43results about "Ice breakers" patented technology

The application provides an electromagnetic resonance-based submarine surfacing ice-breaking auxiliary device and an ice-breaking method thereof, and belongs to the field of submarine surfacing ice breaking in polar regions. The device solves the problems of the prior ice-breaking method, i.e., the method requires high strength of the submarine structure, causes great loss of the submarine shell, and consumes a large amount of resources and energy. The device comprises a mounting platform, a resonance system and a hook claw. The mounting platform is arranged on the submarine shell. The top of the resonance system is connected with the hook claw. The resonance system is arranged in the mounting platform. The resonance system comprises a magnetic end, a spring and a magnetic piece. The spring is arranged between the magnetic end and the magnetic piece. The magnetic end and the magnetic piece are respectively arranged at the lower end and the upper end of the mounting platform. The magnetic piece is connected with the hook claw. The device is mainly used for submarine surfacing ice breaking.

The application discloses a bidirectional ice-breaking transport ship with open water performance, wherein the lower bow part of the bow of the ship is a small ball bow, the lower ice belt waterline is located on the upper half of the small ball bow, the outer surfaces of the upper bow part, the middle bow part and the lower bow part are streamlined, an ice discharge groove is arranged below the stern plate of the stern of the ship, the ice discharge groove is divided into two symmetrical halves by the centerline of the ship, the intersection line of the ice discharge groove and the ice-breaking stern is the stern post, the included angle between the stern post and the centerline of the ship is not greater than 30 DEG, a pod platform is arranged at the position close to the keel of the stern post, a triangular transition plate is arranged at the position close to the stern of the ship, the transition plate connects the end of the ice discharge groove and the ice-breaking stern with the stern plate, the distance between the two stern posts on the two sides of the ice discharge groove gradually increases from the stern of the ship to the keel direction, and the end of the stern post close to the transition plate is higher than the other end. The structure of the bidirectional ice-breaking transport ship has the open water performance under ballast water and the bow ice-breaking performance under the lower ice belt waterline, the bow of the ship has the ability of breaking thin ice, the stern of the ship has the ability of breaking medium heavy ice, and the bidirectional ice-breaking transport ship has important significance.

The application belongs to the technical field of law enforcement boats, and particularly relates to a steel-glass mixed high-speed law enforcement boat, which comprises a high-speed law enforcement boat body, the upper surface of the bow deck of the high-speed law enforcement boat body is fixedly connected with a hollow leveling block, the upper surface of the hollow leveling block is fixedly connected with an air extraction pump and a protective cover through connecting bolts, the air outlet end of the air extraction pump is fixedly communicated with the upper surface of the hollow leveling block, the outer wall of the protective cover is provided with a threaded hole, and the hole wall of the threaded hole is sealingly connected with an air inlet filtering mechanism. The steel-glass mixed high-speed law enforcement boat has the function of adjusting the buoyancy, thereby the water depth can be adjusted, the running resistance of the high-speed law enforcement boat is reduced as much as possible, the high-speed law enforcement boat has the functions of overload early warning and breaking thin ice layer, the high-speed running performance and protection capability of the high-speed law enforcement boat can be effectively improved, and the safety and reliability of the high-speed law enforcement boat running can be improved.

The invention discloses an ice sailing ship. The present invention relates to a ship for sailing in an ice region, comprising: a skeg formed at the lower part of a stern; and the echo depth finder is arranged on the skeg and is configured to emit ultrasonic pulses to the seabed, receive the ultrasonic pulses reflected back from the seabed and calculate the depth of the seabed based on the time required for returning the ultrasonic pulses.

The invention relates to the field of sea ice thickness measurement, in particular to a sea ice thickness measuring device based on an icebreaker, which comprises a mounting part, an outward extending part is arranged in the mounting part, a micro moving part is arranged in the outward extending part, a lifting part is arranged in the micro moving part, a measuring part is arranged in the lifting part, and the measuring part is provided with a snow cleaning chassis. The bottom of the probe rod is fixedly connected with six scrapers which are circumferentially distributed, the scrapers are used for rapidly cleaning a snow accumulation layer and floating ice impurities in a to-be-measured area, the surface of the ice layer is completely exposed, when the probe rod makes contact with the ice layer, a signal is immediately fed back to an external control assembly, the downward moving cylinder body is controlled to stop descending, and it is ensured that the ice thickness measurer only conducts thickness measurement from the surface of the ice layer. And the problems that the ice layer and the accumulated snow layer are difficult to effectively distinguish and the accumulated snow thickness is easy to be included into the sea ice thickness measurement result by utilizing an intelligent sensor and a sound wave type measurement technology are effectively avoided.

