通用作戰符號介面之人員績效評估

Assessment on the Human Performance for the Use of Common Warfighting Symbology Interface

曾楓億(Feng-Yi Tseng)

指導教授 ： 黃雪玲

國立清華大學/工學院/工業工程與工程管理學系/博士(2012年)

摘要

伴隨著電腦科技進步，人們依賴電腦執行與工作相關的作業已經越來越廣泛了，其中在國防工業中的軍事調度之電腦應用成長迅速(例如：軍用之雷達系統與地理情報系統)。在戰情室裡，作業人員必須在極短的時間內進行資料分析、評估與決策，而且每個決定都有可能攸關戰場士兵的生死存亡，因此人員的作業績效是可能受到時間與壓力負荷所影響，導致系統介面設計的好壞，對於降低人員工作負荷與預防安全相關的意外，形成一個極重要的因素。
本研究由三個實驗所組成，主要係調查通用作戰符號應用之人機介面設計對人員績效與認知負荷之影響。其中第一個實驗是調查作業人員在視覺終端機上的色彩辨識能力，該能力可能會受到燈光顏色、環境照度與螢幕顯示之背景色所影響。本實驗採用2 × 3 × 3受測者內之全因子實驗設計，自變數為三種燈光顏色(紅光、藍光與白光)、兩種環境照度(50 lux與300 lux)與三種螢幕背景色(黑色、藍色與褐色)。因變數為色彩辨識能力(用Munsell Hue test的誤差分數量化呈現)、完成時間與受測者主觀偏好。結果顯示燈光顏色與螢幕背景色都顯著的影響人員色彩辨識能力(p < 0.01)。該研究結果可以被使用在戰情室中燈光顏色與螢幕背景顏色之設計使用。
第二個實驗內容主要是調查作業人員在視覺終端機上的通用作戰符號視覺搜尋績效。過去研究指出，視覺搜尋績效可能受到目標大小、背景型態與螢幕尺寸影響，尤其當作業人員在戰情室中執行搜尋作業並且有時間壓力時，視覺搜尋績效變的更為重要。本研究共邀請三十六位受測者參與實驗，並採用三因子混合實驗設計，其中自變數為三種螢幕尺寸(7, 15 與 21 英吋，各有三分之一的受測者隨機分配至一種螢幕尺寸進行實驗)，五種圖像尺寸(40, 50, 60, 70與80弧分)與兩種背景形態(有地形與無地形)。螢幕尺寸是受測者間因子，圖像尺寸與背景形態是受測者內因子。因變數為完成時間、正確率、凝視時間、凝視次數與跳視幅度。實驗結果顯示最佳的圖像尺寸80至70弧分，在搜尋作業，21英吋螢幕被選為最佳的螢幕大小，而無地形的背景形態相較於有地形正確率較高。該研究結果可以用來提升戰情室作業人員的視覺搜尋績效，並可應用在戰情室的設計上。
第三個實驗係延伸實驗一與實驗二至地理情報系統中，該研究的目標係藉由膚電反應及瞳孔大小之生理反應量測，用以調查模擬之地理情報系統對於作業人員認知負荷之影響。本研究檢驗地理情報系統之圖像形態(實心與空心)、圖像尺寸(40，60與80弧分)與地圖背景形態(有地形與無地形)對於作業人員之影響，並藉由實驗引領去探索人員在視覺過程中的負荷。結果顯示受測者於目標與背景對比較為明顯時，其認知負荷較低，並且當搜尋空心圖像於無地形顯示的地圖時，搜尋效率較佳。本研究結果可以提供設計者發展更有效率與舒適之介面，以符合使用者需求與給予之設計推薦。

關鍵字

人員色彩辨識 ； 視覺搜尋績效 ； 眼球追蹤 ； 地理情報系統 ； 膚電反應

並列摘要

Human reliance on computers to execute job-related tasks has increased immensely with advances in computer technology. One application of computers that is growing rapidly is performing military maneuvers in defense industries such as radar systems or geographical intelligence systems. In a military information station, operators have to carry out data analysis, assessment, and decision-making in a short time. Each decision which may be decided in milliseconds is a matter of life and death for soldiers. Therefore, the operators’ task performance is affected by stress and time load. This makes the interface of the systems to be one of the most important factors for reducing the human’s cognitive load of preventing safety-related accidents.
This study conducted three experiments to investigate the common warfighting symbology interface design on human performance and cognitive load. The first experiment investigated the human performance on color discrimination in visual display terminals. It may be affected by illuminant colors, the level of ambient illumination and background colors of the monitor. A complete factorial (2 × 3 × 3) within-subject design was used. The independent variables were three illuminant colors (red, blue, and white), two ambient illumination levels (50 lux and 300 lux), and three background colors (black, blue and brown); the three dependent variables were the color discrimination ability (error scores), completion time and subject preference. The results showed that the illuminant colors and the screen background colors both significantly influenced human color discrimination ability (p < 0.01). The result of this research can be used in control room design when considering the effect of color.
The second experiment investigated the visual search performance in visual display terminals. Visual search performance may be affected by target size, background type and the dimensions of the screen. Especially, when there is time pressure for operators to execute the search task in a military information station, visual search performance becomes more important. Thirty-six participants were recruited and a three-factor mixed design was used in which the independent variables were three screen dimensions (7, 15 and 21 inches), five icon sizes (visual angle 40, 50, 60, 70 and 80 min of arc) and two map background clutter types (topography displayed [TD] and topography not displayed [TND]). The five dependent variables were completion time, accuracy, fixation duration, fixation count and saccade amplitude. The results showed that the best icon sizes were 80 and 70 min. The 21 inches screen dimension was chosen as the superior screen for search tasks. The TND map background produced higher accuracy compared to that of TD background. The results of this research can be used in control room design to promote operators’ visual search performance.
The third experiment extended the first and the second experiments to a simulated geographical intelligence system. The objective of this research was to investigate the influence of a simulated geographical intelligence system on operators’ cognitive load by galvanic skin response (GSR) and pupil diameter measures. The experiment was to examine the influence of operators on icon types (hollow and filled), icon sizes (visual angle 40, 60, and 80 min of arc) and map background clutters (TD and TND) in the geographical intelligence system (GIS). The results showed that operators’ cognitive load was lower under higher target/background difference. The search efficiency was well when hollow icons were presented on TND map background. The findings of this study can help the designers to develop more efficient and comfortable interfaces to fit users. Finally, some design specifications were recommended.

並列關鍵字

human color discrimination ； visual search performance ； eye tracking ； geographical intelligence system ； galvanic skin response

參考文獻

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