Gas injection in metallurgical vessels is an important tool to improve chemical and thermal mixing. Chemical mixing has been extensively studied in the past 40 years, however, thermal mixing is still poorly understood. This work reports a mathematical model developed to describe the effect of the number and position of porous plugs on thermal and chemical mixing under industrial conditions.
A relevant contribution of this work is the evidence indicating a suppressing effect of bottom gas injection on thermal homogenization with off-center gas injection; furthermore, it also suggests that mixing time is optimized with only one nozzle instead of two or three.

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A statistical model for predicting the liquid steel temperature in the ladle and in the tundish is developed. Given a large data set in a steelmaking process, the proposed model predicts the temperature in a seconds with a good accuracy. The data are divided into four phases at the mediation of five temperature measurements: before tapping from the converter (CV), after throwing ferroalloys into the ladle, before and after the Ruhrstahl-Heraeus (RH) processing, and after casting into the tundish in the continuous casting (CC) machine. Based on the general state space modeling, the bootstrap filter predicts the temperature phase by phase. The particle approximation technique enables to compute general-shaped probability distributions. The proposed model gives a prediction not as a point but as a probability distribution, or a predictive distribution. It evaluates both uncertainty of the prediction and ununiformity of the temperature. It is applicable to sensitivity analysis, process scheduling and temperature control.

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ABSTRACT Objective: The purpose of this study was to investigate the characteristics of participants based on the differences in participation frequency in the selfdetermined participation type care prevention program. Methods: This study design was a cross-sectional study. Participants were 114 community-dwelling older adults aged 73.0 on median who were registered in the self-determined participation type care prevention program. Participants can freely decide the date of participation in this program. The exercise was performed depending on the ability of the participants. We evaluated program participation status, a higher-level functional capacity, grip strength, and walking speed. The higher-level functional capacity was evaluated using the Japan Science and Technology Agency Index of Competence (JST-IC). As an analysis, we first classified the frequency of participation into three groups: “less than once a week,” “1-2 times a week,” and “more than 3 times a week”, and compared the outcomes. Secondly, we investigated the relationship between participation frequency and four categories of the JST-IC. Results: Participants in the frequency of participation in “less than once a week,” “1-2 times a week,” and “more than 3 times a week” were 26, 76, and 12, respectively. The median scores of JST-IC were 13.0. There was no significant difference in JST-IC total, subscale scores and physical functions among the three groups based on the differences in participation frequency. Conclusion: In the population with high higher-level functional capacity, there was no significant difference in higher-level functional capacity and physical function based on the frequency of participation in the self-determined participation type care prevention program. It was suggested that a longitudinal survey was necessary after unifying the implementation period of the participants.

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Objectives: In an ultra-aged society, the increasing number of elderly individuals requiring nursing care because of complications and disabilities poses a significant challenge for healthcare providers, along with a decline in the quality of life (QoL). Therefore, investigating the underlying causes and establishing effective preventive measures is imperative. Sarcopenia, characterized by a reduction in muscle strength throughout the body, can negatively impact QoL because of declining physical function. This study aimed to elucidate the interrelationship between physical function and health-related quality of life (HRQoL) in elderly individuals requiring long-term care.

Methods: The participants (n=67) were elderly individuals (32 men, 35 women) requiring light nursing care. HRQoL was assessed using the EuroQol Group 5-Dimensions 5-Level (EQ-5D-5L) scale. Relationships between the EQ-5D-5L score and age, body mass index, SARC-CalF, and sex were examined. The relationships between the EQ-5D-5L score and the 10-s chair stand test, functional reach test (FRT), grip strength, 10-m walking test, and Timed Up-and-Go (TUG) test were investigated separately for men and women.

Results: A correlation was identified between EQ-5D-5L score and sex. In men, a correlation was identified between EQ-5D-5L and TUG test results. In women, a comparable correlation was observed between EQ-5D-5L score and the 10-m walking test, FRT, and TUG test.

