Effects of melanin-induced free radicals on the isolated rat peritoneal mast cells

Energy Technology Data Exchange (ETDEWEB)

Ranadive, N.S.; Shirwadkar, S.; Persad, S.; Menon, I.A.

1986-03-01

Pheomelanin from human red hair (RHM) produces considerably more cellular damage in Ehrlich ascites carcinoma cells when subjected to radiations of wavelength 320-700 nm than eumelanin from black hair (BHM). Irradiation of RHM generated large amounts of superoxide while BHM did not produce detectable amounts of superoxide. The present investigations describe the effects of irradiation of mast cells in the presence of various natural and synthetic melanins. Irradiation of mast cells in the presence of RHM and red hair melanoprotein released large amounts of histamine while BHM and synthetic melanins prepared from dopa, cysteinyldopa, or a mixture of dopa and cysteinyldopa did not release histamine. The release of histamine at lower concentrations of RHM was not accompanied by the release of /sup 51/Cr from chromium-loaded cells, suggesting that this release was of noncytotoxic nature. On the other hand, the release of histamine at higher concentrations of RHM was due to cell lysis since both histamine and cytoplasmic marker /sup 51/Cr were released to the same extent. The release evoked by large concentration RHM was not inhibited by superoxide dismutase or catalase. This suggests that the cell lysis under these conditions was not due to H/sub 2/O/sub 2/ or O-2. The finding that mast cells release histamine when irradiated in the presence of RHM suggests that the immediate and late-phase reactions seen in sunburn may in part be due to the release of mediators from these cells.

Impact of human milk pasteurization on the kinetics of peptide release during in vitro dynamic term newborn digestion.

Science.gov (United States)

Deglaire, Amélie; De Oliveira, Samira C; Jardin, Julien; Briard-Bion, Valérie; Emily, Mathieu; Ménard, Olivia; Bourlieu, Claire; Dupont, Didier

2016-07-01

Holder pasteurization (62.5°C, 30 min) ensures sanitary quality of donor's human milk but also denatures beneficial proteins. Understanding whether this further impacts the kinetics of peptide release during gastrointestinal digestion of human milk was the aim of the present paper. Mature raw (RHM) or pasteurized (PHM) human milk were digested (RHM, n = 2; PHM, n = 3) by an in vitro dynamic system (term stage). Label-free quantitative peptidomics was performed on milk and digesta (ten time points). Ascending hierarchical clustering was conducted on "Pasteurization × Digestion time" interaction coefficients. Preproteolysis occurred in human milk (159 unique peptides; RHM: 91, PHM: 151), mostly on β-casein (88% of the endogenous peptides). The predicted cleavage number increased with pasteurization, potentially through plasmin activation (plasmin cleavages: RHM, 53; PHM, 76). During digestion, eight clusters resumed 1054 peptides from RHM and PHM, originating for 49% of them from β-casein. For seven clusters (57% of peptides), the kinetics of peptide release differed between RHM and PHM. The parent protein was significantly linked to the clustering (p-value = 1.4 E-09), with β-casein and lactoferrin associated to clusters in an opposite manner. Pasteurization impacted selectively gastric and intestinal kinetics of peptide release in term newborns, which may have further nutritional consequences. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Peroral endoscopic myotomy achieves similar clinical response but incurs lesser charges compared to robotic heller myotomy.

Science.gov (United States)

Khashab, Mouen A; Kumbhari, Vivek; Tieu, Alan H; El Zein, Mohamad H; Ismail, Amr; Ngamruengphong, Saowanee; Singh, Vikesh K; Kalloo, Anthony N; Clarke, John O; Stein, Ellen M

2017-01-01

Several uncontrolled studies comparing peroral endoscopic myotomy (POEM) and Heller myotomy have demonstrated equivalent short-term efficacy and safety. However, no data exists rergarding the cost of POEM and how it compares to that of robotic Heller myotomy (RHM). The primary aim of this study was to compare the inpatient charges incurred in patients who underwent POEM or RHM for the treatment of achalasia. A retrospective single center review was conducted among 52 consecutive POEM patients (2012-2014) and 52 consecutive RHM patients (2009-2014). All RHM procedures included a Toupet fundoplication and were performed via a transabdominal approach. All POEM procedures were performed by a gastroenterologist in the endoscopy unit. Clinical response was defined by improvement of symptoms and decrease in Eckardt stage to ≤I. All procedural and facility charges were obtained from review of the hospital finance records. There was no difference between POEM and RHM with regards to age, gender, symptom duration, achalasia subtype, manometry findings, or Eckardt symptom stage. There was no significant difference in the rate of adverse events (19.2% vs 9.6%, P = 0.26) or the length of stay (1.9 vs. 2.3, P = 0.18) between both groups. Clinical response rate of patients in the POEM groups was similar to that in the RHM group (94.3% vs. 88.5%, P = 0.48). POEM incurred significantly less total charges compared to LHM ($14481 vs. $17782, P = 0.02). POEM when performed in an endoscopy unit was similar in efficacy and safety to RHM. However, POEM was associated with significant cost savings ($3301/procedure).

Site-Specific Bioconjugation of an Organometallic Electron Mediator to an Enzyme with Retained Photocatalytic Cofactor Regenerating Capacity and Enzymatic Activity

Directory of Open Access Journals (Sweden)

Sung In Lim

2015-04-01

Full Text Available Photosynthesis consists of a series of reactions catalyzed by redox enzymes to synthesize carbohydrates using solar energy. In order to take the advantage of solar energy, many researchers have investigated artificial photosynthesis systems mimicking the natural photosynthetic enzymatic redox reactions. These redox reactions usually require cofactors, which due to their high cost become a key issue when constructing an artificial photosynthesis system. Combining a photosensitizer and an Rh-based electron mediator (RhM has been shown to photocatalytically regenerate cofactors. However, maintaining the high concentration of cofactors available for efficient enzymatic reactions requires a high concentration of the expensive RhM; making this process cost prohibitive. We hypothesized that conjugation of an electron mediator to a redox enzyme will reduce the amount of electron mediators necessary for efficient enzymatic reactions. This is due to photocatalytically regenerated NAD(PH being readily available to a redox enzyme, when the local NAD(PH concentration near the enzyme becomes higher. However, conventional random conjugation of RhM to a redox enzyme will likely lead to a substantial loss of cofactor regenerating capacity and enzymatic activity. In order to avoid this issue, we investigated whether bioconjugation of RhM to a permissive site of a redox enzyme retains cofactor regenerating capacity and enzymatic activity. As a model system, a RhM was conjugated to a redox enzyme, formate dehydrogenase obtained from Thiobacillus sp. KNK65MA (TsFDH. A RhM-containing azide group was site-specifically conjugated to p-azidophenylalanine introduced to a permissive site of TsFDH via a bioorthogonal strain-promoted azide-alkyne cycloaddition and an appropriate linker. The TsFDH-RhM conjugate exhibited retained cofactor regenerating capacity and enzymatic activity.

Remote Health Monitoring Outcome Success Prediction Using Baseline and First Month Intervention Data.

Science.gov (United States)

Alshurafa, Nabil; Sideris, Costas; Pourhomayoun, Mohammad; Kalantarian, Haik; Sarrafzadeh, Majid; Eastwood, Jo-Ann

2017-03-01

Remote health monitoring (RHM) systems are becoming more widely adopted by clinicians and hospitals to remotely monitor and communicate with patients while optimizing clinician time, decreasing hospital costs, and improving quality of care. In the Women's heart health study (WHHS), we developed Wanda-cardiovascular disease (CVD), where participants received healthy lifestyle education followed by six months of technology support and reinforcement. Wanda-CVD is a smartphone-based RHM system designed to assist participants in reducing identified CVD risk factors through wireless coaching using feedback and prompts as social support. Many participants benefitted from this RHM system. In response to the variance in participants' success, we developed a framework to identify classification schemes that predicted successful and unsuccessful participants. We analyzed both contextual baseline features and data from the first month of intervention such as activity, blood pressure, and questionnaire responses transmitted through the smartphone. A prediction tool can aid clinicians and scientists in identifying participants who may optimally benefit from the RHM system. Targeting therapies could potentially save healthcare costs, clinician, and participant time and resources. Our classification scheme yields RHM outcome success predictions with an F-measure of 91.9%, and identifies behaviors during the first month of intervention that help determine outcome success. We also show an improvement in prediction by using intervention-based smartphone data. Results from the WHHS study demonstrates that factors such as the variation in first month intervention response to the consumption of nuts, beans, and seeds in the diet help predict patient RHM protocol outcome success in a group of young Black women ages 25-45.

Ultrastructural changes produced in Ehrlich ascites carcinoma cells by ultraviolet-visible radiation in the presence of melanins

Energy Technology Data Exchange (ETDEWEB)

Lea, P.J.; Pawlowski, A.; Persad, S.D.; Menon, I.A.; Haberman, H.F.

1988-01-01

Irradiation of Ehrlich ascites carcinoma (EAC) cells in the presence of pheomelanin, i.e., red hair melanin (RHM), has been reported to produce extensive cell lysis. Irradiation in the presence of eumelanin, i.e., black hair melanin (BHM), or irradiation in the absence of either type of melanin did not produce this effect. We observed that RHM particles penetrated the cell membrane without apparent structural damage to the cell or the cell membrane. Irradiation of the cells in the absence of melanin did not produce any changes in the ultrastructure of the cells. Incubation of the cells in the dark in the presence of RHM produced only minor structural, mainly cytoplasmic changes. Irradiation of the cells in the presence of RHM produced extensive ultrastructural changes prior to complete cell lysis; these changes were more severe than the effects of incubation of the cells in the dark in the presence of RHM. When the cells incubated in the dark or irradiated in the presence of latex particles or either one of the eumelanins particles, viz. BHM or synthetic dopa melanin, these particles did not penetrate into the cells or produce any ultrastructural changes. These particles were in fact not even ingested by the cells.

Pion photoproduction in the Skyrme model and low-energy theorem

International Nuclear Information System (INIS)

Saito, Sakae; Takeuchi, Fuminaka; Uehara, Masayuki

1993-01-01

We investigate pion photoproduction on the nucleon in the Skyrme model. We employ the formulation, which was recently developed by Hayashi et al., that the full pion field is treated as an interpolating field between asymptotic in and out fields. It is shown that the amplitude of the pion photoproduction is correctly given by the direct and the crossed baryon-pole terms, and the equal-time commutator terms between the axial-vector current and the electromagnetic current and between the pion field and the latter. We show that the lowest-order Kroll-Ruderman and the pion pole terms are reproduced, and that the seagull terms inherent to the Skyrme model are present. Further, the threshold behavior of the amplitude is discussed. (orig.)

High-energy pp and p-barp scattering and the model of geometric scaling

International Nuclear Information System (INIS)

Fischer, J.; Jakes, P.; Novak, M.

1982-10-01

The model of geometric scaling is used to predict the evolution of the diffractive dip-peak structure of pp and p-barp differential cross-sections with increasing energy. Previous calculation for pp scattering made by Dias de Deus and Kroll is carried out with new data and their predictions confirmed. Recent data on p-barp scattering are used to make an analogous analysis for this process as well. It turns out that the p-barp differential cross-section behaves analogously, the main difference being that, in the p-barp case, the dip-peak structure should not completely disappear with increasing energy. (author)

RHM 4.indb

African Journals Online (AJOL)

Jane

to exploring the views of key stakeholders with respect to addressing the topic of .... businesses' reporting on environmental and related (Corporate. Social Responsibility .... identity and strategy of hospitality businesses as the logical next step.

RHM 4.indb

African Journals Online (AJOL)

Jane

Research in Hospitality Management 2014, 4(1&2): 39–44. Printed in The .... But clearly this is not the case – people of different backgrounds ... The concept is often associated .... particular strategies and methodologies, but rather, that all the.

RHM 4.indb

African Journals Online (AJOL)

Jane

Research in Hospitality Management 2014, 4(1&2): 29–37. Printed in .... contextualise the concept of skills within a broader framework pertaining .... important antecedent to strategic purchasing (Ogden et al. 2007). .... The cases were selected ...

RHM 4.indb

African Journals Online (AJOL)

Jane

Research in Hospitality Management 2014, 4(1&2): 13–19. Printed in ... 2011). One of the key strategies used by marketers to allow ... who have an understanding of a restaurant's concept and branding ..... case of McDonald's and Subway.

RHM 4.indb

African Journals Online (AJOL)

Jane

This double issue of Research in Hospitality Management embraces the full ... plan: an investigation of social sustainability: the case of all-inclusive resorts, ... are forced to re-analyse their operational strategies to maintain competitive advantage. ... programme in the hospitality industry: a review of concepts, research, and.

RHM 4.indb

African Journals Online (AJOL)

Jane

Research in Hospitality Management 2014, 4(1&2): 91–95. Printed in The ... this strategic objective. All the same .... concept explaining human eating habits, especially about ... food in cases where other sources of meat are available. Hunting ...

RHM 4.indb

African Journals Online (AJOL)

Jane

Research in Hospitality Management 2014, 4(1&2): 97–104. Printed in The Netherlands ... today's society, fortunately, is no longer the sole case (McClure. 2009). ..... the concepts and theoretical themes as Gehrels found in his research into .... Small Business Service (2003), A strategic framework for women's enterprise.

RHM 4.indb

African Journals Online (AJOL)

Jane

The significance of the growth in joint degree programmes has been ... programmes as a way to offer students international experi- .... context of Bologna (Sursock and Smidt, Trends 2010) joint ... an overseas partner is an example of how institutions can ..... equivalence of experience in educational terms of each institu-.

RHM 4.indb

African Journals Online (AJOL)

Jane

within ethics, as ethical behaviours form the building blocks of human ... it can help us understand the concept of business ethics, commonly ... It is important to adopt a holistic and balanced approach to issues concerning business ethics and.

RHM 4.indb

African Journals Online (AJOL)

Jane

known as the Food and Beverage department and the Rooms. Division department .... not act adequately in unsafe situations, the choice was made to use shocking .... often have no knowledge of their motives does not follow that free will is an ...

RHM 4.indb

African Journals Online (AJOL)

Jane

Academy of Hotel and Facility Management, NHTV Breda University of Applied Sciences, Breda, The Netherlands .... attracting guests, but beyond the bed, many 'budget' hotels ... price charged) but in reality, appealing to more complex.

RHM 4.indb

African Journals Online (AJOL)

Jane

agent to promote the type of social learning that is needed for ... It is part of a wider context, i.e. tourism, in which involved .... to share their views on sustainability, the relevance of sustain- ability for ... network of NHTV's Academy of Hotel Management respec- ... tive or legal pressures than based on an intrinsic motivation to.

RHM 4.indb

African Journals Online (AJOL)

Jane

Research in Hospitality Management 2014, 4(1&2): 45–54. Printed in The .... one organisation can be applied for the benefit of employees in other firms and .... that include various medical, dental, and vision coverage options, as ..... Clinical. Governance: An International Journal 12(3): 178–187. Marriott 2011. Encouraging ...

RHM 4.indb

African Journals Online (AJOL)

Jane

This approach is founded upon deep-rooted ... long-term customer loyalty beyond the somewhat simplistic ... of an instrument that aspires to measure individual hospita- ... the word hospitality has emerged from the shadow of being used to describe a cluster of ..... satisfaction arising from the practice of hospitableness.

RHM 4.indb

African Journals Online (AJOL)

Jane

This very small segment of the Dutch restaurant business (0.2–0.5% of the total ... The transcripts of the recorded interviews were analysed, applying a constructivist grounded theory approach ...... able beforehand about all the contingencies in seeking a ... specific groups of practitioners in the hospitality industry to get more ...

RHM 4.indb

African Journals Online (AJOL)

Jane

for international students considerations include destina- ... skills such as critical thinking, problem solving and interper- sonal skills, but pay ..... people who a job ready', 'when we take people for placement ... Additionally there was a strong.

Radiotoxic hazard measure for buried solid radioactive waste

International Nuclear Information System (INIS)

Hamstra, J.

1975-01-01

The radiotoxic hazards resulting from the disposal of highlevel reprocessing wastes into a deep geological formation are reviewed. The term radiotoxic hazard measure (RHM), used to measure the hazard from buried radioactive wastes, is based on the maximum radionuclide concentration permissible in water. Calculations are made of the RHM levels for the high-level reprocessing wastes of both light-water-reactor and fast breeder reactor fuels. In comparing these RHM levels with that for the natural activity of an equivalent amount of uranium ore and its mill tailings, it is concluded that an actual additional radiotoxic hazard for buried high-level reprocessing waste only exists for the first 300 to 500 years after burial. (U.S.)

Saarbergwerke AG. Report on the business year 1995; Saarbergwerke AG. Bericht ueber das Geschaeftsjahr 1995

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-12-31

The business report 1995 contains informations about the position of the energy economics, the position of the Saarberg trust and the yearly balance. The activities of the Saarberg trust are reported. (RHM) [Deutsch] Der Geschaeftsbericht 1995 enthaelt Ausfuehrungen ueber die Lage der Energiewirtschaft, die Lage des Saarberg-Konzerns und den Jahresabschluss. Die Aktivitaeten des Saarberg-Konzerns werden dargestellt. (RHM)

Comfrey (Symphytum Officinale. l.) and Experimental Hepatic Carcinogenesis: A Short-term Carcinogenesis Model Study.

Science.gov (United States)

Gomes, Maria Fernanda Pereira Lavieri; de Oliveira Massoco, Cristina; Xavier, José Guilherme; Bonamin, Leoni Villano

2010-06-01

Comfrey or Symphytum officinale (L.) (Boraginaceae) is a very popular plant used for therapeutic purposes. Since the 1980s, its effects have been studied in long-term carcinogenesis studies, in which Comfrey extract is administered at high doses during several months and the neoplastic hepatic lesions are evaluated. However, the literature on this topic is very poor considering the studies performed under short-term carcinogenesis protocols, such as the 'resistant hepatocyte model' (RHM). In these studies, it is possible to observe easily the phenomena related to the early phases of tumor development, since pre-neoplastic lesions (PNLs) rise in about 1-2 months of chemical induction. Herein, the effects of chronic oral treatment of rats with 10% Comfrey ethanolic extract were evaluated in a RHM. Wistar rats were sequentially treated with N-nitrosodiethylamine (ip) and 2-acetilaminofluorene (po), and submitted to hepatectomy to induce carcinogenesis promotion. Macroscopic/microscopic quantitative analysis of PNL was performed. Non-parametric statistical tests (Mann-Whitney and χ(2)) were used, and the level of significance was set at P ≤ 0.05. Comfrey treatment reduced the number of pre-neoplastic macroscopic lesions up to 1 mm (P ≤ 0.05), the percentage of oval cells (P = 0.0001) and mitotic figures (P = 0.007), as well as the number of Proliferating Cell Nuclear Antigen (PCNA) positive cells (P = 0.0001) and acidophilic pre-neoplastic nodules (P = 0.05). On the other hand, the percentage of cells presenting megalocytosis (P = 0.0001) and vacuolar degeneration (P = 0.0001) was increased. Scores of fibrosis, glycogen stores and the number of nucleolus organizing regions were not altered. The study indicated that oral treatment of rats with 10% Comfrey alcoholic extract reduced cell proliferation in this model.

A new generation of medium-voltage switchboards and circuit-breakers; Eine neue Generation von Mittelspannungsschaltanlagen und -leistungsschaltern

Energy Technology Data Exchange (ETDEWEB)

Saemann, D.; Weichert, R.; Werner, S. [Siemens AG, Erlangen (Germany). Bereich Energieuebertragung und -verteilung

1998-04-06

Todays market and the trend towards globalization of business both call for new products. The authors describe the new generation of medium-voltage switchgears and circuit-breakers, along with the benefit they bring for customers. (orig./RHM) [Deutsch] Der Markt und die Globalisierung des Geschaeftes fordern neue Produkte. Die Verfasser beschreiben die neue Generation von Mittelspannungsschaltanlagen und -schaltern sowie deren Nutzen fuer die Anwender. (orig./RHM)

Efficacy and durability of robotic Heller myotomy for achalasia: patient symptoms and satisfaction at long-term follow-up.

Science.gov (United States)

Perry, Kyle A; Kanji, Aliyah; Drosdeck, Joseph M; Linn, John G; Chan, Anthony; Muscarella, Peter; Melvin, W Scott

2014-11-01

Laparoscopic Heller myotomy (LHM) has become the standard treatment for achalasia in the USA. Robot-assisted Heller myotomy (RHM) has emerged as an alternative approach due to improved visualization and fine motor control, but long-term follow-up studies have not been reported. We sought to report the long-term outcomes of RHM and compare them to those of LHM. A retrospective cohort study was performed for patients who underwent laparoscopic or RHM between 1995 and 2006. Long-term follow-up was performed via mail or telephone questionnaire. The primary outcome measure was durable relief of dysphagia without need for further intervention. Secondary outcomes included gastroesophageal reflux symptoms, disease-specific quality of life, and patient satisfaction with their operation. Seventy-five patients underwent laparoscopic (n = 19) or robotic (n = 56) myotomy during the study period. Long-term follow-up was obtained in 53 (71 %) patients with a median interval of 9 years. RHM was associated with a decreased mucosal injury rate (0 vs. 16 %, p = 0.01) and median hospital stay (1 vs. 2 days, p myotomy and 80 % after laparoscopic myotomy (p = 0.27). Overall, 95 % of patients were satisfied with their operation, and 91 % would choose surgery again given the benefit of hindsight. There is a dearth of long-term follow-up data to support the effectiveness of RHM. This study demonstrates durable dysphagia relief in the vast majority of patients with a high degree of patient satisfaction and a low rate of esophageal mucosal injury. While a significant proportion of patients report reflux symptoms, these symptoms are well controlled with medical acid suppression.

Possible role of double scattering in electron-atom scattering in a laser field

International Nuclear Information System (INIS)

Rabadan, I.; Mendez, L.; Dickinson, A.S.

1996-01-01

By considering observations of double-scattering effects in the excitation of the 2 1 P level of He, gas density values estimated for the laser-assisted elastic scattering experiments of Wallbank and Holmes (1993, 1994a,b) for which the Kroll-Watson approximation appears to fail. Using comparable densities for He and lower densities for Ar, and assuming the Kroll-Watson approximation for single-scattering events, differential cross sections are calculated including double scattering for laser-assisted scattering for a range of energies and scattering angles. Comparison with the observed values shows that double-scattering effects can give a semi-quantitative explanation of the apparent breakdown of the Kroll-Watson approximation in both He and Ar. (author)

Extended low-frequency approximation for laser-modified electron scattering: Coulomb effects

International Nuclear Information System (INIS)

Mittleman, M.H.

1988-01-01

The Kroll-Watson [N.M. Kroll and K. M. Watson, Phys. Rev. A 8, 804 (1973)] theory for electron scattering in the field of a low-frequency laser has been extended by L. Rosenberg [Phys. Rev. A 23, 2283 (1981); 28, 2727 (1983)] to apply to higher intensities. That result is rederived in another way so as to make the correction second order. The correction terms are obtained and shown to be small in the high-intensity low-energy regime in which the original theory is weakest. The special case of a Coulomb potential is analyzed and shown to present special peculiarities in the extended theory just as in the original Kroll-Watson theory

Climate and transportation; Klima und Verkehr

Energy Technology Data Exchange (ETDEWEB)

Fabian, P. [Muenchen Univ. (Germany). Lehrstuhl fuer Bioklimatologie und Immissionsforschung

1996-06-01

This short contribution discusses emissions of the transportation sector, i.e. the global problem of carbon dioxide emissions and the regional ecological problem of nitric oxide, VOC and CO photosmog emissions. Reduction strategies are discussed. (RHM) [Deutsch] Im vorliegenden, kurzen Beitrag wird auf die Emissionen des Verkehrs, die Emissionen von CO{sub 2} - ein globales Klimaproblem - sowie die Emission von NO{sub x}, VOCs und CO-Photosmog als regionals Umwelt- und Klimaproblem eingegangen. Abschliessend werden Reduktionsstrategien dieskutiert. (RHM)

RHM 1(2).indb

African Journals Online (AJOL)

mike

urban land space and decreasing availability of clean water,. Shanghai's urban .... Typically, passive solar building designs incorporate materials with high thermal ..... the cargo hold or shipping container, the hotel maintains the natural beauty.

RHM 1(1).indb

African Journals Online (AJOL)

mike

Research in Hospitality Management 2011, 1(1): 43–52 ... Innovating concepts are becoming ever ... hospitality industry the concept of employer branding as ... Keywords: employer branding, hospitality industry, human resources management, strategy ..... is not much evidence on employer branding beyond cases.

RHM 1(1).indb

African Journals Online (AJOL)

mike

Research in Hospitality Management 2011, 1(1): 31–35. Printed in South ... perspective of tourism, this research examines the branding strategies of Qatar. To the Qatari, the ... and attempt to present the case of this country through broad description ... In this paper, the dreamland concept forms a framework for reflecting on ...

RHM 1(2).indb

African Journals Online (AJOL)

mike

Research in Hospitality Management 2012, 1(2): 53–63 ... Strategies used to incorporate source materials also remained largely unchanged, with learners ..... score (as is the case in IELTS). ...... Introduction: situating the concept of practice.

