• Economic and Environmental Geology
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• v.53 no.4
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• pp.347-362
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• 2020

Iron (hydro)oxides in aqueous environments are primarily formed due to mining activities, and they are known to be typical colloidal particles disturbing surrounding environments. Among them, hematites are widespread in surface environments, and their behavior is controlled by diverse factors in aqueous environments. This study was conducted to elucidate the effect of environmental factors, such as ionic composition and strength, pH, and natural organic matter (NOM) on the behavior of colloidal hematite particles. In particular, two analytical methods, such as dynamic light scattering (DLS) and single-particle ICP-MS (spICP-MS), were compared to quantify and characterize the behavior of colloidal hematites. According to the variation of ionic composition and strength, the aggregation/dispersion characteristics of the hematite particles were affected as a result of the change in the thickness of the diffuse double layer as well as the total force of electrostatic repulsion and van der Walls attraction. Besides, the more dispersed the particles were, the farther away the aqueous pH was from their point of zero charge (PZC). The results indicate that the electrostatic and steric (structural) stabilization of the particles was enhanced by the functional groups of the natural organic matter, such as carboxyl and phenolic, as the NOM coated the surface of colloidal hematite particles in aqueous environments. Furthermore, such coating effects seemed to increase with decreasing molar mass of NOM. On the contrary, these stabilization (dispersion) effects of NOM were much more diminished by divalent cations such as Ca²⁺ than monovalent ones (Na⁺), and it could be attributed to the fact that the former acted as bridges much more strongly between the NOM-coated hematite particles than the latter because of the relatively larger ionic potential of the former. Consequently, it was quantitatively confirmed that the behavior of colloidal hematites in aqueous environments was significantly affected by diverse factors, such as ionic composition and strength, pH, and NOM. Among them, the NOM seemed to be the primary and dominant one controlling the behavior of hematite colloids. Meanwhile, the results of the comparative study on DLS and spICPMS suggest that the analyses combining both methods are likely to improve the effectiveness on the quantitative characterization of colloidal behavior in aqueous environments because they showed different strengths: the main advantage of the DLS method is the speed and ease of the operation, while the outstanding merit of the spICP-MS are to consider the shape of particles and the type of aggregation.

• Journal of KIISE:Information Networking
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• v.32 no.3
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• pp.279-290
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• 2005

Recently, as the serious damage caused by DDoS attacks increases, the rapid detection and the proper response mechanisms are urgent. However, existing security mechanisms do not effectively defend against these attacks, or the defense capability of some mechanisms is only limited to specific DDoS attacks. In this paper, we propose a detection architecture against DDoS attack using data mining technology that can classify the latest types of DDoS attack, and can detect the modification of existing attacks as well as the novel attacks. This architecture consists of a Misuse Detection Module modeling to classify the existing attacks, and an Anomaly Detection Module modeling to detect the novel attacks. And it utilizes the off-line generated models in order to detect the DDoS attack using the real-time traffic. We gathered the NetFlow data generated at an access router of our network in order to model the real network traffic and test it. The NetFlow provides the useful flow-based statistical information without tremendous preprocessing. Also, we mounted the well-known DDoS attack tools to gather the attack traffic. And then, our experimental results show that our approach can provide the outstanding performance against existing attacks, and provide the possibility of detection against the novel attack.

• Journal of Food Hygiene and Safety
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• v.22 no.1
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• pp.29-36
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• 2007

The using frequency of processed foods and dietician's perception against management of food service at 98 food service institutions located in Jeollabuk-Do were surveyed. Food service institutions included 13 hospitals,38 schools,40 enterprises, and 7 others. Single menu (75.5%) with two (33.7%) or three (57.1%) side dish was offered. In addition, the offering ratio of boiled water and spring water was 37.8 and 32.7%, respectively. The processed foods with high using frequency were kochujang (1.19), sesame oil (1.22), and doenjang (1.30), but that of leek, onion, Chinese cabbage, and radish were 4.95, 4.62, 4.60, and 4.26, respectively. Dietician's major affairs in all type of food service institutions were cooking (64.3%), purchase (48.0%), and personnel managements (39.8%). Dieticians, however, had a low perception against safety and nutrition management. Therefore, in order to prevent the outbreak of food-borne diseases, we estimated that the education and the conversion of dietician' perception against safety and nutrition management were needed.

