The Intra-Tidal Characteristics of Tidal Front and Their Spring–Neap Tidal and Seasonal Variations in Bungo Channel, Japan

The intra-tidal variations of a tidal front in Bungo Channel, Japan and their dependence on the spring–neap tidal cycle and month were analyzed utilizing high-resolution (~2 km) hourly sea surface temperature (SST) data obtained from a Himawari-8 geostationary satellite from April 2016 to August 2020. A gradient-based front detection method was utilized to define the position and intensity of the front. Similar to previous ship-based studies, SST data were utilized to identify tidal fronts between a well-mixed strait and its surrounding stratified area. The hourly SST data confirmed the theoretical intra-tidal movement of the tidal front, which is mainly controlled by tidal current advection. Notably, the intensity of the front increases during the ebb current phase, which carries the front toward the stratified area, but decreases during the flood current phase that drives the front in the opposite direction. Due to a strong dependence on tidal currents, the intra-tidal variations appear in a fortnight cycle, and the fortnightly variations of the front are dependent on the month in which the background stratification and residual current changes occur. Additionally, tidal current convergence and divergence are posited to cause tidal front intensification and weakening.

UNDERWATER GROUND MAPPING FOR FLOOD DISASTER USING ULTRASONIC SENSOR

Search and Rescue (SAR) team used dip stick to measure the water depth and identify the badly eroded area and a guide line will be placed to assist them. However, ground erosion is unpredictable coupled with unknown sizes make the SAR task more difficult thus posing grave danger to SAR team in action. Therefore, this current method is no longer reliable because the flood current will swipe it away and rendered the guide line to be unfeasible over time consuming. A system proposed in this study was developed using ultrasonic sensor array to reconstruct the ground map in flood area. It consists of several sensor arrays to collect the underwater depth information and convert them into mapping data before relaying them to ground station. The results then will help the SAR team to identify the safe path to reach for the flood victims. The factor to focus on is the depth of the flood, the current flow and the medium that the wave will go through. The current flow will be the main threat because the sensor needs to be on the right angle to get the accurate reading. The data then will be transfer to excel to start the mapping for underwater ground. Based on the result from the prototype testing conducted using water tank, sensors can be installed to get wider map view and mapping can be improved by using multi-angle shapes for it to be more accurate in flood disaster.

Enabling the democratization of the genomics revolution with a fully integrated web-based bioinformatics platform

Continued advancements in sequencing technologies have fueled the development of new sequencing applications and promise to flood current databases with raw data. A number of factors prevent the seamless and easy use of these data, including the breadth of project goals, the wide array of tools that individually perform fractions of any given analysis, the large number of associated software/hardware dependencies, and the detailed expertise required to perform these analyses. To address these issues, we have developed an intuitive web-based environment with a wide assortment of integrated and cutting-edge bioinformatics tools. These preconfigured workflows provide even novice next-generation sequencing users with the ability to perform many complex analyses with only a few mouse clicks, and, within the context of the same environment, to visualize and further interrogate their results. This bioinformatics platform is an initial attempt at Empowering the Development of Genomics Expertise (EDGE) in a wide range of applications.

Tide distortion and attenuation in an Amazonian tidal river

The present study seeks to evaluate tidal propagation in the Guamá-Capim river system, in the Amazonian region, considering hydrodynamic and geomorphological aspects. Available data sets on fluvial discharge and water level variations were considered, besides several methods of measuring the tides (currents, water levels and discharges) recorded at different stations and in different periods. The main point argued is that fluvial discharge is the key-factor in tidal distortion and tidal bore formation in the system investigated, whereas the low relief of the area would be the main factor contributing to landward tidal incursion. The results show an impressive upward tidal incursion of more than 200 km, including substantial distortion -increasing upstream -of the tidal wave, of which the ebb phase lasts up to 5 hours longer than the flood, including higher flood current velocities as far as 161 km upstream. Generally, only hyposynchronous tidal response was observed. Seasonally, the fluvial discharge varies about 10 times in the Guamá and 4 times in the Capim River. The increase of the fluvial discharge results in an increasing distortion of the tide, besides a weak increase of the attenuation. During high fluvial discharge periods in conjunction with equinoctial tides (e.g. March-April), a tidal bore occurs in the system, also increased by the generally low relief. Therefore, the conclusions include: low relief and the distortion related to high fluvial discharges are the main factors controlling tidal propagation along the system and tidal bore formation. Furthermore, the system could be classified as a tidal river, in which massive regional fresh water input results in virtually non-existent salinity throughout the Guamá-Capim system.

Suspended Sediment Transport in Lianyungang Nearshore Area

Hydrological observations at 13-19 stations were conducted synchronically in Lianyungang nearshore area during the spring and half tide in winter and summer respectively. Data of suspended sediment concentrations (SSC), currents and water levels at observation stations were used to study the suspended sediment transport by the method of mechanism decomposition. The advection transport plays an important role during the whole observations, with the direction generally same to the flood current. The tidal pumping transport plays a significant role in the nearshore area, which is the main factor for the periodical variation of SSC. The direction of the tidal pumping transport is mainly toward the land, which indicates that the periodic component of SSC is transport to the land with the form of peaks in the bottom layer. The results may help to improve understanding of the coastal engineering and environmental applications related to sediment transport.

Analysis on the Tidal Current Characteristics of the Caofeidian Sea Area

Caofeidian harbor is a large size deep-water harbor currently under construction in the Bohai Bay, the eastern coast of north China. The construction began in 2003. The characteristics of tides and tidal currents in the Caofeidian area are analyzed with field data from comprehensive field observations from 2008 to 2010. The field observations and analysis show that the tide is the irregular semi-diurnal and tidal current is characterized as a type of reverse flow with moving west during flood tides and east during ebb tides. In general, the flood current is slightly stronger than the ebb current, and the strongest tidal current appears in the Caofeidian foreland, which is the predominant driving force to maintain the deep water depth.