System (100) for maneuvering ships in icy waters, comprising: - an electronic control unit mounted inside a compartment of a ship (50); - a driving means (101), connected to the electronic control unit, consisting of telescopic modules; - a lifting device, connected to the driving means (101) and to the electronic control unit, configured to activate said driving means (101). The driving means (101) is housed in correspondence with the stern portion (51) of the ship (50) and is configured, following the activation by means of the lifting device, to come out from said compartment and extend along the surface of the water in a substantially circular shape to surround substantially an entire lower portion of the hull of the ship (50).

This invention proposes an icebreaking device, vessel, and method combining jet-resonance technology for ice-trapped vessels, relating to the field of polar icebreaking technology. It addresses the problem of conventionally powered vessels or icebreakers with low ice levels struggling to break through ice in areas with ice thickness greater than 1.2 meters. It includes a hoisting platform, a jet icebreaking module, a resonant icebreaking module, and an attachment stabilization module. The hoisting platform is used for assembly with an external crane. The jet icebreaking module outputs water jets to break the ice. The resonant icebreaking module induces resonance in the ice layer. The attachment stabilization module includes a helical anchor bolt and a power mechanism. The power mechanism drives the helical anchor bolt to rotate relative to the hoisting platform, and the helical anchor bolt drills into the ice surface to fix the hoisting platform. It is primarily used on polar vessels to break through ice and escape when a vessel is trapped.

A sea ice habitat restoration system is configured to rapidly extract pack ice and raft it onto level ice to establish disturbance corridors that augment the ecological carrying capacity and resistance to continuing climate change. The deployable system is configured to be mounted on an icebreaking ship and includes a inclined-plane ice ramp supported by an ice rafting device. The system applies a hogging moment to the extracted sea ice and laterally rafts it with minimal damage, facilitating the restoration of sea ice habitats of threatened ice-obligate and ice-associated species. This ship-mounted version produces significantly greater volumes, additional vertically and horizontally arranged layers, and more widely distributed composite masses of freeze-bonded rafted ice over the course of a w inter compared to the singly rafted ice passively produced by the moored version referenced herein.

This utility model provides a multifunctional floating platform for fire and water rescue, belonging to the field of emergency rescue equipment technology. It addresses the problem that existing methods require breaking ice while approaching trapped personnel, which is cumbersome and affects rescue efficiency. The platform includes a main body, a rescue anti-slip mat, an anti-capsulation hull, a multifunctional rescue mechanism, and a rescue conversion mechanism. The rescue anti-slip mat is fixedly connected to the top of the main body. The marking drive box is fixedly connected to the upper rear end of the rescue anti-slip mat. The anti-capsulation hulls are fixedly connected to the lower left and right sides of the main body. Rescue limiting blocks are fixedly connected to the lower part of the anti-capsulation hull. The multifunctional rescue mechanism is located on the outside of the main body. The rescue conversion mechanism is located below the anti-capsulation hull, allowing for rapid assembly and eliminating the need to break ice while approaching or to navigate the ice surface before inflating the platform, thus simplifying the pre-rescue preparation process.

The graded ice-collision-resistant protection structure comprises a floating base platform and an anti-collision device, the floating base platform is installed below a fan tower and supports the fan tower, and the floating fan is installed on the fan tower; the three anti-collision devices are arranged on the periphery of the floating foundation platform after being enclosed into a triangle; the anti-collision device comprises an icebreaking assembly and a connecting assembly. Three second supporting columns are arranged at the bottom of the floating foundation platform, a triangle is defined by the three connecting assemblies, and the three inner corners of the triangle are connected with the three second supporting columns of the floating foundation platform through the buffering assemblies respectively; when an ice layer collides with the flow guide cover, the crushing roller is rotated to break floating ice in advance through the crushing nails, impact energy is reduced, large ice layer collision is prevented, the honeycomb buffer layer absorbs the impact energy, the flow guide cover and the supporting frame move synchronously, when the supporting frame moves, the fixing column compresses the spring for buffering, the damper is automatically started when exceeding a threshold value, and graded ice resistance of the floating foundation platform is achieved.

