• International Journal of Computer Science & Network Security
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• v.22 no.10
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• pp.191-200
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• 2022

Constrained Application Protocol (CoAP) is a standardized protocol by the Internet Engineering Task Force (IETF) for the Internet of things (IoT). IoT devices have limited computation power, memory, and connectivity capabilities. One of the significant problems in IoT networks is congestion control. The CoAP standard has an exponential backoff congestion control mechanism, which may not be adequate for all IoT applications. Each IoT application would have different characteristics, requiring a novel algorithm to handle congestion in the IoT network. Unnecessary retransmissions, and packet collisions, caused due to lossy links and higher packet error rates, lead to congestion in the IoT network. This paper presents an adaptive congestion control protocol for CoAP, Adaptive Congestion Control with a Backoff algorithm (ACCB). AACB is an extension to our earlier protocol AdCoCoA. The proposed algorithm estimates RTT, RTTVAR, and RTO using dynamic factors instead of fixed values. Also, the backoff mechanism has dynamic factors to estimate the RTO value on retransmissions. This dynamic adaptation helps to improve CoAP performance and reduce retransmissions. The results show ACCB has significantly higher goodput (49.5%, 436.5%, 312.7%), packet delivery ratio (10.1%, 56%, 23.3%), and transmission rate (37.7%, 265%, 175.3%); compare to CoAP, CoCoA+ and AdCoCoA respectively in linear scenario. The results show ACCB has significantly higher goodput (60.5%, 482%,202.1%), packet delivery ratio (7.6%, 60.6%, 26%), and transmission rate (40.9%, 284%, 146.45%); compare to CoAP, CoCoA+ and AdCoCoA respectively in random walk scenario. ACCB has similar retransmission index compare to CoAp, CoCoA+ and AdCoCoA respectively in both the scenarios.

• Toxicological Research
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• v.32 no.2
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• pp.149-158
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• 2016

Atopic dermatitis (AD) is a chronic inflammatory skin disease with a complex etiology that encompasses immunologic responses. AD is frequently associated with elevated immunoglobulin (Ig) E levels, and common environmental factors contribute to its pathogenesis. Several recent studies have documented the role of specific lactic acid bacteria in the treatment and prevention of AD in humans and mice. In this study, the efficacy of Duolac ATP, a probiotic preparation, was determined in a mouse model with AD-like skin lesions. Alterations in the cytokine levels and histological staining suggested the alleviation of AD. The in vivo test showed that T helper (Th)2 cytokines, IgE, interleukin (IL)-4, and IL-5, were significantly downregulated, whereas Th1 cytokines, IL-12p40 and interferon (IFN)-${\gamma}$, were upregulated in all groups of mice treated with Duolac ATP compared to that observed in the group of mice treated with 1-chloro-2,4-dinitrobenzene (DNCB) alone. Moreover, the scratch score decreased in all mice treated with Duolac ATP. Staining of the dorsal area of the mice in each group with hematoxylin and eosin and toluidine blue further confirmed the alleviation of AD in mice orally treated with Duolac ATP. These results suggest that Duolac ATP inhibits the development of AD-like skin lesions in NC/Nga mice by suppressing the Th2 cell response and increasing the Th1 cell response. Thus, Duolac ATP is beneficial and effective for the treatment of AD-like skin lesions.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.65 no.4
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• pp.508-517
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• 2020

This study aimed to determine the minimum period of aeration treatment of co-digestate to develop it as liquid fertilizer and the chemical changes that occur in the aerobic liquefying process. The co-digestates were divided into three types depending on their additives: swine slurry anaerobic digestate (SS AD), swine slurry 70% + cow slurry 30% anaerobic digestate (SS + CS AD), and swine slurry 70% + apple pomace 30% anaerobic digestate (SS + AP AD). The pH of all co-digestates increased rapidly after 3 days of aerobic treatment, but had slightly decreased in SS AD after 9 days and in SS + CS AD and SS + AP AD after 15 days. All co-digestates showed a strongly reduced pH between 27 and 36 days of aeration treatment. SS AD had lower pH value, dissolved oxygen (DO), NH₄-N, and NO₃-N content under aerobic conditions than other co-digestates. To assess the fully decomposed liquid fertilizer, a germination test was performed on the undiluted and diluted co-digestate using the liquid fertilizer germination index (LFGI) method. The relative germination ratio, relative root elongation, and germination index of SS AD were higher than those of the others. When the LFGI method was used for the germination test, all co-digestates showed an appropriate germination index of 70 after 60 days of aeration treatment. Thus, we suggest that the minimum period of aeration treatment for co-digestates might be 60 days to develop the fully decomposed liquid fertilizer.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.151.1-151.1
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• 2003

