Could it be that I am really done? With my life, yes! With the thesis, let's see...

abstractDE.tex

@@ -1,4 +1,42 @@
 %----------Kurzfassung DEUTSCH----------------------------------------------------------------
 
 \addsec{Kurzfassung}
-Deutschsprachige Kurzfassung...
+
+Tastaturen sind in der modernen Gesellschaft allgegenwärtig. Ob in
+Krankenhäusern, Einzelhandelsgeschäften, Büros oder zu Hause - die Tastatur ist
+nach wie vor das meistgenutzte Eingabegerät für fast alle, die mit einem
+Computer arbeiten. Einige Benutzer:innen empfinden jedoch irgendwann Unbehagen
+oder sogar Schmerzen bei der Verwendung einer Tastatur, da die Finger viele
+kleine und sich wiederholende Bewegungen ausführen müssen, um die Tasten zu
+bedienen. Daher versuchen wir in dieser Bachelorarbeit, ein alternatives, nicht
+uniformes Tastaturdesign zu evaluieren, bei dem jede einzelne mechanische Taste
+mit einer Feder ausgestattet ist, die einen Widerstand aufweist, der dem
+spezifischen Finger entspricht, der sie normalerweise bedient. Die Idee hinter
+diesem angepassten Design ist, insbesondere die schwächeren Finger zu entlasten
+und trotzdem die Produktivität beizubehalten oder sogar zu verbessern. Deshalb
+versuchen wir die Frage zu beantworten, ob eine Tastatur mit einer für jeden
+Finger angepassten Betätigungskraft einen positiven Einfluss auf die Effizienz
+und die allgemeine Zufriedenheit während der Benutzung hat. Darum haben wir die
+aktuelle Verfügbarkeit von Widerständen für mechanische Tastenschalter evaluiert
+und eine erste telefonische Befragung (n = 17) durchgeführt, um Präferenzen,
+Anwendungsfälle und bisherige Erfahrungen mit Tastaturen zu ermitteln. Darüber
+hinaus führten wir ein weiteres Experiment durch, bei dem wir die maximal
+ausübbare Kraft für jeden Finger in verschiedenen, mit dem Drücken einer Taste
+verbundenen Positionen maßen und im Anschluss als Grundlage für unser
+angepasstes Tastaturdesign verwendeten. Schließlich wurden in einer dreiwöchigen
+Laborstudie mit 24 Teilnehmern das angepasste Tastaturdesign und drei
+herkömmliche Tastaturen mit 35 g, 50 g und 80 g Betätigungskraft in Bezug auf
+Leistung und allgemeine Zufriedenheit miteinander verglichen. Die statistische
+Auswertung ergab, dass vor allem die Fehlerquote durch höhere Betätigungskräfte
+positiv beeinflusst wird und dass Tastaturen mit weder zu hohem noch zu geringem
+Widerstand generell am besten in Bezug auf die Schreibgeschwindigkeit
+abschneiden. Darüber hinaus waren die Ergebnisse für die angepasste Tastatur und
+die 50-g-Tastatur in allen Tests nahezu identisch, so dass wir keine
+signifikanten Verbesserungen in Bezug auf Leistung oder Zufriedenheit im
+Vergleich zu herkömmlichen Designs, welche Tastenschalter mit moderatem
+Widerstand verwenden, ableiten konnten. Wir kamen jedoch zu dem Schluss, dass
+das angepasste Design aufgrund der gleich guten Ergebnisse immer noch eine
+brauchbare Alternative ist und mit weiteren Verbesserungen, z. B. einer
+vollständigen Personalisierung des Federwiderstands für jede Taste,
+möglicherweise das Erlebnis bei der Verwendung und die Leistung für
+anspruchsvolle Benutzer:innen verbessern könnte.

abstractEN.tex

@@ -1,4 +1,51 @@
 %----------Zusammenfassung Englisch/Abstract----------------------------------------------------------------
 \addsec{Abstract}
 
