Abstract: A rotation detector includes a motor, a current detector and a hardware processor. The motor includes coils of two or more phases and a rotor. The current detector detects currents flowing in coils of at least two phases among the coils of two or more phases. The hardware processor estimates an initial position of the rotor based on current values of the currents detected by the current detector to start the motor, controls an energization pattern on the phases to rotate and start the motor based on the estimated initial position, and determines whether the rotor stops or is rotating before completing the estimation of the initial position.

Abstract: An exemplary lock apparatus generally includes a shackle, a crossbar, a lock device, a first bolt, and a trigger. The lock device has a locked state in which the lock device retains a spindle in a spindle locking position, and an unlocked state in which the lock device does not prevent movement of the spindle to a spindle unlocking position. The first bolt is engaged with the spindle such that movement of the spindle between the spindle locking position and the spindle unlocking position drives the first bolt between a first locking position and a first unlocking position. The trigger is movably mounted in the crossbar for movement between an engagement position, in which the trigger maintains the spindle in the spindle unlocking position, and a disengagement position, in which the spindle is operable to move to the spindle locking position.

Abstract: With advanced compute capabilities and growing convergence of wireless standards, it is desirable to run multiple wireless standards, e.g., 4G, 5G NR, and Wi-Fi, on a single signal processing system, e.g., a system on a chip (SoC). Such an implementation may require simultaneously receiving and transmitting signals corresponding to each wireless standard and also signal processing according to respective requirements. Typical solutions involve providing separate hardware blocks specific to each wireless standard, which in turn requires more area on the SoC and consumes more power. Embodiments of the present disclosure provide a unified hardware that may process signals across different standards in both a transmitting direction and a receiving direction simultaneously.

Abstract: A method of detecting safe and other states of battery while electric vehicle is being driven controls an inverter to generate ripple current on the battery; ripple voltages of a plurality of battery cells are measured, voltage phase shifts between the battery cells are calculated. The battery can be analyzed as normal or otherwise according to the voltage phase shift between plurality of the battery cells. A vehicle-mounted device and a non-volatile storage medium therein, for performing the above-described method, are also disclosed.

Abstract: A multipart gripper unit for a transverse, longitudinal and/or simultaneous stretching unit is disclosed having a main part and at least two guide parts. The main part includes a base body as well as a clamping device for clamping a material web and the guide parts each comprise a base body as well as at least one guide element for guidance on a rail of the stretching unit. The base bodies of the guide parts and the base body of the main part are each manufactured as separate component parts and attached to each other.

Abstract: The invention relates to a method for automatically planning a trajectory to be followed during a medical intervention by a medical instrument targeting an anatomy of interest of a patient, said automatic planning method comprising the steps of: acquiring at least one medical image of the anatomy of interest; determining a target point on the previously acquired image; generating a set of trajectory planning parameters from the medical image of the anatomy of interest and the previously determined target point, the set of planning parameters comprising coordinates of an entry point on the medical image. The set of parameters is generated using a machine learning method of neural network type. The invention also relates to a guiding device implementing the set of planning parameters obtained.

Abstract: The present invention relates to a process for the preparation of enantiomerically enriched 3-aminopiperidine, as in particular of its R-enantiomer (R)-3-aminopiperidine. The invention also relates to an enantiomerically enriched intermediate of said process and to specific acid-addition salts of 3-aminopiperidine (hereinafter also APIP) that are useful for obtaining a single enantiomer of APIP, and to crystalline (R)-3-aminopiperidine-dihydrochloride-monohydrateand crystalline (S)-3-aminopiperidine-dihydrochloride-monohydrate.

Abstract: Provided is a wireless communication device. A PHICH reception unit determines whether a received signal in a PHICH region is an ACK signal or a NACK signal. When doing so, the PHICH reception unit does not receive a PHICH in a subframe in which a terminal monitors an E-PDCCH. A control signal reception unit outputs a retransmission prompting signal to a signal allocation unit when the signal outputted from the PHICH reception unit is a NACK signal and when a UL grant was not detected. Meanwhile, when a UL grant was detected, the control signal reception unit outputs the detected UL grant to the signal allocation unit. The signal allocation unit maps the transmission signal in accordance with the retransmission prompting signal and the UL grant and transmits the transmission signal from a wireless transmission unit.

