=Paper= {{Paper |id=Vol-2359/paper12 |storemode=property |title=Non-player character as a companion in cognitive rehabilitation for adults – Characteristics and representation |pdfUrl=https://ceur-ws.org/Vol-2359/paper12.pdf |volume=Vol-2359 |authors=Mareike Gabele,Andrea Thoms,Julian Alpers,Steffi Hußlein,Christian Hansen |dblpUrl=https://dblp.org/rec/conf/gamifin/GabeleTAH019a }} ==Non-player character as a companion in cognitive rehabilitation for adults – Characteristics and representation== https://ceur-ws.org/Vol-2359/paper12.pdf
                                   Non-player character as a companion
                                   in cognitive rehabilitation for adults -
                                     Characteristics and representation

                                       Mareike Gabele1,2, Andrea Thoms3, Julian Alpers1,
                                            Steffi Hußlein2 and Christian Hansen1
                                        1 Otto von Guericke University Magdeburg, Germany
                                   2 Magdeburg-Stendal University of Applied Sciences, Germany
                               3 HASOMED GmbH, Paul-Ecke-Straße 1, 39114 Magdeburg, Germany

                                                mareike@isg.cs.uni-magdeburg.de



                           Abstract. A lack of social support reduces the chances of successful rehabilita-
                           tion. However, the social environment changes considerably during this time.
                           Therefore, fostering consistent social contacts is highly relevant. To address so-
                           cial relatedness in software-based cognitive therapy during rehabilitation we in-
                           tend to use a non-player character as a companion. In this work we analyze pos-
                           sible forms of representation of the companion based on required characteristics,
                           age and gender to achieve this goal. These were set in relation to age and gender
                           of the user. Three female and three male companions in three age groups were
                           created and subsequently tested in an explorative feasibility study with 40 partic-
                           ipants. 50% of participants preferred a female middle-aged companion, 25% a
                           younger male. Older companions were chosen only by women. Regarding the
                           gender, 62.5% chose a female companion. We present an orientation for devel-
                           opment of non-player characters as companion in software-based training for
                           cognitive rehabilitation.

                           Keywords: Non-player Character, Cognitive Rehabilitation, Social Relatedness


                    1      Introduction

                    Software-based training is used in cognitive rehabilitation as a successful therapy for
                    brain damage [1]. Depending on the damaged region of the brain, cognitive deficits
                    such as in working memory, logical thinking, visual processing or attention may result.
                    In addition, motoric restrictions, speech and language disorders can occur. Strokes are
                    the main cause of acquired disability in adulthood [2]. Accidents with brain damage
                    can also be a cause. Frequent and regular training in inpatient and subsequently in out-
                    patient rehabilitation and / or home training is important for successful rehabilitation
                    [3]. The success may take months to years and cannot be guaranteed. A high level of
                    social support leads to a faster and better rehabilitation after a stroke. In contrast, social
                    isolation is a particular risk of poor rehabilitation outcomes [4] or higher mortality rate
                    [5]. Especially in eHealth, dropping out before completing the goal is high [6]. In home




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                    training, patients need a high level of motivation in order to carry out the training, as
                    the training is no longer supervised by therapists at every session, as in the clinic.
                       Existing social contacts can be reduced considerably by the stay in the clinic, the
                    temporary or complete leaving of the workplace and motor and cognitive restrictions.
                    To overcome this problem, we want to address the human needs for consistent and
                    motivating social support in software-based cognitive training during rehabilitation.
                    Therefore, we propose integrating a non-player character (NPC) as a companion within
                    the training software, who will accompany the patient during the whole time of reha-
                    bilitation (in the following text this NPC is only called companion). The companion
                    should neither replace the therapist, nor real social interaction, but offer a stable accom-
                    paniment.
                       The target group are patients with acquired brain damage who are undergoing cog-
                    nitive rehabilitation. There is a large number of studies that deal with the relationship
                    between therapist and patient and deal with different effectiveness factors. This in-
                    cludes, among other things, the therapist's empathy and appreciation [7, 8]. Similar
                    characteristics may be assumed for a companion. However, there are large demographic
                    differences between patients who perform software-based therapy. Therefore, the re-
                    quirements for the characteristics of a companion can vary widely. Likewise, it can vary
                    how a companion is perceived and which characteristics are attributed to him. To ana-
                    lyze this, we developed a questionnaire, visualized and integrated different characters
                    in gender and age, and evaluated them exploratively in a feasibility study. We focused
                    on the following research questions:

                       Q1. Which characteristics are desired for a companion?
                       Q2. Which age of the companion is preferred and why?
                       Q3. Which gender of the companion is preferred and why?
                       Q4. Does the reason for the selection match the previously desired characteristics?
                       Q5. What are the characteristics of the choice of a companion in terms of the age
                       and gender of the participants?

