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1.
Many hope that ocean waves will be a source for clean, safe, reliable and affordable energy, yet wave energy conversion facilities may affect marine ecosystems through a variety of mechanisms, including competition with other human uses. We developed a decision-support tool to assist siting wave energy facilities, which allows the user to balance the need for profitability of the facilities with the need to minimize conflicts with other ocean uses. Our wave energy model quantifies harvestable wave energy and evaluates the net present value (NPV) of a wave energy facility based on a capital investment analysis. The model has a flexible framework and can be easily applied to wave energy projects at local, regional, and global scales. We applied the model and compatibility analysis on the west coast of Vancouver Island, British Columbia, Canada to provide information for ongoing marine spatial planning, including potential wave energy projects. In particular, we conducted a spatial overlap analysis with a variety of existing uses and ecological characteristics, and a quantitative compatibility analysis with commercial fisheries data. We found that wave power and harvestable wave energy gradually increase offshore as wave conditions intensify. However, areas with high economic potential for wave energy facilities were closer to cable landing points because of the cost of bringing energy ashore and thus in nearshore areas that support a number of different human uses. We show that the maximum combined economic benefit from wave energy and other uses is likely to be realized if wave energy facilities are sited in areas that maximize wave energy NPV and minimize conflict with existing ocean uses. Our tools will help decision-makers explore alternative locations for wave energy facilities by mapping expected wave energy NPV and helping to identify sites that provide maximal returns yet avoid spatial competition with existing ocean uses.  相似文献   

2.
Transitioning from fossil fuels to renewable energy is fundamental for halting anthropogenic climate change. However, renewable energy facilities can be land‐use intensive and impact conservation areas, and little attention has been given to whether the aggregated effect of energy transitions poses a substantial threat to global biodiversity. Here, we assess the extent of current and likely future renewable energy infrastructure associated with onshore wind, hydropower and solar photovoltaic generation, within three important conservation areas: protected areas (PAs), Key Biodiversity Areas (KBAs) and Earth's remaining wilderness. We identified 2,206 fully operational renewable energy facilities within the boundaries of these conservation areas, with another 922 facilities under development. Combined, these facilities span and are degrading 886 PAs, 749 KBAs and 40 distinct wilderness areas. Two trends are particularly concerning. First, while the majority of historical overlap occurs in Western Europe, the renewable electricity facilities under development increasingly overlap with conservation areas in Southeast Asia, a globally important region for biodiversity. Second, this next wave of renewable energy infrastructure represents a ~30% increase in the number of PAs and KBAs impacted and could increase the number of compromised wilderness areas by ~60%. If the world continues to rapidly transition towards renewable energy these areas will face increasing pressure to allow infrastructure expansion. Coordinated planning of renewable energy expansion and biodiversity conservation is essential to avoid conflicts that compromise their respective objectives.  相似文献   

3.
The new economic challenges and recent trends in globalization have made it very difficult for Canadian forest product companies to improve their financial position without the coordinated involvement of the entire company, including their supply chains (distributed facilities, company offices, industrial customers, and distributors). Such a new level of efficiency involves their distributed facilities and offices spread around the world, and their customers. One consequence of this new reality is that forest products companies are now facing the need to re-engineer their organizational processes and business practices with their partners. To do this they must adopt new technologies to support the coordination of their planning and control efforts in a customer-centered environment. This paper first proposes a generic software architecture for development of an experimentation environment to design and test distributed advanced planning and scheduling systems. This architecture enables combination of agent-based technology and operations research-based tools in order to first take advantage of the ability of agent technology to integrate distributed decision problems, and, second, to take advantage of the ability of operations research to develop and exploit specific normative decision models. Next, this paper describes how this architecture has been configured into an advanced planning and scheduling tool for the lumber industry. Finally, we present how an application of this advanced planning tool is currently being validated and tested in a real manufacturing setting.  相似文献   

4.
Regulatory pressures and capacity constraints are forcing the biopharmaceutical industry to consider employing multiproduct manufacturing facilities running on a campaign basis. The need for such flexible and cost-effective manufacture poses a significant challenge for planning and scheduling. This paper reviews the problem of planning and scheduling of biopharmaceutical manufacture and presents a methodology for the planning of multiproduct biopharmaceutical manufacturing facilities. The problem is formulated as a mixed integer linear program (MILP) to represent the relevant decisions required within the planning process and is tested on two typical biopharmaceutical industry planning problems. The proposed formulation is compared with an industrial rule based approach, which it outperforms in terms of profitability. The results indicate that the developed formulation offers an effective representation of the planning problem and would be a useful decision tool for manufacturers in the biopharmaceutical industry particularly at times of limited manufacturing capacity.  相似文献   