Abstract: A bath receptor includes a water inlet, a first basin, a second basin, and a partition positioned between the first basin and the second basin. The water inlet is configured to supply water to the bath receptor. The first basin includes a first whirlpool system configured to direct water in a first direction within the first basin. The second basin includes a second whirlpool system configured to direct water in a second direction within the second basin. The second direction opposite the first direction. The partition is vertically provided along at least a portion of a height of the bath receptor.

Abstract: This disclosure provides systems, methods, and devices for wireless communication that support enhanced positioning operations using a repeater. In a first aspect, a method of wireless communication includes receiving, by the UE, an instruction from a base station (BS) to perform a first signal measurement at a first time and a second signal measurement at a second time; determining, by the UE and based on the instruction, a first signal characteristic of a first signal during the first time corresponding to a time when a first repeater is repeating the first signal from a base station; determining, by the UE and based on the instruction, a second signal characteristic of a second signal during the second time corresponding to a time when the first repeater is not repeating the second signal; and a location of the UE is determined based on the first signal characteristic and the second signal characteristic.

Abstract: A lung phantom unit for radiotherapy according to an embodiment of the present disclosure may arrange, at a location not affected by a magnetic field, a phantom driving cylinder and a driving device which may move a lung mimic and a tumor mimic in a lung simulation block. The lung phantom unit may be used for general purpose even as a phantom for MRI-based and CT image-based radiotherapy. Since lung and tumor motions are implemented by air injection, it may be possible to precisely measure the motion and volume change of a lung according to subtle changes in air pressure so that customized radiotherapy suitable for a patient having various breathing patterns is possible.

Abstract: Delivery apparatus and assemblies are shown and described. In one embodiment, a delivery apparatus includes a base having a securement track groove and a substantially opposing receiving aperture, and a central tube removably affixed about the base. The central tube may have a raised protrusion to mate within the securement track groove, a substantially opposing lip to align within the receiving aperture, and at least one elongated rib. The result is an improved hidden display and assembly for enhancing efficient, effective delivery of a hidden item inside a food item(s) or the like.

Abstract: A method, computer readable media and system for providing X2 Gateway (GW) multi-cell support, comprising: are presented. In one embodiment a method includes providing a system having a Virtual Radio Unit (VRU) in communication with a Het Net Gateway (coordinating server); exchanging non-content X2 request messages between the VRU and the coordinating server; exchanging non-content X2 response messages between the VRU and the coordinating server; and wherein the non-content X2 request messages and the X2 response messages are used to communicate multiple cells served by the VRU to the coordinating server.

Abstract: Systems, methods, apparatuses, and computer program products for mobility failure evidence-related operations. A UE may measure, record, and report a channel access waiting (CAW) time period that elapsed from having a handover-related message in a transmission buffer until a channel for transmission of the handover-related message was obtained or until an acknowledgement or negative acknowledgement from a receiver of the handover-related message was received. The CAW time period information may be provided to a network node, and the network node may control mobility robustness optimization based on the received information.

Abstract: Each storage controller comprises a first storage unit, an interface unit, and a processing unit which sends, to the interface unit, a parameter which instructs n-fold write of writing data in each of n-number of (n is a natural number of 2 or more) other storage controllers. When the interface unit receives the parameter, the interface unit executes each processing of acquiring the data from the first storage unit and storing the data in the second storage unit, generating n-number of requests of writing the data in each of n-number of the other storage controllers, storing each of the generated requests in n-number of the queues corresponding to each of n-number of the other storage controllers, and processing each request stored in each queue and transferring the data stored in the second storage unit to each of n-number of the other storage controllers.

Abstract: Methods, systems, and devices for wireless communications are described. A first user equipment (UE) may receive, from a base station, a first downlink control information (DCI) message which schedules a sidelink transmission from the first UE to a second UE on a first set of resources associated with a sidelink shared channel. The first UE may additionally receive a second DCI which indicates a second set of resources which are cancelled from the first set of resources. Based on the cancellation indication, the first UE may modify or cancel at least a portion of the sidelink transmission originally scheduled for the second UE, and may transmit the modified sidelink transmission over a portion of the first set of resources in accordance with the cancellation indication, the first DCI, and the second DCI.

Abstract: An instrument for facilitating opening of a ligating member for an orthodontic bracket. The instrument includes one tip designed to engage an opening feature on a labial side of a ligating door of the orthodontic bracket, and another tip designed to sit underneath a tie wing formed on a body of the orthodontic bracket. When the instrument is in position against the orthodontic bracket, squeezing together the handles results in the tips applying a reciprocal force on the ligating door and the bracket body to open the ligating door along the occlusal direction.

