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In this study we reviewed the use of genetic information in the Ecologically or Biologically Significant Marine Areas (EBSA) of Convention on Biological Diversity (CBD). We also evaluated genetic indicators for each criterion of important marine areas. We proposed five genetic indices, mainly based on microsatellite analysis (e.g., private allele frequency and number of cryptic species), then selected EBSAs in tropical and temperate zones of Japan based on eight coral species as a case study. Finally, we compared the results with the findings from conventional species-based EBSAs. In the EBSAs genetic information was mainly used in the Northern Hemisphere, particularly in the Baltic Sea; it was rarely applied in the Southern Hemisphere and Asian regions. Although typically applied to large organisms, genetic information is used to various organisms, including benthic and bacterial communities. Genetic data are used as indicators of diversity and endemism. Genetic indices were available for all seven EBSA criteria, but only five indices of three criteria were used. Examination of important areas of corals in the temperate zone using these indices showed that the indices without genetic indicators extracted a large number of important areas in the tropics; however, the use of genetic indicators identified important locations, including in temperate zones. Comparison with conventional, mainly species-based non-genetic methods showed less than 50% agreement, although particularly important sites in marine protected areas were identified by both methods. While there is still more work to be done, such as consideration of the number of survey sites or target species, one reason is that species-based methods tend to evaluate tropical areas higher. Therefore, these genetic indices are useful for examining important regions, particularly in temperate zones; they revealed cryptic lineages, indicating that many unknown marine taxa should be considered in vulnerable marine areas. Some indicators could be extracted with additional effort, such as population size estimation, immigration, or the use of next-generation sequencing, thus guiding future studies. Because limited genetic information was available in the early stages of EBSA selection, there is a need for systematic surveys and evaluations, particularly in the Southern hemisphere, Asian region, and in small organisms.

The thermoelectric hydrogen (H2) gas sensor using PCB (Printed Circuit Board) technique was developed based on the exothermic absorption of H2 by a palladium (Pd) film coated on a thermocouple. A cascade connection of two thermocouples composed of copper (Cu) and constantan (55% nickel and 45% Cu) was used to detect the exothermic absorption of H2 by Pd. The differential thermoelectric voltage output between the two thermocouples (with and without the Pd film) increased linearly with the H2 gas concentration in a 2.0–50 vol% ambient atmosphere. Standard deviations (SD) for 8 measurement cycles are typically 1.1% at 4 vol% H2, 0.81% at 6 vol% H2, and 1.9% at 8 vol% H2, respectively. The differential thermoelectric voltage output can be detected from 2.0 vol% H2 atmosphere. The ambient temperature fluctuations on the measurement was also effectively reduced using the cascade connection of two thermocouples. Calibration line of H2 concentration calculated by the least square method is linear and standard error (SE), 0.44 vol%, is smaller than measured value.

Optical scattering spectra and angular distribution of scattering intensities were evaluated using concentrated orange juice. The concentrated orange juice was opaque due to the scattering particles included. In these specimens, the scattering intensities and angular distribution of the scattering intensities varies with the refractive index ratio of the scattering particles against the liquid surrounding the particles. The sugar concentrations of orange juice, which are linearly correlated with the refractive index of the specimens, can therefore be measured by the scattering intensities and their angular distributions. The scattering intensities measured using a halogen lamp, a white LED, a yellow LED, a red LED and near-infrared LEDs (λ = 850 nm and 940 nm) vary linearly with the sugar concentrations of the specimens. The gradient and correlation coefficient of the calibration lines fitted are found to vary with the scattering angles, θ. A non-destructive evaluation of the sugar concentrations of orange juice can be measured sensitively at θ = 170 or 160 °s with any incident lights which are scattered from the specimens.