The application belongs to the technical field of ships, and particularly relates to an ice-breaking ship with a tail fin ice-breaking edge structure, which comprises an ice-breaking ship body, a bottom bin is arranged in the head of the ice-breaking ship body, and an ice-breaking auxiliary mechanism is hingedly arranged in the bottom bin; the ice-breaking auxiliary mechanism comprises an ice-contacting arm as a trigger component, a release arm as an execution component and a connecting shaft, the ice-contacting arm and the release arm are connected to form an L-shaped lever structure; the ice-breaking auxiliary mechanism is contacted with the ice layer to release the high-efficiency release of the huge deadweight energy of the ship body with small mechanical energy input, and the peak impact load that the ship body may bear when crushing the ice layer is reduced due to the pre-weakening of the ice layer, which helps to prolong the structural life of the ship body, the local damage effect based on the ice-breaking auxiliary mechanism can effectively weaken the ice layer structure, thereby effectively weakening the edge structure of the ice layer, improving the ice-breaking efficiency of the ice-breaking ship body, crushing the ice block of the impact tail fin and protecting the pod propeller.

The utility model discloses a kind of ice prevention devices on full-rotation rudder propeller of ice area navigation ship, belong to ship propeller technical field, including box, the box is provided with rudder column, the rudder column is connected with ship body;Icebreaking cone, the icebreaking cone quantity is multiple and evenly distributed in the front end of the box, to carry out icebreaking treatment;Hub, the hub is located in the front end of the box, a plurality of blades are provided on the hub, to push ship body;Guide piece, the guide piece is connected with the box by a plurality of reinforcing ribs, the guide piece is located between the icebreaking cone and the hub, the guide piece is horn shape structure body.The utility model does not need to use net-shaped protective structure to protect blade, adopts icebreaking cone, reinforcing rib and guide piece to be arranged in echelon in navigation direction, and additionally add icebreaking ice knife, effectively avoid the phenomenon of ice jam, realize the function of icebreaking, ice separation and lateral protection.

The invention discloses a rubber dinghy for water rescue, and relates to the technical field of water rescue equipment, the rubber dinghy comprises a rubber dinghy body, the rubber dinghy body is of a three-layer composite structure comprising an inner layer, a middle layer and a contact layer, the rear side of the rubber dinghy body is provided with an outboard outboard engine and a propeller, and the outboard outboard engine is fixedly installed on the rear side of the rubber dinghy body; the output end of the outboard outboard engine is in transmission connection with a propeller, a control seat is fixedly arranged at the position, corresponding to the control steering wheel, in the rubber dinghy body, a rear transverse seat plate used for bearing rescue workers is fixedly installed on the rear side of the control seat, and an icebreaking assembly is integrated at the bottom of the front side of the rubber dinghy body. The ice breaking assembly comprises a driving mechanism, a transmission mechanism and an ice breaking mechanism. Through cooperation of the icebreaking assembly and the outboard outboard engine, the rubber boat can rapidly advance in an open water area and can flexibly break ice in an iced water area, the use scene limitation of a traditional rescue rubber boat is broken through, and the practicability and reliability of rescue operation are improved.

The present disclosure relates to methods, apparatuses, and systems for unmanned underwater vehicles capable of operation in the Arctic region. An example unmanned underwater vehicle includes: a hull; one or more guide rails extending from the hull and attached to the hull by one or more legs; a vertically-deployed mast, wherein the vertically-deployed mast is configured to penetrate through an ice sheet; and a communications antenna, wherein the communications antenna is deployed with the vertically-deployed mast and enables communication above the ice sheet. The dorsally-located guide rails of an example define an extended position and a retracted position, wherein the guide rails disposed in the extended position are disposed further from the hull than the guide rails disposed in the retracted position. Embodiments described herein include systems employing air-deployable buoys, water-deployed buoys and small UUVs, and ice-penetrating buoys to support communications in the Arctic region.

