月: 2024年1月

What Is a Dock Shelter?

A Dock Shelter refers to an airtight device used when trucks, containers, and similar vehicles enter factories, warehouses, or logistics centers. Its purpose is to close the gap between the loading dock and the truck bed, creating an airtight seal. The name “Dock Shelter” is derived from the visual resemblance of the shelter’s form to the entrance of a doghouse.

Through the use of Dock Shelters, it becomes possible to minimize the impact of external factors such as rain, wind, and dust, thereby enhancing cleanliness and improving hygiene management within the facility. It also prevents the occurrence of odors by blocking the flow of external air, providing an odor-resistant effect. Additionally, by controlling the influx of cold and warm air, energy loss is reduced, leading to improved energy efficiency.

Uses of Dock Shelter

Dock Shelters find applications in locations requiring controlled environments, such as warehouses and factories. These are places where greenhouse management is essential, encompassing a wide range of items like food products (including refrigerated and frozen goods), electronic devices, pharmaceuticals, apparel, and more.

There are two main types of Dock Shelters. The first is the Fixed Dock Shelter, characterized by a predetermined height of the loading dock. The second is the Mobile Dock Shelter, allowing adjustment of the loading dock height to match the height of the truck.

Due to the high level of sealing provided by Dock Shelters, preventing air leakage into the external environment, there is an energy-saving effect. This helps reduce operational power consumption in the air conditioning systems associated with Dock Shelters, leading to cost savings.

What Is a Turboprop Aircraft?

A turboprop aircraft is an aircraft equipped with a turboprop engine utilized as the power source for small or low-subsonic-speed aircraft.

A turboprop engine is a type of gas turbine engine that extracts 90% of the gas energy as rotational energy for the propeller, utilizing the remaining 10% as exhaust jet energy.

A turboprop engine consists of an air intake, a compressor, a combustion chamber, a turbine, and an exhaust port.

Air is taken in through the air intake, compressed as it passes through the compressor, and the compressed air is directed to the combustion chamber. Fuel-injected into the combustion chamber mixes with the compressed air flow, and combustion is initiated by vaporized fuel and a spark from an ignition plug. The expansion energy of the generated gas rotates the turbine connected to both the compressor and the propeller at high speed. The exhaust gas flow produced during ejection from the exhaust port accounts for approximately 10% to 25% of the total thrust generated by the engine.

Uses of Turboprop Aircraft

Turboprop engines were developed to combine the characteristics of both piston engines and jet engines during the transition from piston engine to jet engine aircraft, facilitating a smooth transition. They are employed in aircraft flying at subsonic speeds.

However, there are limitations to achieving high output due to constraints on the size and installation position of the reduction gear system relative to engine output. Additionally, limitations on the maximum speed arise from structural restrictions on propeller rotation speed and the inability to significantly reduce the aircraft’s aerodynamic resistance.

Although used extensively for low-speed aircraft in the latter half of the 20th century, and being gradually replaced by high-performance engines, turboprop aircraft are currently employed in small transport planes and twin-engine light aircraft, typically accommodating around several dozen passengers.

They are also utilized for transporting vaccines to remote islands.

What Is a Turbojet Engine?

A Turbojet Engine is an engine that derives thrust from the exhaust flow of combustion gases.

It is the most fundamental form of jet engine and was developed in the early stages of aviation. A turbojet engine is a type of gas turbine engine used in aircraft, harnessing the energy of high-temperature, high-pressure gases created within the engine to achieve high-speed jet propulsion.

By utilizing the reaction from this process, aircraft can attain substantial thrust, enabling high-speed flight.

Uses of Turbojet Engine

Turbojet engines are primarily employed in high-speed flying aircraft. Particularly, military aircraft such as fighter jets extensively adopt this engine. Additionally, the technology of turbojet engines finds applications in space exploration and missile development.

In flights below supersonic speeds, turbojet engines exhibit drawbacks such as loud exhaust noise, inefficient propulsion, and high fuel consumption. Consequently, they are predominantly used in military aircraft, disposable guided missiles, and as auxiliary engines for vertical take-off and landing aircraft designed for vertical flight.

Principle of Turbojet Engine

The principle of a turbojet engine involves the intake of air, compression, mixing with fuel for combustion, generating high-temperature, high-pressure gases, and expelling them through an exhaust turbine at high speed to generate thrust. Initially, air is taken in through the engine’s intake at the front. Subsequently, the compressed air is directed to the combustion chamber.

In the combustion chamber, fuel injected from the fuel injection system combines with compressed air and undergoes combustion through an ignition device. The resulting high-temperature, high-pressure gas passes through the exhaust turbine and is jetted rearward from the engine.