Polyunsaturated fatty acids (PUFAs) play many important physiological roles on cellular process through the regulations of intracellular signaling. Recent clinical studies suggest that PUFAs such as n-3 fatty acids (docosahexaenoic acid, 22:6 and a-lnolenic acid, 18:3) may reduce the risk of incident Alzheimer's disease (AD). And also the reports regarding the decrease of n-3 fatty acids in AD brain support the correlation between PUFAs and AD. AD is a neurodegenerative disorder with pathological hallmarks of amyloid plaques and neurofibrillary tangles. (omitted)

• New & Renewable Energy
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• v.4 no.2
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• pp.21-30
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• 2008

Anaerobic digestion (AD) is the most promising method of treating and recycling of different organic wastes, such as OFMSW, household wastes, animal manure, agro-industrial wastes, industrial organic wastes and sewage sludge. During AD, i.e. degradation in the absence of oxygen, organic material is decomposed by anaerobes forming degestates such as an excellent fertilizer and biogas, a mixture of carbon dioxide and methane. AD has been one of the leading technologies that can make a large contribution to producing renewable energy and to reducing $CO_2$ and other GHG emission, it is becoming a key method for both waste treatment and recovery of a renewable fuel and other valuable co-products. A classification of the basic AD technologies for the production of biogas can be made according to the dry matter of biowaste and digestion temperature, which divide the AD process in wet and dry, mesophilic and thermophilic. The biogas produced from AD plant can be utilized as an alternative energy source, for lighting and cooking in case of small-scale, for CHP and vehicle fuel or fuel in industrials in case of large-scale. This paper provides an overview of the status of biogas production and utilization technologies.

• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.202-205
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• 2008

Anaerobic digestion(AD) is the most promising method of treating and recycling of different organic wastes, such as OFMSW, household wastes, animal manure, agro-industrial wastes, industrial organic wastes and sewage sludge. During AD, i.e. degradation in the absence of oxygen, organic material is decomposed by anaerobes forming degestates such as an excellent fertilizer and biogas, a mixture of carbon dioxide and methane. AD has been one of the leading technologies that can make a large contribution to producing renewable energy and to reducing $CO_2$ and other GHG emission, it is becoming a key method for both waste treatment and recovery of a renewable fuel and other valuable co-products. A classification of the basic AD technologies for the production of biogas can be made according to the dry matter of biowaste and digestion temperature, which divide the AD process in wet and dry, mesophilic and thermophilic. The biogas produced from AD plant can be utilized as an alternative energy source, for lighting and cooking in case of small-scale, for CHP and vehicle fuel or fuel in industrials in case of large-scale. This paper provides an overview of the status of biogas production and utilization technologies.

• Journal of Periodontal and Implant Science
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• v.39 no.sup2
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• pp.279-286
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• 2009

Purpose: Gene therapy (ex vivo) has recently been used as a means of delivering bone morphogenetic proteins (BMPs) to sites of tissue regeneration. In the present study, we investigated the effect of co-transduction of adenoviruses expressing BMP-2 and BMP-7 on osteogenesisof C2C12 cells in vitro. Methods: A replication-defective human adenovirus 5 (Ad5) containing a cDNA for BMPs in the E1 region of the virus (Ad5BMP-2 and Ad5BMP-7) was constructed by in vivo homologous recombination. Functional activity of Ad5BMP-2 and Ad5BMP-7 were evaluated in mouse stromal cells (W20-17cells). C2C12 cells are transduced with various MOI (multiplicity of infection) of Ad5BMP-2 and Ad5BMP-7 to assess most effective and stable titer. Based on this result, C2C12 cells were transduced with Ad5BMP-2 and Ad5BMP-7 alone or by combination. BMPs expression, alkaline phosphatase (ALPase) activity, cell proliferation, and mineralization were assessed. Results: Ad5BMP-2 and Ad5BMP-7 are successfully transduced to W20-17 cells, and secreted BMPs stimulated cell differentiation. Also, C2C12 cells transduced with Ad5BMPs showed expression of BMPs and increased ALPaseactivity. In all groups, cell proliferation was observed over times. At 7days, cells co-transduced with Ad5BMP-2 and Ad5BMP-7 showed lower proliferation than the others. C2C12 cells co-transduced with Ad5BMP-2 and Ad5BMP-7 had greater ALPaseactivity than that would be predicted if effect of individual Ad5BMPs were additive. Little mineralized nodule formation was detected in cells transduced with individual Ad5BMPs. In contrast, Ad5BMP-2 and Ad5BMP-7 combination stimulated mineralization after culturing for 10 days in mineralizing medium. Conclusions: Present study demonstrated that adenoviruses expressing BMPs gene successfully produced BMPs protein and these BMPs stimulated cells to be differentiated into osteoblastic cells. In addition, the osteogenic activity of Ad5BMPs can be synergistically increased by co-transduction of cells with Ad5BMP-2 and Ad5BMP-7.

