Kanazawa Technical College

Printing display images normally proceeds well provided they comply with the SDR gamut supported by color management systems (CMS), like ICM used in Windows OS. Twilight vision, unfortunately, complicates this process, as it is quite difficult to convert images captured by UHDR systems given that their contrast ratios (CR) sometime exceeded 10^6:1 or so; SDR images have CR values of approx. 100:1. A typical example is the reproduction of lunar texture. Quite recently, we resolved this problem by employing just global tone mapping (GTM). Even with the use of GTM, emissive displays like LCD, not projection displays or printed matter, are strongly recommended to prevent image quality degradation. This study addresses the reasons why CMS fail to handle twilight vision material well and proposes enhanced GTM for printing emissive display images. The main point is the difference between the perception responses demonstrated in daytime and in twilight, even after the UHDR material is converted into SDR images. In other words, the key idea is to focus on the underutilized top and bottom margins of the reproduced SDR images. From another viewpoint, the most important result is the acquisition of super sensitivity. Our proposal enables high sensitivity even with the same sensor (increase is approx. 10 to 30 times).

The community bus is indispensable for the local residents. Due to weather and traffic congestion, community buses may not operate on time. The local residents will have to wait for the bus in fear that they will not know when it will come. Therefore, we created a bus stop that displays the current position of the bus using a tablet terminal in order to eliminate the burden [1, 2, 3]. However, tablet terminal type bus stops were difficult for elderly people who were not familiar with smartphones and the Internet environment. In addition, in the case of bus stops without a power supply, the tablet terminal type bus stop was not suitable for long-term operation in terms of power consumption and cost. In this paper, we have created a bus stop that makes it easy for the elderly to understand by using LEDs to indicate the location of the bus. We also investigated the power consumption, operating cost, and usability of the LED type bus stops. As a result, we confirmed that it was improved from viewpoints that power, cost and user convenience.

We are developing a rice cultivation management systems using a field server to reduce the workload of farmers. At present, it is possible to manage environmental data for crops and fields using sensors. However, there are some points to be improved in the current field server. The first is that it does not support multi-hop, which limits the communication distance. The second is that it takes a long time to collect all data in a large-scale network. This paper introduces a multi-hop function of a field server using LoRa and a data aggregation algorithm that collects data in an acceptable time to solve the above problems. Also, in this verification, the aim is to further reduce the cost of the field server by not using expensive elements such as special crystals for managing the sleep time.

Measurement of road surface friction coefficient is significant to improve advanced driver-assistance systems (ADAS)．Almost of ADAS use the information obtained from wheel speed sensors, acceleration sensors, etc. However, it is difficult to measure the road surface friction coefficients accurately with these sensors. Therefore, in order to develop an intelligent tire capable of measuring the road surface friction coefficients, various studies focus on tires that are the only parts of a car being grounded on road surface. However, such an intelligent tire has not been put to practical use due to the difficulty of stable measurement of deformation induced on a tire and difficulty in estimating the road surface friction coefficients from the deformation of the tire. Therefore, this study focuses on the deformation of a wheel and proposes a method to measure road surface friction coefficients from strains induced on the surface of not a tire but a wheel. The study clarifies the relationship between the strains on a wheel and the loads acting on the tire from the grounding surface by using an experimental apparatus capable of simulating complete slip running. In addition, a simple method of measuring road surface friction coefficients is proposed by means of the obtained relationship.

PurposeThis paper aims to present a Halbach magnet array linear machine, without an iron core and the electromotive force (EMF) characteristic results.Design/methodology/approachThe linear machine was made with mover coils and a permanent magnet stator without an iron core. For an outline design, the analyzed magnetic density results were compared to the Halbach array with a horizontal array using the 3D finite element analysis. The test was carried out on an experimental system using a prototype linear machine. The EMF of the linear machine, with applied Halbach array magnetic circuit, is verified with the experiment.FindingsThe EMF peak value of the Halbach array is larger than the EMF of the horizontal array. Compared to the EMF in the experimental results, the effective value of the Halbach array is 1.69 times greater at an average operation speed of 373 mm/s.Originality/valueThe core-less linear machine has advantages of reduced cogging torque and iron loss because both the stator and the mover do not have an iron core. The stator and rotor will not rust from water. In this paper, it is clear from the basic electrical characteristics that the linear machine, with applied Halbach array, is larger than the EMF of the horizontal array.

Previously, in order to measure friction coefficients of tire grounding surface in car slipping, a cantilever-type sensor that can detect the vertical load and friction force as well as the direction of the friction force simultaneously has been proposed. The sensing part, which contacts grounding surface, of the proposed sensor is pulled out of the tire tread through a hole. However, penetrating the hole through tire tread part has some problems: leakage of air from the tire, weakening of the rigidity etc. Therefore this study proposes a sensor that can be installed on the inner surface of a tire without penetrating hole through the tire tread by filling the detecting part of the sensor in the inner part of the tire tread. If the detecting part filled in the inner surface has sufficient airtight structure from the integral manufacturing, the durability of the sensor as well as retaining air pressure are expected. This study measured the deformation of the inner part of the tread through the detecting part under high-load at tire slipping state. Furthermore, relation between the measurement values and the force applied to the tire from grounding surface was clarified. As a result, the study confirmed that the proposed method can detect the friction coefficients between the tire and tire grounding surface.

The stereo matching image processing is studied by the characteristic area properties, the geometrical restrictions and color comparisons. The characteristic areas are the 4 directional connectivity areas bound by the edge parts. The geometrical restrictions are the size difference ratio between the characteristic areas, matching point displacement ratio between the centers of the gravity of the characteristic areas, the size distortion ratio between the added stereo matching pattern union and the reference stereo matching pattern. The proper stereo matching conditions are the state of the maximum and sufficient large pixel number on the overlap area, the satisfaction of the condition of the average row difference ratio on the overlap area, the similar state of the average color difference on the overlap area on the proper combinations of the characteristic areas. The ability of the studied stereo matching is experimented with respect to the colorful soccer ball object. The result of the stereo matching experiments provide the proper correspondence between the centers of the gravity of the characteristic areas. The geometrical restrictions is effective to select the good combination between the characteristic areas of the stereo matching patterns.