The luminance resolution characteristics of multi‐primary‐color display

Abstract— In this paper, the resolution characteristics of multi‐primary‐color (MPC) display systems are analyzed. That four‐primary‐color (4PC) displays can increase the effective resolution for achromatic images in the luminance domain by a factor of two as compared to conventional RGB‐based displays with MPC‐specialized subpixel rendering, which is proposed in this paper, is demonstrated. Five‐ and six‐primary‐color (5PC and 6PC) display systems can reproduce denser luminance data than conventional RGB‐based display systems and solve a problem of MPC displays, viz. an increase of production costs and a decrease in the aperture ratio caused by increasing the number of subpixels in one pixel. This is an essential advantage of MPC display systems, which is related to the combination of the proposed color‐filter architecture and image processing. Thus, a completely new advantage of MPC display systems, in addition to their well‐known capabilities of color reproduction and power saving, is proposed.     

Potential of a Combination of UASB and DHS Reactor as a Novel Sewage Treatment System for Developing Countries: Long-Term Evaluation

A novel municipal wastewater treatment system, consisting of a combination of an upflow anaerobic sludge blanket (UASB) and down-flow hanging sponge (DHS) posttreatment unit, was continuously evaluated for more than three years with raw sewage as an influent. The system was installed at a sewage treatment site and operated at 25±3°C. This paper reports on the results of a long term monitoring of the system. The whole experimental period was divided into three distinct phases with different operating conditions. Organic pollutants were only partially removed in anaerobic UASB pretreatment unit. The remaining organics as well as nitrogenous compounds were almost completely removed by the DHS posttreatment unit. In all phases the system demonstrated removal efficiency consistently over 95% for unfiltered biochemical oxygen demand (BOD), 80% for unfiltered-chemical oxygen demand and 70% for suspended solids. The system produced an excellent effluent quality with only 4–9?mg/L of residual unfiltered BOD. Dissolved oxygen in the final effluent was 5–7?mg/L although no aeration was provided to DHS system. Moreover, excess sludge production from DHS was negligible thus eliminating secondary sludge that is troublesome to dispose off. The system also exhibited substantial stability against twofold hydraulic shock load and fourfold organic shock load. The results suggested that the proposed system may be a competitive solution for municipal sewage treatment under variable conditions.     

Superconductivity and Ferromagnetism of the Ru-1232 Compounds in the (Ru1?xNbx)Sr2(GdCe1.8Sr0.2)Cu2Oz System

The Ru-1232 compounds have been synthesized in the (Ru_1–xNb _x )Sr₂(GdCe_1.8Sr_0.2)Cu₂O _z system, and effects of Nb substitution for Ru on superconductivity and ferromagnetism of the Ru-1232 compounds have been investigated. First, X-ray powder diffraction study shows that nearly the single 1232 phase samples can be obtained in the x composition range from 0.0 to 0.3. Then, from the electrical resistivity study, it is found that each of the samples shows resistivity dropping phenomenon at two temperatures of T _c ^l and T _c ^h, which originates from superconductivity of the Ru-1232 phase and the Ru-1222 one, respectively. Both of the starting temperatures are lowering with increasing Nb content x. Lastly, from the magnetic susceptibility study, it is found that superconducting transition temperature T _c is 20 K for the Ru-1232 sample with x = 0.0 and the ferromagnetic transition temperature T _m is about 90 K. This study also shows that both of the values of T _c and T _m become low with increasing x from 0.0 to 0.3.     

Possibility of Superconductivity of the 2212 Phase in the Bi(Pb)-Sr-Ce-Cu-O System

Synthesis of the Bi-2212 compound in the Bi-Sr-Ce-Cu-O system has been already known. But, there has been no report on superconductivity of the compound yet. We have prepared many Bi-2212 samples partially substituted by Pb for Bi in the Bi-Sr-Ce-Cu-O system. The nominal composition is (Bi_{2− y} Pb _y )Sr₂(Sr_{1− x} Ce _x )Cu₂O _z . Then, we have investigated possibility of superconductivity for the samples. As a result, we find that a sample with nominal composition of x=0.23 and y=0.1, which is of almost the single 2212 phase, shows an anomaly at about 70 K in addition to temperature dependence of the resistivity like a semiconductor. Furthermore, the sample also shows a decrease of magnetic susceptibility starting at about 70 K with decreasing temperature. These experimental results can be considered to result from superconductivity of the 2212 phase in the Bi(Pb)-Sr-Ce-Cu-O system.     

