Engineering Associates (United States)

Pacific sardine is a dynamic population that undergoes natural boom-and-bust cycles. Despite sardines’ ecological and economic importance, the variability that governs population changes remains poorly understood. Understanding the influence of oceanography on the life history, migration, and population dynamics of sardines is important for fishery management. Over the history of the California Current sardine fishery, numerous studies have attempted to explain why the US and Mexican portions of the sardine biomass off the West Coast should be divided into Northern (Cold - NSP) and Southern (Temperate - SSP) subpopulations. Since 2015, a habitat model including a Sea Surface Temperature (SST) threshold has been used to delineate subpopulations. The assessment and management of the NSP is conducted by the US (using an SST threshold of 16.7° C), while that of the SSP has been conducted by Mexico (using a threshold of 17 °C). Meantime, new population genetics and stock structure studies have found that the reproductive ecology of Pacific sardine reflects a single, panmictic population spread over a wide geographic range and influenced by environmental forcing, suggesting that assumptions regarding the two-subpopulation hypothesis be reconsidered, along with the influence of oceanography on sardine population dynamics. The implications of a single sardine population are significant, as this could result in a review of current US fishery management policies and reference points used to set the annual fishing quotas. In this paper we discuss the importance of the California Current’s influence on the population dynamics of sardine, current fishery management, and management implications. • Pacific sardine is an iconic species with natural cycles driven by the environment. • Present science/management ignore dynamic recruitment patterns seen in sardines. • Recent studies question the hypothesis of Pacific sardine subpopulations. • Pacific sardines’ population dynamics should be included in science/management. • Conflicting science is reviewed and management alternatives are proposed.

This study presents a database of over 900 large-scale triaxial tests that were used to calibrate and refine the Leps strength envelopes for rockfill materials. A novel nonlinear shear strength criterion for rockfill is introduced that can replicate the Leps strength envelopes, is derived in terms of both shear/normal and principal stresses, employs a single fitting parameter with direct physical significance, and allows for smooth transitions between rockfill strength categories. An accompanying empirical model is presented to estimate rockfill strength based on void ratio and rock type, offering a practical tool for rapid application. The model simplifies to five strength envelopes and demonstrates strong predictive performance, while maintaining simplicity. The evaluation of prediction accuracy indicates that the strength model is applicable for soils with a median particle size greater than 2 mm and a fines content of less than 25%. Analysis by stress range reveals a limitation of power-law strength criteria: when calibrated using tests at very low confining stresses, power-law models can significantly over- or underestimate strength for normal stresses above 100 kPa. To address this, a 60-600 Guideline is proposed, recommending the exclusion of triaxial confining stresses below 60 kPa and inclusion of at least one test with a confining stress above 600 kPa to obtain reliable calibration of power-law strength criteria for rockfill from laboratory testing data. An improved methodology to convert triaxial test results into shear and normal stresses is also introduced, accounting for the nonlinearity of the failure envelope.

The public consumption of alcohol in Malaysia presents multifaceted legal, social, and health challenges, particularly in light of the country’s diverse cultural and religious composition. While alcohol is legally permitted for non-Muslims, Malaysia lacks a comprehensive federal law that specifically prohibits or regulates drinking in public spaces. Existing laws, including the Penal Code, Road Transport Act 1987, Excise Act 1976, and various local government bylaws, address alcohol-related concerns in a fragmented manner, leading to inconsistent enforcement and public confusion. Furthermore, Syariah enactments applicable only to Muslims further complicate the legal landscape, creating disparities in regulation and enforcement based on religious affiliation. This article critically examines the current statutory and regulatory framework governing public alcohol consumption in Malaysia, highlighting significant legislative gaps and enforcement challenges. By adopting a qualitative methodology, it draws on comparative legal models from jurisdictions such as Singapore, India, and the United Kingdom to demonstrate how coherent and targeted legal interventions can promote public order while respecting individual freedoms. Based on this analysis, the article proposes a structured, federal-level legal framework that incorporates uniform definitions, designated alcohol-free zones, time-based restrictions, and standardised local enforcement mechanisms. In advocating for reform, the article underscores the need for legal clarity, institutional coordination, and public education. A well-designed legal infrastructure would enhance regulatory coherence, promote responsible alcohol use, and reinforce public confidence in the rule of law. By balancing legal pluralism with universal principles of public safety and health, Malaysia can address the current legal ambiguities and build a more effective and inclusive regulatory system for managing alcohol consumption in public spaces.

We have analyzed several options for thermal dissipation and power delivery of wafer-scale systems. A twophase cooling unit was vertically integrated onto a silicon dielet. With a power density of <tex>$1 \mathrm{W} / \text{mm}^{2}$</tex> to mimic the high-power compute dielets on wafer-scale systems, we demonstrate a vertical heat extraction system scalable up to 300-mm wafer diameters with the potential to go to higher power densities.