RHM 1(2).indb

African Journals Online (AJOL)

mike

the experience of assessing quality in a culinary restaurant setting. .... approaches: 'technical quality/outcome', what the customer ..... of the 'relationship' between price/quality. .... entrepreneurs do not focus enough on the marketing mix and.

RHM 1(1).indb

African Journals Online (AJOL)

mike

(2003) has researched differences in strategic decision making at central ... focused, including a deductive reasoning and an emphasis on the current ... One of the explanations .... based survey (to be found in the appendix), consisting of 20.

RHM 1(1).indb

African Journals Online (AJOL)

mike

e-mail: radumi1971@yahoo.com. Tourism is ... in this study. A second objective was to identify constraints on the project or market failures which would prevent the implementation .... of their attractiveness to tourists from countries such as.

RHM 1(1).indb

African Journals Online (AJOL)

mike

For some time, hospitality has been synonymous with the hotel industry and, ... tion and price reduction strategies, where only large players may be able to survive. ... to provide a clean and safe environment for budget-conscious travellers.

RHM 1(2).indb

African Journals Online (AJOL)

mike

Food. Concern for the planet and intergenerational solidarity was less important for most respondents. ... will be responsive to arguments in favour of the Earth's natural environment. ... Since 2001, China's economy has grown noticeably fast.

RHM 1(1).indb

African Journals Online (AJOL)

mike

An analysis of the development of home exchange organisations ... Keywords: home exchange kernels, hospitality networks, tourism intermediation ..... For the home exchange market, this is clearly the case since ... France. Candidates in more popular regions (e.g. Florence) receive many requests (sometimes five a day) ...

RHM 1(1).indb

African Journals Online (AJOL)

mike

influences of acids, salts, minerals, metals, and irritants. Mouthfeel is ... Coating mouthfeel. Creamy, fatty substances and those containing a significant ... A dry slice of toast. (contracting) will neutralise a slice of smoked salmon (coating).

RHM 1(1).indb

African Journals Online (AJOL)

mike

Do social media display correct conventional hotel ratings? Wouter Hensens*1, Miemie .... tourists are satisfied and delighted to spread positive word of mouth about the destination (World Tourism Organisation,. 2004). Such claims go hand in ...

Accessing word meaning in beginning second language learners: Lexical or conceptual mediation?

NARCIS (Netherlands)

Poarch, G.J.; Hell, J.G. van; Kroll, J.F.

2015-01-01

We tested the predictions of the Revised Hierarchical Model (Kroll & Stewart, 1994) to examine how children map novel words to concepts during early stages of L2 learning. Fifth grade Dutch L2 learners with 8 months of English instruction performed a translation recognition task followed by

A Study Of The Internal Energy And Magnetic Spin Susceptibility Of ...

African Journals Online (AJOL)

An exact approach is re-visited in performing a comparative analysis of the attractive and repulsive 2-D Hubbard model (AHM and RHM respectively) which is used in describing a simplified 2x1 (Cu-O-Cu) lattice (known to play significant role in HTc-superconductivity in cuprates) with the use of the MATLAB. The response ...

Comfrey (Symphytum officinale. L. and Experimental Hepatic Carcinogenesis: A Short-Term Carcinogenesis Model Study

Directory of Open Access Journals (Sweden)

Maria Fernanda Pereira Lavieri Gomes

2010-01-01

Full Text Available Comfrey or Symphytum officinale (L. (Boraginaceae is a very popular plant used for therapeutic purposes. Since the 1980s, its effects have been studied in long-term carcinogenesis studies, in which Comfrey extract is administered at high doses during several months and the neoplastic hepatic lesions are evaluated. However, the literature on this topic is very poor considering the studies performed under short-term carcinogenesis protocols, such as the ‘resistant hepatocyte model’ (RHM. In these studies, it is possible to observe easily the phenomena related to the early phases of tumor development, since pre-neoplastic lesions (PNLs rise in about 1–2 months of chemical induction. Herein, the effects of chronic oral treatment of rats with 10% Comfrey ethanolic extract were evaluated in a RHM. Wistar rats were sequentially treated with N-nitrosodiethylamine (ip and 2-acetilaminofluorene (po, and submitted to hepatectomy to induce carcinogenesis promotion. Macroscopic/microscopic quantitative analysis of PNL was performed. Non-parametric statistical tests (Mann–Whitney and χ2 were used, and the level of significance was set at P ≤ 0.05. Comfrey treatment reduced the number of pre-neoplastic macroscopic lesions up to 1 mm (P ≤ 0.05, the percentage of oval cells (P = 0.0001 and mitotic figures (P = 0.007, as well as the number of Proliferating Cell Nuclear Antigen (PCNA positive cells (P = 0.0001 and acidophilic pre-neoplastic nodules (P = 0.05. On the other hand, the percentage of cells presenting megalocytosis (P = 0.0001 and vacuolar degeneration (P = 0.0001 was increased. Scores of fibrosis, glycogen stores and the number of nucleolus organizing regions were not altered. The study indicated that oral treatment of rats with 10% Comfrey alcoholic extract reduced cell proliferation in this model.

Improving compliance in remote healthcare systems through smartphone battery optimization.

Science.gov (United States)

Alshurafa, Nabil; Eastwood, Jo-Ann; Nyamathi, Suneil; Liu, Jason J; Xu, Wenyao; Ghasemzadeh, Hassan; Pourhomayoun, Mohammad; Sarrafzadeh, Majid

2015-01-01

Remote health monitoring (RHM) has emerged as a solution to help reduce the cost burden of unhealthy lifestyles and aging populations. Enhancing compliance to prescribed medical regimens is an essential challenge to many systems, even those using smartphone technology. In this paper, we provide a technique to improve smartphone battery consumption and examine the effects of smartphone battery lifetime on compliance, in an attempt to enhance users' adherence to remote monitoring systems. We deploy WANDA-CVD, an RHM system for patients at risk of cardiovascular disease (CVD), using a wearable smartphone for detection of physical activity. We tested the battery optimization technique in an in-lab pilot study and validated its effects on compliance in the Women's Heart Health Study. The battery optimization technique enhanced the battery lifetime by 192% on average, resulting in a 53% increase in compliance in the study. A system like WANDA-CVD can help increase smartphone battery lifetime for RHM systems monitoring physical activity.

Asymmetrical Priming Effects: An Exploration of Trilingual German-English-French Lexico-Semantic Memory

Science.gov (United States)

Tytus, Agnieszka Ewa

2017-01-01

The growing number of multilingual speakers poses an interesting question as to the way in which three or more languages are represented in the memory of a language user. The Revised Hierarchical Model (Kroll and Stewart in "J Mem Lang" 33: 149-174, 1994) or the Sense Model (Finkbeiner et al. in "J Mem Lang" 51(1), 1-22, 2004)…

A glossary of terms in measuring and automation engineering

International Nuclear Information System (INIS)

Schruefer, E.

1992-01-01

This German-language glossary has been compiled by cooperative work of more than sixty authors. It contains 1800 terms and their definitions relating to measuring engineering, sensor science and engineering, testing engineering, display and read-out techniques, physical quantities, control systems, fundamentals of control engineering, engineered reliability, process control engineering, robot technology, artificial intelligence and expert systems, simulation and modelling, navigation, electronic and electromechanical components, and microtechnology. (RHM) [de

Changes in nitrogen isotopic compositions during composting of cattle feedlot manure: effects of bedding material type.

Science.gov (United States)

Kim, Young-Joo; Choi, Woo-Jung; Lim, Sang-Sun; Kwak, Jin-Hyeob; Chang, Scott X; Kim, Han-Yong; Yoon, Kwang-Sik; Ro, Hee-Myong

2008-09-01

Temporal changes in delta(15)N of cattle feedlot manure during its composting with either rice hull (RHM) or sawdust (SDM) as bedding materials were investigated. Regardless of the bedding material used, the delta(15)N of total N in the manure increased sharply from +7.6 per thousand to +9.9 per thousand and from +11.4 per thousand to +14.3 per thousand, respectively, in RHM or SDM, within 10 days from the commencement of composting. Such increases could be attributed primarily to N loss via NH(3) volatilization and denitrification based on the very high delta(15)N values (greater than +20 per thousand) of NH(4)(+) and NO(3)(-) in the co-composted manure. The delta(15)N of total N in RHM was substantially lower (by more than 3 per thousand) than that in SDM, suggesting that the delta(15)N of the composted manure was affected not only by N loss but also by the type of bedding material used. Specifically, the higher N concentration in the rice hull than in the saw dust could lead to a greater (15)N isotope dilution.

Energie-Versorgung Schwaben AG. Report on the 57th business year 1995; Energie-Versorgung Schwaben AG. Bericht ueber das 57. Geschaeftsjahr 1995

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-12-31

The present report describes the tasks and activities of one of the German power economy`s large integrated companies which operate large-scale power plants. The 1995 business report disclases extensive financial data (balance, profit and loss account etc.). The purpose of the business is to produce, transmit or transport, respectively, and distribute electricity, long-distance thermal energy, and gas. (RHM) [Deutsch] Es wird eine Beschreibung der Aufgaben und Aktivitaeten dieses grossen Verbundunternehmens und Grosskraftwerksbetreibers der deutschen Elektrizitaetswirtschaft gegeben, wobei der Geschaeftsbericht 1995 zahlreiche finanzielle Daten (Bilanz, Gewinn- u. Verlustrechnung etc.) offenlegt. Der Zweck des Unternehmens ist die Erzeugung, Fortleitung und Verteilung von elektrischem Strom, von Fernwaerme und Gas. (RHM)

Energie-Versorgung Schwaben AG. Report on the 58th business year 1996; Energie-Versorgung Schwaben AG. Bericht ueber das 58. Geschaeftsjahr 1996

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-09-01

The present report describes the tasks and activities of one of the German power economy`s large integrated companies which operate large-scale power plants. The 1996 business report disclases extensive financial data (balance, profit and loss account etc.). The purpose of the business is to produce, transmit or transport, respectively, and distribute electricity, long-distance thermal energy, and gas. (RHM) [Deutsch] Es wird eine Beschreibung der Aufgaben und Aktivitaeten dieses grossen Verbundunternehmens und Grosskraftwerksbetreibers der deutschen Elektrizitaetswirtschaft gegeben, wobei der Geschaeftsbericht 1996 zahlreiche finanzielle Daten (Bilanz, Gewinn- und Verlustrechnung etc.) offenlegt. Der Zweck des Unternehmens ist die Erzeugung, Fortleitung und Verteilung von elektrischem Strom, von Fernwaerme und Gas. (RHM)

Survey of legislation applicable in Germany for implementation of the EC Directive on environmental audits; Ueberblick ueber die in Deutschland fuer die Ausfuehrung der EG-Umwelt-Audit-Verordnung geltenden Rechtsvorschriften

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-06-01

The brochure presents a comprehensive survey of the relevant legislation applicable in Germany to implementation of the EC Directive on environmental auditing. Readers interested in performing such auditing at one glance will find in this compiulation all relevant laws and regulations in full text that are to be observed for implementation of this novel environmental auditing instrument. (orig./RHM) [Deutsch] Diese Broschuere vermittelt einen umfassenden Ueberblick ueber die in Deutschland fuer die Ausfuehrung der EG-Umwelt-Audit-Verordnung geltenden Rechtsvorschriften. Damit wird fuer alle Interessenten ein rascher Zugriff auf die Rechtstexte, die zur praktischen Anwendung des neuartigen Umwelt-Audit-Instruments notwendig sind, ermoeglicht. (orig./RHM)

Impact of human milk pasteurization on gastric digestion in preterm infants: a randomized controlled trial.

Science.gov (United States)

de Oliveira, Samira C; Bellanger, Amandine; Ménard, Olivia; Pladys, Patrick; Le Gouar, Yann; Dirson, Emelyne; Kroell, Florian; Dupont, Didier; Deglaire, Amélie; Bourlieu, Claire

2017-02-01

Holder pasteurization has been reported to modify human milk composition and structure by inactivating bile salt-stimulated lipase (BSSL) and partially denaturing some of its proteins, potentially affecting its subsequent digestion. We sought to determine the impact of human milk pasteurization on gastric digestion (particularly for proteins and lipids) in preterm infants who were fed their mothers' own milk either raw or pasteurized. In a randomized controlled trial, 12 hospitalized tube-fed preterm infants were their own control group in comparing the gastric digestion of raw human milk (RHM) with pasteurized human milk (PHM). Over a 6-d sequence, gastric aspirates were collected 2 times/d before and after RHM or PHM ingestion. The impact of milk pasteurization digestive kinetics and disintegration was tested with the use of a general linear mixed model. Despite inactivating BSSL, instantaneous lipolysis was not affected by pasteurization (mean ± SD at 90 min: 12.6% ± 4.7%; P > 0.05). Lipolysis occurred in milk before digestion and was higher for PHM than for RHM (mean ± SD: 3.2% ± 0.6% and 2.2% ± 0.8%, respectively; P Pasteurization enhanced the proteolysis of lactoferrin (P Pasteurization did not affect gastric emptying (∼30-min half time) or pH (mean ± SD: 4.4 ± 0.8) at 90 min. Overall, pasteurization had no impact on the gastric digestion of lipids and some proteins from human milk but did affect lactoferrin and α-lactalbumin proteolysis and emulsion disintegration. Freeze-thawing and pasteurization increased the milk lipolysis before digestion but did not affect gastric lipolysis. Possible consequences on intestinal digestion and associated nutritional outcomes were not considered in this study. This trial was registered at clinicaltrials.gov as NCT02112331. © 2017 American Society for Nutrition.

Research in Hospitality Management

African Journals Online (AJOL)

Research in Hospitality Management (RHM) is a peer-reviewed journal ... to the quintessential managerial areas of Finance, Human Resources, Operations, ... competency and career development of hospitality management students · EMAIL ...

Hippocampal damage equally impairs memory for single items and memory for conjunctions.

Science.gov (United States)

Stark, Craig E L; Squire, Larry R

2003-01-01

In a prior study of continuous recognition performance, data were reported in support of the hypothesis that the hippocampus is not needed to remember the individual components of a stimulus but is important for remembering associations between its components (Kroll et al. 1996. J Mem Lang 35:176-196). Patients with left hippocampal damage were able to endorse recently encountered words and to reject novel words, as well as disyllabic words in which one of the syllables had been previously encountered. However, they failed to reject words in which both syllables had been encountered independently in different words. We present data from five experiments designed to examine this finding in more detail. In each experiment, five patients with bilateral hippocampal damage and eight controls were tested using the same protocol as Kroll et al. (1996). On each trial, a two-component stimulus was presented. Stimuli could be entirely novel, novel with one previously encountered (repeated) component, novel but with both components repeated, or a true repetition. The first experiment was a direct replication using the same disyllabic words as Kroll et al. (1996). The second experiment used pseudo-words, constructed of two monosyllabic words (e.g., jambark). The third experiment used the same pairs of monosyllabic words, but presented separately on the screen to encourage participants to treat each component independently. The fourth experiment used pairs of objects, and the fifth experiment used face-house pairs. In all five experiments, patients with hippocampal damage exhibited impaired recognition memory. The impairment extended across all trial types with no evidence that hippocampal damage selectively (or disproportionately) impaired the associative or conjunctive component of memory. We discuss our findings in the light of the work by Kroll et al. (1996) and other recent neuropsychological, electrophysiological, and neuroimaging studies of hippocampal function and

Vacuum polarization in Coulomb field revisited

Energy Technology Data Exchange (ETDEWEB)

Zamastil, J., E-mail: zamastil@karlov.mff.cuni.cz; Šimsa, D.

2017-04-15

Simplified derivation of Wichmann–Kroll term is presented. The derivation uses two formulas for hypergeometric functions, but otherwise is elementary. It is found that Laplace transform of the vacuum charge density diverges at zero momentum transfer. This divergence has nothing to do with known ultraviolet divergence. The latter is related to the large momentum behavior of the pertinent integral, while the former to the small momentum behavior. When these divergences are removed, the energy shift caused by vacuum polarization for an ordinary hydrogen obtained here is in an exact agreement with the result obtained by Wichmann and Kroll. Also, for muonic hydrogen the result obtained here reasonably agrees with that given in literature.

Fotografia e fetiche: um olhar sobre a imagem da mulher Photography and fetish: a glance at women's image

Directory of Open Access Journals (Sweden)

Mariana Meloni Vieira Botti

2003-01-01

Full Text Available Este artigo investiga a imagem da mulher fetichizada, socialmente construída enquanto objeto de desejo. Através da análise de imagens dos fotógrafos Elmer Batters, Eric Kroll e Cristiano, buscando decodificar alguns elementos simbólicos do universo do fetiche, e interpretar a construção de seus significados a partir de questões de gênero.This article investigates the image of fetishized women, socially constructed as an object of desire. Analyzing the images of photographers Elmer Batters, Eric Kroll and Cristiano, it decodes the symbolic elements of the fetishist universe, and intends to interpret its constructions and meanings concerning gender issues.

Obstetrics and Gynaecology Forum - Vol 21, No 2 (2011)

African Journals Online (AJOL)

Review: Robot assisted laparoscopic surgery in gynaecological oncology · EMAIL FULL TEXT EMAIL FULL TEXT DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. RHM Verheijen. http://dx.doi.org/10.4314/ogf.v21i2.66899 ...

A comparison of high velocity systems on rail. Cooperation project. Pt. 2/A. Final report. A method to evaluate operating costs. Vergleich von spurgefuehrten Hochgeschwindigkeitssystemen. Kooperationsprojekt. T. 2/A. Abschlussbericht. Comparaison de systemes de transport guide a grande vitesse. Projet de cooperation. Pt. 2/A. Rapport final. Methode zur Bestimmung der Betriebskosten. Methode de determination des couts d'exploitation

Energy Technology Data Exchange (ETDEWEB)

1990-01-01

In this German-French cooperation project a comparison between the high speed Intercity Express (ICE), the high speed train TGV (train a grande vitesse) and the maglev rapid transit system Transrapid is drawn. Investment costs for infrastructure and rail network and operating costs, ie costs for the operational management, maintenance and capital cost are compared. For this a method has been worked out for the calculation of operating cost ratios and a model has been developed for writing operating programmes and for the evaluation of operating costs. (RHM).

Hirabayashi, Satoshi; Kroll, Charles N.; Nowak, David J. 2011. Component-based development and sensitivity analyses of an air pollutant dry deposition model. Environmental Modelling & Software. 26(6): 804-816.

Science.gov (United States)

Satoshi Hirabayashi; Chuck Kroll; David Nowak

2011-01-01

The Urban Forest Effects-Deposition model (UFORE-D) was developed with a component-based modeling approach. Functions of the model were separated into components that are responsible for user interface, data input/output, and core model functions. Taking advantage of the component-based approach, three UFORE-D applications were developed: a base application to estimate...

Modeling and multidimensional optimization of a tapered free electron laser

Directory of Open Access Journals (Sweden)

Y. Jiao

2012-05-01

Full Text Available Energy extraction efficiency of a free electron laser (FEL can be greatly increased using a tapered undulator and self-seeding. However, the extraction rate is limited by various effects that eventually lead to saturation of the peak intensity and power. To better understand these effects, we develop a model extending the Kroll-Morton-Rosenbluth, one-dimensional theory to include the physics of diffraction, optical guiding, and radially resolved particle trapping. The predictions of the model agree well with that of the GENESIS single-frequency numerical simulations. In particular, we discuss the evolution of the electron-radiation interaction along the tapered undulator and show that the decreasing of refractive guiding is the major cause of the efficiency reduction, particle detrapping, and then saturation of the radiation power. With this understanding, we develop a multidimensional optimization scheme based on GENESIS simulations to increase the energy extraction efficiency via an improved taper profile and variation in electron beam radius. We present optimization results for hard x-ray tapered FELs, and the dependence of the maximum extractable radiation power on various parameters of the initial electron beam, radiation field, and the undulator system. We also study the effect of the sideband growth in a tapered FEL. Such growth induces increased particle detrapping and thus decreased refractive guiding that together strongly limit the overall energy extraction efficiency.

Reliable Radiation Hybrid Maps: An Efficient Scalable Clustering-based Approach

Science.gov (United States)

The process of mapping markers from radiation hybrid mapping (RHM) experiments is equivalent to the traveling salesman problem and, thereby, has combinatorial complexity. As an additional problem, experiments typically result in some unreliable markers that reduce the overall quality of the map. We ...

Reverse hypothesis machine learning a practitioner's perspective

CERN Document Server

Kulkarni, Parag

2017-01-01

This book introduces a paradigm of reverse hypothesis machines (RHM), focusing on knowledge innovation and machine learning. Knowledge- acquisition -based learning is constrained by large volumes of data and is time consuming. Hence Knowledge innovation based learning is the need of time. Since under-learning results in cognitive inabilities and over-learning compromises freedom, there is need for optimal machine learning. All existing learning techniques rely on mapping input and output and establishing mathematical relationships between them. Though methods change the paradigm remains the same—the forward hypothesis machine paradigm, which tries to minimize uncertainty. The RHM, on the other hand, makes use of uncertainty for creative learning. The approach uses limited data to help identify new and surprising solutions. It focuses on improving learnability, unlike traditional approaches, which focus on accuracy. The book is useful as a reference book for machine learning researchers and professionals as ...

Suri fetishismi isa

Index Scriptorium Estoniae

1999-01-01

New Yorgis suri kunstnik ja koomiksite joonistaja, pärastsõja-aegse Ameerika bondage-erootika illustraator Eric Stanton. Paar aastat tagasi avaldas Saksa kirjastus Taschen Stantoni elust ja loomingust raamatu, mille toimetas erootikafotograaf Eric Kroll

The production phase model as a tool for analysing and structuring the database of an operation management system; Das Phasenmodell der Produktion als ein Werkzeug fuer Analyse und Strukturierung der Datenbasis eines Betriebsmanagementsystems

Energy Technology Data Exchange (ETDEWEB)

Rauprich, G.; Polke, B.