The invention discloses an intelligent propulsion system of a polar region icebreaker. A low-speed motor direct-driven propulsion system of the icebreaker is used for providing propulsion power required by icebreaking navigation and bearing torque, thrust and radial force generated by ice paddle impact in ice region navigation; the ice load propelling system intelligent monitoring system is connected with the icebreaker low-speed motor direct-drive propelling system and used for monitoring ice loads borne by the propelling system and movement related parameters in real time, and the local ice thickness measurement data supporting system is used for obtaining local ice thickness data of a navigation area. The propulsion system dynamic characteristic decision analysis system is connected with the ice load propulsion system intelligent monitoring system and the local ice thickness measurement data support system, and is used for monitoring the local ice thickness based on the load and motion monitoring data of the propulsion system and the local ice thickness data. Decision analysis is carried out on the dynamic operation characteristics of the propelling system, a regulation and control instruction is output and fed back to the icebreaker low-speed motor direct-drive propelling system, and intelligent cooperative operation of the whole propelling system is achieved.

The invention relates to the technical field of icebreaking devices, and provides an underwater icebreaking device and an icebreaking system.The underwater icebreaking device comprises a barrel with a containing cavity, and one end of the barrel is used for icebreaking; the two eccentric parts are arranged in the containing cavity at intervals in the radial direction of the cylinder body, the two eccentric parts can rotate in opposite directions at the same time relative to the cylinder body, and the rotating axes of the two eccentric parts are parallel to the radial direction of the cylinder body and are perpendicular to the arrangement direction of the two eccentric parts; the driving assembly is arranged in the containing cavity and used for driving the two eccentric parts to rotate; the first transmission assembly is arranged between the driving assembly and one eccentric part; the second transmission assembly is arranged between the driving assembly and the other eccentric part; the driving part drives the two eccentric wheels to rotate reversely at the same time through the first transmission assembly and the second transmission assembly so as to drive the barrel to move in a reciprocating mode in the height direction of the barrel. Through the technical scheme provided by the invention, the icebreaking efficiency and the use cost of the device are both considered.

This invention relates to the field of ship icebreaking technology and discloses a squeeze-triggered impact-type icebreaking device, comprising: a base for fixing the icebreaking device to the lower surface of the hull; a slider housing with a guide rail on its outer side, the slider housing being connected to the inner wall of the base via the guide rail; an icebreaking mechanism disposed inside the slider housing, including a spike and a temperature sensor, the temperature sensor being embedded inside the spike body; a rotary opening and closing mechanism disposed inside the slider housing, which opens and releases the icebreaking mechanism when triggered; an electromagnet A is fixedly disposed between the icebreaking mechanism and the integrated module of the circuit control system, and an electromagnet B is fixedly disposed on the icebreaking mechanism, the electromagnet B moving up and down with the icebreaking mechanism. This invention uses the interaction of electromagnets driven by alternating current as a power source. When the ship is subjected to squeezing force from below, a current is generated, providing a linear impact force to the spike to achieve icebreaking.

The utility model discloses a multifunctional ship bottom icebreaking device, and particularly relates to the field of ship bottom icebreaking, which comprises a ship body, a bow arranged at the front end of the ship body, a connecting piece arranged on the surface of the bow, an icebreaking cone arranged on the surface of the connecting piece, a mounting piece arranged at the bottom of the icebreaking cone, and a supporting plate arranged on the surface of the mounting piece. The ship body is provided with a supporting plate, the top end of the supporting plate is provided with a plurality of sets of telescopic devices, the top ends of the telescopic devices are provided with icebreaking hammers, and the icebreaking hammers are used for breaking the ice surface in front of the ship body. Therefore, the bottom of the ice surface is hammered through the ice breaking hammer, then the ice surface is easily broken through the ice breaking cone arranged in cooperation with the prow, when the ice breaking hammer needs to be replaced, the movable ring is rotated, the clamping plate is pushed to be separated from the clamping groove through the trough of the movable ring, so that the connecting plate can move in the connecting groove, and the ice breaking hammer is taken out and replaced.

The invention discloses an ice region floating platform safety operation management method, and relates to the technical field of ice region floating platform safety operation, and the method comprises the steps: determining an operation point region, a near-field region and a far-field region of a floating platform based on environment parameters, structure parameters and operation parameters of the floating platform, and performance parameters of an icebreaking operation and maintenance ship; the structure of the platform near the waterline is optimized in the operation point area; carrying out icebreaking operation in a near-field area by utilizing an icebreaking operation and maintenance ship; an ice-resistant device is arranged in a far-field area in advance to pre-crush large-scale sea ice. According to the method, the operation safety of the floating platform in the ice region is guaranteed in a multi-means cooperative ice breaking mode, and the full-time and full-domain safe operation capacity of the floating platform in the cold region is improved.

