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At least 289 records · Page 16
All sourcesNASA NTRSDOE OSTI
DOE OSTI2017

Design and implementation of HuREX analysis supporting interface - 171

Human error is recognized as one of the main causes to affect to the socio-technical system including nuclear power plant. Therefore, reducing human error through human reliability analysis (HRA) is a critical issue. Moreover, sufficient and reliable human performance data collection is a prerequisite for ensuring the safety of nuclear power plants. Korea Atomic Energy Research Institute developed the HuREX (Human Reliability data Extraction) framework to collect and analyze the responses of human operators from simulator training records of nuclear power plant. Thus, the development and computer software interfaces of the database are essential to efficiently support human reliability analysis. In this study, OPERA database was developed in accordance with the following process. First, the essential data required for the HRA analysis (e.g., plant data, procedures, system and equipment info, operating crews, results of simulator experiments, and so forth) was stored in the database. In addition, standardized procedures and related items were stored in the database to support HRA quantification. A data structure was developed to store crew responses conducted by operators to cope with an emergency situation during simulator experiments. In addition, various interfaces that escalate efficiency of the HuREX applications were developed. The HuREX analysis support interface was developed with HuREX Video Analyzer for observation of simulator collection data (e.g., audio-visual records, plant parameters, operator's action logs) and HuREX Data Analyzer for analysis of operator's conducted task. By using the OPERA database and HuREX analysis support interface developed through this research, maximizing the efficiency of human reliability analysis based on simulator training data. (authors)

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
DOE OSTI2017

Enhancing power plant safety through simulated cyber events - 341

There are gaps in understanding how a cyber-attack would manifest itself within power plants and what these events would look like within the control room from an operator's perspective. This is especially true for nuclear power plants where safety has much broader consequences than nonnuclear plants. The operating and emergency procedures that operators currently use are likely inadequate for targeted cyber-attacks. This research focuses on understanding how a cyber event would affect the operation of the plant, how an operator would perceive the event, and if the operator's actions would keep the plant in a safe condition. This research is part of Sandia's Laboratory Directed Research and Development program where a nuclear power plant cyber model of the control system digital architecture is coupled with a generic pressurized water reactor plant training simulator. Cyber event scenarios will be performed on the coupled system with plant operators. The scenarios simulate plant conditions that may exist during a cyber-attack, component failure, or insider sabotage, and provide an understanding of the displayed information and the actual plant conditions. These scenarios will determine if plant operators can 1) recognize that they are under cyber-attack and 2) take appropriate actions to keep the plant safe. This will also provide the opportunity to assess the operator cognitive workload during such events and identify where improvements might be made. Experiments with nuclear power plant operators will be carried out over FY 2018 and results of the research are expected by the end of FY 2018. (authors)

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
DOE OSTI2016

An Approach for Assessing Consequences of Potential Supply Chain and Insider Contributed Cyber Attacks on Nuclear Power Plants

The Stuxnet attack at the Natanz facility is an example of a targeted and successful cyber attack on a nuclear facility. Snowden's release of National Security Agency documents demonstrated the consequences of the insider threat. More recently, the United States tried to attack North Korea but failed, South Korea was attempting to attack North Korea, and both applied Stuxnet-like approaches. These sophisticated targeted attacks differ from web-site hacking events that are reported almost daily in the news mainly because targeted attacks require detailed design and operation information of the systems attacked and/or are often carried out by insiders. For instance, in order to minimize disruption of facilities around the world, Stuxnet remained idle until it recognized the specific configuration of the Natanz facility, demonstrating that the attackers possessed extremely detailed information about the facility. Such targeted cyber attacks could become a national-level military weapon and be used in coercion of hostile countries. While U.S. nuclear power plants (NPPs) are well designed and protected and not easily attacked through internet hacking, there have been a few digital-system-related incidents. For example, in 2003, the Slammer worm breached the private network of the Davis Besse plant and disabled a safety monitoring system for almost five hours. The breach did not pose a safety hazard because the plant was offline, but it demonstrates the vulnerability of NPP systems. The worm did not enter the plant systems directly; it began by entering the systems of a Davis Besse contractor, and entered through the T1 line bridging the contractor's computer and Davis Besse's corporate networks. The T1 line was not protected by the plant's firewall. The success of the Stuxnet-Natanz case demonstrates that supply-chain level attack (i.e., physically tampering with digital systems to install undetectable malware for the purpose of bringing harm to a player further down the supply chain network) plays a crucial role in a successful attack. Although attacking an NPP naturally requires more complex strategies and tactics than internet hacking, NPP's have a variety of sophisticated and possibly sensitive systems that may be attacked. Previous studies, for example, Baylon, have identified and confirmed that such attack strategies and tactics can be designed and could produce severe damage to an NPP. Current NPPs were designed according to design basis accidents that predate use of the internet by the general public and did not take into consideration potential cyber attacks that could be carried out by state-sponsored attackers and malicious insiders. To date, no detailed engineering analysis has been performed to realistically examine the consequences these attacks may have on the plants. In this paper, we discuss an approach for assessing the potential consequences of Stuxnet type of attacks. We will examine the engineering criteria used in designing the plants, develop possible attack scenarios in terms of the structures, components, and systems (SSCs) being controlled by digital systems at the NPPs, perform engineering analysis to determine if the attacks would impose conditions that are beyond design bases, and categorize the consequences of the potential accidents. (authors)

