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On 2020 December 5 at 17:28 UTC, Japan Aerospace Exploration Agency's Hayabusa2 sample return capsule (SRC) re-entered Earth's atmosphere. The capsule passed through the atmosphere at supersonic speeds, emitting sound and light. The inaudible sound was recorded by infrasound sensors installed by Kochi University of Technology and Curtin University. Based on analysis of the recorded infrasound, the trajectory of the SRC in two cases, one with constant-velocity linear motion and the other with silent flight, could be estimated with an accuracy of 0° 5 in elevation and 1° in direction. A comparison with optical observations suggests a state of flight in which no light is emitted but sound is emitted. In this paper, we describe the method and results of the trajectory estimation.

On 5th December 2020 at 17:28 UTC, the Japan Aerospace Exploration Agency's Hayabusa-2 sample return capsule came back to the Earth. It re-entered the atmosphere over South Australia, visible for 53 seconds as a fireball from near the Northern Territory border toward Woomera where it landed in the the Woomera military test range. A scientific observation campaign was planned to observe the optical, seismo-acoustic, radio and high energy particle phenomena associated with the entry of an interplanetary object. A multi-institutional collaboration between Australian and Japanese universities resulted in the deployment of 49 instruments, with a further 13 permanent observation sites. The campaign successfully recorded optical, seismo-acoustic and spectral data for this event which will allow an in depth analysis of the effects produced by interplanetary objects impacting the Earth's atmosphere. This will allow future comparison and insights to be made with natural meteoroid objects., Comment: accepted in Publications of the Astronomical Society of Japan

On 5th December 2020 at 17:28 UTC, the Japan Aerospace Exploration Agency's Hayabusa-2 sample return capsule came back to the Earth. It re-entered the atmosphere over South Australia, visible for 53 seconds as a fireball from near the Northern Territory border toward Woomera where it landed in the the Woomera military test range. A scientific observation campaign was planned to observe the optical, seismo-acoustic, radio and high energy particle phenomena associated with the entry of an interplanetary object. A multi-institutional collaboration between Australian and Japanese universities resulted in the deployment of 49 instruments, with a further 13 permanent observation sites. The campaign successfully recorded optical, seismo-acoustic and spectral data for this event which will allow an in depth analysis of the effects produced by interplanetary objects impacting the Earth's atmosphere. This will allow future comparison and insights to be made with natural meteoroid objects., Comment: accepted in Publications of the Astronomical Society of Japan

type:Journal Article, In this paper, magnetic levitation tool with superconducting bulks is introduced as a new hollow machining technology. Magnetic levitation tool is the machine that magnet levitates above superconducting bulks and driving force of rotating magnet shaves the object. This tool is expected to use for a grinding machine and machining device because of hollow machining and micromachining by strong fixing. For using magnetic levitation tool, the attractive force, the repulsive force and rotating torque are important for grinding machine, machining outer surface and both, respectively. These forces are calculated by FEM, and compared with experimental results. The experimental results are agreed well with calculated results. However, the attractive force is one order smaller than that required in chemical mechanical polishing., source:doi :10.1088/1742-6596/871/1/012048

type:Journal Article, The trapped magnetic field properties of superconducting MgB2 bulk magnets with various shapes such as a triangular, a quadrangular, a hexangular bulk were calculated by the Finite Elements Method (FEM). The effect for the combination of several numbers of bulks was also investigated for several kinds of shapes to obtain large area of bulk surface in spite of one large bulk. In this calculation, the simple magnetization process replaced by the field-cool magnetization was used to obtain the equivalent distribution of the magnetic field, and the thermal equation in FEM was omitted. The trapped magnetic field for the triangular bulk by FEM was compared with the experimental result. It was found that the calculated results agreed well with the experimental result. The maximum trapped magnetic field was obtained in the cylindrical shape among several kinds of shapes. The trapped magnetic field was increased by the combination of multi-bulks. It was confirmed that the trapped magnetic field of the multi-bulks was larger than that of the single bulk. The trapped magnetic field increases with increasing the number of the bulks., 28th International Symposium on Superconductivity(ISS 2015), November 16-18, 2015, Tokyo, Japan, source:https://doi.org/10.1016/j.phpro.2016.04.027

