基於溝通私密性的考量，使用者通常會選擇以手機收發簡訊或電子郵件方式進行溝通。正因如此，社會上也開始發現許多相關的文明病徵，如: 重覆性使力傷害（Repetitive Strain Injury, RSI）及累積性創傷症候群（Cumulative Trauma Disorders, CTD）。於是乎，讓人們減少拇指工作負荷從而避免傷害亦是刻不容緩的議題，不論是上述何種症狀，確也代表重覆操作同一動作將促使該些病徵擴大之主因。
本研究目標為改善拇指於單手操作介面之工作負荷，更為了因應人們規律地操作同一介面所產生的骨骼肌肉不適症或傷害，遂藉此往下開展子目標。1.改善拇指動作，必須去瞭解拇指之動作限制與拇指評估之特徵，做為改善拇指工作負荷之立論基礎。2.握持姿勢探討，從往常習知的握持姿勢與手掌尺寸，應當能瞭解較為減輕和/或較為吃力之工作負荷姿勢，期望藉此能改善單手操作工作負荷。3. 輸入裝置研究，瞭解輸入裝置之誤觸要因及拇指工作負荷之特徵點，進而避免操作或行進間所可能發生的問題點。研究方法將以上述萃取出較符合單手操作介面之特性因子加以整合並招募相關測試人員進行疲勞度及滿意度之評估。
本研究成果歸納如下。其一、新型介面已可將拇指工作負荷順利轉移至中指及食指，同時並無顯著地疲勞現象產生。其二、藉由滿意度調查結果，所設計之食指及中指操作區域應可滿足單手操作介面之使用需求。
最後，研究結果也顯示握持區域設計及避免拇指誤特徵皆不太能符合受試者之手掌和拇指運動需求。上述三指動作已能改善現有拇指於單手操作介面之工作負荷，期望未來能進一步探討並提昇受試者對於拇指誤觸特徵與手掌握持區域於新型介面之滿意度，更就慣用手及非慣用手之單手操作介面做進一步評估，俾利於提昇單手操作介面之廣度與深度，進而改善使用者之工作負荷。

Normally, the user preferring to choose the E-mail or text message to contact with the others base on the concern of communicated privacy. And there were the lots of modern disease have been founded them in the society. For examples, both the Repetitive Strain Injury and the Cumulative Trauma Disorders were belonging to the modern disease. Thus, it was the urgently topic that can be reducing the thumb workload and preventing the injury on the user. No matter what kind of symptom is, the main factor will be the repetitive actions.
The research subject was improving the thumb workload on the single hand operated interface. Also it can be preventing the musculoskeletal disorder or injury for the regularly using. 1. Improving the thumb movement. We must be realizing the limitation of thumb movement and the feature of thumb evaluation. 2. The study of holding gesture. As the conventional holding gesture and the palm size, the lightly and/or heavily gesture will be realized in easily. 3. The study of input device was realized the feature of thumb workload and the factors of mis-touching for preventing the potential concerns during the movement. As above, the factors of singer hand operated interface were be integrated and recruited the participator for the evaluation of fatigue and satisfaction.
According to the experiment results, there were two suggestions as below. First of all, the fatigue issue did not happen on the thumb. Also the workload has been transferred on the index finger and middle finger. Second of all, it was the questionnaire results of new interface. In advantage, it should be satisfying with the user demand on the singer hand operated interface. In disadvantage, both of the holding area and preventing mis-touch feature cannot be fitting with the palm curve and the demand of thumb movement.
These fingers have been improved the workload of thumb on the singer hand operated interface. Hopefully, the study can move the directions as follow. One of them, the satisfactions of holding area and mis-touch feature will be increasing as well. In the others, the operated interface of dominated and non-dominated hand will be the good topic for the future study. Considering above the directions, they not only can enlarge the scope and the profundity, but also can improve the user workload as well.

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