Conclusions: The findings revealed a correlation between physical functions, including standing and walking, and QoL in elderly individuals requiring light nursing care. Maintaining and enhancing standing and walking abilities among this demographic group should be a high priority.

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We have designed and fabricated a tactile array sensors with three inclined micro-cantilevers embedded in elastomer, which can detect both normal and shear stresses. In this paper, we confirmed gripping status classification using sensor output. Using our sensor, four gripping status (free, grasping, holding and slipping) could be classified significantly.

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A laparoscopic surgery is performed through the incisions of 5 to 10 mm. Unlike an open surgery, which cut off big part of patient's body, laparoscopic surgery requires only small incisions. Therefore time and cost of post-operative care is dramatically reduced. There are down side of laparoscopic surgery also. Surgeon has to perform surgery with less dexterity and perception. The aim of this paper is to propose the mechanism of the forceps with additional freedoms at the tip of the forceps. Unlike the actual forceps, proposed forceps realizes freedom inside the body without using an actuator. This actuator free forcep is simple and easy compared to actuator driven forceps. With the proposed forceps, immediate action following an accident is possible.

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The purpose of this study is to develop a mathematical model to analyze the fluid flow phenomena of molten steel in the tundish during its filling stage and subsequent initial casting operation in the continuous casting process of steel. The ultimate goal is to assure smooth initial casting operation without nozzle clogging by avoiding high deposition rate of inclusion on any of the tundish outlets during tundish filling and subsequent initial casting operation.
The mathematical model is developed based on a computational fluid dynamics technique, named SOLA-MAC, and the k– ε two-equation turbulence model. SOLA-MAC technique has the ability to handle the flow problem encountered in tundish filling, which is a transient flow problem with highly distorted free surfaces and the locations of the free surfaces are to be determined by theory. A fluid particle method is also employed in this study to analyze the distribution of inclusions in the molten steel and the extent of inclusion contamination in various strands of the continuous casting tundish. A water model that is one-fourth the scale of an actual billet continuous caster is also constructed in this study. Water model experiments are conducted to verify the accuracy and reliability of the mathematical model.
The developed model is first tested on the water model to calculate the flow pattern of water in the tundish during the very early stage of filling operation. The simulated filling patterns are compared to the water model experiments. Good consistency is observed. The model is then tested on an actual billet continuous caster with four strands to simulate the fluid flow phenomena of molten steel in the tundish during the filling and subsequent initial casting operations. Inclusion distribution and the extents of inclusion contamination among the outlets of the various strands in the tundish are also analyzed. The simulated results show that for the left half of tundish, inclusion contamination in #2 strand is significantly more severe then that in #1 strand. This is confirmed by the actual experience on the shop floor of that particular billet caster that #2 strand experiences more difficulty in clogging problem during the initial casting operation than #1 strand does.

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In this paper, usability evaluation of a compact Braille reading sensor was carried out. Several sensors with different grips and guide components were fabricated. Using these sensors, sensory evaluation related to usability was conducted. At the same time, self- straitening characteristics of the sensors were evaluated by motion analysis. From the results, it was found that guide part with the groove width spreading toward the front of the sensor is effective for a usable sensor with high self-straightening characteristics, and it was suggested that the grip part should be designed to suit the preference of the user.