The ultraviolet C rays (UVC, wavelength λ = 100–280 nm) light generated by a Hg lamp ( λ = 254 nm) and UVC light-emitting diodes (LEDs, λ = 265 and 275 nm) was detected using a fluorescence-enhanced silicon photodiode (FE-PD). Ce-doped yttrium aluminum garnet (YAG:Ce), YAG:Pr, YAG:Eu, YAG:Tb, YAG:Cr, Al2O3:Ti, Al2O3:Cr, MgAl2O4:Ti, MgAl2O4:Cr, MgAl2O4:Mn, and commercial fluorescent acrylic resins were tested as phosphor sources to enhance the output signal intensity of the FE-PD irradiated with UVC light. The resulting output signal intensity increased linearly with the UVC light strength, which was adjusted by raising the input current of the UVC LEDs from 0 to 40 mA. The sensitivity of the fabricated UVC detectors, assessed based on the calibration curve slope, varied depending on the phosphor materials. The phosphors effectively enhanced the output signal intensity of the FE-PD, which was up to six times greater than that of the visible and near infrared Si-PD without phosphors; the stronger output signal intensity was achieved using YAG:Tb, YAG:Cr, and a red fluorescent acrylic resin. The visible light emitted by phosphors under UVC irradiation is useful for detecting UVC light by the eye when using FE-PD.

The next step for the generative adversarial networks (GAN) is to learn representations that allow us to control only a certain factor in the image explicitly. Since such a representation of the factor is independent of other factors, the controllability obtained from these representations leads to interpretability by identifying the variation of the synthesized image and the transferability for downstream tasks by inference. However, since it is difficult to identify and strictly define latent factors, the annotation is laborious. Moreover, learning such representations by a GAN is challenging due to the complex generation process. Therefore, we resolve this limitation using a novel generative model that can disentangle latent space into the appearance, the x-axis, and the y-axis of the object, and reassemble these components in an unsupervised manner. Specifically, based on the concept of packing the appearance and location in each position of the feature map, we introduce a novel structural constraint technique that prevents these representations from interacting with each other. The proposed structural constraint promotes the disentanglement of these factors. In experiments, we found that the proposed method is simple but effective for controllability and allows us to control the appearance and location via latent space without supervision, as compared with the conditional GAN.

Rendering an any-viewpoint image is extremely difficult for Generative Adversarial Networks. This is because conventional GANs do not understand 3D information under-lying a given viewpoint image such as an object shape and relationship between viewpoint and objects in 3D space. In this paper, we present how to perform a Viewpoint-Agnostic Image Rendering (VAIR), equipping a conditional GAN with a mechanism to reconstruct 3D information of the input view. VAIR realizes any-viewpoint image generation by manipulating a viewpoint in 3D space where the reconstructed instance shape is arranged. In addition, we convert the reconstructed 3D shape into a 2D representation for image-based conditional GAN, while preserving detail 3D information. The representation consists of a depth image and 2D semantic keypoint images, which are obtained by rendering the shape from a viewpoint. In the experiment, we evaluate using a CUB-200-2011 dataset, which contains few-samples biased a viewpoint such that covers only part of the target appearance. As a result, our VAIR clearly renders an any-viewpoint image.

Obtaining context information in a scene is an essential ability for semantic segmentation. GloRe [1] learns to infer the context from a graph-based feature constructed by the Global Reasoning unit. The graph nodes are features that are segmented into regions in image space, and the edges are relationships between nodes. Therefore, a failure to construct the graph results in poor performance. In this study, to resolve this problem, we propose a novel unit to construct the graph using multi-scale information. We call it Multi-scale Global Reasoning Unit. It considers the relationship between each region that retains detailed multi-scale spatial information. Specifically, the proposed unit consists of a Feature Aggregation Module and a Global Reasoning Module. The former selects the features required to construct the graph using the multi-scale features. The latter uses GloRe to infer the relationship from the features. The unit is trained in an end-to-end manner. In experiments, we evaluate the effectiveness of the proposed method on Cityscapes and Pascal-context datasets. As a result, we confirmed that the proposed method outperforms the original GloRe.

In this paper, we propose convolutional neural networks for semantic segmentation on road markings in the situation where sequential segmentation ground truth masks are available. The proposed model aggregates the temporal information and the context information from the multiple frames. Moreover, we employ CGNet as the backbone network to reduce trainable parameters and computation speed. In the experiment, we evaluate the model using the Gifu-city Road Marking Segmentation Dataset, which includes road markings of open roads in Gifu city. As a result, the segmentation performance such as a white center line and white dash line is an improvement.

