Shield Module Research Articles

μDOSE+: Environmental radioactivity and dose rate measurement system with active shielding boosted by machine learning

The μDOSE+ is a novel measurement system designed for environmental radioactivity measurements and trapped charge dating applications. This study describes improvements integrated into the μDOSE+ system. These enhancements include a redesigned counting chamber equipped with an active radon removal system, passive shielding and an active shielding module that is further refined by machine learning algorithms for precise pulse classification. These advancements collectively lead to a significant reduction in background in the β counting window, improved α and β counting efficiency and easier sample handling. This is demonstrated through a comparative analysis with its predecessor, the classical μDOSE system.

Mechanical design of ITER radial neutron camera Ex-Port system

The Radial Neutron Camera is an ITER diagnostic designed to measure the un-collided 14 MeV and 2.5 MeV neutrons from deuterium-tritium (DT) and deuterium-deuterium (DD) fusion reactions, through an array of detectors covering a poloidal plasma section along collimated Lines Of Sight (LOS). It is composed by two fan-shaped collimating structures viewing the plasma radially through vertical slots in the diagnostic shielding module of ITER Equatorial Port 1: the In-Port RNC, devoted to plasma edge coverage, and the Ex-Port RNC, devoted to the plasma core coverage. This paper presents an overview of the mechanical design of the Ex-Port RNC at the Preliminary Design Review (PDR) stage. The Ex-Port RNC is located in the Port Interspace and consists of a massive shielding structure hosting the detector units and two sets of collimators lying on different toroidal planes. The Ex-Port RNC design is presented both from the point of view of functional requirements (e.g. LOS positions and angles, radiation shielding, weight limitations) and of manufacturability. Finally, the Ex-port RNC structural integrity is assessed, and its design validated against the main loads and load combinations.

Nuclear analyses for the integration of ITER equatorial Port 2

The present work is devoted to nuclear analyses in support of the ITER diagnostic Equatorial Port 2 (EP#2) integration. ITER EP #2 is a diagnostic port based on the long-modular Diagnostic Shielding Module (DSM) housing the following systems: Disruption Mitigation System (DMS) in DSM#1 and #3 and X-Ray Crystal Spectroscopy Core (XRCS-Core) in DSM#2. Ensuring adequate radiation shielding is a major challenge since the diagnostic systems require several apertures from the Vacuum Vessel (VV) through the Port Interspace (PI) and up to the Port Cell (PC). In the present study, a three-dimensional MCNP model of EP#2 has been developed, starting from the latest design available from Preliminary Design Review stage (PDR), and successively integrated into the reference 40° ITER C-Model. Comprehensive nuclear analyses have been carried out employing the D1SUNED v3.1.4 code based on the MCNP Monte Carlo transport code. Relevant nuclear quantities during and at the end of plasma operations have been evaluated: i.e., neutron and gamma fluxes and energy spectra along the port from the Diagnostic First Wall (DFW) up to the Bio-Shield Plug (BP), nuclear heating, neutron damage, helium and tritium production, and shutdown dose rate. This analysis allowed the identification of potentially critical areas, and therefore, the implementation of additional shielding options aimed at reducing the neutron streaming and mitigating of the radiation field in the PI region. In this work, the results of the analyses are presented and discussed. Some solutions to mitigate nuclear loads and to improve the shielding in PI area are proposed and their impact has been assessed. Finally, some recommendations for the optimization of the design of EP#2 are provided as well.

Research and development of copper joint for ITER In-Vessel Coils

The ITER In-Vessel Coils (IVCs) are crucial components of the Tokamak fusion reactor. They are located within the vacuum vessel (VV) behind the blanket shield modules and are responsible for compensating for fast perturbations of the plasma. There are a total of 176 joints used to connect the IVCs, feeders and feedthrough. The joint structure consists of a central copper conductor, a mineral (MgO) insulation layer, and an outer stainless-steel jacket. Given the inaccessibility of the IVCs once the blanket modules are installed, the highest level of quality is required for the joints. One key item is the welding of the copper conductor which has to be done inside the VV. To address the high thermal conductivity of copper conductor and the challenging constraints working inside the VV, a preheating method by the arc of the welding head has been developed. Macro- and micro-structure examination were performed on the welding cross sections, and tensile tests were carried out to check the strength of the copper joint, which demonstrated that arc preheating does not have a significant impact on the heat-affected zone. After more than 40 welding attempts and several design updates, the copper joint has been successfully developed and can be repeatedly and successfully welded.