1997-12-31

This paper presents a process analysis which was carried out with the aid of a phase model for the purpose of supporting the start-up phase of an operation management system. Beside providing a functional structure for the database this process analysis permits a functional and consistent representation of the process at as crude or detailed a level as desired. In this way the phase model supplies a functional model of the process which serves the purposes of both the process control and the operation control level. Once the phase model has been created it largely only depends on the question being asked which level of detail and what properties of the relevant process elements and material and energy flows are used. [Deutsch] Eine mit Hilfe des Phasenmodells durchgefuehrte Prozessanalyse unterstuetzt die Einfuehrungsphase eines Betriebsmanagementsystems. Sie gibt eine funktionale Struktur der Datenbank vor und erlaubt darueberhinaus auf der Ebene des Betriebsmanagementsystems eine funktionale, konsistente, beliebig grobe oder feine detaillierte Darstellung des Prozesses. Die Phasenmodellierung liefert damit sowohl fuer die Prozessleitebene als auch fuer die Betriebsleitebene ein ganzheitliches, funktionales Modell des Prozesses. Wenn das Phasenmodell erst einmal erstellt ist, ist es im wesentlichen nur abhaengig von der Fragestellung, welche Detaillierungsebenen mit welchen Eigenschaften der relevanten Prozesselemente und Material-/Energiestroeme verwendet werden. (orig./RHM)

Energy and climate policy in Europe; Energie- und Klimapolitik in Europa

Energy Technology Data Exchange (ETDEWEB)

NONE

2011-07-01

This is a publication of the Baden-Wuerttemberg state center of political education (Landeszentrale fuer Politische Bildung Baden-Wuerttemberg) on energy policy and climate policy in Europe. It discusses the following aspects: Assured supply of energy and climate policy - incompatible goals? Climate policy and energy policy in a global system; Legitimation of the EU by successful energy policy and climate policy; Emission trading: Selling of indulgences or successful instrument? Energy policy in Europe after 1945; From a beacon of hope to a phase-out model? The future of nuclear power; The future of renewable energy sources in Europe. (orig./RHM)

Development of curricula for the deregulated energy industry, as illustrated by the example of electric power supply in Germany; Curriculumentwicklung fuer die liberalisierte Energiewirtschaft - dargestellt am Beispiel der Stromversorgung in Deutschland

Energy Technology Data Exchange (ETDEWEB)

Krah, Nils

2011-07-01

This monography provides an expert and also didactic analysis of the electric power industry and presents a model for constructing practice-oriented curricula for the grid-bound power industry, both for different target groups and for different educational levels (occupational and academic). The book also demonstrates how the method can be applied for concrete definition of goals, contents and schedules for vocational training and for the development of an effective teaching methodology by the teacher. The analyses that are presented also provide a basis for discussions among experts of the energy industry and its further development. (orig./RHM)

Controlling applied to information processing: quality management applied to IP projects and IP services; Informationsverarbeitungs-Controlling: Qualitaetsmanagement fuer IV-Projekte und fuer IV-Service

Energy Technology Data Exchange (ETDEWEB)

Becker, B. [Vereinigung Deutscher Elektrizitaetswerke e.V. (VDEW), Frankfurt am Main (Germany); Beckers, F. [Isar-Amperwerke AG, Muenchen (Germany); Dewald, N. [Bayernwerk AG, Muenchen (Germany); Hauffe, P. [Pfalzwerke AG, Ludwigshafen am Rhein (Germany); Hein, F. [EVS AG Stuttgart (Germany); Hoederath, M. [Vereinigte Elektrizitaetswerke Westfalen AG (VEW), Dortmund (Germany); Seyen, R. [Staedtische Werke Nuernberg GmbH (Germany)

1998-01-12

The working group on information processing (IP) basics (in German: `IV-Grundlagen`) has prepared this contribution dealing with controlling applied to information processing. This new report, on the one hand, takes into consideration the role of the organizational IP unit as one offering its services to all sections of a company. On the other hand, information processing as an operational infrastructure influencing all business processes becomes increasingly important with respect to the competitiveness of the EVU. Therefore, quality management applied to IP projects and IP services must support this development. (orig./RHM) [Deutsch] Der VDEW Arbeitskreis `IV-Grundlagen` hat einen Beitrag zum Controlling fuer die Informationsverarbeitung erstellt. Hier geht zum einen die Rolle der Organisationseinheit IV als Dienstleister fuer alle Unternehmensbereiche ein. Zum anderen gewinnt die Informationsverarbeitung als betriebliche Infrastruktur fuer alle Geschaeftsprozesse zunehmende Bedeutung fuer die Wettbewerbsfaehigkeit der EVU. Das Qualitaetsmanagement fuer IV-Projekte und fuer IV-Service muss dies unterstuetzen. (orig./RHM)

The production of wear protection coatings reinforced with tungsten carbide by temperature-controlled welding with the CO{sub 2} laser; Herstellung wolframkarbidverstaerkter Verschleissschutzschichten durch temperaturgeregeltes Auftragschweissen mit dem CO{sub 2}-Laser

Energy Technology Data Exchange (ETDEWEB)

Nowotny, S.; Boddin, G.C.; Luft, A.; Techel, A. [Fraunhofer-Inst. fuer Werkstoffphysik und Schichttechnologie, Dresden (Germany); Uelze, A. [Hochschule fuer Technik und Wirtschaft Dresden (Germany)

1995-12-31

Protective coatings can be produced by laser coating with metal alloys reinforced by carbide, whose resistance to abrasive wear with a content of 40 to 50% by volume of hard material is comparable to sintered TC-Co hard metal. Due to the remaining ductile material behaviour and the metallurgical binding to the substrate, the coatings have high impact, fatigue and adhesion strengths. The use of process control leads to a stable coating process and to increased safety and reproduceability when working in narrow parameter areas. (orig./RHM) [Deutsch] Durch das Laserbeschichten mit karbidverstaerkten Metallegierungen koennen Schutzschichten erzeugt werden, deren Widerstand gegen Abrasivverschleiss bereits bei einem Hartstoff-Volumengehalt von 40 bis 50% gesintertem WC-Co-Hartmetall vergleichbar ist. Aufgrund des verbleibenden duktilen Werkstoffverhaltens und der metallurgischen Bindung zum Substrat verfuegen die Schichten ueber hohe Schlag-, Ermuedungs- und Haftfestigkeiten. Der Einsatz der Prozessregelung fuehrt zu einem stabilen Beschichtungsvorgang und zu einer erhoehten Sicherheit und Reproduzierbarkeit beim Arbeiten in eng begrenzten Parameterbereichen. (orig./RHM)

Swiss electricity statistics 1996

International Nuclear Information System (INIS)

1997-01-01

This detailed article discusses the following subjects: Survey of electricity supply in Switzerland in 1996; The Swiss electricity balance; Electric power generation; Electric power consumption; Generation, consumption and loads on selected days; Energy trade with other countries; Expansion capacities until 2003; Financial situation and appendix. (orig./RHM) [de

Development of Metamaterial Composites for Compact High Power Microwave Systems and Antennas

Science.gov (United States)

2016-05-01

Silva Neto, L.P.; de Siqueira, R.H.M. "Study of the ceramic capacitor dielectric for pulsed power", Pulsed Power Conference (PPC), 2013 19th IEEE...47 5.3.5 Barium Titanate Ferrite Composites ................................................................. 50 6. Dielectric ...Strength Measurement ..................................................................................... 59 6.1 Design of Pulsed Dielectric Breakdown

Deutsche Shell AG. Annual report 1997

International Nuclear Information System (INIS)

1998-01-01

This annual report of Deutsche Shell AG reflects its activities in the sector natural gas, mineral oil, chemicals and renewable energies. Environmental protection, safety at work, and the position of the group in society are further subjects. Financial data of 1997 are presented (balance sheet, profit-and-loss account,etc.). (orig./RHM) [de

Climate protection after Copenhagen. International instruments and national implementation. Proceedings; Klimaschutz nach Kopenhagen. Internationale Instrumente und nationale Umsetzung. Tagungsband

Energy Technology Data Exchange (ETDEWEB)

Gundel, Joerg; Lange, Knut Werner (eds.)

2011-07-01

The publication contains the results of the First Bayreuth Energy Law Days on the subject of 'Climate Protection after Copenhagen'. Following the UN climate conference of December 2009, it presents the current state of discussion of the legal instruments of climate protection on an international, European and national level. (orig./RHM)

Higher order mode damping studies on the PEP-II B-Factory RF cavity

International Nuclear Information System (INIS)

Rimmer, R.; Goldberg, D.; Lambertson, G.; Voelker, F.; Ko, K.; Kroll, N.; Pendleton, R.; Schwarz, H.; Adams, F.; De Jong, M.

1992-03-01

We describe studies of the higher-order-mode (HOM) properties of the prototype 476 MHz RF cavity for the proposed PEP-II B-Factory and a waveguide damping scheme to reduce possible HOM-driven coupled-bunch beam instability growth. Numerical studies include modelling of the HOM spectrum using MAFIA and ARGUS, and calculation of the loaded Q's of the damped modes using data from these codes and the Kroll-Yu method. We discuss briefly the experimental investigations of the modes, which will be made in a full-size low-power test cavity, using probes, wire excitation and bead perturbation methods

Some remarks on electron scattering in a laser field

International Nuclear Information System (INIS)

Ehlotzky, F.

1988-01-01

Potential scattering of electrons in a quantized radiation field is reconsidered. Some remarks are made on the validity of the Kroll-Watson scattering formula and on the close connection of this formula with the classical transition rate of scattering in a radiation field. (17 refs.)

e.on. Annual report 2010; e.on. Geschaeftsbericht 2010

Energy Technology Data Exchange (ETDEWEB)

NONE

2011-07-01

In 2010, E.ON sold 1030 thousand million kWh of electricity and 1342 thousand million kWh of gas. The annual report contains a detailed management report, the annual consolidated financial statement, the corporate governance report, information on the board of directors and corporate management, as well as tables and explanations. (orig./RHM)

Regional energy supply in 1994/1995. Progress report of the working pool of regional power supply companies (ARE e.V.); Regionale Energieversorgung 1994/1995. Taetigkeitsbericht der Arbeitsgemeinschaft regionaler Energieversorgungs-Unternehmen - ARE - e.V

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-04-01

Generally speaking the present report deals with the regional power supply as part of the whole economy. In this connection it also addresses issues of economic development. The following topics are covered in its report on the activities of ARE since the annual meeting of 1994; energy policy, regional supply in the new Laender, European common market for electricity, energy-economic law, special provisions under cartel law concerning public utilities. The report concludes with a description of the organisation of ARE (tasks and aims, members, executive board, management, committees, headquarters). (RHM) [Deutsch] Gegenstand des Berichtes ist zunaechst die regionale Energieversorgung im Rahmen der Gesamtwirtschaft. Dabei wird sowohl auf die wirtschaftliche Entwicklung als auf die regionale Energieversorgung eingegangen. Anschliessend wird ein Ueberblick ueber die Taetigkeit des ARE seit der Jahrestagung 1994 gegeben. Dabei werden Aktivitaeten in den Bereichen Energiepolitik, Regionalversorgung in den neuen Bundeslaendern, europaeischer Binnenmarkt fuer Elektrizitaet, Energiewirtschaftsrecht sowie kartellrechtlicher Ausnahmebereich Versorgungswirtschaft behandelt. Abschliessend wird die Organisation der ARE (Aufgaben und Ziele, Mitglieder, Vorstand, Geschaeftsfuehrung, Ausschuesse, Geschaeftsstelle) beschrieben. (RHM)

Regional energy supply in 1996/1997. Progress report of the working pool of regional power supply companies (ARE e.V.); Regionale Energieversorgung 1996-1997. Taetigkeitsbericht der Arbeitsgemeinschaft regionaler Energieversorgungs-Unternehmen - ARE - e.V

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-04-01

Generally speaking the present report deals with the regional power supply as part of the whole economy. In this connection it also addresses issues of economic development. The following topics are covered in its report on the activities of ARE since the annual meeting of 1996; energy policy, regional supply in the new Laender, European common market for electricity and natural gas, energy-economic law, special provisions under cartel law concerning public utilities. The report concludes with a description of the organisation of ARE (tasks and aims, members, executive board, management, committees, headquarters). (RHM) [Deutsch] Gegenstand des Berichtes ist zunaechst die regionale Energieversorgung im Rahmen der Gesamtwirtschaft. Dabei wird sowohl auf die wirtschaftliche Entwicklung als auf die regionale Energieversorgung eingegangen. Anschliessend wird ein Ueberblick ueber die Taetigkeit des ARE seit der Jahrestagung 1996 gegeben. Dabei werden Aktivitaeten in den Bereichen Energiepolitik, Regionalversorgung in den neuen Bundeslaendern, europaeischer Binnenmarkt fuer Elektrizitaet und Gas, Energiewirtschaftsrecht sowie kartellrechtlicher Ausnahmebereich Versorgungswirtschaft behandelt. Abschliessend wird die Organisation der ARE (Aufgaben und Ziele, Mitglieder, Vorstand, Geschaeftsfuehrung, Ausschuesse, Geschaeftsstelle) beschrieben. (RHM)

Obtention of titanium and zirconium metallic

International Nuclear Information System (INIS)

Santos, P.R.G.; Rover, C.F.S.; Amaral, F.L.L.

1988-01-01

The development works of techniques and equipments for titanium and zirconium sponges obtention are mentioned. The Kroll Process used for the sponges production is described, consisting in the reduction of the metal tetracloride with magnesium in an inert atmosphere of helium or argon. (C.G.C.) [pt

Dictionary of centrifugal pumps. 3. rev. ed. Kreiselpumpen Lexikon

Energy Technology Data Exchange (ETDEWEB)

Holzenberger, K; Jung, K [comps.

1989-01-01

This technical dictionary was brought up to date of the state of the art. The terminology was supplemented with terms referring to centrifugal pumps. There are now almost 700 terms, with their English and French translations. To facilitate usage all the terms of books are listed in alphabetical order at the end of the book. (RHM).

Stress Management for Sport.

Science.gov (United States)

Zaichkowsky, Leonard D., Ed.; Sime, Wesley E., Ed.

Included in this volume are papers on stress management in athletics; eight of the ten papers are followed with a "Coach's Reaction": (1) "Competitive Athletic Stress Factors in Athletes and Coaches" (Walter Kroll); (2) "Mental Preparation for Peak Performance in Swimmers" (Eugene F. Gauron)--Coach's Reaction by Suzi…

Reader Engagement in English and Persian Applied Linguistics Articles

Science.gov (United States)

Ansarin, Ali Akbar; Tarlani-Aliabdi, Hassan

2011-01-01

There is an increasing interest in the way academic writers establish the presence of their readers over the past few years. Establishing the presence of readers or what Kroll (1984, p.181) calls imagining "a second voice" is accomplished when a writer refers "explicitly" to their readers using explicit linguistic resources…

How we promote renewable energies. Financing aids, examples, contacts

International Nuclear Information System (INIS)

1996-08-01

The present brochure informas the reader on possibilities of promotion and financing aids for renewable energies in Germany. In order to facilitate his understanding of the prinicpal technologies eligible for promotion it briefly describes the special features of the relevant technologies in an easily understandable manner. At the end the reader will find useful addresses and literature references. (orig./RHM) [de

Applications of tensor functions in creep mechanics

International Nuclear Information System (INIS)

Betten, J.

1991-01-01

Within this contribution a short survey is given of some recent advances in the mathematical modelling of materials behaviour under creep conditions. The mechanical behaviour of anisotropic solids requires a suitable mathematical modelling. The properties of tensor functions with several argument tensors constitute a rational basis for a consistent mathematical modelling of complex material behaviour. This paper presents certain principles, methods, and recent successfull applications of tensor functions in solid mechanics. The rules for specifying irreducible sets of tensor invariants and tensor generators for material tensors of rank two and four are also discussed. Furthermore, it is very important that the scalar coefficients in constitutive and evolutional equations are determined as functions of the integrity basis and experimental data. It is explained in detail that these coefficients can be determined by using tensorial interpolation methods. Some examples for practical use are discussed. (orig./RHM)

Technical and marketing aspects of power use in industry and trade; Technik- und Marketingaspekte bei der industriellen und gewerblichen Stromanwendung

Energy Technology Data Exchange (ETDEWEB)

Mann, E.W.; Duenkelberg, R.

1997-02-01

Using electric power permits energetic optimization of production processes in industry and trade. Because of the trend towards qualitatively high-grade products, the energy form electric power plays a key role. Increased power demand on the part of industrial customers coincides with increased competition in the energy supply sector at the national and international levels. Within short, therefore, these industrial customers may prompt a change in preferences at the supplier side. Utilities will adopt suitable marketing concepts in order to gain profile with their customers as service providers. Operating close to customers will essentially influence customer satisfaction and, thereby, customer loyalty. (orig./RHM) [Deutsch] Durch die Stromanwendung koennen Produktionsprozesse in Industrie und Gewerbe energetisch optimiert werden. Bei dem Trend zu qualitativ hochwertigen Produkten nimmt die Energieform Strom eine Schluesselstellung ein. Die erhoehte Stromnachfrage der Industriekunden trifft auf zunehmenden Wettbewerb bei der Energieversorgung auf nationaler und internationaler Ebene, wodurch in Kuerze Industriekunden andere Praeferenzen bei den Energielieferanten setzen koennen. Durch geeignete Marketingkonzepte werden sich die Energieversorgungsunternehmen (EVU) als Energiedienstleister ihrer Kunden profilieren. Die Naehe zum Kunden wird wesentlich die Kundenzufriedenheit und damit letztlich auch die Kundenloyalitaet beeinflussen. (orig./RHM)

Energy report 1995 for Schleswig-Holstein. Situation, focal areas, examples; Energiebericht Schleswig-Holstein 1995. Situation, Schwerpunkte, Beispiele

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-09-01

Since 1988 the Land of Schleswig Holstein has been going new ways in its energy policy. Its declared aims are energy saving in heat and electricity supply, efficient energy utilisation, a greater utilisation of renewable energy resources, and, of principal importance, the phase-out of nuclear energy. As the legislative competence of the Laender is very restricted in matters relating to energy, the new policy has primarily been designed as a means of demonstrating by way of example that there actually are considerable potentials for saving energy and that they can be exploited. The present report gives an overview of the results of Schleswig Holstein`s energy policy of the last seven years. (orig./RHM) [Deutsch] Seit 1988 geht das Land Schleswig-Holstein energiepolitisch neue Wege. Das erklaerte Ziel: Energieeinsparung im Waerme- und Strombereich, rationelle Energieverwendung, staerkere Nutzung erneuerbarer Energien. Und grundsaetzlich: Ausstieg aus der Kernenergie. Da die Bundeslaender nur ueber eine sehr eingeschraenkte Gesetzgebungskompetenz im Energiebereich verfuegen, zielte die neue Energiepolitik zunaechst darauf ab, durch Foerderprogramme beispielhaft zu zeigen, dass tatsaechlich erhebliche Einsparpotentiale bestehen und auch umsetzbar sind. Der Bericht gibt einen Ueberblick ueber die Ergebnisse der Energiepolitik der letzten sieben Jahre in Schleswig-Holstein. (orig./RHM)

World Bank support for renewable energy - the ASTAE experience

International Nuclear Information System (INIS)

Schaeffer, L.

1999-01-01

Historically, the World Bank has helped finance the generation, transmission and distribution of electricity as well as improvements in supply-side energy efficiency. The World Bank's ability to mainstream renewable energy technologies in developing countries is enhanced by the Global Energy Facility (GEF), the World Bank Solar Initiative (and the nascent Solar Development Corporation), the International Finance Corporation and the Asia Alternative Energy Unit (ASTAE). (orig./RHM)

The Unsinkable Aircraft Carrier - An American Response to the Chinese Anti-Access/Area Denial (A2/AD) Challenge

Science.gov (United States)

2013-04-01

DISTRIBUTION /AVAILABILITY STATEMENT Approved for public release; distribution unlimited 13. SUPPLEMENTARY NOTES 14. ABSTRACT 15. SUBJECT TERMS 16...new Nike -Hercules missile batteries. 121 The idea of an active defense against missiles has been disregarded by some because the necessary... Nike -Hercules) Defends Northern Taiwan 1958-1959.” http://www.2-71adataiwan.com/Member%20Articles/RHM%20Deployment%20Article.htm 122 Martin

Synthesis of zirconium by zirconium tetrachloride reduction by magnesio-thermia. Experimental study and modelling

International Nuclear Information System (INIS)

Basin, N.

2001-01-01

This work deals with the synthesis of zirconium. The ore is carbo-chlorinated to obtain the tetrachloride which is then purified by selective condensation and extractive distillation. Zirconium tetrachloride is then reduced by magnesium and the pseudo-alloy is obtained according to the global following reaction (Kroll process): ZrCl 4 + 2 Mg = 2 MgCl 2 . By thermodynamics, it has been shown that the volatilization of magnesium chloride and the formation of zirconium sub-chlorides are minimized when the combined effects of temperature and of dilution with argon are limited. With these conditions, the products, essentially zirconium and magnesium chloride, are obtained in equivalence ratio in the magnesio-thermia reaction. The global kinetics of the reduction process has been studied by a thermal gravimetric method. A thermo-balance device has been developed specially for this kinetics study. It runs under a controlled atmosphere and is coupled to a vapor tetrachloride feed unit. The transformation is modelled supposing that the zirconium and magnesium chloride formation result: 1)of the evaporation of magnesium from its liquid phase 2)of the transfer of magnesium and zirconium tetrachloride vapors towards the front of the reaction located in the gaseous phase 3)of the chemical reaction. In the studied conditions, the diffusion is supposed to be the limiting process. The influence of the following parameters: geometry of the reactive zone, temperature, scanning rate of the argon-zirconium tetrachloride mixture, composition of the argon-zirconium tetrachloride mixture has been experimentally studied and confronted with success to the model. (O.M.)

Balanced scorecard - a novel management philosophy; Balanced scorecard - eine neue Management-Philosophie

Energy Technology Data Exchange (ETDEWEB)

Pendzialek, W.

1999-09-20

The article briefly explains the management philosophy elaborated by Kaplan and Norton, USA. (orig./CB) [German] Bei dem von Kaplan und Norton in den USA entwickelte Managementkonzept der Balanced Scorecard wird eine Uebergewichtung der finanziellen Ergebnisse verhindert. Es wird eine Ausgewogenheit zwischen langfristigen und kurzfristigen Zielen, monetaeren und nichtmonetaeren Kennzahlen, Spaet- und Fruehindikatoren sowie internen und externen Leistungsanforderungen angestrebt. Dies fuehrt zu einer vernetzten und multidimensionalen Betrachtungsweise. (orig./RHM)

World Bank support for renewable energy - the ASTAE experience

Energy Technology Data Exchange (ETDEWEB)

Schaeffer, L. [World Bank, Washington, DC (United States). Asia Alternative Energy Unit

1999-07-01

Historically, the World Bank has helped finance the generation, transmission and distribution of electricity as well as improvements in supply-side energy efficiency. The World Bank's ability to mainstream renewable energy technologies in developing countries is enhanced by the Global Energy Facility (GEF), the World Bank Solar Initiative (and the nascent Solar Development Corporation), the International Finance Corporation and the Asia Alternative Energy Unit (ASTAE). (orig./RHM)

Mobility at any cost? Necessity and limits. Pt. 1; Mobilitaet um jeden Preis? Notwendigkeit und Grenzen. T. 1

Energy Technology Data Exchange (ETDEWEB)

Assmann, G. [comp.; Froese, B. [comp.; Haury, H.J. [comp.; Jahn, T. [comp.

1996-06-01

On 27 June 1996, the `Information Umwelt` organisation held a seminar for journalists in Munich under the title `Mobility at any cost? Necessity and limits`. In industrial societies, mobility is defined as a basic need. The contributions compiled in the present volume are basically transcripts of the lectures held at the meeting. Their titles are as follows: Mobility for tomorrow - problems, requirements,possible solutions; California dreaming? - new framework conditions for tomorrow`s mobility; Mobility as a success strategy - who falls by the wayside?; Climate and transport; Pollutants from road traffic and breathing trouble in children; Transport development in a developing country: The example of the People`s Republic of China; The fuel cell in mobile use. (orig/RHM) [Deutsch] `Mobilitaet um jeden Preis? Notwendigkeit und Grenzen` hiess das Thema des Journalistenseminars, das die Information Umwelt am 27.6.1966 in Muenchen veranstaltete. Mobilitaet wird in der Industriegesellschaft als Grundbeduerfnis definiert. Bei den Beitraegen handelt es sich im wesentlichen um schriftliche Ausarbeitungen der Referenten zu den Themen: Mobilitaet fuer morten - Probleme, Anforderungen, Loesungsansaetze; California Dreaming? - Neue Rahmenbedingungen fuer die Mobilitaet von morgen; Erfolgsprinzip Fortbewegung - wer bleibt auf der Strecke?; Klima und Verkehr; Schadstoffe aus dem Strassenverkehr; Verkehrsentwicklung in einem Entwicklungsland - Das Beispiel der Volksrepublik China; Die Brennstoffzelle im mobilen Einsatz. (orig./RHM)

76 FR 58319 - Order Granting Temporary Exemption of Kroll Bond Rating Agency, Inc. From the Conflict of...

Science.gov (United States)

2011-09-20

... Exchange Act of 1934 (``Exchange Act'') prohibits a nationally recognized statistical rating organization... traditionally has operated mainly under the ``subscriber-paid'' business model, in which the NRSRO derives its... Act'') as set forth in the Report of the Senate Committee on Banking, Housing, and Urban Affairs...

Energy management problems from a business oriented and engineering oriented view; Energiewirtschaftliche Fragestellungen aus betriebswirtschaftlicher und ingenieurwissenschaftlicher Sicht

Energy Technology Data Exchange (ETDEWEB)

Felden, Carsten (ed.) [TU Bergakademie Freiberg (Germany). Fakultaet fuer Wirtschaftswissenschaften

2009-07-01

The publication comprises seven contributions, most of them written by staff members of TU Bergakademie Freiberg University. Their titles are: Unbundling from the perspective of accountancy; Balancing of emission rights according to IFRS in public utilities; Portfolio design and energy trade; Development of a strategic perspective for the development of a mining company; IT unbundling at Stadtwerke Duesseldorf AG; Control circuit based workplaces in mining; New products development; Project scheduling with design iterations. (orig./RHM)

Influence of rolling and annealing conditions on texture and mechanical properties of zirconium (1960); Influence des conditions de laminage et de recuit sur la texture et les proprietes mecaniques du zirconium (1960)

Energy Technology Data Exchange (ETDEWEB)

Orssaud, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1958-06-15

Rolling and annealing textures of KROLL zirconium samples at several rolling rates were studied by pole figures with an automatic recorder versus the position in the sheet thickness. Tensile tests, hardness measurements and micrographic examinations allowed to study the evolution of the recrystallization and the variation of the mechanical properties after rolling and/or annealing. Annealing textures slightly varies with the annealing temperature. Annealing at 500 deg. C gives several peculiarities. This temperature seems characteristic in the study of zirconium. (author) [French] Les textures de laminage et de recuit d'echantillons de zirconium KROLL lamine a divers taux ont ete etudiees en tracant des diagrammes de figures de poles en divers points de l'epaisseur des toles, a l'aide d'un appareil a enregistrement automatique. Des essais de traction et des mesures de duretes ainsi que des micrographies ont permis de suivre l'evolution de la recristallisation et les variations des caracteristiques mecaniques au divers stades du laminage et du recuit. La texture de recuit parait varier avec la temperature utilisee. De nombreuses particularites qui apparaissent apres recuit vers 500 deg. C montrent l'importance de cette zone de temperature dans l'etude du zirconium. (auteur)

Not the market allowing to quickly pocket money. Siemens/KWU and their commitments in Central and Eastern Europe

International Nuclear Information System (INIS)

Schwegmann, P.

1997-01-01

After the break-up of the Eastern Bloc, Siemens very soon concluded strategic alliances with the big and most qualified Russian power plant manufacturers, busy activities currently focusing on the nuclear sector with retrofitting and safety engineering work in a number of NPPs. Points of main interest are systems analysis, recurrent inspection of primary loop components, and the installation of diagnostic systems for operational monitoring, as well as the instrumentation and control systems. (Orig./RHM) [de

Better uses for financial reserves. Reserves for decommisioning, dismantling and waste management could be used for changing energy sructures

International Nuclear Information System (INIS)

Irrek, W.