• IMMUNE NETWORK
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• v.21 no.4
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• pp.29.1-29.9
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• 2021

There are limited data directly comparing humoral and T cell responses to the ChAdOx1 nCoV-19 and BNT162b2 vaccines. We compared Ab and T cell responses after first doses of ChAdOx1 nCoV-19 vs. BNT162b2 vaccines. We enrolled healthcare workers who received ChAdOx1 nCoV-19 or BNT162b2 vaccine in Seoul, Korea. Anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) S1 protein-specific IgG Abs (S1-IgG), neutralizing Abs (NT Abs), and SARS-CoV-2-specific T cell response were evaluated before vaccination and at 1-wk intervals for 3 wks after vaccination. A total of 76 persons, comprising 40 injected with the ChAdOx1 vaccine and 36 injected with the BNT162b2 vaccine, participated in this study. At 3 wks after vaccination, the mean levels (±SD) of S1-IgG and NT Abs in the BNT162b2 participants were significantly higher than in the ChAdOx1 participants (S1-IgG, 14.03±7.20 vs. 6.28±8.87, p<0.0001; NT Ab, 183.1±155.6 vs. 116.6±116.2, p=0.035), respectively. However, the mean values of the T cell responses in the 2 groups were comparable after 2 wks. The humoral immune response after the 1st dose of BNT162b2 developed faster and was stronger than after the 1st dose of ChAdOx1. However, the T cell responses to BNT162b2 and ChAdOx1 were similar.

• Journal of KIISE:Information Networking
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• v.37 no.2
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• pp.122-134
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• 2010

With the rapidly increasing demand of traffic applications, the need to support seamless and robust multimedia services in the Vehicular Ad hoc Network is growing. Fast handover for the MIPv6 (FMIPv6) developed to solve the MIPv6's problem as well as Mobile IPv6 (MIPv6) for basic mobility protocol have been developed to support seamless handover in mobile environment. However, MIPv6 and FMIPv6 are useless for Quality-of-Service (QoS) services such as multimedia applications due to the long handover latency and the packet loss problem. In this paper, we propose a seamless and robust handover scheme that supports multimedia services in Vehicular Ad hoc Network using oCoA and background DAD. Through performance evaluation, we show that the proposed scheme is more proper for Vehicular Ad hoc Network than other schemes.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2017.10a
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• pp.607-608
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• 2017

이동 Ad-hoc 무선망은 고정 라우터나 호스트, 무선 기지국에 관계없이 순수하게 무선기반의 인프라 구조로 구성된 망이다. 기존의 무선망 인프라는 기반 구축 비용이 많이 들고 기반구조가 파괴되었을 때 서비스 제공이 불가능한 단점이 있다. Ad-hoc 무선망은 이러한 단점을 보안하기 위해 라우팅 알고리즘을 구현하여 기존의 통신망보다 Ad-hoc 무선망을 이용하면 지진으로 인한 유 무선망의 통화단절 등을 막을 수 있고, 이동전화 품질서비스, 저렴한 가격, 떨어져 있는 동일 사업장내에서 무료 통화가 가능하여 이동통신 사업자에게 통신료를 지불할 필요가 없다. 본고에서는 이를 실현화 시킬 수 있는 알고리즘 개발과 시험을 통한 결과를 제시하고자 한다.