• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.9
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• pp.4446-4462
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• 2019

In this paper, we focus on interference cancellation for three-hop cognitive radio networks (CRNs) over Rayleigh fading channels. In CRNs, secondary users (SUs) are allowed to opportunistically utilize the licensed spectrum during the idle time of primary users (PUs) to achieve spectrum sharing. However, the SUs maybe power constrained to avoid interference and cover a very short transmission range. We here propose an interference cancellation scheme (ICS) for three-hop CRNs to prolong the transmission range of SUs and improve their transmission efficiency. In the proposed scheme, a flexible transmission protocol is adopted to cancel the interference at both secondary relays and destinations at the same time. And a closed-form expression for the secondary outage probability over Rayleigh fading channels is derived to measure the system performance. Simulation results show that the proposed scheme can significantly reduce the secondary outage probability and increase the secondary diversity in comparison with the traditional cases.

• Journal of IKEEE
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• v.24 no.4
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• pp.1017-1021
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• 2020

In the V2X communications, each vehicle periodically broadcasts a message, called a beacon, so that its neighbor vehicles can accurately predict the near-future positions of the sending vehicle. In particular, the mobility-adaptive beacon broadcast (MAB2) scheme keeps the tracking error of a sending vehicle below a fixed threshold within a few consecutive beacon losses. In this paper, we present a random-early beacon broadcast (REB2) scheme that addresses the beacon aging problem of the MAB2 scheme. The simulation results show that, for a neighbor vehicle within 100 m distance, the tracking failure probability of REB2 scheme can be reduced to less than 1/10 of that of MAB2 scheme.

• Journal of Dental Anesthesia and Pain Medicine
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• v.21 no.3
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• pp.219-226
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• 2021

Background: Patients with disabilities often require general anesthesia for dental treatment because of their cooperative or physical problems. Since most patients with disabilities take central nervous system drugs, the management of recovery status is important because of drug interactions with anesthetics. Methods: The anesthesia records of patients under general anesthesia for dental treatment were reviewed, and data were collected. Healthy patients under general anesthesia for dental phobia or severe gagging reflex were designated as the control group. Patients with disabilities were divided into two groups: those not taking any medication and those taking antiepileptic medications. The awakening time was evaluated in 354 patients who underwent dental treatment under general anesthesia (92 healthy patients, 183 patients with disabilities, and 79 patients with disabilities taking an antiepileptic drug). Based on the data recorded in anesthesia records, the awakening time was calculated, and statistical processes were used to determine the factors affecting awakening time. Results: Significant differences in awakening time were found among the three groups. The awakening time from anesthesia in patients with disabilities (13.09 ± 5.83 min) (P < 0.0001) and patients taking antiepileptic drugs (18.18 ± 7.81 min) (P < 0.0001) were significantly longer than in healthy patients (10.29 ± 4.87 min). Conclusion: The awakening time from general anesthesia is affected by the disability status and use of antiepileptic drugs.

• Journal of Microbiology and Biotechnology
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• v.32 no.5
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• pp.602-611
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• 2022

The persistence of pathogenic Escherichia coli under acidic conditions poses a serious risk to food safety, especially in acidic foods such as kimchi. To identify the bacterial factors required for acid resistance, transcriptomic analysis was conducted on an acid-resistant enterotoxigenic E. coli strain and the genes with significant changes in their expression under acidic pH were selected as putative resistance factors against acid stress. These genes included those associated with a glutamate-dependent acid resistance (GDAR) system and copper resistance. E. coli strains lacking GadA, GadB, or YbaST, the components of the GDAR system, exhibited significantly attenuated growth and survival under acidic stress conditions. Accordantly, the inhibition of the GDAR system by 3-mercaptopropionic acid and aminooxyacetic acid abolished bacterial adaptation and survival under acidic conditions, indicating the indispensable role of a GDAR system in acid resistance. Intriguingly, the lack of cueR encoding a transcriptional regulator for copper resistance genes markedly impaired bacterial resistance to acid stress as well as copper. Conversely, the absence of YbaST severely compromised bacterial resistance against copper, suggesting an interplay between acid and copper resistance. These results suggest that a GDAR system can be a promising target for developing control measures to prevent E. coli resistance to acid and copper treatments.

• Food Science of Animal Resources
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• v.43 no.3
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• pp.540-551
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• 2023

Milk protein concentrate (MPC) is widely used to enhance the stability and texture of fermented dairy products. However, most research has focused on yogurt products, and the effects of MPC on sour cream characteristics remain unknown. Therefore, we investigated the effects of different MPC levels (0%, 1%, 2%, and 3% w/w) on the rheological, physicochemical, microbiological, and aroma characteristics of sour creams in this study. We found that MPC supplementation stimulated the growth of lactic acid bacteria (LAB) in sour creams, resulting in higher acidity than that in the control sample due to the lactic acid produced by LAB. Three aroma compounds, acetaldehyde, diacetyl, and acetoin, were detected in all sour cream samples. All sour creams showed shear-thinning behavior (n=0.41-0.50), and the addition of MPC led to an increase in the rheological parameters (η_a,50, K, G', and G"). In particular, sour cream with 3% MPC showed the best elastic property owing to the interaction between denatured whey protein and caseins. In addition, these protein interactions resulted in the formation of a gel network, which enhanced the water-holding capacity and improved the whey separation. These findings revealed that MPC can be used as a supplementary protein to improve the rheological and physicochemical characteristics of sour cream.