Abstract: A method for calibrating a Lidar and a positioning device, a device, and a storage medium. The method includes: acquiring a point-cloud data sequence of the Lidar and a pose data sequence of the positioning device, in which, the Lidar and the positioning device are on a same traveling device; determining first trajectory information of the Lidar and second trajectory information of the positioning device according to the point-cloud data sequence and the pose data sequence; and determining a calibration offset between the Lidar and the positioning device according to the first trajectory information and the second trajectory information, in which, a matching degree between the first trajectory information and the second trajectory information satisfies a preset matching degree condition under a trajectory information correspondence determined based on the calibration offset.

Abstract: Apparatuses, systems, and methods for UE assisted mobility management. A UE may receive, from a network, an initial list of measurement cells, filter the initial list of measurement cells based on criteria to generate an optimized cell list, perform cell measurements based on the optimized cell list, and report, to the network, cell measurements based on the optimized cell list. The criteria may be based, at least in part, on at least one of UE location, UE mobility pattern, and/or UE privacy preservation. The UE may use a geolocation and/or a mobility pattern of the UE and geolocations of cells to filter out cells. The UE may use a privacy preservation algorithm on a previously filtered list of measurement cells to filter out cells to avoid allowing the network to estimate a geolocation of the UE based on the reported measurements.

Abstract: An automatic inflator device includes a housing that houses various operational components of the automatic inflator device such as a power source that is electrically coupled to a pump. A coupling portion attached to the housing selectively secures the automatic inflator device to an inflatable object, such as an inflatable watercraft, where the automatic inflator device may remain secured even while the inflatable object remains fully operational, such as while the inflatable object is in use. The pump may be selectively energized to pump air into the inflatable object via a fluid conduit. For example, the pump may be energized or de-energized based on user input or automatically based on a measured pressure of the inflatable object. Optionally, the automatic inflator device may be incorporated into an inlet valve of the inflatable object as the inflatable object is originally manufactured.

Abstract: A semiconductor device includes a first semiconductor component including a first semiconductor substrate and a first wiring structure, and a second semiconductor component including a second semiconductor substrate and a second wiring structure. A first surface of the first semiconductor component and a second surface of the second semiconductor component are bonded together. Assuming that regions having circumferences respectively corresponding to shapes obtained by vertically projecting the first surface, the second surface, the first wiring structure, and the second wiring structure on a virtual plane are first to fourth regions, respectively, an area of the first region is smaller than an area of the second region, the entire circumference of the first region is included in the second region, an area of the fourth region is smaller than an area of the third region, and the entire circumference of the fourth region is included in the third region.

Abstract: The present invention relates to a method for forcible password change, a server register a user data and a first key, the user signs into a mobile application program according to the user data and the first key. When the login key is different from the first key, and the number of sign-ins exceeds a threshold, the server will stop the user data from signing into the mobile application; the server generates a second key and sends a notification message; a confirmation event is executed to the notification message; after execution of the confirmation event the server allows the user data and the second key to be used to open the mobile application. This method enhances the security of the user account. When it is stolen or possibly stolen, the password is quickly changed and reconfirmed to prevent the account from increasing the loss of theft.

Abstract: An electrolysis electrode includes a conductive substrate, a catalyst layer and a tantalum oxide layer. The conductive substrate includes at least titanium. The catalyst layer is provided on the conductive substrate. The catalyst layer includes platinum and iridium oxide. The tantalum oxide layer is provided on the catalyst layer. In the electrolysis electrode, the catalyst layer is partially exposed.

Abstract: User system authentication includes a service infrastructure system receiving, from the user system, an authentication request including a user account identifier, generating a first validation code by performing a hash algorithm on the user account identifier and a first timestamp associated with the authentication request, sending to an email account associated with the user account identifier, an email message including the first validation code, receiving from the user system, a verification code, in response to receiving the verification code, generating a second timestamp, validating the second timestamp, in response to determining that the second timestamp is valid, generating a second validation code by performing the hash algorithm on the user account identifier and the first timestamp associated with the authentication request, comparing the verification code and the second validation code, and authenticating the user system, in response to a determination that the verification code and the second v

Abstract: Provided is a method of manufacturing a substrate including an alignment mark, including: forming the alignment mark and a recess portion on the substrate, the alignment mark not penetrating the substrate and including a bottom portion with a lower infrared transmittance than that of a first surface and a second surface of the substrate; and aligning the substrate by orthogonally arranging predetermined positions of the first surface and the second surface of the substrate in a horizontal direction and an infrared ray camera and by image-identifying the alignment mark formed on the substrate with transmitted light of infrared rays emitted from the infrared ray camera.

