Heat removal has become an increasingly crucial issue for microelectronic chips due to increasingly high speed and high performance. One solution is to increase the thermal conductivity of the corresponding dielectrics. However, traditional approach to adding solid heat conductive nanoparticles to polymer dielectrics led to a significant weight increase. Here we propose a dielectric polymer filled with heat conductive hollow nanoparticles to mitigate the weight gain. Our mesoscale simulation of heat conduction through this dielectric polymer composite microstructure using the phase-field spectral iterative perturbation method demonstrates the simultaneous achievement of enhanced effective thermal conductivity and the low density. It is shown that additional heat conductivity enhancement can be achieved by wrapping the hollow nanoparticles with graphene layers. The underlying mesoscale mechanism of such a microstructure design and the quantitative effect of interfacial thermal resistance will be discussed. This work is expected to stimulate future efforts to develop light-weight thermal conductive polymer nanocomposites.

The mining issue’s real-world impact is directly linked to the insufficient policing efforts by relevant institutions, potentially affecting the credibility of law enforcement agencies and regional performance. This research project sought to evaluate policing performance related to mining activities in Indonesian regional areas. Using an indexing method, a composite index was developed based on supervision, partnership, and law enforcement aspects. This index functioned as a representation of policing within the mining and quarrying context. The evaluation was carried out in Indonesian provinces with active mining and quarrying operations. The composite index was then juxtaposed with regional gross domestic products to gauge the correlation between policing and regional economic performance. Results revealed that regions heavily reliant on mining for regional GDP, like East Kalimantan, South Sumatera, and Papua, tended to have lower policing indices due to shortcomings in supervision and law enforcement. Conversely, regions with stronger policing indices typically excelled in the supervisory dimension, as seen in Yogyakarta. The study suggests that engaging with communities and increasing the ratio of mine inspectors to mine areas can enhance mining governance and regional competitiveness. Boosting the number of mine inspectors in specific areas can also positively impact overall policing activities within mining regions.