Countermeasure of Local Scour around Offshore Wind Power Piles

By using the CFD (Computational Fluid Dynamics) software, the RNG (Renormalization Group) turbulence model and the mud shield module are employed to establish a three-dimensional mathematical model of scouring around a wind power pile foundation. The model reliability is verified by literature results. A new wind power pile foundation protection method is proposed. The thickness of the diaphragm protective layer is 0.5 cm, 1 cm, 2 cm, 4 cm, 6 cm, 8 cm, and 10 cm. Through the numerical simulation results, the protective effect is invalid when the thickness of the protective layer is small, however, after the thickness of the protective layer exceeds a certain value, the local scouring is more significant.

Computationally efficient methodology of 3D thermal-hydraulic analysis of Diagnostic Shielding Module #2 of ITER Equatorial Port #11

The process of design justification of Diagnostic Shielding Modules (DSMs) of port plugs of the International Thermonuclear Experimental Reactor (ITER) includes a stage of thermal-hydraulic computational analysis. The ITER tokamak operates in a pulsation mode that means the nuclear heating affecting DSMs is unsteady, and transient analysis is required. Three-dimensional (3D) approaches for fully coupled thermal-hydraulic analysis, which imply simultaneous computations for fluid and solid parts of a 3D DSM model, lead typically to “heavy” numerical models being very expensive from the computational point of view, especially for transient simulations. In order to significantly reduce the consumption of computational resources, the present 3D thermal-hydraulic analysis of DSM #2 of ITER Equatorial Port #11 was performed using one-way coupling. Firstly, steady-state CFD computations of turbulent flow were performed for the front part of DSM cooling system, which is a high-density network of channels of complex geometry. Obtained in CFD analysis map of wall shear stress on surface of channels was then converted into a map of local heat transfer coefficient using a simple and conservative approach based on known empirical correlations for turbulent flow in a circular pipe. For the back part of DSM cooling system, which basically consist of many relatively long channels, an individual (single) value of heat transfer coefficient for each of the channels was directly evaluated using empirical correlation. The heat transfer coefficient maps obtained for both parts of DSM cooling system were used finally as a boundary condition in transient thermal analysis of the solid part of the DSM model. Details and justifications of the described computationally-efficient methodology are presented.

Compaction technology development for ITER In-vessel coil joints

Two types of ITER In-vessel coils (IVCs) are installed inside the vacuum vessel inner wall, behind blanket shield modules (BSMs), and near the plasma, namely: edge localized mode (ELM) and vertical stabilization (VS) coils. Overall, 27 ELM coils are distributed around the vacuum vessel inner wall, while one VS coil each is mounted above and below the plasma. Moreover, 176 IVC joints are used for joining the IVC coils, feeders, and feedthroughs, while 144 and 32 joints are used for joining the 27 ELM and two VS coils, respectively.The joints, which constitute a stainless steel (SS) sleeve, MgO insulation, and copper tube, show comparable performance to that of the conductor and can thus withstand severe conditions. Furthermore, the minimum available space for joint manufacturing is limited to 60 mm, which is a major obstacle. In joint manufacturing, two adjacent copper conductors are first welded via tungsten inert gas (TIG) welding, then the MgO insulation and sleeve will be applied. To maintain the insulation performance, the MgO insulation and SS sleeve should be compacted. Since compaction is one of the most important processes for joint manufacturing, this paper elucidates the development of compaction technology for IVC joints.