1996-01-01

The reserves laid back by German operators of nuclear power plants for decommissioning, dismantling and waste management amounted to more than DM 44 billion in 1994, and the sum is still increasing. With this money, the public utilities intend to strengthen their competitive position in other industrial sectrors. The author proposes to transfer this money into public funds instead in order to ensure that it is used in an economically more efficient manner. (orig./RHM) [de

Radiation hybrid mapping of genes in the lithium-sensitive wnt signaling pathway.

Science.gov (United States)

Rhoads, A R; Karkera, J D; Detera-Wadleigh, S D

1999-09-01

Lithium, an effective drug in the treatment of bipolar disorder, has been proposed to disrupt the Wnt signaling pathway. To facilitate analysis of the possible involvement of elements of the Wnt pathway in human bipolar disorder, a high resolution radiation hybrid mapping (RHM) of these genes was performed. A fine physical location has been obtained for Wnt 7A, frizzled 3, 4 and 5, dishevelled 1, 2 and 3, GSK3beta, axin, alpha-catenin, the Armadillo repeat-containing genes (delta-catenin and ARVCF), and a frizzled-like protein (frpHE) using the Stanford Human Genome Center (SHGC) G3 panel. Most of these genes were previously mapped by fluorescence in situ hybridization (FISH). Frizzled 4, axin and frpHE did not have a previous chromosomal assignment and were linked by RHM to chromosome markers, SHGC-35131 at 11q22.1, NIB1488 at 16p13.3 and D7S2919 at 7p15.2, respectively. Interestingly, some of these genes were found to map within potential regions underlying susceptibility to bipolar disorder and schizophrenia as well as disorders of neurodevelopmental origin. This alternative approach of establishing the precise location of selected genetic components of a candidate pathway and determining if they map within previously defined susceptibility loci should help to identify plausible candidate genes that warrant further analysis through association and mutational scanning.

The radiation destruction of blood compatible blockcopolymers

International Nuclear Information System (INIS)

Gorelik, B.A.; Raygorodsky, I.M.; Dubinskaya, O.V.; Goldberg, E.Sh.; Listvoyb, G.I.

1991-01-01

Among the blood compatible polymers such blockcopolymers as polyurethanes and polycarbonatesiloxanes the main problem of the production is the method of sterilization. It is considered that the radiation sterilization promising for articles like catheters made from these polymers. There are some data in the literature about radiation stability of polycarbonates and polysiloxane, but the influence of ionizing irradiation on polycarbonatesiloxane was not studied until now. The irradiation was carried out by γ-cell RHM-γ-20 in air. (author) 4 refs.; 5 figs

Ethics: A Selected Bibliography.

Science.gov (United States)

1985-03-01

Morality and Beyond. New York: Harper & Row, 1963. (BJ1251 T6) 291. TolstoY, Lev N. Tolstoy’s Writings on Civil Disobedience and Non- Violence . 0 New York...Translated by R.H.M. Elwes. New York: Philosophi- cal Library, 1957. (B3973 E5E4) 265. Stack, George J. Kierkegaard’s Existential Ethics. University: Univer...271. Storer, Morris B., ed. Humanist Ethics: Dialogue on Basics. Buffalo: Prometheus Books, 1980. (BJ1360 1185) /4. Stratford, Michael C. Political

Kroll, Murakami, and Seneviratne Receive 2013 James B. Macelwane Medals: Response

Science.gov (United States)

Seneviratne, Sonia I.

2014-01-01

Thank you, Niki, for this very kind citation. Not only are you generous in your support, you are also an outstanding and inspiring scientist as well as a great colleague at ETH Zurich. I would also like to thank all those who supported my nomination and AGU's Macelwane committee for choosing me for this great honor. This means a lot to me: The first scientific conference I ever attended was organized by AGU and gave me a lasting motivation to work in science.

Zircon Carburation Studies as Intermediate Stage in the Zirconium Fabrication; Estudios encaminados a la carburacion del circon como etapa intermedia en la obtencion de circonio

Energy Technology Data Exchange (ETDEWEB)

Almagro Huertas, V; Saenz de Tejada Gonzalez, L.; Lopez Rodriguez, M

1963-07-01

Zirconium carbide and carbonitride mixtures were obtained by Kroll's method.Reaction products have been identified by micrography and X-ray diffraction analysis. The optimum graphite content in the initial charge for the carburation reaction has been studied. zirconium, silicon and carbon content in the final product has been controlled as a function of current in the furnace and reaction time.Further chlorination of the final product was performed successfully. (Author) 16 refs.

Zircon Carburation Studies as Intermediate Stage in the Zirconium Fabrication

International Nuclear Information System (INIS)

Almagro Huertas, V.; Saenz de Tejada Gonzalez, L.; Lopez Rodriguez, M.

1963-01-01

Zirconium carbide and carbonitride mixtures were obtained by Kroll's method.Reaction products have been identified by micrography and X-ray diffraction analysis. The optimum graphite content in the initial charge for the carburation reaction has been studied. zirconium, silicon and carbon content in the final product has been controlled as a function of current in the furnace and reaction time.Further chlorination of the final product was performed successfully. (Author) 16 refs

Zircon Carburation Studies as Intermediate Stage in the Zirconium Fabrication; Estudios encaminados a la carburacion del circon como etapa intermedia en la obtencion de circonio

Energy Technology Data Exchange (ETDEWEB)

Almagro Huertas, V.; Saenz de Tejada Gonzalez, L.; Lopez Rodriguez, M.

1963-07-01

Zirconium carbide and carbonitride mixtures were obtained by Kroll's method.Reaction products have been identified by micrography and X-ray diffraction analysis. The optimum graphite content in the initial charge for the carburation reaction has been studied. zirconium, silicon and carbon content in the final product has been controlled as a function of current in the furnace and reaction time.Further chlorination of the final product was performed successfully. (Author) 16 refs.

Nondestructive density measured in powder metallurgy and ceramics

International Nuclear Information System (INIS)

Schlieper, G.; Arnold, V.; Dirkes, H.

1989-01-01

Absorption measurements with gamma radiation have been utilized for the determination of porosities (densities) in materials compacted or sintered from metallic or ceramic powders. The mathematical background for the assessment of this method, and for evaluations of the accuracy of measurement is presented within the reported paper. The equipment for the practical application of density measurements in industry has been developed. Hardware and software of this computerized instrument are designed for a maximum of safety, ease of operation, reliability, flexibility, and efficiency. (orig./RHM) [de

Universitaet der Bundeswehr Hamburg. Research Report 1986-1988. Universitaet der Bundeswehr Hamburg. Forschungsbericht 1986-1988

Energy Technology Data Exchange (ETDEWEB)

Strauch, P.; Dietrich, B. (comps.)

1989-01-01

The report covers the years 1986/87/88. It reports on R and D results from four faculties: electrical engineering, mechanical engineering, pedagogics, and economic and industrial organization sciences. Beyond the obligation to report, the research report is also part of a general concept which is to foster the transfer of know-how and technology between university and industry. It is made known that in 1987 Artificial Intelligence and Computer Integrated Manufacturing were taken up as focal points, the chairs cooperating on an interdisciplinary basis. (orig./RHM).

Automation of hydro power on the upper Rhine and modernization of a power station at the confluence of the Rhine and Aare rivers; Automatisierung der Wasserwirtschaft am Hochrhein und Modernisierung eines Kraftwerkes am Zusammenfluss von Aare und Rhein

Energy Technology Data Exchange (ETDEWEB)

Beltzig, C.; Schlageter, G.

1996-12-31

For the first barrage weir after the confluence of the Rhine and Aare rivers, a maximum storage level is determined and set that constitutes an operating optimum and takes the different inflow and outfall volumes as well as existing retention capacities into account. Moreover, the process control system ensures automatic operation of the three engine units of the power station including process control of the barrage weir and the external systems belonging to the Albbruck-Doggern hydroelectric power station on the Rhine (RADAG). (orig./RHM)

Quantum chemical modeling of perovskite: An investigation of piezoelectricity in ferrite of yttrium.

Science.gov (United States)

de Lira, Fábio Augusto M; Farias, Márcio de Souza; de Figueiredo, Antonio Florêncio; Gil, Fábio dos Santos; dos Santos, Marcos Antonio B; Malheiros, Bruno Veiga; Ferreira, João Elias V; Pinheiro, José Ciríaco; Treu-Filho, Oswaldo; Kondo, Rogério Toshiaki

2011-07-01

In a previous article, we used Hartree-Fock (HF) theory to study the piezoelectricity in BaTiO₃. In this paper, we applied the Douglas-Kroll-Hess second order scalar relativistic method to investigate the possible piezoelectric properties in the perovskite YFeO₃ structure, which has not yet been studied experimentally. The 30s20p13d and 31s21p17d Gaussian basis sets for the Fe (⁵D) and Y (²D) atoms, respectively, were built with the Generator Coordinate HF method. After contraction to [13s7p5d] and [13s8p7d], in combination with the 20s14p/6s4p basis set for the O (³P) atom from literature, they had their quality evaluated using calculations of the total and the orbital energies for the ²FeO⁺¹ and ¹YO⁺¹ fragments. The dipole moment, the total energy, and the total atomic charges in YFeO₃ in C(s) space group were calculated. The results and the analysis lead us to believe that the perovskite YFeO₃ does not present piezoelectric properties.

Opportunities in the electrowinning of molten titanium from titanium dioxide

CSIR Research Space (South Africa)

Van Vuuren, DS

2005-10-01

Full Text Available used, the following forms of titanium are produced: titanium sponge, sintered electrode sponge, powder, molten titanium, electroplated titanium, hydride powder, and vapor-phase depos- ited titanium. Comparing the economics of alter- native...-up for producing titanium via the Kroll process is approximately as follows: ilmenite ($0.27/kg titanium sponge); titanium slag ($0.75/kg titanium sponge); TiCl4 ($3.09/kg titanium sponge); titanium sponge raw materials costs ($5.50/kg titanium sponge); total...

In search of low cost titanium: the fray farthing chen (FFC) cambridge process

CSIR Research Space (South Africa)

Oosthuizen, SJ

2011-03-01

Full Text Available delivering a sponge product, aimed at replacing Kroll sponge alone, does not have potential for large reduction in overall titanium cost. Significant cost savings can be achieved only by also reducing the large number of process steps required... to process the sponge to mill product, including sponge purification, comminution, electrode forming, vacuum arc re-melting, and hot and cold rolling. Presently, economy of scale in the production of titanium dictates that it is most cost...

Retrofitting of power plants. Chances and partnerships; Kraftwerksmodernisierung. Moeglichkeiten und Partnerschaften

Energy Technology Data Exchange (ETDEWEB)

Bald, A. [Siemens AG, Bereich Energieerzeugung (KWU), Erlangen (Germany); Schwegmann, P. [Siemens AG, Bereich Energieerzeugung (KWU), Erlangen (Germany)

1997-01-01

Thousands of power plant managers in the former Soviet Union and the COMECON countries were compelled in the last few years to make a virtue of necessity, adopting the slogan that says ``necessity is the mother of invention`` in their efforts to keep their power plants operating, although there was no way of getting spare sparts or assistance from the general planning boards in Moscow; due to their improvisatory skills they accomplished a great achievement and managed to maintain electricity supply to date. However, the resulting situation today is that the great majority of power plants in the former COMECON member states, i. e in the CIS and in Central and East Europe, badly need repair and backfitting. The article discusses chances and potentials of power plant retrofitting activities, cooperative activities on the part of western countries, and financial support programmes. (orig./RHM) [Deutsch] Tausende von Kraftwerksdirektoren in der ehemaligen Sowjetunion und in den RGW-Staaten haben aus der Not eine Tugend machen muessen: Mit Improvisation und Flexibilitaet hielten sie ihre Kraftwerke am Laufen - Hilfe und Ersatzteile waren von den zentralen Planungsstellen in Moskau kaum zu erwarten; es war eine ungeheure Leistung, dass die Stromversorgung ueberhaupt noch aufrechterhalten wurde. Als Ergebnis dieser Zwangslage sind die meisten Kraftwerke im ehemaligen RGW-Raum, dem heutigen Mittel-Osteuropa und der GUS, dringend ueberholungsbeduerftig. Moeglichkeiten der Kraftwerksmodernisierung, Kooperationen bei der Rekonstruktion und Fragen der Finanzierung werden im folgenden erlaeutert. (orig./RHM)

Model analysis of secondary organic aerosol formation by glyoxal in laboratory studies: the case for photoenhanced chemistry.

Science.gov (United States)

Sumner, Andrew J; Woo, Joseph L; McNeill, V Faye

2014-10-21

The reactive uptake of glyoxal by atmospheric aerosols is believed to be a significant source of secondary organic aerosol (SOA). Several recent laboratory studies have been performed with the goal of characterizing this process, but questions remain regarding the effects of photochemistry on SOA growth. We applied GAMMA (McNeill et al. Environ. Sci. Technol. 2012, 46, 8075-8081), a photochemical box model with coupled gas-phase and detailed aqueous aerosol-phase chemistry, to simulate aerosol chamber studies of SOA formation by the uptake of glyoxal by wet aerosol under dark and irradiated conditions (Kroll et al. J. Geophys. Res. 2005, 110 (D23), 1-10; Volkamer et al. Atmos. Chem. Phys. 2009, 9, 1907-1928; Galloway et al. Atmos. Chem. Phys. 2009, 9, 3331- 306 3345 and Geophys. Res. Lett. 2011, 38, L17811). We find close agreement between simulated SOA growth and the results of experiments conducted under dark conditions using values of the effective Henry's Law constant of 1.3-5.5 × 10(7) M atm(-1). While irradiated conditions led to the production of some organic acids, organosulfates, and other oxidation products via well-established photochemical mechanisms, these additional product species contribute negligible aerosol mass compared to the dark uptake of glyoxal. Simulated results for irradiated experiments therefore fell short of the reported SOA mass yield by up to 92%. This suggests a significant light-dependent SOA formation mechanism that is not currently accounted for by known bulk photochemistry, consistent with recent laboratory observations of SOA production via photosensitizer chemistry.

Green capitalism? Global climate change, global competition between states, and the prevention of the energy turnaround; Gruener Kapitalismus? Klimawandel, globale Staatenkonkurrenz und die Verhinderung der Energiewende

Energy Technology Data Exchange (ETDEWEB)

Rest, Jonas

2011-07-01

Transnational groups call for green capitalism as well as the governments of leading states. In spite of this, international climate conferences are failing, and CO2 emissions are ever-increasing. A climate catastrophe that will threaten the lives of millions is getting increasingly probable. The book states that green capitalism will be impossible unless the power of fossil industries can be broken. These industries are among the strongest and best-organized capital groups and have decisive relevance for the competition strategies of the most powerful states of the world. (orig./RHM)

Renewable energy sources and electromobility. Financial obstacles to market introduction by 2020; Erneuerbare Energien und Elektromobilitaet. Finanzielle Huerden zur Markteinfuehrung bis 2020

Energy Technology Data Exchange (ETDEWEB)

Mayer, Joerg; Muehlenhoff, Joerg

2010-06-15

This publication of the ''Agentur fuer Erneuerbare Energien'' describes why electromobility is a good thing and then proceeds to go into the financial needs of electric vehicles. Four scenarios of differential cost calculation are discussed, and conclusions are drawn for sustainable market introduction. Finally, the following questions are discussed: What is the climate protection effect of 1 million electric vehicles? How much of imported fossil fuels can be saved by 1 million electric vehicles? Is there enough power supply capacity? How can electric vehicles support the grid integration of renewable energy sources? (RHM)

Obtaining mutants of Streptomyces griseoflavus strain 1339, producers of glucose isomerase, following gamma irradiation

International Nuclear Information System (INIS)

Dzhedzheva, G.; Stoeva, N.; Stojchev, M.

1990-01-01

A water suspension of Streptomyces griseoflavus strain 1339 spores of a density of 8.7.10 6 spores/cm 3 is gamma irradiated ( 60 Co, RHM-γ-20, 30.3 Gy/min). The survival of Streptomyces griseoflavus strain 1339 spores was determined depending on radiation doses, exposure times and incubation temperature. Five major morphological types of colonies were isolated, characterized by different levels of glucose isomerase activity. Maximum specific glucose isomerase activity (GIU/g) was attained after the third gamma irradiation step using a dose of 3000 Gy. 2 tabs., 3 figs., 7 refs

Promoting renewables through soft loans

International Nuclear Information System (INIS)

Marcks, C.

1999-01-01

The DtA, founded in 1950s, is a federal institution owned by the German government. It assists the government to implement its economic, environmental and social policy. Financial assistance is being granted mainly through soft loans. Such loans are a flexible instrument, permitting to partially correct prices without severely distorting market forces. They assure total financing while spreading the subsidy over the entire period of the engagement. This avoids windfall opportunities often related to direct subsidies. Investors, therefore, have an intrinsic motivation to only submit sound and profitable projects. (orig./RHM)

Synthesis of zirconium by zirconium tetrachloride reduction by magnesio-thermia. Experimental study and modelling; Elaboration de zirconium par reduction de tetrachlorure de zirconium par magnesothermie. Etude experimentale et modelisation

Energy Technology Data Exchange (ETDEWEB)

Basin, N

2001-01-01

This work deals with the synthesis of zirconium. The ore is carbo-chlorinated to obtain the tetrachloride which is then purified by selective condensation and extractive distillation. Zirconium tetrachloride is then reduced by magnesium and the pseudo-alloy is obtained according to the global following reaction (Kroll process): ZrCl{sub 4} + 2 Mg = 2 MgCl{sub 2}. By thermodynamics, it has been shown that the volatilization of magnesium chloride and the formation of zirconium sub-chlorides are minimized when the combined effects of temperature and of dilution with argon are limited. With these conditions, the products, essentially zirconium and magnesium chloride, are obtained in equivalence ratio in the magnesio-thermia reaction. The global kinetics of the reduction process has been studied by a thermal gravimetric method. A thermo-balance device has been developed specially for this kinetics study. It runs under a controlled atmosphere and is coupled to a vapor tetrachloride feed unit. The transformation is modelled supposing that the zirconium and magnesium chloride formation result: 1)of the evaporation of magnesium from its liquid phase 2)of the transfer of magnesium and zirconium tetrachloride vapors towards the front of the reaction located in the gaseous phase 3)of the chemical reaction. In the studied conditions, the diffusion is supposed to be the limiting process. The influence of the following parameters: geometry of the reactive zone, temperature, scanning rate of the argon-zirconium tetrachloride mixture, composition of the argon-zirconium tetrachloride mixture has been experimentally studied and confronted with success to the model. (O.M.)

In search of low cost titanium: the Fray Farthing Chen (FFC) Cambridge process

CSIR Research Space (South Africa)

Oosthuizen, SJ

2010-10-01

Full Text Available delivering a sponge product, aimed at replacing Kroll sponge alone, does not have potential for large reduction in overall titanium cost. Significant cost savings can only be achieved by also reducing the large number of process steps required to process... the sponge to mill product, including sponge purification, comminution, electrode forming, Vacuum Arc Re-melting, Hot and cold rolling. Presently, economy of scale in the production of titanium dictates that it is most cost effective to cast the largest...

Influence of rolling and annealing conditions on texture and mechanical properties of zirconium (1960)

International Nuclear Information System (INIS)

Orssaud, J.

1958-06-01

Rolling and annealing textures of KROLL zirconium samples at several rolling rates were studied by pole figures with an automatic recorder versus the position in the sheet thickness. Tensile tests, hardness measurements and micrographic examinations allowed to study the evolution of the recrystallization and the variation of the mechanical properties after rolling and/or annealing. Annealing textures slightly varies with the annealing temperature. Annealing at 500 deg. C gives several peculiarities. This temperature seems characteristic in the study of zirconium. (author) [fr

Operation planning for a pondage power station chain by means of linear programming and genetic optimisation; Einsatzplanung fuer eine Flusskraftwerkskette im Schwellbetrieb mittels LP und genetischer Optimierung

Energy Technology Data Exchange (ETDEWEB)

Mueller, H.; Huelsemann, M.

1997-12-31

This paper presents a system package which serves as a simulation and optimisation tool for daily operation planning for a hydroelectric cascade. The purpose of the planning is to maximise (the differentially weighted) production of electrical energy given a certain set of specifications and secondary conditions. Optimal operation management is achieved using a two-stage approach: first pre-optimisation by means of linear programming, followed by detail optimisation using a Genetic Algorithm based on a non-linear, dynamic model of the power station and reservoir chain. [Deutsch] Im Beitrag wird ein Systempaket als Simulations- und Optimierungswerkzeug zur taeglichen Betriebsplanung einer Wasserkraftwerkskaskade vorgestellt. Ziel der Wasserbewirtschaftung ist es, unter den gegebenen Vorgaben und Randbedingungen die (bewertete) Erzeugung elektrischer Energie zu maximieren. Das optimale Fahrplanmanagement wird durch einen zweistufigen Loesungsansatz realisiert: Mit einer Vor-Optimierung mittels Linearer Programmierung (LP), gefolgt von einer detaillierten Optimierung mit einem Genetischen Algorithmus, der auf ein nichtlineares, dynamisches Simulationsmodell fuer die Kette aus Kraftwerken und Stauraeumen zugreift. (orig./RHM)

Quality of energy consultancy services - Requirements, criteria for evaluation, and a case report; Energieberatungsqualitaet - Anforderungen, Messung und ein Fallbeispiel

Energy Technology Data Exchange (ETDEWEB)

Hausser, K.

1999-07-01

The article initially pictures an optimized model of energy consultancy and continues with explaining an instrument available for quality assessment of services in general, (SERVQUAL), presenting approaches for modifying this tool so as to make it applicable to evaluating the quality of energy consultancy activities. Finally, the capabilities of the modified tool are discussed referring to a case study in an electric utility, the Neckarwerke Stuttgart. (orig./CB) [German] Energieberatung durch Energieversorgungsunternehmen wird in Deutschland fast flaechendeckend angeboten. Im Beitrag wird zuerst aufgezeigt, welche Anforderungen eine optimale Energieberatung erfuellen muss. Danach wird ein Instrument vorgestellt, das die Qualitaet von Dienstleistungen im allgemeinen misst und im Rahmen der o.g. Arbeit so weiterentwickelt wurde, dass es von nun an auch als Instrument zur Messung der Qualitaet von Energieberatung im Besonderen dienen kann: SERVQUAL (von SERVice QUALity). Zuletzt werden die Ergebnisse praesentiert, die in der o.g. Untersuchung unter Anwendung von SERVQUAL bei den Neckarwerken Stuttgart erzielt wurden. (orig./RHM)

Forecasting market developments

International Nuclear Information System (INIS)

Weller, T.

1997-01-01

Traditional planning in essence consists of linear extrapolation of established facts and experience. This approach was good enough until recently, when progress would be relatively foreseeable within a stable system. The situation has been changing with developments and modifications in the global economic sector proceeding at accelerated pace, so that conventional planning methods become hopelessly inadequate. The past is of low significance to emerging markets; planners today have to keep abreast with and take into account the possible and emerging influencing factors. Experience is a factor to be replaced by intelligent analysis and conclusion within the framework of system networks. Modern scenario modelling methods are based on this approach: They are able to simulate and forecast a whole range of ''possible futures'', derived from perceivable trends. The article illustrates the novel planning methodology by assessing the future of the renewable energy sources, applying a computerized planning method (vision design) which is based on intelligent comparative analysis of all relevant trends. (Orig./RHM) [de

Report of Research at Technische Universitaet Darmstadt on Ultrahard Materials in the B-C-N-Si System

Science.gov (United States)

2015-06-01

Thin Solid Films. 1999;354(1– 2):148. 171. Horvath -Bordon E, Riedel R, McMillan PF, Kroll P, Miehe G , van Aken PA, Zerr A, Hoppe P, Shebanova O...that B is significantly more stable than A. .................................41 Fig. 2.11 g -C3N4: s-triazine-based chemical structure and TEM image of...sulfate as the catalyst (SigmaUltra, ≥99.0%, Sigma-Aldrich, Germany; 32.90 Euros for 100 g ) as shown in Scheme 1. 1 2 3 Scheme 1 The

Are affective events richly recollected or simply familiar? The experience and process of recognizing feelings past.

Science.gov (United States)

Ochsner, K N

2000-06-01

The author used the remember/know paradigm and the dual process recognition model of A. P. Yonelinas, N. E. A. Kroll, I. Dobbins, M. Lazzara, and R. T. Knight (1998) to study the states of awareness accompanying recognition of affective images and the processes of recollection and familiarity that may underlie them. Results from all experiments showed that (a) negative stimuli tended to be remembered, whereas positive stimuli tended to be known; (b) recollection, but not familiarity, was boosted for negative or highly arousing and, to a lesser extent, positive stimuli; and (c) across experiments, variations in depth of encoding did not influence these patterns. These data suggest that greater recollection for affective events leads them to be more richly experienced in memory, and they are consistent with the idea that the states of remembering and knowing are experientially exclusive, whereas the processes underlying them are functionally independent.

Computation of Propagation Speed and Reflection of Axially Symmetric Waves in Composite Cylinders, with Application to Impedance Tube and Calibrator.

