• Microbiology and Biotechnology Letters
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• v.42 no.3
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• pp.238-248
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• 2014

The metalloid arsenic (Z = 33) is considered to be a significant potential threat to human health due to its ubiquity and toxicity, even in rural regions. In this study a rural region contaminated with arsenic, located at longitude $85^{\circ}$ 32'E and latitude $25^{\circ}$ 11'N, was initially examined. Arsenic tolerant bacteria from the rhizosphere of Amaranthas viridis were found and identified as Bacillus licheniformis through 16S rRNA gene sequencing. The potential for the uptake and removal of arsenic at 3, 6 and 9 mM [As(V)], and 2, 4 and 6 mM [As(III)], and for the reduction of the above concentrations of As(V) to As(III) by the Bacillus licheniformis were then assessed. The minimal inhibitory concentrations (MIC) for As(V) and As(III) was determined to be 10 and 7 mM, respectively. At 3 mM 100% As(V) was uptaken by the bacteria with the liberation of 42% As(III) into the medium, whereas at 6 mM As(V), 76% AS(V) was removed from the media and 56% was reduced to As(III). At 2 mM As(III), the bacteria consumed 100%, whereas at 6 mM, the As(III) consumption was only 40%. The role of pH was significant for the speciation, availability and toxicity of the arsenic, which was measured as the variation in growth, uptake and content of cell protein. Both As(V) and As(III) were most toxic at around a neutral pH, whereas both acidic and basic pH favored growth, but at variable levels. Contrary to many reports, the total cell protein content in the bacteria was enhanced by both As(V) and As(III) stress.

• International Journal of Control, Automation, and Systems
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• v.6 no.2
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• pp.186-193
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• 2008

The Internet's low cost and ubiquity present an attractive option for real-time distributed control of processes on the factory floor. When integrated with the Internet, the LonWorks open control network can give ubiquitous accessibility with the distributed control nature of information on the factory floor. One of the most important points in real-time distributed control of processes is timely response. There are many processes on the factory floor that require timely response. However, the uncertain time delay inherent in the network makes it difficult to guarantee timely response in many cases. Especially, the transmission characteristics of the LonWorks/IP network show a highly stochastic nature. Therefore, the time delay problem has to be resolved to achieve high performance and quality of the real-time distributed control of the process in the LonWorks/IP Virtual Device Network (VDN). It should be properly predicted and compensated. In this paper, a new distributed control scheme that can compensate for the effects of the time delay in the network is proposed. It is based on the PID controller augmented with the Smith predictor and disturbance observer. Designing methods for output feedback filter and disturbance observer are also proposed. Tracking position control experiment of a geared DC Servo motor is performed using the proposed control method. The performance of the proposed controller is compared with that of the Internal Model Controller (IMC) with the Smith predictor. The result shows that the performance is improved and guaranteed by augmenting a PID controller with both the Smith predictor and disturbance observer under the stochastic time delay in the LonWorks/IP VDN.

• Korean journal of communication and information
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• v.18
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• pp.131-164
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• 2002

Despite the ubiquity of telephone, the medium has received far less scholarly attention than it should deserve. This study begin with the purpose of fair appraisement of telephone in Korean social communication. To accomplish this purpose, the gratification obtained from telephone, the appropriateness of it as interpersonal communication medium and communication network through telephone were studied. The related raw data were collected from on-line survey process, and statistically analyzed. The result showed sociability, information, transaction, entertainment, emergency, and reassurance are gratifications obtained from telephone use. Younger persons tend to have more positive attitude to mobile phone as interpersonal communication medium. Particularly when the seniors are interpersonal communication partner and impending task is advice or request, younger persons tend to perceive mobile phone more appropriate than the elder persons do. And mobile phone deepens 'communication endogamy' of our society, especially in the youth. Thus, it is plausible to predict that mobile phone will be more important in social communication of our society when the youth become the mainstream of our society.

• Journal of Digital Convergence
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• v.11 no.1
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• pp.153-163
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• 2013

The application demand has been rapidly increasing along the growth of smart devices. Companies actively use the application as marketing tools. In particular, fashion businesses expect the improvement of customer loyalty and brand image by using the applications as the communication channel with consumers. This paper investigated the relationship between mobile shopping motives and mobile shopping acceptance. Influence of such variables on perceived importance of various fashion application attributes was also accessed. Data from male and female respondents were analyzed for the empirical study. Results indicated that mobile shopping motives were classified into convenience, ubiquity, impulsiveness and economic motives. Fashion application attribute was classified into contents, continuous management, design/visibility, downloading and community. Mobile shopping motives had significant correlation with fashion application acceptance. Shopping motives and fashion application acceptance had significant impacts on perceived importance of various fashion application attributes.

• Korean journal of communication and information
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• v.21
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• pp.87-113
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• 2003

Despite the ubiquity of mobile phone, the medium has received far less scholarly attention than it should deserve. This study begin with the purpose of fair repositioning of mobile phone in Korean interpersonal communication. To accomplish this purpose, We examined the effect of communication values on perception of mobile phone as interpersonal communication medium, such as the appropriateness and effectiveness of mobile phone. The related raw data were collected from on-line survey process, and statistically analyzed. The result showed that the more effect the traditional communication values of our society have on the perception of mobile phone, the older users are. And Younger generations tend to have more positive attitude to mobile phone as interpersonal communication medium. Particularly when the seniors are interpersonal communication partner and impending task is advice or request, younger persons tend to perceive mobile phone more appropriate and effective than the elder persons do. Thus, it is plausible to predict that relative position of mobile phone will be gradually more important in Koreans' social communication when the younger generation become the mainstream of our society.