A design scheme is proposed to evaluate the safety of continuous linear structure i.e. river levee. The scheme is developed to establish a procedure to continuously evaluate the stability failure of embankment during flood runoff by seepage, and to identify locations for reinforcement of river levee. A 20km stretch of a fairly large river running through one of the major cities in Japan is chosen for a case study. First all the information available for this river levee for the both side of river have been collected and complied. The data include river levee configurations for every 200m, all the soil investigation results done in the past and the results of levee safety inspection by MLIT. The strength parameters of the embankment and the foundation are obtained from about 50 triaxial test results (CUbar). The permeability coefficient is estimated from about 300 grain size distribution and 15 permeability test results. The configurations of the levee sections are analyzed, and the ranges of various dimensions, such as slope inclinations, crown width, height of retaining wall at edge of slope etc., are obtained. Based on these information, detailed seepage and stability analyses for the possible dimensions of levee sections and material properties are carried out to get the response function (RS) for the safety assessment. Based on this information, the response surface (RS) for the river levee is developed. In developing RS, the experimental design technique is applied for efficiency. MCS is applied to evaluate the failure probability of the levee based on the parameters obtained from the all the analyses explained above for every 200m interval along the levee because all the configuration dimensions of the levee is available at these sections. Results of MCS are presented along the levee, which immediately shows less safe sections.

A design scheme is proposed to evaluate the safety of continuous linear structure i.e. river levee. The scheme is developed to establish a procedure to continuously evaluate the stability failure of embankment during flood runoff by seepage, and to identify locations for reinforcement of river levee. A 20km stretch of a fairly large river running through one of the major cities in Japan is chosen for a case study. First all the information available for this river levee for the both side of river have been collected and complied. The data include river levee configurations for every 200m, all the soil investigation results done in the past and the results of levee safety inspection by MLIT. The strength parameters of the embankment and the foundation are obtained from about 50 triaxial test results (CUbar). The permeability coefficient is estimated from about 300 grain size distribution and 15 permeability test results. The configurations of the levee sections are analyzed, and the ranges of various dimensions, such as slope inclinations, crown width, height of retaining wall at edge of slope etc., are obtained. Based on these information, detailed seepage and stability analyses for the possible dimensions of levee sections and material properties are carried out to get the response function (RS) for the safety assessment. Based on this information, the response surface (RS) for the river levee is developed. In developing RS, the experimental design technique is applied for efficiency. MCS is applied to evaluate the failure probability of the levee based on the parameters obtained from the all the analyses explained above for every 200m interval along the levee because all the configuration dimensions of the levee is available at these sections. Results of MCS are presented along the levee, which immediately shows less safe sections.

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The incidence of systemic Candida infections in patients requiring intensive care has increased substantially in recent years as a result of a combination of factors. More patients with severe underlying disease or immunosuppression from anti-neoplastic or anti-rejection chemotherapy and at risk from fungal infection are now admitted to the ICU. Improvements in supportive medical and surgical care have led to many patients who would previously have died as a result of trauma or disease surviving to receive intensive care. Moreover, some therapeutic interventions used in the ICU, most notably broad-spectrum antibiotics and intravascular catheters, are also associated with increased risks of candidiasis. Systemic Candida infections are associated with a high morbidity and mortality, but remain difficult to diagnose and ICU staff need to be acutely aware of this often insidious pathogen. A number of studies have identified risk factors for systemic Candida infection which may be used to identify those at highest risk. Such patients may be potential candidates for early, presumptive therapy. Here we review the epidemiology, pathogenesis, morbidity and mortality of systemic Candida infections in the ICU setting, and examine predisposing risk factors. Antifungal treatment, including the use of amphotericin B, flucytosine and fluconazole, and the roles of early presumptive therapy and prophylaxis, is also reviewed.

