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Sorption Efficiency of the Bamboo Charcoal to Remove the Cesium in the Contaminated Water System (오염수계 내 세슘 제거를 위한 대나무 활성탄의 흡착효율 규명)

  • Ahn, Joungpil;Lee, Minhee
    • Economic and Environmental Geology
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    • v.51 no.2
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    • pp.87-97
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    • 2018
  • The cesium (Cs) removal from the contaminated water system has been considered to be difficult because the cesium likes to exist as soluble phases such as ion and complexes than the solid in water system. Many researches have focused on developing the breakthrough adsorbent to increase the cesium removal efficiency in water. In this study, the laboratory scale experiments were performed to investigate the feasibility of the adsorption process using the bamboo charcoal for the Cs contaminated water system. The Cs removal efficiency of the bamboo charcoal were measured and the optimal adsorption conditions were determined by the adsorption batch experiments. Total 5 types of commercialized bamboo charcoals in Korea were used to identify their surface properties from SEM-EDS and XRD analyses and 3 types of bamboo charcoals having large specific surface areas were used for the adsorption batch experiment. The batch experiments to calculate the Cs removal efficiency were performed at conditions of various Cs concentration (0.01 - 10 mg/L), pH (3 - 11), temperature ($5-30^{\circ}C$), and adsorption time (10 - 120 min.). Experimental results were fitted to the Langmuir adsorption isotherm curve and their adsorption constants were determined to understand the adsorption properties of bamboo charcoal for Cs contaminated water system. From results of SEM-EDS analyses, the surfaces of bamboo charcoal particles were composed of typical fiber structures having various pores and dense lamella structures in supporting major adsorption spaces for Cs. From results of adsorption batch experiments, the Cs-133 removal efficiency of C type bamboo charcoal was the highest among those of 3 bamboo charcoal types and it was higher than 75 % (maximum of 82 %) even when the initial Cs concentration in water was lower than 1.0 mg/L, suggesting that the adsorption process using the bamboo charcoal has a great potential to remove Cs from the genuine Cs contaminated water, of which Cs concentration is low (< 1.0 mg/L) in general. The high Cs removal efficiency of bamboo charcoal was maintained in a relatively wide range of temperatures and pHs, supporting that the usage of the bamboo charcoal is feasible for various types of water. Experimental results were similar to the Langmuir adsorption model and the maximum amount of Cs adsorption (qm:mg/g) was 63.4 mg/g, which was higher than those of commercialized adsorbents used in previous studies. The surface coverage (${\theta}$) of bamboo charcoal was also maintained in low when the Cs concentration in water was < 1.0 mg/L, investigating that the Cs contaminated water can be remediated up with a small amount of bamboo charcoal.

Comparision of PCR-RFLP, PCR-SSCP, Amplication Refractory Mutation System(ARMS) in Leu72Met Polymorphism of Ghrelin Gene (Ghrelin 유전자의 Leu72Met 다형성 분석에서 PCR-RFLP, PCR-SSCP, Amplication Refractory Mutation System(ARMS)의 비교분석)

  • Kang, Ju Sung;Kim, Se Rim;Kim, Sun Young;Joo, Chan Uhng;Cho, Soo Chul;Hwang, Pyoung Han
    • Clinical and Experimental Pediatrics
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    • v.48 no.10
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    • pp.1068-1075
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    • 2005
  • Purpose : The role of ghrelin, which promotes the secretion of growth hormone, was not well known until now. Recently it was found that the mutation of ghrelin gene is related to obesity and diabetes. This study is to find the screening method that can easily and effectively detect the polymorphism of Leu72Met in ghrelin gene of obesity patients and apply it to clinical usage. Methods : We compared PCR-RFLP, PCR-SSCP and ARMS methodologies for analyzing of the polymorphism of Leu72Met in ghrelin gene of obesity children, and also studied the merits and demerits of these methodologies. Results : In this study, we were able to find out the band of peculiar allele of Leu72Met in ghrelin gene using PCR-RFLP, PCR-SSCP and ARMS analyses. The polymorphism of Leu72Met in ghrelin gene determined by all above methodologies was in complete agreement. Compared to the PCR-RFLP and PCR-SSCP, ARMS analysis is simple, inexpensive and also consume less time. It is very sensitive to analyze the polymorphism and easy to understand the results of test. Conclusion : Though PCR-RFLP, PCR-SSCP and ARMS analyses were sensitive to analyze the polymorphism of Leu72Met in ghrelin gene, ARMS analysis appears to be more efficient than PCR-RFLP and PCR-SSCP. Therefore, we conclude that ARMS analysis is suitable to analyze the polymorphism of Leu72Met in ghrelin gene for large quantity of specimens.