Mn doped spinel (MgAl 2 O 4 ) crystals have been grown by floating zone (FZ) techniques with various conditions of O 2 concentrations in the growth atmosphere from 0 to 75 vol%, with a starting composition of molar ratio x= MgO/(MgO+Al 2 O 3 ) from 0.3 to 1.0 and/or Mn concentrations from 1.0 to 6.0 at%. Optical absorption spectra and photoluminescence spectra were evaluated using crystals grown under various growth conditions. The color of the crystals is found to vary with their composition and the O 2 concentration in the atmosphere. Crystals grown under a 100 vol% Ar atmosphere, were a pale green color and emitted a strong green luminescence at λ =520 nm. Colors of stoichiometric crystals, x =1.0, and Mg-poor crystals grown under an oxidizing atmosphere are yellow and red, respectively. Both optical absorption spectra and photoluminescence spectra of Mg-poor, x 2 –Ar) atmosphere are found to vary greatly from those of the stoichiometric crystals.

Anomaly detection is a challenging and fundamental issue in computer vision tasks. In recent years, GAN (Generative Adversarial Networks) based anomaly detection methods have achieved remarkable results. But the instability of training of GAN could be considered that decreases the anomaly detection score. In particular, Bi-directional GAN has the following two causes that make the training difficult: the lack of consistency of the mutual mapping between the image space and the latent space, and the difficulty in conditioning by the latent variables of the image. Here we propose a novel GAN-based anomaly detection model. In our model, we introduce the consistency loss for ensuring mutual mappings. Further, we propose introducing the projection discriminator as an alternative of concatenating discriminator in order to perform efficient conditioning in the Bi-directional GAN model. In experiments, we evaluate the effectiveness of our model in a simple dataset and real-world setting dataset and confirmed that our model outperforms the conventional anomaly detection methods.

Designing the optimal architecture of neural networks is an important issue. However, since this is difficult even for experienced experts, automatic optimization of the network architecture is required. In this study, we regard this issue as a combinatorial optimization problem, and utilize genetic algorithm to optimize the network architecture. Because training the networks, which are represented by individuals in GA, takes a long time, a novel method to reduce the training time by inheriting the weights of the trained network is proposed. From experimental results, our proposed method achieved the time reduction and higher accuracy than a conventional method.

We propose a defect detection method of solders on a printed circuit board using X-ray CT inspection system and Adversarial Autoencoder (AAE)[1] . We obtain sliced images of the solder using X-ray CT and extract their features that follow the standard normal distribution by using AAE. Then, the solder defects are detected by Hotelling's T square[2]. As a result of experiments, we show that we can classify normal and anomalous data samples completely on the condition of training with large normal samples and small anomalous samples.

X-ray excited visible light luminescence were evaluated from Cr doped Y3Al5O12 (YAG) crystals using an X-ray powder diffractometer adapting a fiber spectrometer, a digital camera, and a LED illumination. Red colored luminescence peaking at λ = 678, 690, 708, and 726 nm were observed from Cr doped YAG under irradiation by both CuKα X-ray and a violet LED (λ = 405 nm). Peak wavelengths of X-ray excited luminescence are the same as those of photoluminescence (PL). The peak intensities of X-ray excited luminescence, which increases linearly with X-ray strength, increases up to Cr concentration at around 0.5 mol%, then decreases gradually with Cr concentration due to a concentration quenching. It was found that the concentration quenching of X-ray excited luminescence occurs at a lower concentration at around 0.5 mol% than that of PL at around 3.5 mol%.

A fluorescent temperature sensor using temperature dependence of fluorescent inorganic materials is studied for low temperature measurement. Ruby (chromium ions doped sapphire) is used as a sensor head of the fluorescence thermometer because of long photoluminescence (PL) lifetime and visible emission. In this research, ruby crystal is found to be useful as the sensor head for fluorescence thermometer. In addition, the ruby crystal is potentially useful material for the sensor head crystals to measure low temperature below 0 °C.

