Globally, Critical Metals have become a focus in many countries and jurisdictions. While the primary production of Rare Earths has been highlighted, other less known but even more Critical Metals from primary and secondary sources have also been studied. At the Kroll Institute for Extractive Metallurgy, KIEM, much of the research effort is currently focused upon either the primary or secondary production of Critical Metals.In addition, the key underlying aspect of Criticality is also being addressed in the form of the development of desperately needed technically skilled personnel and technologies which are increasingly in demand. This paper will outline aspects of these topics.

Copper sulfide from ore deposits and recycled copper from collected wastes are the two main resources for the production of copper metal. Thermodynamic calculations can be used to serve as a guide for characterization of ore deposits and their mineralogy as well as for process development by mineral processing and by waste separation. The concentrated ore and separated waste can then be processed by pyro- and/or by hydro-metallurgical operations. Such operations may be controlled by oxidation-reduction potential, temperature, complexing reagents (gas, solid or dissolved species), oxidant- reductant, and mass of components. Commonly used stab ility diagrams for aqueous system include speciation (counting alpha) and E_H-pH (Pourbaix) diagrams and, for non-aqueous systems, are partial pressure (Kellogg), binary and ternary phase, and Ellingham diagrams.

For multicomponent systems, the appropriate approach for the construction of the stability diagram is to use a complete mass balance approach rather than draw the equilibrium line between two adjacent species. Not limited to two variables, a three- dimensional diagram can also be constructed.

This paper illustrates the use of stability diagrams for investigating and interpreting how operation variables are important with a focus on extractive metallurgical operations to produce copper. Industria l operation conditions are marked on the diagrams.

While getting a haircut at a hairdresser's, a customer may be unable to effectively communicate his or her hair-related needs. Additionally, the hairdresser often does not share an accurate final image of the customer's hairstyle even with the use of a hair catalog. Head shapes differ for each individual, which implies that the customer's head shape would be different from that of a catalog model. Often, the customer's expectations of the desired hairstyle and the practical results are different. If the final image of the customer's haircut is presented using a 3D hair simulator beforehand, it would facilitate the sharing of hair-related needs between the customer and the hairdresser, thereby improving customer satisfaction. In our previous study, we proposed a basic simulation method that took into consideration the head model generation method and the hairdresser's cutting technique. However, the study did not adequately consider the operability, such as the adjustment of hair in the simulator. Therefore, in this study, we developed a 3D hair simulator to provide support for hairdressers. In particular, we improved the interface for adjusting hair length and evaluated the operability improvement.

The composite negative electrode active material of Li-ion batteries (LIBs) was fabricated using phenolic resin (PR) and agricultural waste of rice husk (RH). Because silicates were intrinsically composed in RH, the composite of hard carbon (HC) and SiO_x (HC/SiO_x composite) was readily prepared by carbonizing the mixture of PR and RH. Li-ion insertion and extraction capacity of the HC/SiO_x composite was evaluated in a half-cell configuration using Li metal as the counter electrode, in comparison with those of the carbonized RH and the commercial HC. It was revealed the HC/SiO_x composite exhibited 30% higher specific capacity of Li-ion insertion/extraction than did the commercial HC. In addition to this, its capacity retention was found to be approximately equal to that of the commercial HC. The performance comparison of the HC/SiO_x composite and the carbonized RH suggested that hybridization of HC and SiO_x was useful to alleviate the capacity fading of the SiO_x part with maintaining the increased specific capacity attributed to the SiO_x part. Cost-effective active material for the LIB negative electrode with acceptable performances could be realized by the simple carbonization of the mixture of PR and RH. The produced HC/SiO_x composite was promising for vehicle applications requiring excellent cycle performance and high cost effectiveness.

In Japan, “Fiber-cement-stabilized soils method” (FCSS) has studied and applied to recycle dredging sludge from rivers and canals. The method mixed paper fragment and cement into the dredging sludge. The modified-sludge showed some advantages, such as high strength, high durability, friendly environment, and inexpensive. In this paper, FCSS is applied to recycle dredging sludge in Vietnamese Mekong delta. Nevertheless, the cost of paper fragment is becoming too high and also it is difficult to obtain in the delta. Local fiber is strongly desired in order to reduce the recycling fee. Therefore, rice straw is utilized due to its plenty and wasteful amount in Vietnamese Mekong delta. If the paper fragment can be replaced by the rice straw as fiber material, the modified-sludge will be promising able to recycle by FCSS. In this study, unconfined compression tests were carried out to investigate the strength and strain characteristics of the rice straw fiber-cement-reinforced sludge. The results indicated that the rice straw could be used instead of paper fragment in FCSS with high mechanical performances. Moreover, empirical functions were obtained to predict the optimum values for rice straw content and cement content.

