Support Capability Research Articles

Universal Virtual Synchronous Generator Based on Extended Virtual Inertia to Enhance Power and Frequency Response

Virtual synchronous generators (VSG) are considered a new generation of grid-friendly inverters with the same inertial support characteristics as synchronous generators (SG). However, the inertia support comes with the side effects of power and frequency response deterioration. The existing VSG power oscillation suppression methods have limitations such as complex controller parameter tuning, altering the frequency support characteristics, and power quality degradation. To address these issues, this paper proposes a universal VSG control strategy based on extended virtual inertia (VSG-EVI). Herein, the virtual inertia is no longer a constant or varying number; it is endowed with frequency domain characteristics to improve the VSG transient responses. Moreover, a detailed parameter design process is given in detail. Compared with the conventional VSG (CVSG), VSG-EVI significantly suppress the power and frequency oscillations. Compared with the existing VSG oscillation suppression methods, VSG-EVI addresses the issues of the reduction of frequency support capability, whereas the controller parametric design process is simplified with the proposed intuitive extended virtual inertia. Finally, the proposed VSG-EVI method is thoroughly validated by experiments under both grid-connected and stand-alone modes.

ASPECTS OF MANAGEMENT OF MEDICAL AND EVACUATION SUPPORT FOR THE TROOPS IN THE CONDITIONS OF THE UNIFIED MEDICAL SPACE OF UKRAINE

The article focuses on the need for the integration of civil and military medical institutions into the unified medical space of Ukraine. It substantiates the development of a holistic system of medical and evacuation support for the troops in combination with the resource capabilities of the civil health care system. It also defines the necessary prerequisites for the development of such a system, namely unity of views on the organization, tactics and procedure for the use of forces and means of medical services, and the capacity of civilian health care facilities for medical and evacuation support of military personnel. The Article describes specific management approaches regarding the medical and evacuation support capabilities of the Armed Forces of Ukraine (AFU) that will contribute to the implementation of efficient medical and evacuation measures and adequate support as well as measures for the medical protection of military personnel, etc. It also proves the importance of defining and clearly demarcating levels of medical care and required resources and considers the possibility of working out interdepartmental civil and military cooperation as well as refining the system of medical and evacuation support for servicemen of the Armed Forces of Ukraine in the conditions of the unified medical space of Ukraine.

Possibilities of Developing Medical Support Capabilities in the Area of Chemical, Biological Radiological and Nuclear Defence

The article deals with the evaluation of current possibilities of medical support capabilities in the area of Chemical, Biological, Radiological and Nuclear Defence. The evaluation of national strategic documents shows that the area of providing care in the event of chemical and biological hazards is significantly more developed than in the area of radiation, while the security threats associated with radiation are constantly growing. Analysis of NATO standardization documents in the field of medical support and relevant Czech doctrinal documents was carried out, based on which the diagnostics and triage of irradiated persons, called biological dosimetry, was identified as a potential capability. Using the capability planning methodology and based on the evaluation of the functional areas, a conceptual approach to the development of biological dosimetry capabilities was defined. The presented recommendations also include a proposal for the organizational structure of the Czech Armed Forces biodosimetric network.

Operational Reliability Assessment of Distribution Network With Energy Storage Systems

In this article, a novel approach that considers the time-varying load restoration capability is proposed for operational reliability assessment of distribution networks. To evaluate the operational reliability, two indices are firstly defined as the minimal load loss under the worst-case fault contingency in the upcoming time interval. To search for the optimal remedial actions for load restoration, a sequential network reconfiguration (NR) model is then proposed considering the reconfigurability of feeders and capability of emergent power support of energy storage systems (ESSs). Since this model is a complex nonlinear mixed integer programming model, an improved greedy searching-based algorithm is proposed to compute the optimal remedial actions and to further evaluate the risk of load loss. Comparative case studies are presented in this article to demonstrate that the load level, the expectation of the state-of-charge of ESS and the failure duration have the impacts on the system operational reliability. Besides, the proposed sequential NR model can be used to enhance the reliability of distribution networks by enabling an effective sequential load transfer strategy under emergent conditions. Unlike traditional reliability assessment, the proposed method provides the operators with the real-time awareness of the operational reliability level considering the real-time condition of distributed resource equipped feeders and worst-case emergency constraints.