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
DOE OSTI2017

Assessment of dynamic PRA techniques with industry average component performance data - 208

In the nuclear industry, risk monitors are intended to provide a point-in-time estimate of the system risk given the current plant configuration. Current risk monitors are limited in that they do not properly take into account the deteriorating states of plant equipment, which are unit-specific. Current approaches to computing risk monitors use probabilistic risk assessment (PRA) techniques, but the assessment is typically a snapshot in time. Living PRA models attempt to address limitations of traditional PRA models in a limited sense by including temporary changes in plant and system configurations. However, information on plant component condition is not considered. This often leaves risk monitors using living PRA models incapable of conducting evaluations with dynamic degradation scenarios evolving over time. There is a need to develop enabling approaches to solidify risk monitors to provide time- and condition-dependent risk by integrating traditional PRA models with condition monitoring and prognostic techniques. This paper presents an estimation of system risk evolution over time by integrating plant risk monitoring data with dynamic PRA methods that incorporate aging and degradation. Several online, nondestructive approaches have been developed for diagnosing plant component conditions in the nuclear industry, i.e., using a condition indication index, vibration analysis, current signatures, and operational history . In this work, the component performance measures at U.S. commercial nuclear power plants are incorporated within the dynamic PRA methodologies to provide better estimates of the probability of failures. Aging and degradation are modeled within the Level 1 PRA framework, are applied to several failure modes of pumps, and can be extended to a range of components, namely, valves, generators, batteries, and pipes. (authors)

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
DOE OSTI2017

An overview of the IEEE human factors standard development activities - 2017 - 230

Since 1980 the Institute of Electrical and Electronics Engineers (IEEE) has supported development of human factors (HF) standards. Within IEEE, Subcommittee 5 (SC5) of the Nuclear Power Engineering Committee develops and maintains HF standards applicable to nuclear facilities. These standards are structured in a hierarchical fashion. The top-level standard defines the HF tasks required to support the integration of human performance into the design process. Five lower tier documents expand upon the upper tier standard. Presently, two new HF standards projects are underway; one to provide HF guidance for the validation of the system interface design and integrated systems operation and another for designing and developing computer-based displays for monitoring and control of nuclear facilities. In addition to producing and maintaining HF standards, SC5 is also involved in outreach activities, including sponsorship of a series of conferences on human factors and nuclear power plants. (authors)

