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Thermoelectric convection in a plane capacitor is investigated in a microgravity environment and in the case of the thermal stable and unstable stratification in terrestrial conditions. Energetic analysis shows that in the thermal stable stratification, the thermoelectric convection is delayed while in the thermal unstable stratification, it is enhanced by the Archimedean buoyancy before the latter takes over the dielectrophoretic buoyancy and drives natural thermal convection. An experiment in parabolic flights shows the formation of thermoelectric convection at the end of the microgravity phase.

It is widely accepted that rational individuals are unable to create cooperation in a prisoner’s dilemma. However, in everyday life, cooperation, for example, during a fishing moratorium, can be observed frequently. Additionally, the appearance of cooperation in the prisoner’s dilemma can be seen in numerous simulation studies. This paper reviews 31 simulation studies published between January 2017 and January 2023 in which agents can be observed in the results to improve cooperation in a prisoner’s dilemma. The proposed methodologies were sorted into seven categories, including Bounded Rationality, Memory, Adaptive Strategy, Mood Model, Intrinsic Reward, Network Dynamics, and Altruistic Attribute. Based on their impacts, the effectiveness of these seven approaches was classified into three categories: generating cooperation, maintaining cooperation, and spreading cooperation. This review is expected to be helpful for scholars conducting future research on multi-agent cooperation and irrational agent modeling.

Tensile stress is internally induced when soil shrinkage due to desiccation is restricted, and cracks occur when the induced tensile stress reaches tensile strength. Various numerical models have been proposed to predict crack initiation; however, the validity of the computed internal stresses during the cracking process has not been assessed, although the internal stresses directly influence the crack initiation. The aim of this study was to demonstrate the effectiveness of a laboratory-based desiccation stress test, which measures the induced tensile stress until crack initiation. Desiccation stress tests were performed on unsaturated sandy soil with two different water contents. The measured tensile stress until cracking was numerically simulated using a hypo-elastic model based on the skeleton stress considering the suction effects. The computed tensile stress was consistent with the measured values throughout the cracking process in both cases, with different initial water contents. Stress-based validation using the results of the desiccation stress test demonstrated that the proposed constitutive model yields reliable estimations of the internal tensile stress in unsaturated soils until crack initiation.

In this study, the hardened properties and spraying characteristics of ultra high strength fiber-reinforced mortar mixed with copper fibers along with nylon fibers and polypropylene fibers are examined. The chemical fibers are added in the expectation that they will prevent cracking during initial curing. It is confirmed that, even with the addition of chemical fibers, the fresh properties of the mortar are similar to those of formulations containing only copper fibers. It is also found spray-application of this formulation achieves sufficient application thickness and that on-site application would be possible.

Egypt is host to an estimated 150,000 Iraqi refugees. Initiallyarriving with high hopes of resettlement, their resources arenow depleted, they are unable to work, their children are outof school and their community is fractured by divisions

The analysis of 20-year long-term semidiurnal lunar tidal variations gave the evidence that the semidiurnal variations are completely different between the magnetic quiet and disturbed periods. This is the first time that the seasonal dependence of disturbance-time semidiurnal variation has been provided from the analysis of the EE-index. We found the Kp dependence of semidiurnal variation: For full and new moon phase, counter troughs are amplified during disturbance time, possibly related to disturbance dynamo. For all moon phase, there are positive enhancements in dawn and strong depressions after sunset, resulting from the penetration of polar electric filed. For Seasonal dependence, semidiurnal variations are divided to three seasonal groups, and characterized as deep trough, enhanced crest and weak structure for D-solstice, Equinoxes and J-solstice, respectively. There is no significant longitudinal difference between Ancon and Davao, except for the amplitude of semidiurnal variations. The deep troughs occur during D-solstice and the enhanced crests during Equinoxes, at both Ancon and Davao.

Application of acid in HTC process has been confirmed to have effect on hydrochar properties related to its adsorption capacity. Woody materials (tree branches) were used to investigate the relation of nitric acid addition in HTC process on the hydrochar surface properties and its adsorption mechanism toward cadmium in water solution. Tree branches were processed at 200-260 °C mixed with water and nitric acid (HNO3) at ratio 0-50% to hydrochar mass and held for holding time of 30, 105 and 180 minutes. Batch adsorption test was conducted by mixing the hydrochars with cadmium solution at 100 ppm and shaken for 24 hours at room temperature. The BET surface area, oxygen functional group (OFG) and the exchanged cations were analysed to investigate the effect of HTC process condition, nitric acid addition, and adsorption mechanism of cadmium. Tree branches treated at 200°C for 30 minutes and acid ratio of 50% showed the best adsorption result. Analysis on the surface properties also showed the best condition for cadmium adsorption. Thus hydrothermal treatment condition at low temperature, short time and high acid ratio usage could be effective in removing cadmium from water. The cadmium adsorption by cation exchange interaction might be the major adsorption mechanism as shown by consistency of trend of the exchanged cation concentration with cadmium adsorption capacit

Intense X-ray fluxes during solar flares are known to cause enhanced ionization in the Earth’s ionospheric D, E and F region. This sudden change of ionospheric electron density profile is serious problem to radio wave communication and navigation system. The ground magnetograms often record the sudden change in the sunlit hemisphere during the enhanced X-ray flux, due to the sudden increase in the global ionospheric current system caused by the flare-induced enhanced ionospheric conductivity. These geomagnetic field disturbances are known as ‘‘solar flare effects’’ (SFEs) or geomagnetic crochets [Campbell, 2003]. The typical SFE is increase variation on the equatorial magnetic data. On Ionosonde observation during solar flare event, the High-Frequency (HF) radio wave blackout is often detected in ionogram due to the sudden disturbance in ionosphere. Two intense X-class solar flares occurred on 6 and 10 September 2017. We investigated the magnetic field and Ionosonde responses to the intense solar flare events. Dayside magnetic field variations sudden increased due to the ionospheric disturbance resulting from solar flare. There is no response in night side magnetometer data. The magnitude of SFE (magnetic field) is independent of solar flare x-ray magnitude. We found HF radio wave blackout in ionogram at dayside Ionosonde stations. The duration of blackout is dependent of latitude and local time of Ionosonde stations. There is the different feature of ionogram at night side.