A Study of Technological Capability in Selected Rice Processing Firms in Nigeria

In the advent of processing indigenous rice production, there is need to encourage local technology. This study simply provides an insight into the intertwining capabilities. Mainly, a snowballing primary data technique was used to gather data across the thirty-five licensed rice processing firms in the four geopolitical zones of country using structured questionnaire. Data gathered was then analysed using the descriptive statistics- mean. The results showed that on a Likert rating scale of 5, acquisition capability and production capability were rated above average while creative, supportive and adaptive capabilities were rated low. This indicates that the firms have sufficient capability in the area of acquisition of resources and conversion of technologies while the capability to provide training and improvement of technologies is low. The study concluded that rice processing operations in Nigeria could be enhanced if all technological capabilities are adequately developed. Keywords: Technological capability; rice processing; operations; development; industry DOI: 10.7176/IKM/13-3-02 Publication date: March 31 st 2023

Bottom-Up Support: Grid-Edge Technology [Editors’ Voice

The rise of a large number of technologies located at the edge of the grid (at the lowest voltage level of the distribution network) provides new bottom-up support capabilities for optimizing the operation of the distribution network and the transmission network.

Research on the Voltage Supporting Capability of Multi-VSC-HVDC Subsystems Operation Strategy to Receiving-end LCC-HVDC Network in Weak AC Grid

For the hybrid multi-infeed HVDC system in which the receiving-end grid is a strong AC grid including LCC-HVDC subsystems and multiple VSC-HVDC subsystems, it has higher voltage support capability. However, for weak AC grid, the voltage support capability of the multi-VSC-HVDC subsystems to the LCC-HVDC subsystem (voltage support capability-mVSCs-LCC) can resist the risk of commutation failure. Based on this consideration, this paper proposes an evaluation index called Dynamic Voltage Support Strength Factor (DVSF) for the hybrid multi-infeed system, and uses this index to qualitatively judge the voltage support capability-mVSCs-LCC in weak AC grid. In addition, the proposed evaluation index can also indirectly judge the ability of the LCC-HVDC subsystem to suppress commutation failure. Firstly, the mathematical model of the power flow of the LCC and VSC networks in the steady-state is analyzed, and the concept of DVSF applied to hybrid multi-infeed system is proposed. Furthermore, the DVSF index is also used to qualitatively judge the voltage support capability-mVSCs-LCC. Secondly, the influence of multiple VSC-HVDC subsystems with different operation strategies on the DVSF is analyzed with reference to the concept of DVSF. Finally, the indicators proposed in this paper are compared with other evaluation indicators through MATLAB simulation software to verify its effectiveness. More importantly, the effects of multi- VSC-HVDC subsystems using different coordinated control strategies on the voltage support capability of the receiving-end LCC-HVDC subsystem are also verified.

Role of Distributed Inverter-Based-Resources in Bulk Grid Primary Frequency Response Through HELICS Based SMTD Co-Simulation

In the recent years, there has been an increase in distributed inverter-based resources (D-IBRs) in the system that is impacting the grid performance. Dynamic transmission and distribution (T&D) co-simulation is an effective method to evaluate the impact of D-IBRs on the system response, however, implementation is a challenge. This article innovatively achieves accurate T&D model coordination with inclusion of dynamic models of power electronic controls. It also demonstrates that D-IBRs operating with grid-forming (GFM) controls with frequency support capability can aid in primary frequency regulation in a low-inertia power system. The article discusses the fundamentals of dynamic T&D co-simulation to analyze the primary frequency response on the IEEE 39-Bus transmission system coupled to IEEE 123-Bus distribution system with D-IBRs with GFM controls. To demonstrate scalability, a large system (286383 T&D buses) is co-simulated: IEEE 39-bus transmission system with all load buses coupled to a total of 2328 parallel IEEE 123-Bus distribution feeders containing a mix of D-IBRs is considered. The article also discusses the use of parallel computation used for distribution system solutions enabled in the scalable multi-timescale T&D co-simulation framework along with computation time comparisons between the large and small system simulations with GFM inverter dynamics.