-Here goes the abstract (English language)...
+Keyboards are omnipresent in modern society. Hospitals, retail stores, offices
+or at home, the keyboard is still, the main input device for almost anyone that
+interacts with a computer. However, at some point, many people experience
+discomfort or even pain while using a keyboard because of the many small and
+repetitive movements the fingers have to do to operate it. Therefore, in this
+thesis we try to evaluate an alternative, non-uniform keyboard design, where
+each individual \textit{mechanical} keyswitch is equipped with a spring, that
+features a resistance, appropriate for the specific finger usually operating
+it. The idea behind this adjusted design is to particularly reduce the load on
+weaker fingers and still pertain or even enhance typing
+performance. Additionally, we try to answer the question, whether or not a
+keyboard with, per finger, adjusted actuation force has a positive impact on
+efficiency and overall satisfaction. Thus, we evaluated the current availability
+of resistances for mechanical keyswitches and conducted a preliminary telephone
+interview (n = 17) to assess preferences, use-cases and previous experiences
+with keyboards. Further, we ran another preliminary experiment, where we
+measured the maximum applicable force for each finger in different positions
+related to keyboarding as a basis for our adjusted keyboard design. Lastly,
+during a three week laboratory user study with twenty-four participants, the
+adjusted keyboard design and three traditional keyboards with 35 g, 50 g and 80
+g actuation force where compared to each other in terms of performance and user
+satisfaction. The statistical analysis revealed, that especially error rates are
+positively influenced by higher actuation forces and that keyboards with neither
+to heavy nor to light resistance generally perform the best in terms of typing
+speed. Further, the adjusted keyboard and the 50 g keyboard performed almost
+identically in all tests and therefore we could not derive any significant
+improvements in performance or satisfaction over traditional designs that
+utilize keyswitches with moderate resistance. However, we concluded, that with
+the equally good results, the adjusted design is still a viable alternative and
+with further improvements, e.g., complete personalization of spring resistance
+for each key, could possibly enhance the user experience and performance for
+sophisticated typists.
+
+
+
+
+
+
+
+
+
+
+% Even though experts recommend to regularly take a break from
+% keyboard work to prevent such symptoms, these recommendations can rarely be
+% implemented in working environments, where productivity and tight schedules are
+% very common. If the pain or discomfort persists, people have to either reduce or
+% a completely stop working with a keyboard, which in some cases might even force
+% them to change their profession.

appendices.tex

@@ -3,62 +3,43 @@
 \appendix
 \section{Appendices}
 
-\subsection{Statista charts}
+\subsection{Go Typing Test - Self Programmed Typing Test Platform}
-\label{sec:a1}
+\label{app:gott}
+
 \begin{figure}[H]
   \centering
-  \includegraphics[width=0.9\textwidth]{images/GER_households_w_computer.png}
+  \includegraphics[width=1.0\textwidth]{images/gott_demo}
 \end{figure}
+
 \begin{figure}[H]
   \centering
-  \includegraphics[width=0.9\textwidth]{images/ITU_households_w_computer.png}
+  \includegraphics[width=0.67\textwidth]{images/gott_crowdsource}
 \end{figure}
+
 \begin{figure}[H]
   \centering
-  \includegraphics[width=0.9\textwidth]{images/erostat_ent_w_comp.png}
+  \includegraphics[width=1.0\textwidth]{images/gott_kcq}
 \end{figure}
 
-\subsection{Collection of available actuation forces for different keyswitch manufacturers}
+\begin{figure}[H]
-\label{app:keyswitch}
-
-To gather information about available actuation forces, the product lines of
-keyswitches for all well known manufacturers, namely Cherry, Kailh, Gateron,
-Matias, Razer and Logitech were collected. Since some of the key actuation
-forces listed on the manufacturers or resellers websites were given in \gls{cN}
-and most of them in \gls{g} or \gls{gf}, the values were adjusted to gram to
-reflect a trend that is within a margin of ± 2 g of accuracy. The results shown
-in \textit{Figure \ref{fig:iter}} are used to determine the minimum, maximum and most common
-actuation force for broadly available keyswitches.
-
-\begin{figure}[h]
   \centering
-  \includegraphics[width=0.9\textwidth]{images/keyswitches_brands.png}
+  \includegraphics[width=1.0\textwidth]{images/gott_ueq}
-  \caption{Available actuation forces for keyswitches of major keyswitch manufacturers}
-  \label{keys:actuation_force}
 \end{figure}
 