Abstract: A file storage method, apparatus, device and a readable storage medium. The method includes: performing striping processing on a target file to obtain multiple target objects, and calculating fingerprint information of each target object; using a first target object and logical information of the target file to form a logical header object, and storing the logical header object in a storage system; using the fingerprint information of each second target object to determine whether the second target object has been stored in the storage system; and if the second target object has not been stored in the storage system, determining the second target object as a third target object and storing same in the storage system. According to the method, logical information of each file can be preserved, and files of some users can be prevented from being modified or deleted after deduplication is performed in the storage system.

Abstract: An agricultural implement for mounting on a U-shaped foundation frame supported on wheels for travel over a ground surface where the foundation frame includes first and second laterally spaced mounting beams fixed to and extending from a base. The implement is configured to perform an agricultural operation, to rest on the ground surface when in an idle position, and to attach to the foundation frame when in an operating position. The implement comprises a rigid implement portion configured to be attached to the first and second mounting beams at first and second beam locations remote from the base such that the first and second mounting beams are prevented from moving laterally with respect to each other.

Abstract: A cable actuated multi-pawl park lock includes an actuator, a first park lock device arranged for engaging a first gear wheel, a first cable connecting the actuator to the first park lock device, a second park lock device arranged for engaging a second gear wheel, and a second cable connecting the actuator to the second park lock device. In some example embodiments, the actuator includes an actuator housing, the first park lock device includes a first park lock housing, the first cable includes a first outer jacket having a first end fixed to the actuator housing and a second end fixed to the first park lock housing, the second park lock device includes a second park lock housing, and the second cable includes a second outer jacket having a first end fixed to the actuator housing and a second end fixed to the second park lock housing.

Abstract: A device comprises a plurality of 2D semiconductor nanostructures, a gate structure, a source region, and a drain region. The plurality of 2D semiconductor nanostructures extend in a first direction above a substrate and arranged in a second direction substantially perpendicular to the first direction. The gate structure surrounds each of the plurality of 2D semiconductor nanostructures. The source region and the drain region are respectively on opposite sides of the gate structure.

Abstract: The invention provides stable liquid formulations containing naloxone, a pharmaceutically acceptable salt or a derivative thereof. The invention further provides methods for treating opioid overdose, opioid dependence, and congenital insensitivity to pain with anhidrosis by administering the liquid formulations of the present invention intranasally to a patient in need thereof. Further, the invention provides a method of treating opioid dependence, opioid overdose, and congenital insensitivity to pain with anhidrosis by administering intranasally the naloxone formulations of the present invention.

Abstract: An information handling system includes a first memory and a baseboard management controller. The first memory stores a first firmware partition and a second firmware partition. The baseboard management controller includes a second memory. The baseboard management controller begins execution of a DM-Verity daemon, and performs periodic patrol reads of the first firmware partition. The baseboard management controller detects one or more block failures in the first firmware partition, and stores information associated with the one or more block failures in a message box of the second memory. In response to the entire first firmware partition being scanned, the baseboard management controller switches a boot partition from the first firmware partition to the second firmware partition, and initiates a reboot of the information handling system.

Abstract: A method includes forming a fin protruding from a semiconductor substrate; forming a dummy gate stack over the fin, wherein forming the dummy gate stack includes depositing a layer of amorphous material over the fin; performing an anneal process on the layer of amorphous material, wherein the anneal process recrystallizes the layer of amorphous material into a layer of polycrystalline material, wherein the anneal process includes heating the layer of amorphous material for less than one millisecond; and patterning the layer of polycrystalline material; and forming an epitaxial source/drain region in the fin adjacent the dummy gate stack; and removing the dummy gate stack and replacing the dummy gate stack with a replacement gate stack.