The exhaust turbine converts the energy of the high-temperature, high-pressure gas into rotational energy, driving the compression turbine. The gas that passes through the exhaust turbine is ejected at high speed through the nozzle, creating thrust for the aircraft through the reaction force. This is the fundamental principle of a turbojet engine.

Because the gas expelled from the rear of the engine is extremely powerful, it yields higher thrust. With the presence of afterburners (injecting fuel into the high-temperature exhaust gas for re-ignition), turbojet engines are employed in engines for supersonic passenger planes and jet fighters requiring supersonic travel.

Other Information on Turbojet Engine

1. Types of Gas Turbine Engines

In addition to turbojet engines, there are other types of gas turbine engines, including turbofan engines, turboprop engines, and turboshaft engines. Among these, engines that generate a jet stream (jet) and utilize its reaction for thrust are turbojet engines and turbofan engines.

Turboprop engines rotate a propeller by the rotation of the turbine and derive thrust, making them suitable for engines in propeller-driven aircraft. Turboshaft engines convert the rotation of the turbine into shaft rotation, mainly used as the power for the main rotor of helicopters.

2. Turbofan Engine

A turbofan engine has a structure where a fan is added to the front of the compressor in a turbojet engine. Turbofan engines have a structure resembling the incorporation of a turbojet engine inside a turboprop engine, where the diameter of the propeller in turboprop engines is reduced.

In turboprop engines, the airflow resulting from the rotation of the propeller is purely utilized as thrust. In contrast, in turbofan engines, the air in the outer circumferential part, larger than the diameter of the compressor, does not pass through the compressor.

The flow of air through the compressor creates a high-temperature, high-speed jet stream through the core engine, the turbojet engine. The airflow not passing through the compressor becomes a low-temperature, low-speed jet stream. Eventually, these flows mix, resulting in the equalization of jet stream speeds. This leads to an increase in the amount of jet stream, and consequently, an improvement in output compared to turbojet engines.

What Is a Safety Cone?

A Safety Cone is a conical safety device with a height of approximately 70 cm.

Primarily deployed for regulation and demarcation in areas such as roads and construction sites, the use of 700mm-high Safety Cones is stipulated in road construction, aligning with the “Road Construction Safety Facility Installation Standards.” Safety Cones fall under the category of “safety facilities,” mandated for installations to facilitate traffic guidance and access prevention.

Safety Cones come in colors not limited to red or vermilion; there are variations with black and yellow stripes or designed to blend with the surroundings, catering to different locations and purposes. Additionally, larger sizes, approximately 120 cm or 180 cm in height, exist beyond the usual dimensions.

Uses of Safety Cone

Safety Cones find utility in various applications, particularly at construction sites. They are used to manage pedestrian flow during festivals or events, and in sports, they serve as markers or guides for athletes.

Besides guiding and organizing parking lots, Safety Cones are employed to reserve spaces. They are used in driving schools for practice, and in gymkhanas, the arrangement of cones is often used to design technical courses.

Available in home improvement stores, Safety Cones are also employed in households to prevent unauthorized parking. There are also convenient, flat-foldable Safety Cones. Giant types exceeding 2 meters in height are utilized at the start of highway construction zones or turnaround points in marathons.

For enhanced visibility during nighttime, reflective sheets are sometimes applied to Safety Cones. There are also self-luminous types using LEDs, with openings at the top for inserting guide rods or signal lights to improve visibility through transmitted light.

Characteristics of Safety Cone

The hollow interior of the conical section of Safety Cones, open at the bottom, allows for space-saving stacking during transport and storage, a common feature in many types. Synthetic resin materials like rubber or polyvinyl chloride (PVC) are often used for high-speed lane regulations on highways and wind resistance. These materials exhibit high friction with road surfaces, providing weight and elasticity.

Traditional thermoplastic resins used for Safety Cones have low weather resistance. There is a possibility of cracking and damage during long-term use or in cold climates. Rubber or EVA resin is chosen for cold weather resistance. EVA has flexibility, remains relatively soft even in cold weather, and has a low probability of damage.

Types of Safety Cone

Safety Cones are mainly made of plastic or rubber, and specific examples of materials include low-density polyethylene (LDPE), high-density polyethylene (HDPE), soft polyvinyl chloride (PVC), and EVA resin. The choice of material depends on the intended use and budget.

1. Low-Density Polyethylene (LDPE)

Also known as soft polyethylene, LDPE exhibits flexibility and excellent low-temperature resistance, making it less prone to brittle fracture even in extremely cold conditions (up to -20°C). It is mechanically strong.

2. High-Density Polyethylene (HDPE)

HDPE is rigid and has excellent stiffness. Its heat resistance temperature is typically 90–110°C. It has higher crystallinity compared to LDPE, making it slightly heavier but lighter than water. Similar to LDPE, it has acid resistance, alkali resistance, and electrical insulation properties. It excels in rigidity and heat resistance compared to LDPE.

