3.5.4. Risks for Recipients

To the best of our knowledge, until now there have been no cases of donor-to-recipient transmission of SARS-CoV-2. On the other hand, recipients run the risk of nosocomial SARS-CoV-2 infections during the pandemic. Asymptomatic patients infected with SARS-CoV-2 can spread the virus. It is currently unknown whether asymptomatic individuals are only asymptomatic initially after contracting the infection, or if they remain asymptomatic throughout the course of the SARS-CoV-2 infection. In spite of the asymptomatic carrier state, these individuals may transmit the virus, although the exact mechanism of acquiring and transmitting the virus requires further study [27,28]. Even in a convalescent patient, a high sputum viral load has been demonstrated, raising concerns about prolonged viral shedding of SARS-CoV-2 after recovery [28].


**2. Standardization of the communication system brought by IEC 61850**

IEC 61850 standard was published in 2003 to cover the inter-substation communication and since that the standard has expanded and evolved. Nowadays it consist of around 35 parts covering many area of power system protection an automation. The later development has expanded its use intr-substations covering wider area in the grid including distributed generation and reaching up to the control center. IEC61850 cover all various aspects, which are common and related to the substation site e.g. SCD files that specify communication protocols, SAS configuration and conformity over the channel. While, grouping and organizing SAS parameters in applications level by means of syntax and semantics in IEDs they left for the software design engineers.

IEC 61850 developed based on the associated architectural construct "abstracting" data object definition and its services. The data structures (data objects along with the associated services) are abstracted in a way that severely independent from communication links. The data structure support all the aspect of the SAS based on the monitoring, controlling and protection functions along with their associated services in order to execute and facilitate the energy system operation. Therefore, data object can be mapping over any IEC 61850 defined protocol that can meet the best requirements need.

At this point, the major focusing of the IEC 61850 specification can be organized into three main issues;

Firstly, (data object model), SAS data object that associated with the available measurements, SAS functions (functional model) and IEDs name should be standardized in a way that provides to the IEDs a shared vocabulary that support the intended semantic meaning.

Secondly, abstract communication services interface (ACSI), accessing scheme to the available data can be defined as a services that specified in different standardizing ways over the assigned communication protocols.

Lastly, eXtendable Markup Language (XML) is selected to describe all the SAS data (data object models, configuration information and communication protocol) and organized in different SAS IEC 61850 extensions files. These files can be shared among all the SAS IEDs, networks and power system.

The scope of the first version of the IEC 61850 standard is composed of 10 major parts that together define the various aspects and the entire requirement that has to be fulfilled by SAS. The main drive is to achieve interoperability among the IEDs within the SAS. Where, the positive impact of the IEC 61850 standard in SAS operation cost it is clearly known in terms of increasing the power quality and reducing the outage response [12]. However, this goal requires paying attentions on how to implement the IEC 61850 standard in order to build, integrate and operate the SAS. While, rapidly transforming of the energy systems from analog to digital environment, which need huge amounts of real-time data to be shared based on their efficient operation. Therefore, IEC 61850 standard along with its uniqueness properties, that originated in hierarchy principle from the bottom to up which are dependent from the underlying operating technology. This will allow the Standard to operate over the stat-of-the-art technologies. The standard will cover all the electrical system aspects as well as the standard will provide a novel set of functionalities, which are not, exists within the legacy SAS operation. At this point and from the IEC 61850 implementation point view, the standard will be an enabler to upgrade and utilize the fullest functionality, where their operation and implementation are depend on sharing information among different LNs located on the same LD within an IED or different LDs located on different IEDs. Therefore, numerous of benefits will be achieved that included but not limited [13].


**4. Conclusions**

We measured the importance of 11 SD criteria as perceived by the general public in Japan, South Korea, Thailand, and Vietnam. The 11 SD criteria were accessibility, capability, convenience, efficiency, environmental capacity, diversity and choice, inclusiveness, resilience and stability, security, self-sufficiency, and social justice. We used an indirect stated preference approach and employed 58 questions in 6 domains.

The main findings and the answers to the three research questions are as follows:

goal based on the SD criteria. Perception of the importance of the domains may be more influential than that of the criteria;

• The order (rank) of importance of the 11 SD criteria differed by country to a certain extent, which may be related to the economic development of the countries. For example, environmental capacity was ranked lower, and was ranked inclusiveness higher in the countries with a higher per capita GDP (research question 1a).

The main academic contributions of this study perceived by the authors are the development of the method for measuring the importance of SD criteria and the results of attempting the measurement. As many studies at their initial stages have, this study has some limitations. First, this study focused on six domains, but there are others. Second, there were only four target countries. Expanding the scope and number of countries remains as a future research task. The same survey applying to a country at a different time also remains as a future task. A third limitation is that we did not identify what the explanatory variables of the predictors of the importance of SD criteria of general public are. To do so, in-depth analyses of the results are needed. The fourth limitation is the number of SD criteria. Establishing a more complete set of SD criteria and the questions that should be used to elucidate relevant responses also remains as a future research task. Finally, although we devised and employed an indirect stated preference approach in this study, the development of different approaches to measure the importance of SD criteria and to compare the results among the different methodologies should allow us to produce more reliable results in the future.

**Author Contributions:** Conceptualization, T.T., R.T. and Y.K.; methodology, formal analysis, investigation, visualization, supervision, writing—original draft preparation, T.T.; writing—review and editing, R.T. and Y.K.; funding acquisition, Y.K. and T.T. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research was conducted based on the research funded by the Environment Research and Technology Development Fund (S-11) of the Environmental Restoration and Conservation Agency, Japan.

**Conflicts of Interest:** The authors declare no conflict of interest.