Real-Time Estimation of Support Provision Capability for Poor-Observable Distribution Networks

An indispensable step towards coordinating the actions of distribution and transmission system operators ( <sc xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">dso</small> s- <sc xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">tso</small> ) is to estimate the range of flexibility that can be offered to the <sc xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">tso</small> by <sc xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">dso</small> s. Within this context, a data-driven probabilistic approach is proposed to evaluate the capability of a distribution network in providing active and reactive power support in real-time. To this end, in an offline phase, a linear discriminant analysis model, together with a piecewise linear model of the distribution network are trained to delineate the boundary of a region representing the adherence to distribution network operational constraints. In the implementation phase, this region comprises the feasible set of a series of optimization problems, formulated to determine the support provision capability. These optimization problems are of iterative linear programming type, which allows for real-time applicability. The evaluated support capability can be deemed as the available reserve in real-time transmission operation, which enables providing a coordinated response towards unexpected events, and facilitates the participation of distributed resources in the balancing market by granting an up-to-date estimation of available supports. This approach is tested on the IEEE 123-node system and verified through comparison with an AC optimal power flow technique.

Buckling and Wrinkling of Sandwich Structures Reinforced by Functionally Graded Carbon Nanotubes

Soft-core sandwich structures subjected to coplanar compression loading might exhibit wrinkling behaviors, which will reduce significantly the support capability of the structure. In order to prevent the wrinkling behaviors of sandwich structures, this work attempts to improve stiffness of face sheets reinforced by carbon nanotubes (CNTs). To achieve such a goal, the following work is to be required. First, an equivalent single-layer model will be proposed to accurately analyze the wrinkling behaviors of sandwich structures because only layerwise models possess the capability to accurately predict wrinkling behaviors of sandwich structures, but these models are often computationally expensive. Second, the influence of distributions of the CNTs through thickness on the buckling and wrinkling behaviors for the sandwich beams will be investigated in detail. Moreover, the translation mechanism between the buckling deformation and the wrinkling deformation has been also explored. The proposed model has been verified by using the quasi three-dimensional (3D) elasticity solutions and the 3D finite-element results (3D-FEM). Third, by selecting the proper distributions of the CNTs through the thickness of sandwich structures, the wrinkling behaviors of sandwich structures can be effectively prevented. Thus, a scheme resisting wrinkling deformation of sandwich structures has been proposed, which can provide a reference for other investigators.

영유아교사가 지각한 반성적 사고와 놀이지원 역량 및 놀이중심교육과정실천 역량 간 관계

영유아교사가 지각한 반성적 사고와 놀이지원 역량 및 놀이중심교육과정실천 역량 간 관계

Grid-Forming Converter Overcurrent Limiting Strategy Based on Additional Current Loop

Compared with current source converters, voltage source converters (grid-forming converters) have better frequency support capabilities, voltage support capabilities, and regulation performance, thus they have broad application prospects. However, the grid-forming (GFM) converter has insufficient current control ability, and it easily causes problems such as overcurrent issues when a fault occurs. Thus, this insufficiency is one of the most important challenges the GFM converter is faced with. Aiming to solve the problems mentioned above, this paper proposes a control method of a GFM converter achieved with a low-pass filter structure and an additional current loop. The additional current loop controls the dq-axis current components by acting on the outer loop to generate appropriate phase and voltage amplitude reference. The low-pass filter structure is used to solve the system frequency stability problem caused by the inclusion of the additional current loop. On the premise of ensuring that the system frequency meets the grid-connection requirements, the proposed strategy rapidly limits the output current within the allowable range and guarantees expected voltage source characteristics of the converter during the fault period. Finally, the effectiveness and superiority of the proposed control strategy are verified by MATLAB/Simulink simulations.

