This study adopted the LS-DYNA mapping algorithm to implement a numerical simulation of a near-surface burst and steel plate non-contact explosion experiments. The rationality and reliability of the mapping technique used in the numerical simulation were validated by a comparison between the experiments and the numerical simulation. The findings showed that the numerical simulation result was consistent with the experimental blast attenuation, meaning the numerical mapping technique could effectively enhance the simulation accuracy and could reflect the experimental blast wave propagation.
The influence of long-range transport (LRT) of air pollutants on neighboring regions and countries has been documented. The magnitude of LRT aerosols and related constituents can misdirect control strategies for local air quality management. In this study, we aimed to quantify PM2.5 (diameter less than 2.5 mu m, PM2.5) and associated metals derived from local sources and LRT in different geographic locations in Taiwan using advanced receptor models. We collected daily PM2.5 samples (n =similar to 1000) and analyzed 28 metals every three days from 2016 to 2018 in the northern, central-south, eastern, and southern areas of Taiwan. We first used a machine learning technique with a cluster algorithm coupled with a backward trajectory to classify local, regional, and LRT-related aerosols. We then quantified the source contributions with a positive matrix factorization (PMF) model for Taiwan weighted by region-specific populations. The northern and eastern regions were found to be more vulnerable to LRT-related PM(2.5 )and metals than the central-south and southern regions in Taiwan. The LRT increased Pb and As concentrations by 90-200% and similar to 40% in the northern and central-south regions. Ambient PM2.5-metals mainly originated from local traffic-related emissions in the northern, central-south, and southern regions, whereas oil combustion was the primary source of PM2.5-metals in the eastern region. By subtracting the influence from the LRT, the contributions of domestic emission sources to ambient PM2.5 metals in Taiwan were 35% from traffic-related emission, 17% from non-ferrous metallurgy, 13% from iron ore and steel factories, 12% from coal combustion, 12% from oil combustion, 10% from incinerator emissions, and < 1% from cement manufacturing emissions. This study proposed an advanced method for refining local source contributions to ambient PM2.5 metals in Taiwan, which provides useful information on regional control strategies.
The aim of this study was to examine the effects of different agility training methods on skill-related physical capabilities in young volleyball players. Twenty-seven young female volleyball players were randomly assigned to a shuttle-run training group (STG, n = 9), an agility-ladder training group (ATG, n = 9), and a control group (CG, n = 9). The intervention program was carried out three times a week for six weeks. Before and after the training period, participants’ 10 m sprint (10 MS), agility T-test, and digging agility test (DAT) performances were assessed. Within-group analysis showed significant improvements (p < 0.05) in the DAT, agility T-test, and 10 MS performance from pre- to post-test for the STG (6.08%, 2.64%, and 5.68%, respectively) and ATG (4.05%, 3.28%, and 3.27%, respectively). In the group analysis, there were significant differences (p < 0.05) between the STG and CG in the DAT and agility T-test. The STG and ATG were significantly superior to the CG in the 10 MS (p < 0.05). In conclusion, the results indicate that appropriate agility training can enhance the agility of lateral movements and speed of sprinting, as well as enable players to rapidly complete movements during a moving defense.
The micro-injection molding is used to fabricate ultra-thin polymeric components used in optoelectronics and biotechnology. Due to the extremely high flow resistance and fast heat transfer, ultra-thin parts is difficult to mold. In this study, a lab-made impact type micro-injection machine and a rapid heating/cooling system are used to perform the micro-injection molding. A mold with test-sheet cavities of thickness 100 lm and 200 lm are constructed. The molding capacity and the effects of processing conditions are systematically investigated. The processing conditions include the mold temperature, air pressure of accelerating cylinder, and air pressure of packing cylinder. The thicker parts have larger operation window. The high mold temperature reduces the area of short shot but induces more shrinkage and sink mark. The increase of air pressure in accelerating and packing cylinders can effectively reduce shrinkage.
During peak hours, retail employees might be busy and unable to promptly fill the void on shelves and racks, which often leads to customers being unable to complete their purchases as they expect. To tackle this problem, we combine image recognition software with the application of ArcMAP on the product replenishment alert system. The study aims to promptly alert retail employees of the vacancies, addressing the challenges of the traditional manual replenishment process. With technological advances, the retail industry has undergone significant transformation through the development of shelf-scanning robots and the establishment of automated management techniques. The phenomenon represents the global value replenishment systems and automated management techniques, both domestically and internationally. Most of the current research on the replenishment system focuses on robot development. Nonetheless, in this research, we combine a camera and the program Free Video to JPG Converter, ensuring merchandise is well-stocked, well-maintained, and properly rotated on the shelves. The camera can accurately detect the trajectory and vacancies of goods. The program, Free Video to JPG Converter, processes the identification and recognition, converting the collected MP4 files to recognized JPEG files, and then imports them to the ArcMAP program. It analyzes the features of the items, and then identifies and recognizes the images. The function of this system is to meet the immediacy, reduce labor costs, and avoid profit loss caused by blind spots in merchandise display. As a result, consumers have access to their purchases. With intelligent technology, this research is not only intended to increase economic value but also create a win-win situation for both the customer and the store.