The application discloses an ice-breaking ship with a variable-angle self-adaptive ice-breaking shear, and is applied to a high-efficiency large-area sea ice-breaking technology, and mainly applied to a high-latitude port channel and a sea area around an offshore platform near the Arctic Circle for ice-breaking and ice-clearing operation, and solves the problems of the prior art, that is, on the basis of a double-hull ice-breaking ship, the construction difficulty of the ice-breaking ship is reduced on the basis of ensuring the ice-breaking width; the ice-breaking boot is added to the double-hull ice-breaking ship, a shearing force is applied to an ice layer during ice breaking, an ice-breaking shear is formed, the ice-breaking difficulty is reduced, and the breaking degree of the ice layer is improved; the height and the inclination angle of the ice-breaking boot can be adjusted according to the actual measurement result of the ice thickness in front of the ice-breaking boot, and the adaptability of the ice-breaking ship to different ice thickness environments is improved; and the technology is installed on the ice-breaking ship in an independent cabin mode, and is convenient to maintain. The application has high feasibility, high efficiency and practicality, and has a wide application prospect in the field of ice-breaking ships.

The application belongs to the technical field of ship sea inlet structure design scheme, and particularly relates to an icebreaker sea inlet structure with ice melting and heat exchange functions, comprising a water outlet pipe base, an outer sleeve pipe, a jet pipe, a heat exchange pipeline and a grid plate frame; the water outlet pipe base is connected to the rear side of the water outlet pipe of the icebreaker, and the outer sleeve pipe is connected to the rear side of the water outlet pipe base; the jet pipe is arranged in the outer sleeve pipe; an annular drainage port is formed between the front side pipe opening of the jet pipe and the front side pipe opening of the outer sleeve pipe, the outer wall of the jet pipe and the inner wall of the outer sleeve pipe form a heat exchange channel with a rotary body structure, and the front half of the jet pipe is uniformly provided with a plurality of jet holes c; the heat exchange pipeline comprises heat exchange pipes uniformly arranged in the heat exchange channel; and the grid plate frame is buckled to the rear end pipe opening of the outer sleeve pipe. The application is mainly used for optimizing and improving the sea inlet structure, especially the water outlet structure, of various icebreakers and other ships that need to operate in a polar low temperature environment, and is used for improving the situation that the sea inlet is prone to icing and blocking in a low temperature environment.

The invention provides a jet-airbag combined submarine floating ice breaking device and method, and belongs to the field of ship equipment. The problem of low ice breaking efficiency caused by the fact that the prior art still needs to rely on more effective methods to achieve ice breaking when facing thicker ice layers is solved. It comprises a submarine main body and a bridge, the bridge is installed on the submarine main body, a retractable jet device is installed in the bridge, a gas storage cabin is installed in the submarine main body, left and right front retractable airbags are symmetrically installed on the front side of the submarine main body, left and right rear retractable airbags are symmetrically installed on the rear side of the submarine main body, and the left front retractable airbag, the right front retractable airbag, the left rear retractable airbag, the right rear retractable airbag and the retractable jet device are connected with the gas storage cabin through a gas transmission pipeline. It is mainly used for assisting ice breaking when the submarine floats.

The invention discloses a floating type offshore photovoltaic platform. Comprising a bottom frame; the first floating cylinders are mounted on the bottom frame; the top mounting frame is arranged above the bottom frame, is provided with a flexible cable and is used for mounting a photovoltaic panel; the upper ends of the stand columns are connected with the corners of the top mounting frame respectively, and the lower ends of the stand columns are connected with the corners of the bottom frame respectively; the upper ends of the reinforcing rods are connected with non-corners of the top mounting frame, and the lower ends of the reinforcing rods are connected with non-corners of the bottom frame. The vertical columns are arranged at the corners of the top mounting frame and the bottom frame, meanwhile, the reinforcing rods are additionally arranged to connect the non-corner areas of the top mounting frame and the bottom frame, and a three-dimensional supporting system of the corner vertical columns and the non-corner reinforcing rods is formed. Stress caused by sea wave impact, water flow disturbance and wind load can be dispersed, bending deformation and vibration amplitude of the top mounting frame are reduced, fatigue damage of the frame structure is avoided, and the overall structural strength of the platform is improved.

