A Framework for Secure NFC Applications

Jianchao Luo,Zhijie Qiu 보안공학연구지원센터 2015 International Journal of Multimedia and Ubiquitous Vol.10 No.3

Near Field Communication (NFC) technology provides a more natural and intuitive way for users to interact with intelligent environments within close proximity. It can be used in many scenarios including ticketing, advertising, controlled access, etc. However, NFC applications, especially those installed to the Secure Element (SE) for secure usage, have not yet been deployed widely enough in commercial environment. One reason is that the market is emerging and NFC-enabled smartphones are still very limited. Another reason is the life-cycle management of NFC applications on the SE is very complicated for application providers since the NFC business ecosystems have not yet taken off. In this paper, in order to establish a secure operating environment for third-party NFC applications, we propose a trusted NFC application management framework, which provides secure application provisioning and life-cycle management services. With the framework, NFC smartphone users can find and download interested NFC applications easily, and application providers can deploy NFC applications on users' SEs in a simple but secure way.

Experimental and Analytical Studies of U-Shaped Thin-Walled RC Beams Under Combined Actions of Torsion, Flexure and Shear

Jianchao Xu,Shenggang Chen,Quanquan Guo,Yinghua Ye,Bo Diao,Y. L. Mo 한국콘크리트학회 2018 International Journal of Concrete Structures and M Vol.12 No.3

U-shaped thin-walled concrete bridge beams usually suffer the combined actions of flexure, shear and torsion, but no research about the behavior of U-shaped thin-walled RC beams under combined actions has been reported in literature. Three large specimens of U-shaped thin-walled RC beams were tested under different torque–bending moment ratios (T–M ratios) of 1:5, 1:1 and 1:0 to investigate the mechanical responses such as crack patterns, reinforcement strains, failure modes and ductility. The testing results showed that ductile flexural failures occurred for all three of the U-shaped thin-walled beam specimens, although the combined shear effect of circulatory torque, warping torque and shear force increased as the T–M ratio increased from 1:5 via 1:1 to 1:0, reflected by diagonal cracks and stirrup strains. More specifically, basically symmetrical flexural failure was dominated by the bending moment when the T–M ratio was 1:5; flexural failure of the loaded half of the U-shaped thin-walled section was dominated by the combined action of the bending moment and warping moment, while there were only a few cracks on the other half of the U-shaped section when the T–M ratio was 1:1; and anti-symmetrical flexural failure was dominated by the warping moment when the T–M ratio was 1:0 (pure torsion). A simple method to calculate the ultimate load of such U-shaped thin-walled RC beams under different T–M ratios was suggested, and the calculating results were corresponding well with the experimental results.

Highly Selective Amination of o- and p-Alkyl Phenols over Pd/Al2O3-BaO

Jianchao Ma,Huabang Wang,Meng Sun,Fan Yang,Zhiwei Wu,Donghua Wang,Ligong Chen 대한화학회 2012 Bulletin of the Korean Chemical Society Vol.33 No.2

A series of Pd-based catalysts were prepared and examined for the amination of 2,6-dimethylphenol in a fixedbed reactor. The best results were obtained for Pd/Al2O3-BaO with a conversion of 99.89% and a selectivity of 91.16%. These catalysts were characterized using BET, XRD, XPS, TEM and NH3-TPD. Doped BaO not only improved the dispersion of the Pd particles but also decreased the acidity of the catalyst, which remarkably enhanced the selectivity and stability of the catalyst. The generality of Pd/Al2O3-BaO for this kind of reaction was demonstrated by catalytic aminations of o- and p-alkyl phenols.

