A cost-effective approach for optimal energy management of a hybrid CCHP microgrid with different hydrogen production considering load growth analysis

An optimum design and energy management of various distributed energy resources is investigated in a hybrid microgrid system with the examination of electrical, heating, and cooling demand. This paper suggested an optimal approach to design and operate a microgrid incorporating with battery energy storage, thermal energy storage, photovoltaic arrays, fuel cell, and boiler with minimization of the total operational cost of the hybrid microgrid. Two different hydrogen production methods are considered to assure the advantage of the developed proposed methodology. Furthermore, besides natural gas, residential and municipal wastes are collected and are utilized to produce electricity in fuel cell units. Load growth for different type of loads is also considered. The new number of households are added to the proposed system in different years and the proposed program is determined the optimum size of each employed resources to add each year for satisfying the total demand. To find out the optimum energy management and the optimum capacity of each employed distributed energy resources, a meta-heuristic Particle Swarm Optimization Algorithm is utilized. It is concluded from the results that by utilizing residential waste, the amount of natural gas consumption by fuel cells is reduced about 6.2%, and by utilizing residential plus municipal waste, the reduction is about 26.7%. It is also observed that the amount of CO₂ emission is reduced significantly (46.8%) in the case of utilization of produced heat by fuel cells. Finally, the results confirmed the efficacy of the suggested optimal energy management of the hybrid microgrid.     

Numerical simulation of strain-rate dependent transition of transverse tensile failure mode in fiber-reinforced composites

This study numerically simulates strain-rate dependent transverse tensile failure of unidirectional composites. The authors’ previous study reported that the failure mode depends on the strain rate, with an interface-failure-dominant mode at a relatively high strain rate and a matrix-failure-dominant mode at relatively low strain rate. The present study aims to demonstrate this failure-mode transition by a periodic unit-cell simulation containing 20 fibers located randomly in the matrix. An elasto-viscoplastic constitutive equation that involves continuum damage mechanics regarding yielding and cavitation-induced brittle failure is used for the matrix. A cohesive zone model is employed for the fiber–matrix interface, considering mixed-mode interfacial failure. For the results, the relationship between failure modes and the strain rate is consistent with the authors’ previous studies.     

Morphogenesis, morphology and men: pattern formation from embryo to mind

In 1952, Alan Turing published his last work on the concept of embryonic morphogenesis, propounding a computational framework for pattern formation within the developing embryo. This concept of morphogenesis and the concept of embryo pattern formation based on chemical diffusion patterns were corroborated with the discovery of the Homeobox or Hox genes. In the following decades, Hox gene research has expanded and is now shown to underlie the variety of morphological novelties that we experience in nature, the patterning of structural aspects of different organs including the brain and also mutant animals that may in the future give rise to novel speciation. Turing had the foresight and vision and with his work created the field of computational biology and mathematical modeling in biological systems. In this paper, we will discuss the concept of Hox genes, their role in patterning the embryo, how it relates to Turing’s concept of morphogenesis and what further insights they may provide.     

Biochemistry and biomechanics of healing tendon: Part I. Effects of rigid plaster casts and functional casts

OBJECTIVE: The state psychiatric hospital is experiencing an increase in medically sick and aging patients who die of natural causes while hospitalized. This study explored the "medicalization" of the state hospital by examining the prevalence of medical illness and its relationship with psychiatric illness and age among state hospital psychiatric inpatients who died of natural causes--deaths that were not accidents, homicides, or suicides. METHODS: A total of 179 inpatients who died of natural causes at Western State Hospital in Washington State between 1989 and 1994 were studied retrospectively through case file review. Their demographic and institutional characteristics and psychiatric diagnoses were compared with those of others treated at the hospital (N=9,258). The medical diagnoses of patients who died were analyzed by age and psychiatric condition. RESULTS: The patients who died were much older than the other patients treated during the study period. Two-thirds of those who died had organic mental disorders, mostly dementia, whereas only a fifth of the other patients had these disorders. The patients who died had a mean of eight physical illnesses, with a range from none to 21. Circulatory and respiratory conditions were most prevalent, affecting half to two-thirds of patients; these conditions had high rates of comorbidity with organic mental disorders. CONCLUSIONS: The characteristics of the state hospital population and the services provided are shifting in response to mental health reform and new policies on patient self-determination. Increased emphasis on medical care added to traditional psychiatric services will require increased financial and personnel resources.     