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
DOE OSTI2017

Risk informed cyber security for nuclear power plants - 342

Nuclear power plants are increasingly adding digital components for plant operation, safety, and security. These digital components fill a gap with legacy equipment where replacement components no longer exist. They also benefit operation of the plant by increasing efficiency in power generation, monitoring of equipment and plant parameters, as well as aiding operator control. However, the addition of digital components and systems also adds cyber risks with previously unanalyzed failure modes and attack vectors are introduced with these new systems. These risks are difficult to identify, analyze, and mitigate due to the increasingly complex nature of the digital components and the integration of these components with additional plant processes and communication networks. The research presented in this paper develops a new method that addresses the cyber risk to inform appropriate levels of protection. EPRI and Sandia are working under a Cooperative Research and Development Agreement to develop an effective method of evaluating the cyber risk in production nuclear power facilities. The Cyber Hazards Analysis Risk Methodology (CHARM) focuses on ensuring adequate controls are in place for appropriate cyber protection of the plant from radiological release or generation risk. Existing plant hazards analyses (e.g., PRA, FTA) do not account for software deficiencies or adversarial intent. This method leverages existing plant analyses and MIT's Systems Theoretic Process Analysis (STPA) to create cyber informed fault trees. These new fault trees will provide the basis for comprehensive cyber risk analysis and help ensure potential gaps in cyber security controls are identified and corrected. (authors)

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
DOE OSTI2015

KGK-2-type detector of gamma-radiation power for diagnosis of nuclear reactor radiation fields within the range from 1 µGy/s to 100 Gy/s

The construction of the KGK-2-type detector of γ-radiation power is briefly described. The diagnostic possibilities of the detector are shown by the example of results of the dose rate measurement in the energy start-ups of the BR-K1 and BR-1M reactors implemented in the mode of generating fission pulses on delayed neutrons. The possibilities of using the KGK-2 detector for postpulse γ diagnostics are demonstrated by the example of results of measurements in the fission pulse on prompt neutrons of the BR-1M reactor.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
DOE OSTI2017

Implementation of wireless technologies in nuclear power plants' electromagnetic environment using cognitive radio system - 153

Wireless technologies have increased efficiency in many industrial settings across the world by enabling a mobile workforce and improving communications. Unfortunately, the nuclear power industry has been slow to adopt wireless technology as a result of safety, security, and reliability concerns expressed by regulators and others. A Research and Development (R and D) effort is currently being conducted to address two significant technical concerns for the introduction of wireless technology in nuclear power plants, which are electromagnetic compatibility (EMC) and wireless coexistence. Most equipment in nuclear power plants has never been tested for vulnerability to wireless transmission. As such, the impact of modern wireless devices on nuclear safety and plant reliability is not understood. Existing guidance from the Nuclear Regulatory Commission (NRC) and Electric Power Research Institute (EPRI) rely on the use of exclusion zones to protect plant equipment, which can result in exclusion zones of up to eight feet for some tablet devices rendering them ineffective for the mobile workforce. Another unknown is how different wireless devices will operate in close proximity to one another in the harsh electromagnetic environment of a nuclear power plant. These issues are being addressed through development of a cognitive radio system that has the ability to generate and output multiple wireless signals such as Wi-Fi, Bluetooth, and cellular communications at varying power levels and frequencies. The cognitive radio system is a modular system that can test nuclear plant equipment located in training areas, simulators, and the actual plant environment. In addition to using the system for testing plant equipment to wireless signals and EMC standards, the system can also monitor the radio spectrum for usage in other plant focuses such as cyber security. The R and D work will provide the objective guidance for the nuclear industry in the two areas mentioned and will develop a cognitive radio system for in-plant EMC and coexistence testing. The system will assist in the seamless use of wireless technology in nuclear power plants while greatly reducing the risks wireless signals may introduce. (authors)

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
DOE OSTI2017

Computerized operator support system and human performance in the control room - 262

An operator aid technology to assist nuclear plant operators maintain situation awareness and detect faults earlier than would be possible using conventional control room technologies is described. Coined the Computerized Operator Support System (COSS), this technology is aimed at the human-machine interface. The COSS has been implemented as a prototype system operating in the control room environment of a full-scale simulator for a commercial nuclear power plant. A human factors assessment that involved two licensed reactor crews was performed to evaluate crew performance. This paper describes the development of the COSS, the underlying fault-detection architecture, and feedback received based on operator-in-the-loop studies. (authors)

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
DOE OSTI2017

Continuous measurement of boron concentration in nuclear power plants: why is it essential for safe and efficient operation? - 318