Science.gov (United States)

1982-08-25

hoth real and complex; and () compute the propagation speed in the acoustic cal Ibr:ator. (continued on reverse) DD IARM3 1473 EDITION OF I NOVSSIS...FORMAT (3F15.0) 0131 GO TO 230 0132 690 CONTINUE 0133 END 50 *> SUBROUTINES SUBROUTINE: DET C C SUBROUTINE DET C DECEMBER, 1980 C EDITED BY TINA RUGGIERO...33 AISA =AKDA/BAMS 0008 02A=AKA**’-AKDA**2 0009 S2A=AKA**2-AKSA**2 0010 IF (RHM) 65P65P40 0011 40 AKFA-AKDA/COCD 0012 OF2A-AKA**2-AKFA**2 0013 IF (OF2A

Emission certificates. Legal, tax-related and practical aspects; Emissionszertifikate. Rechtliche, steuerliche und praktische Aspekte

Energy Technology Data Exchange (ETDEWEB)

Hack, Christoph; Bartholl, Carsten; Hartmann, Astrid (eds.)

2011-07-01

The book discusses the issue of emission certificates from the view of public law, civil law and tax law, in consideration of practical experience with emission reduction projects. The subjects discussed range from emission trading from the view of public law to the civil law and regulatory law aspects of emission trading and taxation law. The legal situation in Germany is covered from the view of public and private law. The state of legislation on emission reduction in the USA is gone into, and practical experience relating to the Clean Development Mechanism is presented. (orig./RHM)

My own Agenda 21 - My personal energy conservation scheme; Meine Agenda 21 - Energiesparbuch

Energy Technology Data Exchange (ETDEWEB)

Kregel, V. [ed.

1999-04-01

The title of this booklet imitates the name of the action programme Agenda 21, which has been adopted in 1992 at the UN conference on environment and development, also called the Rio de Janeiro Earth Summit, where the international community of states agreed to forthwith follow the paradigm of ''sustainable development''. (orig./CB) [German] Der Titel unseres Energiesparbuchs lehnt sich an das Aktionsprogramm Agenda 21 an, das auf der Konferenz fuer Umwelt und Entwicklung 1992 in Rio de Janeiro verabschiedet wurde. Damit verstaendigte sich die internationale Staatengemeinschaft auf das 'Leitbild der nachhaltigen Entwicklung'. (orig./RHM)

Employment effects of the extended use of renewable energies

International Nuclear Information System (INIS)

Pfaffenberger, W.

1997-01-01

Any investment has a positive effect on employment: setting up an investment object involves a number of jobs. But in national economic terms, investments into renewable energies have an employment effect only if the investments are viewed within the context of the energy system as a whole. A global scenario for extending the use of renewable energies as it is outlined by the group 2010 is expected to have a positive effect on employment. Employment effects in connection with renewable energies are inferior to those associated with investments that are economical ex ante, such as many investments for enhancing energy efficiency. (orig./RHM)

Near-Net Shape Fabrication Using Low-Cost Titanium Alloy Powders

Energy Technology Data Exchange (ETDEWEB)

Dr. David M. Bowden; Dr. William H. Peter

2012-03-31

The use of titanium in commercial aircraft production has risen steadily over the last half century. The aerospace industry currently accounts for 58% of the domestic titanium market. The Kroll process, which has been used for over 50 years to produce titanium metal from its mineral form, consumes large quantities of energy. And, methods used to convert the titanium sponge output of the Kroll process into useful mill products also require significant energy resources. These traditional approaches result in product forms that are very expensive, have long lead times of up to a year or more, and require costly operations to fabricate finished parts. Given the increasing role of titanium in commercial aircraft, new titanium technologies are needed to create a more sustainable manufacturing strategy that consumes less energy, requires less material, and significantly reduces material and fabrication costs. A number of emerging processes are under development which could lead to a breakthrough in extraction technology. Several of these processes produce titanium alloy powder as a product. The availability of low-cost titanium powders may in turn enable a more efficient approach to the manufacture of titanium components using powder metallurgical processing. The objective of this project was to define energy-efficient strategies for manufacturing large-scale titanium structures using these low-cost powders as the starting material. Strategies include approaches to powder consolidation to achieve fully dense mill products, and joining technologies such as friction and laser welding to combine those mill products into near net shape (NNS) preforms for machining. The near net shape approach reduces material and machining requirements providing for improved affordability of titanium structures. Energy and cost modeling was used to define those approaches that offer the largest energy savings together with the economic benefits needed to drive implementation. Technical

Properties of solar gravity mode signals in total irradiance observations

International Nuclear Information System (INIS)

Kroll, R.J.; Chen, J.; Hill, H.A.

1988-01-01

Further evidence has been found that a significant fraction of the gravity mode power density in the total irradiance observations appears in sidebands of classified eigenfrequencies. These sidebands whose amplitudes vary from year to year are interpreted as harmonics of the rotational frequencies of the nonuniform solar surface. These findings are for non axisymmetric modes and corroborate the findings of Kroll, Hill and Chen for axisymmetric modes. It is demonstrated the the generation of the sidebands lifts the usual restriction on the parity of the eigenfunctions for modes detectable in total irradiance observations. 14 refs

Everything you might want to know about the Internet but are afraid to ask!. A new users resource

Energy Technology Data Exchange (ETDEWEB)

Thiel, E.

1993-09-01

This document is a guide to accessing the Internet and the services available on Internet. The document contains a short explanation of the Internet by E. Kroll and E. Hoffman, brief descriptions of the primary access tools, a glossary, answers to frequently asked questions about the Internet, J. Martin`s `Search for Internet Treasure` and other helpful information. The data access tools discussed in this document include Gopher, World Wide Web, WAIS, ASTRA, ARCHIE, WHOIS, NETSERV, and TRICKLE. The file transfer tool discussed is BITFTP. The two communication services discussed are NETNEWS and LISTSERV.

Variability of bio-clinical parameters in Chinese-origin Rhesus macaques infected with simian immunodeficiency virus: a nonhuman primate AIDS model.

Directory of Open Access Journals (Sweden)

Song Chen

Full Text Available BACKGROUND: Although Chinese-origin Rhesus macaques (Ch RhMs infected with simian immunodeficiency virus (SIV have been used for many years to evaluate the efficacy of AIDS vaccines and therapeutics, the bio-clinical variability of such a nonhuman primate AIDS model was so far not established. METHODOLOGY/PRINCIPAL FINDINGS: By randomizing 150 (78 male and 72 female Ch RhMs with diverse MHC class I alleles into 3 groups (50 animals per group challenged with intrarectal (i.r. SIVmac239, intravenous (i.v. SIVmac239, or i.v. SIVmac251, we evaluated variability in bio-clinical endpoints for 118 weeks. All SIV-challenged Ch RhMs became seropositive for SIV during 1-2 weeks. Plasma viral load (VL peaked at weeks 1-2 and then declined to set-point levels as from week 5. The set-point VL was 30 fold higher in SIVmac239 (i.r. or i.v.-infected than in SIVmac251 (i.v.-infected animals. This difference in plasma VL increased overtime (>100 fold as from week 68. The rates of progression to AIDS or death were more rapid in SIVmac239 (i.r. or i.v.-infected than in SIVmac251 (i.v.-infected animals. No significant difference in bio-clinical endpoints was observed in animals challenged with i.r. or i.v. SIVmac239. The variability (standard deviation in peak/set-point VL was nearly one-half lower in animals infected with SIVmac239 (i.r. or i.v. than in those infected with SIVmac251 (i.v., allowing that the same treatment-related difference can be detected with one-half fewer animals using SIVmac239 than using SIVmac251. CONCLUSION/SIGNIFICANCE: These results provide solid estimates of variability in bio-clinical endpoints needed when designing studies using the Ch RhM SIV model and contribute to the improving quality and standardization of preclinical studies.

Atmospheric and aerosol chemistry

International Nuclear Information System (INIS)

McNeill, V. Faye; Ariya, Parisa A.; McGill Univ. Montreal, QC

2014-01-01

This series presents critical reviews of the present position and future trends in modern chemical research. Short and concise reports on chemistry, each written by the world renowned experts. Still valid and useful after 5 or 10 years. More information as well as the electronic version of the whole content available at: springerlink.com. Christian George, Barbara D'Anna, Hartmut Herrmann, Christian Weller, Veronica Vaida, D. J. Donaldson, Thorsten Bartels-Rausch, Markus Ammann Emerging Areas in Atmospheric Photochemistry. Lisa Whalley, Daniel Stone, Dwayne Heard New Insights into the Tropospheric Oxidation of Isoprene: Combining Field Measurements, Laboratory Studies, Chemical Modelling and Quantum Theory. Neil M. Donahue, Allen L. Robinson, Erica R. Trump, Ilona Riipinen, Jesse H. Kroll Volatility and Aging of Atmospheric Organic Aerosol. P. A. Ariya, G. Kos, R. Mortazavi, E. D. Hudson, V. Kanthasamy, N. Eltouny, J. Sun, C. Wilde Bio-Organic Materials in the Atmosphere and Snow: Measurement and Characterization V. Faye McNeill, Neha Sareen, Allison N. Schwier Surface-Active Organics in Atmospheric Aerosols.

High-performance ceramics. Fabrication, structure, properties

International Nuclear Information System (INIS)

Petzow, G.; Tobolski, J.; Telle, R.

1996-01-01

The program ''Ceramic High-performance Materials'' pursued the objective to understand the chaining of cause and effect in the development of high-performance ceramics. This chain of problems begins with the chemical reactions for the production of powders, comprises the characterization, processing, shaping and compacting of powders, structural optimization, heat treatment, production and finishing, and leads to issues of materials testing and of a design appropriate to the material. The program ''Ceramic High-performance Materials'' has resulted in contributions to the understanding of fundamental interrelationships in terms of materials science, which are summarized in the present volume - broken down into eight special aspects. (orig./RHM)

Legal fixing of the electricity market price; Die juristische Bestimmung des Marktpreises fuer Strom

Energy Technology Data Exchange (ETDEWEB)

Lindner, Thomas

2011-07-01

The book attempts to analyze the problems of fixing electricity rates by law and to develop an approach for determining the market price for electricity. The focus is on industrial customers as this is the sector in which the market price is of practical relevance. Private customers are gone into if necessary, as is the stock market price. The main problem in determining the free market price is the very fact that it is free, i.e. in contrast to the stock market price it is not fixed and published officially. The book therefore analyzes the abstract preconditions for determining the free market price. (orig./RHM)

Sustainable prevention of resource conflicts. Approaches to minimize risk (Report 4); Rohstoffkonflikte nachhaltig vermeiden. Ansaetze zur Risikominimierung (Teilbericht 4)

Energy Technology Data Exchange (ETDEWEB)

Taenzler, Dennis; Westerkamp, Meike [Adelphi Research, Berlin (Germany); Supersberger, Nikolaus; Ritthoff, Michael; Bleischwitz, Raimund [Wuppertal Institut (Germany)

2011-04-15

Conflicting constellations and the resulting risk of conflict over raw materials are highly complex. This report investigates approaches of various groups of actors and various fields of politics to minimize this risk, with the intention of identifying and analyzing relevant and innovative approaches and to outline their potential and shortcomings in solving risky constellations. The approaches presented here were selected for their relevance and actuality. This includes, on the one hand, approaches that investigate violent conflicts in the producer countries. On the other hand, approaches are considered that attempt to influence the risk of conflict by governmental or private environmental, climate and resources policies. (orig./RHM)

Cutting with laser beams and water jets. Schneiden mit Laserstrahlung und Wasserstrahl; Anwendung, Erfahrungen, Ausblick

Energy Technology Data Exchange (ETDEWEB)

Engemann, B.K.; Herbrich, H.; Kessler, B.; Langemann, M.

1993-01-01

Cutting with laser beams and water jets left the laboratory stage about 20 years ago and has been used commercially in the last few years to an increasing extent. Both techniques offer a fast and low-cost option for producing materials and components that cannot, or only with difficulty, be worked with mechanical separation methods. The book discusses: Equipment and systems for beam generation; control systems and auxiliary systems; process fundamentals and parameters; applications. The book attempts a comprehensive review of the fields of application of both systems as well as a list of the systems now available on the market. (orig./RHM). 131 figs.

Financing of renewable electric technologies in developing countries - an Indian view

International Nuclear Information System (INIS)

Bakshi, R.

1999-01-01

To encourage the growth of renewable energy technologies and to provide adequate finance at concessional rates, the Indian Renewable Energy Development Agency Ltd. (IREDA), a Public Sector Undertaking, was established by the Ministry of Non-conventional Energy Sources in the year 1987. IREDA is perhaps the only agency of its kind established in the world for financing renewable energy projects. A number of renowned multilateral and bilateral agencies have come forward to join this global movement for sustained development, IREDA has, over the past decade of its existence, launched several innovative inititatives to promote, develop and finance various renewable energy technologies in the country. (orig./RHM)

Deutsches Atomforum. Annual report 1995

International Nuclear Information System (INIS)

Petroll, M.; Philipp, L.

1996-01-01

With its 1995 annual report, the Deutsches Atomforum renders account of its activities to its members and the public. As is demonstrated, there has been light and shadow in 1995. It is stated with satisfaction that German nuclear power stations for another year have fulfilled their task of supplying power reliably and safely. With their share of one third in public power generation, they represent an important pillar of supply. A cause for concern is that fact that a basic energy-political consensus between the major political forces on the long-term role to be played in power supply by nuclear power generation continues to be lacking. (orig./RHM) [de

Horizon Wavefunction of Generalized Uncertainty Principle Black Holes

Directory of Open Access Journals (Sweden)

Luciano Manfredi

2016-01-01

Full Text Available We study the Horizon Wavefunction (HWF description of a Generalized Uncertainty Principle inspired metric that admits sub-Planckian black holes, where the black hole mass m is replaced by M=m1+β/2MPl2/m2. Considering the case of a wave-packet shaped by a Gaussian distribution, we compute the HWF and the probability PBH that the source is a (quantum black hole, that is, that it lies within its horizon radius. The case β0, where a minimum in PBH is encountered, thus meaning that every particle has some probability of decaying to a black hole. Furthermore, for sufficiently large β we find that every particle is a quantum black hole, in agreement with the intuitive effect of increasing β, which creates larger M and RH terms. This is likely due to a “dimensional reduction” feature of the model, where the black hole characteristics for sub-Planckian black holes mimic those in (1+1 dimensions and the horizon size grows as RH~M-1.

Scattering of Non-Relativistic Charged Particles by Electromagnetic Radiation

Science.gov (United States)

Apostol, M.

2017-11-01

The cross-section is computed for non-relativistic charged particles (like electrons and ions) scattered by electromagnetic radiation confined to a finite region (like the focal region of optical laser beams). The cross-section exhibits maxima at scattering angles given by the energy and momentum conservation in multi-photon absorption or emission processes. For convenience, a potential scattering is included and a comparison is made with the well-known Kroll-Watson scattering formula. The scattering process addressed in this paper is distinct from the process dealt with in previous studies, where the scattering is immersed in the radiation field.

An infinite-order two-component relativistic Hamiltonian by a simple one-step transformation.

Science.gov (United States)

Ilias, Miroslav; Saue, Trond

2007-02-14

The authors report the implementation of a simple one-step method for obtaining an infinite-order two-component (IOTC) relativistic Hamiltonian using matrix algebra. They apply the IOTC Hamiltonian to calculations of excitation and ionization energies as well as electric and magnetic properties of the radon atom. The results are compared to corresponding calculations using identical basis sets and based on the four-component Dirac-Coulomb Hamiltonian as well as Douglas-Kroll-Hess and zeroth-order regular approximation Hamiltonians, all implemented in the DIRAC program package, thus allowing a comprehensive comparison of relativistic Hamiltonians within the finite basis approximation.

Promotion of direct marketing and supply on demand of electric power from renewable energy sources. Final report; Foerderung der Direktvermarktung und der bedarfsgerechten Einspeisung von Strom aus Erneuerbaren Energien. Endbericht

Energy Technology Data Exchange (ETDEWEB)

NONE

2010-06-23

The study investigates the promotion of direct marketing and supply on demand of electric power from renewable energy sources in Germany. the study shows that renewable energy sources are a good option for facing the challenges of the future. However, the potential is often left unused because of a lack of incentives in the current pricing system. To solve this problem, the Federal Ministry of the Environment, Nature Conservation and Nuclear Safety authorized two studies that are to enable or improve the utilization of the integration potentials of the renewable energy sources. Two model proposals based on these studies are presented here. The model proposing a bonus for combined-cycle power plants is to ensure supply on demand of electric power from renewables with the aid of integrated power storage systems. However, it is found that this model will not generate significant effects for power supply on demand. The second model proposes financial incentives; it will work well for renewable power supply systems that can be controlled, e.g. bioenergy, run-of-river power plants with power storage, and biogas plants. On the other hand, supply-dependent technologies like wind power, photovoltaic power, run-of-river power plants without power storage, and geothermal power plants with very low variable cost, the goal is not fully reached. In contrast to the first model, the market incentives model will enhance the integration of renewable energy sources in the competitive market by largely eliminating market risks. (orig./RHM)

Delphi report 1995 on developments in science and technology. Mini Delphi; Delphi-Bericht 1995 zur Entwicklung von Wissenschaft und Technik. Mini-Delphi

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-03-01

In August 1993 the first German `Delphi Report on Developments in Science and Technology` was published. It was elaborated by the Fraunhofer Institute for System Engineering and Innovation Research (FhG-ISI) in cooperation with the Japanese National Institute of Science and Technology Policy (NISTEP). The `MINI-DELPHI` now completed by FhG-ISI, again in cooperation with NISTEP, is a further development of the Delphi approach in that it is more differentiated in its questions and assessment criteria than its predecessors. `MINI-DELPHI` is not intended as a comprehensive forecast on technology in general but rather focusses on key topics. Its emphasis is on technology demand and the relevance of technologies to social issues. Although the Mini-Delphi study was primarily aimed at further refining the methodology employed, it nevertheless contains a wealth of information and details on circumscript questions. The requisite database is provided by tables on the results of two inquiry rounds among Japanese and German experts. (orig./RHM) [Deutsch] Im August 1993 wurde der erste deutsche `Delphi-Bericht zur Entwicklung von Wissenschaft und Technik` veroeffentlicht. Er war vom Fraunhofer-Institut fuer Systemtechnik und Innovationsforschung (FhG-ISI) in Zusammenarbeit mit dem japanischen National Institute of Science and Technology Policy (NISTEP) erarbeitet worden. Mit dem jetzt vorliegenden `MINI-DELPHI` hat das FhG-ISI - wieder in Zusammenarbeit mit dem NISTEP - den Delphi-Ansatz fortentwickelt und sowohl hinsichtlich der Fragen als auch der Beurteilungskriterien weiter ausdifferenziert. `MINI-DELPHI` bezweckt keine umfassende Technologievorausschau, sondern konzentriert sich auf Schluesselthemen. Im Vordergrund steht der Gedanke des Technikbedarfs und die Relevanz fuer gesellschaftliche Fragestellungen. Obwohl die Mini-Delphi-Studie vorrangig der Weiterentwicklung der Methodik dient, enthaelt sich eine Fuelle von Informationen und Details zu Einzelfragen. Die im Bericht

Managing the heritage of east-German uranium mining and uranium processing

International Nuclear Information System (INIS)

Hagen, M.

1997-01-01

The corporate aim of the WISMUT GmbH, in accordance with the current statutory regulations of the Federal Republic of Germany, is the decommissioning of its installations as well as the reclamation and revegetation of a landscape and an environment on which decades of uninhibited extraction and processing of uranium ore have left their imprint. Expenditure for this major ecological project of international scale is put at 13 billion marks. These funds are provided by the Federal government in the course of an envisaged period of 10 to 15 years. They enable WISMUT to buy the best know-how to be obtained in Germany and abroad for the decommissioning and reclamation works. (orig./RHM) [de

Financing renewable energies through MicroCredit

Energy Technology Data Exchange (ETDEWEB)

Wimmer, N. [Terra One World Network, Vaterstetten (Germany)

1999-07-01

The environment, which led to the creation of the Grameen Bank was: no access to credit for the poor in rural Bangladesh. The environment, which led to the creation of Grameen Shakti was: no access to electricity and renewable energies. Through the experience of Grameen, we see the poor differently: they are good business partners, open to modern technology, they can and must be integrated into the economy. Microcredit not only creates purchasing. Power, but acceptance of new ideas and technologies. Microcredit is a catalyst for change. Our challenge is to create an environment which allows change to take place. To create an environment which finances sustainable development. Sustainable development is everybody's business. (orig./RHM)

Asia's hunger for energy. Raw materials exploitation taken to the limit; Asiens Energiehunger. Rohstoffe am Limit

Energy Technology Data Exchange (ETDEWEB)

Pilny, Karl; Reid, Gerard

2011-07-01

The world is facing a dramatic change, owing to the rapid economic growth of China and India, which is unique in history. The result will be an enraged battle for limited fossil fuels like oil and gas. To secure energy resources, the current and future powers will increasingly use power play and also armed solutions. This is why we need profound changes, not only in the manner of power generation but also in the distribution and uses of the generated power. The book intends to give the reader profound understanding of the role of raw materials in future energy supply and of the options we have to solve the energy problem. (orig./RHM)

Financing renewable energies through MicroCredit

International Nuclear Information System (INIS)

Wimmer, N.

1999-01-01

The environment, which led to the creation of the Grameen Bank was: no access to credit for the poor in rural Bangladesh. The environment, which led to the creation of Grameen Shakti was: no access to electricity and renewable energies. Through the experience of Grameen, we see the poor differently: they are good business partners, open to modern technology, they can and must be integrated into the economy. Microcredit not only creates purchasing. Power, but acceptance of new ideas and technologies. Microcredit is a catalyst for change. Our challenge is to create an environment which allows change to take place. To create an environment which finances sustainable development. Sustainable development is everybody's business. (orig./RHM)

Comparison of selected approaches to finance renewable energy projects in European countries

International Nuclear Information System (INIS)

Langniss, O.

1999-01-01

A large number of proven technical solutions exists for the use of renewable energies. However, their dissemination is still too slow to meet the political goal of substituting for 8-15% of the primary energy demand in the European Union by the year 2010. Even renewable energy systems (RES) with an economic potential are only partly exploited. The FIRE research project financed partly in the JOULE program analyses and compares the means of financing RES in Austria, Denmark, Germany, the Netherlands, Spain, Sweden and the United Kingdom to put forward best practice recommendations so that renewable energy depolyments will occur at a faster rate. FIRE addresses to politicians, to potential investors and to project-developers. (orig./RHM)

Confinement of light in periodic structures with negative phase velocity

International Nuclear Information System (INIS)

Driss Bria; Abdelmajid Essadqui; Bahram Djafari-Rouhani; Mohamed Azizi; Abdellah Daoudi; Abdelkrim Nougaoui

2008-08-01

We discuss unusual features of wave propagation in periodic arrays of slabs made of transparent left-handed metamaterials with simultaneously negative dielectric permittivity and magnetic permeability, and demonstrate the possibility of light confinement due to the appearance of complete photonic band-gaps in such one-dimensional structures. With an appropriate choice of the parameters, we show that it is possible to realize an absolute (or omnidirectional) band gap for either transverse electric (TE) or transverse magnetic (TM) polarizations of the electromagnetic waves. A combination of two multilayer structures composed of right-handed material (RHM) and left-handed metamaterials LHM is proposed to realize, in a certain range of frequency, an omnidirectional reflector of light for both polarizations. (author)

Customer acceptance of renewable energy sources. Target group segmentation by means of a lifestyle typology of end users; Verbraucherakzeptanz von Erneuerbaren Energien. Zielgruppensegmentierung durch Einordnung privater Endverbraucher in eine Lebensstiltypologie

Energy Technology Data Exchange (ETDEWEB)

Wiedmann, Klaus-Peter; Zitzewitz, Mareike von

2010-07-01

Sustainable use of resources worldwide, protection of the global climate, and enhanced energy efficiency are important challenges for Germany in the 21st century. A key element is the energy turnaround by enhanced use of renewable energy sources, especially in the private sector. The publication presents an acceptance model relating to this context; it is based on the three-component attitude theory and supplemented by concrete, behaviour-related acceptance of use. Statistical methods of verification showed that acceptance in attitude is the necessary condition for acceptance of action, which in turn is the necessary condition for acceptance of use. This means that acceptance in attitude will be the most common type of acceptance and acceptance of use the least common one. On the basis of the acceptance model and of other active and passive variables, a two-stage market segmentation and a cluster analysis were carried out in order to identify four different lifestyle types that are target groups for renewable energy sources. Among the active variables of the private end consumers were personality characteristics, personal values, technology affinity, thriftiness, environmental awareness and environmental behaviour. Descriptive or passive variables were recreational activities, media consumption, orientation in style and taste, and demographic characteristics. (orig./RHM)

Wanted: entrepreneurs in occupational therapy.

Science.gov (United States)

Anderson, Kristin M; Nelson, David L

2011-01-01

The American Occupational Therapy Association (AOTA) has challenged occupational therapy practitioners to advance the profession so that we may become more "powerful" and "widely recognized" by the year 2017 (AOTA, 2007a). To fully achieve this vision, this article argues that the profession should encourage occupational therapy entrepreneurship. As Herz, Bondoc, Richmond, Richman, and Kroll (2005, p.2) stated, "Entrepreneurship may provide us with the means to achieve the outcomes we need to succeed in the current health care environment." This article also argues the urgency of seizing the many opportunities that entrepreneurship offers and recommends specific actions to be taken by AOTA and by therapists.

