• Journal of Korean Society of Environmental Engineers
• /
• v.22 no.7
• /
• pp.1357-1364
• /
• 2000

Our study was performed to evaluate the effect of leaching parameters including the physicochemical characteristics and the fractionated composition of heavy metals on the release of heavy metals in fly ash discharged from MSWI. Leaching parameters such as pH, CEC, particle size, and exchangeable fraction among the fractional composition classified by sequential extraction procedure are considered. The leaching rate of heavy metal released by KSLT method is largely dependent on the pH of fly ash. The effect of pH on the release of heavy metals is different from elements. It appears that the leaching rate of cadmium and copper decreases with increasing pH, while lead and zinc increases at the condition of neutral or strong alkali condition, which suggests that the leaching of heavy metals are limited by the solubility. It is found that the effect of CEC is similarly to that of pH, $D_{10}$ among the particle size of fly ash is negative correlated with the concentration of heavy metals leached by KSLT method. In the case of exchangeable fraction, the leaching rate of heavy metals is linearly correlated with the exchangeable fraction for the fly ash below 40 meq/l00g of CEC, but not related out of the range.

• Journal of the Institute of Electronics Engineers of Korea SC
• /
• v.49 no.3
• /
• pp.38-46
• /
• 2012

Atrial fibrillation is needed to be detected at paroxysmal stage and to be treated. But, paroxysmal atrial fibrillation ECG is hardly obtained with 12-lead electrocardiographs but Holter systems. Presently, the averaged beat subtraction(ABS) method is solely used to estimate atrial fibrillatory waves even with somewhat large residual error. As an alternative, in this study, we suggested an ESAF(event-synchronous adaptive filter) based algorithm, in which the AF ECG was treated as a primary input and event-synchronous impulse train(ESIT) as a reference. And, ESIT was generated so to be synchronized with the ventricular activity by detecting QRS complex. We tested proposed algorithm with simulated AF ECGs and real AF ECGs. As results, even with low computational cost, this ESAF based algorithm showed better performance than the ABS method and comparable performance to algorithm based on PCA(principal component analysis) or SVD(singular value decomposition). We also proposed an expanded version of ESAF for some AF ECGs with multi-morphologic ventricular activities and this also showed reasonable performance. Ultimately, with Holter systems including our proposed algorithm, atrial activity signal can be precisely estimated in real-time so that it will be possible to calculate atrial fibrillatory rate and to evaluate the effect of anti-arrhythmic drugs.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.35 no.1
• /
• pp.136-143
• /
• 2008

Infections involved with the oral and maxillofacial area are associated with various anatomical structures. If the proper treatment is not done in an immediate period, the infections will be quite fatal. The causes of the infections are numerous, but the most common cause of odontogenic infections in children is a dental caries. It is known to lead to some kinds of diseases such as periapical abscess, cellulitis, osteomyelitis, Ludwig's angina, toxic shock syndrome and so on. The common pathogenic sequence of fascial abscess is a necrotic pulpal inflammation in the form of dentoalvelor abscess which spreads over and gradually penetrates into the fascial membranes through the cortical bones and finally contracts the potential fascial spaces. If the infections of oral maxillofacial area were penetrated into the surrounding soft tissues, then they would diffuse into the directions of the least tissue resistance along with the connective tissues and the fascial spaces. These infections can be properly cured by tooth extraction, endodontic therapy, surgical treatment including Incision & drainage and antibiotics. The purpose of the cases is to report the satisfactory treatment results in the patients derived from the canine fascial space abscesss or buccal fascial space ones of the odontogenic origin.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.40 no.4
• /
• pp.335-341
• /
• 2013

Impacted maxillary canines are the most frequently impacted teeth after the third molars. The exact etiology of impacted maxillary canines is unknown, but several complications may result from impacted maxillary canines. An early detection of ectopically erupting teeth can lead to performing interceptive treatment such as early extraction of primary canine and provide the best long-term results. In the absence of prevention, clinicians should consider orthodontic treatment followed by surgical exposure of the canine to bring it into occlusion. However, in cases when the finding ectopically erupting teeth and severe root resorption of adjacent teeth are found late, malposed canine can replace the injured teeth. In these presented cases, early diagnosis and treatment of ectopic eruption and root resorption were not performed. The maxillary incisor replacement with ectopically erupting canine can be the alternative treatment of choice with successful results. The reconstructed canine is planned to be checked periodically for the condition of composite resin restoration. Orthodontic treatment and dental implant are planned. This report shows that when early diagnosis was not done, maxillary incisor replacement with ectopically erupting canine could prevent uncertain prognosis of the adjacent teeth with root resorption and provide esthetic satisfactory with time saved and cost reduced.

• Informatization Policy
• /
• v.23 no.3
• /
• pp.26-42
• /
• 2016

Recently, with the rapid growth of the O2O market, Fintech combining the finance and ICT technology is drawing attention as innovation to lead "O2O of finance", along with Fintech-based payment, authentication, security technology and related services. For new technology industries such as Fintech, technical sources, related systems and regulations are important but previous studies on Fintech lack in-depth research about systems and technological trends of the domestic Fintech industry. Therefore, this study aims to analyze domestic Fintech trends and find the insights for the direction of technology and systems of the future domestic Fintech industry by comparing Kakao Pay and Samsung Pay, the two domestic representative mobile payment services. By conducting a complete enumeration survey about the tweets mentioning Fintech until June 2016, this study visualized topics extraction, sensitivity analysis and keyword analyses. According to the analysis results, it was found that various topics have been created in the technologies and systems between 2014 and 2016 and different keywords and reactions were extracted between topics of Samsung Pay based on "devices" such as Galaxy and Kakao Pay based on "service" such as KakaoTalk. This study contributes to analyzing the unstructured data of social media by period by using social media mining and quantifying the expectations and reactions of consumers to services through the sentiment analysis. It is expected to be the foundation of Fintech industry development by presenting a strategic direction to Fintech related practitioners.

