• Membrane and Water Treatment
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• v.8 no.6
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• pp.543-551
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• 2017

Membrane fouling in membrane bioreactor (MBR) remains a primary challenge for its wider application. The focus of this study to investigate the influence of iron distribution in activated sludge on gel layer fouling in MBR. Significant reduction in the transmembrane pressure (TMP) rise rates was observed in the presence of iron as result of retarding the gel layer formation time. The spatial distribution of iron had a significant impact on the stratification structure of extracellular polymeric substances (EPS) fractions, such as proteins (PN) and polysaccharides (PS). A mitigation of PN or PS from the supernatant to the EPS inner layers was observed in the presence of iron. Compared with the control reactor, the reduction in PN and PS of the supernatant and lower PN/PS rates of the LB-EPS were beneficial to decrease the membrane fouling potential during the gel layer formation. Consequently, the iron addition managed to control gel layer fouling could be a useful strategy in MBR.

• Journal of Korean Foot and Ankle Society
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• v.26 no.1
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• pp.48-53
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• 2022

The current SARS-CoV-2 coronavirus disease 2019 (COVID-19) pandemic has been a particular challenge for diabetes patients. Since these patients are at a higher risk of COVID-19, they have been prioritized for vaccination. In this report, we describe the case of a patient scheduled for diabetic foot amputation who received the first dose of ChAdOx1 nCov-19 vaccine and subsequently developed severe purpura in his genitalia and both of his hands and feet, accompanied by acute renal failure. The operation had to be postponed as severe limb purpura appeared just before the operation. With adequate management for acute renal failure and topical steroid application for the severe purpura lesions, a successful outcome could be obtained after the delayed first ray amputation. We recommend that COVID-19 vaccination should be carefully administered in patients with a diabetic foot requiring amputation.

• Archives of Reconstructive Microsurgery
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• v.22 no.2
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• pp.43-47
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• 2013

Purpose: Un-healing and centrally located defect on back area, it is sometimes a challenge for the reconstructive surgeon. Although skin grafts are considered as the first choice for reconstruction of large skin defect on the back region, it is not always helpful but vascularized flaps provide a superior functional and aesthetic outcome. The present study was designed to investigate the clinical anatomy of the lumbar artery perforator flap to reconstruct back ulcer. Materials and Methods: Clinical anatomy study was undertaken using computed tomographic angiographic analysis. We identified the courses of lumbar arteries and its perforators, measured pedicle length by layers. The location of the perforator vessel was charted against anatomical landmarks. Results: The pedicle lengths of the third and fourth lumbar artery perforator reached a mean of 27.8 mm and 37.1 mm respectively from superficial fascia to deep fascia. The fourth perforator was more laterally located than the third perforator and less than 1 cm above the iliac crest. A case in which the fourth lumbar artery perforator was used as flap pedicle is described. Conclusion: For the reconstruction of central defect on the back area, the lumbar artery perforator flap coverage may be a good alternative option. Computed tomographic angiography can easily identify the course and location of lumbar artery perforators and can be helpful to elevate the flap successfully.

• Asian Journal of Innovation and Policy
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• v.7 no.2
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• pp.310-337
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• 2018

Adoption of mobile learning (m-learning) is not new in Malaysian oil and gas industry, with heavy investment into research and development to train the workers. Nevertheless, the low application of learnt skills on the job remains an emergent research area where there is a missing link on the effects of m-learning and effective organisational learning and implication on its training transfer. The result of this quantitative research revealed that all variables in m-learning were found to have a positive relationship with the effective organisational learning, and there is evidence of training transfer as a mediator of the relationship between self-directed learning, training design, work environment and effective organisational learning. However, there were some discrepancies in the extend of training transfer between trainee characteristics and organisational learning. As such, some important issues emerged which challenge the importance of evaluating workers' readiness and transfer for a successful implementation of m-learning towards developing effective organisational learning.

• IEIE Transactions on Smart Processing and Computing
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• v.5 no.2
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• pp.94-99
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• 2016

Application layer attacks have for years posed an ever-serious threat to network security, since they always come after a technically legitimate connection has been established. In recent years, cyber criminals have turned to fully exploiting the web as a medium of communication to launch a variety of forbidden or illicit activities by spreading malicious automated software (auto-ware) such as adware, spyware, or bots. When this malicious auto-ware infects a network, it will act like a robot, mimic normal behavior of web access, and bypass the network firewall or intrusion detection system. Besides that, in a private and large network, with huge Hypertext Transfer Protocol (HTTP) traffic generated each day, communication behavior identification and classification of auto-ware is a challenge. In this paper, based on a previous study, analysis of auto-ware communication behavior, and with the addition of new features, a method for classification of HTTP auto-ware communication is proposed. For that, a Not Only Structured Query Language (NoSQL) database is applied to handle large volumes of unstructured HTTP requests captured every day. The method is tested with real HTTP traffic data collected through a proxy server of a private network, providing good results in the classification and detection of suspicious auto-ware web access.