Abstract: Provided are a semiconductor structure and a method for forming same. The method includes the following operations. Active areas and first isolation structures disposed at intervals are provided. Second isolation structures located between adjacent active areas are provided, and top surfaces of the second isolation structures are higher than or flush with top surfaces of the active areas. A mask layer are formed, pattern openings of which expose part of the top surfaces of the active areas, and the second isolation structures are located at two opposite sides of part of the active areas. The part of the active areas exposed by the pattern openings and part of the first isolation structures are etched to form intermediate grooves at least exposing part of surfaces of the active areas. Bit line structures are formed, which are electrically connected to top surfaces exposed by the intermediate grooves.

Abstract: The present invention relates to a shower curtain for enabling a caretaker to assist a patient while also acting as a barrier between the caretaker and the patient. The shower curtain features a two-layered structure, including a fabric curtain and a plastic liner. The two-layered shower curtain is designed to be installed at an entry of a shower area. The fabric curtain and plastic liner include corresponding, generally central cut-out areas, enabling the caretaker to access the inside of the shower area for providing assistance to the patient therein, while maintaining the privacy of the patient and the safety of the caretaker. The cut-out can be of any geometric shape, and can have a transparent flexible covering. The plastic liner assists with keeping water contained within the shower area and the opaque fabric curtain maintains the privacy of the patient therein.

Abstract: System for display and presence detection are described. In some embodiments, a system may include a display and a sensor. The sensor may include a display switch, first and second display electrodes, and a light emission layer. The sensor may include a sensor switch, a sensor electrode, and an analog front end. The system may further include an external surface configured to transmit light emitted by the light emission layer toward a user.

Abstract: A valve is provided, the valve including a housing; and a valve element, the housing comprising a cylindrical bore defining an axial direction and an annular shoulder extending into the cylindrical bore, wherein the valve element is axially moveable within the cylindrical bore so as to move the valve element between a closed position in which the valve element engages with the annular shoulder and an open position in which the valve element is spaced from the annular shoulder, wherein, in the open position, fluid flowing into the valve in a first axial direction may flow through one or more apertures provided in the valve element and through the valve, wherein the valve element and the annular shoulder are configured to be in continuous contact along an annular contact surface when in the closed position so as to seal against fluid flow through the valve.

Abstract: A device for containing and dispensing fluid substances includes a container having an opening and a cavity, means for connecting a first connection element, a bag with a first part, a neck and a flange, a pump, a ring nut element suitable to connect the pump and bag to the first connection element, the first connection element including upper and lower parts delimiting a tubular through seat for housing the neck and pump, the upper part including an upper opening delimited by a wall for resting a portion of the flange and connection means suitable to cooperate with counter connection means provided for in the ring nut element, the lower part of the first connection element including a lower opening and counter connection means suitable to cooperate with the connection means, the transversal dimensions of the opening being greater than or equal to the maximum transversal dimensions of the bag.

Abstract: An image-guided robotic intervention system (“IGRIS”) may be used to perform medical procedures on patients. IGRIS provides a real-time view of patient anatomy, as well as an intended target or targets for the procedures, software that allows a user to plan an approach or trajectory path using either the image or the robotic device, software that allows a user to convert a series of 2D images into a 3D volume, and localizes the 3D volume with respect to real-time images during the procedure. IGRIS may include sensors to estimate pose of the imaging device relative to the patient to improve the performance of that software with respect to runtime, robustness, and accuracy.

Abstract: The present disclosure is directed to an ion funnel and associated systems, where the ion funnel includes a plurality of electrodes each define an opening having an associated inner dimension and receive a RF voltage. The associated inner dimensions progressively reduce in size from approximately a first inner dimension to approximately a second inner dimension. The electrodes define an internal chamber having an outer dimension that reduces at a convergence angle of approximately 30 degrees for at least a majority of a length of the internal chamber from the first inner dimension to the second inner dimension. Additional systems and methods are provided for transferring ions from an ion funnel to an ion mobility device having a pressure greater than that of the ion funnel, for selectively transferring ions from the ion funnel to the ion mobility device, and for stripping ions of certain molecules adducted thereto during transfer.

Abstract: Systems and methods for predicting a patient response to various agents and/or combinations of agents using ex vivo dosing and imaging are disclosed.

Abstract: A planar inductor may include a first coil and a second coil. The first coil may include a first trace that forms a first set of turns. The second coil may include a second trace that forms a second set of turns. A distance between the turns of the first set of turns may be equal to a distance between the turns of the second set of turns. A width of the first trace may be equal to a width of the second trace. The first coil and the second coil may be physically positioned or sized according to a/b in which a represents the width of the first trace and b represents the distance between the turns of the first set of turns.