Atmospheric and aerosol chemistry

Energy Technology Data Exchange (ETDEWEB)

McNeill, V. Faye [Columbia Univ., New York, NY (United States). Dept. of Chemical Engineering; Ariya, Parisa A. (ed.) [McGill Univ. Montreal, QC (Canada). Dept. of Chemistry; McGill Univ. Montreal, QC (Canada). Dept. of Atmospheric and Oceanic Sciences

2014-09-01

This series presents critical reviews of the present position and future trends in modern chemical research. Short and concise reports on chemistry, each written by the world renowned experts. Still valid and useful after 5 or 10 years. More information as well as the electronic version of the whole content available at: springerlink.com. Christian George, Barbara D'Anna, Hartmut Herrmann, Christian Weller, Veronica Vaida, D. J. Donaldson, Thorsten Bartels-Rausch, Markus Ammann Emerging Areas in Atmospheric Photochemistry. Lisa Whalley, Daniel Stone, Dwayne Heard New Insights into the Tropospheric Oxidation of Isoprene: Combining Field Measurements, Laboratory Studies, Chemical Modelling and Quantum Theory. Neil M. Donahue, Allen L. Robinson, Erica R. Trump, Ilona Riipinen, Jesse H. Kroll Volatility and Aging of Atmospheric Organic Aerosol. P. A. Ariya, G. Kos, R. Mortazavi, E. D. Hudson, V. Kanthasamy, N. Eltouny, J. Sun, C. Wilde Bio-Organic Materials in the Atmosphere and Snow: Measurement and Characterization V. Faye McNeill, Neha Sareen, Allison N. Schwier Surface-Active Organics in Atmospheric Aerosols.

Cross section for the 103Rh(n,n')103Rhm reaction in the energy range 5.7 endash 12 MeV

International Nuclear Information System (INIS)

Miah, M.M.; Strohmaier, B.; Vonach, H.; Mannhart, W.; Schmidt, D.

1996-01-01

The 103 Rh(n,n ' ) 103 Rh m cross section was measured by the activation method in the neutron energy range 5.7 endash 12 MeV with an uncertainty of ≅5%. Monoenergetic neutrons produced by the D(d,n) 3 He reaction were used to irradiate metallic Rh samples at 0 degree relative to the deuteron beam. The K x rays from 103 Rh m were measured with a calibrated Si detector, and the neutron fluence was determined by means of a 238 U fission chamber. The measured cross sections resolve the discrepancies in previous data and agree with the results of recent statistical model calculations of the fast-neutron cross sections of rhodium. copyright 1996 The American Physical Society

Investigations of mode I crack propagation in fibre-reinforced plastics with real time X-ray tests and simultaneous sound emission analysis

International Nuclear Information System (INIS)

Brunner, A.; Nordstrom, R.; Flueeler, P.

1992-01-01

The described investigation of crack formation and crack propagation in mode I (tensile stress) in fibre-reinforced plastic samples, especially uni-directional carbon fibre reinforced polyether-ether ketone (PEEK) has several aims. On the one hand, the phenomena of crack formation and crack propagation in these materials are to be studied, and on the other hand, the draft standards for these tests are to be checked. It was found that the combination of real time X-ray tests and simultaneous sound emission analysis is excellently suited for the basic examination of crack formation and crack propagation in DCB samples. With the aid of picture processing and analysis of the video representation, consistent crack lengths and resulting G IC values can be determined. (orig./RHM) [de

Betatron tomography with the use of non-linear backprojection techniques

International Nuclear Information System (INIS)

Baranov, V.A.; Temnik, A.K.; Chakhlov, V.L.; Chekalin, A.S.

1995-01-01

The testing of heavy components under non-steady-state condition (at erection and building sites, at jigs, for testing of welded joints and valving of oil and gas pipelines, power and boiler plants repair, building construction and for testing of castings and welded joints of large thickness) traditionally belongs to most pressing NDT problems. One of essential prerequisites for success at this point was the elaboration of appropriate high energy radiation sources, in particular small size pulse betatrons like MIB-4 and MIB-6 with the energy 4 and 6 MeV. Now, taking into account the new possibilities of tomography, the adaptation of fresh methods of cross-sectional visualisation (like non-linear tomosynthesis) to this conventional problem-solving area is of special interest. (orig./RHM)

Ductile zirconium powder by hydride-dehydride process

Energy Technology Data Exchange (ETDEWEB)

Krishnan, T S [BHABHA ATOMIC RESEARCH CENTRE, BOMBAY (INDIA); CHAUDHARY, S [NUCLEAR FUEL COMPLEX, HYDERABAD (INDIA)

1976-09-01

The preparation of ductile zirconium powder by the hydride-dehydride process has been described. In this process massive zirconium obtained from Kroll reduction of ZrCl/sub 4/ is first rendered brittle by hydrogenation and the hydride crushed and ground in a ball mill to the required particle size. Hydrogen is then hot vacuum extracted to yield the metal powder. The process has been successfully employed for the production of zirconium powders with low oxygen content and having hardness values in the range of 115-130 BHN, starting from a zirconium sponge of 100-120 BHN hardness. Influence of surface characteristics of the starting metal on its hydriding behaviour has been studied and the optimum hydriding-dehydriding conditions established.

Romanistik und gender studies

Directory of Open Access Journals (Sweden)

Susanne Schlünder

2000-11-01

Full Text Available Die beiden Bände bieten ein breites Spektrum von Beiträgen zur französischen, italienischen und spanischen Literaturwissenschaft. Gedankliche Grundlage der im einzelnen unterschiedlichen Ansätze und Zielsetzungen ist ein im Anschluß an Judith Butler gender-reflektierendes, diskursives Konzept von Geschlecht, dessen wissenschaftsgeschichtliche Herleitung und Perspektiven Renate Kroll einleitend darlegt. Die einzelnen Artikel beschäftigen sich zum einen mit literarischen Strategien, die Schriftstellerinnen vom Mittelalter bis zur Gegenwart erprobt haben, und hinterfragen dabei die Rolle weiblicher Autoren in Literaturgeschichte und Literaturgeschichtsschreibung. Zum anderen widmen sie sich den literarischen Inszenierungs- und Repräsentationsformen von Weiblichkeit und stellen darüber einen Bezug zur Lebenswelt der behandelten Autorinnen her.

Static electric polarizabilities and first hyperpolarizabilities of molecular ions RgH + (Rg = He, Ne, Ar, Kr, Xe): ab initio study

Science.gov (United States)

Cukras, Janusz; Antušek, Andrej; Holka, Filip; Sadlej, Joanna

2009-06-01

Extensive ab initio calculations of static electric properties of molecular ions of general formula RgH + (Rg = He, Ne, Ar, Kr, Xe) involving the finite field method and coupled cluster CCSD(T) approach have been done. The relativistic effects were taken into account by Douglas-Kroll-Hess approximation. The numerical stability and reliability of calculated values have been tested using the systematic sequence of Dunning's cc-pVXZ-DK and ANO-RCC-VQZP basis sets. The influence of ZPE and pure vibrational contribution has been discussed. The component αzz has increasing trend in RgH + while the relativistic effect on αzz leads to a small increase of this molecular parameter.

A global energy juncture between 2020 and 2030. Causes and consequences for consumers, governments, and the petroleum industry; Zwischen 2020 und 2030 werden fuer den globalen Energiemix die Weichen neu gestellt. Die Gruende und Konsequenzen fuer Verbraucher, Regierungen und die Mineraloelindustrie

Energy Technology Data Exchange (ETDEWEB)

Schollnberger, Wolfgang E.

2013-01-15

Today, lighting, heat, mobility and electric power are provided on the basis of petroleum, natural gas, and coal. This raises the question of the future energy situation. A diagram first published in 2006 and showing the development of the energy sector from 1945 through 2100 predicts a major change in the energy mix for the period between 2020 and 2030. While the growth rates of fossil energy sources will slow down, new forms of energy will become more important. Forecasts of consumption and supply suggest that mankind may master this critical juncture step by step as long as this will take place between 2020 and 2030. Any delay may cause political and economic problems on a global scale and at all levels, from government level to local, and should therefore be avoided. (orig./RHM)

Middle East, Russia and Caspian region - new geopolitics for oil and gas flows in the Eastern hemisphere

International Nuclear Information System (INIS)

Konoplyanik, A.

1998-01-01

The Caspian Oil Basin and its would-be impact on the world energy sales has been a big talking issue of late. The Caspian Rim states will join the international oil/gas market simultaneously with new Oil Industry projects coming on-stream in Russia. Both Russia and Caspian states will influence the existing oil/gas flows and balance of forces on the oil/gas markets of the Eastern Hemisphere. What will be the resultant of these two vectors? Will a stronger stand of Russia as one of the existing world market participants and a new big rival - the Caspian states, exert a profound influence on the competitive rating of the Middle East countries as oil/gas exporting majors? Let us try to answer the questions within this contribution. (orig./RHM)

Renewable energy sources in Germany, 1990 through 2007; Erneuerbare Energien in Deutschland 1990 bis 2007

Energy Technology Data Exchange (ETDEWEB)

Boehme, Dieter; Duerrschmidt, Wolfhart (comps.)

2009-11-15

This brochure presents a picture of the rapid development of renewable energy sources in the years between 1990 and 2007. It shows the rapid growth and informs on the importance of renewable energy sources for climate protection. The new CDU/FDP government headed by Angela Merkel stressed its intention to develop the potential of renewable energy sources. Apart from the effect of higher energy efficiency, this will also help Germany to make an ambitious contribution to climate protection world-wide. Renewable energy sources are to provide the biggest share of power supply in the future. By 2020, the EEG (German Renewables Act) envisages at least a 30 percent share for renewable energy sources as an intermediate goal. In the field of heat supply, at least 14 percent are envisaged fro 2020. (orig./RHM)

Not the market allowing to quickly pocket money. Siemens/KWU and their commitments in Central and Eastern Europe; ``Kein Markt fuer schnelles Geld``. Das Engagement von Siemens/KWU in Mittel- und Osteuropa

Energy Technology Data Exchange (ETDEWEB)

Schwegmann, P.

1997-05-01

After the break-up of the Eastern Bloc, Siemens very soon concluded strategic alliances with the big and most qualified Russian power plant manufacturers, busy activities currently focusing on the nuclear sector with retrofitting and safety engineering work in a number of NPPs. Points of main interest are systems analysis, recurrent inspection of primary loop components, and the installation of diagnostic systems for operational monitoring, as well as the instrumentation and control systems. (Orig./RHM) [Deutsch] In Russland ist es Siemens nach der politischen Wende gelungen, mit den groessten und qualifiziertesten Kraftwerksherstellern Russlands strategisch bedeutsame Allianzen einzugehen. Sehr ruehrig ist man auf dem Nuklear-Sektor. So werden gegenwaertig die Sicherheitseinrichtungen einer Reihe von Kernkraftwerken nachgebessert. Schwerpunkte sind dabei Analysen, wiederkehrende Pruefungen an Komponenten der Primaerkreislaeufe sowie die Installation von Diagnosesystemen, Betriebs- und Leittechnik. (orig.)

Energy contracting. Energy-related services and decentral energy supply. 2. ed.; Energie-Contracting. Energiedienstleistungen und dezentrale Energieversorgung

Energy Technology Data Exchange (ETDEWEB)

Hack, Martin

2012-11-01

According to the author, the intended German energy turnaround cannot be achieved solely on the basis of power from renewables and by constructing new passive buildings. Also required are decentral energy services if the energy saving and efficiency goals are to be achieved. In spite of many variations, the basic structure of these is the following: A contractor providing energy services does not only supply energy but also carries the risk and responsibility for efficient supply. This will relieve energy users, whether industrial or trade enterprises, public administration or home owners from this task; also, this integrated approach will open up undeveloped efficiency potentials. The book discusses current legal issues in a clear and practice-oriented manner and also provides a check list for energy contracting and an exemplary contract. (orig./RHM)

Evaluation of corrosion behaviour of tantalum coating obtained by low pressure chemical vapor deposition using electrochemical polarization

Science.gov (United States)

Levesque, A.; Bouteville, A.; de Baynast, H.; Laveissière, B.

2002-06-01

antalum coatings are elaborated on titanium substrates through Low Pressure Chemical Vapor Deposition from tantalum pentachloride-hydrogen gaseous phase at a deposition temperature of 800 °C and a total pressure of 3.3 mbar. The aim of this paper is to evaluate the effectiveness of this tantalum coating in corrosive solution. Optical Microscopy and Scanning Electron Microscopy observations reveal that deposits are of 1.7 μm in thickness and conformal. The corrosion resistance of tantalum coated titanium substrates is quantified through standard potentiodynamic polarization method. Even for tantalum coatings exhibiting some defects as pores, the corrosion current density is as low as 0.25 mA/cm^2.in very agressive solutions like kroll reagent (HN03/HF).

Local unitary transformation method for large-scale two-component relativistic calculations: case for a one-electron Dirac Hamiltonian.

Science.gov (United States)

Seino, Junji; Nakai, Hiromi

2012-06-28

An accurate and efficient scheme for two-component relativistic calculations at the spin-free infinite-order Douglas-Kroll-Hess (IODKH) level is presented. The present scheme, termed local unitary transformation (LUT), is based on the locality of the relativistic effect. Numerical assessments of the LUT scheme were performed in diatomic molecules such as HX and X(2) (X = F, Cl, Br, I, and At) and hydrogen halide clusters, (HX)(n) (X = F, Cl, Br, and I). Total energies obtained by the LUT method agree well with conventional IODKH results. The computational costs of the LUT method are drastically lower than those of conventional methods since in the former there is linear-scaling with respect to the system size and a small prefactor.

Reuse of spent fuel cladding Zr by molten salt toward advanced recycle society

International Nuclear Information System (INIS)

Amano, Osamu; Kobayashi, Hiroaki; Suzuki, Kazunori; Yasuike, Y.; Sato, Nobuaki

2003-01-01

Cladding tubes of zircaloy 95% generated from reprocessing process for spent nuclear fuels are to be chopped in about 3 cm length, compacted and solidified with cements. This paper reports the summary of investigation of the present possible techniques for zirconium recovery: (1) electrolysis of molten salts (Zr-chlorides and/or fluorides) and (2) separation as volatile zirconium chlorides (ZrCl 4 ) (chloride volatility process) followed by reaction with metallic magnesium at 900degC to produce sponged Zr (Kroll method). The feasibility are discussed from the point of view of reduction of secondary radioactive wastes, accumulation of such nuclides as Co-60 and Ni-63 in electrolytic basin, radioactivity estimation in the products, and also problems of cleaning and reducing chemicals. (S. Ohno)

A sudden brightness decrease of the young pre-MS object GM Cep

Science.gov (United States)

Munari, U.; Castellani, F.; Giannini, T.; Antoniucci, S.; Lorenzetti, D.

2017-11-01

In the framework of our EXor monitoring programme dubbed EXORCISM (EXOR OptiCal and Infrared Systematic Monitoring - Antoniucci et al. 2013 PPVI, Lorenzetti et al. 2007 ApJ 665, 1182; Lorenzetti et al. 2009 ApJ 693, 1056), we observed a new fading of the optical brightness of the Young Stellar Object (YSO) GM Cep (d=870 pc). This is a well studied variable (Semkov & Peneva 2012 APSS,338,95; Ibryamov et al. 2015 PASA,32,11; Xiao, Kroll, & Henden 2010 AJ, 139, 1527; Sicilia-Aguilar et al. 2008 ApJ,673,382-3) whose light-curve is dominated by recurrent brightness dims, interpreted as non-periodical eclipse events due to orbiting dust structures that move along the line of sight (UXor-type variability - Grinin 1988).

Photovoltaic energy conversion and wind power plants creating new jobs; Arbeitsplaetze durch Photovoltaik und Windenergie

Energy Technology Data Exchange (ETDEWEB)

Hille, G.; Hoffmann, V.U. [Fraunhofer ISE, Freiburg (Germany); Dienhart, H.; Langniss, O.; Nitsch, J. [DLR, Stuttgart (Germany)

1997-12-01

Experts are unanimous that opening up new markets through innovative technologies will be the successful strategy for reversing the upward trend of unemployment in Germany. This approach puts renewable energy sources into the foreground, as enhanced use of wind power and photovoltaic energy conversion will no doubt create new jobs. These technologies will, however, require favourable regulatory framework conditions in order to become a significant force in combatting unemployment. (orig./CB) [Deutsch] Es gilt unter Experten als sicher, dass eine Umkehr am Arbeitsmarkt nur dadurch zu schaffen ist, dass innovative Technologien genutzt und damit neue Maerkte erschlossen werden. Demnach koennte etwa dem Ausbau der regenerativen Energietraeger Wind und Photovoltaik zur Schaffung zukunftssicherer Arbeitsplaetze eine grosse Bedeutung zukommen. Einen ernstzunehmenden Beitrag im Kampf gegen die Arbeitslosigkeit koennen diese Technologien allerdings nur unter bestimmten Rahmenbedingungen leisten. (orig./RHM)

XANES and XMCD studies of FeRh and CoRh nanoparticles

Energy Technology Data Exchange (ETDEWEB)

Smekhova, A; Wilhelm, F; Rogalev, A [European Synchrotron Radiation Facility, Grenoble Cedex 9, 38043 (France); Atamena, N; Ciuculescu, D; Amiens, C [Laboratoire de Chimie de Coordination, UPR 8241-CNRS, Toulouse Cedex 04, 31077 (France); Lecante, P, E-mail: smeal@esrf.f [Centre d' Elaboration de Materiaux et d' Etudes Structurales, UPR 8011-CNRS, Toulouse Cedex 04, 31055 (France)

2010-01-01

Element-selective magnetic properties of new core-shell bimetallic MRh (M=Fe or Co) nanoparticles (NP{sub S}) of 50/50 composition with either M-Rh or Rh-M core/shell order and an average diameter of {approx}2 nm have been investigated by X-ray Absorption Spectroscopy (XANES) and X-Ray Magnetic Circular Dichroism (XMCD) technique. XANES spectra at the Rh L{sub 2,3} edges exhibit the same characteristic features for all systems having the Rh metal enriched shell. XMCD experiments at the same edges have shown that 4d states of Rh atoms acquire a magnetic moment as a result of hybridization with iron or cobalt 3d states. As expected the value of this induced moment depends on the 3d transition metal and on the core/shell chemical order in the nanoparticle.

Rilem TC 203-RHM: Repair mortars for historic masonry. Requirements for repointing mortars for historic masonry

NARCIS (Netherlands)

Hees, R.P.J. van; Groot, C.; Hughes, J.J.; Balen, K. van; Bicer-Simsir, B.; Binda, L.; Elsen, J.; Konow, T. von; Lindqvist, J.E.; Papayanni, I.; Subercaseaux, M.; Tedeschi, C.; Toumbakari, E.E.; Thompson, B.

2012-01-01

This paper gives a summary of functional and performance requirements for repointing mortars for historic masonry (design, execution and maintenance). Successful performance of repair and conservation of mortar in historic masonry requires more care with design and execution than with modern

Learning from history: A case study in nuclear fuel

International Nuclear Information System (INIS)

Robertson, J.A.L.

1996-01-01

The award of the 1993 W.J. Kroll Zirconium Medal recognized the value of cooperative, multidisciplinary, applied research in tackling practical problems. This paper suggests that several other lessons relevant to the current debate on science-and-technology (S and T) policy can be drawn from experience a quarter of a century ago. It outlines how close cooperation among those involved with the fuel for the Canadian CANDU heavy-water reactors identified a problem, then proceeded to solve it expeditiously. This capability for a rapid response to an unforeseen problem was no accident, but arose out of the conditions that existed at the Chalk River Laboratory of Atomic Energy of Canada Limited (AECL) and a deliberate policy to maintain this capability even when the utility's power reactors were demonstrating excellent performance

Extractive metallurgy of zirconium--1945 to the present

International Nuclear Information System (INIS)

Franklin, D.G.; Adamson, R.B.

1984-01-01

Although the history of the reduction of zirconium dates from 1824 and the first ductile zirconium metal was produced in the laboratory in 1914, modern reduction practice was pioneered by the U.S. Bureau of Mines starting in 1945. This paper reviews the history of the extractive metallurgy of zirconium from the early work of W. J. Kroll and co-workers at the Bureau of Mines in Albany, Ore., through the commercial development of the production of reactor-grade zirconium metal which was spurred by the requirements of the Naval Reactor Program and the development of commercial nuclear power. Technical subjects covered include processes for opening the ore, zirconium-hafnium separation, chlorination of zirconium oxide, reduction processes, and electrowinning of zirconium metal. Proposed new processes and process modifications are reviewed

Harmonization of power pricing in accordance with section 1, subsection 1 and section 12, subection 2 of the Bundestarifordnung Elektrizitaet (BTO Elt 1990) and the current market value of a power transmission line system as takeover price on the expiry of franchise agreements; Harmonisierung der Strompreisbildung gemaess Para. 1 Abs. 1 und Para. 12 Abs. 2 BTO Elt 1990 und dem Sachzeitwert als Uebernahmeentgelt bei Beendigung von Stromkonzessionsvertraegen

Energy Technology Data Exchange (ETDEWEB)

Schumacher, K.S.

1996-12-01

From the interplay of the energy-economic regulatory framework it follows that no drawbacks must arise from a change of ownership for either the utility that sells part of its transmission line system or the power customers. In the procedure commonly adopted in energy-economic practice for assessing the current market value of power mains, assessment errors having a contrary effect are tolerated in establishing the takeover price in order to reach a consensus. In this way, if profit losses have occurred in the past due to power pricing with excessive and premature reimbursements to customers for grants received towards construction costs (these reimbursements being mandatory under the code of financial practice but implicitly faulty), these losses are compensated for in the net sales price. As a consequence, however, future power prices need to be higher if they are to cover costs. As is demonstrated in the paper, the current market value, which is defined as Sieben`s material asset value, takes into account past costs that were not covered by profits from power sales. In other words, the utility that sells its power mains at a price corresponding to the current market value does not incur an implicit loss or gain, nor does the change in ownership of the power mains involve charges to customers. (orig./RHM) [Deutsch] Aus dem Zusammenspiel der energiewirtschaftlichen Rahmenordnung folgt insgesamt, dass der Versorgerwechsel weder zum Nachteil fuer das abgebende EVU noch zum Nachteilen fuer die Abnehmer/Verbraucher fuehren darf. Das in der energiewirtschaftlichen Praxis uebliche Verfahren der Sachzeitwertermittlung nimmt zum Erreichen eines Konsenses bezueglich des Uebergabepreises entgegengerichtete Bewertungsfehler in Kauf. Damit sucht man Erloeseinbussen der Vergangenheit durch eine von der Arbeitsanleitung veranlasste kalkulatorsich fehlerhafte Strompreisbildung mit zu hohen fruehzeitigen BKZ-Rueckverguetungen an die Kunden im Netzverkaufsentgelt zu kompensieren

The pricing relevance of insider information; Die Preiserheblichkeit von Insiderinformationen

Energy Technology Data Exchange (ETDEWEB)

Kruse, Dominik

2011-07-01

The publication attempts to describe the so far discussion concerning the feature of pricing relevance and to develop it further with the aid of new research approaches. First, a theoretical outline is presented of the elementary regulation problem of insider trading, its historical development, and the regulation goals of the WpHG. This is followed by an analysis of the concrete specifications of the law. In view of the exemplarity of US law, a country with long experience in regulation of the capital market, the materiality doctrine of US insider law is gone into in some detail. The goals and development of the doctrine are reviewed in the light of court rulings. The third part outlines the requirements of German law in order to forecast the pricing relevance of insider information, while the final part presents a critical review of the current regulations on pricing relevance. (orig./RHM)

Energy policy. Technical developments, political strategies, and concepts of action regarding renewable energy sources and rational energy use

International Nuclear Information System (INIS)

Brauch, H.G.

1997-01-01

This interdisciplinary study book deals with problems from the history of energy, energy sytems, energy engineering, and the potential of renewable energy sources: hydro and wind power, biomass, geothermal energy, photovoltaics and solar thermal conversion; the improvement of boundary conditions for their transfer to market; concepts of action and project funding preferences of the EU, USA and Japan in this sector; relevant activities of the federal German government and proposals by non-governmental players in the field as well as strategies for rational energy use; methods for building an energy consensus and criteria for valuating energy systems; concepts of action and proposals for extending solar energy use in the Mediterranean and Afrika, as well as political factors governing the market introduction and export promotion of renewable energy technologies in this triad: the USA, Japan, and the European Union. Seven of the papers contained in the book are individually recorded. (orig./RHM). 76 figs., 100 tabs [de

Propagation Properties of Airy Beam through Periodic Slab System with Negative Index Materials

Directory of Open Access Journals (Sweden)

Long Jin

2018-01-01

Full Text Available Based on light transfer matrix and electric field vector equation, the evolution of Airy beam propagating in periodic slab system with three negative index materials (NIMs and its transmission mechanism are investigated. The intensity profiles on emergent surface of periodic slab system and side view of Airy beam propagating in each right handed material (RHM and double negative material (DNM unit including lossless and losses DNMs are discussed. It is revealed that the self-recovery Airy beam can be achieved in long distance by using lossless periodic slab system as long as the negative refractive index nl=-nr and each unit length L=Z. As to losses slab system contained DNMs, the smaller the collision frequencies are, the better the Airy beam quality is formed. It is expected that the proposed manner of beam transmission and corresponding conclusions can be useful for extension applications of optical control, especially for optical communication and optical encryption technique.