IoT Microcontroller Application Prototype as Data Transceiver from Network to USB Device

Telecommunications technology in the early 2000s until now has experienced a rapid increase. Starting with complex devices to microcomputer devices that are able to connect to the network. With the development of networking technology, it will leave behind non-network-support devices that can still be used. The existence of previous research on "The interface between the IoT microcontroller (ESP32) and the Max3421e USB Host" can be taken advantage of developing a device that can facilitate a non-support-network device into a support-network electronic device. So that non-support-network electronic devices do not become electronic waste and can also become a device that can be used in the present. In this study, a prototype of a data receiver from WiFi was designed, then the data that has been received is reorganized into rows of data that are ready to be sent to non-support-network electronic devices. This developed tool uses an ESP32 IoT microcontroller connected to the USB Host max3421e which has been packaged in the form of a USB host shield module using SPI protocol communication. The result obtained is that data from the network can be sent correctly to the USB Host max3421e via the ESP32 microcontroller.

Nuclear Analyses for the Assessment of the Loads on the ITER Radial Neutron Camera In-Port System and Evaluation of Its Measurement Performances

The radial neutron camera (RNC) is a key ITER diagnostic system designed to measure the uncollided 14- and 2.5-MeV neutrons from deuterium–tritium (DT) and deuterium–deuterium (DD) fusion reactions, through an array of detectors covering a full poloidal plasma section along collimated lines of sight (LoS). Its main objective is the assessment of the neutron emissivity/ <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\alpha $ </tex-math></inline-formula> source profile and the total neutron source strength, providing spatially resolved measurements of several parameters needed for fusion power estimation, plasma control, and plasma physics studies. The present RNC layout is composed of two fan-shaped collimating structures viewing the plasma radially through vertical slots in the diagnostic shielding module (DSM) of ITER Equatorial Port 1 (EP01): the ex-port subsystem and the in-port one. The ex-port subsystem, devoted to the plasma core coverage, extends from the Port Interspace to the Bioshield Plug: it consists of a massive shielding unit hosting two sets of collimators lying on different toroidal planes, leading to a total of 16 interleaved LoS. The in-port system consists of a cassette, integrated inside the port plug DSM, containing two detectors per each of the six LoS looking at the plasma edges. The in-port system must guarantee the required measurement performances in critical operating conditions in terms of high radiation levels, given its proximity to the plasma neutron source. This article presents an updated neutronic analysis based on the latest design of the in-port system and port plug. It has been performed by means of the Monte Carlo MCNP code and provides nuclear loads on the in-port RNC during normal operating conditions (NOC) and inputs for the measurement performance analysis.

Nuclear Analysis for the Upper Ports in the NB Cell in ITER

In International Thermonuclear Experimental Reactor (ITER), 14 upper ports (UPs) are allocated for diagnostic systems mounted into the port plug. The upper port plug (UPP) consists of the port plug (PP) structure, diagnostic shield module (DSM), and diagnostic first wall (DFW). One of the main functions of the UPP is to provide the neutron shielding to reduce the radiation level in port interspace and the nuclear loads on the superconducting coils. In this work, the nuclear analysis of the UPs #4–#7 that are located in the neutral beam cell is presented. Two configurations have been analyzed with Monte Carlo N-Particle (MCNP) code: the generic UPP design of full shielding (22 tons) and a light version (18 tons) with reduced shielding. The UPP MCNP models have been developed on the basis of latest design files and integrated in a 120° neutral beam injection (NBI) sector extracted from E-lite. Calculations have been performed to evaluate the neutron flux at the port interspace, the nuclear heating of the PP and toroidal field (TF)/poloidal field (PF) coils (TFC/PFC), the neutron flux, and damage for the electrical feedthrough installed on the closure plate with D1SUNED v3.1.4 code. The impact of crosstalk with NBI and neighboring ports has been assessed for neutron flux and shutdown dose rate (SDDR) at 12 days after shutdown. The results of this analysis showed that the impact of the additional shielding of the 22 tons model compared to the 18 tons model is small and limited in space: the fluxes and damage at the electrical feedthrough are about 40%–50% smaller with additional shielding. Analyses enhanced a large radiation crosstalk with NBI ports and a large streaming through the gaps of UPPs.