Concentrations of vitamin B2 in milk were evaluated based on photoluminescence (PL) peak intensities at around λ = 545 nm. PL was measured in a back-scattering configuration using a 3.2 mm diameter optical fibre bundle irradiated by ultra-violet LEDs, violet LEDs or a blue LED as the excitation light. The tip of the optical fibre bundle was dipped into commercially available whole milk, low-fat milk and non-fat milk. PL peaking at 545 nm was observed under LED irradiation. Vitamin B2 concentrations were measured using a standard addition method and a calibration curve method. Deviation between the vitamin B2 concentration measured by PL using a standard addition method and those by HPLC technique varied with wavelength of excitation light and was smallest with violet LED (405 nm) excitation. The standard deviation of results measured by PL using a calibration curve method was better than those using a standard addition method.

Optical back-scattering from milk with various fat and protein concentrations were evaluated in a back-scattering configuration using white, violet, blue, green, red or near infrared (NIR, λ = 850 and 940 nm) LEDs as the light source. The tip of the optical fibre bundle was dipped into the milk with fat and protein concentrations from 8.2 to 39 g L−1 and 32 to 37.7 g L−1, respectively. The back-scattering intensities varied linearly with the fat and protein concentrations of the milk. The slope (G) of calibration lines varied with the wavelength of the incident light. The G of the fat concentrations became zero at wavelength around λ = 520 nm and that of the protein concentrations was much smaller than that of the fat concentrations at NIR wavelengths. The fat and protein concentrations can therefore be measured separately based on the scattering intensities by selecting the wavelength for measurement.

As corals in tropical regions are threatened by increasing water temperatures, poleward range expansion of reef-building corals has been observed, and temperate regions are expected to serve as refugia in the face of climate change. To elucidate the important indicators of the sustainability of coral populations, we examined the genetic diversity and connectivity of the common reef-building coral Acropora hyacinthus along the Kuroshio Current, including recently expanded (

The inspection of solder joints on printed circuit boards is a difficult task because defects inside the joints cannot be observed directly. In addition, because anomalous samples are rarely obtained in a general anomaly detection situation, many methods use only normal samples in the learning phase. However, sometimes a small number of anomalous samples are available for learning. We propose a method to improve performance using a small number of anomalous samples for training in such situations. Specifically, our proposal is an anomaly detection method using an adversarial autoencoder (AAE) and Hotelling’s T-squared distribution. First, the AAE learns features of the solder joint following the standard Gaussian distribution from a large number of normal samples and a small number of anomalous samples. Then, the anomaly score of a solder joint is calculated by Hotelling’s T-squared method from the features learned by the AAE. Finally, anomaly detection is performed by thresholding using this anomaly score. In experiments, we show that our method performs anomaly detection with few false positives in such situations. Moreover, we confirmed that our method outperforms the conventional method using handcrafted features and a one-class support vector machine.

Luminescence properties of Mn doped MgAl

In this paper, we discuss a method to detect defects in industrial products by using Denoising AutoEncoder Generative Adversarial Networks. In previous methods, a defective area is detected by restoring a defective product image which added an artificial defect to a non-defective product image by Denoising AutoEncoder (DAE). Therefore, a defective area is detected by subtracted image of them. We discuss whether further accuracy improvement is possible by introducing a framework of adversarial learning to DAE in order to restore a defective image to a non-defective image clearer.

A novel thermoelectric type hydrogen gas sensor based on exothermic reaction of hydrogen storage alloy is proposed and fabricated. First, an exothermic reaction of a hydrogen storage alloy at room temperature has been studied for a hydrogen gas sensor application. Next, a copper (Cu) constantan thermocouple painted a palladium (Pd) past on surface was fabricated as a hydrogen gas detector. The response characteristic of the fabricated hydrogen gas detector was evaluated under hydrogen gas flow. The exothermic reaction of Pd and hydrogen gas was successfully observed using fabricated gas detector. It was clarified that the fabricated hydrogen gas detector using Cu constantan thermocouple with Pd is potentially useful for hydrogen gas sensor material.