Development of a self-management support practice framework for addressing cancer-related fatigue: a modified Delphi study

PurposeManaging cancer-related fatigue requires individuals to adopt a range of self-management behaviours. However, clinicians report the lack of clear guidance on self-management support practices hinders their provision of supportive care. To develop consensus on a framework of core practices required by health professionals to deliver effective self-management support to cancer patients and survivors experiencing cancer-related fatigue.MethodsA preliminary framework of 47 practice items (14 Key Practices, 33 Practice Components) was derived from a systematic review, and a self-management support capability outline for primary care professionals. This preliminary framework was presented for consensus rating and comment in a two-round modified Delphi study conducted with a panel of health professionals, research academics, and cancer consumers.ResultsFifty-two panel participants comprising consumers (n = 25), health professionals (n = 19), and researchers (n = 16) were included in Round 1 of the modified Delphi study. Feedback from the panel produced consensus on retaining 27 of 47 original practice items without change. Seventeen items (including 12 modified, and 5 newly created practice items) were sent to the panel for rating in Round 2. Thirty-six experts produced consensus on retaining all 17 practice items in Round 2. The final framework comprised 44 items (13 Key Practices, 31 Practice Components).ConclusionsThe practice framework offers an evidence- and consensus-based model of best practice for health professionals providing self-management support for cancer-related fatigue.Implications for Cancer SurvivorsThis framework is the first to focus on quality provision of self-management support in managing cancer-related fatigue, one of the most prevalent symptoms experienced by cancer patients and survivors.

Business-to-business co-creation management practices for intellectual property value: Insights from Saudi Arabia

Managing intellectual property (IP) value appropriation remains a central challenge for business-to-business (B2B) networks due to B2B co-creation prospects for improved value-in-exchange and value-in-use for co-creation beneficiaries. This article aims to explore the management practices of B2B networks that enhance IP value from B2B co-creation. Using semi-structured interviews with sixteen IP management experts from the Kingdom of Saudi Arabia, the article proposes an integrated model of management strategies and guidelines for B2B co-creation with respect to IP value. The model posits that at the intra-organisational level, the main enabling processes for value appropriation are building communication skills, implementing hiring processes, and developing management systems for negotiations, talents, and intellectual assets, respectively. This level benefits from priorities placed on selecting strategic partners and fostering learning cultures for knowledge, technology, and venture co-creation processes. For the inter-organisational level, the proposed enabling processes are pursuing research funds and creating optimum designs for technology development and market positioning, respectively. Priorities at this level involve aligning complementary resources, developing clear agreements, and utilising supportive capabilities for technology and market co-creation.

Nonlinear model predictive control-based active power dispatch strategy for wind power plant considering dynamic wake effect

Inappropriate active power dispatch strategies can diminish the active power support capability (APSC) of the wind power plant (WPP) due to the wake effect. In existing strategies, the WPP’s APSC and the time delay of wake effect are not thoroughly investigated. This paper proposes an active power dispatch strategy to increase the WPP’s APSC while tracking the power reference. First, WPP’s temporary and sustained APSCs are analyzed considering dynamic wake effect. Correspondingly, the total stored kinetic energy and increasable power of WPP are introduced as evaluation indicators of the capabilities. Furthermore, a bi-level control framework is proposed to accomplish the dispatch task in different timescales. Aiming at improving WPP’s temporary and sustained APSCs comprehensively, the operating status references of each WT, including the power reference and pitch angle, are optimized in the WPP layer. Taking the time delay and nonlinearity of wake effect into account, the receding horizon optimization is solved in a finite time domain using nonlinear model predictive control (NMPC). During the sampling interval of the NMPC, a coordinated control in the WT layer is developed to modify the active power reference dispatched by the WPP layer in case the wind speed fluctuates. Finally, extensive case studies show that the WPP’s temporary and sustained APSCs are improved with the proposed strategy in different wind conditions and power references.