5.
Manufactures of biotechnological/biological products (including vaccines) frequently make changes to manufacturing processes of products both during development and after approval. In our case, a non-inferiority bridging study was carried out to demonstrate that changes in the production plant facilities of Cuban recombinant hepatitis B vaccine, Heberbiovac HB, did not affect the safety and immunogenicity of the vaccine. This controlled, randomized, doubled-blinded trial included 501 volunteers, aged between 20 and 64, who were given three doses of vaccine (20 microg HBsAg/mL) at month 0, 1, and 2. Four lots were evaluated (three corresponding to the new production facilities and a control one produced in the older facilities). One month after the third dose, were observed protective levels of anti-HBsAg in 97% of the subjects that concluded the study with a geometric mean antibody titer (GMT) of 931.18 IU/L. Normal values of body mass index (BMI), the younger ages, and being a female, were significantly related to a good antibody response. The vaccine was well tolerated. Pain at the injection site was the most commonly reported symptom. We conclude that Heberbiovac HB vaccine maintains its characteristics after the modifications carried out in the production plant facilities and both, lot obtained in previous facilities and in the new ones, are comparable in terms of safety and immunogenicity.  相似文献   

6.
OBJECTIVE: Obesity is typically developed over long time and reflected in an energy imbalance, which is too small to be measured and controlled. Our objective is to formulate a mathematical model for the relation between the change in body mass and the values of the energy intake and the energy expenditure, controlled by the physical activity factor PAF. DATA AND THEORY: The uncontrolled components of energy expenditure increases as result of body mass increase: expenditure of a larger mass and expenditure to convert matter in intake into tissue. Both contributions depend on the fraction of fat in the added tissue. Based on data from the literature, the fraction of fat in added tissue and the energy required to convert energy into tissue are estimated and included in the model. RESULTS: Application of the theory shows that an increase in body mass of 1 kg/year corresponds to an energy imbalance of 71 kJ/d for men. Of this imbalance, 82% are stored as new tissue, while 18% are used for energy conversion. If a man in steady state changes energy intake by 0.1 MJ/d, keeping the physical activity factor constant, then the corresponding increase in steady-state body mass is 1.77 kg/PAF, and it will take 320/PAF days before half the change of body mass has taken place. A typical value for PAF is 1.8. CONCLUSION: Energy-based theoretical relations between the various factors involved in energy balance help identifying and quantifying the components of the energy balance and understanding their relations during development of obesity. The inclusion of increased energy expenditure to convert food energy to tissue changes previous estimates of the energy imbalance by about 20 percent.  相似文献   

7.
OBJECTIVE--To collate information on current activity and facilities in British hospitals to assist the planning of future cancer services. DESIGN--12 hospitals delivering specialist cancer services provided information on the size of population served, activity levels related to non-surgical oncology for 1994-5, and facilities available. Inconsistencies in the recording of data were resolved through meetings of all participants. SETTING--Five single specialty NHS trusts and seven specialist cancer facilities within multispecialty trusts, serving a combined population of 24.3 million. MAIN OUTCOME MEASURES--Activity levels and facilities per million population served. RESULTS--The facilities available per million population served varied widely between centres. In contrast, the range in the number of new referrals per million population (seen either at the centre or in peripheral clinics) was relatively small. Considerable variations were observed in the number of attendances per patient and amount of radiotherapy and chemotherapy delivered. Overall it was estimated that 40-45% of all new cases of cancer are currently being referred to non-surgical oncologists. For the seven hospitals which could provide data on trends in activity, the average increase in chemotherapy day case episodes between 1992-3 and 1994-5 was 83%. CONCLUSIONS--The results of this study provide a benchmark both for purchasers and providers of cancer care. The increase in the use of chemotherapy points to an urgent need for a unified system for monitoring both activity and outcomes of treatment.  相似文献   