Finite element method analysis and control of micro actuator with piezoelectric element for spinstand

A micro actuator was introduced to achieve highly precise track following with an head gimbals assembly (HGA) for a spinstand tester. The actuator constructed with a piezoelectric element and a stroke amplifying mechanism was designed by using finite element method analysis. According to robust controller using H_∞ control theory was designed so as to guarantee the control performance for two kinds of HGAs. As the experimental results of the step response show, it was found that the settling time and the rise time were about 3.0 ms and about 1.0 ms, respectively.     

Linear actuator for precise track following

A new air bearing linear actuator with a Voice Coil Motor (VCM) was investigated for a precise head track following in an Hard Disk Drive (HDD) magnetic recording tester system. The actuator has a servo bandwidth of two times as wide as that of a conventional HDD, due to a high stiffness without any friction. A low-pass filter was introduced to precisely monitor the step response behavior by reducing the relatively large noise of the used optical fiber sensor. The effect of the low-pass filter was investigated comparing with the other method. Track following accuracy was also tested by using a conventional 2.5-inch hard disk drive. The head installed on the actuator could follow on a track by using Position Error Signal (PES) from the servo pattern. When a Double Metal In Gap (D-MIG) head of 4 μm track-width was loaded on a disk rotating at 4200rpm, the tracking error could be compressed down to one-twentieth of the track-width. The tested system did not show any azimuth error of head-tracking due to the linear motion. In conclusion, the air-bearing linear actuator is suitable for a precise track following mechanism of a spin-stand tester for an HDD system.     

Stereological correction method based on sectional texture analysis for the liberation distribution of binary particle systems

Accurate assessment of liberation state of ore sample is important in mineral processing. In practice, the ore sample is mounted in resin, sectioned, and polished before its liberation state is measured by sectional analysis. This approach typically overestimates the degree of liberation in two-dimensional (2D) measurements. Several models have been proposed to overcome this stereological bias and correct this error in well-examined samples. However, their versatility remains poorly understood. Herein, a stereological correction method was developed for the liberation distribution. First, the complexity of particle sectional texture was assessed using the fractal dimension of the image intensity. Next, the magnitude of stereological bias and 2D measureable parameters such as fractal dimension was correlated by an all-encompassing simulation of various texture types. Finally, stereological correction indices were exclusively estimated from 2D measureable parameters obtained through the correlation. This model exhibited high versatility based on the all-encompassing simulation. The model was validated using nine different irregularly shaped binary particle systems and assessed using areal difference and maximum difference between liberation distribution curves in two and three dimensions. This error indices improved by approximately 80% for the former error index and 90% for the latter index.     

Microscopic observation of voids and transverse crack initiation in CFRP laminates

In situ three-point bending tests under observation using scanning electron microscopy were performed for specimens including voids to investigate the effect of voids on transverse crack initiation in carbon fiber-reinforced plastic (CFRP) laminates. First, initial failure load (i.e. applied load at the first transverse crack initiation) was investigated. Microscopic strain distributions were then measured by digital image correlation analysis using SEM pictures taken before and during loading in the in situ tests. In addition, specimens including voids and transverse cracks after the in situ tests were observed using X-ray computed tomography to clarify transverse crack onset locations with respect to void shapes and distributions. These experiment results suggested that voids actually caused strain concentration and corresponding local plastic deformation, and finally resulted in reduction of macroscopic initial failure strains in CFRP laminates.     

From needs to aspirations in information technology for development

ABSTRACT

“Needs” figure prominently both in the technology sector and in international development. Both fields refer frequently to people’s needs and perform needs assessments. But, the two groups differ on what needs are. The technologist’s conception is represented in such statements as, “the user needs to see shoes in various colors on an e-commerce website.” Development focuses on more basic needs such as nutrition, health, and employment. We argue that conflating these two classes of needs is a subtle but underlying cause of myopic technological interventions. While development is increasingly understood to require changes in human capital, institutional capacity, and mass values – traits internal to people and societies – the technologist’s conception of needs suggests solutions that change external context through technological artifacts. We propose an approach to ICT and development that is focused less on needs, and more on aspirations. We rationalize aspirations as a basis for action, and present preliminary evidence in the form of a survey and three brief case studies for the viability of aspiration-based approaches to development.