A number of horizontal pillars are left in the mine to protect main haulage drifts. Recovery of these pillars is a major problem in the mine, and recently much effort has been made to recover the pillars by a mechanised cut and fill method. A case history is presented of the recovery of a large horizontal pillar 3000 m2 in area and 28 m thick. The pillar was divided into two parts and the hanging wall block mined upwards until the thickness of the pillar reached a critical value. The mined space was then filled with sand-slime. After completion of the filling, the residual ore on the foot wall side was recovered., A number of horizontal pillars are left in the mine to protect main haulage drifts. Recovery of these pillars is a major problem in the mine, and recently much effort has been made to recover the pillars by a mechanised cut and fill method. A case history is presented of the recovery of a large horizontal pillar 3000 m2 in area and 28 m thick. The pillar was divided into two parts and the hanging wall block mined upwards until the thickness of the pillar reached a critical value. The mined space was then filled with sand-slime. After completion of the filling, the residual ore on the foot wall side was recovered.

Lead and zinc ores are mined at Toyoha, Japan, with rock temperatures reaching 80 to 90 degrees C. Measurements were taken to investigate the heat balance in the drift. Results show that the heat transfer from rock affected by hot mineral water to the air is not as great as expected, but a large heat transfer occurs if the air contacts hot water which has seeped into the drift. For effective cooling it is advisable to prevent seepage of hot mineral water, to prevent the air current from contacting the hot water, and to use chilled water efficiently., Lead and zinc ores are mined at Toyoha, Japan, with rock temperatures reaching 80 to 90 degrees C. Measurements were taken to investigate the heat balance in the drift. Results show that the heat transfer from rock affected by hot mineral water to the air is not as great as expected, but a large heat transfer occurs if the air contacts hot water which has seeped into the drift. For effective cooling it is advisable to prevent seepage of hot mineral water, to prevent the air current from contacting the hot water, and to use chilled water efficiently.

Methods of predicting temperatures and humidities of air currents in tunnels and mines have been studied, and a new method has been developed to improve the accuracy of the calculation. The temperature and humidity were found to be influenced by a drop in wall temperature of the wet part of the airway. A good correlation was found between calculated and measured values of the temperature and humidity., Methods of predicting temperatures and humidities of air currents in tunnels and mines have been studied, and a new method has been developed to improve the accuracy of the calculation. The temperature and humidity were found to be influenced by a drop in wall temperature of the wet part of the airway. A good correlation was found between calculated and measured values of the temperature and humidity.

Measurements of deformation and variation in rock stress were carried out to investigate safe mining with high extraction and no surface damage. It was found that stress could be monitored by a photoelastic stressmeter in the early stages of mining. Some rock failure occurred in these early stages. Rock failure rarely occurred after secondary mining had progressed, but large and complicated deformations were recorded. By the stress relief technique, it was found that the original stress in the east/west direction was about three times the vertical one., Measurements of deformation and variation in rock stress were carried out to investigate safe mining with high extraction and no surface damage. It was found that stress could be monitored by a photoelastic stressmeter in the early stages of mining. Some rock failure occurred in these early stages. Rock failure rarely occurred after secondary mining had progressed, but large and complicated deformations were recorded. By the stress relief technique, it was found that the original stress in the east/west direction was about three times the vertical one.

The massive, large pyrite body is mined by leaving rib pillars. Secondary mining by pillar recovery has been attempted without causing surface subsidence or fracturing. A programme of field measurements: deformation of roof rock, tilt of the floor of a mine level, rock stress states, subsidence of the roof rock, and average horizontal strain in a pillar, was carried out to monitor the stability of the pillars and ground. By the end of 1978 about 67% of the mineable ore had been successfully mined., The massive, large pyrite body is mined by leaving rib pillars. Secondary mining by pillar recovery has been attempted without causing surface subsidence or fracturing. A programme of field measurements: deformation of roof rock, tilt of the floor of a mine level, rock stress states, subsidence of the roof rock, and average horizontal strain in a pillar, was carried out to monitor the stability of the pillars and ground. By the end of 1978 about 67% of the mineable ore had been successfully mined.