3D printed polylactic acid/graphene nanocomposites with tailored multifunctionality towards superior thermal management and high-efficient electromagnetic interference shielding

The relative lack of printable materials with tailored functionalities limits the development of three-dimensional (3D) printing techniques. Herein, a promising multifunctional filament was fabricated by incorporating graphene nanosheets (GNs) into polylactic matrix via a solution-blending method. With this strategy, the uniform-distributed GNs were obtained in the matrix, even with a high GNs concentration (9.08 vol%). The resultant nanocomposites exhibited desired functionalities, that the thermal conductivity (Tc) was up to 3.22 W/m·k, more than ten times that of pure one (0.25 W/m·k), and the electromagnetic interference shielding (EMI SE) reached 34.9 dB at X-band region, meaning 99.97 % shielding efficiency to EWMs energy. Thereafter, by tapping into the manufacturing potential of 3D printing, a series of ideal parts featuring arbitrarily designated structures and exceptional performance was constructed. Particularly, the 3D-printed heat sinks possessed outstanding behaviors in thermal management, where the corresponding initial dissipating rate achieved a 266 % improvement over that of the pure one. Besides, the 3D-printed shielding module posed high-efficiency EMI SE performance, corresponding to 35.8 dB at a specific Bluetooth-interaction signal (2.4 GHz). Overall, this innovative study not only enriches the printable materials with tailored multifunctionality but also brings the promising potential for applications in the next-generation functional parts.

Sistem Pemadam Kebakaran Otomatis Berkonsep Smarthouse

Home fire disasters are still common around us. This problem is a challenge in order to be able to find a solution. One solution to secure a home from a potential fire is to apply smarthome technology. Based on this problem, the idea arose to make an automatic fire extinguisher that can spray water with a water pump when it detects smoke (CO) due to a fire and circulates air in the room with an exhaust fan when an LPG gas cylinder leak is detected in the house so as to prevent a house fire. This tool is planned to be connected to the GSM module so that wherever we are we can find out if there is a fire in our home. This tool is made by utilizing the Smoke Gas Sensor (MQ 2), Temperature Sensor (LM35), Arduino Uno, GSM SIM 900 Module, Relay, Buzer, Exhaust Fan and Water Pump as its main components. Arduino Uno is used as the controller of this machine. The GSM SIM 900 Shield module is used for connection via SMS as a remote notification notification, LM35 as a temperature detector, and MQ 2 as a butane gas detector when there is a leak of LPG gas cylinders and fire smoke (CO) when a fire occurs. This tool can extinguish fires using a water pump from the detection of smoke (CO) and temperatures when more than 500 ppm and 40oC and circulate air using an exhaust fan with additional safety features when there is an LPG gas leak when gas is detected 500 ppm and send it with notification notification via SMS using the GSM SIM 900 module Shield. The measured voltage of the MQ2 sensor when clean air reaches 189.3 mV and the percent error of the LM35 reaches 0.88423%.

Progress in ITER ECE diagnostic design and integration

The ITER electron cyclotron emission (ECE) diagnostic system has primary roles in providing measurements of the core electron temperature profile and the electron temperature fluctuation associated with the neoclassical tearing modes. The ITER ECE system includes a radial and oblique line-of-sight. Four 43-meter long low-loss transmission lines (TLs) are designed to transmit millimeter wave power in the frequency range of 70–1000 GHz in both X- and O-mode polarization from the port plug to the ECE instrumentation room in the diagnostic building. The measurement instrumentation includes two Fourier transform spectrometer (FTS) systems and two radiometer systems. The Indian Domestic Agency (IN-DA) and United States Domestic Agency share the responsibility. The IN-DA scope excluding instrumentation and control has passed its preliminary design review and is progressing towards the final design review (FDR). In parallel, the diagnostic integration in different areas is ongoing. Several captive components for the TLs have passed FDR and will be manufactured for installation in the tokamak building soon. A peer review meeting has been held on the prototype hot calibration source, and its integration and new thermal analysis in the diagnostic shield module are continuing. A prototype TL is being tested. A prototype polarizing Martin-Puplett type FTS, operating in the frequency range 70–1000 GHz, features an in-vacuo fast scanning mechanism and a cryo-cooled dual-channel THz detector system. Its performance has been assessed in detail against ITER requirements.

