• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.2 no.2 s.3
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• pp.43-54
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• 2003

As the demand for ubiquitous mobile wireless Internet grows, vehicles are receiving a lot of attention as new networking platforms. The demand for 4G all-IP networks encourages vehicle networks to be connected using IPv6. By means of network mobility (NEMO) support, we can connect sensors, controllers, local ,servers as well as passengers' devices of a vehicle to the Internet through a mobile router. The mobile router provides the connectivity to the Internet and mobility transparency for the rest of the mobile nodes of an in-vehicle nv6 network. So, it is .important for the mobile router to assure reliable connection and a sufficient data rate for the group of nodes behind it. To provide reliability, this paper proposes an adaptive multihoming architecture of multiple mobile routers. Proposed architecture makes use of different mobility characteristics of different vehicles. Simulation results with different configurations show that the proposed architecture increases session preservation thus increases reliability and reduces packet loss. We also show that the proposed architecture is adaptive to heterogeneous access environment which provide different access coverage areas and data rates. The result shows that our architecture achieves sufficient data rates as well as session preservation.

• Journal of the Institute of Electronics and Information Engineers
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• v.49 no.11
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• pp.118-131
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• 2012

The existing electronic tagging system traces the location of a sex offender through communicating with GPS satellites and mobile phone base stations in order to prevent repeated crimes. However, the GPS satellite communication method does not work well in the interiors of downtown buildings or on the subways where it is difficult to receive satellite signals. In such cases, the location can be traced through communication with mobile phone base stations. But the distance between mobile phone base stations is several hundred meters, and as a result the margin of error for location tracing can be maximum of 2km in accuracy reduction. Take for example, if a kindergarten is located on the 2nd floor and a coffee shop and the sex offender are located on the 3rd floor in a 5-story building that is downtown, the existing electronic tagging system cannot trace the location of the sex offender as the GPS satellite communication does not work in the interior of the building and the exact floor that the sex offender is located on cannot be recognized through communication with mobile phone base stations. This occurrence is a big problem for the existing electronic tagging system, which is based on position recognition. Therefore, this study suggests a smart electronic tagging system that can monitor sex offenders by using a Ubiquitous Sensor Network in such extreme situations where position recognition is not possible.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.44 no.1
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• pp.33-39
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• 2007

LonWorks over IP (LonWorks/IP) virtual device network (VDN) is an integrated form of LonWorks device network and IP data network. LonWorks/IP VDN can offer ubiquitous access to the information on the factory floor and make it possible for the predictive and preventive maintenance on the factory floor. Timely response is inevitable for predictive and preventive maintenance on the factory floor under the real-time distributed control. The network induced uncertain time delay deteriorates the performance and stability of the real-time distributed control system on LonWorks/IP virtual device network. Therefore, in order to guarantee the stability and to improve the performance of the networked distributed control system the time-varying uncertain time delay needs to be compensated for. In this paper, under the real-time distributed control on LonWorks/IP VDN with uncertain time delay, a control scheme based on disturbance observer and ZPETC(Zero Phase Error Tracking Controller) phase lag compensator is proposed and tested through computer simulation. The result of the proposed control is compared with that of internal model controller (IMC) based on Smith predictor and disturbance observer. It is shown that the proposed control scheme is disturbance and noise tolerant and can significantly improve the stability and the tracking performance of the periodic reference. Therefore, the proposed control scheme is well suited for the distributed servo control for predictive maintenance on LonWorks/IP-based virtual device network with time-varying delay.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.36 no.3
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• pp.341-348
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• 2016

Harbor facilities require long-term durability and safety, and also maintain the performance requirement until the durability life. However, existing harbor facilities are becoming superannuated with durable years and durability is declined by erosion of the sea and damage from sea. In addition, harbor facilities will be in demand for the expansion of harbor and offshore structures with rising economic power by enhancement of domestic industry and increase of import and export. Therefore, in this study, two kinds of nondestructive test (NDT) techniques (schmidt rebound hammer and ultrasonic sensor) are verified for the effective maintenance of underwater concrete structures including harbor facilities. Sea field applicability of Schmidt hammer and ultrasonic sensor was verified by comparing field test result with sea field test result and also deduced the compressive strength estimation equation by depth of the water. On the basis of the sea field test result, compressive strength estimation equation which was deduced by multiple regression analysis indicated highest accuracy compared to other equations, especially it will be more likely to be used in underwater because of the depth of water correction. In the future, if schmidt hammer and ultrasonic sensor which were invented as waterproofing are used with ROV (Remotely Operated Vehicle), it will be possible to make a diagnosis of high reliability for underwater concrete structures and set up a ubiquitous concept of NDT system.

