7 research outputs found
신체적 부하가 작업기억 과업 수행능력에 미치는 영향
Get PDF학위논문 (박사)-- 서울대학교 대학원 : 공과대학 산업공학과, 2018. 2. 박우진.Many workers, including soldiers, firefighters, and policemen, perform demanding physical work tasks while carrying heavy equipment. For example, soldiers carry around 30-50kg of military gear and perform prolonged standing and marching, and many other postural and movement tasks. The occupational activities of the workers carrying extra weights are not limited to physical tasks. They also perform various mental tasks along with physical ones – the mental and physical tasks are conducted close in time and often simultaneously. For example, in the case of soldiers, the mental tasks include comprehending dynamic battlefield situations, communicating information, making decisions, issuing and receiving operational orders, etc.
In a similar context, workers in the medical field such as doctors, nurses, and pharmacists frequently multitask and are faced with physical workload in addition to their high level of mental workload. For example, nurses are required to complete physical tasks such as lifting patients for transfer out of bed and from the floor, while completing mental tasks, all in an urgent and busy work environment.
As mentioned above, many human work tasks consist of a physical component (physical sub-tasks) and a mental component (mental sub-tasks) – rarely are there work tasks that only requires the use of one component. Therefore, workers tend to experience both physical and mental workload while completing their work task.
From the human information processing (HIP) point of view, physical and mental tasks constituting a work activity are thought to be mutually influential rather than independent. Indeed, such mutual relationships have been empirically demonstrated in many previous studies. The previous results on the inter-relationship between the concurrent physical and mental tasks lead to the hypothesis that the body-worn equipment weight or postural loading affects the performance of some of their mental tasks. Understanding how the body-worn equipment weight or postural loading affects the performance of different mental tasks will provide a basis for designing work tasks to maximize safety, performance and worker wellbeing. Despite the significance, however, few studies seem to have examined such relationships.
Therefore, this study aimed to empirically investigate the effects of body-worn equipment weight or postural loading on a workers performance of basic working memory tasks while the worker is simultaneously performing a certain physical task. To accomplish these objectives, two major studies were conducted.
In study 1, the effects of body-worn equipment weight on the performance of basic working memory tasks were examined. A backpack was adopted as a representative piece of body-worn equipment as it is widely used among workers, including soldiers and firefighters. Three types of physical tasks were considered in this study. They were flat-surface standing, walking along a predetermined route, and walking along a straight route, which are representative physical tasks performed by various workers including soldiers and firefighters. Also, three types of working memory tasks were considered so as to examine the different sub-components of the working memory system, that is, the visuo-spatial sketchpad, phonological loop and central executive systems. The results of data analyses showed that backpack weight affected working memory task scores differently in regards to the type of working memory task and physical task. Overall, working memory task scores had a tendency to decrease as backpack weight increased.
In study 2, the effects of postural loading on the performance of basic working memory tasks were investigated. In the case of the physical task, a specific posture was held for a predetermined amount of time, and four posture groups were considered, each with a different amount of postural loading. Three types of working memory tasks were considered as in study 1. The data analyses revealed significant effects of postural loading on the scores of the working memory tasks. As postural loading increased, all of the three working memory task scores decreased.
The study findings entail that reducing the body-worn equipment weight or postural loading can positively impact the worker's mental task performance in addition to reducing the worker's bodily stresses and the risks of work-related musculoskeletal disorders. This is especially important for situations where workers perform critical mental tasks along with demanding physical tasks, as in the work activities of soldiers, firefighters, pilots and medical team. Such results may contribute to the practical design of products or systems which require multitasking, by providing an experimental basis about the increased mental performance when using such products (or reducing the decrease of mental performance). Such results also provide empirical evidence about possible improvements for work tasks where multitasking of physical and mental tasks occurthis may be in the form of work station design or working posture improvement.Chapter 1. Introduction 1