As a neutron-absorber, Boron 10 plays a significant role in nuclear power plants as it is used in order to control reactivity in the core, together with control rods. For that reason; it is a key parameter that has to be controlled. In a similar way, it is crucial to be able to detect a boron dilution in the primary circuit, as it would causes severe damages if not detected and controlled. Thus, it comes as evidence that a boron concentration monitoring system is a key for every nuclear power plant. Consequently, it becomes important to provide plant operators with a boron concentration measurement issued by a reliable, redundant, classified and qualified system, with high accuracy and short response time. In order to cover this need, Rolls-Royce has designed Boronline{sup R}, the latest generation of boron meter, which provides nuclear power plant operators with a permanent record of boron concentration of primary circuit by way of continuous sampling and real-time measurements. Boronline takes part of a new generation of Advanced Sensors and Measurements Technologies. In this paper, boron meter role, main functions and measuring principles will be detailed, as well as technical characteristics of the new generation of boron meter will be presented. (authors)

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
DOE OSTI2018

Robotics for Nuclear Monitoring and Inspection - 18029

As a greater number of the world's nuclear facilities approach the end of their planned lifetime and enter the decommissioning and dismantling phase, a greater impetus than ever is being placed on the use of novel technologies to assist in this otherwise extremely lengthy, complicated and costly process. Being host to numerous first-generation plants, as well as the Sellafield Limited nuclear reprocessing facility, the UK is now requiring the use of a range of robotic systems and is well-placed to act as a test-bed for the deployment of these platforms. Presented in this work is the overview of the wide range of robotic research that is occurring at the University of Bristol. Not limited to ground-based platforms - those developed at the University Bristol,UK, include; airborne, underwater as well as pipeline network monitoring systems. Through the application of each of these robotic systems, not only is the dose-rate otherwise experienced by the operator removed, but the costs associated with the work are also significantly reduced, as well as the speed at which it is performed dramatically increased. All the systems descried in this work have been successfully deployed at one (or multiple) nuclear sites, with the results used to inform further decommissioning - typically within environments previously uncharacterised due either to their inaccessibility or high levels of radioactivity. (authors)

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
DOE OSTI2017

Ontology to guide scenario design to evaluate new technologies for control room modernization - 127

Modernization of nuclear power plants (NPPs) are introducing new human-system interface (HSI) technology that may have unanticipated impact on control room operations. Introduction of HSI thus requires careful evaluation and integrated system validation involving human-in-the-loop experiments with high-fidelity simulation and realistic scenarios. To support the technology evaluation in modernization of NPPs, this paper reports our research on constructing an 'scenario development ontology' for the nuclear industry. We conducted a literature review to produce a preliminary flow chart of the scenario development process and verified the flow chart through interviews with ten domain professionals. The interviews confirmed the key steps in the process flow chart and provided a compendium of approximately 100 scenario attributes, which were divided according to their relevance to HSI evaluation. The next step will be to conduct additional interviews to expand and generalize the ontology that can facilitate vendor and industry evaluation of current and future control room modernization projects. This ontology is particularly intended to facilitate vendor and industry evaluation of current and future control room modernization projects. (authors)

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
DOE OSTI2017

Development of NUREG-0700, rev 3 - 229

The U.S. Nuclear Regulatory Commission (NRC) evaluates the human factors engineering (HFE) of nuclear power plant design and operations to protect public health and safety. The HFE safety reviews encompass both the design process and its products. Detailed guidance for these reviews is provided in two key documents: the HFE Program Review Model (NUREG-0711) and the Human-System Interface Design Review Guidelines (NUREG-0700). The NRC is committed to the periodic update and improvement of the guidance to ensure that they remain state-of-the-art design evaluation tools. In this paper, we will describe the updates made to NUREG-0700 that resulted in Revision 3 of the guidance. (authors)

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
DOE OSTI2017

Application of eye tracking for measurement and evaluation in human factors studies in control room modernization - 309