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Ore-based steelmaking generates various residues including dusts, sludges, scales and slags. Recycling of these residues within the process or via other applications is essential for sustainable production of steel. In blast furnace (BF) ironmaking, the gas-cleaning equipment generally recovers the particles in the off-gas as dust and sludge. Traditionally, the dry dust is recycled via the sinter or, in the case of pellet-based BF operation, via cold-bonded briquettes and injection. As the BF sludge mainly consists of iron and carbon, this residue is of interest to recycle together with the BF dust. However, depending on how the BF is operated, these two residues are more or less the major outlet of zinc from the furnace. Thus, to limit the recycled load of zinc, both materials cannot be recycled without dezincing the sludge prior to recycling. Dezincing and recycling of the low-zinc fraction of BF sludge via sinter have been reported whereas recycling via cold-bonded briquettes has not been performed. In the present study, cold-bonded briquettes containing the low-zinc fraction of dezinced BF sludge were charged as basket samples to the LKAB Experimental Blast Furnace (EBF). The excavated basket samples from the quenched EBF suggested that additions of up to 20 wt.% of upgraded BF sludge was feasible in terms of reducibility and strength. Based on these results, BF sludge were added to cold-bonded briquettes and charged in industrial-scale trials. The trials indicated that the annual generation of BF sludge, after dezincing, could be recycled to the BF.

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Sensory evaluation of the optimum diameter in grasping tennis racket and the grasping pressure at fingers and the acceleration at the top of frame and the bottom of grip during stroke and volley swing were investigated. The correlation between the optimum diameter for grasping of tennis racket and the dimensions of hand was not found. At the ball impact during stroke and volley swing, the acceleration of the bottom of racket grip showed the lower values at the grasping of optimum grip. The pressure produced at fingers had higher values at the tip of thumb and little finger, and at the root of middle and ring fingers. The pressure at fingers showed highest value by the grip having the diameter less than optimum one. It was considered that the optimum diameter for grasping has the merits to reduce the movement of hand at ball impact, and contribute to the accurate swing, on the other hand, at ball impact, the maximum grip force is produced by the diameter less than optimum grasping diameter.

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The purpose of the study is to investigate the Reynolds number dependency of a circular arc airfoil at Reynolds numbers from 1×10³ to 10×10³ by CFD. A block-structured Cartesian-mesh CFD was employed to precisely predict the vortex flowfields in the low Reynolds number region. The calculated aerodynamic coefficients were reasonably matched with wind tunnel tests at different Reynolds numbers. The flow goes along upper surface at lower angles of attack, but separation on the upper surface occurs at the trailing edge as the angle of attack increases when the Reynolds number is 1×10³. On the other hand, 2D vortices are formed on the upper surface at low angles of attack for Reynolds numbers of 5×10³ and 10×10³, and then the laminar separation bubbles (long bubbles) are formed as the angle of attacks increases. This causes the nonlinear increase of lift coefficient.

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Purpose: Toileting independence is important for patients to maintain self-esteem and to return home. Unaffected grip strength and trunk functions have been noted in earlier studies to be associated with toileting independence in stroke patients. The objective of this study was to explore appropriate indices and calculate cut-off values with regard to unaffected grip strength and trunk functions that could be completed in a short time for estimating toileting independence in stroke patients.

Methods: The subjects were 37 stroke patients, each of whom scored at least 21 points in the Revised Hasegawa's Dementia Scale. The patients were divided into independent and non-independent toileting groups by FIM® scores related to toiling items (“Toileting” and “Toilet transfer”). Logistic regression and receiver operating characteristic curve were used to elucidate items that showed an association with the presence or absence of toileting independence, and to calculate cut-off values of grip strength and trunk function from the Stroke Impairment Assessment Set as variables.

Results: Grip strength was significantly associated with toileting independence. The cut-off value was 3 points (sensitivity, 74%; specificity, 71%; receiver operating characteristic area under the curve, 0.730).

Discussion: Because grip strength can be quickly measured, calculated grip strength cut-off values can estimate a patient's ability for toileting independence. However, the cut-off value shown in the present study may be applicable to only patients with good trunk function.