Cogeneration systems in district heating. Dimensioning and economic efficiency; BHKW in der Nahwaermeversorgung. Dimensionierung und Wirtschaftlichkeit

Energy Technology Data Exchange (ETDEWEB)

Stadtmueller, H. [Isar-Amperwerke AG, Muenchen (Germany)

1999-07-01

Even operators of industrial-scale power stations have good reasons to look into combined heat and power generation. CHP systems have a high thermal and electric efficiency, especially in case of optimized integration into the existing power station park of a public utility. Utilities can supply heat as well as electricity and thus improve customer loyalty by full-scale coverage of a locally limited market. The author presents activities for gaining strategic advances in the (niche) market for combined heat and power generation systems. [German] Auch fuer ein EVU, das Grosskraftwerke betreibt, gibt es gute Gruende sich mit BHKW zu beschaeftigen. Diese sind ein hoher energetischer Gesamtnutzungsgrad fuer Strom- und Waermeauskopplung, besonders bei optimierter Integration in den bestehenden Kraftwerkspark des EVU, Erweiterung des Kerngeschaeftes Stromversorgung durch Waermelieferung, dadurch auch verstaerkte Kundenbindung. Systemfuehrerschaft Energie bei moeglichst vollstaendiger Praesenz im lokal begrenzten Markt. Dargestellt werden Aktivitaeten, um den (Nischen-)Markt KWK im Wettbewerb erfolgreich zu besetzen (orig./RHM)

Operation management and network control in interconnected power supply companies - saving potentials, concepts, solutions; Betriebsfuehrung und Netzleittechnik in Querverbundunternehmen - Einsparpotentiale, Konzepte, Loesungen

Energy Technology Data Exchange (ETDEWEB)

Osswald, W.

1997-12-31

Most municipal power supply companies in Germany are horizontally integrated. To enhance their economic efficiency these companies are currently reorganising their traditional business sectors and preparing and developing new ones in the area of communal services. In this process every effort is made being made to introduce and use the full instrumentarium of modern information technology throughout the company as soon as possible. The restructuring process necessitates effectively reducing whatever objectively inevitable risks it entails and reliably solving arising conflicts. The present contribution relates some experiences from work on this project. [Deutsch] Kommunale Versorgungsunternehmen sind in Deutschland mehrheitlich Querverbundunternehmen. Aktuell werden in diesen Unternehmen die herkoemmlichen Geschaeftsbereiche zur Steigerung der wirtschaftlichen Effizienz reorganisiert und neue Geschaeftsfelder fuer kommunale Dienstleistungen vorbereitet und erschlossen. Dieser Prozess ist zugleich durch das Bemuehen gekennzeichnet, alle Moeglichkeiten der modernen Informationstechnik moeglichst schnell unternehmensweit einzufuehren und zu nutzen. Hierbei muessen objektiv gegebene Risiken wirksam begrenzt und auftretende Konflikte zuverlaessig geloest werden. Der vorliegende Beitrag vermittelt einige Erfahrungen aus der Projektarbeit. (orig./RHM)

Economic aspects of adaptation to the climate change. Bibliographic study on the cost and benefits of adaptation measures to cope with global climate change; Oekonomische Aspekte der Anpassung an den Klimawandel. Literaturauswertung zu Kosten und Nutzen von Anpassungsmassnahmen an den Klimawandel

Energy Technology Data Exchange (ETDEWEB)

Troeltzsch, Jenny; Goerlach, Benjamin [Ecologic gGmbH Institut fuer Internationale und Europaeische Umweltpolitik, Berlin (Germany); Lueckge, Helen; Peter, Martin [INFRAS - Forschung und Beratung, Zuerich (Switzerland); Sartorius, Christian [Fraunhofer-Institut fuer System- und Innovationsforschung (ISI), Karlsruhe (Germany)

2011-09-15

Measures for adaptation to the global climate change are a comparatively recent but highly complex field of economic investigation. Adaptation measures differ in many respects from measures to prevent emissions of greenhouse gases, and these differences are reflected in the methodology of economic analyses. For example, the evaluation of adaptation measures tends to depend more strongly on a concrete regional and time context. On the other hand, there is no single variable by which the effects of adaptation measures can be measured, and therefore there is no adaptation goal that is quantified (in time and volume). The contribution outlines certain aspects that have been identified as critical in the course of the process of literature compilation. This compilation does not intend to provide a final discussion of the problems inherent in an economic evaluation of adaptation measures; rather, it points out certain aspects that are relevant for understanding the available fields of action. (orig./RHM)

Energy industry law in the field of tension between freedom of the market and governmental restrictions; Energiewirtschaftrecht im Spannungsfeld von marktlicher Freiheit und hoheitlichen Einschraenkungen

Energy Technology Data Exchange (ETDEWEB)

Ehricke, Ulrich (ed.) [Koeln Univ. (Germany). Inst. fuer das Recht der Europaeischen Union; Koeln Univ. (Germany). Inst. fuer Energierecht

2011-07-01

The book contains the papers presented at the 39th annual meeting on energy law of the Institute of Energy Law of Cologne University, held on 4 November 2010: Problems of recommunalisation from the view of the communities as illustrated by the example of the Free and Hanseatic City of Hamburg; The development of market definition in the light of the market dynamics of the electricity and gas markets; Legal problems of long-term capacity bookings in the gas infrastructure; Interconnection of the European electricity markets, reality or chimera?; The European energy stock exchange in the point of intersection of energy regulation and bank supervision - current information on the development of the supervision regime for the energy market; Problems of the new energy competence title in Art. 194A EnV; Current rulings of the 3th cartel senate of the Duesseldorf Higher Regional Court on energy law; New lines for environmental protection: Obstacles to the grid integration of renewable energy sources. (orig./RHM)

Contract manual for the gas industry. Practically oriented drafting and legally compliant application; Vertragshandbuch Gaswirtschaft. Praxisgerechte Gestaltung und rechtssichere Anwendung

Energy Technology Data Exchange (ETDEWEB)

Baumgert, Caspar (ed.) [WEMAG AG, Schwerin (Germany)

2010-07-01

The handbook presents all contracts on the delivery and grid side, including their specific clauses and variants along the value chain. This includes base load and auxiliary supply, contracts for private, commercial and industrial special customers as well as re-distributors, metering contracts, grid contracts, storage contracts, and biogas and heat supply contracting. The legal problems are outlined clearly and easy to understand, and the following questions are answered: What are the boundary conditions set by the new energy industry law and general civil law? Inhowfar are the contents of contracts influenced by legal specifications? What options are available for contract drafting, and what are their consequences? What contents are of particular importance? What are the requirements that result from price regulation by civil and cartel law? What is the role of licence fees in product design? What are the chances and risks of innovative products? What options for reaction do providers have in case of (impending) customer insolvency? (orig./RHM)

Current algebra; Algebre des courants

Energy Technology Data Exchange (ETDEWEB)

Jacob, M [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1967-07-01

The first three chapters of these lecture notes are devoted to generalities concerning current algebra. The weak currents are defined, and their main properties given (V-A hypothesis, conserved vector current, selection rules, partially conserved axial current,...). The SU (3) x SU (3) algebra of Gell-Mann is introduced, and the general properties of the non-leptonic weak Hamiltonian are discussed. Chapters 4 to 9 are devoted to some important applications of the algebra. First one proves the Adler- Weisberger formula, in two different ways, by either the infinite momentum frame, or the near-by singularities method. In the others chapters, the latter method is the only one used. The following topics are successively dealt with: semi leptonic decays of K mesons and hyperons, Kroll- Ruderman theorem, non leptonic decays of K mesons and hyperons ( {delta}I = 1/2 rule), low energy theorems concerning processes with emission (or absorption) of a pion or a photon, super-convergence sum rules, and finally, neutrino reactions. (author) [French] La premiere partie de ce cours (trois premiers chapitres), traite des generalites concernant l'algebre de courants. Apres une definition rapide des courants faibles et un rappel de leurs proprietes (hypothese V-A, conservation du courant vecteur, regles de selection, courant axial partiellement conserve,...), l'on introduit l'algebre de Gell-Mann SU (3) x SU (3), et discute les proprietes generales de l'Hamiltonien faible non leptonique. Les chapitres IV a IX sont consacres a des applications importantes de l'algebre des courants. En premier lieu l'on demontre la formule de Adler et Weisberger, par deux methodes differentes, celle dite du repere de moment infini et celle des singularites proches. Cette derniere est seule utilisee dans la suite. Puis, l'on traite successivement les problemes suivants: desintegrations semi-leptoniques des mesons K et des hyperons, theoreme de Kroll-Ruderman, desintegrations non leptoniques des mesons

Multireference configuration interaction calculations of the first six ionization potentials of the uranium atom

Energy Technology Data Exchange (ETDEWEB)

Bross, David H.; Parmar, Payal; Peterson, Kirk A., E-mail: kipeters@wsu.edu [Department of Chemistry, Washington State University, Pullman, Washington 99164-4630 (United States)

2015-11-14

The first 6 ionization potentials (IPs) of the uranium atom have been calculated using multireference configuration interaction (MRCI+Q) with extrapolations to the complete basis set limit using new all-electron correlation consistent basis sets. The latter was carried out with the third-order Douglas-Kroll-Hess Hamiltonian. Correlation down through the 5s5p5d electrons has been taken into account, as well as contributions to the IPs due to the Lamb shift. Spin-orbit coupling contributions calculated at the 4-component Kramers restricted configuration interaction level, as well as the Gaunt term computed at the Dirac-Hartree-Fock level, were added to the best scalar relativistic results. The final ionization potentials are expected to be accurate to at least 5 kcal/mol (0.2 eV) and thus more reliable than the current experimental values of IP{sub 3} through IP{sub 6}.

Radiative corrections to e+e- reactions to all orders in α using the renormalization group

International Nuclear Information System (INIS)

Tsai, Y.S.

1983-01-01

Renormalization group technique is used to improve the accuracy of the lowest order radiative corrections in QED. The exponentiation of infrared terms comes automatically. It also leads to exponentiation of the vertex functions. It predicts the existence of conversion of photons into pairs and the result agrees with the Kroll-Wada relation. Kinoshita-Lee-Nauenberg cancellation of mass singularities occurs to all order in α in leading log approximation in the final state if we sum over all the final states. Higher order corrections to the order α 3 asymmetry is shown to be small. The results are used to derive useful formulas for the radiative corrections to processes such as e + e - → μ + μ - , e + e - → μ + μ - γ, e + e - → hadron continuum, e + e - → very narrow resonance such as phi, and e + e - → not very narrow resonance such as Z 0

High-resolution molybdenum K-edge X-ray absorption spectroscopy analyzed with time-dependent density functional theory.

Science.gov (United States)

Lima, Frederico A; Bjornsson, Ragnar; Weyhermüller, Thomas; Chandrasekaran, Perumalreddy; Glatzel, Pieter; Neese, Frank; DeBeer, Serena

2013-12-28

X-ray absorption spectroscopy (XAS) is a widely used experimental technique capable of selectively probing the local structure around an absorbing atomic species in molecules and materials. When applied to heavy elements, however, the quantitative interpretation can be challenging due to the intrinsic spectral broadening arising from the decrease in the core-hole lifetime. In this work we have used high-energy resolution fluorescence detected XAS (HERFD-XAS) to investigate a series of molybdenum complexes. The sharper spectral features obtained by HERFD-XAS measurements enable a clear assignment of the features present in the pre-edge region. Time-dependent density functional theory (TDDFT) has been previously shown to predict K-pre-edge XAS spectra of first row transition metal compounds with a reasonable degree of accuracy. Here we extend this approach to molybdenum K-edge HERFD-XAS and present the necessary calibration. Modern pure and hybrid functionals are utilized and relativistic effects are accounted for using either the Zeroth Order Regular Approximation (ZORA) or the second order Douglas-Kroll-Hess (DKH2) scalar relativistic approximations. We have found that both the predicted energies and intensities are in excellent agreement with experiment, independent of the functional used. The model chosen to account for relativistic effects also has little impact on the calculated spectra. This study provides an important calibration set for future applications of molybdenum HERFD-XAS to complex catalytic systems.

Optical absorption spectra and g factor of MgO: Mn2+explored by ab initio and semi empirical methods

Science.gov (United States)

Andreici Eftimie, E.-L.; Avram, C. N.; Brik, M. G.; Avram, N. M.

2018-02-01

In this paper we present a methodology for calculations of the optical absorption spectra, ligand field parameters and g factor for the Mn2+ (3d5) ions doped in MgO host crystal. The proposed technique combines two methods: the ab initio multireference (MR) and the semi empirical ligand field (LF) in the framework of the exchange charge model (ECM) respectively. Both methods of calculations are applied to the [MnO6]10-cluster embedded in an extended point charge field of host matrix ligands based on Gellé-Lepetit procedure. The first step of such investigations was the full optimization of the cubic structure of perfect MgO crystal, followed by the structural optimization of the doped of MgO:Mn2+ system, using periodic density functional theory (DFT). The ab initio MR wave functions approaches, such as complete active space self-consistent field (CASSCF), N-electron valence second order perturbation theory (NEVPT2) and spectroscopy oriented configuration interaction (SORCI), are used for the calculations. The scalar relativistic effects have also been taken into account through the second order Douglas-Kroll-Hess (DKH2) procedure. Ab initio ligand field theory (AILFT) allows to extract all LF parameters and spin-orbit coupling constant from such calculations. In addition, the ECM of ligand field theory (LFT) has been used for modelling theoptical absorption spectra. The perturbation theory (PT) was employed for the g factor calculation in the semi empirical LFT. The results of each of the aforementioned types of calculations are discussed and the comparisons between the results obtained and the experimental results show a reasonable agreement, which justifies this new methodology based on the simultaneous use of both methods. This study establishes fundamental principles for the further modelling of larger embedded cluster models of doped metal oxides.

Multiphoton (e,2e) process of hydrogen atom in strong laser field

Energy Technology Data Exchange (ETDEWEB)

Ghosh Deb, S.; Roy, S.; Sinha, C. [Indian Association for the Cultivation of Science, Dept. of Theoretical Physics, Jadavpur, Kolkata (India)

2009-12-15

The dynamics of the electron impact multiphoton ionization of a hydrogen atom in the presence of an intense laser field (e, n gamma e) has been studied theoretically for laser polarization parallel and perpendicular to the incident momentum, with a view to comparing (qualitatively) the results with the recent kinematically complete experiments of Hoehr et al. for the He target. Significant laser modifications are noted in the present doubly (DDCS) and the fully differential multiphoton cross sections (TDCS) for both the geometries (parallel and perpendicular). For most of the explored kinematics (chosen in accordance with the experiment), the present binary peak intensity of the laser-assisted multiphoton TDCS is significantly enhanced with respect to the field free ones, in qualitative agreement with the experiment. Importance of the multiphoton effects is also studied. The multiphoton cross sections in the zeroth order approximation of the ejected electron wavefunction (CV) obeys the Kroll Watson sum rule while it does not hold good in the corresponding first order approximation (MCV). (authors)

Current algebra

International Nuclear Information System (INIS)

Jacob, M.

1967-01-01

The first three chapters of these lecture notes are devoted to generalities concerning current algebra. The weak currents are defined, and their main properties given (V-A hypothesis, conserved vector current, selection rules, partially conserved axial current,...). The SU (3) x SU (3) algebra of Gell-Mann is introduced, and the general properties of the non-leptonic weak Hamiltonian are discussed. Chapters 4 to 9 are devoted to some important applications of the algebra. First one proves the Adler- Weisberger formula, in two different ways, by either the infinite momentum frame, or the near-by singularities method. In the others chapters, the latter method is the only one used. The following topics are successively dealt with: semi leptonic decays of K mesons and hyperons, Kroll- Ruderman theorem, non leptonic decays of K mesons and hyperons ( ΔI = 1/2 rule), low energy theorems concerning processes with emission (or absorption) of a pion or a photon, super-convergence sum rules, and finally, neutrino reactions. (author) [fr

Investigation on spectroscopic parameters and molecular constants of BeS(X1Σ+) using MRCI theory

International Nuclear Information System (INIS)

Liu Hui; Xing Wei; Shi Deheng; Sun Jinfeng

2012-01-01

The potential energy curve (PEC) of BeS(X 1 Σ + ) molecule has been studied using MRCI approach with Davidson modification in conjunction with the cc-pV5Z basis set. Effects on the PECs by the core-valence correlation corrections and relativistic effects have been taken into account. The way to consider the relativistic effects is to use the second-order Douglas-Kroll Hamiltonian approximation. With the PEC including the core-valence correlation corrections and relativistic effects, the spectroscopic parameters of BeS(X 1 Σ + ) have been determined. These parameters are compared in detail with those of previous studies reported in the literature, and excellent agreement has been found between the available experimental data and the present ones. With the PEC corrected, the first 40 vibrational states for the non-rotating BeS are computed, and the vibrational level, inertial rotation and centrifugal distortion constants for each vibrational state are predicted. (authors)

Proceedings of the 34th International Conference in High Energy Physics (ICHEP08), Philadelphia, PA, 2008

International Nuclear Information System (INIS)

Lockyer, Nigel S.; Smith, A.J. Stewart

2008-01-01

In 2004 a team from the University of Pennsylvania, Princeton University, and the Institute for Advanced Study proposed to host the 2008 International Conference on High Energy Physics (ICHEP) on the campus of the University of Pennsylvania in Philadelphia. The proposal was approved later that year by the C-11 committee of the International Union of Pure and Applied Physics. The Co-Chairs were Nigel S. Lockyer (U. Penn/TRIUMF) and A.J. Stewart Smith (Princeton); Joe Kroll of U. Penn served as Deputy Chair from 2007 on. Highlights of the proposal included 1. greatly increased participation of young scientists, women scientists, and graduate students 2. new emphasis on formal theory 3. increased focus on astrophysics and cosmology 4. large informal poster session (170 posters) in prime time 5. convenient, contiguous venues for all sessions and lodging 6. landmark locations for the reception and banquet. The conference program consisted of three days of parallel sessions and three days of plenary talks.

Mapping boron in silicon solar cells using electron energy-loss spectroscopy

DEFF Research Database (Denmark)

in the energies of plasmon peaks in the low loss region [5]. We use these approaches to characterize both a thick n-p junction and the 10-nm-thick p-doped layer of a working solar cell. [1] U. Kroll, C. Bucher, S. Benagli, I. Schönbächler, J. Meier, A. Shah, J. Ballutaud, A. Howling, Ch. Hollenstein, A. Büchel, M......Amorphous silicon solar cells typically consist of stacked layers deposited on plastic or metallic substrates making sample preparation for transmission electron microscopy (TEM) difficult. The amorphous silicon layer - the active part of the solar cell - is sandwiched between 10-nm-thick n- and p...... resolution using TEM is highly challenging [3]. Recently, scanning TEM (STEM) combined with electron energy-loss spectroscopy (EELS) and spherical aberration-correction has allowed the direct detection of dopant concentration of 10^20cm-3 in 65-nm-wide silicon devices [4]. Here, we prepare TEM samples...

How satisfied are the major customers of electric utilities?; Wie zufrieden sind die grossen Stromkunden?

Energy Technology Data Exchange (ETDEWEB)

Edelmann, H. [VEW Energie AG, Dortmund (Germany). Abt. Marktforschung und Volkswirtschaft

1998-07-27

In the liberalised electric power market, satisfying customers is a very important objective of utilities, as customers are free to enter into supply contracts with competitors in the market. Satisfaction of customers enhances customer loyalty, as many electric utilities know by now, but only few utilities have a clear picture of the level of satisfaction of their customers, and of their standing in their customers` opinion in comparison with other marketers. The article explains approaches and methods for a systematic and well-founded survey of customers and assessment of customer satisfaction. (orig./CB) [Deutsch] In einem liberalisierten Elektrizitaetsmarkt kommt der Kundenzufriedenheit eine zentrale Bedeutung zu. Diese ist massgebend dafuer, ob ein Kunde zu einem anderen Anbieter wechselt oder nicht. Hohe Kundenzufriedenheit bedeutet hohe Kundenbindung. Viele Stromversorger haben das bereits erkannt, doch nur bei wenigen existiert ein klares Bild darueber, wie zufrieden ihre Kunden tatsaechlich mit ihnen sind und wie sie im Vergleich zu anderen Stromversorgern stehen. Wie dargestellt wird, laesst sich ein solches Bild nur ueber eine systematische und fundierte Messung der Kundenzufriedenheit gewinnen. (orig./RHM)

Climate and energy

International Nuclear Information System (INIS)

Anon.

1996-01-01

The dossier on Climate and Energy encompasses contributions addressing the following topics: Climate research in Germany, perspectives of the energy of the future; Energy-conserving building design, construction and retrofitting; Companies developing ecological awareness and ecological performance; World population, energy consumption and greenhouse gas abatement; On the uncertainty involved in political evaluation of the global climate change; Economic aspects of the carbon dioxide issue; Ozone - polar stratospheres - clouds and ozone hole; Ozone - vertical ozone distribution in the antarctic region; Sudden climate change; Sulfate aerosols and climate change; Symptoms of the global climate change; IKARUS - greenhouse gas abatement strategies; Energy from fossil fuels; Renewable energy sources; Nuclear fusion; Is there a chance for nuclear energy?; Least-cost planning leading to energy-conserving power plants; Pleading for a sustainable energy economy; Why we both love and destroy nature. The concluding two contributions are interviews highlighting two statements: We will persist in our intention to achieve the declared objectives for greenhouse gas abatement, and: We cannot do without nuclear energy. (RHM) [de

Non-destructive testing of high pressure fibre reinforced composites tubes by computed tomography

Energy Technology Data Exchange (ETDEWEB)

Klimek, L. [Qualitaetszentrum Dortmund (Germany); Monstadt, H.; Boedecker, T. [EFMT, Bochum (Germany)

1995-12-31

For new applications of fibre reinforced composites, new non-destructive testing methods are required which on the one hand can be used as a quality testing method and on the other hand as an in-service inspection method during the life of a product. Special attention should be paid to the defect sensitivity and to a detailed classification of visible defects. Defining a detectable standard, comparable investigations were carried out using the Ultra Fast Scanner which is located at the Entwicklungs- und Forschungszentrum fuer Mikrotherapie gGmbH (EFMT) and the industrial scanner of the Qualitaetszentrum Dortmund GmbH u. Co. KG (QZ-DO). The investigation object is a high pressure tube which is made up of three different diameter structures. There can be distinguished between three types of tube layers. Digital image processing has been used to get more information form measured data. We developed two different types of digital image filters: A SIGMA and a Contrast Sensitive Weights (CSW) image filter and made a comparative study. (orig./RHM)

Correlation consistent basis sets for actinides. I. The Th and U atoms

Energy Technology Data Exchange (ETDEWEB)

Peterson, Kirk A., E-mail: kipeters@wsu.edu [Department of Chemistry, Washington State University, Pullman, Washington 99164-4630 (United States)

2015-02-21

New correlation consistent basis sets based on both pseudopotential (PP) and all-electron Douglas-Kroll-Hess (DKH) Hamiltonians have been developed from double- to quadruple-zeta quality for the actinide atoms thorium and uranium. Sets for valence electron correlation (5f6s6p6d), cc − pV nZ − PP and cc − pV nZ − DK3, as well as outer-core correlation (valence + 5s5p5d), cc − pwCV nZ − PP and cc − pwCV nZ − DK3, are reported (n = D, T, Q). The -PP sets are constructed in conjunction with small-core, 60-electron PPs, while the -DK3 sets utilized the 3rd-order Douglas-Kroll-Hess scalar relativistic Hamiltonian. Both series of basis sets show systematic convergence towards the complete basis set limit, both at the Hartree-Fock and correlated levels of theory, making them amenable to standard basis set extrapolation techniques. To assess the utility of the new basis sets, extensive coupled cluster composite thermochemistry calculations of ThF{sub n} (n = 2 − 4), ThO{sub 2}, and UF{sub n} (n = 4 − 6) have been carried out. After accurately accounting for valence and outer-core correlation, spin-orbit coupling, and even Lamb shift effects, the final 298 K atomization enthalpies of ThF{sub 4}, ThF{sub 3}, ThF{sub 2}, and ThO{sub 2} are all within their experimental uncertainties. Bond dissociation energies of ThF{sub 4} and ThF{sub 3}, as well as UF{sub 6} and UF{sub 5}, were similarly accurate. The derived enthalpies of formation for these species also showed a very satisfactory agreement with experiment, demonstrating that the new basis sets allow for the use of accurate composite schemes just as in molecular systems composed only of lighter atoms. The differences between the PP and DK3 approaches were found to increase with the change in formal oxidation state on the actinide atom, approaching 5-6 kcal/mol for the atomization enthalpies of ThF{sub 4} and ThO{sub 2}. The DKH3 atomization energy of ThO{sub 2} was calculated to be smaller than the DKH2

Theoretical study of actinide monocarbides (ThC, UC, PuC, and AmC)

Science.gov (United States)

Pogány, Peter; Kovács, Attila; Visscher, Lucas; Konings, Rudy J. M.