• International Journal of Highway Engineering
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• v.15 no.5
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• pp.167-176
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• 2013

PURPOSES : Lately, a traffic information market has been developed with a rapid speed owing to information and communications. In this situation, a study on the use intention and the satisfaction of mobile transportation information applications of users will be diverse implications and a strategic foundation to local governments and transportation information related enterprises that should provide satisfactory info as public goods to much more users. METHODS : Going along with the flow, this study establishes features of the mobile transportation information applications aiming to the users and analyzes empirical causality for effects of the use intension and the satisfaction. Through this study's analysis, targeting users having experienced transportation information applications among smart phone users, a survey was conducted and characteristics of the transportation information applications were lighted and the effects of the use intention and the satisfaction were analyzed using a technology acceptance model. RESULTS : The analysis result was that Accuracy, Riskiness, Ubiquity and Interactivity as all attributes of transportation information applications have a significant effect on Perceived usefulness and Perceived Ease of Use respectively. The Perceived usefulness and Perceived Ease of Use have affected significantly users' satisfaction respectively, so consequentially this shows effect relationship leading to reuse intention. CONCLUSIONS : The Perceived usefulness and Perceived Ease of Use all for the transportation information applications were shown to influence significantly on the satisfaction. With this kind of result, if users obtain positive outcomes such as travel time reduction or effective roles on their tasks through the transportation information applications, they feel the satisfaction for using and eventually these affect positively to the reuse intention of those transportation information applications.

• Journal of Internet of Things and Convergence
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• v.8 no.1
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• pp.79-85
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• 2022

Internet of Things (IoT) connects devices with various platforms, computing power, and functions. Due to the diversity of networks and the ubiquity of IoT devices, demands for security and privacy are increasing. Therefore, cryptographic mechanisms must be strong enough to meet these increased requirements, while at the same time effective enough to be implemented in devices with long-range specifications. In this paper, we present the performance and memory limitations of modern cryptographic primitives and schemes for different types of devices that can be used in IoT. In addition, detailed performance evaluation of the performance of the most commonly used encryption algorithms in low-spec devices frequently used in IoT networks is performed. To provide data protection, the binary ring uses encryption asymmetric fully homomorphic encryption and symmetric encryption AES 128-bit. As a result of the experiment, it can be seen that the IoT device had sufficient performance to implement a symmetric encryption, but the performance deteriorated in the asymmetric encryption implementation.

• Journal of Digital Convergence
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• v.20 no.3
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• pp.169-180
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• 2022

As people spend more time indoors due to the COVID-19 pandemic situation, content consumption is increasing, leading to the rapid demand for Over The Top(OTT) services. Thus, this study attempted to verify impacts of OTT traits on the value, satisfaction, and continuous use intention perceived by users. Through the survey, 437 responses were collected, and analysis was conducted using AMOS 26.0. Results found that the traits of OTT service had a positive effect on perceived value that had a positive effect on user satisfaction and continuous use intention. User satisfaction was also found to have a positive effect on the intention to continue using OTT services. Moreover, hedonic innovation moderated the relationships between OTT traits and perceived value with exception of ubiquity. The findings provide valuable information for OTT service providers in understading users' behaviors.

• Journal of Electrochemical Science and Technology
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• v.15 no.1
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• pp.198-206
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• 2024

Given the high theoretical capacity (1,675 mAh g^-1) and the inherent affordability and ubiquity of elemental sulfur, it stands out as a prominent cathode material for advanced lithium metal batteries. Traditionally, sulfur was sequestered within conductive porous carbons, rooted in the understanding that their inherent conductivity could offset sulfur's non-conductive nature. This study, however, pivots toward a transformative approach by utilizing diatom shell (DS, diatomite)-a naturally abundant and economically viable siliceous mineral-as a sulfur host. This approach enabled the development of a sulfurlayered diatomite/S composite (DS/S) for cathodic applications. Even in the face of the insulating nature of both diatomite and sulfur, the DS/S composite displayed vigorous participation in the electrochemical conversion process. Furthermore, this composite substantially curbed the loss of soluble polysulfides and minimized structural wear during cycling. As a testament to its efficacy, our Li-S battery, integrating this composite, exhibited an excellent cycling performance: a specific capacity of 732 mAh g^-1 after 100 cycles and a robust 77% capacity retention. These findings challenge the erstwhile conviction of requiring a conductive host for sulfur. Owing to diatomite's hierarchical porous architecture, eco-friendliness, and accessibility, the DS/S electrode boasts optimal sulfur utilization, elevated specific capacity, enhanced rate capabilities at intensified C rates, and steadfast cycling stability that underscore its vast commercial promise.

• Information Systems Review
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• v.19 no.1
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• pp.49-74
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• 2017

The development of smart devices has affected employees' working environments and their lives. However, using smart devices is causing employees to experience technostress. This study aims to investigate the effects of technostress in using smart devices on usage intention in an organization. Moreover, the study investigates the effect of employees' stress-coping methods on the intention to use smart devices. This study posits familiarity, use innovativeness, role ambiguity, system vulnerability, technological limitation, and ubiquity as the antecedents of technostress. Data collected from 317 users who have experience in using smart devices in organizations are empirically tested against a research model using the PLS graph. Analysis results show that role ambiguity, system vulnerability, and technological limitation significantly influence technostress. Moreover, users take up emotion-focused coping behaviors because of technostress. Emotion-focused coping behaviors affect usage intention in organizations. However, technostress and problem-focused coping behaviors do not directly affect usage intention in organizations.