                       The main contribution of this paper is to analyze which characteristics are needed
                    for a companion in cognitive rehabilitation therapy, and what type of companion these
                    characteristics are attributed to, by which participants. In the cognitive field, analyses
                    for the representation of companions in software-based therapy, especially with regard
                    to social relatedness, have so far been neglected. Our results indicate an approach for
                    the use of NPCs as a companion in software-based cognitive training in rehabilitation
                    to create lasting social in-game relationships and create possibilities of its use. This may
                    promote the feeling of social relatedness, motivate intrinsically and support the patient
                    mentally during the rehabilitation process in the long-term [9].
                       In the following we first give an overview of social relatedness, avatars and NPCs
                    used in games and therapy. Then we present the different NPCs we developed in dif-
                    ferent gender and age groups and the execution of a feasibility study. We sorted the
                    results, visualized and analyzed them. Finally, we discuss the results and possible fur-
                    ther uses of NPCs in software based training in cognitive rehabilitation.




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                    2      Related Work

                    Social relatedness, along with autonomy and competence, is one of the central factors
                    of self-determination theory, which describes the psychological needs for intrinsic mo-
                    tivation [10]. In games, they are able to influence the fun of the game and the future
                    gameplay independent from each other [11]. We want to use this to support motivation
                    of the patient in therapy by promoting social relatedness. Social relatedness describes
                    the human need for integration into a social environment and belongingness [12]. Re-
                    inforcing this feeling encourages people to become more involved themselves [13].
                    Common goals and experiences, as well as highlighting cooperation can strengthen the
                    sense of social relatedness of team members [14]. Social structures can arise on inter-
                    personal contacts in the real or virtual world, but also on contact with non-realistic
                    characters. The cooperation with teammates (for example NPCs) successfully affects
                    the sense of social relatedness [15]. Elements that are assigned to the area of socializa-
                    tion indicate only neutral to positive influence on players [16].
                       Gamification elements are elements that are typically used in games, but are inserted
                    in a different, non-game context [17]. Their effectiveness, is not only based on their
                    general, but on their conscious, conceptually targeted use [18] and their perceived value
                    to the user [19]. Therefore, the mechanics of the NPC shall be used as a gamification
                    element in cognitive rehabilitation and be adapted to the needs of the patient. Serious
                    games are games that pursue a goal outside the game [17], such as therapy [20] or
                    education [21]. In the field of motoric rehabilitation, it has been shown that serious
                    games increase the effectiveness of the corresponding training. However, they combine
                    different gamification elements, but analyses are required for individual gamification
                    elements [22].
                       Avatars are used in current software-based training for self-representation to reflect
                    the patient's movements or to demonstrate desired movements [23]. This shows that
                    digital characters in rehabilitation software have already been used with success, which
                    shows a positive basis for our research. However, these are oriented towards the func-
                    tionality of the exercise in motoric instead of cognitive rehabilitation and representation
                    of the user. Avatars are also used in serious games as player-character for cognitive
                    training of attention for children with attention deficit hyperactivity disorder (ADHD)
                    [24]. As another possibility of using digital characters, we want to propose an NPC in
                    our work that guides the patient. The visualization of NPCs is based on the influence
                    of social norms and should correspond to the expectations of the user. This results in
                    expectation regarding appearance, behavior and role models, which in turn influences
                    the behavior of the player [25]. Therefore we analyze whether there is a trend for ex-
                    pectations. And if there is a trend, we want to use it to influence the patient's behavior
                    positively in the use of the software-based training.
                       In computer games, companions are often expected to have the basic attributes
                    skilled, helpful, nice, attractive and naive [26]. Further, the game identification of the
                    players is related to the interaction with the companions [27]. However, the focus of
                    such research is often on a younger healthy target group which plays for fun.