Spinel (MgAl 2 O 4 ) crystals doped with 1.0% Mn have been grown by floating zone (FZ) technique with various Mg compositions, x = MgO/Al 2 O 3 , from 0.2 to 1.0. Compositional variations of photoluminescence are evaluated for a fluorescence thermometer application using crystals grown. Strong photoluminescence (PL) peak is observed at λ from 512 to 520 nm from the crystals grown from compositions, x , from 0.3 to 1.0. Peak wavelength of PL increases linearly from 512 to 520 nm with x . Weak PL peaking at λ = 750 nm is also observed from the specimens. Compositional variations of PL are considered to be due to the variation of crystal field surrounding the Mn 2+ ions. The variation of crystal field strength agrees with the compositional variation of lattice constant.

Eu 2 O 3 doped Y 3 Al 5 O 12 (YAG) crystals have been grown using a floating zone technique and evaluated thermal stability and annealing behavior of PL for a fluorescence thermo-sensor application. Color of the crystals grown varies from deep purple to colorless with O 2 concentration of the growth atmosphere and annealing in air. Photoluminescence (PL) peaking at λ = 590, 607, 624, 647 and 709 nm due to Eu 3+ ions are observed from the crystals under UV excitation. Anomalous temperature dependence of PL intensity, which is observed in as-grown crystals, is improved greatly by annealing through the heat cycle. From annealing behavior of optical absorption spectra, residual Eu 2+ ions are suggested to be responsible for the de-coloration and the improvement of anomalous temperature dependence of Eu doped YAG crystals.

Red colored bright visible light fracto-mechanoluminescence was observed successfully from ruby (Cr doped Al2O3) and Cr doped spinel (Cr doped MgAl2O4) crystals in mechanical processes such as cutting, grinding and polishing. Fracto-mechanoluminescence spectra from ruby (peaking at λ=696 nm) and Cr doped spinel (peaking at λ=693 nm) perfectly agree with those of photoluminescence (PL) from Cr3+ ions in ruby and spinel crystals, respectively. In the grinding and polishing processes, peak intensities and peak wavelength of fract-mechanoluminescence from ruby and Cr doped spinel crystals varies with roughness (grain size, #) of the diamond disk. Fracto-mechanoluminescence is expected to be used in the in-situ evaluation of fracture of crystals in cutting, grinding and polishing for highly precise mechanical processes.

Photoluminescence and visible light thermal radiation from Eu, Al doped SiO 2 (SiO 2 :Eu, Al) glass fiber have been studied for a fiber-optic thermometer application. Photoluminescence (PL) peaking at λ =433, 485 and 617 nm is clearly observed from SiO 2 :Eu, Al glass with UV excitation ( λ =365 nm). Peak intensity of PL decreases with temperature form 300 to 1000 K. Visible light thermal radiation peaking at λ =660 nm is also observed from SiO 2 :Eu, Al glass above 1000 K. Peak intensity of visible light thermal radiation increases exponentially with temperature. Temperature can be measured based on temperature dependences of PL (below 1100 K) and visible light thermal radiation (above 1000 K) using SiO 2 :Eu, Al glass fiber. The hybridization of fluorescence thermometry (below 1000 K) and thermal radiation thermometry (fiber-optic pyrometer, above 1000 K) using SiO 2 :Eu, Al glass fiber is thought to extend the temperature range of a fiber-optic thermometer.

Photoluminescence spectrum, trap depths, and densities of trapped carriers of CaAl2O4:Eu phosphor crystals doped with rare-earth elements were studied using the thermally stimulated luminescence technique. Trap depths and densities of the specimens vary with rare-earth elements doped as the auxiliary activators. Tm and Nd are found to be effective for the strong afterglow phosphorescence peaking at λ = 442 nm for several hours after the excitation. CaAl2O4:Eu phosphor crystals doped with Nd and Tm include high density of carriers trapped at E = 0.59 and 0.52 eV, respectively.

Optical scattering spectra and angular distribution of scattering intensities were evaluated using commercially available tomato juice for a non-destructive quality control. A halogen lamp, a red LED and NIR LEDs (λ = 850 nm and λ = 940 nm) can be used as the incident light for scattering evaluations of tomato because incident light with wavelengths shorter than 550 nm is absorbed by pigments in tomato. Scattering intensities and their angular distributions are found to depend on the sugar concentrations of tomato juice. The scattering intensities vary linearly with the sugar concentrations of the specimens irradiated with a halogen lamp, a red LED or NIR LEDs (λ = 850 nm and λ = 940 nm). Gradient of calibration lines, G, between the sugar concentrations and the scattering intensities varies with the scattering angles and the wavelength of light irradiated. G is large negative value with large scattering angles such as a back scattering configuration. While, G is small positive value with small scattering angles such as a forward scattering configuration.