• Food Science of Animal Resources
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• v.20 no.2
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• pp.159-165
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• 2000

Glycomacropeptide(GMP) was purified from cheese whey which is obtaining as a byproduct in cheese producing. Cheese whey was first concentrated 10 times with a ultrafiltration aparratus, and then heated at 95$^{\circ}C$ for 5 min. The concentrated fraction was centrifuged at 20,000$\times$g for 30 min to remove fat layer. The supernatant layer enriched GMP protein was fractionated by ion exchange chromatography on DEAE-Sepharose Fast Flow column. GMP was bound to DEAE resin and eluted with 0.1~0.25 M NaCl when using a linear NaCl gradient from 0 M to 0.5 M. The purified GMP gave a single band of 24 kDa which seems to be trimer molecular weight in SDS-PAGE, and migrated to the same molecular weight with control GMP obtained commercially. Its amino acid composition were consistent with that of standard GMP. About 0.71 g of GMP was recovered from 1 L of cheese whey. These results indicate that glycomacropeptide could be simply purified from cheese whey by using ultrafiltration and DEAE column chromatography.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.8
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• pp.1270-1277
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• 2014

This study investigated the quality characteristics of instant rice noodles manufactured with broken rice flour as an application of rice-processed products. We examined the physicochemical characteristics of common rice flour (CRF), broken rice flour (BRF), and CRF mixed with BRF (CBRF). Futhermore, instant rice noodles were manufactured with these three types of rice flour, and their quality and sensory characteristics were also investigated. Damaged starch content and water-binding capacity of rice flour were highest in BRF. Particle size of rice flour was significantly different among the three types. RVA pasting viscosities of BRF and CBRF were higher than that of CRF. Volume after cooking of instant rice noodles increased in rice noodles made with broken rice flour (BRN). Turbidity and cooking loss of BRN were higher than those of common rice noodles (CON). For texture properties, CON displayed the highest hardness, adhesiveness, and chewiness. In the sensory evaluation, springiness and overall acceptability values of CON were significantly higher than those of other rice noodle types (BRN and CBRN). In conclusion, BRN showed increased cooking loss and turbidity with reduced texture and overall acceptability values. The results of this study suggest that added amount of CRF may significantly increase the overall quality of instant rice noodles prepared with BRF.

• Tuberculosis and Respiratory Diseases
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• v.45 no.4
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• pp.714-722
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• 1998

Background: Rifampicin (RFP) is a key component of the antituberculous short-course chemotherapy and the RFP resistance is a marker of multi-drug resistant (MDR) tuberculosis. RPoB gene encodes the $\beta$-subunit of RNA polymerase of M. tuberculosis which is the target of RFP. And the mutations of rpoB gene have been found in about 96% of rifampicin resistant clinical isolates of M. tuberculosis. So in order to find a rapid and clinically useful diagnostic method in identifying the RFP resistance, we compared the PCR -line probe method with PCR-SSCP for the detection of the rpoB gene mutation in cultured M. tuberculosis. Methods: 45 clinical isolates were collected from patients who visited Sung Kyun Kwan University Hospital. The RFP susceptibility test was referred to the referral laboratory of the Korean Tuberculosis Institute. 33 were rifampicin resistant and 12 were rifampicin susceptible. The susceptibility results were compared with the results of the PCR-BSCP and PCR-line probe method. Results: We could find rpoB mutations in 27/33(81.8%) RFP-resistant strains by PCR-line probe method, and in 23/33 (69.7%) by PCR-SSCP and there was no significant difference between two methods. There was no mutation in rifampicinn susceptible strains by both methods. Conclusion: PCR-line probe method would be a rapid, sensitive and specific method for the detection of rifampicin resistant Mycobacterium tuberculosis.

• Journal of the Korean Institute of Landscape Architecture
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• v.38 no.1
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• pp.74-83
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• 2010

This study is a development plan of a resort in a regional center that aims to generate tourism consumptions that have ripple effects on the regional economy by developing abandoned mine complexes in Daechon. Thanks to economic growth, the public awareness of tourism has changed. Hence, want for tourism influences development and advancement of recreational spaces, combining with various cultural contents. Development associated with environmental issues caused by modernization has become a major issue. At this point, to rediscover and specialize industrial complexes of bygone days as tourism resources signifies regeneration of regional resources. This study aims to find a solution for appropriate tourism development as part of the measures to revitalize the regional economy in underdeveloped areas and to improve the polluted environment. The result of the study is summarized as follows: First, in regional development alongside the development of a resort complex, it is important to construct environmental similarities. Minimizing differences in landscape structures is especially necessary because it will cause tourism resources in a regional center to be naturally linked to regional activities. These will then be recognized as attractions in the neighborhood. Therefore, it is desirable to reflect a spatial structure for environmental convergence, and, at the same time, to fulfill operation purposes by space through differentiation of movement lines. Second, in utilization of existing environmental resources, it is desirable to express localities and to develop differentiated elements. Facilities should not be homogenized, attaching importance to trends. Therefore, in establishing a development plan, it is important to have an attitude to accept existing roles and functions in a transformative manner. Third, recreational facilities in resort spaces generally have the problems of being uniformly planned as part of a development project and being limited to landscape facilities. Introduction of specialized facilities that can be reconciled with the regional environment and that can be open influences the landscape structure of the entire region and brings ripple effects as key facilities for activation of tourism.