3. Soft Polyvinyl Chloride (PVC)

Soft PVC, also known as Polyvinyl Chloride (PVC), is a material softened by adding plasticizers to PVC.

4. EVA Resin

EVA resin stands for Ethylene-Vinyl Acetate copolymer. It is softer and more elastic than polyethylene, lightweight, and environmentally friendly.

What Is a Stacker?

A stacker is a type of vertical conveying equipment that has gained popularity, especially in Europe and the United States. It excels in loading tasks onto racks or truck beds using standardized pallets.

For models with a load capacity not exceeding 1 ton, operation is possible without the need for forklift driving qualifications. It enables flat movement without the need to acquire forklift operating skills, facilitating the handling of cargo within the premises.

Moreover, it is capable of safe movement even in tight spaces, offering easy positional adjustments without the need to operate a forklift.

As a replacement for tasks traditionally entrusted to forklifts, stackers are becoming a mainstay in resolving forklift queuing and congestion issues along transport routes.

Uses of Stacker

To accommodate various tasks, models with a permissible weight ranging from 980 to 1500 kg are available. Electric stackers, equipped with lithium-ion batteries that require short charging times and do not need water replenishment or maintenance, are also in existence. Some of them come with a 100V charger.

For safety assurance, designs include features such as preventing the sudden fall of the mast even when the oil pipe is cut and an emergency stop button that instantly cuts off power with a press.

Moreover, manufacturers implement safety-conscious designs like anti-rollback brake systems to prevent vehicle rollback and automatic switching to low-speed mode if the lift height exceeds the set height.

All-in-one handles, equipped with buttons and levers for driving and lifting operations, are provided for easy control at the operator’s fingertips.

What Is a Gyrocopter?

A Gyrocopter bears a striking resemblance to a helicopter, with rotors in place of fixed wings. Unlike helicopters, Gyrocopters do not have direct power to the rotors; they operate on a principle similar to a slowly descending dragonfly.

Unlike helicopters, which fly based on the lift generated from the rotation of the rotors powered by the engine, Gyrocopters rely on the principle of a dragonfly descending slowly.

The required takeoff distance is between 5 to 30 meters, and during landing, a runway of 5 to 0 meters is necessary. Due to their slow speed, they are not suitable for mass transportation and are primarily used for sports and recreational purposes.

In Japan, there are currently around 200 registered Gyrocopters, and assembly and maintenance are typically carried out by the owners under guidance. They fall into the category of “self-made aircraft” built from plans or kits.

Uses of Gyrocopter

Gyrocopters have a simple structure, different from helicopters, with models in Europe featuring cabins designed for comfort, including ventilation and heating, and being utilized for business travel.

In addition to unmatched maneuverability and stable flight performance even in rough weather conditions, Gyrocopters exhibit capabilities such as adapting to temperatures as low as -25℃ and are employed in lifesaving missions.

Furthermore, Gyrocopters find applications in various fields such as police work, agriculture, environmental surveys, wildlife poaching monitoring, aerial photography, and other professional activities tailored to specific needs.

In recent years, the development of small lithium-ion batteries has led to the creation of lighter and quieter Gyrocopters.

What Is a Cargo Net?

A Cargo Net is a type of equipment classified as “ULD (Unit Load Devices)” loaded into the cargo compartments of an aircraft. It is used to secure and protect the sides, front, and back of cargo during loading into an aircraft.

As aircraft come in various sizes, some manufacturers offer tailor-made Cargo Nets within standard specifications to accommodate the size and requirements of the cargo compartment.

When securing cargo with a Cargo Net, it is fastened using specialized straps through pallets.

Underneath the net, measures such as waterproofing and protection against theft are sometimes implemented using materials like vinyl sheets. To enhance cargo fall prevention and stabilization of fixation, multiple nets may be used for a single cargo item, and in such cases, knots are securely tied.

Uses of Cargo Net

Cargo Nets are not only utilized in aircraft cargo compartments but also for transporting baggage and in helicopter transport.

When using Cargo Nets on baggage loaded onto aviation pallets, additional measures are required to strengthen the shoulders of the cargo boxes, as they tend to bear a load.

Materials used include flame-resistant polyester weaves and incorporated sisal hemp weaves. The expected service life is three years.

Cargo Nets introduced by Japanese airlines have a service life of five years and have significantly reduced weight. They are made of ultra-high-strength polyethylene fiber called Dyneema.

Due to the material’s low moisture absorption, it is resistant to weight gain during rainy weather, effectively controlling the net’s weight increase. Lightweight design contributes to reducing annual fuel consumption.

What Is a Wingsuit?

A Wingsuit is a specialized suit with unique fabric stretched between the hands and feet. It allows for an exhilarating experience of jumping from high altitudes and gliding through the sky, akin to skydiving. The prototype was conceived in France in the 1990s, and it was introduced for sale in Finland in 1999.

