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Policing requires atypical work hours. The present study examined associations between shiftwork and pregnancy loss among female police officers.

Participants were 91 female officers with a prior history of at least one pregnancy. Shiftwork information was assessed using daily electronic payroll work records. Any prior pregnancy loss (due to miscarriage) was self-reported. Logistic regression estimated odds ratios (OR) and 95% confidence intervals (CI) for main associations.

On average, the officers were 42 years old, had 14 years of service, and 56% reported a prior pregnancy loss. Officers who worked dominantly on the afternoon or night shift during their career had 96% greater odds of pregnancy loss compared to those on day shift (OR = 1.96, 95% CI:0.71–5.42), but the result was not statistically significant. A 25% increase in percent of hours worked on night shift was associated with 87% increased odds of pregnancy loss (OR = 1.87, 95% CI:1.01–3.47). Associations were adjusted for demographic and lifestyle factors. Objective assessment of shiftwork via electronic records strengthened the study. Limitations include small sample size, cross-sectional design and lack of details on pregnancy loss or the timing of pregnancy loss with regard to shiftwork.

The present study is preliminary and cross-sectional.

With considerable further inquiry and findings into this topic, results may have an impact on police policy affecting shift work and pregnant police officers.

Implication on the health and welfare of police officers.

To our knowledge, there are no empirical studies which associate shiftwork and pregnancy loss among police officers. This preliminary study suggested an association between shiftwork and increased odds of pregnancy loss and points out the need for further study.

Industry loss index‐based risk transfer and management instruments such as the industry loss warranty (ILW) and other catastrophe insurance derivative products have proliferated in recent years. This article introduces an alternative measure of the ILW basis risk, specifically the conditional probability that the ILW policy does not pay out, given an actual loss sustained by the policyholder that exceeds some critical level. The author also discusses the effectiveness of upwardly oriented basis risk in reducing loss volatility. After introducing guidelines for choosing between an ILW and traditional reinsurance, the article concludes that a properly structured ILW can be an effective and innovative instrument for a large insurer or reinsurer to manage the severity and volatility of catastrophe losses, but not necessarily, for a medium‐sized or small (re)insurer. Although this article focuses on ILWs, the general methodology and conclusions presented are applicable to other index‐based risk transfer products.

The specific iron losses of amorphous alloy material are extremely low compared with silicon steel material. The iron losses of motors may reduce by replacing the silicon steel core with an amorphous alloy core. However, one drawback of amorphous alloy material is that the specific iron losses will increase a lot after the motor manufacturing process. This paper aims to study the influences of interlaminar insulator solidifying and annealing on amorphous alloy material. The iron losses of motors made of amorphous alloy and baseline silicon steel sheets are compared and discussed.

This paper opted for an exploratory study using the experimental analysis and loss separation methods. Two amorphous alloy cores are produced and tested. The iron losses of motors made of amorphous alloy and silicon steel sheets are calculated and compared based on the measured specific iron losses. Three wound amorphous alloy core samples are made and measured. The iron losses are separated and compared by considering the manufacturing influences.

This paper provides empirical insights about what change is brought in amorphous alloy material after manufacturing. The results have shown that, for amorphous alloy cores without the annealing process, the loss increase caused by solidifying is mainly the eddy current loss, while it is mainly the hysteresis loss component for annealed amorphous alloy cores.

This paper presents for the first time the measured results of manufactured amorphous alloy cores. This paper fulfils the need to manufacture amorphous alloy motors properly for the producers.

The purpose of this paper is to present the distribution of the magnetic field and additional losses analysis of the induction motors (IM) with opened and closed rotor slots.

In the field-circuit approach the distribution and changes of magnetic flux density in the motor are computed using a time-stepping finite element method. The additional losses in each element are evaluated at different frequencies.

An approximate analytical formulation is derived for rapid losses computation confirmed by the results of field-circuit method. For high-voltage motors due to the size ratios of the core and relatively deep stator and rotor slots major role in causing loss of higher harmonics play a fundamental slot harmonics. Higher harmonics order bigger than 100 cause only small part of total higher harmonics core losses. Closed rotor slots construction influenced significantly on no-load losses mainly due to reduction of losses at slot upper part. For nominal load condition that influence is not so strong according to the saturation of slot tips by rotor leakage flux. Nevertheless, core losses at load are several times higher as at no-load.

In future research authors will take into account motors feed from PWM inverter, working in the frequency range up to 400 Hz.

The results of investigation will be used in more detailed design of IMs especially for motors with closed rotor slots.

The methods presented in the paper was not used before. Also results of additional losses in the motor core calculation, especially according motors with closed slots at no load and load conditions are new.

The purpose of this study is to find out the influence degree of harmonic current on the generator operating parameters. In practical operation of the salient-pole synchronous generator, the heat generated by eddy current loss may lead to the breaking of damper winding, and the damper winding is a key component for ensuring the reliable operation of generators. Therefore, it is important to study the distribution characteristics and the influence factors of eddy current loss. Taking a 24-MW bulb tubular turbine generator as a reference, the influence factors that affect the eddy current loss of damper winding are analyzed.

