n-Sik Yu

Studies on enhanced colloidal stability and heating ability of glycine functionalized LSMO nanoparticles for cancer hyperthermia therapy

Magnetic nanoparticles offer potential advances in cancer treatment. In the present research, La0.7Sr0.3MnO3 (LSMO) nanoparticles were synthesized via a facile combustion method. A novel bilayer coating of glycine was used for stabilization. The as-prepared, monolayer and bilayer coated nanoparticles were characterized by X-ray diffractometry, Fourier transform infrared spectroscopy, transmission electron microscopy, dynamic light scattering, zeta potential measurement and vibrating sample magnetometry studies. The aqueous suspensions of bilayer coated LSMO showed good colloidal stability even after a long period of time. Magnetic measurements showed negligible coercivity and remanence values at room temperature implying superparamagnetic behaviour of the LSMO magnetic nanoparticles. The specific absorption rates of these magnetic nanoparticles are found to be 26–75 W g−1 in different physiological media such as phosphate buffered saline (PBS), glucose, NaCl and bovine serum albumin (BSA) protein, and their values are suitable for hyperthermia treatment of cancer cells under an alternating current (AC) magnetic field. The cytotoxicity of magnetic nanoparticles coated with monolayer and bilayer glycine was studied in a MCF-7 cell culture. The potential for using bilayer functionalized LSMO nanoparticles in cancer cells was studied, and the cell viability of these nanoparticles against MCF-7 breast cancer cells is significantly enhanced as compared to monolayer and non-functionalized LSMO nanoparticles. Such nanoparticles with enhanced cell viability and enhanced specific absorption rates hold great promise for use in the intracellular hyperthermia treatment of cancer tumors.

Oxygen pressure dependent structural and optoelectronic properties of pulsed laser deposited Ga-doped ZnO thin films

Transparent and conducting 2 at.% Ga-doped ZnO (GZO) thin films were grown on glass substrates at 400 °C using pulsed laser deposition (PLD) technique at various oxygen pressures. The influence of oxygen ambient pressure on structural, electrical and optical properties of GZO thin films was systematically investigated. XRD analyses show that all the films are crystallized in the wurtzite phase and exhibit a preferential orientation along the c-axis. Hall effect measurements confirmed that all the films are heavily doped degenerate semiconductors with n-type electrical conductivity. The film resistivity increases with increasing oxygen pressure due to the reduction in oxygen vacancies and absorption of oxygen species. All the films are highly transparent in the visible region (T ≥ ~84% at 550 nm) and the optical band gap is found to be red shifted from 3.61 eV to 3.42 eV with an increase in oxygen pressure. The GZO film grown at an optimized oxygen pressure of 7 × 10−3 torr exhibits highest figure of merit (~90 Ω−1) because of its optimum sheet resistance (3.39 Ω −1) and optical transmittance (~89%).

Study on FBG Sensors for Hull Stress Monitoring

Vessels receive stress during their navigations as well as during their cargo operations. This stress may cause damages to the hull and may result in accidents. So the hull stress monitoring system(HSMS) is recommended in order to prevent these accidents. In this paper, we manufactured fiber Bragg grating(FBG) sensor and the model ship for towing tank experiments. The strain characteristics of the model ship on the water wave were measured through the towing tank experiment. The FBG sensors and electric strain gauges were attached on the connection jig, and then the characteristics of the FBG sensor were compared with those of the electric strain gauge. The strain of model ship was increased according to the increment of the amplitude of water wave. In particular, the largest strain was measured in the center of the model ship. As the wave period increased, the strain of model ship was decreased.