Roles of Metal Oxide Nanostructure-Based Substrates in Sustainable Electrochemical Water Splitting: Recent Development and Future Perspective

Increasing energy demand to find everlasting and eco-friendly resources is now mainly dependent on green hydrogen production technology. Water electrolysis has been regarded as a clean route for green H2 production with zero carbon emission, but different bottlenecks in the development of electrodes impeded its realization. Recently, transition metal oxides (TMO) have gained tremendous attention as suitable cathodes and anodes due to their sustainability under harsh conditions, high redox features, maximum supportive capability, easy modulation in valence states, and enhanced electrical conductivity. In this review, we have highlighted the role of transition metal oxides as active and supported sites for electrochemical water splitting. We have proposed different perspectives for the rational design of TMO-based electrode materials, i.e., electronic state modulation, modification of the surface structure to control the aerophobicity and hydrophilicity, acceleration of the charge and mass transport, and stability of the electrocatalyst in harsh environments. We have systemically discussed the insights into the relationship among catalytic activity, certain specified challenges, research directions, and perspectives of electrocatalysis of the OER and HER.

PERCEIVED ORGANIZATIONAL SUPPORT PENILAIAN KINERJA DAN INFORMATION TECHNOLOGY CAPABILITY PENGARUHNYA TERHADAP KINERJA KARYAWAN

The purpose of this study is to analyze Perceived Organizational Support (POS), Performance Assessment and IT Capability affect employee performance. Respondents from this study were all employees, namely as many as 75 people, data collection was carried out through a survey with a questionnaire instrument, and data analysis used was multiple linear regression, while F-test and t-test were used to test the hypothesis. The results of this study indicate that POS, Capability of IT, and performance appraisal partially have a significant effect on employee performance, while the hypothesis test as a simultaneously stated that POS, Capability of IT, and performance appraisal have a significant effect on employee performance. This indicates that to improve employee performance, organizational support, IT skills and performance appraisal of employees in the company are needed.

Fuzzy-based coordinated control and parameter correction strategy for speed controller of PMSG wind turbine in frequency response

The purpose of frequency response of PMSG wind turbine is to provide additional energy support to the power system’s frequency regulation demand through its rotor kinetic energy. However, the inherent control loop represented by the PMSG speed controller, and its inherent control purpose is to maintain a stable operation of the rotor speed, thus the difference between these two control blocks will lead to a conflict situation between frequency response performance and operation safety of the wind turbine. Therefore, a novel fuzzy-based coordinated control and parameter correction strategy for speed controller of PMSG wind turbine in frequency response is proposed in this paper. First, to clarify the function role of key parameters of the wind turbine in frequency response process, a mapping equivalence model consisting of wind turbine’s frequency response parameters and operation states is proposed by establishing the energy correspondence relationship between PMSG rotor kinetic energy, de-loading reserve by pitch angle control and power demand of frequency response. Then, the frequency response performances of the speed controller’s parameters are tested under various wind speeds. Moreover, based on the fuzzy logic algorithm, a dynamic operation strategy for the wind turbine’s speed controller is proposed to improve the frequency response performance, which alleviates its conflict against the PMSG frequency response control block. Finally, a simulation model is built to verify the proposed strategy under various wind scenarios. The test results demonstrate that the frequency response performance and the speed controller’s inherent control function of the PMSG-wind turbine can be effectively coordinated by deploying the proposed strategy, and the frequency support capability of the power system is effectively improved.

Abstract B033: Determining the tumor supportive and inhibitory capabilities of cancer associated fibroblast subpopulations in central nervous system metastasis. [R