• Journal of Korean Society of Archives and Records Management
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• v.10 no.2
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• pp.75-99
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• 2010

Digital resources are widely used in our modern society. However, we are facing fundamental problems to maintain and preserve digital resources over time. Several standard methods for preserving digital resources have been developed and are in use. It is widely recognized that metadata is one of the most important components for digital archiving and preservation. There are many metadata standards for archiving and preservation of digital resources, where each standard has its own feature in accordance with its primary application. This means that each schema has to be appropriately selected and tailored in accordance with a particular application. And, in some cases, those schemas are combined in a larger frame work and container metadata such as the DCMI application framework and METS. There are many metadata standards for archives of digital resources. We used the following metadata standards in this study for the feature analysis me metadata standards - AGLS Metadata which is defined to improve search of both digital resources and non-digital resources, ISAD(G) which is a commonly used standard for archives, EAD which is well used for digital archives, OAIS which defines a metadata framework for preserving digital objects, and PREMIS which is designed primarily for preservation of digital resources. In addition, we extracted attributes from the decision tree defined for digital preservation process by Digital Preservation Coalition (DPC) and compared the set of attributes with these metadata standards. This paper shows the features of these metadata standards obtained through the feature analysis based on the records lifecycle model. The features are shown in a single frame work which makes it easy to relate the tasks in the lifecycle to metadata elements of these standards. As a result of the detailed analysis of the metadata elements, we clarified the features of the standards from the viewpoint of relationships between the elements and the lifecycle stages. Mapping between metadata schemas is often required in the long-term preservation process because different schemes are used in the records lifecycle. Therefore, it is crucial to build a unified framework to enhance interoperability of these schemes. This study presents a basis for the interoperability of different metadata schemas used in digital archiving and preservation.

• Journal of Dental Rehabilitation and Applied Science
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• v.24 no.4
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• pp.337-349
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• 2008

Despite an improved bone reactions of Mg-incorporated implants in the animals, little yet has been carried out by the experimental investigations in functional loading conditions. This study investigated the clinical and histologic parameters of osseointegrated Mg-incorporated implants in delayed loading conditions. A total of 36 solid screw implants (diameter 3.75 mm, length 10mm) were placed in the mandibles of 6 beagle dogs. Test groups included 18 Mg-incorporated implants. Turned titanium Implants served as control. Gold crowns were inserted 3 months. Radiographic assessments and stabilitytests were performed at the time of fixture installation, $2^{nd}$ stage surgery, 1 and 3 months after loading. Histological observations and morphometrical measurements were also performed. Of 36 implants, 32 displayed no discernible mobility, corresponding to successful clinical function. There was no statistically significant difference between test implants and controls in marginal bone levels (p=0.413) and RFA values. The mean BIC % in the Mg-implants was $54.4{\pm}20.2%$. The mean BIC % in the turned implant was $48.9{\pm}8.0%$. These differences between the Mg-implant and control implant were not statistically significant (P=0.264). In the limitation of this study, bone-to-implant contact (BIC) and bone area of Mg-incorporated oxidized implant were similar to machine-turned implant. The stability analysis showed no significantly different ISQ values and marginal bone loss between two groups. Considering time-dependent bone responses of Mg-implant, it seems that Mg-implants enhanced bone responses in early loading conditions and osseointegrated similarly to cp Ti implants in delayed loading conditions. However, further investigations are necessary to obtain long-term bone response of the Mg-implant in human.

• Journal of Life Science
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• v.7 no.4
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• pp.392-401
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• 1997

The poliovirus is a small, and non-enveloped virus. The RNA genome of poliovirus is continuous, linear, and has a single open reading frame. This polyprotein precursor is cleaved proteolytically to yield mature products. Most of the cleavages occur by viral protease. The mature proteins derived from the P1 polyprotein precursor are the structural components of the viral capsid. The initial cleavage by 2A protease is indirectly involved in the cleavage of a cellular protein p220, a subunit of the eukaryotic translation initiation factor 4F. This cleavage leads to the shut-off of cap-dependent host cell translation, and allows poliovirus to utilize the host cell machinery exclusively for translation its own RNA, which is initiated by internal ribosome entry via a cap-independent mechanism. The functional role of the 2B, 2C and 2BC proteins are not much known. 2B, 2C, 2BC and 3CD proteins are involved in the replication complex of virus induced vesicles. All newly synthesized viral RNAs are linked with VPg. VPg is a 22 amino acid polypeptide which is derived from 3AB. The 3C and 3CD are protease and process most of the cleavage sites of the polyprotein precursor. The 3C protein is also involved in inhibition of RNA polymerase II and III mediated transcription by converting host transcription factor to an inactive form. The 3D is the RNA dependent RNA polymerase. It is known that poliovirus replication follows the general pattern of positive strand RNA virus. Plus strand RNA is transcribed into complementary minus strand RNA that, in turn, is transcribed for the synthesis of plus strand RNA is transcribed into complementary minus strand RNA that, in turn, is transcribed for the synthesis of plus strand RNA strands. Poliovirus RNA synthesis occurs in a membranous environment but how the template RNA and proteins required for RNA replication assemble in the membrane is not much known. The RNA requirements for the encapsidation of the poliovirus genome (packaging signal) are totally unknown. The poliovirus infection cycle lasts approximately 6 hours.