Superhydrophobic Ag–Cu Composite Metal Film as Surface-Enhanced Raman Scattering Substrate

Jianchao Wang,Hongsheng Luo,Xuliang Song,Xihong Zu,Jie Zhang,Yuxin Gu,Guobin Yi 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2018 NANO Vol.13 No.7

In this paper, a superhydrophobic Ag–Cu composite metal film was fabricated as surface-enhanced Raman scattering substrate. Ag–Cu composite metal film was prepared from galvanic displacement on commercial copper foil. The prepared silver films were modified by PFDT to create a stable superhydrophobic SERS platform. Superhydrophobic substrates were characterized by a variety of characterization methods, including scanning electron microscopy (SEM), X-ray diffraction (XRD), UV-Vis, XPS and Raman spectra. The superhydrophobic substrate could enrich probing molecules with the volatilization of solvent. Mathematical model was presented and applied to investigate concentration factor of hydrophobic substrate. The measurements were in good agreement with the calculation results. The superhydrophobic Ag–Cu composite metal film can reduce the detection limits and provide a new way to prepare efficient SERS substrates for ultra-low concentration detection.

Convective Heat Transfer Coeicient Model Under Nanoluid Minimum Quantity Lubrication Coupled with Cryogenic Air Grinding Ti–6Al–4V

Jianchao Zhang,Wentao Wu,Changhe Li,Min Yang,Yanbin Zhang,Dongzhou Jia,Yali Hou,Runze Li,Huajun Cao,Hafiz Muhammad Ali 한국정밀공학회 2021 International Journal of Precision Engineering and Vol.8 No.4

Under the threat of serious environmental pollution and resource waste, sustainable development and green manufacturing have gradually become a new development trend. A new environmentally sustainable approach, namely, cryogenic air nanofluid minimum quantity lubrication (CNMQL), is proposed considering the unfavorable lubricating characteristic of cryogenic air (CA) and the deficient cooling performance of minimum quantity lubrication (MQL). However, the heat transfer mechanism of vortex tube cold air fraction by CNMQL remains unclear. The cold air fraction of vortex tubes influences the boiling heat transfer state and cooling heat transfer performance of nanofluids during the grinding process. Thus, a convective heat transfer coefficient model was established based on the theory of boiling heat transfer and conduction, and the numerical simulation of finite difference and temperature field in the grinding zone under different vortex tube cold air fractions was conducted. Simulation results demonstrated that the highest temperature initially declines and then rises with increasing cold air fraction. Afterward, this temperature reaches the lowest peak (192.7 °C) when the cold air fraction is 0.35. Experimental verification was conducted with Ti–6Al–4V to verify the convective heat transfer coefficient model. The results concluded that the low specific grinding energy (66.03 J/mm 3 ), high viscosity (267.8 cP), and large contact angle (54.01°) of nanofluids were obtained when the cold air fraction was 0.35. Meanwhile, the lowest temperature of the grinding zone was obtained (183.9 °C). Furthermore, the experimental results were consistent with the theoretical analysis, thereby verifying the reliability of the simulation model.

A Secure NFC-based Electronic Voucher Solution

Jianchao Luo,Zhijie Qiu 보안공학연구지원센터 2015 International Journal of u- and e- Service, Scienc Vol.8 No.4

As the number of mobile Internet users grows rapidly, more and more service providers are distributing electronic vouchers to consumers via mobile phones, which eliminates the need to carry various plastic or paper-based vouchers. Currently, electronic vouchers are available mainly in the form of text message or QR code. However, these types of vouchers are usually stored in the mobile phone that lacks secure storage and trusted execution environment. In addition, it is not efficient enough to input voucher code manually or get voucher QR code scanned when the consumer redeems the voucher. Near Field Communication (NFC) is a short-range wireless communication technology that simplifies the way of interaction between the electronic devices and guarantees a fast and secure information exchange. In this paper, we propose an NFC-based electronic voucher solution, which provides capabilities of distributing, managing and redeeming vouchers in a secure manner. The security of the voucher is ensured by storing it in the Secure Element (SE). With the proposed system, the consumer is enabled to redeem the voucher just by touching the NFC reader at the point of sale with his/her NFC phone, which offers better user experience than traditional electronic voucher solutions.