A low-rate denial of service (LDoS) attack can degrade the quality of TCP communication with fewer attack traffic. The LDoS attack transmits such network traffic that conforms to the minimum value of TCP retransmission timeout. This provides periodic features to the traffic concerned. We consider the application of an R/S Pox Diagram characteristic which can represent the LDoS attack periodicity. An R/S Pox Diagram shows a characteristic plot shape against the periodicity of the LDoS attack. The distinct shape of the plot is quantified as shape features of the two-dimensionally imaged R/S Pox Diagram. Our proposal in this paper is to positively make use of the shape features of the two-dimensionally imaged R/S Pox Diagram. We show the effectiveness of the shape features utilization by showing their detection performance to pieces of simulating LDoS attack.

Nano bubbles are prepared by using a pressurized pump or fine ceramics in water or oil. The prepared nano bubbles are stable for more than several days. Nano emulsion (w/o type) is prepared by mixing oil, water and surfactant with homogenizer and stable more than several months. The prepared bubble and emulsion size distribution in liquid is usually measured by dynamic light scattering method. However, it is difficult to measure the particle size for smaller refractive indexes between dispersed particle and solvent by the light scattering method and small amount of particle volume. Here, the dynamical method of interactive force measurement between dispersed nano bubble and emulsion under electric field has been used to measure any kind of small particle size distribution.

Elderly care is an important requirement in an aging society. Video chat has been used as a support tool to watch over elderly people from remote places. Caregivers can check the conditions of elderly people through video chat. However, in a video chat, because a camera captures information on activities and things present in the room, the potential leakage of private or confidential information is of great concern. Therefore, in order to improve the security and quality of life, it is necessary to protect privacy in using video chat to monitor elderly people. To that end, it will suffice to extract only a person from the camera image in real time and replace background information with a predetermined image. In addition, background replacement can improve the extraction accuracy of a person by using a monochromatic background such as a chrome frame processing. When assuming use in daily life, it is necessary to extract people from the various objects located in the living space, without using background papers. In this paper, we propose a background replacement method for privacy protection in the elderly care system with regard to person extraction during video chat.

Rice hull which is one of the agricultural wastes in Japan has been demanded to reuse as the industrial materials. Rice hull silica carbon (RHSC) material, made from rice hull is produced by mixing rice hull powder with a phenol resin, and then carbonizing and the mixture in the nitrogen gas atmosphere at high temperatures. The RHSC is a porous carbon material utilizing natural porous structure originated from the rice hull. Therefore, reduction in environmental pollution is expected by the RHSC which is inexpensive and unique. In addition, a core competence of low friction coefficient, lubrication free, and high water resistance was reported for the RHSC in previous research. However, the RHSC has low reliability of strength originated potentially from the porous structure. Since the reliability of the RHSC is evaluated by a fatigue test which is required several weeks, calculating the fatigue strength by simulation analysis is useful. In this study, fatigue strength simulation analysis in natural porous structure was figured out and the size effect which influences the strength of the material was investigated.

Two thiocarbamoyl compounds, monomer-type 4-tert-butyl(dimethylthiocarbamoyloxy) benzene (1) and dimer-type 1,1'-bis[(dimethylthiocarbamoyl)oxy]-2,2'-thiobis[4-t-butylbenzene] (2), were impregnated on ambertite XAD-7 resin for selective recovery of palladium from platinum group metals (PGM) containing a HCl solution. Pd(II)-ion adsorption performance of 1 and 2 impregnated resins were carried out in batch mode by varying HCl concentration, shaking time, Pd(II) concentration, and adsorbent amount. The monomer-impregnated adsorbent showed high Pd(II) sorption (94.1%) as compared with dimer-impregnated adsorbent (74.4%) in 1 M HCl media. Both monomer- and dimer-impregnated adsorbents exhibited a selective Pd(II) sorption from a mixed solution of PGM (Pd, Pt, and Rh). Pd(II)-ion desorption from Pd(II) adsorbed adsorbents were carried out using HCl-thiourea mixture as a desorption reagent. The results showed that both resins were suitable for selective separation of Pd(II) from PGM secondary resources.

The Arakawa deposit is a Miocene vein-type copper deposit in the Northeast Japan arc. The ore minerals from the deposit were analyzed by a scanning electron microscope with energy dispersive X-ray spectroscope and/or an electron probe micro analyzer. Bismuth and tellurium minerals we found from the ores are bismuthinite, tetradymite, hessite, tsumoite, pavonite, matildite, and ourayite. Bi/Te(＋Se＋S) of bismuth-tellurides of the Arakawa deposit are ≤ 1. This composition indicates a relatively high sulfur and tellurium fugacity conditions of the ore forming fluid. It also shows an oxidized environment, close to the hematite-magnetite buffer. Bismuth mineral assemblage of the Arakawa deposit is similar to the other Miocene vein-type copper deposits in the Northeast Japan arc.

