Study on two privacy-oriented protocols for information communication systems

In these days, the privacy of a user in information communication system is more important than ever before. Especially, the property is important for mobile communication systems due to the mobility of underlying mobile devices. Until now, many cryptographic tools have been proposed for achieving users’ privacy. In this paper, we review two privacy-oriented cryptographic protocols, and show their security holes. We also provide some countermeasure to fix the weaknesses. First, we discuss the security of the user identification scheme proposed by Hsu and Chuang which permits a user to anonymously log into a system and establish a secret key shared with the system. We show that the Hsu-Chuang scheme is not secure against known session key attacks, and then we provide a countermeasure which can be used for enhancing the security the Hsu-Chuang scheme. Secondly, we review a deniable authentication proposed by Harn and Ren which protects the privacy of a message sender. Then we show that the protocol has a potential incompleteness and two weaknesses.     

Anticancer activity of bovine α‐lactalbumin treated with microbial transglutaminase

This study investigated the effects of bovine α‐lactalbumin (α‐La) treated with microbial transglutaminase on human cancer cells, cell cultures and growth rate assays. The anticancer activity for 10 mg/mL of bovine α‐lactalbumin (α‐La) was measured as ～90% in a human colorectal cancer cell line HCT 116. For the human bone cancer cell line SJSA‐1, α‐La hydrolysis resulted in higher cytotoxicity compared to untreated tumour cells. The formation of polymers of α‐La was suppressed by the addition of ethylenediaminetetraacetic acid, indicating that polymers of α‐La are promoted by metal ions such as Ca²⁺. The effect of α‐La on the morphology of SJSA‐1 cells was manifested as morphological changes compatible with apoptosis. Bovine milk α‐La with and without microbial transglutaminase is considered a valuable food ingredient and a nutraceutical for human health.     

A study of the human hair structure with a Zernike phase contrast X-ray microscope

We have observed the internal structure of human hair shafts with a transmission Zernike phase contrast hard X‐ray microscope. Due to the high spatial resolution and the high contrast of the microscope, we could image scales, macrofibrils, medulla and melanin without staining. The structure of a black hair shaft is compared with that of a white one.     

Computer-based controller design for quantum boost series resonant rectifier

To obtain a stable output voltage from a recently-developed rectification circuit called a quantum boost series resonant rectifier (QBSRR), two control schemes, digital PI (proportional-integral) control and deadbeat control, are derived for a computer-based system. Since the output voltage regulation loop has a sampling time corresponding to the zero crossing point of the AC line voltage, the output voltage can be controlled regardless of the 120 Hz ripple component. By deriving a simple and exact model for the current program loop (open loop) of a QBSRR and using the pole-assignmenl technique, the controller gains can be systematically designed in the digital PI control scheme. The deadbeat control scheme is also developed to maintain fast dynamic performance in the presence of any load variations. In this control scheme, the controller gain is adjusted in accordance with the load information using a load estimation method. Simulation and experimental results are presented to verify the usefulness of these two control schemes.     

Signcryption with fast online signing and short signcryptext for secure and private mobile communication

Signcryption scheme is one of the useful tools for secure communication where authenticity and confidentiality are simultaneously required.Now,mobile devices are more and more widely used for communication,and thus it is desirable to design a scheme suitable to mobile applications.In this paper,we propose a signcryption scheme which is efficient enough to be implemented on mobile devices.In our scheme,we need only one multiplication in an online phase,and thus a signcryptor can generate a signcryptext very efficiently in the online phase.Moreover,the size of signcryptext is very short compared with exsiting schemes,and thus our scheme is very efficient in terms of communication overhead.The security of our signcryption scheme is proven in the random oracle model.     

Weakness in a RSA-based password authenticated key exchange protocol

Recently, an efficient password-authenticated key exchange protocol based on RSA has been proposed by Park et al. with formal security proof. In this letter, we analyze their protocol, and show that, unfortunately, it is insecure against an adversary who performs a dictionary attack.     

Design and Analysis of a Gain-scaling Controller Applied to a Chain of Integrator System with Measurement Noise on Feedback Sensor

A control problem of a chain of integrator system with measurement noise on feedback sensor is considered.We propose a gain-scaling controller for compenasating measurement noise of feedback sensor.Because control systems operate via feedback sensor' s signal,the measurement noise in sensor' signal results in performance degradation or even system failure.Therefore,control systems often demand on compensating measurement noise.Our controller is equipped with a compensator and gain-scaling factor in order to reduce the effect of measurement noise on feedback sensor.     

PopFlow: a novel flow management scheme for SDN switch of multiple flow tables based on flow popularity

Pipeline processing is applied to multiple flow tables (MFT) in the switch of software-defined network (SDN) to increase the throughput of the flows. However, the processing time of each flow increases as the size or number of flow tables gets larger. In this paper we propose a novel approach called PopFlow where a table keeping popular flow entries is located up front in the pipeline, and an express path is provided for the flow matching the table. A Markov model is employed for the selection of popular entries considering the match latency and match frequency, and Queuing theory is used to model the flow processing time of the existing MFTbased schemes and the proposed scheme. Computer simulation reveals that the proposed scheme substantially reduces the flow processing time compared to the existing schemes, and the difference gets more significant as the flow arrival rate increases.