Effects Of Active Cooling Following Simulated Military Work In The Heat

In tilting-pad journal bearings (TPJB) with a non-flooded lubrication concept, higher maximum pad temperatures occur than with a flooded bearing design due to the lower convective heat transfer at the pad edges. In this paper, we present an approach to influence the thermal behavior of a five-pad TPJB by active cooling. The aim of this research is to investigate the influence of additional oil supply grooves at the trailing edge of the two loaded pads on the maximum pad temperature of a large TPJB in non-flooded design. We carry out experimental and numerical investigations for a redesigned test bearing. Within the experimental analysis, the reduction in pad temperature is quantified. A simulation model of the bearing is synthesized with respect to the additional oil supply grooves. The simulation results are compared with the experimental data to derive heat transfer coefficients for the pad surfaces. The experimental results indicate a considerable reduction of the maximum pad temperatures. An overall lower temperature level is observed for the rear pad in circumferential direction (pad 4). The authors attribute this effect by a cooling oil carry-over from the previous pad (3). Within the model limits, a good agreement of the simulation and experimental results can be found.

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Occupational Segregation: Comparing the Civilian and Military Work Force

Armed Forces & Society ◽

10.1177/0095327x9201800304 ◽

1992 ◽

Vol 18 (3) ◽

pp. 363-381 ◽

Cited By ~ 13

Author(s):

Juanita M. Firestone

Keyword(s):

Occupational Segregation ◽

Work Force ◽

Military Work

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Effect of the CMT advanced process combined with an active cooling technique on macro and microstructural aspects of aluminum WAAM

Rapid Prototyping Journal ◽

10.1108/rpj-11-2020-0285 ◽

2021 ◽

Vol ahead-of-print (ahead-of-print) ◽

Author(s):

Felipe Ribeiro Teixeira ◽

Fernando Matos Scotti ◽

Ruham Pablo Reis ◽

Américo Scotti

Keyword(s):

Electrical Signal ◽

Management Technique ◽

Marginal Effect ◽

Thin Wall ◽

Cold Metal Transfer ◽

Content Type ◽

Active Cooling ◽

Cold Metal ◽

Wire Arc Additive Manufacturing ◽

Cooling Technique

Purpose This paper aims to assess the combined effect of the Cold Metal Transfer (CMT) advanced process and of a thermal management technique (near immersion active cooling [NIAC]) on the macro and microstructure of Al wall-like preforms built by wire arc additive manufacturing (WAAM). As specific objective, it sought to provide information on the effects of the electrode-positive/electrode-negative (EP/EN) parameter in the CMT advanced process fundamental characteristics. Design/methodology/approach Initially, bead-on-plate deposits were produced with different EP/EN ratios, still keeping the same deposition rate, and the outcomes on the electrical signal traces and bead formation were analyzed. In a second stage, the EP/EN parameter and the layer edge to water distance (LEWD) parameter from the NIAC technique were systematically varied and the resultant macro and microstructures compared with those formed by applying natural cooling. Findings Constraints of EP/EN setting range were uncovered and discussed. The use of the NIAC technique favors the formation of finer grains. For a given EP/EN value, a variation in the NIAC intensity (LEWD value) showed marginal effect on grain size. When the EP/EN parameter effect is isolated, i.e. for a given LEWD setting, it was observed that an increase in the EP/EN level favors coarser grains. Originality/value Both the EP/EN parameter and the use of an active cooling technique (NIAC) might be used, even in combination, as effective tools for achieving proper macro and microstructure in WAAM of thin wall builds.

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The Impact of Military Work Experience on Later Hiring Chances in the Civilian Labour Market. Evidence from a Field Experiment

Economics The Open-Access Open-Assessment E-Journal ◽

10.5018/economics-ejournal.ja.2013-37 ◽

2013 ◽

Vol 7 (2013-37) ◽

pp. 1 ◽

Cited By ~ 2

Author(s):

Stijn Baert ◽

Pieter Balcaen

Keyword(s):

Field Experiment ◽

Labour Market ◽

Work Experience ◽

The Impact ◽

Military Work

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Association between active cooling and lower mortality among patients with heat stroke and heat exhaustion

PLoS ONE ◽

10.1371/journal.pone.0259441 ◽

2021 ◽

Vol 16 (11) ◽

pp. e0259441

Author(s):

Jun Kanda ◽

Shinji Nakahara ◽

Shunsuke Nakamura ◽

Yasufumi Miyake ◽

Keiki Shimizu ◽

...

Keyword(s):

Hospital Mortality ◽

Core Body Temperature ◽

Heat Stroke ◽

Case Series ◽

Clinical Findings ◽

Hospital Death ◽

Heat Illness ◽

Heat Exhaustion ◽

Active Cooling ◽

Severe Group

Body cooling is recommended for patients with heat stroke and heat exhaustion. However, differences in the outcomes of patients who do or do not receive active cooling therapy have not been determined. The best available evidence supporting active cooling is based on a case series without comparison groups; thus, the effectiveness of this method in improving patient prognoses cannot be appropriately quantified. Therefore, we compared the outcomes of heat stroke patients receiving active cooling with those of patients receiving rehydration-only therapy. This prospective observational multicenter registry-based study of heat stroke and heat exhaustion patients was conducted in Japan from 2010 to 2019. The patients were stratified into the “severe” group or the “mild-to-moderate” group, per clinical findings on admission. After conducting multivariate logistic regression analyses, we compared the prognoses between patients who received “active cooling + rehydration” and patients who received “rehydration only,” with in-hospital death as the endpoint. Sex, age, onset situation (i.e., exertional or non-exertional), core body temperature, liver damage, renal dysfunction, and disseminated intravascular coagulation were considered potential covariates. Among those who received active cooling and rehydration-only therapy, the in-hospital mortality rates were 21.5% and 35.5%, respectively, for severe patients (n = 231) and 3.9% and 5.7%, respectively, for mild-to-moderate patients (n = 578). Rehydration-only therapy was associated with a higher in-hospital mortality in patients with severe heat illness (adjusted odds ratio [aOR], 3.29; 95% confidence interval [CI], 1.21–8.90), whereas the cooling methods were not associated with lower in-hospital mortality in patients with mild-to-moderate heat illness (aOR, 2.22; 95% CI, 0.92–5.84). Active cooling was associated with lower in-hospital mortality only in the severe group. Our results indicated that active cooling should be recommended as an adjunct to rehydration-only therapy for patients with severe heat illness.

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