Study on asynchronous data transmission of MediaLB bus communication

As demands increase for the Infotainment System, the Multimedia Networking technology for automobile, called MOST (Media Oriented Systems Transport), has been actively applied to the automobile industry, to meet the demands of the Infotainment System. MOST is define the protocol, H/W and S/W layers to support the transportation of synchronous, asynchronous and control data in an efficient and low cost way. The existing MOST devices relied on 12C, 12S communication mode for internal bus communication but the widening bandwidth in the MOST network and additional installations in a single device required bus communication and MediaLB(Media Local bus). Majority of the existing MOST devices use I2S or I2C bus communication mode to process synchronous data (stream data) and asynchronous data (packet data). Hence, this study will take a look at control channel and transmission mechanism of synchronous data and asynchronous data by applying MediaLB mode, which is an advance from 12S or 12C bus communication mode proposed by MOST network and currently in use, suggest an efficient way to transmit asynchronous data and analyze its performance.

A study on the twin domain of Pb3(PO4)2 ferroelastic crystal

Abstract Ferroelastic Pb3(PO)4)2 crystal exhibits two types of domain walls. We constructed the geometrical lattice structure in the vicinity of the domain walls and observed the tilted angle of the W′-walls geometrically. Using the polarization microscope we investigated the temperature dependence of the domain wall and the change of the conoscope image at the phase transition temperature. Near Tc . the narrow domains between two W′-walls were widened and new needle shape W-walls appeared. Above Tc we observed the separation of the Isogyre in the conoscope image by the rotation of the crystal plate, which was inferred due to the infinitesimal lattice mismatch between the cleavage planes above Tc .

The crystal growth of BiNbO4

Abstract The single crystal of BiNbO4 was grown by Czochralski technique and determined its crystallographic axes at room temperature. The optimum conditions for pulling and rotation speeds were 1.2mm/hr and 15 rpm respectively at 1,130 °C. BiNbO4 was found to undergo two phase transitions at 562 °C and 470 °C from temperature dependence measurements of dielectric constants and Raman spectra were studied for X(ZZ)Y, X(YX)Y, X(YZ)Y geometries.

Implementation of Automotive Multimedia Interface Supporting Multi-Channel Display in Multi-Screen Display

Recently, the diverse needs of the drivers for in-vehicle infotainment systems are increasing rapidly. As a result, the infotainment systems are equipped with more convenient and human-friendly high-tech features. In this paper, we designed and implemented in-vehicle multimedia infotainment system based on embedded system that was applied various multimedia to in-vehicles. The proposed system can support independent display on each screen for the multi-channel multimedia source based on one processor(1 CPU). Therefore, our system can be reduced costs compared to other systems. This system not only displays the video and audio data in storage devices but also displays CAM, T-DMB, and DVB-T multimedia contents which are supplied in real-time services. Also, our system could multi-screen displays multimedia data in smart phone using Wi-Fi. We expect that in-vehicle infotainment systems like AVN(Audio video navigation) and RSE(Rear Seat Entertainment) could be used in various applications and reduced costs.

Spectroscopic Characterization of 400℃ Annealed Zn x Cd 1-x S Thin Films

II~VI compound semiconductors, thin films have been synthesized onto indium-tin-oxide(ITO) coated glass substrates using thermal evaporation technique. The composition ratio x() was varied to fabricate different kinds of thin films including CdS(x

A Study on the Development of Real-Time Analysis Monitoring System and Its Application of Medical Ins

By the period of Big Data, the share of open public data and result for bio has actively moved around advanced country, and policy of promote big data development and utilization have been pushed forward for improvement of market competitive power. The most receive attention industry is health and medical treatment.

Development of Total IT Service Monitoring System

With the recent emergence and popularity of e-business, and the increasing complications of our modern day IT infrastructure, companies have been minimizing their IT infrastructure and making much more investments into cost and personnel in order to ensure ongoing and stable services. This is being done to cope with our modern day rapidly changing business environment. However, in spite of much effort being done, they have not been as effective as what they were expecting, with frequent service downtime due to fault and response time, which raised the essential tasks to find the causes through IT infrastructure monitoring and extended application, rather than to find the causes only from the aspects of hardware in the past. In this study, about how the IT monitoring system was developed, to see many service actions that configure IT services (eg. Server/database/network), by implementing the Agentless real-time monitoring system under the cloud computing environment.