-\clearpage
+\pagebreak
 
-\subsection{Go Typing Test - Self programmed typing test platform for this thesis}
+\subsection{UX-Curves for All Participants and All Groups}
-\label{app:gott}
+\label{app:uxc}
 
-\begin{figure}[h]
+\begin{figure}[H]
   \centering
-  \includegraphics[width=0.9\textwidth]{images/gott_typing_test.png}
+  \includegraphics[width=1.0\textwidth]{images/ux_curve_results}
-  \caption{Go TyingTest (GoTT) - Typing test}
-  \label{gott:typing_test}
 \end{figure}
 
-\begin{figure}[h]
+\subsection{EMG Electrode Placement for All Participants}
-  \centering
+\label{app:emg}
-  \includegraphics[width=0.9\textwidth]{images/gott_contribute_text.png}
-  \caption{Go TyingTest (GoTT) - Text contribution section}
-  \label{gott:contribute_text}
-\end{figure}
 
-\begin{figure}[h]
+\begin{figure}[H]
   \centering
-  \includegraphics[width=0.64\textwidth]{images/gott_demographics_survey.png}
+  \includegraphics[width=1.0\textwidth]{images/collage}
-  \caption{Go TyingTest (GoTT) - Demographics survey}
-  \label{gott:demographics_survey}
 \end{figure}

chap1/introduction.tex

@@ -27,25 +27,72 @@
 % or even customizable keyboards, where an individual can select the actuation
 % force for each keyswitch individually.
 
-% In recent decades, computers and other electronic devices have become an
+In recent decades, computers and other electronic devices have become an
-% indispensable part of everyday life. Computers are used in almost every industry
+indispensable part of everyday life. Computers are used in almost every industry
-% \cite{iresearch_ent_w_comp, eurostat_ent_w_comp} and almost half of the
+\cite{iresearch_ent_w_comp, eurostat_ent_w_comp} and 84\% of European households
-% worldwide households have access to at least one computer \cite{itu_hh_w_comp}.
+as well as nearly half of the worldwide households have access to at least one
-% Even 153 years after the first typewriter was patented \cite{noyes_qwerty, }
+computer \cite{eurostat_hous_w_comp, itu_hh_w_comp}. Even 153 years after the
-% people still use keyboards as their main way to input data into a computer
+first typewriter was patented \cite{noyes_qwerty} people still mostly use
-% \parencite[22]{handbook_chi}, \cite{broel_dektop_or_smartphone}. A potential
+identical looking keyboards as their main way to input data into a computer
-% problem while interacting with a computer through the usage of a keyboard are
+\parencite[22]{handbook_chi} \& \cite{broel_dektop_or_smartphone}. A potential
-% rapid movements of the fingers over a prolonged time.
+problem while interacting with a computer through the usage of a keyboard are
+rapid movements of the fingers over a prolonged time, which can cause discomfort
+and increase the risk for \gls{WRUED} \cite{pascarelli_wrued,
+  ccfohas_wrued}. Previous research has shown, that the actuation force, which
+is the force required to generate a keypress, is directly related to the actual
+force an individual generates to press a specific key
+\cite{gerard_keyswitch}. Also, the individual fingers are not capable of
+exerting identical force and therefore fatigue must be higher for weaker fingers
+\cite{bretz_finger, martin_force, baker_kinematics, dickson_finger}. There are
+various designs for alternative keyboards by e.g.,
+Maltron\footnote{\url{https://www.maltron.com/store/c47/Dual_Hand_Keyboards.html}},
+Ergodox\footnote{\url{https://www.ergodox.io/}}, Kenesis
+\footnote{\url{https://kinesis-ergo.com/keyboards/advantage2-keyboard/}},
+etc. which, because of the often unusual layouts and extra keys for the thumbs,
+all require the typist to adjust to a completely new way of typing and therefore
+could reduce productivity during this adjustment phase. Additionally, a study by
+Baker et al. (n = 77) revealed, that even after several months of using a
+keyboard with an alternative design, in terms of usability, participants still
+preferred the traditional design because of its superb usability
+\cite{baker_ergo2}. With these insights, the uniformity of actuation force
+across conventional keyboards may be a potential characteristic that could be
+improved on, to reduce the strain on weaker fingers and thus reduce fatigue and
+increase comfort. Therefore, a keyboard with, per key, adjusted actuation force,
+depending on the finger usually operating the key, might be a feasible solution
+without the requirement for typists to invest in higher priced alternative
+keyboards, which also require additional familiarization. To become a successful
+alternative, the adjusted keyboard design has to perform equally good or even
+better than existing conventional keyboard designs, while also enhancing the user
+experience during usage. These requirements led to the research question of
+this thesis:
 