1.1 Research background 1
1.2 Research objectives 4
1.3 Dissertation outline 6
Chapter 2. Related literature 9
2.1 Physical workload and mental task performance 9
2.2 Postural loading and mental task performance 11
2.3 Working memory 13
Chapter 3. Body-worn equipment weight and working memory task performance 15
3.1 Background 15
3.2 Overview 18
3.3 Standing task 20
3.3.1 Method 20
3.3.2 Results 30
3.3.3 Discussion 38
3.4 Navigating task 48
3.4.1 Method 48
3.4.2 Results 56
3.4.3 Discussion 63
3.5 Standing, navigating and walking tasks 71
3.5.1 Method 71
3.5.2 Results 78
3.5.3 Discussion 94
3.6 Modeling the effect of backpack weight on working memory task performance distribution 100
3.6.1 Standing task 101
3.6.2 Navigating task 103
3.6.3 Walking task 105
3.6.4 Discussion 107
Chapter 4. Postural loading and working memory task performance 109
4.1 Background 109
4.2 Overview 112
4.3 Method 113
4.3.1 Participants 113
4.3.2 Experimental tasks 114
4.3.3 Procedures and dependent measures 117
4.3.4 Data analyses 121
4.4 Results 122
4.4.1 Working memory task scores 122
4.4.2 Postural sway measures 124
4.4.3 Heart rate 127
4.4.4 Physical discomfort and mental workload 128
4.5 Discussion 130
Chapter 5. Conclusion 139
5.1 Summary 139
5.2 Implications of the research 141
5.3 Limitations and future works 144
Bibliography 146
Appendix A. The ANOVA table for standing task 167
Appendix B. The ANOVA table for navigating task 191
Appendix C. Two-way ANOVA table 211
Appendix D. The ANOVA table for postural holding 223
Appendix E. The Corsi block task 247
Appendix F. The digit span task 250
Appendix G. The 3-back task 251
Abstract (in Korean) 253Docto
제스처 기반의 인간-기계 인터렉션을 위한 수화동작의 사용성 평가
No full text학위논문 (석사)-- 서울대학교 대학원 : 산업공학과, 2014. 2. 박우진.Utilizing gestures of major sign languages (signs) for gesture-based interaction seems to be an appealing idea as it has some obvious advantages, including: reduced time and cost for gesture vocabulary design, immediate accommodation of existing sign language users and supporting universal design and equality by design. However, it is not well understood whether or not sign language gestures are indeed adequate for gesture-based interaction, especially in terms of usability. As an initial effort to enhance our understanding of the usability of sign language gestures, the current study evaluated Korean Sign Language (KSL) gestures employing three usability criteria: intuitiveness, preference and physical stress. A set of 18 commands for manipulating objects in virtual worlds was determined. Then, gestures for the commands were designed using two design methods: the sign language method and the user design method. The sign language method consisted of simply identifying the KSL gestures corresponding to the commands. The user design method involved having user representatives freely design gestures for the commands. A group of evaluators evaluated the resulting sign language and user-designed gestures in intuitiveness and preference through subjective ratings. Physical stresses of the gestures were quantified using an index developed based on Rapid Upper Limb Assessment. The usability scores of the KSL gestures were compared with those of the user-designed gestures for relative evaluation. Data analyses indicated that overall, the use of the KSL gestures cannot be regarded as an excellent design strategy when viewed strictly from a usability standpoint, and the user-design approach would likely produce more usable gestures than the sign language approach if design optimization is performed using a large set of user-designed gestures. Based on the study findings, some gesture vocabulary design strategies utilizing sign language gestures are discussed. The study findings may inform future gesture vocabulary design efforts.1. INTRODUCTION 1
1.1 Background 1
1.2 Objectives 5
2. METHOD 7
2.1 Determining a set of commands for virtual object
manipulation (step 1)8
2.2 Creating gestures for expressing commands (step 2) 10
2.3 Evaluating gestures using usability measures (step 3)11
2.4 Data processing and analyses (step 4)17
3. RESULTS 18
4. DISCUSSION 31
5. CONCLUSION 37
REFERENCES 40
APPENDIX : Usability evaluation form 44
ABSTRACT 57Maste
얼굴 영상 분석을 위한 다중 모달 딥러닝 모델 연구
No full text사람의 얼굴을 분석하면 신원을 특정하거나 기분, 상태를 확인 할 수 있다. 컴퓨터 비전 분야에서는 영상 내의 얼굴을 분석하기 위해 얼굴 영역을 분할하는 딥러닝 기반의 기법들이 지속적으로 연구되고 있다. 최근에는 디지털 휴먼 생성 기술이 주목 받으면서, 얼굴 영역 분할, 깊이, 법선 벡터 등의 정보를 분석하는 기반 기술의 수요가 증가하고 있다. 이에 따라 앞서 언급된 다중 모달정보를 분석하는 기법들이 제안되고있다.
본고에서는 디지털 휴먼 기술 발전에 따른 얼굴 영상 분석 기술의 수요에 맞추어 얼굴 영상에서 여러 분석 정보를 추출하는 새로운 다중 모달 딥러닝 모델을 제안한다. 제안 모델은 실시간으로 얼굴 영상을 분석할 수 있는 속도를 가지면서, 얼굴 영상 분석 정확도(mIoU) 측면에서 높은 성능을 보인다.
Simulation of Coastal Flood due to Tide-Surge-Storm Water during Typhoon Megi(TY0415) at Yonwon in Busan New harbor Construction Site
No full text태풍 매기가 2004년도에 부산지역에 래습하였다. 이로 인해 건설 중인 부산신항만 내의 용원 지역 해안이 침수되었는데 이의 원인과 영향을 수치실험을 통해 분석하였다. 결과로는 해일이 주 원인이며 대조기시의 평균 조위시에 발생하여 약 최고위 정도로 수면이 상승하였다. 홍수위는 저조위를 2-3cm정도 상승시키는 효과를 나타내었음.1