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                    3      Explorative Feasibility Study

                    3.1    Development of Elements of the Study
                    In this study, we analyzed the characteristics required for a companion of patients in
                    cognitive rehabilitation. In addition, we analyzed preferences for different types of
                    companions in the representation. For this, we created visual representations of three
                    female and three male companions (Fig. 1). For each group one companion was created
                    in the range under 35 years (young), 35 - 49 years (middle aged) and over 50 years
                    (older). These were developed iteratively on the basis of feedback from three experts
                    in the field of rehabilitation (psychology, management, design). A consistent graphic
                    style and consistent clothing is used to minimize further influences by personal prefer-
                    ences e.g. in the color or clothing style and a thereby possible bias. The choice of the
                    skin color of the NPC is based on the reason that the study was carried out in Europe
                    and that the participants are most accustomed to it in their everyday life. Primarily the
                    face is modified by the change of the age and age-appropriate representation of the hair,
                    secondarily the age- and gender-appropriate body form.




                    Fig. 1. Visualization of the six different companions used in the study, A-C Female (age young
                    to old), D - F Male (age young to old).


                    3.2    Methods and Material
                    An explorative feasibility study was conducted based on a structured interview. First,
                    the participants were informed about the voluntary participation, goals and background
                    of the study. It was also brought to mind that personal perception and subjective opin-
                    ions are at the center of attention. The time of rehabilitation was compared to a long
                    hike. We asked closed questions with predefined answers to focus a decision between
                    the companions. In addition, we asked open questions with free responses on charac-
                    teristics and the reasons for the selection of the chosen companion. In this way, we




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                    wanted to identify the aspects that are personally relevant to the participant without
                    influencing him or her beforehand. With regard to our questions (Q1 - Q5) we pro-
                    ceeded as follows:

                          a) Participants were asked what characteristics a companion needs to have in or-
                             der to take the companion on the long rehabilitation trail (open) (Q1)
                          b) Selection of one of three possible female avatars as companions (A, B, C)
                             based on pictures (closed) and the reason for the selection (open) (Q2)
                          c) Selection of one of three possible male avatars as companions (D, E, F) based
                             on pictures (closed) and the reasons for the selection (open) (Q2)
                          d) Selection between the two avatars previously selected in b) and c) as final
                             selection based on pictures (closed) and the reasons for the selection (open)
                             (Q3 and Q4)
                          e) Collection of demographic data: age group (<20, 20-29, 30-39, 40-49, 50-59,
                             60-69, 70-79, >80), gender and existence of acquired brain damage (Q5)

                       With regard to the open questions, we summarized the same answers, counted the
                    frequency of naming and sorted the answers based on this. Afterwards, for question a),
                    similar characteristics were clustered. Concerning b), c) and d), we analyzed the occur-
                    rence for conspicuities with regard to age and gender of the participants.


                    3.3        Participants

                    The study was conducted at the open day of a german University Hospital with attached
                    outpatients clinic for cognitive neurology in September 2018. 40 participants took part
                    in the study (female: n=24; male: n=16). They are composed of patients in cognitive
                    rehabilitation (n=5) and persons with professional or personal knowledge and connec-
                    tion to the topic and / or interest in (n=35). The age groups ranged in steps of ten from
                    under 20 to over 70. According to experts, the age distribution curve reflects the ap-
                    proximate distribution of patients in cognitive rehabilitation and is shown in Fig. 2.




                                          Fig. 2. Age distribution of participants in the study.

                    The participants were personally asked about their interest in participating in the study.
                    They were selected by us on the basis of their age, which fits approximately to this
                    distribution, and otherwise without further selection criteria. All participants come from




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                    the European cultural area. All participants took part voluntarily in the study and were
                    not rewarded. The study was conducted in Germany.