-% Input tasks are not only restricted to pure data entry but also include complex
+\vspace{1em}
-% inputs required by games.
+\begin{tabular}{p{0.3cm} p{0.5cm} p{13cm} p{0.5cm}}
+  & \textbf{\large RQ}	& {Does an adjusted actuation force per key have a positive impact on efficiency and overall satisfaction while using a mechanical keyboard?} & \\
+\end{tabular}
+\vspace{1em}
 
+If this question could be positively answered, companies producing keyboards
+could implement the proposed adjustments in actuation force into existing
+manufacturing processes and thereby make adjusted keyboard designs broadly
+available and potentially keep the retail prices acceptably low.
 
-% Prolonged usage of computers can lead to serious diseases
 
 
+% This raises the question, if keyboards for
+% personal or work related use cases with adjusted actuation forces per finger or
+% even customizable keyboards, where an individual can select the actuation force
+% for each keyswitch individually.
 
-% With the rising popularity of smartphones and other touchscreen devices
+% Depending on the mechanism and type of key used, it
-% \cite{gs_statcounter_dmt_2020} which utilize virtual keyboards to fulfill a
+% is possible that different force has to be applied to the key to activate
-% variety of tasks that also include data entry, e.g., writing text messages,
+% it. Normally, the force required to activate a key is identical for each key
-% short emails, communicating on social media or web browsing
+% across the keyboard. However, previous research has shown, that there is a
+% disparity in force generated by different fingers
+% \cite{bretz_finger_force}. This raises the question, why there are no keyboards
+% for personal or work related use cases with adjusted actuation forces per finger
+% or even customizable keyboards, where an individual can select the actuation
+% force for each keyswitch individually.
+
+% Input tasks are not only restricted to pure data entry but also include complex
+% inputs required by games.

chap2/literature_review.tex

@@ -554,10 +554,11 @@ been measured in different studies \cite{bretz_finger, martin_force,
   baker_kinematics, dickson_finger}, to our best knowledge, there are no
 measurements concerning the maximum force each individual finger can apply in
 different positions related to a key on the keyboard. Further, during our
-research we only found one manufacturer of keyboards (Realforce), that already
+research we only found one manufacturer of keyboards
-offers models with variable actuation force. These keyboards feature two types
+(Realforce\footnote{\url{https://www.realforce.co.jp/en/products/}}), that
-of keys and require less force towards the edges and more force towards the
+already offers models with variable actuation force. These keyboards feature two
-middle \cite{realforce_topre}. We therefore try to provide a sensible
+types of keys and require less force towards the edges and more force towards
+the middle \cite{realforce_topre}. We therefore try to provide a sensible
 distribution of actuation forces across a non-uniformly equipped keyboard and
 evaluate the possible advantages and disadvantages of such a design to encourage
 other manufacturers to produce similar alternative keyboard designs.

chap3/implementation.tex

@@ -20,7 +20,16 @@ prototype a device that is able to simulate the position of different keyswitche
 and measure the applied force by the finger usually responsible to actuate a
 specific key.
 
-Both implementations are explained in more detail in the following two sections.
+Both implementations are explained in more detail in the following two sections
+as shown in Figure \ref{fig:s3_flow}
+
+\begin{figure}[H]
+  \centering
+  \includegraphics[width=1.0\textwidth]{images/section_3_flow}
+  \caption{Overview of the topics covered in the following sections}
+  \label{fig:s3_flow}
+\end{figure}
+
 \subsection{Typing Test Platform}
 \label{sec:gott}
 The platform we created is called \gls{GoTT} because the backend, which is the
@@ -88,7 +97,7 @@ The platform offers three major functionalities that are important for this thes
 