An important element of human factors engineering (HFE) pertains to measurement and evaluation (M and E). The role of HFE-M and E should be integrated throughout the entire control room modernization (CRM) process and be used for human-system performance evaluation and diagnostic purposes with resolving potential human engineering deficiencies (HEDs) and other human machine interface (HMI) design issues. NUREG-0711 describes how HFE in CRM should employ a hierarchical set of measures, particularly during integrated system validation (ISV), including plant performance, personnel task performance, situation awareness, cognitive workload, and anthropometric/ physiological factors. Historically, subjective measures have been primarily used since they are easier to collect and do not require specialized equipment. However, there are pitfalls with relying solely on subjective measures in M and E such that negatively impact reliability, sensitivity, and objectivity. As part of comprehensively capturing a diverse set of measures that strengthen findings and inferences made of the benefits from emerging technologies like advanced displays, this paper discusses the value of using eye tracking as an objective method that can be used in M and E. A brief description of eye tracking technology and relevant eye tracking measures is provided. Additionally, technical considerations and the unique challenges with using eye tracking in full-scaled simulations are addressed. Finally, this paper shares preliminary findings regarding the use of a wearable eye tracking system in a full-scale simulator study. These findings should help guide future full-scale simulator studies using eye tracking as a methodology to evaluate human-system performance. (authors)

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
DOE OSTI2017

Training and certification of human organizational factors designers in nuclear plant engineering - 344

Performing an increasing number of small and large-scope nuclear Human Factors Programs, AREVA NP is facing the challenging situation that (1) well-trained experts in Human Factors or Usability Engineering are currently hard to find and (2) newly hired ones need at least two years 'on the job' to become familiar with the nuclear field and the complexity of engineering Human Factors in this field. To innovatively meet this challenge we focus instead on company-internal engineers. Demonstrated nuclear engineering knowledge and skills and pronounced interest to extend both renders them optimal applicants to the AREVA NP two years Human Organizational Factors Training and Certification program. The AREVA NP training shall convey Human Factors knowledge and skills within the limited time of two years. We also stress the need to change participants' mindset from a technically-biased to a human-centered approach, committed to involve end-users throughout design. Next to psychology principles, user testing, user-centered design, plant operation principles, and the acquisition and documentation of users' requirements, design constraints, and inherent tradeoffs, participants will be trained to apply learned methods in a real environment and meet the challenges of real projects. The following sections provide insights in the training conception and preparation phase, the identification of appropriate candidates, the development of course syllabuses, and the schedule of lectures and tests. The promising experiences made thus far are reported as well. (authors)

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
DOE OSTI2025

Modular Processing of Flare Gas for Carbon Nanoproducts

This project demonstrated the technical viability and economic promise of a modular system for converting flared natural gas into valuable carbon nanoproducts (CNPs) through catalytic chemical vapor deposition (CVD). All major project milestones were successfully completed, including reactor design and commissioning, catalyst development, process optimization, technoeconomic analysis, and application testing in concrete systems. The overarching goal was to create a scalable, field-deployable process that valorizes stranded methane by producing high-value carbon materials for use in cementitious composites. At the lab scale, the team designed and built a fluidized bed reactor optimized for use with silica fume-supported nickel catalysts synthesized via atomic layer deposition (ALD). A statistically designed sintering study enabled precise tuning of nickel nanoparticle size, identifying the influence of oxygen partial pressure, time, and temperature on catalyst morphology and performance. These insights allowed the team to target catalyst conditions that maximize carbon nanofilament growth. Subsequent CVD experiments achieved up to 31.8 wt% carbon deposition under optimized conditions, with TEM confirming the presence of nanofilament structures and sustained hydrogen evolution during reaction. Reactor upgrades and empirical fluidization studies supported the development of reliable, repeatable experimental protocols. The modular pilot-scale skid reactor was fully constructed, instrumented, and commissioned. Capable of operating at 675–800°C and pressures up to 290 psig, the system was designed for continuous operation at a carbon production rate of 1 kg/hr. Initial demonstration runs confirmed solids handling, thermal control, and system leak-tightness, although a critical reactor component (the downfeed tube) was inadvertently omitted during final assembly. This omission limited gas–solid contact and prevented meaningful carbon deposition during pilot-scale CVD runs. Nonetheless, the system operated safely under design conditions, and the root cause of performance limitations was clearly identified. Complementary work on UHPC formulations demonstrated that small additions of carbon nanoproducts, including those derived from flare gas, can significantly enhance mechanical performance while preserving workability. A comprehensive study of CNF dispersion techniques and mix design optimization led to a clear protocol for integrating these nanomaterials into concrete. Incorporation of CNPs improved flexural toughness and reduced porosity, supporting their use in high-performance infrastructure applications. A technoeconomic analysis (TEA) confirmed that this process can produce CNP-loaded catalyst material at a levelized cost below $\$$7/kg across a range of catalyst loadings and reaction yields. With estimated market values for the carbon composite product ranging from $\$$14 to over $\$$60/kg, and the ability to blend CNPs into concrete at sub-percent levels with less than 10% added cost, the system presents a compelling economic case. While additional engineering work is needed to optimize fluidization and heat transfer at scale, this project establishes a strong foundation for commercial development. The process is not only technically sound but also economically promising, representing a viable pathway for flare gas mitigation through modular carbon nanomaterial production.