A satellite snow depth multi-year average derived from SSM/I for the high latitude regions

The hydrological cycle for high latitude regions is inherently linked with the seasonal snowpack. Thus, accurately monitoring the snow depth and the associated aerial coverage are critical issues for monitoring the global climate system. Passive microwave satellite measurements provide an optimal means to monitor the snowpack over the arctic region. While the temporal evolution of snow extent can be observed globally from microwave radiometers, the determination of the corresponding snow depth is more difficult. A dynamic algorithm that accounts for the dependence of the microwave scattering on the snow grain size has been developed to estimate snow depth from Special Sensor Microwave/Imager (SSM/I) brightness temperatures and was validated over the U.S. Great Plains and Western Siberia.

The purpose of this study is to assess the dynamic algorithm performance over the entire high latitude (land) region by computing a snow depth multi-year field for the time period 1987–1995. This multi-year average is compared to the Global Soil Wetness Project-Phase2 (GSWP2) snow depth computed from several state-of-the-art land surface schemes and averaged over the same time period. The multi-year average obtained by the dynamic algorithm is in good agreement with the GSWP2 snow depth field (the correlation coefficient for January is 0.55). The static algorithm, which assumes a constant snow grain size in space and time does not correlate with the GSWP2 snow depth field (the correlation coefficient with GSWP2 data for January is − 0.03), but exhibits a very high anti-correlation with the NCEP average January air temperature field (correlation coefficient − 0.77), the deepest satellite snow pack being located in the coldest regions, where the snow grain size may be significantly larger than the average value used in the static algorithm. The dynamic algorithm performs better over Eurasia (with a correlation coefficient with GSWP2 snow depth equal to 0.65) than over North America (where the correlation coefficient decreases to 0.29).     

Medicare coverage of outpatient ambulatory intravenous antibiotic therapy: a program that pays for itself

A number of studies have documented the safety, efficacy, and cost-effectiveness of outpatient intravenous (i.v.) antibiotic therapy for patients with infectious diseases. Nevertheless, Medicare policy prohibiting coverage of outpatient, self-administered drugs has severely limited access of Medicare patients to ambulatory i.v. therapy, thus forcing them to rely on more costly, impatient hospital care. To test the hypothesis that a new Medicare benefit providing coverage for ambulatory i.v. antibiotic therapy could significantly reduce the program's expenditures for the treatment of infectious diseases (including pneumonia, osteomyelitis, cellulitis, and endocarditis), a cost model was constructed with use of patient care information from the clinical literature as well as clinical experts, Medicare data, and other medical claims databases. The model shows cumulative 5-year savings of nearly $1.5 billion associated with the new Medicare benefit. Policy makers should consider implementing such a benefit.     

Development of a multiple intermittent fault testing strategy

This paper examines the effects of multiple intermittent faults on an overall circuit testing procedure. Different testing strategies are developed which depend on λ, the rate of intermittent fault activity. In addition, the effects of masking intermittent faults in redundant circuits are explored.     

Flexible practices for mass production goals: economic governance in the Indian automobile industry

This paper explains the remarkable restructuring of the Indianautomobile industry. It argues that firms have had to deploynew governance modes (flexible industrial practices) for economiccoordination to overcome supply bottlenecks and meet expandingdemand. Firms that failed to adopt these practices performedpoorly, while firms that attained economies of scale were ableto graduate to exploiting economies of scope. The industry experiencesuggests that new governance modes can serve mass productiongoals in developing economies and not just cushion market volatility,for which they were designed.     

The effect of fiber volume fraction on filament wound composite pressure vessel strength

This paper is a continuation of previous research reported in Ref. [1]. The previous paper discussed the relationship between fiber volume fraction in filament wound composite vessels and failure pressure. This research included a design of experiment investigation of manufacturing and design variables that affect composite vessel quality and strength. Statistical analysis of the data shows that composite vessel strength was affected by the manufacturing and design variables. In general, it was found that the laminate stacking sequence, winding tension, winding-tension gradient, winding time, and the interaction between winding-tension gradient and winding time significantly affected composite strength. The mechanism responsible for increases in composite strength was related to the strong correlation between fiber volume fraction in the composite and vessel strength. Cylinders with high-fiber volume in the hoop layers tended to deliver high-fiber strength. This paper further examines the relationship between fiber volume fraction and fiber strain to failure. Data from unidirectional strand tests and additional vessel tests are presented. A computer program that is based on the thermokinetics of the resin and processing conditions is used to calculate the fiber volume fraction distribution in the filament wound vessel. The strand's strength-versus-fiber volume data together with the computer program are used to predict composite vessel burst pressure. In general, good agreement with experimental data is observed.