Equipment for the non-destructive evaluations of a tomato has been developed based on the scattering spectra, the angular distributions of the scattering intensities, and the scattering images from the specimens. The sugar concentrations of tomato can be estimated optically based on the scattering intensities using a halogen lamp, a white light-emitting diode (white LED), a yellow LED, a red LED, and near infrared LEDs (λ = 850 nm and 940 nm) as the incident lights. The scattering intensity is found to vary linearly with sugar concentrations of tomato with any wavelengths at which the scattering light can be observed. The gradient of calibration lines of the sugar concentrations against the scattering intensities varies with scattering angles, θ. Evaluations at around θ = 160° are found to be suitable because of the large gradient and good linearity with the correlation coefficient, R, close to 1.

Thermo-sensor characteristics of Cr doped YAlO3 composite with silicone resin have been evaluated based on the temperature dependence of photoluminescence intensity from the specimens. Photoluminescence (PL) peaking at wavelengths, λ = 725, 732 and 748 nm are observed from the composite sensor with an excitation by green colored LED at λ = 536 nm. PL peak intensities and peak intensity ratio varies sensitively with temperature. Silicone composite sensor with 50 wt% of 0.2 at% Cr doped YAlO3 powders is found to be useful sensor for fluorescence thermometer, because of the large temperature coefficient and good repeatability of PL intensity ratio.

Luminescence properties of Mn doped MgAl2O4 crystals connected with the Si PIN photodiode (PD) have been evaluated for X-ray detector applications. Mn doped MgAl2O4 crystals emit green colored luminescence peaking at around λ = 520 nm with CuKα irradiation. The intensity of the output signal from Si PD increases linearly with the X-ray intensity of CuKα generated with the X-ray tube at a current from 2 mA to 40 mA. The intensity of the X-ray excited luminescence is strongest in the specimen with 3.0 mol. % Mn. Afterglow luminescence is weak in the specimen with 2.0 mol. % Mn. Mn doped MgAl2O4 crystals connected with the Si PD is considered to be a useful X-ray detector.

A new compound having a 2,3,4,5-tetraphenylsilole derivative on the center silicon of Dumbbell(1)6Gb3; Silole-Dumbbell(1)6Gb3 (1) was previously reported. It was found that 1 exhibited strongly increased fluorescence both in water and in a 96% acetone/water mixed solvent. The physical behavior of 1 in water and in the 96% acetone/water mixed solvent was investigated, and analyses including fluorescence quantum yields, dynamic-light-scattering (DLS), atomic-force-microscopy (AFM), and fluorescence microscopy were carried out. It was clarified that 1 dynamically formed different types of aggregates in water and in higher acetone concentrations to yield high aggregation-induced emission (AIE) effects due to the formation of micelle-like particles in water and inversion-type micelles in the acetone/water mixed solvent, respectively.

A glycocluster peripherally functionalized with a lactose (Lac: Galβ1→4Glcβ1–) derivative possessing a silole moiety as a luminophore was synthesized. The photoluminescence spectrum of the glycocluster showed extremely strong emission at 474 nm and the absolute quantum yield was estimated to be 92% in distilled water. The emission intensity was decreased by increasing the amount of peanut agglutinin (PNA), a lactose-binding lectin, and plots of the relative fluorescence intensity revealed a decline of 95% in emission intensity. Fluorescence quenching of the glycocluster upon mixing with PNA could be easily observed by the naked eye under UV irradiation, whereas no distinct change in fluorescence properties of the glycocluster was observed when wheat germ agglutinin (WGA) was employed.