   \begin{figure}[H]
     \centering
-    \includegraphics[width=1.0\textwidth]{images/gott_text_area.jpg}
+    \includegraphics[width=0.80\textwidth]{images/gott_text_area.jpg}
     \caption{\gls{GoTT}'s typing test. The \textit{START} button reveals the
       text selected with the dropdown menu labeled \textit{Text to
         transcribe}. The \textit{RESET} button interrupts the currently active

chap4/methodology.tex

@@ -20,7 +20,17 @@ hand was able to apply to distinct keys in different locations. We then created
 the design for the adjusted keyboard based on those measurements. Lastly, an
 experiment with twenty-four participants was conducted, where we compared the
 performance and user satisfaction while using four different keyboards,
-including our adjusted keyboard.
+including our adjusted keyboard. Figure \ref{fig:s4_flow} presents a brief
+overview of the consecutive sections.
+
+\begin{figure}[H]
+  \centering
+  \includegraphics[width=1.0\textwidth]{images/section_4_flow}
+  \caption{Overview of the topics covered in the following sections}
+  \label{fig:s4_flow}
+\end{figure}
+
+\pagebreak
 
 \subsection{Preliminary Telephone Interview}
 \label{sec:telephone_interview}
@@ -31,37 +41,44 @@ years and especially the capabilities modern smartphones offer, keyboard usage
 has changed. Further, we wanted to gather information about the preference of
 key resistance, keyswitch type and experiences with \gls{WRUED}. Therefore, we
 conducted a structured interview with seventeen volunteers (59\% females) via
-telephone. The age of the subjects ranged between 22 and 52 with a mean age of
+telephone, from which the most important results are presented in Figure
-29 years. The professions of subjects were distributed among medical workers,
+\ref{fig:res_tel}. The age of the subjects ranged between 22 and 52 with a mean
-students, office employees, computer engineers and community workers. The first
+age of 29 years. The professions of subjects were distributed among medical
-question we asked was \textit{``Which keyboard in terms of actuation force would
+workers, students, office employees, computer engineers and community
-  be the most satisfying for you to use in the long run?''}. Thirteen (76\%) out
+workers. The first question we asked was \textit{``Which keyboard in terms of
-of the seventeen subjects mentioned, that they would prefer a keyboard with
+  actuation force would be the most satisfying for you to use in the long
-light actuation force over a keyboard with higher resistance. The next question
+  run?''}. Thirteen (76\%) out of the seventeen subjects mentioned, that they
-\textit{``Have you ever had pain when using a keyboard and if so, where did you
+would prefer a keyboard with light actuation force over a keyboard with higher
-  have pain?''} yielded, that 41\% of those polled experienced pain at least
+resistance. The next question \textit{``Have you ever had pain when using a
-once while using a keyboard. The areas affected described by the seven who
+  keyboard and if so, where did you have pain?''} yielded, that 41\% of those
-already experienced pain were the wrist \underline{and} forearm (3 out of 7),
+polled experienced pain at least once while using a keyboard. The areas affected
-wrist only (2 out of 7), fingers (1 out of 7) and forearm only (1 out of 7). The
+described by the seven who already experienced pain were the wrist
-results for the third question \textit{``Which keyboard are you currently using
+\underline{and} forearm (3 out of 7), wrist only (2 out of 7), fingers (1 out of
-  and for how many hours a day on average?''} were in line with the statements
+7) and forearm only (1 out of 7). The results for the third question
-we found during our literature review \cite{ergopedia_keyswitch,
+\textit{``Which keyboard are you currently using and for how many hours a day on
-  peery_3d_keyswitch}. Nine answered that they use a notebook (scissor-switches,
+  average?''} were in line with the statements we found during our literature
-membrane), six stated that they use an external keyboard with rubber dome
+review \cite{ergopedia_keyswitch, peery_3d_keyswitch}. Nine answered that they
-switches and only two responded that they use a keyboard featuring mechanical
+use a notebook (scissor-switches, membrane), six stated that they use an
-keyswitches. The average, self-reported, usage ranged between half an hour and
+external keyboard with rubber dome switches and only two responded that they use
-10 hours with a mean of 4.71 hours. It is important to note, that a study by
+a keyboard featuring mechanical keyswitches. The average, self-reported, usage
-Mikkelsen et al. found, that self-reported durations related to computer work
+ranged between half an hour and 10 hours with a mean of 4.71 hours. It is
-can be inaccurate \cite{mikkelsen_duration}. The last question \textit{``Which
+important to note, that a study by Mikkelsen et al. found, that self-reported
-  tasks do you still prefer to perform with a keyboard rather than your mobile
+durations related to computer work can be inaccurate
-  phone?''} revealed, that all of the subjects preferred to use a keyboard when
+\cite{mikkelsen_duration}. The last question \textit{``Which tasks do you still
-entering greater amounts of data (emails, applications, presentations,
+  prefer to perform with a keyboard rather than your mobile phone?''} revealed,
-calculations, research), but also surprisingly 41\% preferred to use a keyboard
+that all of the subjects preferred to use a keyboard when entering greater
-to write instant messages (chatting via Whatsapp
+amounts of data (emails, applications, presentations, calculations, research),
-Web\footnote{\url{https://web.whatsapp.com/}}, Signal
+but also surprisingly 41\% preferred to use a keyboard to write instant messages
+(chatting via Whatsapp Web\footnote{\url{https://web.whatsapp.com/}}, Signal
 Desktop\footnote{\url{https://signal.org/download/}}, Telegram
 Desktop\footnote{\url{https://desktop.telegram.org/}}).
-
+\begin{figure}[H]
+  \centering
+  \includegraphics[width=1.0\textwidth]{images/res_telephone_interview}
+  \caption{Most important results from the preliminary telephone interview}
+  \label{fig:res_tel}
+\end{figure}
+\pagebreak
 \subsection{Market Analysis of Available Mechanical Keyswitches}
 \label{sec:market_forces}
 To gather information about available actuation forces, we collected the product
@@ -451,8 +468,8 @@ with their fingers (dorsal) to the bottom of the table while resting their
 forearms on their thighs (\gls{MVC} - extension). We decided to also measure
 0\%\gls{MVC} before and after each typing test and used these values to
 normalize the final data instead of the 0\%\gls{MVC} we retrieved from the
-initial \gls{MVC} measurements.
+initial \gls{MVC} measurements. A picture of all participants with the attached
-
+electrodes can be observed in Appendix \ref{app:emg}.
 
