Ministry of Transportation and Communications

The Underwater Locator Beacon (ULB), attached to flight recorders, transmits continuous signals upon water immersion to aid in recovery operations. Timely localization is critical due to the limited operational lifespans of ULBs: 30 days for DK120 (37.5 kHz) and 90 days for DK180 (8.8 kHz). This study developed a near-real-time localization system using a towed hydrophone array to detect ULB signals and dynamically adjust search operations. Field experiments were conducted off the coast of Liuqiu Island under varying ocean currents and vessel speeds to evaluate the system's performance. Results demonstrated the adaptability and stability of the system, significantly enhancing search efficiency. By incorporating real-time feedback from electronic compasses, accelerometers, and depth sensors, the heading and attitude of the towed array were accurately monitored, reducing bearing angle errors. Dynamic heading correction reduced positioning errors from 650 meters to 70 meters during operations, demonstrating the critical role of real-time attitude correction in underwater localization. The workflow integrated three key steps: (1) drop point analysis to estimate the search area using radar disappearance points and acoustic modeling, (2) near-real-time localization using TDOA-based signal processing and grid probability statistical methods, and (3) dynamic route adjustment to narrow the search area and focus resources. The DK180's 8.8 kHz signal was particularly effective in deep-sea environments, offering longer transmission ranges and higher signal-to-noise ratios than the DK120. This study's findings highlight the potential of near-real-time localization systems to improve search and rescue operations for flight recorders, enhancing both efficiency and positioning accuracy in underwater environments.

ABSTRACTThe Oryctes rhinoceros (Scarabaeidae: Coleoptera) is a common coleopteran insect in tropical and subtropical areas with many potential uses. Its larvae are commonly found in dead coconut trees and hay piles in the wild and are widely distributed in the northern hemisphere. This study investigates the environmental factors influencing the growth of Oryctes rhinoceros beetle larvae and provides valuable insights into their breeding conditions versus their potential applications. The research examined three key affecting factors of larval development over time, namely, moisture content, growth space and soil content. Results of a pretest run revealed that moisture content, but not the soil content, affected the larval survival greatly. A reasonable confinement on feed moisture (i.e., 30%–60%) was included in the later conducted three‐factor factorial experiment. At last, results of the factorial run suggested that: (1) for a consistent and massive larval breeding, environmental factors, setting moisture content at 60%, larval space at 100 cm3/larva and no soil addition, are deemed appropriate, (2) for nutritional purpose, setting moisture content at 60%, larval space at 300 cm3/larva and no soil addition are recommended, and (3) for soil pollution remediation, setting moisture content at 60%, larval space at 100 cm3/larva and a soil‐to‐feed (S/F) ratio of 2:1 is concluded. This study marks the first engineering breeding exploration of Oryctes rhinoceros larvae, offering practical recommendations for various research purposes and applications.

Transit-oriented development (TOD) is a major planning tool to promote green transport mode share. There are many previous studies in this field but with very diverse research focuses and outcomes. This study has classified the research purposes of previous studies into four categories: exploratory; potential and challenges; performance evaluation; and in-depth investigation. To identify critical factors that might influence green transport systems, a systematic literature review is delivered via a meta-analysis. Specifically, green transport mode share was set as the dependent variable and a proxy for TOD outcomes. From the model results, several key factors are identified. For example, built environment planning (e.g., pedestrian sidewalks) plays a critical role in green transport systems. The main findings of this paper can provide clear direction to current TOD, such as how to improve TOD outcomes and providing planning guidance for potential TOD.

The aim of this study is to establish an underwater towed hydrophone array detection and positioning system, which serves as a rescue device for detecting flight recorders in the event of a maritime accident. By using Time Difference of Arrival (TDOA) to calculate the azimuth of the underwater locator beacon (ULB) which is located inside the black box, the position of the flight recorder can be obtained. The underwater towed hydrophone array detection and positioning system was tested for a three-day experiment in the waters off the southwest coast of Taiwan. The azimuth of the sound source was determined by using two frequencies generated by different types of underwater locator beacons (37.5 kHz and 8.8 kHz) and post-processing. The accuracy of the positioning was achieved by controlling the depth of the underwater hydrophone array. This study can deduce the location of the underwater locator beacon through subsequent positioning analysis, which can be used by search and rescue teams in the future to improve the efficiency of the rescue process.

The shares of the domestic market of public transportation systems in Taiwan have shown a significant change since 2007 when the high-speed rail (HSR) began operating. Specifically, the passenger demands of conventional trains operated by the Taiwan Railways Administration (TRA) have been shrinking in long-distance trips but increasing in short-distance trips after the operation of the HSR system. In Taiwan, passenger rail volumes are highly dependent on the integration conditions of both the HSR and TRA stations. To analyze the impact of station integration/connection conditions on rail passenger demands, random-effects panel data models were calibrated and validated to describe the relationship between rail ridership and a vector of influence factors. Using an 11-year passenger volume dataset of both the HSR and TRA systems, the empirical study results indicated that total employment and the number of daily trains have a positive effect on rail ridership. In contrast, in- and out-of-vehicle travel times are negatively associated with rail ridership. The developed models were applied to investigate the HSR station location problem for a southern extension segment in Taiwan. The results of the scenario analysis led to suggesting that the government establish the HSR Pingtung station connected to a TRA’s minor station to maximize the total revenue of both rail systems. When establishing a new HSR station, the proposed panel data model can be applied to determine the appropriate station integration pattern that maximizes the total volume, revenue of the rail service, or both.

In urban areas, public transport can improve sustainable transport by reducing vehicles and congestion, and improving accessibility. Mass rapid transit (MRT) is especially important for large cities, such as Taipei City, Taiwan. In particular, MRT aims to improve mobility and reliability, but has limitations in providing first and last mile accessibility to final destinations or origins. Taipei City, Taiwan has introduced a public bike sharing scheme to service this gap. However, few studies have addressed how a public bike sharing scheme assists first and last mile accessibility. This study uses Taipei City as a case study to investigate this issue by comparing the demand and supply of the public bike sharing scheme, YouBike, at a detailed spatial scale. The supply of YouBike is represented by the time saving compared to walking for each identified origin and destination pair in the study area (i.e., Point of Interests (POIs) and MRT stations). The demand for YouBike is total trips from each YouBike station to a MRT station using public transport smart card data. By comparing the demand and supply for over 400 zones or villages, service gaps and areas of unbalanced service can be identified. The results show that YouBike does provide first and last mile service for the MRT network with some evidence of service mismatch in the study area, i.e., high service for low demand and vice versa. The conclusions of the paper can help cities wanting to introduce a bike sharing schemes to improve first and last mile transport.