                    4       Results, Clustering and Analytical Procedure

                    In the following, the answers, frequencies and / or percentwise distribution of answers
                    for a) - d) are presented. The results for step a) are shown in Table 1. It shows the
                    characteristics that participants list a companion should have. After sorting and cluster-
                    ing the answers, a focus on character, knowledge and interpersonal behavior is appar-
                    ent. The results for step b) are shown in Fig. 3.1. In this selection of female companions
                    in different ages, the middle-aged female companion B is preferred. The results for step
                    c) are shown in Fig. 3.2. In this selection of male companions in different ages, the
                    younger male companion D is preferred. The results for step d) are shown in Fig. 3.3.
                    A final selection was made between the previously selected female and male compan-
                    ion. 50% of the participants preferred the middle-aged female companion B. Addition-
                    ally, for b), c) and d), Fig. 3 lists the reasons for the selection on the right axis, or below.
                    The relations resulting from inclusion of e), the demographic data, between the chosen
                    companion and the age and gender of the participant are described in Table 2 and at the
                    end of this section. The focus here is on conspicuities that emerged in the data analysis.

                    Table 1. Sorted and clustered answers for a). The number in brackets shows the frequency of
                    naming by all participants. Characteristics without brackets were mentioned once.

                      Character (44): friendly (4), authoritative (4), empathetic (4), relaxed (3), patient (3),
                      clear (3), charismatic (smile / be positive) (2), open-natured (2), demanding (2), seri-
                      ous (2), nice, considerate, understanding, uncomplicated, not too soft, energetic, as-
                      sertive, distinct, strict, resolute, not so serious but funny sometimes as well, also some-
                      times sarcastic / black humor, objective, helpful, honest

                      Type / Optical (4): beeing able to walk well, sporty, more dynamic than oneself, both
                      feet on the ground

                      Behavior / Knowledge (23): competent (7), knows what the best way is especially
                      for me (giving feedback) (5), knows the situation and knows what it is like and how
                      to deal with the situation (2), someone who has gone through this himself, able to
                      give expert advice, giving feedback even if it is negative, explain what makes sense /
                      what doesn't, giving background information, open to questions, interested in the
                      field, bringing the goals I have in line with the therapy, dealing with it individually

                      Interpersonal (27): motivating (6), when I don't feel like it / have a low point, moti-
                      vate me to do it (3), must be able to talk to him (2), must be able and willing to lis-
                      ten (to one's own problems) (2), friend (2), relaxed atmosphere, person in a position
                      of trust, right chemistry, says what to do, takes the lead, pays attention if one does
                      the tasks, supporting, doesn't force you, calming, provide security, able to catch me,
                      get to know each other on a neutral basis




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                    Fig. 3. 3.1) percentwise selection of female companion and reasons for selection, 3.2) per-
                    centwise selection of male companion and reasons for selection, 3.3) percentwise selection of the
                    final companion.

                    With regard to Fig. 3.3, the reasons for selection after clustering by frequency of nam-
                    ing are as follows: sex (11), animating / supporting (6), competence (6), sympathy (6),
                    empathy (5), sense of security (5), trust (4), assertiveness (4).




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                    Table 2. 2.1) percentwise selection of companions in b) and c) based on age group of the partic-
                    ipants, 2.2) percentwise selection of companions in b) and c) based on gender of participants,
                    2.3) percentwise final selection of companions in d) based on age group of the participants,
                    2.4) percentwise final selection of companions in d) based on gender of participants

                                             Chosen companion according to b) and c)
                                  female female female            male   male     male
                     Participants    A      B       C              D       E        F
                     2.1) age
                     Young (<30)    5%    7,5%   2,5%            12,5% 2,5%         0
                     middle aged
                     (30-59)       7,5% 42,5%      5%            32,5% 17,5%       5%
                     old
                     (>60)         7,5%   15%    7,5%            27,5% 2,5%         0
                     Overall       20%    65%     15%            72,5% 22,5%       5%
                     2.2) gender
                     women        20,83% 54,17% 25%             83,33% 8,33% 8,33%
                     men          18,75% 81,25% 0%              56,25% 43,75% 0%