03 NATURAL GAS↗
DOE OSTI2022

Operational Resilience of Nuclear-Renewable Integrated-Energy Microgrids

The increasing prevalence and severity of wildfires, severe storms, and cyberattacks is driving the introduction of numerous microgrids to improve resilience locally. While distributed energy resources (DERs), such as small-scale wind and solar photovoltaics with storage, will be major components in future microgrids, today, the majority of microgrids are backed up with fossil-fuel-based generators. Small modular reactors (SMRs) can form synergistic mix with DERs due to their ability to provide baseload and flexible power. The heat produced by SMRs can also fulfill the heating needs of microgrid consumers. This paper discusses an operational scheme based on distributed control of flexible power assets to strengthen the operational resilience of SMR-DER integrated-energy microgrids. A framework is developed to assess the operational resilience of SMR-DER microgrids in terms of system adaptive real-power capacity quantified as a response area metric (RAM). Month-long simulation results are shown with a microgrid developed in a modified Institute of Electrical and Electronics Engineers (IEEE)-30 bus system. The RAM values calculated along the operational simulation reflect the system resilience in real time and can be used to supervise the microgrid operation and reactor’s autonomous control.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
DOE OSTI2017

Operating displays - new concept: high performance displays - 118

New control rooms in Nuclear Power Plants using digital Distributed Control System (DCS) operated with software displays, are providing thousands of signals to the operating crew. When an event happens, the Flood of information provided to operators could obscure the initiator event increasing the operator response time, work load and complicating the selection of the actions to be performed. There are some initiatives that are trying to minimize the 'avalanche effect' as the alarm engineering filtering and prioritization or diagnostic displays. Likewise, new control rooms are lost the availability to know the plant status just with a quick glance to the panel indicators. Regarding Small Modular Reactors, where in some cases four operators should monitor and control twelve reactors, these problems are even more significant. The challenge is to find a solution, based on current digital systems, that supply information to operators in order to prevent events and take early actions to minimize or avoid any unexpected incident. In order to minimize human errors, Tecnatom has developed a specific set of displays, called 'High Performance Displays' (HPD) based on objectives, work environment limitation, and non-anticipated events. These displays are being design following the HFE standards: applying the NUREG-0711 elements to identify the information that they have to content and the NUREG-0700 to design the interface. The function of these displays is monitoring the plant situation in a way that the operators are able to recognize any potential event at a simple glance but controlling thousands of signals through pattern recognition, symmetries, regular polygons and colors. The objective of the HPD is to provide an integrated function minimizing the tunnel effect and reduce the workload during the diagnosis phase. Moreover, HPD enhance operators to take the right actions to anticipate the response to any event, even avoiding it, if possible This paper analyzes how HPD's have been design as well as presents the results of a preliminary validation of their capabilities. The preliminary validation is a reduce validation in a full scope simulator running two representative scenarios of abnormal and emergency operation. The analysis is focused on the first stage of the event, i.e. the detection phase, HPD's have been installed in a generic full scope simulator of a nuclear power plant, digital controlled. Both scenarios have been performed by two different operator crews. The first operator shift has worked with the conventional human machine interface, that is, displays similar to the ones currently installed in existing nuclear power plant with digital control. The second crew, reproduce the same scenarios but with HPD available. The studio collects preliminary data in order to compare results, draw lesson learned from the experience to improve HPD design, and find solutions in terms of reducing human errors, human workload, and increase the availability of the plant. (authors)

22 GENERAL STUDIES OF NUCLEAR REACTORS↗