Narrow band photometry of selected asteroids

The CCD photometry of selected asteroids was carried out to check for possible cometary activity in them. To distinguish the asteroids with possible cometary activity from those of the main belt, each object of interest was observed in two filters; one centered on the C2 emission band at 5140A (90A bandpass) and the other centered on the nearby continuum at 4845A (65A bandpass). None of the observed asteroids appear to have any C2 emission

Changing Paradigm of Indo-Japan Relations - Opportunities and Challenges

Indias growing economic strength in recent years has seen it adapting its foreign policy to increase its global influence and status and to meet the challenges of the 21st century. In the past few years, New Delhi has expanded its strategic vision, most noticeably in Asia, and has broadened the definition of its security interests. As a result, India-Japan relations have undergone a paradigmatic shift which has seen an attempt to build a strategic and global partnership between the two countries. India and Japan share a special relationship as fellow democracies without hegemonic interests and with a similar propensity to seek peaceful resolution of conflicts and greater economic engagement in the Asian continent. This paper puts forward the argument that while there are certainly problems of communication and distance between the two countries, the changing international order including most notably, the rise of China will see the two countries increasingly thrown together on a variety of issues, some of which have been identified in the present work. Current and future economic and population dynamics in both the countries mean that India-Japan relations will continue to improve not just politically but also in economic terms.India, Japan, trade, FDI, ODA

Real-Time, Non-Intrusive Detection of Liquid Nitrogen in Liquid Oxygen at High Pressure and High Flow

An integrated fiber-optic Raman sensor has been designed for real-time, nonintrusive detection of liquid nitrogen in liquid oxygen (LOX) at high pressures and high flow rates in order to monitor the quality of LOX used during rocket engine ground testing. The integrated sensor employs a high-power (3-W) Melles Griot diode-pumped, solid-state (DPSS), frequency-doubled Nd:YAG 532- nm laser; a modified Raman probe that has built-in Raman signal filter optics; two high-resolution spectrometers; and photomultiplier tubes (PMTs) with selected bandpass filters to collect both N2 and O2 Raman signals. The PMT detection units are interfaced with National Instruments Lab- VIEW for fast data acquisition. Studies of sensor performance with different detection systems (i.e., spectrometer and PMT) were carried out. The concentration ratio of N2 and O2 can be inferred by comparing the intensities of the N2 and O2 Raman signals. The final system was fabricated to measure N2 and O2 gas mixtures as well as mixtures of liquid N2 and LO

Current status of drug screening and disease modelling in human pluripotent stem cells

The emphasis in human pluripotent stem cell (hPSC) technologies has shifted from cell therapy to in vitro disease modelling and drug screening. This review examines why this shift has occurred, and how current technological limitations might be overcome to fully realise the potential of hPSCs. Details are provided for all disease-specific human induced pluripotent stem cell lines spanning a dozen dysfunctional organ systems. Phenotype and pharmacology have been examined in only 17 of 63 lines, primarily those that model neurological and cardiac conditions. Drug screening is most advanced in hPSC-cardiomyocytes. Responses for almost 60 agents include examples of how careful tests in hPSC-cardiomyocytes have improved on existing in vitro assays, and how these cells have been integrated into high throughput imaging and electrophysiology industrial platforms. Such successes will provide an incentive to overcome bottlenecks in hPSC technology such as improving cell maturity and industrial scalability whilst reducing cost

Orbit and spin evolution of the synchronous binary stars on the main sequence phase

The sets of the synchronous equations are derived from the sets of non-synchronous equations The analytical solutions are given by solving the set of differential equations. The results of the evolutionary tendency of the orbit-spin are that the semi-major axis shrinks gradually with time: the orbital eccentricity dereacses gradually with time until the orbital circularization; the orbital period shortens gradually with time and the rotational angular velocity of primary component speed up with time gradually before the orbit-rotation achieved the circularization The theoretical results are applied to evolution of the orbit and spin of synchronous binary stars Algol A, B on the main sequence phase The circularization time and life time (age) and the evolutional numerical solutions of orbit and spin when circularization time are estimeted for Algol A, B. The results are discussed and concluded.Comment: 8 pages, accepted for publication in RA