A polar ship is disclosed. The polar ship includes: a plough formed at a lower portion of a bow of the ship; and the echo depth finder is arranged on the plough and is configured to emit ultrasonic pulses to the seabed, receive the ultrasonic pulses reflected back from the seabed and calculate the depth of the seabed based on the time required for returning the ultrasonic pulses.

This utility model provides a floating ice towing device for offshore wind turbine foundations, belonging to the field of offshore wind turbine technology. It includes: a towing structure body, with two sets of first electric cylinders installed on the upper surface of the towing structure body. One set of first electric cylinder piston rods has an ice-clearing mechanism installed on its surface, and an inclined guide plate is installed on the surface of the towing structure body. The other set of first electric cylinder piston rods has a cutting mechanism and a rolling mechanism installed on both sides of their respective surfaces. This solution uses the first electric cylinders to drive the cutting mechanism, rolling mechanism, and ice-clearing mechanism for height adjustment. Subsequently, the cutting mechanism and ice-clearing mechanism can crush the floating ice in front, forming a continuous ice-breaking channel and reducing towing resistance. Simultaneously, the first electric cylinders allow for dynamic cutting to adapt to different ice thicknesses, ensuring the straightness and stability of the towing path. Furthermore, the cutting mechanism, rolling mechanism, and ice-clearing mechanism preferentially contact the floating ice, replacing the main body of the equipment in bearing the impact and reducing the probability of structural damage.

The invention belongs to the technical field of ships, and discloses a shaft paddle propelling type polar region ship with a stern collision type icebreaking function, which comprises a ship body and rudders, the ship body comprises a stern and an icebreaking piece, the upper end of an icebreaking structure of the icebreaking piece is fixed at the bottom of the stern, the lower end of the icebreaking structure is connected with supporting structures, each supporting structure is rotatably connected with one rudder, and the rudder is connected with the ship body. The distance between the rotating axis of the rudder and the stern end point of the designed waterline is 0.3 B to 0.4 B, B is the width size of the ship body, and the designed waterline intersects with the icebreaking ridges so that the rudder can be far away from an ice layer enough, and the probability that the rudder collides with the ice layer and crushed ice is reduced; the end, close to the stern direction, of the icebreaking structure is provided with an icebreaking ridge extending linearly, the included angle between the icebreaking ridge and the horizontal direction ranges from 25 degrees to 35 degrees, the icebreaking ridge and an ice layer are approximately horizontal as much as possible, the icebreaking ridge can conduct collision type icebreaking on the ice layer, compared with extrusion type icebreaking, collision type icebreaking can reduce the power needed by icebreaking, and the icebreaking efficiency is improved. And the icebreaking effect is improved.

The application provides an icebreaking structure of an icebreaker, which comprises a ship body and an icebreaking casting; the icebreaking casting is arranged below a bow of the ship body to receive an ice cutter of the ship body. The icebreaking casting protects the ship body and the ice cutter, thereby solving the technical problem of the prior art that there is no ship body and ice cutter protection structure.

The invention provides a deicing floating device and a control system. A rectangular through cavity is formed in a hull body, and the rectangular through cavity is arranged close to the stern of the hull body; the first hull fixing assembly is arranged on the bow of the hull body, and the second hull fixing assembly is arranged at the tail end of the stern of the hull body. The ship body driving mechanism is arranged at the tail end of the ship body, the ship body driving mechanism can reciprocate up and down relative to the ship body, the underwater depth can be conveniently adjusted, and the ship body driving mechanism is located between the second ship body fixing assembly and the rectangular through cavity; the frame body fixing frame is detachably arranged on the ship body, and the frame body fixing frame is located above the rectangular through cavity; one end of the flow pushing mechanism is arranged on the frame fixing frame, the other end of the flow pushing mechanism extends into the rectangular through cavity, the flow pushing mechanism can reciprocate up and down relative to the ship body, water entering and exiting and transportation are facilitated, and meanwhile the underwater working depth is adjusted. According to the deicing floating device and the control system provided by the invention, the problems that the existing deicing equipment is not suitable for deicing on an open water surface and has a single function are solved.