Defending Person Detection Against Adversarial Patch Attack by Using Universal Defensive Frame

Person detection has attracted great attention in the computer vision area and is an imperative element in human-centric computer vision. Although the predictive performances of person detection networks have been improved dramatically, they are vulnerable to adversarial patch attacks. Changing the pixels in a restricted region can easily fool the person detection network in safety-critical applications such as autonomous driving and security systems. Despite the necessity of countering adversarial patch attacks, very few efforts have been dedicated to defending person detection against adversarial patch attack. In this paper, we propose a novel defense strategy that defends against an adversarial patch attack by optimizing a defensive frame for person detection. The defensive frame alleviates the effect of the adversarial patch while maintaining person detection performance with clean person. The proposed defensive frame in the person detection is generated with a competitive learning algorithm which makes an iterative competition between detection threatening module and detection shielding module in person detection. Comprehensive experimental results demonstrate that the proposed method effectively defends person detection against adversarial patch attacks.

A novel method for rapid calculation of moderated neutron spectrum and its application in deep penetration

The moderated neutron spectrum has an essential influence on the neutronics experimental studies and the neutron transport simulation method (such as Monte Carlo method) is one of the important methods for the calculation of it. The Monte Carlo method is characterized by its high accuracy, however, it will bring high time-consuming problems, and it is difficult to converge in the case of deep penetration. In this research, a novel method for rapid calculation of moderated neutron spectrum was developed. It used the Monte Carlo method to decompose typical shielding materials into a library according to a fixed thickness and calculated the multi-dimensional response matrix corresponding to the shielding module. With adjustment of its thickness, the moderated neutron spectrum was able to be calculated through matrix operation. The proposed method was verified under the moderator composed of shielding modules of different numbers, thickness and materials by comparing with the results of the Monte Carlo algorithm. The results stated the moderated neutron spectrum calculated by this method and Monte Carlo algorithm reached the order of 1.000E−06 on the MSE. Furthermore, the proposed method was verified with a simplified thermal reactor TRIGA in the case of deep penetration. The results showed that the moderated neutron spectrum in the convergent energy range of the two methods also performed well, and in the non-convergent energy range, the proposed method could give a heuristic neutron spectrum.

Development of UAV-Based PM2.5 Monitoring System

This paper proposes a UAV-based PM2.5 air quality and temperature-humidity monitoring system. The system includes an air quality detector comprising four Arduino sensor modules. Specifically, it includes a dust (DSM501A) sensor and a temperature and humidity (DHT11) sensor. The NEO-6M GPS module and DS3231 real-time module are also included for input visualization. A DIY SD card logging shield and memory module is also available for data recording purposes. The Arduino-based board houses multiple sensors and all are programmable using the Arduino integrated development environment (IDE) coding tool. Measurements conducted in a vertical flight path show promise where comparisons with ground truth references data showed good similarity. Overall, the results point to the idea that a light-weight and portable system can be used for accurate and reliable remote sensing data collection (in this case, PM2.5 concentration data and environmental data).