                                              Chosen final companion according to d)
                                  female female female female male        male     male  male
                     Participants    A      B       C     overall  D        E        F  overall
                     2.3) age
                     Young (<30)     0    2,5%      0               0     2,5%       0
                     middle aged
                     (30-59)      5,00% 32,5% 2,5%                15%     7,5%     2,5%
                     Old (>60)     2,5%   15%     2,5%            10%       0        0
                     Overall       7,5%   50%      5%             25%     10%      2,5%
                     2.4) gender
                     women        8,33% 45,83% 8,33% 62,5% 33,33%           0     4,17% 37,5%
                     men          6,25% 56,25%      0     62,5% 12,5% 25%            0  37,5%

                    Taking account of e), the demographic data, only 7.5% prefer the oldest companion
                    (female C and male F) in the final selection (Table 2.3). Of these, all were female in the
                    age range between 40 and 69. The young female companion (A) was chosen by 7.5%,
                    of whom 5% were female in the age range between 50 and 69 and 2.5% male in the age
                    range between 20 and 29. The middle-aged male companion (E) was chosen in the final
                    selection exclusively by men (Table 2.4) who were equally distributed between the age
                    ranges from under 20 to the ages of 50 - 59. The older man (F) was chosen exclusively
                    by women between the ages of 50 and 59.
                       Regarding only the participants with brain damage and cognitive rehabilitation, 60%
                    chose the middle-aged female companion (B), 20% the younger female companion (A)
                    and 20% the younger male companion (D). This results in 80% of the participants with
                    brain damage who chose a female companion.




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                    5      Discussion

                       In this work, requirements for the characteristics of a virtual companion in software-
                    based cognitive therapy in rehabilitation and selection criteria were analyzed. These
                    were based on age and gender of companions and participants.
                       To support the patient's motivation, the companion can guide him starting from the
                    initial training. He can show the patient on a map his progress in rehabilitation, remind
                    him of good experiences, note frequent mistakes made during training and can remind
                    for the next training. Comparable use cases, such as informing about a task or helping
                    the player, were included in classifications within research in games [25]. The com-
                    panion's skills and clothing improve through regular training or can be selected. This
                    enables companion to develop further together with the patient. The aim is to support
                    the regular performance of the training required for rehabilitation.
                       Software-based training in cognitive therapy often involves several individual train-
                    ings (e.g. for deficits in attention, memory or executive functions). These differ in rules
                    and tasks. In the therapy for adults the trainings are carried out one after the other. There
                    are rarely integrated characters or social relatedness. Through our suggested use of
                    NPCs these can be modified. They can be used in individual trainings as well as in an
                    overarching role to connect the trainings. Previous research has shown that due to social
                    norms there are expectations of the user to the NPC [25]. Based on this, the patient's
                    behavior could be positively influenced by a companion considered as positive as pos-
                    sible, which may support regular training. This will be considered in further studies.
                       In the presented study the desired companion is predominantly described as an em-
                    pathetic friend and competent at the same time (Q1). The companion has to take the
                    leading role and be motivating, but also strict if necessary. This shows the desire for
                    trust and guidance in a situation that cannot be assessed by the individual because the
                    necessary skills are lacking. The focus is therefore not on appearance. That is highly
                    relevant for the development of a companion for use in software-based therapy for
                    which the characteristics analyzed in a) should be in the focus. Developed NPCs should
                    also be evaluated on this.
                       The stated needs with regard to characteristics and that being naive is no require-
                    ment, differs from the expectations of a classic companion in computer games. Rather,
                    a combination of companion and mentor is the result. The mentor is additionally de-
                    scribed by Rogers et al. [26] as wise and intelligent, but also old, which does not cor-
                    respond to the expectations regarding a companion in rehabilitation. This implies that
                    the requirements for the use of a companion in rehabilitation differ from those of normal
                    players. Existing classifications [25, 26] are an important basis for comparing these
                    systems with the needs of patients and possibly extending them.
                       The selection of the younger to middle-aged companion (Q2) could be based on the
                    fact that in long-term strength may be needed for support. If older avatars are chosen,
                    patients frequently stated that the reason is due to the closeness to one's own age. This
                    may indicate the need to bring up empathy for one's own situation. On the basis of age
                    (Q3), the middle-aged (female companion B) is preferred for the female companions
                    and among others described as pleasant and competent. Among male companions, the