8.
Material and energy balances for fermentation processes are developed based on the facts that the heat of reaction per electron transferred to oxygen for a wide variety of organic molecules, the number of available electrons per carbon atom in biomass, and the weight fraction carbon in biomass are relatively constant. Mass–energy balance equations are developed which relate the biomass energetic yield coefficient to sets of variables which may be determined experimentally. Organic substrate consumption, biomass production, oxygen consumption, carbon dioxide production, heat evolution, and nitrogen consumption are considered as measured variables. Application of the balances using direct and indirect methods of yield coefficient estimation is illustrated using experimental results from the literature. Product formation is included in the balance equations and the effect of product formation on biomass yield estimates is examined. Application of mass–energy balances in the optimal operation of continuous single-cell protein production facilities is examined, and the variation of optimal operating conditions with changes in yield are illustrated for methanol as organic substrate.  相似文献   

9.
Despite the growing threat of major pandemics, the European Union is planning no more than a meager surveillance agency staffed with 70 people on the 2007 horizon: the new European Centre for Disease Control. I argue that an effective structure should be much larger and include a strong research activity. Asian countries, inspired by the US CDC, are now taking this concept in hand and creating an ASEAN Center For Disease Control, with sophisticated laboratory facilities to be included. This is a tough lesson for us Europeans, and our avarice in this domain could have tragic consequences in the future.  相似文献   

10.
《CMAJ》1985,133(6):598A-598B
It is the position of the Canadian Medical Association (CMA) that family planning advice and assistance should be readily available to all residents of Canada. This is viewed as a responsibility of practising physicians that is to be shared with other health and educational agencies. CMA has recommended the establishment of facilities in addition to physicians'' offices for the dissemination of advice on family planning. These facilities should be developed in consultation with and under the supervision of the medical profession. CMA believes induced abortion should not be an alternative to contraception as a method of responsible family planning. In the event of an unwanted pregnancy, full counselling services should be provided. Within the context of preventive medicine, CMA supports the development of educational programs in family living and the promotion of sex education in the school system by knowledgeable persons sensitive to the needs of students.  相似文献   

11.
Because certain groups at high risk for HIV/AIDS (human immunodeficiency virus/acquired immunodeficiency syndrome) come together in correctional facilities, seroprevalence was high early in the epidemic. The share of the HIV/AIDS epidemic borne by inmates of and persons released from jails and prisons in the United States (US) in 1997 was estimated in a previous paper. While the number of inmates and releasees has risen, their HIV seroprevalence rates have fallen. We sought to determine if the share of HIV/AIDS borne by inmates and releasees in the US decreased between 1997 and 2006. We created a new model of population flow in and out of correctional facilities to estimate the number of persons released in 1997 and 2006. In 1997, approximately one in five of all HIV-infected Americans was among the 7.3 million who left a correctional facility that year. Nine years later, only one in seven (14%) of infected Americans was among the 9.1 million leaving, a 29.3% decline in the share. For black and Hispanic males, two demographic groups with heightened incarceration rates, recently released inmates comprise roughly one in five of those groups'' total HIV-infected persons, a figure similar to the proportion borne by the correctional population as a whole in 1997. Decreasing HIV seroprevalence among those admitted to jails and prisons, prolonged survival and aging of the US population with HIV/AIDS beyond the crime-prone years, and success with discharge planning programs targeting HIV-infected prisoners could explain the declining concentration of the epidemic among correctional populations. Meanwhile, the number of persons with HIV/AIDS leaving correctional facilities remains virtually identical. Jails and prisons continue to be potent targets for public health interventions. The fluid nature of incarcerated populations ensures that effective interventions will be felt not only in correctional facilities but also in communities to which releasees return.  相似文献   

12.
In the past few decades, major advances in environmental protection within the coating application industry have been made. In spite of this technological progress, approximately 50% of industrial-solvent emissions still come from the paint-application sector. The advances made in reducing emissions for plants requiring licensing have unfortunately had no influence on the environmental efforts of smaller companies. Solvent-reduced painting systems, such as high-solid paints, water-based coating, and powder coating have not been able to achieve acceptance, nor have innovative application technologies. The principal arguments against a conversion to these ecologically more favorable alternatives were related to cost and quality.
Recently, the EU Solvent Directive (1999/13/EC) went into effect, aiming to significantly reduce industrial-solvent emissions. Up until this point, however, instruments enabling smaller companies to determine their solvent emissions and to simultaneously develop process-improvement potentials while keeping costs in mind have been missing.
Using the mass and energy flow-management approach, cost structures and environmental benefits can be made transparent to the entrepreneur. The primary result of the research projects presented here is the computer-based mass and energy flow model called the individual computer-aided mass and energy flow model for the vehicle-refinishing sector (IMPROVE). It can be used as a detailed business-consultancy tool. Based upon this, practical guidelines were developed for easy orientation and activity planning. They can be used by companies to help them fulfill the requirements of environmental legislation and to display the benefits that can be achieved by various emission-reduction measures.  相似文献   