• Information Systems Review
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• v.8 no.2
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• pp.29-49
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• 2006

The introduction of the Digital Economy has formed a new market producing and trading information. Depending on the current contexts, each user evaluates identical information differently. It is difficult, even though important, to create and deliver the information customized to individual users by using some factors as time, location, and their personal characteristics. Information value, therefore, could be influenced by the capability of information systems to delivery useful information based on individual contexts to the right user immediately at the right time. From this point of view, we argue mobile systems which are able to be aware of individual contexts and deliver contextual information in real time can improve information value easily than other systems can. This research presents the results of an empirical test about antecedents to mobile advertising value. Though context relevance doesn't influence directly mobile advertising value, it plays an important role enhancing information usefulness which has great influence on mobile advertising value. Moreover, to supply information connected with users' context overcomes the effect of irritation. Lastly, entertainment can improve mobile advertising value as satisfying user's hedonic desire beyond the information source supporting decision making.

• Journal of Nutrition and Health
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• v.40 no.sup
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• pp.3-8
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• 2007

Sugars are a ubiquitous component of our food supply and are consumed as a naturally occurring component of many foods and as additions to foods during processing, preparation, or at the table. Most fruits and dairy products are high in sugars and thus naturally occurring sugars are consumed as part of a healthy diet. Some countries developed recommended daily intake figures(daily values : DVs or guideline daily amounts: GDA) for nutrients, and some countries, but not most have developed DV/GDA for total sugars. Dietary Reference Intakes for Koreans established by the Korean Nutrition Society in 2005, did not include the reference values for total sugar or added sugar. The committee on Dietary Reference Intakes for sugar was constituted in 2006 and discussed whether to special added sugars or total sugar. Although added sugars are not chemically or physiologically different from naturally occurring sugars, many foods and beverages that are major sources of added sugars have lower micronutrient densities compared with foods and beverages that are major sources of naturally occuring sugars. But it was so hard to calculate a dietary intake of added sugar for Korean people, because there was insufficient information about contents of added sugar during processing or preparation of Korean food. Currently Korean or US food labels contain information on total sugars per serving but do not distinguish between sugars naturally present in food and added sugars. Therefore the committee decided to set the reference value for total sugar for Koreans. According to the recommended diet pattern for Koreans suggested by the Korean Nutrition Society, estimated sugar intake from the sugar containing food based on 2,000 kilocalories is 67 g or 13% of total energy. Based on the data available on risk of obesity, hypertension, hyperlipidemia, insulin resistance, and metabolic syndrome from the analysis of Korean NHANES, it was insufficient evidence to set a UL for total sugar, but tended to increase serum LDL cholesterol and obesity at over 20-25% of energy from total sugar when consumed with high carbohydrates. Therefore the committee on Dietary Reference Intakes for sugar set the Acceptable Macronutrient Distribution Range for total sugar as 10-20% of total energy intake.

• Journal of Life Science
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• v.24 no.12
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• pp.1291-1300
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• 2014

Peroxiredoxins (Prxs) are a ubiquitous family of antioxidant enzymes that participate in a variety of biological processes, including $H_2O_2$-mediated signal transduction, molecular chaperoning, and mitochondrial function. In this study, we isolated and characterized a Prx 2 cDNA from abalone (Haliotis discus hannai). The abalone Prx 2 cDNA encoded a 199-amino acid polypeptide that belongs to a class of typical 2-Cys Prxs that contain peroxidatic and resolving cysteines. The deduced abalone Prx 2 protein showed strong homology (64-99%) with Prx 2 proteins from other species, including mollusk, fish, amphibians, and mammals, and it was most closely related to disk abalone (H. discus discus) Prx 2. Abalone Prx 2 mRNA was ubiquitously detected in tested tissues, and its expression was comparatively high in the mantle, gills, liver, foot, and digestive duct. The expression level of abalone Prx 2 mRNA was 106.7-fold, 51.9-fold, and 437.8-fold higher, respectively, in the gills, digestive duct, and liver than in the muscles. The expression level of abalone Prx 2 mRNA in the liver peaked at 6 hr postinfection with Vibrio parahemolyticus and decreased at 12 hr postinfection. The expression level of abalone Prx 2 mRNA in hemocytes was drastically increased at 1 hr postinfection with V. parahemolyticus. These results suggest that abalone Prx 2 is conserved through evolution and that it may play a role similar to that of its mammalian counterpart.

• Journal of the Korea institute for structural maintenance and inspection
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• v.14 no.6
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• pp.171-178
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• 2010

Pipeline structure is one of core underground infrastructure which transports primary sources. Since the almost pipeline structures are placed underground and connected each other complexly, it is difficult to monitor their structural health condition continuously. In order to overcome this limitation of recent monitoring technique, recently, a Ubiquitous Sensor Network (USN) system based on on-line and real-time monitoring system is being developed by the authors' research group. In this study, real-time pipeline health monitoring (PHM) methodology is presented based on electromechanical impedance methods using USN. Two types of damages including loosened bolts and notches are artificially inflicted on the pipeline structures, PZT and MFC sensors that have piezoelectric characteristics are employed to detect these damages. For objective evaluation of pipeline conditions, Damage metric such as Root Mean Square Deviation (RMSD) value was computed from the impedance signals to quantify the level of the damage. Optimal threshold levels for decision making are estimated by generalized extreme value(GEV) based statistical method. Throughout a series of experimental studies, it was reviewed the effectiveness and robustness of proposed PHM system.

