Objective Measurement Methods of Motion Artifacts for 45-Mbit, NTSC, DPCM, Bit-Reduction Video Codecs

Introduction: The determination of adequate reduction is difficult perioperatively due to inadequate radiographic scanning and objective measurement methods. The purpose of the present study is to evaluate an objective measurement of the weight bearing acetabular dome congruency. The sensitivity and specificity of 2 measurement methods after acetabular fracture fixation are compared. Patients and methods: Postoperative acetabular reduction was assessed based on postoperative anteroposterior radiographs according to hip joint congruency and Matta’s classification in 55 patients. For hip joint congruency measurements, one circle was drawn as superior femoral head border and another one was drawn as weight-bearing acetabular dome border. The difference between the centres of the circles was measured in millimetres. Comparative studies were performed between groups according to reduction quality and clinical and radiological results. Results: The threshold value for the difference between the 2 circle centres was found as 4.4 mm according to the clinical outcomes; 3.8 mm according to radiological outcomes in joint congruency method. The sensitivity of this method was found as 90.2% and 92.7%, and specificity as 64.3% and 57.1% considering the clinical and radiological results, respectively. In the assessment of joint congruency, false positive rate was lower than assessing reduction quality using the method defined by Matta. Conclusions: Joint congruency assessment based on a postoperative anteroposterior radiograph in patients treated with open reduction internal fixation for acetabular fractures is a suitable method for assessing the adequacy of reduction. This method can be used intraoperatively using fluoroscopy imaging during surgery.

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Evaluation of Human Factors for the Next-Generation Displays: A Review of Subjective and Objective Measurement Methods

Journal of the Ergonomics Society of Korea ◽

10.5143/jesk.2013.32.2.207 ◽

2013 ◽

Vol 32 (2) ◽

pp. 207-215 ◽

Cited By ~ 2

Author(s):

Sungchul Mun ◽

Min-Chul Park

Keyword(s):

Human Factors ◽

Measurement Methods ◽

Objective Measurement ◽

Next Generation

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Measurement Methods of Fatigue, Sleepiness, and Sleep Behaviour Aboard Ships: A Systematic Review

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph19010120 ◽

2021 ◽

Vol 19 (1) ◽

pp. 120

Author(s):

Fiona Kerkamm ◽

Dorothee Dengler ◽

Matthias Eichler ◽

Danuta Materzok-Köppen ◽

Lukas Belz ◽

...

Keyword(s):

Systematic Review ◽

Subjective Assessment ◽

Measurement Methods ◽

Objective Measurement ◽

Stress Factors ◽

Sleep Behaviour ◽

Frequent Use ◽

Pubmed Database ◽

Related Stress ◽

Job Related Stress

Since seafarers are known to be exposed to numerous job-related stress factors that can cause fatigue, sleepiness, and disturbed sleep behaviour, the aim of this review was to provide an overview of the subjective and objective measurement methods of these strains. Using a systematic review, 166 studies were identified within the period of January 2010 to December 2020 using the PubMed database. Of the 21 studies selected, 13 used both subjective and objective measurement methods. Six studies used only subjective and two studies only objective methods. For subjective assessment, 12 different questionnaires could be identified as well as activity and sleeping logs. Actigraphy and reaction time tests (RTT) were the most common objective methods. In single cases, electrooculography (EOG), pupillometry and ambulatory polysomnography (PSG) were used. Measurement-related limitations due to vessel-related impacts were less often reported than expected. No restrictions of daily routines on board were described, and only single-measurement disturbances due to ship movements were mentioned. The present literature review reveals that there are various routines to measure fatigue, sleepiness, and sleep behaviour on board. A combination of subjective and objective methods often appears to be beneficial. The frequent use of actigraphy and RTT on board suggests good feasibility and reliable measurements with these methods. The use of ambulatory PSG in maritime-like contexts suggests that this method would also be feasible on board.

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