We examined the Schumann resonance (SR) at low-latitude station KUJ by comparing with solar X-ray flux and solar proton flux at a geostationary orbit. For intense solar activity in October-November 2003, the reaction of the SR frequency to X-ray enhancement and SPEs was different. The SR frequency in H component increased at the time of the Xray enhancement. The response of SR seems to be caused by the increase of the electron density in the ionospheric D region which ionized by the enhanced solar X-ray flux. In the case of the SPEs, the SR frequency in D component decreased with enhancement of solar proton flux. We suggest that the SPEs caused the decrease of altitude on the ionopheric D region at high-latitude region, and the SR frequency decreased.

No Brasil, em decorrência da implantação do Sistema Único de Saúde, houve nos últimos anos o crescimento da oferta de serviços na atenção primária, indicando a ampliação de acesso a esses serviços. Um dos desafios no atendimento às necessidades de saúde da população tem sido a avaliação e o monitoramento destes serviços. A lista brasileira de internações por condições sensíveis à atenção primária é um dos instrumentos para esta avaliação. O objetivo deste estudo foi compreender como os profissionais de saúde percebem a internação de usuários sob seu acompanhamento, com diagnósticos que fazem parte desta lista. É um estudo descritivo e exploratório, do tipo qualitativo, performado na cidade de São Paulo, no qual fizeram parte profissionais da Estratégia de Saúde da Família, que forneceram os dados através de entrevista. Particularmente neste estudo intentou-se destacar a potencialidade de uma ferramenta decodificadora aplicada aos discursos dos pesquisandos. A ferramenta mostrou-se potente para a realização deste estudo, na medida em que ressaltou, no material coletado, as estruturas mais significativas, objetivando na análise aquilo que é subjetivo da percepção dos profissionais. O estudo apontou que na percepção de profissionais essas internações ocorrem em decorrência de vários fatores, entre eles: pouca escolarização dos usuários; dificuldade de eles entenderem as recomendações e aderirem ao tratamento; ter hábitos alimentares pouco saudáveis; dificuldades decorrentes de fatores ambientais e socioeconômicos. Admitem que a atenção primária sozinha não é suficiente para enfrentar os problemas de saúde. O estudo mostra que as práticas assistenciais são fundadas nas teorias multicausais que ficam limitadas diante dos determinantes sociais da saúde e da doença. Interpretadas dessa maneira, as intervenções encontram-se reduzidas, de forma pontual, segmentada e sem articulação com a totalidade maior a que o fenômeno está inscrito.

Our method for synthesizing the mesoporous silica hollow capsules (MSHCs) was combined with the Layer-by-Layer method to integrate the magnetic nanoparticles (mNPs) onto the core template for the MSHC synthesis. The resultant magnetic MSHCs (mMSHCs) were monodisperse as the conventional MSHCs, and the mNPs were embedded on the inner surface of the mesoporous silica shell. The same mesoporous structure as in the MSHCs was confirmed in the mMSHCs and the properties of the mNPs were maintained even after being incorporated into the mMSHCs.

For study of coupling processes in the Solar-Terrestrial System, International Center for Space Weather Science and Education (ICSWSE), Kyushu University has developed a real time magnetic data acquisition system (the MAGDAS project) around the world. The number of observational sites is increasing every year with the collaboration of host countries. Now at this time, the MAGDAS Project has installed 78 real time magnetometers – so it is the largest magnetometer array in the world. The history of global observation at Kyushu University is over 30 years and number of developed observational sites is over 140. Especially, Collaboration between IKIR is extended back to 1990's. Now a time, we are operating Flux-gate magnetometer and FM-CW Radar. It is one of most important collaboration for space weather monitoring. By using MAGDAS data, ICSWSE produces many types of space weather index, such as EE-index (for monitoring long tern and shot term variation of equatorial electrojet), Pc5 index (for monitoring solar-wind velocity and high energy electron flux), Sq-index (for monitoring global change of ionospheric low and middle latitudinal current system), and Pc3 index (for monitoring of plasma density variation at low latitudes). In this report, we will introduce recent development of MAGDAS/ICSWSE Indexes project and topics for new open policy for MAGDAS data will be also discussed.

The ground magnetic field variation in the extremely low frequency (ELF) range has been measured by an induction magnetometer at Kuju, Japan (KUJ; M.Lat. = 23.4 degrees, M. Lon. = 201.0 degrees) since 2003. The first mode of the Schumann resonance (SR) around 8 Hz can be seen at KUJ. The SR in H (horizontal northward component) shows maximum peaks around 08 UT and 15 UT. In the case of D (horizontal eastward component), the SR shows its maximum peak around 08 UT. These peaks are coincident with the enhancement of lightning activity in Africa and Asia. Thus, we found the influence of the lightning activity on the observed SR at KUJ.