Effective processing and use of coal slime is of great significance to protect the environment and save resources. Different coal slimes (untreated with 43 wt% ash content, crushed and flotation treated with 10 wt% ash content, and pre-carbonized) were activated with KOH to prepare porous activated carbon. The results show the activated carbon prepared from coal slime with 10 wt% ash had high specific surface area (3037 m2/ g) and pore volume (1.66 cm3/ g), which was ascribed to the suitable contents of minerals as template and oxygen-containing functional groups. Electrochemical measurements exhibited the best specific capacitance of 220 F/g at 0.1 A/g and the cycle stability of over 100% capacitance retention after 1000 cycles at 5 A/g in 6 M KOH solution. Due to the high specific surface area, superior electrochemical performance, and facile and low cost, developing highly porous activated carbon for supercapacitors is one alternative way for effective use of coal slime waste.

To investigate the effect of gas dispersing carbon nanotubes (CNTs) and hot pressing method on the transparency and the conductivity of thin films, the free arc was used to disperse the CNTs in a high dispersion rate, and the dispersed CNTs were rapidly pressed into the surface of the PET film by hot pressing to obtain electrical conductivity. The relationship between the light transmission and sheet resistance of the film was studied by changing the deposition time and the presence or absence of electrostatic adsorption. It was found that the CNTs modified film still retains good electrical conductivity (sheet resistance up to 6 × 104 Ω, light transmittance 69%) through the cleaning of surfactants and ultrasonic waves, which proves that hot pressing is a simple physical method to achieve effective combination of CNTs and films.

Heteroatoms in situ-doped hierarchical porous hollow-activated carbons (HPHACs) have been prepared innovatively by pyrolyzation of setaria viridis combined with alkaline activation for the first time. The micro-morphology, pore structure, chemical compositions, and electrochemical properties are researched in detail. The obtained HPHACs are served as outstanding electrode materials in electrochemical energy storage ascribe to the particular hierarchical porous and hollow structure, and the precursor setaria viridis is advantage of eco-friendly as well as cost-effective. Electrochemical measurement results of the HPHACs electrodes exhibit not only high specific capacitance of 350 F g−1 at 0.2 A g−1, and impressive surface specific capacitance (Cs) of 49.9 μF cm−2, but also substantial rate capability of 68% retention (238 F g−1 at 10 A g−1) and good cycle stability with 99% retention over 5000 cycles at 5 A g−1 in 6 M KOH. Besides, the symmetrical supercapacitor device based on the HPHACs electrodes exhibits excellent energy density of 49.5 Wh kg−1 at power density of 175 W kg−1, but still maintains favorable energy density of 32.0 Wh kg−1 at current density of 1 A g−1 in 1-ethy-3-methylimidazolium tetrafluoroborate ( EMIMBF4) ionic liquid electrolyte, and the excellent cycle stability behaviour shows the nearly 97% ratio capacitance retention of the initial capacitance after 10,000 cycles at current density of 2 A g−1. Overall, the results indicate that HPHACs derived from setaria viridis have appealing electrochemical performances thus are promising electrode materials for supercapacitor devices and large-scale applications.

최근 한국에서는 고속도로 제한속도 증가 정책에 따라 도로기하구조의 변화와 관련된 고속도로 안전문 제가 이슈화 되어 왔다. 이러한 도로선형 변화에 따른 고속도로 안전문제의 올바른 해결을 위하여 본 연 구는 고속도로의 다양한 기하구조, 특히, 평면커브와 종단커브가 오버랩 된 고속도로구간을 대상으로 도 로기하구조 패턴을 그룹화하여 각각의 그룹에 맞는 안전대책을 세분화 하는데 목적을 두고 있다. 이러한 목적을 달성하기 위해 본 연구에서는 여러 클러스터링 테크닉들을 국내 고속도로의 기하구조데 이터에 적용하여 최적의 클러스터링 방법론을 찾고 각각의 기하구조 클러스터에서 발생한 사고데이터들 을 기반으로 클러스터 기반 사고심각도 예측 모델링을 실시하였다. 그 결과, K-means 클러스터링 기법 이 최적의 클러스터링 기법으로 확인되었으며 평면 및 종단커브 선형은 6개의 패턴으로 그룹화 되었다. 또한 각 6개의 클러스터로 그룹화 된 구간에서의 사고 심각도를 예측한 결과 어리거나 나이든 운전자, 야 간, 미숙한 바퀴조작, 사고 처리시간이 사망 및 부상이 포함된 심각한 사고를 증가시키는 요인으로 나타 났다. 위 결과를 통하여 본 연구는 고속도로의 평면 및 종단커브 조합구간에서 선형요소들의 특성별로 그 패 턴을 그룹화하여 사고 심각도를 낮추기 위한 고속도로 안전대책을 세분화하여 제안하였다. 본 연구에서 쓰인 방법론과 세분화되어 제시된 안전대책은 제한속도 증가에 따른 고속도로에서 안전향상을 위해 연구 자. 도로안전정책 입안자 및 현장 기술자들에게 실질적으로 유용하게 쓰일 수 있을 것이다.