The excitonic behavior in two-dimensional (2D) heterostructures of transition metal dichalcogenide atomic layers has attracted much attention. Here, we report, for the first time, the ultrafast behavior of charge carriers in heterostructure of metal (NbSe2) and semiconductor (WSe2) atomic layers via ultrafast spectroscopy. We observe a blue-shift of the excited-state absorption peak in time-resolved absorption spectra with time delays in both the as-grown semiconducting WSe2 and the metal–semiconductor heterostructure. However, the heterostructure shows a clear difference in the peak position and relaxation time of its electrons. This result indicates higher excited energy states in WSe2 in the presence of the NbSe2 metallic layer contact and implies the existence of interlayer electron quenching from WSe2 to NbSe2 layers. The heterostructure shows a shorter time scale in the peak rise time compared to bare WSe2, due to interfacial defects between WSe2 and NbSe2 layers. The results offer a better understanding of the optoelectronic properties of 2D heterostructure interfaces.

Two‐dimensional (2D) tungsten diselenide (WSe2)‐based porous three‐dimensional (3D) architecture is fabricated utilizing highly porous 3D alumina structures. The architecture is produced by combining a sol–gel process for fabricating porous 3D alumina and chemical vapor deposition (CVD) for the formation of WSe2. The gas‐sensing performance of the porous 3D structure overcomes the limitations displayed by the gas response of a 2D WSe2‐based gas sensor. This 2D nanomaterials‐based porous 3D architecture is a promising approach for improving the gas response of sensing devices.

Most of the companies have firewalls in order to protect their internal networks and assets from the attacker of the cyber space. Firewall policies should be maintained and organized with high importance. However, considering the length of time needed in analyzing the highly complex policies and the risks of disabling firewall that may arise in case of a false policy setting. It is extremely hard to securely optimize the performance of firewalls. This paper is to suggest a visualization tool that shows the status and the types of policies applied throughout the firewalls so that such difficulties related to the maintenance of firewall policies can be resolved. The proposed tool is designed in six different angles; (1) Hierarchy-view, (2) Anomaly-view, (3) Distributed-view, (4) ANYPolicy-view, (5) SearchResult-view, and (6) Top and Bottom Used-view. The core of the overall function is to facilitate the easy identification of the policy interrelationships. The visualization tool has been tested by being applied across approximately 24 different firewall policies. The processing speed of each function, abuse detection rate were all reviewed positively. By the help of the tool, identifying the services, performance improvement, and visibility of the policy relations, which thereby will lead to better safety in preserving the assets intact. A video of the proposed visualization tool can be found on the web site: https://youtu.be/43OfHN8dteU

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