Flight with a Wingsuit is often referred to as “Wingsuit Flying” or “Skyflying.” Individuals who fly with a Wingsuit are called “Wingsuit Pilots,” “Wingsuiters,” or “Skyflyers.”

This sport, falling under the category of skydiving, is popular in European countries such as Switzerland, Norway, France, and Italy, known for their numerous high cliffs and minimal regulations.

What sets it apart from traditional skydiving is the ability to change direction and maneuver freely in the air, owing to the use of a suit that provides greater control over flight. However, this increased freedom comes with a higher accident rate, resulting in fatalities each year.

Uses of Wingsuit

Typically made from nylon material that does not allow air to pass through, common and affordable Wingsuits utilize a ram-air structure, incorporating two types of nylon (thin and thick) that inflate and stiffen when air enters. This design not only increases air resistance during the dive, slowing the descent but also generates lift, enabling gliding.

Wingsuit users can achieve speeds exceeding 200 km/h. During landing, a parachute is deployed in advance to decelerate, as rapid deceleration during solo flight is challenging.

The difficulty of maneuvers such as gliding and landing increases, requiring advanced skills, making Wingsuit flying suitable for experienced skydivers who meet specific criteria. Therefore, the target audience for experiencing Wingsuit flying is limited.

Additionally, there are Wingsuits that can be equipped with airplane-like wings made of carbon fiber, known as “Wingpacks.” While these are more expensive, Wingpacks allow the attachment of jet engines, further increasing speed and travel distance. They find application primarily in military contexts.

What Is an ADS-B?

ADS-B refers to Automatic Dependent Surveillance–Broadcast, a surveillance technology that enables aircraft to track each other by using satellite positioning systems (GNSS) to determine their positions and continuously broadcast this information.

Primarily employed in air traffic control, it is a system that notifies aircraft categories, identifications, and maneuvers such as turns, climbs, and descents.

By 2015, ADS-B had become mandatory for all aircraft flying within European airspace. Both Europe and the United States decided to mandate transponder installations in December 2009.

Additional information from this system is added to the transponder response signals emitted by aircraft. By receiving and analyzing this information, including the aircraft’s position data and unique identification address obtained through GPS (Global Positioning System), trajectory data can be acquired.

Uses of ADS-B

This technology is utilized on websites such as ‘Flightradar24.’ Even the general public can easily obtain trajectory data by purchasing a receiving set. There is no obligation for adoption in Japan. Airports in Japan with many international flights can obtain over 90% of trajectory data, while regional airports with more domestic flights may see around 50%.

ADS-B enables more cost-effective, broader, and higher-precision tracking compared to traditional radar systems. It allows aircraft to exchange position information, facilitating individual situational assessments without requiring human intervention—an “entirely automatic” system.

Furthermore, controllers can issue instructions for aircraft to reduce the separation between them compared to traditional methods, aiding in managing high traffic volumes in airspace and airports. This efficiency improvement is expected to lead to cost savings and environmental conservation by reducing waiting times for approach and landing permissions.

The shared information about the surrounding traffic situation, visible to controllers, can also be shared by aircraft, and it allows for obtaining temporary flight restriction information.

ADS-B provides accurate position information even during nighttime or rainy weather. On the ground, it can accurately determine the position of vehicles equipped with ADS-B.

It proves effective in remote areas and mountainous regions with limited radar coverage. The maximum effective range is typically less than 370 km.

What Is an Electric Boat?

An electric boat refers to a type of boat (small watercraft) that operates not with an engine but with an electric motor.

Electric boats are quieter than boats powered by burning fossil fuels like diesel or heavy oil in engines. They have lower greenhouse gas emissions and can be operated at a lower cost.

In addition, compared to engines, motors have fewer components, making them less prone to breakdowns, and they experience less wear and degradation, resulting in longer life.

The motor of an electric boat is powered by batteries, and currently, enhancing battery efficiency is a challenge for manufacturers.

For boats with relatively short sailing distances, such as pleasure boats, even with the current battery efficiency, electric boats are prevalent as they can cover the required distances.

Uses of Electric Boat

Completely electric boats that do not use engines are popular for pleasure boats and sightseeing boats with short sailing distances. However, for long-distance voyages or larger vessels, fully electric boats are not widely adopted due to battery efficiency issues.

Currently, realized electric propulsion boats include diesel-electric propulsion boats and hybrid boats.

Diesel-electric propulsion boats generate electricity with a diesel generator that powers the motor, which, in turn, drives the boat’s propeller.

Hybrid propulsion boats have a battery onboard to assist the diesel generator. The battery can be activated when additional power is needed or charged with excess electricity from the diesel generator. This allows for sailing using only electricity when desired.