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                    younger one (male companion D) is preferred and described as sympathetic and dy-
                    namic. The desired characteristics, which were stated previously by each participant,
                    were later often linked to the choice of gender when the reasons for the final selection
                    were stated. The overall desired qualities for the companion are predominantly at-
                    tributed to women in everyday life, which could explain the final tendency towards the
                    female companion. Compared to the previous assessment (Q4), however, none of the
                    participants had expressed gender-specific wishes. The companions selected in the final
                    selection were otherwise attributed congruent characteristics as desired before. These
                    were thus confirmed based on the representation of the companions. This may show on
                    the one hand that in Q1 the gender classification did not seem relevant for the partici-
                    pants. On the other hand, it may also show that previous characteristics were assigned
                    to the characters shown. Regarding the choice of age and gender of respondents (Q5),
                    it was found that women also chose the older characters, while men did not. Women
                    were more likely to choose the younger male companion, men also the middle-aged.
                    The younger female companion is preferred by older women and younger men. Here
                    various aspects, such as the protective instinct of the older participants or the sexuality
                    of the younger participants may be involved. Due to the low final selection of some of
                    the companions, this can only be seen as an indication.
                        The comparison of data between participants with and without brain damage shows
                    that the distribution of the selection is very similar. That is apparent from the fact that
                    the trends in the selection of companions, both female and male, and the final selection
                    correspond. It can be assumed that the presence of brain damage does not change the
                    needs in the presented situation, because all participants were asked about their personal
                    preferences. However, the observed trend cannot be generalized due to the small sample
                    of patients. Persons without acquired brain damage know the situation of patients, but
                    are in a different emotional situation. The acquired brain damage and the resulting ex-
                    perience may lead to further effects in the use of NPCs. Further studies should be car-
                    ried out with patients and the effect on patients during use of NPCs should be examined
                    more closely. A further influence on the data can be assumed by the unequal distribu-
                    tion of the participants between men and women. However, if the percentual distribu-
                    tion of the final selection is compared between female and male participants, it is ex-
                    actly the same. 62.5% of both men and women chose a female companion and 37.5%
                    a male companion in the final selection (Table 2.4). From this, it can be assumed that
                    the gender of the participants does not influence the distribution of the selection of the
                    gender according to the companion. In this study, one visualization was used per age
                    and gender. There may be an influence from preferring a particular graphical represen-
                    tation. This can be further investigated by using different visualizations per category.
                        Due to the exploratory approach to the feasibility study, the results of the individual
                    categories should be considered as trends. Slight to strong deviations from the trend can
                    arise individually due to the unique personalities and resulting needs of patients. The
                    results generally represent the field of cognitive rehabilitation. Whether there are dif-
                    ferences between various neurological diseases needs further analysis. The participants
                    come exclusively from the European cultural area, so the results can only be related to
                    this particular demographic. Therefore, the results provide a basis for further studies to
                    consider the conspicuous results found here separately.




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                    6      Conclusion

                    This work shows an analysis of possible representations of NPCs as a companion in
                    cognitive therapy during rehabilitation based on characteristics, age and gender of com-
                    panion and participants. This was done using three visualized female and male charac-
                    ters in each case as selections in combination with a questionnaire on preferred charac-
                    teristics and reasons for selection. Results show a trend to use a middle-aged female or
                    a younger male companion for software-based cognitive training in rehabilitation. The
                    relevant characteristics are to be competent and give feedback, motivating but at the
                    same time determinant, friendly and empathetic. It worth further investigation because
                    a trend has been shown, which should be considered further if companions are inte-
                    grated in cognitive training software. Furthermore, various possible uses for the com-
                    panion should be evaluated. In the future, it could be possible to present the progress of
                    the patient, to remember training times or to give hints for improvements in training
                    and everyday life using the optimized companion as an application purpose.

                    Acknowledgments. We would like to thank Juliane Weicker, Angelika Thöne-Otto
                    and Michael Preier for support with professional questions and conducting the study.
                    This work was funded by the European Regional Development Fund under the opera-
                    tion numbers ZS/2016/04/78123 and ZS/2017/01/83843 as part of the initiative
                    ”Sachsen-Anhalt WISSENSCHAFT Schwerpunkte” and FEM-POWER under the
                    operation number ZS/2016/09/81572.


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