machine. Operating modes like manual, calibration, and automatic mode are added to the main control panel for the compensation of bad FPC print conditions and mechanical tolerance occurring in the case of punch and die reassembly. Test algorithms and programs showed good results to the designed automatic punching system and led to the increase of productivity and huge cost down to law material like FPC by avoiding bad quality.

• Spatial Information Research
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• v.22 no.1
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• pp.35-43
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• 2014

The Triangle Mesh Warping method is suggested and applied in coordinate transformation to world geodetic system in this study. The common points of Uiwang city are used to compare the transformation accuracy of the suggested methods with existing national coordinate transformation methods. As a result, the Triangle Mesh Warping method was satisfied with accuracy criteria for positioning on a map larger than scale 1/1,000 with smaller number of common points and without distortion modeling. Additionally, in case of Guri and Pyeongtaek city that established the World Geodetic System, the suggested method generates the result of transformation accuracy better than 5cm. Based on the test, it was found that the suggested method improves the problem of securing many common points and reduces the problem of mis-match between the transformed data of adjacent areas. Accordingly, for transformation of large-scale topographic map, cadastral map, GIS DB and serial cadastral map to the World Geodetic System, it is judged that the Triangle Mesh Warping would be a good method for economical efficiency and accuracy using by minimum common point.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.25 no.3
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• pp.21-30
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• 1980

This is the fourth report in serial studies on the botanical characters of Korean maize lines collected. Several plant characters and genetical nature of lines were investigated and compared among selfed, sibbed and test crossed lines. Inbreeding depression and heterosis, and homozygosity expressed in percent were calculated. Throughout the study a great extent of variation of plant characters and genetical variation expressed in terms of inbreeding depression and heterosis were observed. The observed plant and genetic variation of plant characters were assumed to be enough for providing new breeding materials for future maize breeding program. The degree of homozygosity of Korean local maize lines suggested that a great portion of maize grown by Korean farmers presently are near or close to inbred and presumed to show a great heterosis when crossed to divergent lines.

• International Journal of Industrial Entomology and Biomaterials
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• v.4 no.2
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• pp.93-100
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• 2002

Cocoon production, which is a representative of traditional sericulture shifted into silkworm powder production in the spring of 1995. This, infect, signifies the change from the dress-centered textile business to the bio-industry and the functional resource industry. One of the most outstanding shifting is utilization of silkworm larvae for anti-diabetic agent. In Asian countries including Korea, silkworm powder derived from the domestic silkworm (Bombyx mori L.) has long been favored for anti-diabetic agent, but its efficacy was not tested until last decade by modern scientific methods. In this article, we reviewed the major researches on the silkworm powder as a blood glucose-lowering substance. After the beginning test of the efficacy of silkworm powder by a cooperative research between Department of Sericulture and Entomlogy, NIAST, RDA and Kyung Hee University, substantial data have been accumulated so far, In a serial experiment to select best condition, the fifth instar larvae prepared by freeze dry method turned out to have the best blood glucose-lowering effect. In the pharmacological experiment to understand the mechanism of silkworm powder in small intestine, the silkworm powder turned out to inhibit the activity of ${\alpha}$-glucosidase, by competitively binding to $\alpha$-type disaccharides. The animal experiment showed that the extract of silkworm powder prevents a rapid increase of blood glucose level after meal and prevents hunger and law blood glucose level during empty stomach. In the experiment to isolate the major component of silkworm powder, which exerts blood glucose-lowering effect, 1-deoxynojirimy-cin (DNJ) was eventually mass-purified, and it turned out that DNJ isolated from silkworm powder was excellent in its blood glucose-lowering effect. In the experiment to understand the personal difference of the efficacy of the silkworm powder, clinical candidates were divided on the basis of the criterion of traditional Chinese medicine: Tae-Yang, Tae-Um, So-yang, and So-Um. The result showed that silkworm powder has a tendency to reduce blood glucose level at fasting and at 2 hours after meal, and this trend was somewhat obvious in the Tae-Um body type. In summary, we reviewed scientific papers on the efficacy of silkworm powder and its purified DNJ as a blood glucose-lowering agent. These suggest that silkworm powder truly possesses blood glucose-lowering effect as documented in the traditional Chinese medicine, although further researches will be required to develop them as "medical" resource instead of functional food.