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971.
Product bundling has become increasingly prevalent not only in consumer goods but also in the industrial sector. We study a purchasing problem in which a buyer must obtain necessary numbers of various stock items from a variety of vendors who charge different prices, have limited capacities and different levels of quality, and offer bundled products at discounted prices. We examine relationships among different bundling scenarios and show that the most general scenario is one in which free items are given to the buyer when sufficient quantities are purchased. We develop a mixed integer linear program that finds the purchasing strategy for the buyer that minimizes the total purchase cost. We present computational results which indicate that the problem is very tractable to solve optimally on a personal computer with standard optimization software. Finally, three extensions of the model are discussed.  相似文献   
972.
Total quality management (TQM) is a revolutionary approach to effective management. The research in TQM has emerged from practical needs of organizations embracing this philosophy, and the literature is mostly conceptual and practitioner-oriented. There is a lack of sound theoretical framework classifying past efforts and guiding future research. To fill the void, a study of the published TQM literature is undertaken. A review, classification, and analysis of the research in TQM spanning the last two decades is presented. A total of 226 TQM-related articles are identified from 44 refereed management journals published from 1970 to 1993. These articles are then classified and analyzed using the following two-dimensional scheme: (1) article orientation (conceptual, case study, empirical, analytical, simulation, and overview) and (2) article focus using the Malcolm Baldrige National Quality Award criteria. The analysis of the literature presents pertinent developments in each of the seven criteria. In addition, it provides future research directions as well as a ready reference of the TQM literature. The suggestions for research should guide future developments in the TQM field and help transform it into a formal discipline.  相似文献   
973.
This paper investigates long-term earnings differentials between African American and white men using data that match respondents in the Survey of Income and Program Participation to 30 years of their longitudinal earnings as recorded by the Social Security Administration. Given changing labor market conditions over three decades, we focus on how racial differentials vary by educational level because the latter has important and persistent effects on labor market outcomes over the course of an entire work career. The results show that the long-term earnings of African American men are more disadvantaged at lower levels of educational attainment. Controlling for demographic characteristics, work disability, and various indicators of educational achievement does not explain the lower long-term earnings of less-educated black men in comparison to less-educated white men. The interaction arises because black men without a high school degree have a larger number of years of zero earnings during their work careers. Other results show that this racial interaction by educational level is not apparent in cross-sectional data which do not provide information on the accumulation of zero earnings over the course of 30 years. We interpret these findings as indicating that compared to either less-educated white men or highly educated black men, the long-term earnings of less-educated African American men are likely to be more negatively affected by the consequences of residential and economic segregation, unemployment, being out of the labor force, activities in the informal economy, incarceration, and poorer health.  相似文献   
974.
Sea-Level Rise (SLR) Projections from the National Oceanic and Atmospheric Administration (NOAA) and the U.S. Army Corp of Engineers (USACE) indicate increasing, and imminent, risk to coastal communities from tidal flooding and hurricane storm surge. Building on recent research related to the potential demographic impacts of such changes (Hauer et al. 2016, in Nat Clim Chang 3:802–806, 2017; Neumann et al. 2015; Curtis and Schneider in Popul Environ 33:28–54, 2011), localized flooding projections in the Miami Beach area (Wdowinski et al. in Ocean Coast Manag 126:1–8, 2016) and projected economic losses associated with this rise in projected SLR (Fu et al. Ocean Coast Manag 133:11–17, 2016); this research investigates the accrued current cost, in terms of real-estate dollars lost, due to recurrent tidal flooding and projected increases of flooding in Miami-Dade County. Most directly related to this line of research, Keenan et al. (2018) have recently produced results indicating that Climate Gentrification is taking place in Miami, FL with higher elevations in flood prone areas appreciating at a higher rate. In that vein of thinking, we seek to answer a question posed by such research: What is the actual accrued loss to sea-level rise over the recent past? To answer this question, we replicate well-documented estimation methods by combining publicly available sea-level rise projections, tide gauge trends, and property lot elevation data to identify areas regularly at risk of flooding. Combining recent patterns of flooding inundation with future forecasts, we find that properties projected to be inundated with tidal flooding in 2032 have lost $3.08 each year on each square foot of living area, and properties near roads that will be inundated with tidal flooding in 2032 have lost $3.71 each year on each square foot of living area. These effects total over $465 million in lost real-estate market value between 2005 and 2016 in the Miami-Dade area.  相似文献   
975.
Disaster research has drawn attention to how natural hazards transform local organizational dynamics and social inequalities. It has yet to examine how these processes unfold together over time. We begin to fill this gap with a county-level, longitudinal analysis that examines how property damages from natural hazards correlate not only with local shifts in poverty a year later but also counts of for-profit as well as bonding and bridging social capital organizations. Results show that poverty and all organizational types tend to increase with local hazard damages. They also show that poverty tends to increase most where the number of bonding social capital organizations is also increasing. This pattern suggests a Janus-faced dynamic in which bonding, or more inwardly focused, organizations that arise after disaster may end up inadvertently marginalizing those in more dire need.  相似文献   
976.
Food and nutrition insecurity remains a challenge in sub-Saharan Africa. Several studies have examined food and nutrition insecurity in urban or rural areas but have not captured the whole continuum. Between November and December 2013, 240 households were surveyed along the urban–rural continuum in Northern Ghana. The study objective was to understand the socio-spatial dynamics of household food and nutrition insecurity and to investigate the role played by urban, peri-urban and rural agriculture. The study found that there was more involvement in agriculture in rural areas compared to peri-urban areas and urban areas. Households from urban areas were more food insecure (HFIAS >?11) compared to their counterparts in peri-urban and the rural areas. Stunting increased by 3.4 times (p?=?0.048) among households located in the peri-urban area. Wasting was reduced by 0.16 times among household that produced staple food or vegetables (p?=?0.011). Overweight was reduced by 0.04 times among households that produced livestock (p?=?0.031). The results reveal a socio-spatial dimension of food and nutrition insecurity that is related to agricultural activities.  相似文献   
977.