A two-dimensional (2-D) electromagnetic field model of the generator is established, and the correctness of the model is verified by comparing simulation results and experiment data. The eddy current losses of damper winding in various conditions are calculated by using the finite element method.

It is identified that the cogging effect, pole shoe magnetic saturation degree, pole arc coefficient and armature reaction are the main factors that affect the eddy current loss of the generator rotor. When the generator is installed with magnetic slot wedges, the distribution characteristic of eddy current loss is obtained through the study of the eddy current density distributions in the damper bars. The variations of eddy current losses with time are gained when the generator has different permeability slot wedges, pole arc coefficients and pole shoe magnetic saturation degrees.

The study of this paper provides a theoretical reference for the design and optimization of bulb tubular turbine generator structure.

The research can help enhance the understanding of eddy current distribution characteristics and influence factors of eddy current loss in bulb tubular turbine generator.

The aim of this paper is to estimate the iron losses for an induction machine in the healthy case taking the slotting effect into account and to study the effect of an inter‐turn short‐circuit on these losses. Theoretical results are then compared with experimental ones.

A simple analytical model of iron losses allows one to calculate and to appreciate the contribution of the slotting effect on induction machine iron losses without and with an inter‐turn stator short‐circuit. This semi‐analytical approach is based on the iron stator and rotor flux density repartition which is deduced from the air‐gap flux density.

The iron losses are not only due to the fundamental air‐gap flux density, but also to the slotting harmonics. In fact, the slotting effect generates harmonic flux density waves with very low magnitudes but with high‐angular velocities, leading to non‐negligible harmonic iron dynamic losses which have similar values on both the stator and the rotor. The inter‐turn short‐circuit generates an iron losses and a slotting harmonic contribution increase.

Experimental measurements give the total iron losses. They do not allow separating the fundamental and the slotting harmonics contribution.

The knowledge of the iron losses behaviour in the healthy machine taking into account the slotting effect is important to optimize the design. The fault contribution on these losses allows one to estimate the damage which can be engendered by the fault.

Generally, iron losses studies and calculations are performed numerically using finite element software. The analytical approach can be interesting because it allows one to make faster calculations and to analyze the influence of the machine geometric parameters.

Besides other approaches, fuel savings in automotive applications and energy savings, in general, also require high‐efficiency gearboxes. Different approaches are shown regarding how to further improve gearbox efficiency. This paper aims to address these issues.

The paper takes the following approach: theoretical and experimental investigations of bearing arrangements and gear design as well as lubricant type and lubricant supply to the components lead to efficiency optimisation.

No‐load losses can be reduced, especially at low temperatures and part‐load conditions when using low‐viscosity oils with a high viscosity index and low oil immersion depth or low spray oil supply of the components. Bearing systems can be optimised when using more efficient systems than cross‐loading arrangements with high preload. Low‐loss gears can contribute substantially to load‐dependent power loss reduction in the gear mesh. Low‐friction oils are available for further reduction of gear and bearing mesh losses. All in all, a reduction of the gearbox losses in an average of 50 per cent is technically feasible.

Results from different projects of the authors and from the literature are combined to quantitatively evaluate the potential of power loss reduction in gearboxes.

Fabric loss is a major contribution to material utilization. Minimizing fabric loss during spreading can reduce the total production costs for garment manufacturing. A traditional method of predicting the fabric loss during spreading is mainly based on the experience of domain experts or the historical data of production orders. Such method is subjective, not systematic and non‐repeatable. In this paper, assuming the spreading process is handled in a controlled manner and there are no flaws on the fabrics being spread, a mathematical model is constructed for predicting the total fabric loss in the spreading process. The total fabric loss includes the internal wastage (i.e. marker fallout), and the external wastage (including end loss, width loss, and splice loss). Other parameters such as marker length, number of splice lines, remnant, and roll length of fabric are also included in the model.

Aims to discuss iron loss analysis and experimenting with linear oscillating actuator for linear compressor.

The iron loss analysis of the linear oscillating actuator is performed by using ANSYS and iron loss curves, which is obtained by an Epstein test apparatus.

The way to calculate the iron loss of the linear oscillating actuator for the linear compressor and the method to experiment the iron loss of that can be studied.

Iron loss analysis of the linear compressor considering the motor part and the structure part is needed.

Each iron loss analysis method examined here can be used to analyze the iron loss of the linear motor.

This paper deals with the numerical modelling of electromagnetic losses in electrical machines, using electromagnetic field computations, combined with advanced material characterisations. The paper gradually proceeds to the actual reasons why the building factor, defined as the ratio of the measured iron losses in the machine and the losses obtained under standard conditions, exceeds the value of 1.