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Affordable apartments in tropical developing countries generally have double-loaded corridors to maximise the total floor areas. Building designs with double-loaded corridors often suffer from poor environmental conditions. Passive design using a vertical void can help improve the natural ventilation in the such building design. This study investigates the effectiveness of vertical voids in enhancing the wind speed in the building. An experimental building with a vertical void, open pilotis, penthouse at rooftop and wind fin on the ground floor to help direct air to the void was constructed in Tegal, Indonesia. Five cases were considered by controlling the window openings, louver openings on the roof and change in fin size at pilotis. Wind speed and direction were recorded at one-second intervals. High wind speed was experienced in the pilotis and void when the wind direction is from the north and the wind speed in the void improved due to the wind fin being placed on the south corridor of the building. The results show the average wind speed in the void is twice as high as compared to the corridors. The building design performed best with high wind speeds in the void and corridores when all windows were kept open.

Pellagra is a nutritional disorder of niacin deficiency which is characterized by triad of dermatitis, diarrhea and dementia. It is often seen in a state of poor nutrition among alcoholics, homeless and patients suffering from malabsorption. Though seldom occurs in children, its re-emerging is seen as a result of worsening food security in vulnerable population during conflict or insurgency. We report the case of 12-year-old female pastoralist who presented darkening and thickening of the hands, feet, ankles, neck and her upper trunk. Conflicts and insurgency usually occur in resource constraint settings where health workers are few and overworked. Therefore, continuously educating health workers and the general public regarding nutrition and its disorders like pellagra is a priority. Public Health authorities and policy makers also ought to take pediatric nutrition serious in order to avoid its escalation in internally displaced persons or children orphaned by insurgency.

Extraction by slug flow gives high mass transfer rate and rapid phase separation than the conventional extraction operation. Therefore, there are many advantages such as the volume of the device becomes small and the solvent drastically reduced. The slug flow extraction is expected as a sophisticated separation process. Especially, these advantages become more prominent in the multistage extraction. In this study, the extraction by the slug flow was applied to mutual separation of lithium, cobalt and nickel ions in the mixed aqueous solution. We succeeded in developing a process with lithium, cobalt, nickel ion purity of 85% or more and recovery rate of 90-95%. Furthermore, it was also confirmed that the flow state of the liquid is influenced by the hydrophobicity (PTFE) and hydrophilicity (glass) of the extraction tube. The overall mass transfer volumetric coefficient is affected by (1) the interface area of the oil phase and aqueous phase, (2) the strength of the circulating flow in each segment of the liquid, and (3) the volume flow ratio of the oil phase and the aqueous phase.

Microstructural features and short crack growth behavior were characterized and linked in a Ti-6Al-4V by employing X-ray micro-tomography combined with EBSD serial sectioning. Statistical analysis was used to rank the contributing features to the crack behavior. Afterwards, by creating surrogate models, the microstructural mechanism controlling the short crack behavior were revealed. Short crack preferably grows inside the predominant α phase above the average microstructural fraction. A high number of grains in contact with cracked α grains elongated in the loading direction may impose a constraint on the crack opening resulting in low crack growth rates. As the crack front becomes larger, the increase in the shear stress field away from the cracked grain leads to crack bifurcations, resulting in a decrease in crack driving forces with low crack growth rates. This leads to a preferable growth in α+β phase and along the interface above the average microstructural fractions.

Synchrotron X-ray microtomography was utilized to observe the complex 3D crack morphology and the closure behavior of a short crack in Ti-6Al-4V alloy. The aim of the study was to investigate the effect of the crack path evolution on the 3D short crack closure behavior. In situ fatigue tests at R = 0.1 were carried out using microtomography with a spatial resolution of 1 μm. The 3D crack morphology was observed in detail consisting of non-facets (zigzag), branching, and facets with deflection angles indicating the presence of mode II and mode III displacements. The crack grows with facet-like paths mainly in α grains as compared to the non-facet paths in the α+β grains. The change in the crack path from facet-like paths to non-facet-like paths in the larger crack front induces an increase in the fractional area of closed patches.

This article summarizes applications of sol-gel coatings to modify surface properties, and the process is illustrated with several examples. The use of azobenzene-modified silanes leads to a photoswitchable coating displaying light-controlled wettability. Silane coupling reactions are used to coat surfaces with polymers, in order to hinder the ice crystal growth on surfaces. Liquid-like coatings based on poly(ethylene glycol) show anti-adhesive properties to lime. The preparation of aerogels could be improved by selecting proper silanes as coupling agents to the inner surface of the pores. These examples illustrate that sol-gel processes based on silianation reactons are most promising for industrial applications.

Recently, various types of sensors have been developed. Using these sensors, IoT systems have become hot topics in embedded system domain. However, sensor selections for embedded systems are not well discussed up to now. This paper focuses on embedded system’s features and architecture, and proposes a sensor selection method which is composed seven steps. In addition, we applied the proposed method to a simple example – a sensor selection for computer scored answer sheet reader unit. From this case study, an idea to use FTA in sensor selection is also discussed.

The properties of solids and liquids are strongly influenced by surface phenomena. At the interface of two phases, properties like wetting, adhesion and friction are determined by the degree of interaction between the phases. Controlling this interaction by means of chemistry at interfaces represents the major research topic of the Laboratory of Industrial Chemistry at ZHW.