Human eyes can perceive two different colors as a single blended color when they are switched at a high speed. If this characteristic is used to display an image on a Liquid Crystal Display (LCD), the color of the image perceived will differ from the color that is captured on the LCD screen. Thus, this display method can be expected to deter illegal copying of images. However, the flicker occurs only when two colors with different levels of brightness are switched. We have already studied whether flicker was felt under the conditions of different switching speeds and using combination of two grayscale images. The experiment established that the flicker can be reduced at a switching speed of 144 Hz and combinations with gradation values of 0-127 and 191-255. However, the condition for reducing the flicker when using grayscales of gradation values 127-191 was not clear. In addition, conditions for reducing the flicker when using other colors have not been clarified. Therefore, to clarify the condition for reducing the flicker, we examined if flicker was felt with the combination of two grayscale images, gradation values of which were split in increments of eight from 127 to 191. Furthermore, we evaluated whether flicker was perceived or not under the conditions obtained from the grayscale experimental results when the same system colors were switched. As a result, we identified the conditions that make it possible to reduce the flicker that occurs when switching the same system color.

In a previous study, we clarified that the presence or absence of amusement can be detected by focusing on the variation of movement features of the lip. When a strong emotion is evoked, some body movements are observed in the head and shoulders. Based on these findings, it is possible to quantify human emotion accurately by combining facial expressions, movement of lips, and body movement features. Therefore, we attempted to quantify amusement by acquiring three-dimensional data of head and shoulder movements while subjects were watching emotion-eliciting videos using Microsoft Kinect. In this study, we acquire head and shoulder movements as three-dimensional data and analyze the movements of the body when amusement is evoked. Thereafter, we label amusement and the normal state of a subject while watching the video. We also classify the amusement state and the normal state of the subjects using various machine learning methods (decision tree, random forest, XGBoost, support vector machine, linear, and neural network).

In power apparatus, it is essential to have insulating material with high resistance to damages. MoS₂ nanofiller can provide good mechanical, insulating and thermal properties. An attempt has been made to understand the resistance to damage of the material through surface discharge studies and it has been observed that addition of low weight percentage of MoS₂ has high resistance to surface discharges. The results are aided by surface charge accumulation studies. Characteristic variation in dielectric properties of the material indicates that low weight percentage addition of MoS₂ nanofillers shows a reduction in permittivity of the material and has low loss. It was observed that epoxy nanocomposites are resistant to water droplet initiated discharges. Corona inception voltage (CIV) with multiple droplets, droplet near high voltage and ground electrode were measured. It is interesting to note that, irrespective of the number or the position of water droplets and voltage profile, 0.5 wt% MoS₂ added epoxy shows high resistance to discharges. It was also observed that CIV reduces when two droplets placed in electrode gap and when the droplet is placed near the electrodes. Glass transition temperature (T_g) of epoxy/MoS₂ varies with fi ller loading. Optical emission spectroscopy (OES) results indicate that the plasma temperature is low for epoxy resin with 0.5 wt% MoS₂.

Landslide or landslip is one of the natural disasters which is unfortunately unavoidable. We have already established the Fiber-Cement-Stabilized Soil Method that can improve the weak soil of actual landslide areas engendered from an earthquake or heavy rainfall by using paper fragments and cement. However, nowadays, the cost of fiber (paper debris) is tending to increase and Portland cement is not environmentally friendly cementitious material for sustainable development. In this research, Geopolymer which expects to modify soft soil (sludge) at low degree Celsius condition and reduces amount additive of fiber is executed. The process of Geopolymerization involving the silicates and aluminates exacted from by-products is contemplated as a mature and cost-effective solution to many problems where hazardous residue has to be treated and stored under critical environmental conditions. This paper presents the details of the study carried out on the characteristic of sludge improved Fiber-Geopolymer-Stabilized Soil Method. The composition of imitation sludge was 60% silt, 40% clay and 70% water content. Sodium hydroxide (NaOH) 12 Molar and sodium silicate solution (Na₂SiO₃) were prepared. The test specimens were made of 50 x 100 mm cylindrical mold and 20℃ temperature curing condition. The result of modified sludge shows the improvement in strength, strain and high durability with drying and wetting tests regardless of the increase in experimenting rounds.