Problem

Pacific Islanders are disproportionately burdened by poorer maternal health outcomes with higher rates of pre-term births, low birth weight babies, infant mortality, and inadequate or no prenatal care.

Purpose

The purpose of this study was twofold: (1) to explore maternal health care providers’ perceptions and experiences of barriers in providing care to Marshallese women, and (2) providers perceived barriers of access to care among Marshallese women. This is the first paper to explore perceived barriers to maternal health care among a Marshallese community from maternal health care providers’ perspectives in the United States.

Methods

A phenomenological, qualitative design, using a focus group and in-depth interviews with 20 maternal health care providers residing in northwest Arkansas was chosen.

Findings

Several perceived barriers were noted, including transportation, lack of health insurance, communication and language, and socio-cultural barriers that described an incongruence between traditional and Western medical models of care. There was an overall discord between the collectivist cultural identity of Marshallese families and the individualistic maternal health care system that merits further research.

Discussion

Solutions to these barriers, such as increased cultural competency training for maternal health care providers and the incorporation of community health workers are discussed.  相似文献   
978.
The purpose of this study was to explore LGBTQ women’s experiences with unwritten or formal dress codes at work. I asked: What are LGBTQ women’s experiences in the workplace with appearance management, and what are LGBTQ women’s experiences navigating the written and unwritten dress codes in the workplace? To answer the research question, interviews were conducted with 24 self-identifying LGBTQ women. Six key themes emerged from the data. Themes included (1) expressed sexual identity in appearance, (2) unwritten dress codes in work environments did not always allow for expression of sexual identity in appearance, (3) motivations for pressure or desire to conceal expression of sexual identity in appearance at work, (4) negotiations of revealing or concealing sexual identity in appearance in the workplace impacted levels of comfort and confidence, (5) verbal and nonverbal negative experiences related to appearance at work, and (6) received compliments about appearance at work.  相似文献   
979.
Psychosocial benefits of activism include increased empowerment, social connectedness, and resilience. Yet sexual minority women (SMW) and transgender individuals with multiple oppressed statuses and identities are especially prone to oppression-based experiences, even within minority activist communities. This study sought to develop an empirical model to explain the diverse meanings of social justice activism situated in SMW and transgender individuals’ social identities, values, and experiences of oppression and privilege. Using a grounded theory design, 20 SMW and transgender individuals participated in initial, follow-up, and feedback interviews. The most frequent demographic identities were queer or bisexual, White, middle-class women with advanced degrees. The results indicated that social justice activism was intensely relational, replete with multiple benefits, yet rife with experiences of oppression from within and outside of activist communities. The empirically derived model shows the complexity of SMW and transgender individuals’ experiences, meanings, and benefits of social justice activism.  相似文献   
980.
Although a growing body of research focuses on Americans’ attitudes toward same-sex couples as parents, very few include measures of religion, and those that do fail to capture its multidimensional nature. Furthermore, many past studies relied on convenience samples of college students, or samples gathered outside the United States. Multivariate analyses of the 2012 General Social Survey—a nationally representative sample of adults in the United States—reveal that a slim majority of Americans still do not believe same-sex couples can parent as well as male-female couples, and the religious beliefs, behaviors, and affiliations of Americans are significantly and at times differentially associated with appraisals of same-sex couples’ parenting abilities. It appears that although religion is generally associated with more negative appraisals of the parenting abilities of same-sex couples, it is not uniformly so. Americans’ immediate religious and cultural context can shape their appraisals of homosexuality in diverse ways.  相似文献   
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