In the modern industrial period, the introduction of mass production was most important progress in civilization. Die-casting process is one of main methods for mass production in the modern industry. The aluminum die-casting in the mold filling process is very complicated where flow momentum is the high velocity of the liquid metal. Actually, it is almost impossible in complex parts exactly to figure the mold filling performance out with the experimental knowledge. The aluminum die-castings are important processes in the automotive industry to produce the lightweight automobile bodies. Due to this condition, the simulation is going to be more critical role in the design procedure. Simulation can give the best solution of a casting system and also enhance the casting quality. The cost and time savings of the casting layout design are the most advantage of Computer Aided Engineering (CAE).. Generally, the relations of casting conditions such as injection system, gate system, and cooling system should be considered when designing the casting layout. Due to the various relative matters of the above conditions, product defects such as defect extent and location are significantly difference. In this research by using the simulation software (AnyCasting), CAE simulation was conducted with three layout designs to find out the best alternative for the casting layout design of an automotive Oil Pan_BJ3E. In order to apply the simulation results into the production die-casting mold, they were analyzed and compared carefully. Internal porosities which are caused by air entrapments during the filling process were predicted and also the results of three models were compared with the modifications of the gate system and overflows. Internal porosities which are occurred during the solidification process are predicted with the solidification analysis. And also the results of the modified gate system are compared.

In crystalline solar cells, the substrate itself constitutes a large portion of the fabrication cost as it is derived fromsemiconductor ingots grown in costly high temperature processes. Thinner wafer substrates allow some cost saving as morewafers can be sliced from a given ingot, although technological limitations in slicing or sawing of wafers off an ingot, as wellas the physical strength of the sliced wafers, put a lower limit on the substrate thickness. Complementary to these economicaland techno-physical points of view, a device operation point of view of the substrate thickness would be useful. With this inmind, BC-BJ Si and GaAs solar cells are compared one to one by means of the Medici device simulation, with a particularemphasis on the substrate thickness. Under ideal conditions of 0.6µm photons entering the 10µm-wide BC-BJ solar cells atthe normal incident angle (θ=90o), GaAs is about 2.3 times more efficient than Si in terms of peak cell power output:42.3mW·cm−2 vs. 18.2mW·cm−2. This strong performance of GaAs, though only under ideal conditions, gives a strongindication that this material could stand competitively against Si, despite its known high material and process costs. Within thelimitation of the minority carrier recombination lifetime value of 5×10−5 sec used in the device simulation, the solar cell poweris known to be only weakly dependent on the substrate thickness, particularly under about 100µm, for both Si and GaAs.Though the optimum substrate thickness is about 100µm or less, the reduction in the power output is less than 10% from thepeak values even when the substrate thickness is increased to 190µm. Thus, for crystalline Si and GaAs with a relatively longrecombination lifetime, extra efforts to be spent on thinning the substrate should be weighed against the expected actual gainin the solar cell output power.

코로나 바이러스의 영향으로 2020년에 중국은 장시간 동안 '자택 격리' 상태에 있었고 매장이 문을 닫고 식당과 오락장소가 영업을 중단했다. 쇼핑센터, 극장, 관광, 음식 등 오프라인 소비에 큰 충격을 주 었다. 조사연구에 따르면 코로나바이러스가 발생한 후 85%의 식음료업계는 고객수량이 동기 대비 80% 이상 떨어졌고 그 중에서 60%가 영업을 중단했다고 밝혔다. 이 갑작스러운 코로나 바이러스로 인해 전 국민의 생산이나 생활방식이 신속하게 바뀌었고 전통적인 매장의 판매 모델은 곤경에 빠졌다. 전통적인 소매업계는 어려움을 겪으면서 영업 수입이 급감하는 심각한 도전에 직면했을 뿐만 아니라 임금복지, 영업세, 임대료 등 고정비용 부담까지 겹쳐 있다. 그러나 시장 경제가 정체된 것처럼 보이는 상황에서 신흥 판매 모델은 점점 인기를 끌고 시장과 각 분야의 인정을 받고 있다. '밖에 나가지 않는 상태는 사람들의 소비 행위를 완전히 제한하지 않는 것 같다. 5G 인터넷 기술에 의해 빠르고 효율적이며 거의 미친 듯 한 온라인 생방송 판매 모델은 오프라인 매장과 온라인에서 병행하는 새로운 판매 모델을 신속 하게 추진했다. 그렇기 때문에 소매상들은 구조 전환의 속도를 빠르게 하고 위기에서 생존을 추구하며 뜨거운 '온라인 생방송' 모델은 판매를 추진하고 소비를 추진하는 큰 기대를 가진다. 이런 상황에서 많 은 업체들도 '캐스터' 로 변신하여 판로를 확대한다. 코로나 바이러스심각하기 때문에 중국 소매업도 빠르게 온라인 생방송 마케팅 시대에 접어들었다.