• Proceedings of the Korea Information Processing Society Conference
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• 2009.11a
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• pp.181-182
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• 2009

본 논문에서는 IEEE 802.15.4a 근거리 무선 네트워크를 이용하여 다중 이동 로봇을 사용자 휴대 단말을 이용하여 실시간으로 편리하게 제어하기 위한 플랫폼을 설계하고 그 기본기능을 검증한다. 제안한 원격제어 플랫폼은 IEEE 802.15.4a 기반의 최초의 원격제어 플랫폼으로서 그 의의를 가지며, 자동 스페이싱(auto-spacing)을 기반한 다중 로봇 그룹이동과 IEEE 802.15.4a의 거리측정 기능과 초음파 및 자이로센서를 이용한 상대각측정 기능을 이용한 협동위치인식(cooperative localization) 기능을 제공하는데 기존 기법들과의 차별성이 존재한다.

• Asia Marketing Journal
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• v.12 no.2
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• pp.135-154
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• 2010

This paper considers a duopoly where switching costs exist. The analysis proves that temporal price reductions can be pure strategy equilibrium where firms earn more profit than in a regular price strategy. Greater profits result from price discrimination in temporal price reductions. The equilibrium is contrasted with previous studies, which explain temporal price reductions as a result of mixed strategy. In a given model with an assumption about forming switching cost, firms can control their range of loyal consumers by properly setting their regular and promotional prices. The model shows that temporal price reduction tends to raise the regular price and decrease the range of loyal consumers.

• Journal of Environmental Science International
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• v.32 no.10
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• pp.741-744
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• 2023

This study focused on high school laboratory research and the main purpose was to develop alternative additives for livestock waste and ammonia volatilization methods with high school students as participants and to provide information to business owners based on the results. Compared to the control groups, The bentonite and illite treatment groups had similar ammonia volatilization, pH, EC, and total nitrogen content. In particular, the alum and aluminum chloride mixed treatment group showed low pH and ammonia volatilization, and high EC and total nitrogen content for poultry litter. As a result, when focusing on high school laboratory research, the alum and aluminum chloride mixed agent treatment fulfilled its role as an alternative additive for ammonia reduction. In addition, this approach can be suggested as a method to solve difficulties in adapting to the field through a practical cooperative relationship with livestock farms.

• Korean Journal of Radiology
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• v.22 no.6
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• pp.944-950
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• 2021

Objective: To demonstrate the feasibility of percutaneous microwave ablation in desmoid fibromatosis with respect to tumor volume control and improvement in the quality of life. Materials and Methods: Twelve microwave ablations were performed in 9 patients with a histological diagnosis of desmoid fibromatosis between January 2010 and January 2019. The study population included 6 female and 3 male, with an age range of 21-76 years (mean = 46.6 years; standard deviation [SD] = 19.3 years). The mean major axis of the tumors was 10.9 cm (SD = 5.2 cm) and mean lesion volume was 212.7 cm³ (SD = 213 cm³). Their anatomical distribution was as follows: 3 lesions in the thigh, 2 in the gluteus, 2 in the leg and 2 in the periscapular region. We evaluated the reduction in tumor volume and improvement in the quality of life based on the Eastern Cooperative Oncology Group (ECOG) scale. Results: An average tumor volume reduction of 70.4% (SD = 24.9) was achieved, while the quality of life (ECOG scale) improved in 88.9% of patients. Conclusion: Percutaneous microwave ablation may potentially be a safe, effective, and promising technique for controlling tumor volume and improving the quality of life in patients with desmoid fibromatosis.

• Journal of Korea Soil Environment Society
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• v.4 no.3
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• pp.57-65
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• 1999

Generation of gaseous ammonia has been a major problem in composting facilities. Microbial inocula. KMT-199(brand name: CompoBac$^{TM}$). was developed in INBI0NET CORPORATION and tested in the field for its ammonia reducing capability. When KMT-199 was applied. a ten-fold increase of mesophilic and thermophilic microorganisms was observed during the early stage of composting process. Also. the temperature and pH of early stage compost increased at a higher rate when compared to control. KMT-199 treated compost reached highest temperature of $75^{\circ}C$at day 9, indicating treatment could shift the maximum composting temperature to 3 days earlier The highest temperature also reached $3^{\circ}C$ higher than the control. The pH of compost gradually increased during composting. KMT-199 treated compost reached a plateau of pH 9.32 at day 15 after treatment, and then slowly decreased thereafter. On the other hand. pH of the control steadily increased until day 38 of composting. 29% reduction of gaseous ammonia generation during composting was observed compared to that of the control. KMT-199 amended compost resulted in a higher germination rate of radish seeds than the control. These results indicate that application of microbial inocula facilitates degradation of organic materials, including ammonia during the composting process.