Multi-site production planning in hybrid make-to-stock/make-toorder production environment

Today competitive environment has enforced practitioners and researchers to pay great attention to issues enhancing both production and marketing competitiveness. To do so, it has been obligatory for the firms to consider production side activities while customer requirements are on the other side of competition. In this regard, hybrid make-to-stock (MTS)/make-to-order (MTO) production systems have revealed outstanding results. This paper addresses multi-site production planning of a hybrid manufacturing firm for the first time in the hybrid systems' body of literature. In this regard, a network of suppliers, manufacturers and customers is considered for which a mixed-integer mathematical model is proposed. Objective function of the proposed mathematical model seeks to maximize profitability of the manufacturing firm. Because of computational complexity of the developed mathematical model, a genetic algorithm is developed upon which numerical experiments are reported in order to show validity and applicability of the proposed model

Optimal dynamic pricing and replenishment policies for deteriorating items

Marketing strategies and proper inventory replenishment policies are often incorporated by enterprises to stimulate demand and maximize profit. The aim of this paper is to represent an integrated model for dynamic pricing and inventory control of deteriorating items. To reflect the dynamic characteristic of the problem, the selling price is defined as a time-dependent function of the initial selling price and the discount rate. In this regard, the price is exponentially discounted to compensate negative impact of the deterioration. The planning horizon is assumed to be infinite and the deterioration rate is time-dependent. In addition to price, the demand rate is dependent on advertisement as a powerful marketing tool. Several theoretical results and an iterative solution algorithm are developed to provide the optimal solution. Finally, to show validity of the model and illustrate the solution procedure, numerical results are presented

Probing the large-scale clustering of fast radio bursts with CHIME/FRB

Explaining the nature of extragalactic fast radio bursts (FRBs) has puzzled astrophysicists since 2007. In this thesis, we introduce the CHIME/FRB instrument, an FRB search engine that could solve this puzzle through FRB population studies. We explore CHIME/FRB science results, with an emphasis on the FRB-galaxy correlation. First, we formulate a framework for characterizing FRBs (e.g. by constraining their redshift and host dispersion measure distributions) through angular cross-correlations with large-scale structure. Using this machinery we model, forecast and simulate the FRB-galaxy correlation for two distinct FRB models. Then, we apply this technique to real data, using the first CHIME/FRB catalog along with five photometric redshift catalogs of galaxies. Computing the FRB-galaxy cross power spectrum, we find a statistically significant (p-value ~ 10⁻⁴, accounting for look-elsewhere factors) cross-correlation between CHIME FRBs and galaxies in the redshift range 0.3 ≲ z ≲ 0.5. The strength and angular scale of the cross-correlation are consistent with an order-one fraction of CHIME FRBs being in this redshift range, and in the same dark matter halos as the survey galaxies. Finally, we find statistical evidence for a subpopulation of FRBs with large host dispersion measure (host DM ~ 400 pc/cm³) at z ~ 0.4. We show that such large host DMs could be explained by a small population of FRBs near the centers (r ≲ 100 kpc) of large (M ~ 10¹⁴ M⊙) halos

A multi-objective genetic algorithm for a mixed-model assembly U-line balancing type-I problem considering human-related issues, training, and learning

Mixed-model assembly lines are increasingly accepted in many industrial environments to meet the growing trend of greater product variability, diversification of customer demands, and shorter life cycles. In this research, a new mathematical model is presented considering balancing a mixed-model U-line and human-related issues, simultaneously. The objective function consists of two separate components. The first part of the objective function is related to balance problem. In this part, objective functions are minimizing the cycle time, minimizing the number of workstations, and maximizing the line efficiencies. The second part is related to human issues and consists of hiring cost, firing cost, training cost, and salary. To solve the presented model, two well-known multi-objective evolutionary algorithms, namely non-dominated sorting genetic algorithm and multi-objective particle swarm optimization, have been used. A simple solution representation is provided in this paper to encode the solutions. Finally, the computational results are compared and analyzed

The comparison of the effects of chlorhexidine mouthwash alone and Chlorhexidine mouthwash followed by oral suctioning on oral hygiene of critically Ill patients Kritik hastalari{dotless}n aǧi{dotless}z hijyeninde tek başi{dotless}na Klorheksidin gargara ve Klorheksidin gargarayi{dotless} takiben aǧi{dotless}z sekresyonlari{dotless}ni{dotless}n vakumla çekilmesinin etkilerinin karşi{dotless}laşti{dotless}rmasi{dotless}

Aim: Oral hygiene is one of the main issues in nursing care, being especially important among patients admitted to intensive care units (ICU). The aim of the study was to assess the effect of Chlorhexidine mouthwash alone and 0.2 Chlorhexidine mouthwash followed by oral suctioning on oral hygiene in ICU patients. Material and Methods: In a semi-experimental research design, 90 patients who were admitted to the ICUs were selected. Patients were randomly divided into two groups. In group I, 0.2 chlorhexidine mouthwash alone was applied and in group 2, 0.2 chlorhexidine mouthwash was followed by oral suctioning. These procedures were repeated for 7 consecutive days. The oral hygiene status of patients was assessed by using a Beck checklist on the 1 st and 7 th days of ICU admission. Results: Oral hygiene scores of group I on the 1 st and 7 th days were 12.4 and 14.3 respectively. In group II, the scores of the 1 st and 7 th days were 11.8 and 10.5 respectively. Oral hygiene status of group I was poorer on the 7 th day, but in group II oral hygiene had improved on the 7 th day of application. Conclusion: We found that using a 0.2 chlorhexidine solution alone is not enough for oral care of patients in the ICU and suctioning of the oral secretions after 0.2 chlorhexidine mouthwash will improve oral hygiene in critically ill patients