Estimation of the Possible Age for Using Various Types of Inhaler by In-Check Inspiratory Flow Meter(TM) (In-Check Inspiratory Flow Meter(TM)를 사용하여 추정한 다양한 흡입기구의 사용 가능한 연령)

  • Jung, Kyung Hyun;Kim, Sun Ye;Lee, Jun Ho;Kim, Kye Sung;Jang, Yook;Han, Man Yong
    • Clinical and Experimental Pediatrics
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    • v.45 no.2
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    • pp.192-198
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    • 2002
  • Purpose : It is important to select and use kinds of Inhaler appropriate to the age of the patient and severity of symptoms. Several kinds of Inhaler have been developed and recommended according to each inhaler's resistance and usage method. We evaluated the usable age of 4 inhalers (turbulent flow inhalers, multi unit dose inhalers, breath actuated MDI, and autohalers) by measuring peak inspiratory flow(PIF) using $In-Check^{(TM)}$ Inspiratory Flow Meter. Methods : Ninety three patients aged from 3 to 7 years(mean $57{\pm}12.9$ mo.) who had admitted to CHA hospital from July 2000 to April 2001 were enrolled. Study patients were divided into 4 groups according to age : 3-4 years of age(group A, n=31), 4-5 years of age(group B, n=32), 5-6 years of age(group C, n=18), and 6-7 years of age(group D, n=12). Results : Out of total 93 patients, 23(71%), 27(84%), 17(94%) patients of each group A, B, C and all 12 patients of group D could use the 4 types of inhaler through adequated education. In all four groups, height, body weight and age were significantly correlated(P<0.05). Usable age, height and weight of children who can use turbulent flow inhaler(TFI) were each 8 year 7 month old, 144 cm, 32.0 kg, and those of multi unit dose inhaler(MUD) were 2 year 10 month old, 92 cm, 12.0 kg. Also that of breath-actuated MDI were 1 yr 8 months, 83 cm, 8.5 kg and that of autohaler were 2 yr 8 months, 91 cm, 11.0 kg Conclusion : We concluded that the ability to use inhalers correlated with height, weight and age of the patients. Multi unit dose inhalers, Breath actuated MDI and Autohaler are useful after 3 years of age through adequate education.

Inexpensive Visual Motion Data Glove for Human-Computer Interface Via Hand Gesture Recognition (손 동작 인식을 통한 인간 - 컴퓨터 인터페이스용 저가형 비주얼 모션 데이터 글러브)

  • Han, Young-Mo
    • The KIPS Transactions:PartB
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    • v.16B no.5
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    • pp.341-346
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    • 2009
  • The motion data glove is a representative human-computer interaction tool that inputs human hand gestures to computers by measuring their motions. The motion data glove is essential equipment used for new computer technologiesincluding home automation, virtual reality, biometrics, motion capture. For its popular usage, this paper attempts to develop an inexpensive visual.type motion data glove that can be used without any special equipment. The proposed approach has the special feature; it can be developed as a low-cost one becauseof not using high-cost motion-sensing fibers that were used in the conventional approaches. That makes its easy production and popular use possible. This approach adopts a visual method that is obtained by improving conventional optic motion capture technology, instead of mechanical method using motion-sensing fibers. Compared to conventional visual methods, the proposed method has the following advantages and originalities Firstly, conventional visual methods use many cameras and equipments to reconstruct 3D pose with eliminating occlusions But the proposed method adopts a mono vision approachthat makes simple and low cost equipments possible. Secondly, conventional mono vision methods have difficulty in reconstructing 3D pose of occluded parts in images because they have weak points about occlusions. But the proposed approach can reconstruct occluded parts in images by using originally designed thin-bar-shaped optic indicators. Thirdly, many cases of conventional methods use nonlinear numerical computation image analysis algorithm, so they have inconvenience about their initialization and computation times. But the proposed method improves these inconveniences by using a closed-form image analysis algorithm that is obtained from original formulation. Fourthly, many cases of conventional closed-form algorithms use approximations in their formulations processes, so they have disadvantages of low accuracy and confined applications due to singularities. But the proposed method improves these disadvantages by original formulation techniques where a closed-form algorithm is derived by using exponential-form twist coordinates, instead of using approximations or local parameterizations such as Euler angels.