 \textbf{Familiarization with \glsfirst{GoTT} and the Keyboards}
 

chap6/discussion.tex

@@ -36,10 +36,13 @@ that subjects typed a bit slower (< 3\%) on \textit{Athena (80 g)} compared to
 \textit{Aphrodite (50 g)} and \textit{Hera (35 - 60 g)}. With the differences in
 metrics that are commonly used to measure typing speed more closely related to
 productivity (\gls{WPM}, \gls{AdjWPM}) and the trends that indicate a slight
-difference in operating speed, we can accept our hypothesis that a difference in
+difference in operating speed we could have accepted our hypothesis. However,
-actuation force, at least indirectly, has an impact on typing speed.
+with the relation between error rate and typing speed described in the next
+section and the thereby rather indirect effect of the actuation force, we can
+only partially accept our hypothesis that a difference solely in actuation
+force, has an impact on typing speed.
 
-\begin{phga_hyp*}[1 $\rightarrow$ \cmark]
+\begin{phga_hyp*}[1 $\rightarrow$ \cmark\kern-1.1ex\raisebox{.7ex}{\rotatebox[origin=c]{125}{--}}]
   Actuation force has an impact on typing speed (efficiency - speed).
 \end{phga_hyp*}
 
@@ -200,7 +203,7 @@ those two keyboards \cite{baumeister_bad}.
 