• 한국균학회소식:학술대회논문집
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• 2018.05a
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• pp.13-13
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• 2018

Alternaria is a ubiquitous fungal genus, widely distributed in the environment and a range of different habitats. It includes both plant pathogenic and saprophytic species, which can affect crops in the field or cause post-harvest spoilage of plant fruits and kernels. Numerous Alternaria species cause damage to agricultural products including cereal grains, fruits and vegetables, and are responsible for severe economic losses worldwide. Most Alternaria species have the ability to produce a variety of secondary metabolites, which may play important roles in plant pathology as well as food quality and safety. Alternariol (AOH), alternariol monomethyl ether (AME), tenuazonic acid (TeA), tentoxin (TEN) and altenuene (ALT) are considered the main Alternaria compounds thought to pose a risk to human health. However, food-borne Alternaria species are able to produce many additional metabolites, whose toxicity has been tested incompletely or not tested at all. Both alternariols are mutagenic and their presence in cereal grain has been associated with high levels of human esophageal cancer in China. TeA exerts cytotoxic and phytotoxic properties, and is acutely toxic in different animal species, causing hemorrhages in several organs. The possible involvement of TA in the etiology of onyalai, a human hematological disorder occurring in Africa, has been suggested. Altertoxins (ALXs) have been found to be more potent mutagens and acutely toxic to mice than AOH and AME. Other metabolites, such as TEN, are reported to be phytotoxins, and their toxicity on animals has not been demonstrated up to now. Vegetable foods infected by Alternaria rot are obviously not suitable for consumption. Thus, whole fresh fruits are not believed to contribute significantly with Alternaria toxins to human exposure. However, processed vegetable products may introduce considerable amounts of these toxins to the human diet if decayed or moldy fruit is not removed before processing. The taxonomy of the genus is not well defined yet, which makes it difficult to establish an accurate relationship between the contaminant species and their associated mycotoxins. Great efforts have been made to organize taxa into subgeneric taxonomic levels, especially for the small-spored, food associated species, which are closely related and constitute the most relevant food pathogens from this genus. Several crops of agricultural value are susceptible to infection by different Alternaria species and can contribute to the entry of Alternaria mycotoxins in the food chain. The distribution of Alternaria species was studied in different commodities grown in Argentina. These food populations were characterized through a polyphasic approach, with special interest in their secondary metabolite profiles, to understand their full chemical potential. Alternaria species associated with tomato, bell pepper, blueberry, apples and wheat cultivated in Argentina showed a surprisingly high metabolomic and mycotoxigenic potential. The natural occurrence of Alternaria toxins in these foods was also investigated. The results here presented will provide background for discussion on regulations for Alternaria toxins in foods.

• Journal of Periodontal and Implant Science
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• v.30 no.4
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• pp.895-913
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• 2000

It is becoming increasingly clear that human gingival fibroblasts(HGF) may play a role in regulating immune responsiveness in inflammatory periodontal lesions. Stimulation of HGF with locally-secreted T cell cytokine $IFN_{\gamma}$ induces human leukocyte antigen class II(HLA II) expression on HGF, which is one of the characteristic feature of professional antigen presenting cells(pAPC). However, $IFN_{\gamma}$-treated HGF and other nonprofessional antigen presenting cells(npAPC) are known to be ineffective or less effective antigen presenter to resting T cells. This study, therefore, was undertaken in an effort to elucidate the differences in expression of cell surface molecules between npAPC in periodontal tissues, such as HGF and periodontal ligament fibroblasts(PDLF), and pAPC such as monocytes/macrophages. Using flow cytometry, the levels of cell surface expression of HLA-D, ICAM-1, LFA-3, and B7-1, which are involved in antigen presentation, were determined in HGF, PDLF and human myelomonocytic cell line THP-1. $IFN_{\gamma}$ clearly induced HLA-D expression on both of fibroblasts and monocytes dose dependently. However, expression level on monocytes were 4 to 5 times higher than that on fibroblasts, and induction rate was faster in monocytes than in fibroblasts. The levels of ICAM-1 expression on fibroblasts and monocytes were enhanced by $IFN_{\gamma}$ in a dose dependent manner. On the other hand, the expression of LFA-3 molecule, which could be detected in fibroblasts and monocytes without cytokine stimulation, was no more enhanced by addition of $IFN_{\gamma}$. B7-1, important costimulatory molecule in T cell activation and proliferation, was not detected on both of fibroblasts and monocytes even when stimulated with $IFN_{\gamma}$, except on monocytes fully differentiated by pretreatment of PMA and treated by $IFN_{\gamma}$. These results suggest that delayed expression of HLA-D and absence of B7-1 on $IFN_{\gamma}$ - treated fibroblasts may at least in part be involved in the ineffectiveness of fibroblasts as primary APC. And it is postulated that although periodontal fibroblasts may not serve as primary APC in normal periodontium, sustained expression of HLA II on ubiquitous fibroblasts in inflammatory lesions may perpetuate immune responses and produce chronic inflammation and tissue injury.