13.
In this article we describe an optimization model, a mixed integer program, to determine the optimal locations and capacity sizes of biomass‐based facilities in energy crop supply chains, and demonstrate its use using data for Great Britain. We show the utility of the model for planning the optimal locations of biomass‐based facilities by investigating the supply of feedstock from Miscanthus for Combined Heat and Power (CHP) in Great Britain, based on data of current electricity demand. Results show that CHP cost directly influences its optimal location, and the price of bioelectricity from Miscanthus. At the coarse spatial resolution of the available energy demand data, the sale price of Miscanthus does not greatly influence the quantity of Miscanthus sold in Great Britain. Only when the hypothetical sale price of Miscanthus was closer to CHP cost, was the quantity of Miscanthus sold influenced by the variation in the sale price of Miscanthus. In future, we will apply the model using electricity and heat demand data at fine spatial scale currently being located, which will allow the implications of local production of Miscanthus for CHP to be explored.  相似文献   

14.
Indicators of family planning service access and quality were generated using the Egypt DHS-I (1988) and the Egypt Service Availability Survey (1989), and linked to episodes of contraceptive pill use. Multilevel analysis was used to ascertain whether or not these access and quality indicators influence the continuation of pill use, net of women's socioeconomic, demographic and motivational characteristics. A model with random components at the cluster and women levels was fitted for all reasons of discontinuation, except desire for pregnancy, at 24 months of use. Net of women's background characteristics, the results show that facilities with smaller numbers of health personnel trained in family planning, a lack of access to facilities with female doctors and a lack of range of available methods are associated with a high risk of discontinuation of pill use for all reasons except desire for pregnancy.  相似文献   

15.
A model is presented for calculating the environmental burdens of the part manufacturing and vehicle assembly (VMA) stage of the vehicle life cycle. The model is based on a process‐level approach, accounting for all significant materials by their transformation processes (aluminum castings, polyethylene blow molding; etc.) and plant operation activities (painting; heating, ventilation, and air conditioning [HVAC], etc.) germane to VMA. Using quantitative results for these material/transformation process pairings, a percent‐by‐weight material/transformation distribution (MTD) function was developed that permits the model to be applied to a range of vehicles, both conventional and advanced (e.g., hybrid electric, light weight, aluminum intensive). Upon consolidation of all inputs, the model reduces to two terms: one proportional to vehicle mass and a plant overhead per vehicle term. When the model is applied to a materially well‐characterized conventional vehicle, reliable estimates of cumulative energy consumption (34 gigajoules/vehicle) and carbon dioxide (CO2) emissions (2 tonnes/vehicle) with coefficients of variation are computed for the VMA life cycle stage. Due to the more comprehensive coverage of manufacturing operations, our energy estimates are on the higher end of previously published values. Nonetheless, they are still somewhat underestimated due to a lack of data on overhead operations in part manufacturing facilities and transportation of parts and materials between suppliers and vehicle manufacturing operations. For advanced vehicles, the material/transformation process distribution developed above needs some adjusting for different materials and components. Overall, energy use and CO2 emissions from the VMA stage are about 3.5% to 4.5% of total life cycle values for vehicles.  相似文献   

16.
The effects of mass and age on standard metabolic rate in house crickets   总被引:3,自引:0,他引:3  
Abstract. This study employed flow-through respirometry to measure the oxygen consumption rates (VO2) of inactive male house crickets, Acheta domesticus L. (Orthoptera: Gryllidae), and to quantify the effects of body mass and adult age on standard metabolic rate (SMR). The Vo2 increased with male body mass at a rate similar to that found in other studies of insect aerobic metabolism. The data reported in this study are combined with published data from other species of Orthoptera to generate a consensus allometric relationship between SMR and body mass for the Order. In general, the Orthoptera expend 2–3 times the energy per unit of body mass when inactive as compared to other arthropods, such as tenebrionid beetles, ants and spiders. Possible explanations for this substantial difference are discussed. By contrast to body mass, mass-specific Vo2 decreased with increasing male age. This age effect has previously been reported for mammals but is not well established for insects, and its implications for the preference of cricket females for older mates is discussed. As energy expended for metabolic maintenance comprises 78% of a male cricket's daily energy budget, changes in SMR may have a substantial effect on the energy available for reproduction.  相似文献   