• Journal of the Ergonomics Society of Korea
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• v.34 no.5
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• pp.531-540
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• 2015

Objective: The objective of this research is to investigate the fundamentals of human computer interaction for wearable computers and derive technology requirements. Background: A wearable computer can be worn anytime with the support of unrestricted communications and a variety of services which provide maximum capability of information use. Key challenges in developing such wearable computers are the level of comfort that users do not feel what they wear, and easy and intuitive user interface. The research presented in this paper examines user interfaces for wearable computers. Method: In this research, we have classified the wearable user interface technologies and analyzed the advantages and disadvantages from the user's point of view. Based on this analysis, we issued a user interface technology to conduct research and development for commercialization. Results: Technology requirements are drawn to make wearable computers commercialized. Conclusion: The user interface technology for wearable system must start from the understanding of the ergonomic aspects of the end user, because users wear the system on their body. Developers do not try to develop a state-of-the-art technology without the requirement analysis of the end users. If people do not use the technology, it can't survive in the market. Currently, there is no dominant wearable user interface in the world. So, this area might try a new challenge for the technology beyond the traditional interface paradigm through various approaches and attempts. Application: The findings in this study are expected to be used for designing user interface for wearable systems, such as digital clothes and fashion apparel.

• Biomedical Science Letters
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• v.19 no.1
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• pp.32-40
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• 2013

Pluripotent stem cells (PSCs) have enormous potential in the biomedical sciences because they can grow continuously and differentiate into any kind of cell in the body. However, for future application in regenerative medicine, it is still a challenge to control the differentiation of PSCs without using genetic materials. To control the differentiation of PSCs, small molecules might be the best substitute for genetic materials considering the following advantages: small size, which enables penetration of plasma membrane; easy-to-modify structure; and low chance of genetic recombination in treated cells. Herein, we introduce small molecules that induce the neuroectodermal differentiation of mouse embryonic stem cells (ESCs). The small molecules were identified via ESC-based consecutive screenings of small-molecule libraries composed of 324 natural compounds or 93 selected drugs. The natural compounds discovered in the first screening were used to select 93 structurally similar drugs out of 1,200 approved drugs. In the second screening, among the 93 compounds, we found 4 drugs that induced the neuroectodermal differentiation of ESCs. These drugs were progesteroneor corticoid-derivatives. Our results suggest that small molecules targeting the progesterone receptor or glucocorticoid receptor could be used as chemical tools to induce the differentiation of PSCs into a specific germ lineage.

• Smart Structures and Systems
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• v.13 no.6
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• pp.1065-1094
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• 2014

Civil engineers always face the challenge of uncertainty in planning, building, and maintaining infrastructure. These works rely heavily on a variety of surveying and monitoring techniques. Unmanned aerial vehicles (UAVs) are an effective approach to obtain information from an additional view, and potentially bring significant benefits to civil engineering. This paper gives an overview of the state of UAV developments and their possible applications in civil engineering. The paper begins with an introduction to UAV hardware, software, and control methodologies. It also reviews the latest developments in technologies related to UAVs, such as control theories, navigation methods, and image processing. Finally, the paper concludes with a summary of the potential applications of UAV to seismic risk assessment, transportation, disaster response, construction management, surveying and mapping, and flood monitoring and assessment.

• Proceeding of EDISON Challenge
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• 2017.03a
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• pp.499-505
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• 2017

Photoisomerizing molecules which can transform their structure by the light irradiation have great deal for the application of photo-switching devices. And azobenzene is the representive type of the photoisomerizing molecules. It can transform their trans- structures into cis- structure as the light for certain wave lengths they receive. This property shows the potential of ON/OFF switching functionalization which can be used into the nano scale photo switch. Furthermore, many studies are interested in the organic linkers that connect the azobenzene and metal electrodes. We used S, $CH_2S$, $(CH_2)_4S$ as the linker to watch the influence of linkers for electronic properties. So We suggest a photoswitching device based on the vertical junction using the first-principles calculations with density functional theory and non-equilibrium Greens function (NEGF). By analyzing the electronic structure and tunneling current caused by the structural difference of the system between cis- and trans- azobenzene, the difference in switching mechanism, ON/OFF ratio and transmission will be watched as the linker changes. And finally We will suggest which linker would be the better for the optimal device architecture which can achieve high control of the ON/OFF photocurrent ratio. This result will show the potential of azobenzene-based photoswitch and provide the critical insight in constructing the optimal device architecture.

• Journal of Information Science Theory and Practice
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• v.12 no.1
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• pp.77-86
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• 2024

As the significance of knowledge convergence continues to grow, universities are making efforts to develop methods that promote multidisciplinary learning. To address this educational challenge, our paper applies network theory and text mining techniques to analyze university curricula and introduces a graphical syllabus rendering method. Visualizing the course curriculum provides a macro and structured perspective for individuals seeking alternative educational pathways within the existing system. By visualizing the relationships among courses, students can explore different combinations of courses with comprehensive search support. To illustrate our approach, we conduct a detailed demonstration using the syllabus database of Yonsei University. Through the application of our methods, we create visual course networks that reveal the underlying structure of the university curriculum. Our results yield insights into the interconnectedness of courses across various academic majors at Yonsei University. We present both macro visualizations, covering 18 academic majors, and visualizations for a few selected majors. Our analysis using Yonsei University's database not only showcases the value of our methodology but also serves as a practical example of how our approach can facilitate multidisciplinary learning.