Enzymatic Synthesis of Flame Retardant Phenolic Polymers Catalyzed by Horseradish Peroxidase (Horseradish Peroxidase 효소촉매에 의한 난연성 페놀고분자의 합성)

  • Park, Han Sol;Park, Jung Hee;Lee, Hak Sung;Ryu, Keungarp
    • Korean Chemical Engineering Research
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    • v.51 no.1
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    • pp.111-115
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    • 2013
  • The optimum synthetic conditions of poly(p-phenylphenol) by horseradish peroxidase in dioxane:water (80:20 v/v) mixtures were studied. The stability against thermal degradation and structural properties of the synthesized phenolic resins were investigated by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC), respectively. The synthetic yield of poly(p-phenylphenol) increased upon the increase of the amount of enzyme up to 0.25 mg HRP/mL, then leveled off for further increase of the enzyme usage. When sodium acetate (100 mM, pH 4~6) and sodium phosphate (100 mM, pH 7~9) were used as the buffering salts for the aqueous component (20% v/v), the synthetic yield of the resin increased at higher pH of the aqueous buffer. But when the pHs of the aqueous buffer were 6 and 9, the synthetic yield strongly depended on the types of the buffering salts; if sodium phosphate was used instead of sodium acetate at pH 6, the yield decreased by about 15% and if sodium bicarbonate was used instead of sodium phosphate, the yield decreased by almost 20%. When the pH range of the aqueous buffer was from 4 to 7, the addition of a radical mediator, 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonate) (ABTS), up to 2 mM improved the synthetic yield of the resin by about 10%. TGA experiments revealed that the thermal stability of the resin synthesized in dioxane:water (100 mM sodium phosphate, pH 9) (80:20 v/v) was high having the char yield of 47% upon the heating at $800^{\circ}C$. DCS results showed that the structures of the polymers synthesized in acidic aqueous buffers were different from those of the polymers synthesized in the basic aqueous buffers. However, all the synthesized resins were found to have the property of the thermosetting resins.

Reading Deviations of Glass Rod Dosimeters Using Different Pre-processing Methods for Radiotherapeutic in-vivo Dosimetry (유리선량계의 전처리 방법이 방사선 치료 선량 측정에 미치는 영향)

  • Jeon, Hosang;Nam, Jiho;Park, Dahl;Kim, Yong Ho;Kim, Wontaek;Kim, Dongwon;Ki, Yongkan;Kim, Donghyun;Lee, Ju Hye
    • Progress in Medical Physics
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    • v.24 no.2
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    • pp.92-98
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    • 2013
  • The experimental verification of treatment planning on the treatment spot is the ultimate method to assure quality of radiotherapy, so in-vivo skin dose measurement is the essential procedure to confirm treatment dose. In this study, glass rod dosimeter (GRD), which is a kind of photo-luminescent based dosimeters, was studied to produce a guideline to use GRDs in vivo dosimetry for quality assurance of radiotherapy. The pre-processing procedure is essential to use GRDs. This is a heating operation for stabilization. Two kinds of pre-processing methods are recommended by manufacturer: a heating method (70 degree, 30 minutes) and a waiting method (room temperature, 24 hours). We equally irradiated 1.0 Gy to 20 GRD elements, and then different preprocessing were performed to 10 GRDs each. In heating method, reading deviation of GRDs at same time were relatively high, but the deviation was very low as time went on. In waiting method, the deviation among GRDs was low, but the deviation was relatively high as time went on. The meaningful difference was found between mean reading values of two pre-processing methods. Both methods present mean dose deviation under 5%, but the relatively high effect by reading time was observed in waiting method. Finally, GRD is best to perform in-vivo dosimetry in the viewpoint of accuracy and efficiency, and the understanding of how pre-processing affect the accuracy is asked to perform most accurate in-vivo dosimetry. The further study is asked to acquire more stable accuracy in spite of different irradiation conditions for GRD usage.