17.
Although peptide mass fingerprinting is currently the method of choice to identify proteins, the number of proteins available in databases is increasing constantly, and hence, the advantage of having sequence data on a selected peptide, in order to increase the effectiveness of database searching, is more crucial. Until recently, the ability to identify proteins based on the peptide sequence was essentially limited to the use of electrospray ionization tandem mass spectrometry (MS) methods. The recent development of new instruments with matrix-assisted laser desorption/ionization (MALDI) sources and true tandem mass spectrometry (MS/MS) capabilities creates the capacity to obtain high quality tandem mass spectra of peptides. In this work, using the new high resolution tandem time of flight MALDI-(TOF/TOF) mass spectrometer from Applied Biosystems, examples of successful identification and characterization of bovine heart proteins (SWISS-PROT entries: P02192, Q9XSC6, P13620) separated by two-dimensional electrophoresis and blotted onto polyvinylidene difluoride membrane are described. Tryptic protein digests were analyzed by MALDI-TOF to identify peptide masses afterward used for MS/MS. Subsequent high energy MALDI-TOF/TOF collision-induced dissociation spectra were recorded on selected ions. All data, both MS and MS/MS, were recorded on the same instrument. Tandem mass spectra were submitted to database searching using MS-Tag or were manually de novo sequenced. An interesting modification of a tryptophan residue, a "double oxidation", came to light during these analyses.  相似文献   

18.
For more than a decade, Midwest Research Institute (MRI) has investigated the effects of exposure to 60 Hz electric and magnetic fields (EMF) on human physiology, performance, and biochemistry. This accumulated experience, new research directions, and limited resources made it important to design more comprehensive and operationally cost-effective exposure facilities. Here we describe the new, integrated laboratory exposure test facilities recently constructed at MRI and present data on relevant characteristics of the exposure systems. Concentric coil systems were developed to generate uniform magnetic fields within the three new exposure rooms, with rapid cancellation of the field to ambient levels in the rest of the laboratory. Control systems are fully automated, computer-based, and independent. These provide the operational flexibility needed to present fields of different magnitudes, frequencies, and polarization. The local geomagnetic field can be modulated and/or canceled, and both AC and DC fields can be presented in various combinations. Capabilities for conducting double-blind experiments with true active-sham exposure conditions were implemented using bifilar windings and applying current flow in the opposite direction for each wire in a pair. The new facilities provide a comprehensive capability for laboratory-based human research on the potential effects of exposure to AC and DC magnetic fields.  相似文献   

19.
The growing trend of employing multiproduct manufacturing facilities along with the randomness inherent in the biopharmaceutical manufacturing environment is creating significant scheduling and planning challenges for the biopharmaceutical industry. This work focuses on capturing the effect of uncertainty in fermentation titers when optimizing the planning of biopharmaceutical manufacturing campaigns. A mixed integer linear programming (MILP) model based on previous work is derived via chance constrained programming (CCP). The methodology is applied to two illustrative examples, and the results are compared with those from the deterministic model and a multiscenario model accompanied by an iterative construction algorithm. The computational results indicate that the proposed methodology offers significant improvements in solution quality over the compared approaches and presents an opportunity for biopharmaceutical manufacturers to make better medium term planning decisions, particularly under uncertain manufacturing conditions.  相似文献   

20.
This paper analyses mass media exposure and its effect on family planning in Bangladesh using data from the Bangladesh Demographic and Health Survey (BDHS) 1993-94. The findings indicate that radio and television are two important mass media for disseminating family planning information in Bangladesh. However, access to them and exposure to family planning through them are still limited. Slightly more than 40% (42.1%) of respondents reported that they had heard family planning messages via radio, while 17.2% said television, 8.4% said poster and 5.4% said billboard. Respondent's place of residence, education, economic status, geographical region and number of living children appeared to be the most important variable determining mass media exposure to family planning. Multivariate analysis shows that both radio and TV exposure to family planning messages and ownership of a radio and TV have a significant effect on current use of family planning methods. These factors remain significant determinants of contraceptive use, even after controlling socioeconomic and demographic factors. The study reveals that both socioeconomic development policies and family planning programmes with a special emphasis on mass media, especially radio, may have a significant effect on contraceptive use in Bangladesh. The principal policy challenge is to design communications strategies that will reach the less privileged, rural and illiterate people who are by far the majority in Bangladesh.  相似文献   

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