A Streamline Upwind/ Petrov-Galerkin FEM based time-accurate solution of 3D time-domain Maxwell\u27s equations for dispersive materials

Although the simulation of most broadband frequency responses are made under the assumption of constant electromagnetic material parameters, this is not a valid assumption for many materials found in nature. In this dissertation the time-accurate solution of the 3D time-domain Maxwell’s equations for dispersive materials in a Streamline Upwind/Petrov-Galerkin framework is investigated. For this purpose the permittivity associated with a material is expressed as a matrix, enabling the solution of anisotropic material models with multiple poles. Here diagonally isotropic models with up to 2 poles are investigated. Near-field to far-field transformations are implemented to enable the solution of open boundary problems such as radiation patterns and radar cross sections. A unified perfectly matched layer absorbing boundary layer is implemented to efficiently terminate the computational region. Numerical simulations of these equations are tightly coupled together and compared against a loosely coupled approach to improve efficiency. An alternative diagonal stabilization matrix is proposed which is implemented and compared with a non-sparse stabilization matrix derived from the flux Jacobians. Along with this new stabilization parameter, scalability is improved by coupling the equations for the perfectly matched layer with those of Maxwell’s equations. Further efficiency gains are achieved by allowing for a variable number of equations to be solved throughout the domain

Factors Influencing The Human Preferred Interaction Distance

Nonverbal interactions are a key component of human communication. Since robots have become significant by trying to get close to human beings, it is important that they follow social rules governing the use of space. Prior research has conceptualized personal space as physical zones which are based on static distances. This work examined how preferred interaction distance can change given different interaction scenarios. We conducted a user study using three different robot heights. We also examined the difference in preferred interaction distance when a robot approaches a human and, conversely, when a human approaches a robot. Factors included in quantitative analysis are the participants' gender, robot's height, and method of approach. Subjective measures included human comfort and perceived safety. The results obtained through this study shows that robot height, participant gender and method of approach were significant factors influencing measured proxemic zones and accordingly participant comfort. Subjective data showed that experiment respondents regarded robots in a more favorable light following their participation in this study. Furthermore, the NAO was perceived most positively by respondents according to various metrics and the PR2 Tall, most negatively. A follow up study involved finding out if there is any correlation between the robot's height and the method of approach focus across each proxemic zone based on the results obtained from our prior work. In addition, we conducted an user study to understand how interaction distance between a human and a robot changes with the change in the robot's physical configuration such as arm position (extended versus tucked in) and gaze (robot directly looking at the participant versus robot being distracted reading a newspaper). Data collected from this experiment was used to study the relationship between the physical configuration of the robot and preferred interaction distance. Subjective measures included human comfort and perceived safety. The results obtained through this study shows that robot's arm position and gaze behavior did have a significant effect in influencing measured proxemic zones. Subjective data showed that the experiment did have a short-term impact on the participants' opinion on the robot

Fiber Optic Raman Sensor to Monitor Concentration Ratio of Nitrogen and Oxygen in a Cryogenic Mixture

A spontaneous Raman scattering optical fiber sensor is developed for a specific need of NASA/SSC for long-term detection and monitoring of the quality of liquid oxygen (LOX) in the delivery line during ground testing of rocket engines. The sensor performance was tested in the laboratory and with different excitation light sources. To evaluate the sensor performance with different excitation light sources for the LOX quality application, we have used the various mixtures of liquid oxygen and liquid nitrogen as samples. The study of the sensor performance shows that this sensor offers a great deal of flexibility and provides a cost effective solution for the application. However, an improved system response time is needed for the real-time, quantitative monitoring of the quality of cryogenic fluids in harsh environment