 \begin{figure}[H]
   \centering
-  \includegraphics[width=0.9\textwidth]{images/ratio_interview}
+  \includegraphics[width=0.80\textwidth]{images/ratio_interview}
   \caption{The ration of $\frac{Positive Responses}{Negative Responses}$ during
     the semi-structured interview for all test keyboards}
   \label{fig:ratio_interview}

chap7/conclusion.tex

@@ -1,16 +1,78 @@
 \section{Conclusion}
-\label{sec:label}
+\label{sec:conclusion}
 Since keyboards are still the main data input device while using a computer and
 are also found to be related to discomfort or even \glsfirst{WRUED}
 \cite{pascarelli_wrued}, we tried to evaluate a possible modification to the
 existing keyboard design, that does not require the consumers to extensively
 adapt their typing behaviour, nor the producers to massively deviate from
-existing manufacturing processes. Therefore, we created a keyboard that used
+existing manufacturing processes. To reduce the load on weaker fingers, we
-keyswitches with actuation forces, related to the specific finger the keyswitch
+created a keyboard that used keyswitches with actuation forces, related to the
-is operated with.
+specific finger the keyswitch is operated with and hoped to thereby decrease the
+risk for \gls{WRUED}. The evaluation of the impact of different actuation forces
+on typing speed, error rate and satisfaction revealed, that higher actuation
+forces reduce error rates compared to lower actuation forces and that the typing
+speed is also influenced, \textbf{at least indirectly}, by differences in
+actuation force. Especially the keyboard with very low actuation force,
+\textit{Nyx (35 g)}, which also had the highest average error rate was
+significantly slower than all other keyboards. Therefore, we investigated, if
+there is a connection between high error rates and stagnating typing speed and
+found, that in general, the error rate was a factor for lower input
+rates. Neither the satisfaction nor the muscle activity was significantly
+influenced solely by the actuation.
 
-\subsection{Future work}
+In conclusion, our study showed, that the keyboard with non-uniform actuation
-\label{sec:label}
+forces―\textit{Hera (35 - 60 g)}―was not able to improve the overall typing
+experience significantly enough to supersede existing designs, but was still a
+viable alternative to all traditional keyboards we tested. It could be possible,
+that due to the unconventional force distribution, that similar to keyboards
+with very light actuation force, the muscle activity while using \textit{Hera}
+could decrease when users are given more time to adapt to this keyboard
+\cite{gerard_keyswitch}.  Additionally, we found that keyboards with either very
+high (80 g) or very low (35 g) actuation forces had the most influence on typing
+related metrics, when compared to the more commonly sold keyboards with around
+50 g to 60 g actuation force. In the next sections we identify possible
+limitations and propose some ideas on how to reevaluate custom keyboard designs
+in future studies.
 
 \subsection{Limitations}
-\label{sec:label}
+\label{sec:limitations}
+The first limitation of our study design was the rather short time period of in
+total 10 minutes, for every participant to adjust to each keyboard. With
+prolonged typing session, familiarization, especially for keyboards with lighter
+actuation force, would have been more realistic to a real life scenario where a
+person bought a new keyboard. Furthermore, the laboratory test environment where
+the researcher was in the same room, the limited time for the individual typing
+tests and the rather short breaks in between typing tests, could have influenced
+some subjects by inducing unnecessary stress. Another limitation related to the
+preliminary finger strength study, was the very small number of participants (n
+= 6). Although we measured the finger strengths in different positions for 50\%
+female and male participants, the age distribution was not diverse (M = 24) and
+with a higher number of subjects, the results would have been much more
+reliable. Similarly, the number and diversity in occupation of participants
+could have been higher for our main study (n = 24) to yield even more meaningful
+results. The low number of participants in general was partly due to the ongoing
+COVID-19 pandemic. Lastly, we could have used more linear mixed models during
+our statistical analysis, to be able to make statements about the influence of
+other factors e.g., age, gender, average daily keyboard usage, etc., on speed,
+error rate and satisfaction.
+
+\subsection{Future work}
+\label{sec:fw}
+We propose, that in further research related to keyboards with non-uniform
+actuation force (adjusted keyboards), participants should test several different
+adjusted keyboards and the results should be compared to one identical looking
+keyboard that utilizes a uniform layout of keyswitches with an actuation force
+of 50 g to 65 g. Further, different adjusted layouts, with e.g. higher or lower
+base actuation force than 50 g could be used to calculate the individual spring
+resistances used for each key or a similar layout to the one used in
+Realforce\footnote{\url{https://www.realforce.co.jp/en/products/}} keyboards,
+could be compared to each other. Furthermore, long term studies with adjusted
+keyboards, where participants use the adjusted keyboard for 3 to 4 months and
+then use a uniform keyboard they prefer for another 3 to 4 months as their daily
+driver, could yield more accurate results, due to the chance to fully adapt to
+the individual keyboards. During those months \gls{EMG} and typing related
+metrics should be measured on a regular basis. Lastly, it would be interesting
+to investigate if an adjusted keyboard can reduce pain or at least enhance
+comfort for typists with pre-existing diseases influenced by typing activities
+(disorders of the upper extremity), since one of our participants with a similar
+disease reported a great reduction in pain while using \textit{Hera}.