This qualitative study explored the lived experiences of 10 retired female senior enlisted leaders assigned as first sergeant (1SG) and command sergeant major (CSM) in initial entry training (IET) to ascertain if their experiences shed light on the underrepresentation of female leaders in the basic combat training (BCT) environment. Data collection emphasized factors that led to success in the IET environment, as well as challenges and barriers they faced. The theoretical framework underpinning this study included the social role theory, which holds that the expectations for men and women are based on sex differences that regulate behaviour in an adult’s work and family life, and the role congruity theory of prejudice toward female leaders, which suggests women do not reach top-level positions because they are less capable than men and because women are judged more harshly when they are in leadership roles. Having to prove oneself, reaction to female leadership, family obligations, and fighting stereotypes emerged as barriers and challenges. Attributes needed for success in the IET BCT environment included Army values and toughness and tenacity. Coding of positions and male perception of female leaders emerged as barriers that preventfemales from attaining 1SG and CSM in the BCT environment. The findings support the social role theory and role congruity theory of prejudice toward female leaders. The results extend research on the representation of women in senior leadership positions because they illuminate female leaders in a nontraditional educational environment in the largest branch of the U.S. military. Keywords: women, leaders, U.S. Army, basic combat training, glass ceiling, women in leadership; leadership theories

High concentrations of ice crystals in convective storms have caused anomalous air temperature and airspeed readings during commercial and research flight operations. These anomalies occur when ice crystals are ingested in the heated probe inlet, melt or partially melt to liquid water, and then refreeze or remain in a liquid state depending on the probe heat and cloud conditions. In pitot probes, the refreezing may cause complete blockage of the total pressure, which causes airspeed anomalies. In total air temperature probes, the melted ice water may flow near the temperature sensing element and cause the total air temperature reading to approach 0 degree Celsius. During the High Ice Water Content (HIWC) RADAR and HIWC-2022 flight campaigns and the Convective Process Experiment (CPEX-CV) flight campaign, a total of 71 anomalies were recorded on the NASA DC-8 pitot probes when subjected to specific flight and cloud conditions. Similarly, a research total air temperature (TAT) probe mounted near the pitot probes had 19 anomalies. This paper presents analyses of the measured natural conditions that led to these TAT and pitot anomalies, identifies two types of pitot probe anomalies, applies a concentration factor to estimate local TWC conditions near the TAT and pitot probes, and identifies the static air temperature and pressure altitude where the anomalies occurred on the Part 33 Appendix D envelope.

Condensation heat transfer is involved in many industrial applications. Therefore, it is important to know the relative accuracy of the available methods for predicting heat transfer. Condensation can occur with saturated as well as superheated vapors. Predictive methods for both conditions were evaluated using a wide range of data. Twelve well-known correlations for the condensation of saturated vapor, including the most recent ones, were compared with data for 51 pure fluids and mixtures from 132 sources in horizontal and vertical channels of many shapes. Channel hydraulic diameters were 0.08–49 mm, the mass flux was 1.1–1400 kg/m2s, and the reduced pressure range was 0.0006–0.949. The fluids included water, CO2, ammonia, hydrocarbons, halocarbon refrigerants, various chemicals, and heat transfer fluids. The best predictive technique was identified. The three most commonly used models for heat transfer during the condensation of superheated vapors were studied. They were first compared with test data using measured saturated condensation and forced convection heat transfer coefficients to select the best model. The selected model was then compared with test data using various correlations for heat transfer coefficients needed in the model. The best correlations to use in the model were identified. The results of this research are presented, as are recommendations for use in design.

RationaleBronchiectasis is a chronic, progressive disease of bronchial dilation, inflammation, and scarring leading to impaired mucociliary clearance and increased susceptibility to infection. Identified causes include previous severe respiratory infections. A small, single-center UK study demonstrated a reduction in bronchiectasis exacerbations during the first year of the coronavirus disease (COVID-19) pandemic. No studies have been conducted in a U.S. (commercially insured) cohort to date.ObjectivesTo explore the impact of the COVID-19 pandemic on the frequency of exacerbations in a large cohort of commercially insured U.S. patients with bronchiectasis by testing the hypothesis that U.S. patients with bronchiectasis had fewer exacerbations during the pandemic.MethodsThis retrospective observational cohort study used health insurance claims data from Optum’s deidentified Clinformatics Data Mart database, which included U.S. patients and their covered dependents. Eligible patients were ⩾18 years of age with bronchiectasis; patients with other respiratory conditions were excluded. The main study cohort excluded patients with frequent asthma and/or chronic obstructive pulmonary disease diagnoses. The primary objective was to compare the bronchiectasis exacerbation rates before and during the COVID-19 pandemic.ResultsThe median number of exacerbations per patient per year decreased significantly from the year before the COVID-19 pandemic to the first year of the pandemic (1 vs. 0; P < 0.01). More patients had zero exacerbations during the first year of the pandemic than the year prior (57% vs. 24%; McNemar’s chi-square = 122.56; P < 0.01).ConclusionsIn a U.S. population-based study of patients with International Classification of Diseases codes for bronchiectasis, the rate of exacerbations during Year 1 of the COVID-19 pandemic was reduced compared with the 2-year time period preceding the pandemic.