Analysis of Prenatal and Postnatal Factors Associated with Complications and Prognosis in Premature Infants with Leukemoid Reaction (백혈병양반응을 보인 미숙아의 합병증과 예후에 관한 산전과 산후 인자에 대한 분석)

  • Kwon, Se-Ho;Lee, Byoung-Kook;Lee, Heun-Ji;Na, So-Young;Lee, Jung-Ha;Park, Su-Yeon;Kang, Eun-Kyeung;Kim, Do-Hyeon;Lee, Kwan;Kim, Hee-Sup
    • Neonatal Medicine
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    • v.15 no.2
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    • pp.151-159
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    • 2008
  • Purpose : This study determined the prenatal and postnatal factors associated with complications and prognosis in premature infants with leukemoid reaction. Methods : We retrospectively reviewed the medical records of premature infants with gestational ages <37 weeks and low birth weights (<2,500 g) who were admitted immediately after birth to the neonatal intensive care unit at the Dongguk University Ilsan Hospital between June 2005 and July 2006. A leukemoid reaction was defined as an absolute neutrophil count (ANC) >30,000/$mm^3$. The infants who had leukemoid reaction comprised the study group, while the remainder of infants made up the control group. The relationships between maternal and neonatal variables and ANC were studied. Results : Leukemoid reaction was detected in 3.1% of the study infants (8 of 252). Factors more frequently associated with infants with leukemoid reaction were as follows: maternal chorioamnionitis, high levels of maternal and infant C-reactive protein, gestational age <37 weeks, birth weight <2,500 g, low Apgar score, prolonged ventilator support, and a high incidence of bronchopulmonary dysplasia (BPD). However, there were no significant differences with respect to the antenatal usage of steroids, the incidences of patent ductus arteriosus, necrotizing enterocolitis, intraventricular hemorrhage, retinopathy of prematurity, and mortality between the two groups. Conclusion : Leukemoid reaction in premature infants was associated with chorioamnionitis and high levels of serum C-reactive protein in mothers and infants, and BPD in infants. These findings suggest that leukemoid reaction is secondary to inflammation caused by infection.

The Effect Of Job Insecurity To The Union Commitment, Dual Commitment and The Union-Related Orientation (고용불안이 노조몰입, 이중몰입, 노사관계행동지향성에 미치는 영향에 관한 연구)

  • Son, Heon-I;Jung, Hyun-Woo
    • Management & Information Systems Review
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    • v.34 no.2
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    • pp.131-149
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    • 2015
  • Recently many organizations have engaged in widespread restructuring as well as more flexible usage of labor in an attempt to cut costs and to increase profit. As a result of lays offs resulting from frequent restructuring, many people no longer consider their jobs as permanent positions. many employees have an increased feeling of job insecurity. There structuring and following downsizing have created an uncertain environment within creased fear offer ther job losses. therefore the study of job insecurity is significant. especially To understand the relationship between job security and union-relation behaviors on the industrial relations. The purpose of this study suggested the strategies to company and union. The purpose of this study is to examine how the union-relation behaviors are influenced by the job security. This study built a exploratory model that there is causal relationship of job security to union commitment, dual commitment, and labor related behaviors. For the verification of this study model, the regression analysis was applied to the surveys of 236 members of union that are located in Busan, Gyeongnam, Ulsan, and Pohang. The result of this research shows that the job insecurity is strongly related to the union commitment and union related behaviors. According to the research, the effect that the job security affects union commitment and union related behaviors are positive. With the research outputs, we have discussed about the academic and pragmatic viewpoint. We proposed comprehensive model to verify how the job insecurity affects the union-related behaviors, and objectively analyzed the model. The research result was opposite to what the existing theories have said that high job insecurity derives high union-related behaviors. This result is meaningful because it is concerned with the social issues-present situation of Korean company, low-employment, unstable employment and so on. Moreover, this research may contribute to expand the aspect of academic research on job insecurity as there are few research conducted in korea. This research also suggests the realistic alternative of union-related behaviors because it is proved that job security can contribute to innovation activities. Also, this research implies that the matter of job insecurity is the basic need of organizational individual and presents that job security is not a notion but the alternative by using of the positional stability and situational control power. The limitation of this research is that it is only utilized the cross-sectional study. To remedy the cross-sectional study, vertical, and serial method of research is needed. And there is no enough sample to secure more comprehensive data as the targets of the research is limited to Busan and Gyeongnam regions. Finally, the measurement tool for job security is needed to be suitably modified to by the South Korea's economic, linguistic, and cultural situation.