In this article, vehicle dynamics integrated control algorithm using an on-line non-linear optimization method is proposed for 4-wheel-distributed steering and 4-wheel-distributed traction/ braking systems. The proposed distribution algorithm calculates the magnitude and direction of tire forces, which satisfy constraints corresponding to the target resultant force and moment of the vehicle motion and which minimizes maximum μ rate (=tire force/friction circle) of each tire. Convexity of this problem is shown, so that the global optimality of the convergent solution of the recursive algorithm is guaranteed. This implies that theoretical limited performance of vehicle dynamics integrated control is clarified. The proposed algorithm is based on SQP (Sequential Quadratic Programming) and steepest gradient algorithm. Calculation speed performance of the proposed algorithm is shown in comparison with primal-dual interior-point method, which is representative optimization method. Furthermore, the effect of this vehicle dynamics control is demonstrated by simulation and experiment to compare with various vehicle dynamics integrated control methods.

A novel glycocluster periphery functionalized by globotriaose (Galα1–4Galβ1–4Glcβ1–) possessing a silole moiety as a luminophor was synthesized. The photoluminescence spectrum of the glycocluster in pure water showed extremely strong emission at 475 nm. Analogous intense emission of the silole dendrimer was also observed in a lower water fraction of water/acetone mixture. The water fraction of the silole dendrimer solution strongly affected the emission intensity; however, these luminescences were constantly detected at around 475 nm.

Rare-earth aluminate crystals have chemical and thermal stability, which are advantage for the sensor materials of a fiber-optic fluorescence thermometer. Among many rare-earth aluminate crystals, rare-earth garnet, Y 3 Al 5 O 12 , doped with Cr 2 O 3 (Cr-doped YAG), is found to be useful as the sensor materials for fluorescence thermometer. Fluorescence lifetime of Cr-doped YAG crystal decreases from 2 ms to 0.1 ms as the temperature increases from 273 K to 900 K. Moreover, thermal radiation from Cr-doped YAG crystal can be observed from 800 K using Si photo-detector. The fiber-optic thermometer with extremely wide temperature range is considered to be produced by the combination of the temperature dependence of the fluorescence lifetime and the thermal radiation from Cr-doped YAG crystal.

BaAl 2 O 4 :Eu,Dy (BAO) films have been fabricated on Si substrate by laser ablation, and their fundamental optical property and afterglow characteristics are discussed in comparison with the SrAl 2 O 4 :Eu,Dy (SAO) films. The intense green emission near 500 nm that originates from 5d to 4f transition in Eu 2+ ions was clearly observed from the BAO films. This photoluminescence peak was at a shorter wavelength than that of the SAO films (λ=520 nm). The afterglow intensity from the BAO films disappeared within a few minutes whereas that of the SAO films lasts over 20 min. The hole-trap depth (E t ) created by Dy as the auxiliary activators, which strongly affects the afterglow characteristics, was estimated on the basis of the thermally stimulated luminescence (TSL) result. The TSL glow curve for BAO films showed two broad peaks at 320 K and 450 K. The calculated E t for each peak was 0.2 eV (for the 320 K peak) and 1.2 eV (for the 450 K peak). On the other hand, E t =0.5 eV was obtained from the SAO films. The hole-trap depths of the BAO film are either too shallow or too deep to affect the afterglow characteristics at room temperature.

Terbium ion (Tb 3+ ) doped silica glass (Tb:SiO 2 ) and yttrium aluminum garnet crystals (Tb:YAG) have been fabricated for the applications in fiber-optic thermometers based on the temperature dependence of the photoluminescence (PL) spectrum. Several PL peaks at 490, 540, 585, 625 nm were observed from both Tb doped phosphors. In Tb:YAG crystal, the PL peaks were split into two or three small peaks due to the Stark effect. Temperature dependence of PL spectra from Tb:SiO 2 glass and Tb:YAG crystal was evaluated over a temperature range from 300 to 1200 K. In the Tb:SiO 2 glass, the peak PL intensity varied greatly with temperature. The shape of the PL spectrum from Tb:YAG crystal varied with temperature because the resolution of the split in the peak PL decreased with temperature. The intensity ratio between splitting PL peaks, therefore, varied with temperature. From these results, Tb:SiO 2 glass and Tb:YAG crystals are considered to be a useful sensor head materials for high temperature measurement using temperature dependence of PL intensity.