Abstract Central nervous metastases (CM), like all tumors, are surrounded by a complex tumor microenvironment (TME) comprised of a meshwork of extracellular matrix (ECM) proteins and an assemblage of cell types including endothelial cells, pericytes, immune cells, and cancer-associated fibroblasts (CAFs). We have previously shown that CAFs can either support or inhibit tumor growth, suggesting that CM CAFs comprise a heterogenous subgroup of cells. Recently we reported, based on literature in other cancer types, that CAFs can be categorized into four main subpopulations: ‘desmoplastic’, ‘immune’, ‘contractile’ and ‘aggressive’. Accordingly, the purpose of our study is to identify CAF subpopulations in the TME of CM and determine their impact on CM growth. In order to identify CM CAF subpopulations and their respective markers, we performed single cell RNA sequencing (scRNA-seq) on 7 CM patient tissues and 4 patient-derived CM CAF cell lines established in our lab. We then used fluorescence-activated cell sorting (FACS) to enrich different CAF subpopulations in CAF cell lines for further molecular and functional in vitro and in vivo characterization. ScRNA-seq data in 7 CM tissues revealed the presence of CAFs. Upon further analysis, we identified the desmoplastic, immune, contractile, and aggressive CAF subpopulations. In the CAF cell lines, we identified the desmoplastic and aggressive CAF subpopulations. We propose that desmoplastic CAFs are tumor inhibitory and aggressive CAFs are tumor supporting. The desmoplastic subpopulation is characterized by high expression of Immunoglobulin Superfamily Containing Leucine Rich Repeat (ISLR) and low expression of a classic tumor supportive CAF marker Actin Alpha 2, Smooth Muscle (ACTA2, a-SMA). ISLR has recently been reported to be overexpressed in CAFs with tumor inhibitory capabilities in other cancer types. The aggressive subpopulation shows low ISLR expression and high a-SMA expression. FACS on one of the patient-derived CM CAF cell lines using ISLR antibody enriched ISLRhigh CAFs, with remaining CAFs confirmed to be ISLRlow. Further western blotting analysis revealed lower expression of a-SMA in ISLRhigh cells as compared to ISLRlow cells. This reciprocal expression of ISLR and a-SMA could represent the molecular basis driving the phenotype of desmoplastic and aggressive CAF subpopulations. Further in vitro and in vivo experiments are currently underway in our lab to determine the necessity and sufficiency of ISLR and a-SMA in determining tumor supportive capabilities of both desmoplastic and aggressive CAFs. The present study improves our understanding of the CM TME, which ultimately will help establish new strategies to harness the cancer restraining capabilities of tumor inhibitory CAFs in clinic to improve outcomes for patients with CM. Citation Format: Thomas Simon, David N. Buckley, Gerald C. Gooden, Ben Y. Tew, Gabriel Zada, Bodour Salhia. Determining the tumor supportive and inhibitory capabilities of cancer associated fibroblast subpopulations in central nervous system metastasis. [R [abstract]. In: Proceedings of the AACR Special Conference: Cancer Metastasis; 2022 Nov 14-17; Portland, OR. Philadelphia (PA): AACR; Cancer Res 2022;83(2 Suppl_2):Abstract nr B033.

영유아교육기관 교사의 놀이신념과 교수창의성이 놀이지원 역량에 미치는 영향

Objectives The purpose of this study was to examine the effects of play beliefs and teaching creativity of teachers at early childhood educational institutions on play support competency.&#x0D; Methods The subjects of this study were 287 teachers at day care centers and kindergartens in Busan and Gyeongsangnam-do. The analysis method was Person's product-moment correlation using SPSS 23 program to examine the relationship between teacher's play belief, teaching creativity, and play support competency, and multiple regression analysis was conducted to verify the influence of teacher's play belief and teaching creativity on play support competency.&#x0D; Results As a result of data analysis, first, there was a positive correlation between teachers' play beliefs, teaching creativity, and play support competency. Second, among the sub-variables of play support competency, teacher's teaching creativity showed higher explanatory power in internal motivation, play goal, play design, and play operation, and teacher's play belief showed higher explanatory power in teacher's emotion and attitude, play support improvement effort, knowledge, play environment creation, and infant evaluation.&#x0D; Conclusions The results of this study are significant in that it reminded the importance of teachers' play beliefs, teaching creativity, and play support capabilities in order for play-based education and childcare courses to be well realized in early childhood education institutions, and that teachers' play beliefs and teaching creativity should be promoted in order to enhance teachers' play support capabilities.