Abstract: Strap welding system and method for welding two ends or sections of a strap around a bundle of articles or around a pressed bale. The strap welding system has a weld assembly for frictionally welding two ends of a plastic strap around a pressed bale. The weld assembly has a weld head with an upper weld jaw and a lower weld jaw, and wherein the lower weld jaw is supported, directly or indirectly, by a spring. A connecting piece for moving the lower weld jaw can optionally have a section with a connecting spring.

Abstract: Methods, systems, and apparatus, including computer programs stored on computer-readable media, for generating context data for an information card are disclosed. Upon receiving a selection of a data element to include in an information card, a plurality of dimensional view types available for the data element are determined and provided to a user. Upon receiving a selection of a dimensional view type from the plurality of dimensional view types, a set of attributes associated with the dimensional view type are determined and provided to the user. A selection of an attribute from the set of attributes is received, and a dimensional view is generated based on the selection of the dimensional view type and attribute.

Abstract: A control unit that controls a reaction force actuator that applies steering guide torque to a steering wheel: calculates, based on a curvature of a curve of a travel road in front of a vehicle detected by a camera sensor, a target steering angle for causing the vehicle to travel along the curve; calculates a target steering guide torque, based on a deviation between the target steering angle that was calculated a prediction time period earlier and an actual steering angle; adjusts a target steering guide torque such that the target steering guide torque becomes smaller as a probability that a driver performs steering operation to deviate from a lane becomes higher; and controls the reaction force actuator such that the steering guide torque becomes the target steering guide torque.

Abstract: The present technology addresses deficiencies associated with common practices for handling out of order data in a streaming data database. An aspect of the present technology is avoid storing out of order data in a snapshot but just store the out of order data as additional data linked to the temporal graph. The present technology receives out of order data and records a modification time for the data and a next modification time for the data that equals a timestamp of data previously stored in the database. If there is also data in the database for a time earlier than the timestamp of the out of order data, the earlier data is adjusted so that its next modification time matches the timestamp of the out of order data.

Abstract: The present invention relates to a cosmetic composition comprising: from 30% to 89% by weight of at least one polar oil with respect to the total weight of the composition; from 6% to 45% by weight of at least one C2-C6 aliphatic monoalcohol with respect to the total weight of the composition; from 4% to 30% by weight of hexylene glycol with respect to the total weight of the composition; from 8% to 40% by weight of dipropylene glycol with respect to the total weight of the composition; and at least one hydrophilic active agent, said composition containing less than 15% by weight of water with respect to the total weight of the composition.

Abstract: A system includes an accessory for a mobile computing device, the accessory including a body defining an interior configured to secure a mobile computing device, a communications module configured to receive an electronic command to eject a projectile, and a projectile launcher, coupled to the body, configured to eject a projectile in response to the command. The system also includes a projectile disposed in the projectile launcher.

Abstract: A device includes a processor. The processor is configured to execute instructions to: receive a request from an application to subscribe to a telemetry messaging service; grant a subscription to the telemetry messaging service, to the application based on the request; receive telemetry messages from drones over a radio access network (RAN); process the telemetry messages; and provide the processed telemetry messages to the application over the RAN.

Abstract: A method for updating a non-linear look-up table, an apparatus for updating a non-linear look-up table, and an optical receiver. The method for updating a non-linear look-up table includes: performing suppression processing on residual linear ISI contained in an input look-up table in an iterative update process of a look-up table to obtain a processed look-up table. The method eliminates adverse effects of a residual linear ISI in real time during an iterative update process of a LUT, so that a generated LUT coefficient does not continue to diverge along an iteration process, which ensures stable operation of pre-compensating on nonlinearity of an optical transmitter device.

Abstract: An accessory assembly (1) of toothed belts (9), toothed conveyor belts (9a) or portions thereof, comprising a base piece (2), a first piece (3) and a second piece (4) with respectively a first, a second and a fourth coupling part (21, 31, 41). The first and the second coupling part (21, 31) are complementary to one another so that the first piece (3) is couplable above the base piece (2) in one or more predetermined positions and the fourth and the first coupling part (41, 21) are complementary to one another so that the second piece (4) is couplable above the base piece (2) in one or more predetermined positions. The first piece (3) comprises a third coupling part (32) complementary to the fourth coupling part (41) and which faces in an opposite direction to the second coupling part (31).