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Numerical Simulation for Evaluation the Feasibility of Using Sand and Gravel Contaminated by Heavy Metals for Dam Embankment Materials (중금속으로 오염된 사력재의 댐축조 재료 활용 가능성 평가를 위한 수치 모델링)

  • Suk, Hee-Jun;Seo, Min-Woo;Kim, Hyoung-Soo;Lee, Jeong-Min
    • Economic and Environmental Geology
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    • v.40 no.2 s.183
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    • pp.209-221
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    • 2007
  • Numerical analysis was performed to investigate the effect of heavy metal contamination on neighboring environment in case a dam is constructed by using rockfill materials contaminated by heavy metals. The numerical simulation carried out in this research includes both subsurface flow and contaminant transport in the inside of the CFRD(Concrete Faced Rockfill Dam), using two commercial programs, SEEP2D and FEMWATER. The three representative cases of scenarios were chosen to consider a variety of cases occurring in a dam site; (1) Scenario 1 : no crack in the concrete face slab, (2) Scenario 2 : a crack In the upper part of face slab, and (3) Scenario 3 : a crack between plinth and face slab in the lower part of face slab. As a result of seepage analysis, the amount of seepage in scenario 2 was calculated as $14.31\sim14.924m^3/day$ per unit width, corresponding to the 1,000 times higher value than that in other scenarios. Also, in the simulation of contaminant transport by using FEMWATER, specified contaminant concentration of 13 ppb in main rockfill zone was set to consider continuous leakage from the rock materials. Through the analysis of contaminant transport, we found that elapsed times to take for the contaminant concentration of about 2 ppb to arrive at the end of a dam are as follows. Scenario 1 has the elapsed time of 55,000 years. In Scenario 2. it is 50 years. Finally, scenario 3 has 27,000 years. The rapid transport of the contaminant in scenario 2 was attributed to greater seepage flow by 500 times than other scenarios. Although, in case of upper crack in the face slab, it was identified that the contaminant might transport to the end of a dam within 100 years with about 2 ppb concentration, however, it happened that the contaminant was hardly transported out of the dam in other scenarios, which correspond to either no crack or a crack between plinth and face slab. In conclusion, the numerical analysis showed that the alternative usage of the contaminated sand and gravel as the dam embankment material can be one of the feasible methods with the assumption that the cracks in a face slab could be controlled adequately.

A Study of material analysis and its experimentation of metamorphosis and its utilities in Copper Alloy plates for contemporary metal craft (현대금속공예용 동합금판의 재료분석과 형질변환 실험 및 응용에 관한 연구)

  • Lim, Ock-Soo
    • Archives of design research
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    • v.17 no.4
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    • pp.241-250
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    • 2004
  • In this research, the copper alloy plates C2200, C5210, C7701, C8113 were selected to make datum and to identify further usage of metal craft experimentation. For its experimentation, the general welding and TIG welding methods were researched; for 2nd experimentation, the Reticulation and Electroforming skill's differences in color and temperature were researched. With these methods 3 different kinds of works are introduced for sample studies. For this research, Dr. Lee, Dong-Woo who works in Poongsan Metal Co, supported 4 kinds of copper alloy metals. Which are Commercial bronze (Cu-Zn), Deoxidiged Copper(Cu-Sn-P), Nickel Silver (Cu-Ni-Zn), and White Bronze (Cu-Ni); they were applied partly and wholly by the method of Laminatin, Reticulation, Fusing, and Electroforming skills. In case of C2200, the brass, the A. C. TIG welding method is better under 2mm slight plate; the D.C. TIG welding is better upper 2mm plate; and 250~300$^{\circ}C$ is recommended for remain heat treatment. In case of C5210, not having Hydrogen in high temperature return period, doesn't need Oxygen in high temperature and hardening in comparative high temperature neither, it is good for welding. It contains Sn 2-9% ad P 0.03-0.4% generally; and in accordance with the growth rate of Sn contain amount, the harden temperature boundary become broad. In case of cold moment after welding, they are recommended that higher speed TIG welding, smaller melting site and less than 200$^{\circ}C$ for pre-heating temperature. In case of C7701, the 10-20% Ni, 15-30% Zn are widely used.. If it is upper 30% Zn, it become (${\alpha}+{\beta}$) system and adhesive power rate become lower, and the productivity become lower in low temperature but the productivity become higher in high temperature. Nickel Silver's resistance of electricity is well; and the heatproof and incorrodibility is good, too. Lastly, in case of C8113, good at persistence in salty and grind; high in strength of high temperature. In case of white brass, contain 10-30% Nickel and hardened in high temperature and become single phrase. For these reason, the crystallization particles easily become large, if the resistance become higher small amount of Pb, P, S separation rate become higher.

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