A Framework for NFC-based Context-aware Applications

Jianchao Luo,Hao Feng 보안공학연구지원센터 2015 International Journal of Smart Home Vol.9 No.1

Near Field Communication (NFC) is an emerging technology that facilitates data exchange between two devices wirelessly within close proximity. As integrated into more and more mobile phones, the NFC technology enables the users to interact with the intelligent environments in a natural and intuitive manner and thus changes the way people perform many routine daily activities like mobile payment, business card exchange, etc. Although NFC has bridged the physical and virtual worlds, context-aware technology is needed to sense and use NFC context actively in order to provide users with more intelligent and personalized services. In this paper, we propose an ontology-based framework for developing NFC-based context-aware applications, which can perceive user context and offer appropriate context-aware services to the user by combining the NFC technology with context-aware technology. With the proposed framework, application providers are enabled to develop NFC-based context-aware applications in a simple way. Meanwhile, the framework provides security service for protecting data integrity of the NFC context. This paper presents the framework's design, implementation and a real use case scenario that shows the validation of the approach.

Clean and facile synthesis of triuret from urea and dimethyl carbonate (DMC) under mild conditions

Jianchao Chen,Peihua Zhao,Hua Liu,Futian Zhu,Yaqing Liu 한국화학공학회 2012 Korean Journal of Chemical Engineering Vol.29 No.3

Triuret has been successfully synthesized by the reaction of urea with dimethyl carbonate (DMC) under mild conditions in the presence of potassium methoxide as a catalyst. It has been fully characterized by FT-IR, 1H-NMR,13C-NMR, and MS. Effects of the catalyst, the molar ratio of starting materials, and the reaction time on the obtained product were examined in detail. It was found that when n (urea) : n (DMC)=1.2 : 1, 6 h, and 0.8% catalyst, the yield of triuret can reach 98.1%. Especially, this novel procedure is reported for the first time and has many significant advantages such as easy and clean synthesis, simple work up, and high yields.

A Web-Based Framework for Lightweight Context-Aware Mobile Applications

Jianchao Luo,Hao Feng 보안공학연구지원센터 2016 International Journal of Database Theory and Appli Vol.9 No.4

As more and more intelligent sensors and sensing applications are equipped with, smartphones are becoming smarter and play a greater role in people's lives. However, due to mobile platform diversity, the development and deployment of a context-aware application for different mobile devices are time-consuming and expensive, which in fact limits the large-scale application of context-aware technology in mobile heterogeneous environments. Unlike native applications, web applications are easy to develop, upgrade and deploy, and almost all smartphones today include a web browser for supporting running them. Another difference is that native applications can capture context information by accessing sensors available on the mobile device, but web applications running in the browser cannot. In this paper, we describe CaMWAF, a framework designed to support the rapid development of context-aware mobile web applications and simplify the exchange of context information in heterogeneous environments. With CaMWAF, developing a context-aware application is no longer a difficult and time-consuming task. In consideration of the resource limitation of mobile devices, the proposed framework delegates the computationally expensive tasks to the server, while enables the context-aware mobile applications to query and subscribe high-level context information in an easy and lightweight manner.

A Common Data Storage Solution for SE-based Membership Card Applications

Jianchao Luo,Zhijie Qiu 보안공학연구지원센터 2015 International Journal of Smart Home Vol.9 No.3

In order to encourage customers to return, more and more retailers issue membership cards that offer certain exclusive benefits to the customers who own them. As it is not convenient for the customers to bring many plastic membership cards with them, electronic membership cards emerge. However, traditional electronic membership cards are stored in the mobile phone that usually lacks enough security protection. This paper presents a common data storage solution for SE-based membership card applications, which can enable retailers not only to deploy membership cards on secure area easily, but also to access membership cards in a fast and secure manner. Since the proposed solution provides common and simplified interfaces for managing membership card application information, the service providers will not have to know much about the complicated application management mechanism within a SE and thus the overhead of developing and deploying a SE-based membership card application is greatly reduced.