Some 1,700 people were killed during by the 2011 tsunami disaster in Rikuzen-Takata city of Japan's Iwate Prefecture.
To ensure early recovery from the disaster, Japan's Shimizu Corporation is working to improve the foundation of the land by using a three kilometer long belt conveyor system to transport huge amounts of sediment created by the tsunami.
"We are undertaking construction to improve the foundation. We are building an elevated land foundation by scraping off the mountain as seen over there with the heavy construction machine. This is the project to create elevated land by filling it up with sediment soil, which is transported by the belt conveyor system," said Takahisa Minesawa, Project Manager, Shimizu Corporation.
In order to protect the residents, this elevated land foundation is being built to a height where it can bear even a tsunami.
"The transportation ability of this belt conveyor is 6,000 tons per hour. If you use dump trucks to transport this amount, it will create a huge traffic problem. If dump trucks are run across the bridge every six seconds, this will cause serious deterioration in the lives of local residents. The belt conveyor is a necessary system to ensure faster progress of our construction work," said Minesawa.
The belt conveyor drives soil at a speed of 15 kilometers per hour and at a height of 20 metres.
The Shimizu Corporation is expected to complete the project in two-and-a-half years through the use of belt conveyer technology.
If the company uses trucks to transport the soil, it would take more than eight years to complete the project.
Moreover, the belt conveyer system led to the improvement of environmental degradation and also contributed to prevent accidents that might have occurred if the dump truck was to run in the city.
The mountain of sediment was 125 metres high at the time when Shimizu started construction. It is now approximately 45 metres.
Dynamite is being used for the construction of the sediment mountain that consists of hard rock. The rocks from the sediment are turned into soil, which creates ground to support the building.
"The sediment is consisting of hard rock that is called the conglomerate. While this conglomerate is carried by the belt conveyor, it will be mixed with the soil to create the very hard, firm foundation ground," said Minesawa.
The land foundation, which was created by sediment transportation, was build to elevate 12.5m of height, also in consideration of the land subsidence.
At the central control room, the work activities are monitored by 50 cameras.
For the tsunami refugees returning to their hometown, the belt conveyor will complete its mission and becomes dismantled in the autumn. The next full-scale construction will begin.
"We are at operation from seven in the morning to six in the evening. Operation is running for 10 hours every day, except for the lunch break. In addition, we are doing maintenance from 7 in the evening to 5 in the morning, so it is almost 24 hours operation," said Minesawa.
In Tokyo, the exhibition of drones attracted many. It is a revolutionary technology which contributes to future social life.
"There are various flying circumstance for drone. But main flow is the flight in free area utilizing GPS. Our technology is revolutionary. In indoor area, where GPS is not available, we utilize laser as a supplementary function. That is the characteristic of this Drone. Currently, the mission of this drone is installing camera to make air shot from sky. It is effective to collect images and any information," said Satoshi Suzuki, Visiting Assistant Professor, Autonomous Control Systems Laboratory Ltd.
"But in near future inspection of bridge, tunnel and dam will be new mission. Such activity is dangerous work in height. Next expectation to drone from industrial market is dangerous work in height where GPS is difficult to work," added Suzuki.
In this demonstration, drone can search its way to get back to starting point despite of blocking its original way.
Laser sensor enables its own master flight.
"This drone prepares laser sensor in horizontal axis and vertical axis. Combining horizontal and vertical this drone constitute 3 dimensions map. In its map drone can recognize its location. GPS helps the Drone to control its aviation," said Suzuki.
Drone could pass the space of 1.5 meters without any crash.
"In Japan, regulation by law against to drone is disputed. But development of technology is innocent and necessary. In this circumstance, relative persons should join and work together to establish safe and efficient flight for drone," added Suzuki.
Surveillance drones are now used for security purpose in many countries. In countries where flying drones are banned, there are legal ways to use commercially.