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The low-cycle fatigue behavior of Sn–3.5 mass%Ag, Sn–0.7 mass%Cu lead-free solders and Sn–37 mass%Pb solder were investigated at a strain rate of 0.1%/s with a non-contact extensometer at room temperature (22±3°C). In addition, the relationship between the surface features in the low-cycle fatigue test and the fatigue life of those solders were investigated by image processing. The fatigue lives of Sn–3.5 mass%Ag and Sn–0.7 mass%Cu were better than that of Sn–37 mass%Pb. The low-cycle fatigue behavior on each solder followed Coffin–Manson equation. The surface deformation in fine wrinkles was observed in the low-cycle fatigue test at each solder. The surface features for each solder were evaluated by image processing from the surface deformation. The surface features in the low-cycle fatigue test did not appear until under 10% of the fatigue life for Sn–3.5 mass%Ag, until 10% of the fatigue life for Sn–0.7 mass%Cu, and until 20% of the fatigue life for Sn–37 mass%Pb.

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To achieve precise and stable pipe/thin plate bending based on the penetration bending method,a grip-and-feed mechanism was proposed. This mechanism is driven by an actuator and composed of two cam mechanisms and a chain-drive mechanism. One of the cam mechanisms was designed to generate a periodic grip-and-release motion of grippers, which circulate along a track, by a grooved cam mechanism.The other was designed to constrain the grippers'orientation during feeding to achieve a stable gripping. These mechanisms are synchronously driven by an actuator. Thickness of the rubber attached on the gripper was investigated through experiments. The fundamental performance of the proposed feeder was demonstrated by applying it to fabrication of a circular-shaped pipe. The results are shown to support the proposed mechanism.

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Midazolam (MDZ) is clinically used for its sedative and anticonvulsant properties. However, its prolonged or potentiated effects are sometimes concerning. The main binding protein of MDZ is albumin, and reduced serum albumin levels could lead to MDZ accumulation, thereby potentiating or prolonging its effects. Previous investigations have not thoroughly examined these phenomena from a behavioral pharmacology standpoint. Consequently, this study aimed to evaluate both the prolonged and potentiated effects of MDZ, as well as the effects of serum albumin levels on the action of MDZ in low-albumin rats. Male Wistar rats were classified into control (20% protein diet), low-protein (5% protein), and non-protein groups (0% protein diet) and were fed the protein-controlled diets for 30 d to obtain low-albumin rats. The locomotor activity and muscle relaxant effects of MDZ were evaluated using the rotarod, grip strength, and open-field tests conducted 10, 60, and 120 min after MDZ administration. Serum albumin levels decreased significantly in the low-protein and non-protein diet groups compared with those in the control group. Compared with the control rats, low-albumin rats demonstrated a significantly shorter time to fall, decreased muscle strength, and a significant decrease in the distance traveled after MDZ administration in the rotarod, grip strength, and open-field tests, respectively. Decreased serum albumin levels potentiated and prolonged the effects of MDZ. Hence, serum albumin level is a critical parameter associated with MDZ administration, which should be monitored, and any side effects related to decreased albumin levels should be investigated.

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Background: A 45-year-old Japanese male pharmacist developed a stroke in December 2018; hence, he had left-sided hemiplegia due to the after-effects of cerebral stroke. This paper reports the return-to-work (RTW) and after RTW support for poststroke patients from a combined ergonomic and rehabilitation perspective.

Methods: From April 2019 to July 2020, we visited hospitals and workplaces multiple times, making various preparations for workplace accommodation and exchanging information as follows: allowing staggered working hours; securing the flow routes in the back room; equipping a cane holder on his working desk; and adjusting the position of the work tablet. In August 2020, after RTW, we conducted a brief evaluation of residual motor function and an on-site task analysis, and we subsequently made a support tool.

Results: In July 2020, his RTW was eventually realized. Moreover, as a result of introducing the tailor-made support tool, the duration of certain tasks that he had been claiming to be difficult was reduced when compared to that before support-tool use, and the average task duration before and after support-tool use was 32.8 s and 10 s, respectively (reduced by approximately 69.5%).

Conclusion: To augment our efforts, hospital staff, support staff in his workplace, and his employer collaborated to make various workplace accommodations for the smooth realization of RTW before and after RTW. In the present case, the ergonomic and rehabilitation approach after RTW might have contributed to ease of task, work efficiency, and the potential for future job retention.

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