Microcontroller Based Money Storing Tools with Web Monitoring and Social Media

The money deposit box is one of the equipment at home that functions as a place to store money, although there are many practical money storage media, but there are still those who like to store money in the Money Deposit Box but in that storage many do not know how much the nominal money is. already saved. For this reason, a money storage box based on the Arduino Mega microcontroller was made. This tool can provide information on the amount of money saved and is equipped with a lock as a security. This study designs the hardware platform: (1) Ardunio Mega 2560 (2) TCS3200 sensor (3) DC motor (4) LCD i2C (5) 1ch relay (6) selenoyd doorlock (7) RTC DS3231 (8) Ethernet shield module, and Software: (1)Windows 10 (2)Arduino IDE 1.8 (2)XAMPP 3.2 (3)PHP 10 (4)MySQL (5)Visual Studio Code 1.5 The system is connected to the Internet Network. the data flow will be stored into a MySQL-based database at the NCC Lab, the nominal money obtained from reading the TCS3200 will be flowed through the Internet network, where the use of the ethernet shield module can integrate money storage equipment on the computer with a local MySQL database. Integration of hardware components, software and internet network.

Modeling of the stress-strain state of ITER upper ports №2 & №8 constructions’ components under thermal, electromagnetic and inertial loads

This paper presents the results of calculations of the upper port plug (UPP) of the ITER upper ports №2 and №8. Detailed finite-element models of the UPP structure were developed taking into account nonlinear contact interaction between the diagnostic shield module with extension frame and the UPP structure. In the structural analysis under design loads the stress-strain state (SSS) taking into account bolts pretension was obtained. Besides, the FE model includes cooling system pipes and boron carbide shielding. In the thermal analysis of the UPP for baking and normal operation modes the neutron analysis data was taken into account. The UPP cooling systems’ hydrodynamic characteristics were calculated including the flow-pressure characteristics. Subsequently, the whole UPP construction flow and pressure characteristics were evaluated taking into account the presence of throttling devices in the UPP hydraulic circuit. Structural analysis of the UPPS during seismic and electromagnetic events was carried out using the response spectrum method based on the response spectra at the UP point of the ITER building and interface electromagnetic loads due to the vacuum vessel movements respectively. The FE model includes port extension from the generic upper port plug model. Except this, the response spectra at the tenant attachment points were calculated using power spectral density analysis. Laplace force distribution in the UPP under different scenarios of plasma disruption was calculated. The electromagnetic model was significantly refined and includes the extension frame trays. Based on the electromagnetic analysis data, the structural analysis of the UPP under electromagnetic loads was carried out.

Advanced design of the ITER core CXRS shutter and integration into the diagnostic shield module of the Upper Port Plug No. 3

For the ITER core CXRS diagnostic, a shutter is mandatory to protect the first mirror when no measurement takes place. With the continuing design development of the diagnostic and the knowledge obtained from previous shutter prototypes, the frictionless fast shutter did undergo some design changes and manufacturing improvements without degrading the performance (opening/closing <1 s). In this paper, the major modifications of the shutter design are presented. An adjustment system was developed to allow compensation of manufacturing deviations and precise positioning of the protective blade according to the final aperture position, which is not known before the final assembly with the as-built dimensions of the port plug and diagnostic shield module (DSM). The shutter components and their adjustment systems are implemented into the shutter‘s actively cooled base structure, which in turn simplifies the remote handling procedure. For the helium circuit an activity study is presented, which allows to access the nuclear pressure equipment classification and to determine the number of required purges during the ITER lifetime. With the heat loads obtained from the known heat flow on the blade and from the neutronics analysis, a thermal FE-analysis was performed on the full shutter model by which the expected heat flow at the mechanical interfaces can be given.

Fatigue behavior testing and evaluation of ITER In-vessel mock-up coil under combined thermal and electromagnetic loads

ITER In-vessel coils (IVCs) are the components to be installed in the vacuum vessel for plasma positions compensation controlling. Every coil will be wound continuously and clamped through the welded Inconel 625 brackets. The coils are planned to be bolted to the rails which are welded to the vacuum vessel wall behind the blanket shield modules. The operation condition is severe for the IVC coils, combined with high radiation, high temperature, as well as the high thermal and electromagnetic loads. To make sure the safe operation, tests have been done on the mock-up coil to check its fatigue properties under the combined thermal and mechanical loads before the finalization of the design. The integrity of the mock-up coil has been evaluated after the fatigue cycling tests. In this paper, the details are presented on the test procedures and the measurement results are summarized.