Waste asphalt blocks from construction sites are usually processed in the recycling plants to be used as recycled asphalt aggregates. These materials are usually fed into the grizzly to remove the soils attached on their surfaces. At present, grizzly-under-materials (GUM) does not satisfy the required standard value for soil contents. In 2009, we proposed the equipment to remove the soils from GUM. This equipment was able to reduce the soil content in the GUM, but the efficiency was not so high. Then, in 2013, a process of redesigning this equipment was carried out; where a vibration device was added to reduce the pipe inclination angle and to increase the processing time of materials inside the apparatus. The equipment performance had an opposite behavior from 2009's experimental results to 2013's experiment results, when the water content in the GUM was changed from 3% to 5%. That is, it was necessary to analyze the main factors that influence on equipment performance. In this study, the experiments were carried out with changing the water contents. It was found through this research that soil reduction activity, using the screenless separation equipment not only depends on the soil particle distribution (% of clay and silt) contained in GUM and the moisture content in the soil when is mixed with GUM. Specific surface area and water absorption of GUM and temperature also have influence on the mentioned activity.

In a previous study, we developed a method for classifying vegetation on a river bank managed by the Ministry of Land, Infrastructure, Transport and Tourism, by using images acquired from the Omonogawa River flowing through the Akita Prefecture. We focused specifically on color and texture information from those images, and proposed a method for classifying vegetation with a support vector machine, which is a pattern recognition model. However, the color features of the turf and the harmful vegetation, Fallopia japonica, were roughly the same when calculated during the same season across different years. Distinguishing images based on the acquired seasons should enable high-precision classification. Thus, in this study, we develop a learning data generation method that can classify new data. Specifically, we categorize the learning data by month and determine parameters for the appropriate unlearned data. An experiment is conducted using data generated from May, June, and July of 2015 and 2016. We found that the proposed generation method can classify river bank vegetation with high accuracy in comparison with the previous approach.

Cellulosic biomass such as wood waste and rice straw remains unexploited despite its high cellulose content. Streptomyces thermocarboxydus C42, which grows on cellulosic compounds including microcrystalline cellulose, was isolated from soil for genetic breeding of streptomycetes that produce antibiotics from cellulosic biomass. Draft genome sequencing revealed putative genes encoding nine cellulases and one xyloglucanase dispersed on the chromosome. All these genes were isolated and rearranged on a chromosome-integration vector for streptomycetes pTYM19 to construct cellulase-expression plasmids pBOM51 and pBOM66 for streptomycete host strains. The cellulase gene cluster on pBOM66 was further introduced into pTYM18, another Streptomyces integration vector, to yield pBOM67. To investigate cellulase secretion and antibiotic production, the resulting plasmids were introduced into Streptomyces avermitilis K139, the producer of avermectin and oligomycin. Remarkable cellulose-degrading activity for filter paper was observed by pBOM66-carrying transformants. Oligomycin alone was produced by the transformed strain with pBOM67 only when cultivated in a medium containing glucose: not in a medium containing microcrystalline cellulose as a carbon source. Using antibiotic-producing streptomycetes for antibiotic production from cellulosic biomass therefore appears to be infeasible, even when transformed with cellulase genes of Streptomyces origin.

For this study, we developed a novel real-time monitoring system using a stainless steel electrode to assess NaCl osmosis in the food interior by measuring electrical impedance. The NaCl penetration into agar gel sprayed with NaCl on the surface was evaluated using impedance. As the measured position of the electrode moves downward, a longer time is needed to obtain a constant impedance value. Measurement of the chloride concentrations in the model food that had been cut into four pieces (surface, upper, middle, and lower parts) revealed an extremely strong relation between the equilibrium period of the impedance value and the inner chloride concentrations of the model. Results confirmed that a similar impedance value was obtained if the concentration of NaCl sprinkled on the top of the gels was the same irrespective of points measured using the electrode. These results demonstrate that this impedance measurement method using an LCR meter is useful for real-time monitoring of NaCl osmosis in the food interior.

A series of 1,4-Dihydro pyrrole[3,2,b]pyrroles derivatives were synthesized to elucidate their structureproperty relationship and evaluate their feasibility as resistive memory elements. Smart structural modifications through judicious choice of functional groups was carried out to establish a rationale between molecular framework in a quadrupolar A-π-D-π-A configuration and its influence on the electronic and opto-electronic properties. The electrical switching characteristics of these materials have been evaluated by embedding them in a two-terminal metal-insulator-metal configuration and the results confirm that, the materials can mimic the functions of a permanent, rewriteable flash and dynamic-random access memories, which are expected to fulfil the requirements for low-cost flexible information storage applications.