• Journal of Korean Society of Environmental Engineers
• /
• v.32 no.2
• /
• pp.185-192
• /
• 2010

The objective of this study was to investigate the effectiveness of stabilization for army firing range soil highly contaminated with Pb (total Pb: 29,000 mg/kg) using calcined waste oyster shells. The calcination was conducted to activate quicklime from calcite. In order to evaluate the effectiveness of calcination, both natural oyster shells (NOS) and calcined oyster shells (COS) were applied to the Pb contaminated soil. Stabilization was conducted by mixing the contaminated soil with oyster shell media at 5-20 wt% and cured for 28 days. Following 28 days of curing, Pb leachability was measured based on the Korean Standard Test method (0.1 N HCl extraction). The treatment results showed that the COS treatment outperformed the NOS treatment. All of the NOS treatments failed to meet the Korean warning standard of 100 mg/kg. However, the Pb concentrations were significantly reduced to 47 mg/kg and 3 mg/kg upon 15 wt% and 20 wt% COS treatments, respectively which passed the Korean warning standard. Moreover, -#20 mesh materials were more effective than the -#10 mesh materials in effectively reducing Pb leachability. The scanning electron microscopy (SEM)-energy dispersive X-ray spectroscopy (EDX) results indicated that Pb immobilization was strongly linked to Al and Si.

• Journal of Dental Rehabilitation and Applied Science
• /
• v.31 no.3
• /
• pp.253-261
• /
• 2015

Chronic periodontitis involves subsequent loss of teeth, and if left untreated, can lead to adjacent teeth drifting and supraeruption of the rest dentition. Careful consideration has to be given when deciding extraction of remaining teeth in treatment of periodontally compromised dentitions. For tooth-supported fixed partial dentures or removable partial dentures, periodontally compromised teeth are extracted due to possible early failure from functional overload, but for implant restoration, the teeth could be used as supports for fixed partial dentures because implants can reduce overload on teeth. The remaining natural teeth can help clinicians restoring vertical dimension and normal occlusal plane in full mouth rehabilitation because it conserves patients' proprioceptive response. This clinical report describes treatment of a patient who has a few remaining teeth and supraeruption of the rest dentition from severe chronic periodontitis. Satisfactory clinical result was achieved with full mouth rehabilitation using a few teeth and implants.

• Journal of Intelligence and Information Systems
• /
• v.22 no.4
• /
• pp.87-107
• /
• 2016

Understanding market convergence has became essential for small and mid-size enterprises. Identifying convergence items among heterogeneous markets could lead to product innovation and successful market introduction. Previous researches have two limitations. First, traditional researches focusing on patent databases are suitable for detecting technology convergence, however, they have failed to recognize market demands. Second, most researches concentrate on identifying the relationship between existing products or technology. This study presents a platform to identify the opportunity of market convergence by using product databases from a global B2B marketplace. We also attempt to identify convergence opportunity in different industries by applying Structural Hole theory. This paper shows the mechanisms for market convergence: attributes extraction of products and services using text mining and association analysis among attributes, and network analysis based on structural hole. In order to discover market demand, we analyzed 240,002 e-catalog from January 2013 to July 2016.

• Journal of the Korean GEO-environmental Society
• /
• v.11 no.11
• /
• pp.63-75
• /
• 2010

There are several remediation technologies for heavy metal contaminated soils but increasing cost limits the application of the technology if the contaminated area is large. Therefore, stabilization, which blocks the release of heavy metals or makes slow the release, is one of the applicable technology for the heavy metal contaminated soil. Current study is an applicability test for a smelter area with various stabilizer such as magnetite, hematite, zeolite-A, zeolite-X, zeolite-Y, zinc oxide, calcium oxide, carbon trioxide, manganese oxide, manganese dioxide, fish bone, sodium phosphate. The soil contaminated with arsenic, lead, copper, nickel, and zinc could not be stabilized only one stabilizer which is known to have stability for certain metal. Many of the stabilizer works for a few metal but not all of the heavy metal. In several cases, stabilizers increase the release of the other metals while they stabilize some metals. In general, the stabilizing efficiency was increased with time. For Ni, Pb, calcium oxide, carbon trioxide, manganese oxide had good stabilizing effect in water extractable portion. For Cu, manganese oxide, zeolite showed good results especially in the exchangeable portion of the sequential extraction. For As, magnetite had good ability but most of the metal oxide which showed good result for other heavy metals increased with the release of As. Current study suggest that multiple stabilizers are needed for the contaminated soil and dose of the stabilizer and stabilizing time should be carefully considered for the soil contaminated with various metals.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.17 no.12
• /
• pp.2960-2965
• /
• 2013

Customized services for individuals in analysis of recently collected GPS information have been investigated in various aspects. As the size of collected GPS data gets larger, a variety of services is being released accordingly. Existing studies, however, are limited to presenting service models for users while there is little study on developing intelligent computing technologies in the introduction of GPS information into the system. This study suggests an algorithm to analyze traffic information by introducing GPS information into the system in order to take the lead among intelligent computing technologies. The suggested algorithm analyzes a map by means of the collected vehicle GPS information and sectional traffic information interpretation method; thus, the computer judges the traffic information collected by humans. The experiment result shows that the traffic information was properly analyzed upon the utilization of the given data. Although a small quantity of analyzed data was less reliable, the system maintained high reliability as the data was sufficient.