The effect of eye mask on sleep quality in patients of coronary care unit O efeito da mascara de olhos na qualidade de sono em pacientes em uma unidade coronariana

Objectives: Patients in coronary care unit (CCU) are at risk of sleep deprivation. This study investigated effects of eye mask on sleep quality in patients of CCU in Southeast of Iran by a cross-over design. Methods: Using Verran and Snyder-Halpern Sleep Scale (VSH Sleep Scale), quality sleep of 60 patients with and without usage of eye mask were evaluated. This tool consists of 16 items that includes three main sleep sub scales: disturbance, effectiveness, and supplementation. Results: In total, 34, 22 and 4 out of 60 patients were admitted to CCU due to myocardial infarction (MI), chest pain and angina pectoris, respectively. Mean time of patients' nocturnal sleep was 6.6 ± 1.1 hours. Using eye mask have statistically significant increased the quality of sleep in subscales disturbance and effectiveness (p < 0.05). Conclusion: In general, the use of eye mask is an easy and cheap method to improve the quality of sleep in CCU patients

Kidney Stone Development among Older Adults in Iran

Aim: Incidence and prevalence of kidney stone development have been increased in the recent years. Present study aimed to determine prevalence and risk factors of kidney stone development among adults more than 65 years old. Methods: This cross-sectional study conducted in Kashani Hospital at Shahrekord, Iran. Data on all adults more than 65 years who were admitted to the lithotripsy unit of Kashani hospital in Shahrekord, were derived from medical records, in the period of January 2011 to December 2011. Results: Of 1170 admitted patients to the lithotripsy unit of the hospital, 181 (15.5%) patient were older than 65 years, with 95 female (52.5%) and 86 male (47.5%). Results of independent t test showed significant difference in stone development between male and female patients (p<0.05). The age of 73.5% (n=133) of patients were in between 65 to 74 years. Results of ANOVA showed significant difference in stone development between three age groups (p<0.05). Rate of patients admission in summer with 34.3% (n=62) was higher than other seasons. Results of ANOVA showed significant difference in stone development between four seasons of year (p<0.05). Conclusion: Results of present study showed that the risk of kidney stone development in older people (more than 65) is high. In addition, female sex, age group 65-74 years, region of residence and summer season might be considered as potential risk factors for increasing the risk of kidney stone development

The comparison of the effects of education provided by nurses on the quality of life in patients with congestive heart failure (CHF) in usual and home-visit cares in Iran.

Quality of life (QOL) can be considered as a quality indicator of health care systems and nurses can play an important role to improve QOL in patients with congestive heart failure (CHF). The aim of this study was to determine the effects of education provided by nurses on the QOL in patients with CHF in home-visit care compared to usual care. In a single-blind randomized controlled trial conducted from September 2011 to June 2012, 110 patients with CHF were randomly assigned into two groups. While patients in group I were received usual education at the time of hospital discharge, patients in Group II, in addition to usual education, were received special education regards to their illness by nurses who visited patients in their homes. The 36-item short-form (SF-36) questionnaire was used to evaluate the patient's QOL at the time of discharge and also six months after hospital discharge. At the time of hospital discharge, mean score of all 8 sub-score of SF-36 questionnaire was 63.4±7.8 in patients of group II and 61.1±6.4 in patients of group I, respectively (P> 0.05). QOL was decreased in group I and increased in group II compared to the time of hospital discharge. After six months, mean score of QOL was higher in group II than in group I. QOL of patients with CHF were decreased after hospital discharge. Education provided by nurses in home-visit care could improve the QOL in patients with CHF, based on the findings of this study

Occupational Health Services Integrated in Primary Health Care in Iran

Introduction: A healthy workforce is vital for maintaining social and economic development on a global, national and local level. Around half of the world's people are economically active and spend at least one third of their time in their place of work while only 15% of workers have access to basic occupational health services. According to WHO report, since the early 1980s, health indicators in Iran have consistently improved, to the extent that it is comparable with those in developed countries. In this paper it was tried to briefly describe about Health care system and occupational Health Services as part of Primary Health care in Iran. Methods: To describe the health care system in the country and the status of occupational health services to the workers and employers, its integration into Primary Health Care (PHC) and outlining the challenges in provision of occupational health services to the all working population. Findings: Iran has fairly good health indicators. More than 85 percent of the population in rural and deprived regions, for instance, have access to primary healthcare services. The PHC centers provide essential healthcare and public-health services for the community. Providing, maintaining and improving of the workers' health are the main goals of occupational health services in Iran that are presented by different approaches and mostly through Workers' Houses in the PHC system. Conclusions: Iran has developed an extensive network of PHC facilities with good coverage in most rural areas, but there are still few remote areas that might suffer from inadequate services. It seems that there is still no transparent policy to collaborate with the private sector, train managers or provide a sustainable mechanism for improving the quality of services. Finally, strengthening national policies for health at work, promotion of healthy work and work environment, sharing healthy work practices, developing updated training curricula to improve human resource knowledge including occupational health professionals are recommended