ref_shelf.bib

@@ -7,10 +7,21 @@
   author =       {Eurostat},
   booktitle =    {Statista},
   url =
-                  {https://www-statista-com.thi.idm.oclc.org/statistics/275306/share-of-enterprises-who-used-computers-in-the-uk-and-eu-since-2010/},
+                  {https://www.statista.com/statistics/275306/share-of-enterprises-who-used-computers-in-the-uk-and-eu-since-2010/},
   year =         2016,
   month =        {may},
-  urldate =      {2020-10-12}
+  urldate =      {2021-07-01}
+}
+
+
+@incollection{eurostat_hous_w_comp,
+  title =        {Households - Availability of Computers},
+  author =       {Eurostat},
+  url =
+                  {https://appsso.eurostat.ec.europa.eu/nui/show.do?dataset=isoc_ci_cm_h&lang=en},
+  year =         2021,
+  month =        {may},
+  urldate =      {2021-07-01}
 }
 
 @incollection{iresearch_ent_w_comp,
@@ -19,22 +30,19 @@
   author =       {iResearch},
   booktitle =    {Statista},
   url =
-                  {https://www-statista-com.thi.idm.oclc.org/statistics/885270/enterprise-computer-usage-rate-in-china/},
+                  {https://www.statista.com/statistics/885270/enterprise-computer-usage-rate-in-china/},
   year =         2018,
   month =        {jul},
-  urldate =      {2020-10-12}
+  urldate =      {2021-07-01}
 }
 
 @incollection{itu_hh_w_comp,
-  title =        {Share of households with a computer at home worldwide from
+  title =        {Key ICT indicators for developed and developing countries, the world and special regions},
-                  2005 to 2019 [Graph]},
   author =       {ITU},
-  booktitle =    {Statista},
   url =
-                  {https://www-statista-com.thi.idm.oclc.org/statistics/748551/worldwide-households-with-computer/},
+                  {https://www.itu.int/en/ITU-D/Statistics/Documents/facts/ITU_regional_global_Key_ICT_indicator_aggregates_Nov_2020.xlsx},
-  year =         2019,
+  year =         2020,
-  month =        {nov},
+  urldate =      {2021-07-01}
-  urldate =      {2020-10-12}
 }
 
 @article{bretz_finger_force,
@@ -88,7 +96,7 @@ urldate = {2021-07-01}
 author = {Stephanie Glen},
 title = {Counterbalancing in Research},
 url = {https://www.statisticshowto.com/counterbalancing-2/},
-urldate = {2020-10-12}
+urldate = {2021-06-12}
 }
 
 @incollection{handbook_chi,
@@ -332,6 +340,17 @@ urldate = {2021-06-28}
   publisher =    {American Occupational Therapy Association}
 }
 
+@article{baker_ergo2,
+  title={The effect of an alternative keyboard on musculoskeletal discomfort: A randomized cross-over trial},
+  author={Baker, Nancy A and Moehling, Krissy K and Park, Seo Young},
+  journal={Work},
+  volume={50},
+  number={4},
+  pages={677--686},
+  year={2015},
+  publisher={IOS Press}
+}
+
 @article{tittiranonda_ergo,
   title={Effect of four computer keyboards in computer users with upper extremity musculoskeletal disorders},
   author={Tittiranonda, Pat and Rempel, David and Armstrong, Thomas and Burastero, Stephen},

thesis.tex

@@ -329,8 +329,8 @@ citecolor=red,
 \cleardoublepage
 
 % Anhänge/Appendices
-% \include{appendices}
+\include{appendices}
-% \cleardoublepage
+\cleardoublepage
 
 % ------------------------------------------------------------------------------------
 % ----------------DOKUMENTENENDE - END OF DOCUMENT------------------------------------