Publications by authors named "Scott N Mackinnon"

The current industrial environment relies heavily on maritime transportation. Despite the continuous technological advances for the development of innovative safety software and hardware systems, there is a consistent gap in the scientific literature regarding the objective evaluation of the performance of maritime operators. The human factor is profoundly affected by changes in human performance or psychological state.

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Objective: The purpose of this study was to examine how intensity of wave motions affects the performance of a simulated maritime search and rescue (SAR) task.

Background: Maritime SAR is a critical maritime occupation; however, the effect of wave motion intensity on worker performance is unknown.

Methods: Twenty-four participants (12 male, 12 female) performed a simulated search and rescue task on a six-degree-of-freedom motion platform in two conditions that differed in motion intensity (low and high).

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Background: Previous research suggests motion induced fatigue contributes to significant performance degradation and is likely related to a higher incidence of accidents and injuries. However, the exact effect of continuous multidirectional platform perturbations on energy cost (EC) with experienced personnel on boats and other seafaring vessels remains unknown.

Objective: The objective of this experiment was to measure the metabolic ECs associated with maintaining postural stability in a motion-rich environment.

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Computer-aided solutions are essential for naval architects to manage and optimize technical complexities when developing a ship's design. Although there are an array of software solutions aimed to optimize the human element in design, practical ergonomics methodologies and technological solutions have struggled to gain widespread application in ship design processes. This paper explores how a new ergonomics technology is perceived by naval architecture students using a mixed-methods framework.

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Introduction: Given the effects of cold water immersion on breath-hold (BH) capabilities, a practical training exercise was developed for military/paramilitary personnel completing a helicopter underwater egress training (HUET) program. The exercise was designed to provide firsth and experience of the effects of cold water exposure on BH time.

Methods: After completing the required HUET, 47 subjects completed two BH testing sessions as well as a short questionnaire.

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Unlabelled: The effects of long duration simulated motion on motor task and neuromuscular performance along with time frames required to recover from these effects are relatively unknown. This study aimed to determine (1) how simulated motion affects motor task and neuromuscular performance over one hour of motion and (2) the time course of recovery from any decrements. The dependent variables that were measured included: reaction time; visuomotor accuracy tracking; maximal voluntary contractions; voluntary activation; evoked contractile properties and biceps brachii electromyography of the elbow flexors.

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The purpose of this study was to examine how wave-induced platform motion effects postural stability when handling loads. Twelve participants (9 male, 3 female) performed a sagittal lifting/lowering task with a 10 kg load in different sea conditions off the coast of Halifax, Nova Scotia, Canada. Trunk kinematics and foot center of force were measured using the Lumbar Motion Monitor and F-Scan foot pressure system respectively.

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This case study reviews the knowledge transfer (KT) process of implementing a knife sharpening and steeling program into a poultry processing plant via a participatory ergonomics intervention. This ergonomics intervention required stakeholder participation at the company level to move a 'train-the-trainer' program, developed in Québec, Canada, into action on the plant's deboning line. Communications and exchanges with key stakeholders, as well as changes in steeling and production behaviours were recorded.

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Seafaring occupations have been shown to place operators at an increased risk for injury. The purpose of this study was to understand better the demands of a moving environment on the ability of a person to perform specific lifting tasks. Subjects lifted a 15-kg load under four different lifting conditions.

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Maximal voluntary isometric activations (MVIA) are frequently used as inputs for models attempting to predict muscle force and as normalization values in studies assessing muscle function. However, pain may adversely affect maximal muscle activation. The purpose of this study was to assess reliability of MVIA force and electromyographic (EMG) activity during prone isometric back extension in subjects with and without low back pain (LBP).

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Studies employing modified Biering-Sørenson tests have reported that low back endurance is related to the potential for developing low back pain. Understanding the manner in which spinal musculature fatigues in people with and without LBP is necessary to gain insight into the sensitivity of the modified Biering-Sørenson test to differentiate back health. Twenty male volunteers were divided into a LBP group of subjects with current subacute or a history of LBP that limited their activity (n = 10) and a control group (n = 10).

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The flexion-relaxation phenomenon consisting of an erector spinae silent period occurring with trunk flexion can place considerable stress upon tissues. Since individuals often flex their trunks while unstable, the purpose of the study was to examine the effect of an unstable base on the flexion-relaxation response. Fourteen participants flexed at the hips and back while standing on a stable floor or an unstable dyna-disc.

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Introduction: Vehicle motion characteristics differ between air, road, and sea environments, both vestibularly and visually. Effects of vision on motion sickness have been studied before, though less systematically in a naval setting. It is hypothesized that appropriate visual information on self-motion is beneficial in a naval setting and that task performance is likely reduced as sickness increases.

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The purpose of this cross-sectional study was to evaluate the effect of unstable and unilateral resistance exercises on trunk muscle activation. Eleven subjects (6 men and 5 women) between 20 and 45 years of age participated. Six trunk exercises, as well as unilateral and bilateral shoulder and chest presses against resistance, were performed on stable (bench) and unstable (Swiss ball) bases.

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This study examined how experimentally controlled foot positions could affect the temporal and spatial parameters of a load (20% of subject mass) during a one-handed repetitive submaximal pulling activity. Foot positions standardized relative to a frontal and sagittal plane defining a pull force vector were derived based on the preferences of 45 volunteer subjects. In general, the subjects assumed asymmetrical foot positions and on average the big toe of the foot contralateral to the hand exerting the pull was located 19% (SD = 4.

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