2016-12-01

A study of four representative actinide monocarbides, ThC, UC, PuC, and AmC, has been performed with relativistic quantum chemical calculations. The two applied methods were multireference complete active space second-order perturbation theory (CASPT2) including the Douglas-Kroll-Hess Hamiltonian with all-electron basis sets and density functional theory with the B3LYP exchange-correlation functional in conjunction with relativistic pseudopotentials. Beside the ground electronic states, the excited states up to 17 000 cm-1 have been determined. The molecular properties explored included the ground-state geometries, bonding properties, and the electronic absorption spectra. According to the occupation of the bonding orbitals, the calculated electronic states were classified into three groups, each leading to a characteristic bond distance range for the equilibrium geometry. The ground states of ThC, UC, and PuC have two doubly occupied π orbitals resulting in short bond distances between 1.8 and 2.0 Å, whereas the ground state of AmC has significant occupation of the antibonding orbitals, causing a bond distance of 2.15 Å.

THE FORENSIC ACCOUNTING AND CORPORATE FRAUD

Directory of Open Access Journals (Sweden)

Joshua Onome Imoniana

2013-04-01

Full Text Available This study is aimed at analyzing the characteristics of forensic accounting services performed by the accounting firms in Brazil, using an exploratory approach. At the end, performs a discourse analysis on a speech proffered by the CEO of one of the key players of forensic accounting service provider (Kroll in Brazil. In order to orientate this reflection, we pose the following question: what is the characteristic of forensic accounting that substantiates it as professional accountants’ innovation to curb corporate accounting malpractices? In this intent, we accept the premise that the bone of contention in some unhealthy business environment is the inability of auditor to track frauds. We used the icons (categories and/or nodes that dynamically represent formalism in the theory of self re-production to explain the patterns met in the speech. Our finding makes us to conclude that the idea that frauds have been least detected by auditors begins to gain shape as auditors are more adequately trained to detect fraud instead of emphasizing the traditional segregation of duties and safeguard of assets.

Process for purifying zirconium sponge

International Nuclear Information System (INIS)

Abodishish, H.A.M.; Kimball, L.S.

1992-01-01

This patent describes a Kroll reduction process wherein a zirconium sponge contaminated with unreacted magnesium and by-product magnesium chloride is produced as a regulus, a process for purifying the zirconium sponge. It comprises: distilling magnesium and magnesium chloride from: a regulus containing a zirconium sponge and magnesium and magnesium chloride at a temperature above about 800 degrees C and at an absolute pressure less than about 10 mmHg in a distillation vessel to purify the zirconium sponge; condensing the magnesium and the magnesium chloride distilled from the zirconium sponge in a condenser; and then backfilling the vessel containing the zirconium sponge and the condenser containing the magnesium and the magnesium chloride with a gas; recirculating the gas between the vessel and the condenser to cool the zirconium sponge from above about 800 degrees C to below about 300 degrees C; and cooling the recirculating gas in the condenser containing the condensed magnesium and the condensed magnesium chloride as the gas cools the zirconium sponge to below about 300 degrees C

Titanium metal: extraction to application

Energy Technology Data Exchange (ETDEWEB)

Gambogi, Joseph (USGS, Reston, VA); Gerdemann, Stephen J.

2002-09-01

In 1998, approximately 57,000 tons of titanium metal was consumed in the form of mill products (1). Only about 5% of the 4 million tons of titanium minerals consumed each year is used to produce titanium metal, with the remainder primarily used to produce titanium dioxide pigment. Titanium metal production is primarily based on the direct chlorination of rutile to produce titanium tetrachloride, which is then reduced to metal using the Kroll magnesium reduction process. The use of titanium is tied to its high strength-to-weight ratio and corrosion resistance. Aerospace is the largest application for titanium. In this paper, we discuss all aspects of the titanium industry from ore deposits through extraction to present and future applications. The methods of both primary (mining of ore, extraction, and purification) and secondary (forming and machining) operations will be analyzed. The chemical and physical properties of titanium metal will be briefly examined. Present and future applications for titanium will be discussed. Finally, the economics of titanium metal production also are analyzed as well as the advantages and disadvantages of various alternative extraction methods.

Il "complesso di Louise": la mostra Tempo libero (13. Triennale, Milano 1964, dentro e fuori dal Palazzo

Directory of Open Access Journals (Sweden)

Francesca Zanella

2012-01-01

Full Text Available «Il “complesso di Louise” aleggia sulla Triennale: intendo ovviamente riferirmi a Louise Nevelson [...] per l’intero processo di ‘riempimento’ operato dagli allestitori nei confronti del palazzo di Giovanni Muzio, sede ormai deprecata di questa manifestazione» (Tentori 1964, p. 49. This is the Francesco Tentori’s review on the 13th Triennale exhibition in Milan on Leisure. The Louise Nevelson sculptures become a metaphore of the dialogue between layout, objects, images and Giovanni Muzio’s architecture. This is one of the crucial themes of the exhibition that has been pointed out as one of the most significant experiment for the dialogue between visual arts and exhibit design in the main and theoretical area. An other element of interest is the interaction between the central section and national displays. The Great Britain section is one of the most interesting for the ‘pop’ visualization of the theme designed by Theo Crosby, with contributions of Natasha Kroll and Fletcher Forbes e Gill, and Joe Tilson, Eduardo Paolozzi, Peter Startup, Barnet Saidman, Roger Mayne, Johnny Scott, Harold Cohen.

Study of the picture change error at the 2nd order Douglas Kroll Hess level of theory. Electron and spin density and structure factors of the Bis[bis(methoxycarbimido) aminato] copper (II) complex

International Nuclear Information System (INIS)

Bučinský, Lukáš; Biskupič, Stanislav; Jayatilaka, Dylan

2012-01-01

Graphical abstract: The dependence of the radial distribution of the spin density in the vicinity of the nucleus on the formal oxidation state of the copper atom is shown on the top three figures. Note also the large impact of PCE as well as relativistic effects. The bottom three figures present the relativistic effects and PCE in the electron density of the [CuL 2 ] model compound (of the size 1 bohr 2 ). PCE is very little affecting the relativistic effects in the electron density close to the nucleus of copper atom, i.e. the PCE in the relativistic effects of the electron density are hardly discernable in the case of compounds containing copper. Highlights: ► The extent of PCE in a model compound containing copper atom is presented. ► The spin/electron density along bond the Cu–N is the most affected by PCE only at the nucleus of the copper atom. ► The 2D inspection of relativistic effects in electron/spin densities is not sensitive to PCE. ► Structure factors are an order of magnitude less affected by PCE than by relativistic effects. ► PCE in the Mulliken populations and spin contamination is considered. - Abstract: The analytic correction and the extent of the picture change error (PCE) at the scalar 2nd order Douglas–Kroll–Hess level of theory is considered. The one-dimensional (1D), two-dimensional (2D) spin/electron densities and/or difference densities, structure factors and Mulliken populations of the Bis [bis-(methoxycarbimido) aminato] copper (II) model compound are presented. For further comparison the radial distributions of the electron and spin density of the copper atom (as well as of the copper di-cation) are presented. In addition, the infinite order two component (IOTC) radial distributions of electron and spin density of the copper atom and copper dication are presented as well. The PCE is almost hidden in the 2D densities of the studied model compound. The 1D electron/spin difference densities along the Cu–N bond show the

Enhancement of security using structured phase masked in optical image encryption on Fresnel transform domain

Science.gov (United States)

Yadav, Poonam Lata; Singh, Hukum

2018-05-01

To enhance the security in optical image encryption system and to protect it from the attackers, this paper proposes new digital spiral phase mask based on Fresnel Transform. In this cryptosystem the Spiral Phase Mask (SPM) used is a hybrid of Fresnel Zone Plate (FZP) and Radial Hilbert Mask (RHM) which makes the key strong and enhances the security. The different keys used for encryption and decryption purposed make the system much more secure. Proposed scheme uses various structured phase mask which increases the key space also it increases the number of parameters which makes it difficult for the attackers to exactly find the key to recover the original image. We have also used different keys for encryption and decryption purpose to make the system much more secure. The strength of the proposed cryptosystem has been analyzed by simulating on MATLAB 7.9.0(R2008a). Mean Square Errors (MSE) and Peak Signal to Noise Ratio (PSNR) are calculated for the proposed algorithm. The experimental results are provided to highlight the effectiveness and sustainability of proposed cryptosystem and to prove that the cryptosystem is secure for usage.

Energy for Germany 2010. US energy policy; Energie fuer Deutschland 2010. Energiepolitik der USA

Energy Technology Data Exchange (ETDEWEB)

NONE

2010-06-15

This is a publication of the Weltenergierat-Deutschland e.V. (World Energy Council), Berlin, dealing with US energy policy. In particular, it presents the energy-political boundary conditions and challenges, the energy policy of the USA and an outlook to the future: While Obama's energy policy is giving room for transatlantic cooperations, obstacles will remain. There is a chapter on energy and the world, which goes into the following issues: World Energy Outlook 2009 of the International Energy Agency (IEA); Copenhagen from thew view of the World Energy Council; Desertec; CCS implementation worldwide; ''Yasun: ITT'' - Ecuador. The chapter on energy in Europe discusses the following subjects: Priorities of the energy policy of the new EU Commission; EEX and coupling points; the third EU energy package for the internal market; Green power certificates (EWI study); Nuclear power: New power plant construction projects and operating times of existing powerplants in Europe; EU directive on gas supply reliability; Regional cooperations for assuring reliability of supply. The final chapter informs on energy in Germany: Long-term geological storage of CO2 in Germany; Electromobility; Vulnerability and reliability of supply as indicators of assured energy supply. (orig./RHM)

Energy for Germany 2010. US energy policy; Energie fuer Deutschland 2010. Energiepolitik der USA

Energy Technology Data Exchange (ETDEWEB)

NONE

2010-06-15

This is a publication of the Weltenergierat-Deutschland e.V. (World Energy Council), Berlin, dealing with US energy policy. In particular, it presents the energy-political boundary conditions and challenges, the energy policy of the USA and an outlook to the future: While Obama's energy policy is giving room for transatlantic cooperations, obstacles will remain. There is a chapter on energy and the world, which goes into the following issues: World Energy Outlook 2009 of the International Energy Agency (IEA); Copenhagen from thew view of the World Energy Council; Desertec; CCS implementation worldwide; ''Yasun: ITT'' - Ecuador. The chapter on energy in Europe discusses the following subjects: Priorities of the energy policy of the new EU Commission; EEX and coupling points; the third EU energy package for the internal market; Green power certificates (EWI study); Nuclear power: New power plant construction projects and operating times of existing powerplants in Europe; EU directive on gas supply reliability; Regional cooperations for assuring reliability of supply. The final chapter informs on energy in Germany: Long-term geological storage of CO2 in Germany; Electromobility; Vulnerability and reliability of supply as indicators of assured energy supply. (orig./RHM)

Records Group. The problem of fonds in the American archival studies

Directory of Open Access Journals (Sweden)

Bartosz Nowożycki

2017-12-01

Full Text Available The term record group means a group of fonds (records and it is a type of archival fonds rarely described in Polish archival literature. Most often it is associated with the complex archival fonds, due to its comlicated structure and blurred borderlines – an effect of administrative system varying from the Polish one. The post-war attempts to modify and broaden the meaning of the complex fonds caused its resemblance to the term record group. Irena Radtke in her paper given during the 6th Archival Methods Conference in Warsaw in 1970 proposed, that the complex fonds should be one comprising records of foreign provenance that are an effect of passive succession. Bohdan Ryszewski, addressing Radtke’s idea, noticed that passive succession might be a source of complications. However, this conceptualization of the definition of the complex fonds did not correspond with the American understanding of it as an above-fonds structure.Bogdan Kroll has touched the core of the problem; he noticed that an archival construction comprising materials of various provenances cannot be seen neither as an archival fonds, nor as a complex fonds. He saw a discrepancy between the structure and partition of archival holdings and archival theory; thus Kroll proposed abandoning the term complex fonds and implementation of the term archival complex. The archival complex was supposed to be archival materials of various origins merged (in or outside of an archive into fonds, or parts of archival fonds of different institutions having the same characteristic – function. The complex was supposed to make up a separate entity in logic structure of archival holdings, comprising of all archival fonds and/or their pieces being parts of the main fonds of the complex. The problem of lack of above-fonds forms in the Polish archival theory has been also noticed by Józef Siemieński, who has formulated the term of higher-order fonds. According to his idea the higher

Probing gluon saturation with next-to-leading order photon production at central rapidities in proton-nucleus collisions

Energy Technology Data Exchange (ETDEWEB)

Benić, Sanjin [Physics Department, Faculty of Science, University of Zagreb,Zagreb 10000 (Croatia); Department of Physics, The University of Tokyo,7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Fukushima, Kenji [Department of Physics, The University of Tokyo,7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Garcia-Montero, Oscar [Institut für Theoretische Physik, Universität Heidelberg,Philosophenweg 16, 69120 Heidelberg (Germany); Venugopalan, Raju [Physics Department, Brookhaven National Laboratory,Bldg. 510A, Upton, NY 11973 (United States)

2017-01-26

We compute the cross section for photons emitted from sea quarks in proton-nucleus collisions at collider energies. The computation is performed within the dilute-dense kinematics of the Color Glass Condensate (CGC) effective field theory. Albeit the result obtained is formally at next-to-leading order in the CGC power counting, it provides the dominant contribution for central rapidities. We observe that the inclusive photon cross section is proportional to all-twist Wilson line correlators in the nucleus. These correlators also appear in quark-pair production; unlike the latter, photon production is insensitive to hadronization uncertainties and therefore more sensitive to multi-parton correlations in the gluon saturation regime of QCD. We demonstrate that k{sub ⊥} and collinear factorized expressions for inclusive photon production are obtained as leading twist approximations to our result. In particular, the collinearly factorized expression is directly sensitive to the nuclear gluon distribution at small x. Other results of interest include the realization of the Low-Burnett-Kroll soft photon theorem in the CGC framework and a comparative study of how the photon amplitude is obtained in Lorenz and light-cone gauges.

Molecular and electronic structures of oxo-bis(benzene-1,2-dithiolato)chromate(V) monoanions. A combined experimental and density functional study.

Science.gov (United States)

Kapre, Ruta; Ray, Kallol; Sylvestre, Isabelle; Weyhermüller, Thomas; DeBeer George, Serena; Neese, Frank; Wieghardt, Karl

2006-05-01

Two oxo-bis(benzene-1,2-dithiolato)chromate(V) complexes, namely, [CrO(L(Bu))2]1- and [CrO(L(Me))2]1-, have been synthesized and studied by UV-vis, EPR, magnetic circular dichroism (MCD), and X-ray absorption spectroscopy and by X-ray crystallography; their electro- and magnetochemistries are reported. H2L(Bu) represents the pro-ligand 3,5-di-tert-butylbenzene-1,2-dithiol, and H2L(Me) is the corresponding 4-methyl-benzene-1,2-dithiol. A structural feature of interest for both the complexes is the folding of the dithiolate ligands about the S-S vector providing Cs symmetry to the complexes. Geometry optimizations using all-electron density functional theory with scalar relativistic corrections at the second-order Douglas-Kroll-Hess (DKH2) and zeroth-order regular approximation (ZORA) levels result in excellent agreement with the experimentally determined structures and electronic and S K-edge X-ray absorption spectra. From DFT calculations, the Cs instead of C2v symmetry for the complexes is attributed to the strong S(3p) --> Cr(3d(x2-y2)) pi-donation in Cs geometry providing additional stability to the complexes.

XZP + 1d and XZP + 1d-DKH basis sets for second-row elements: application to CCSD(T) zero-point vibrational energy and atomization energy calculations.

Science.gov (United States)

Campos, Cesar T; Jorge, Francisco E; Alves, Júlia M A

2012-09-01

Recently, segmented all-electron contracted double, triple, quadruple, quintuple, and sextuple zeta valence plus polarization function (XZP, X = D, T, Q, 5, and 6) basis sets for the elements from H to Ar were constructed for use in conjunction with nonrelativistic and Douglas-Kroll-Hess Hamiltonians. In this work, in order to obtain a better description of some molecular properties, the XZP sets for the second-row elements were augmented with high-exponent d "inner polarization functions," which were optimized in the molecular environment at the second-order Møller-Plesset level. At the coupled cluster level of theory, the inclusion of tight d functions for these elements was found to be essential to improve the agreement between theoretical and experimental zero-point vibrational energies (ZPVEs) and atomization energies. For all of the molecules studied, the ZPVE errors were always smaller than 0.5 %. The atomization energies were also improved by applying corrections due to core/valence correlation and atomic spin-orbit effects. This led to estimates for the atomization energies of various compounds in the gaseous phase. The largest error (1.2 kcal mol(-1)) was found for SiH(4).

Separation of Dirac's Hamiltonian by Van Vleck transformation

Science.gov (United States)

Jørgensen, Flemming

2017-01-01

The now classic Foldy-Wouthuysen transformation (FWT) was introduced as successive unitary transformations. This fundamental idea has become the standard in later developments such as the Douglas-Kroll transformation (DKT) - but it is not the only possibility. FWT can be seen as a simple special case of the general Van Vleck transformation (VVT) which besides the successive version has another, known as the canonical because of a series of nice mathematical properties discovered gradually over time. The aim of the present paper is to compare the two approaches - which give identical results in the lower orders, but not in the higher. After having recapitalised both, we apply them to Dirac's Hamiltonian for the electron in a constant electromagnetic field, written with so few assumptions about the operators that the mathematical techniques stand out separated from the terminology of relativistic quantum mechanics. FWT for a free particle is dealt with by a recent geometric approach to VVT. The original FWT is continued through the next non-zero orders. DKT is considered with special weight on equivalent formulations of the generalised and the optimised forms introduced by Wolf, Reiher and Hess.

A Survey of Utopia—Creating Filmic Travelogues in Architectural Design Studio Education †

Directory of Open Access Journals (Sweden)

Johannes Müntinga

2018-02-01

Full Text Available This paper investigates the potential of the creation of filmic travelogues in architectural design studio education. It looks at student works from a studio conducted at RWTH Aachen University in the summer term of 2017 and explores how the works construct meaning from and reflect on architectural reference in an active creative process. The assignment of the studio was to create a travelogue of a 4-day excursion to Belgium and the South of England in the form of a short film. Inspired by Patrick Keiller’s film Robinson in Space, the students were invited to explore the Situationist techniques of Drifting and Psychogeography, and to use them in their visual storytelling. The studio´s title A Survey of Utopia makes reference to the architectural and urbanistic projects that were visited: visionary residential projects from the 1960s to 1980s, built by well-known architects of this period, such as Lucien Kroll, Walter Segal and Leon Krier. The term utopia hints at the projects shared interest in radical change and bold new architectural approaches, even though each pursues its own distinct kind of utopia.

Multiphoton effects in laser-assisted ionization of a helium atom by electron impact

Energy Technology Data Exchange (ETDEWEB)

Ghosh Deb, S.; Sinha, C. [Department of Theoretical Physics, Indian association for the Cultivation of Science, Jadavpur, Kokata (India)

2010-11-15

The dynamics of the electron impact multiphoton ionization of a He atom in the presence of an intense laser field (n{gamma}{sub e}, 2e) is studied theoretically for laser polarization (||{sup l}) and perpendicular to the incident momentum. The triple differential (TDCS) as well as the double differential (DDCS) cross sections are studied for the coplanar asymmetric geometry. The results are compared with the only available kinematically complete experiment at high incident energy (1000 eV). Significant laser modification (enhancement) is noted due to multiphoton effects in the present binary and recoil peak intensities of the TDCS for both the geometries, in qualitative agreement with the experiment. In the single photon case, the net effect of the laser field is to suppress the field free (FF) TDCS as well as the DDCS in the zeroth order approximation of the ejected electron wave function (CV), while in the first order (MCV), the cross sections are found to be enhanced. The CV multiphoton cross sections obey the famous Kroll Watson (KW) sum rule while the latter does not hold good in the corresponding MCV approximation. (authors)

Microhydration of caesium compounds: Cs, CsOH, CsI and Cs₂I₂ complexes with one to three H₂O molecules of nuclear safety interest.

Science.gov (United States)

Sudolská, Mária; Cantrel, Laurent; Cernušák, Ivan

2014-04-01

Structure and thermodynamic properties (standard enthalpies of formation and Gibbs free energies) of hydrated caesium species of nuclear safety interest, Cs, CsOH, CsI and its dimer Cs₂I₂, with one up to three water molecules, are calculated to assess their possible existence in severe accident occurring to a pressurized water reactor. The calculations were performed using the coupled cluster theory including single, double and non-iterative triple substitutions (CCSD(T)) in conjunction with the basis sets (ANO-RCC) developed for scalar relativistic calculations. The second-order spin-free Douglas-Kroll-Hess Hamiltonian was used to account for the scalar relativistic effects. Thermodynamic properties obtained by these correlated ab initio calculations (entropies and thermal capacities at constant pressure as a function of temperature) are used in nuclear accident simulations using ASTEC/SOPHAEROS software. Interaction energies, standard enthalpies and Gibbs free energies of successive water molecules addition determine the ordering of the complexes. CsOH forms the most hydrated stable complexes followed by CsI, Cs₂I₂, and Cs. CsOH still exists in steam atmosphere even at quite high temperature, up to around 1100 K.

Local unitary transformation method for large-scale two-component relativistic calculations. II. Extension to two-electron Coulomb interaction.

Science.gov (United States)

Seino, Junji; Nakai, Hiromi

2012-10-14

The local unitary transformation (LUT) scheme at the spin-free infinite-order Douglas-Kroll-Hess (IODKH) level [J. Seino and H. Nakai, J. Chem. Phys. 136, 244102 (2012)], which is based on the locality of relativistic effects, has been extended to a four-component Dirac-Coulomb Hamiltonian. In the previous study, the LUT scheme was applied only to a one-particle IODKH Hamiltonian with non-relativistic two-electron Coulomb interaction, termed IODKH/C. The current study extends the LUT scheme to a two-particle IODKH Hamiltonian as well as one-particle one, termed IODKH/IODKH, which has been a real bottleneck in numerical calculation. The LUT scheme with the IODKH/IODKH Hamiltonian was numerically assessed in the diatomic molecules HX and X(2) and hydrogen halide molecules, (HX)(n) (X = F, Cl, Br, and I). The total Hartree-Fock energies calculated by the LUT method agree well with conventional IODKH/IODKH results. The computational cost of the LUT method is reduced drastically compared with that of the conventional method. In addition, the LUT method achieves linear-scaling with respect to the system size and a small prefactor.

Examples illustrating the effects of high-temperature corrosion and protective coatings on the creep-to-rupture behaviour of materials resistant to very high temperatures

International Nuclear Information System (INIS)

Sachova, E.; Hougardy, H.P.; Granacher, J.

1989-01-01

Assessing the creep stress, it is assumed in general that the sub-surface effects in a specimen correspond to those at the surface. Particularly in very high temperature environments, however, oxidation is an additional effect to be taken into account, and there are other operational stresses to be reckoned with, as e.g. hot gas corrosion of gas turbine blades. The reduction of the effective cross section due to corrosion for instance of the material affected by long-term creep leads to an increase in stresses and thus shortens the period up to rupture. Protective coatings will prevent or at least delay corrosion. The paper reports the performance of various protective coatings. Pt-Al coatings have have been found to remain intact even on specimens with the longest testing periods up to rupture, to an extent that there was no oxidation at the grain boundaries proceeding from the surface to the sub-surface material. The same applies to the plasma-sprayed coatings, although in some cases pores had developed in the coating. The chromium alitizations were used up irregularly over the surface of some specimens tested at 1000deg C. Chromizing layers have been found to be more strongly damaged than the other coatings tested under comparable conditions. (orig./RHM) [de

Effects of an operation management system on maintenance and store management; Auswirkungen eines Betriebsfuehrungsmanagements auf die Instandhaltung und Lagerwirtschaft

Energy Technology Data Exchange (ETDEWEB)

Stebel, H.

1997-12-31

The present paper describes a computer-aided operation management system for maintenance and store management whose purpose is to enhance operating efficiency and secure long-term profitability. The intent of STEAG AG in developing and introducing its SI operation management system was to improve the organisational efficiency of its operation management. Specifically designed for use in power supply, waste incineration and recycling plants STEAG`s SI operation management system has proven its value through many years of operation. The SI operation management system makes cost reduction potentials in many areas capable of exploitation. This applies in particular to labour input for administrative work and to materials management. [Deutsch] Durch die Einfuehrung eines geeigneten DV-gestuetzten Betriebsfuehrungssystems in der Instandhaltung und in der Lagerwirtschaft soll die Effizienz der Betriebsfuehrung gesteigert und das Betriebsergebnis langfristig gesichert werden. Fuer die Verbesserung der Effizienz der Betriebsfuehrungsorganisation hat STEAG AG das Betriebsfuehrungssystem SI entwickelt und eingefuehrt. Das STEAG-Betriebsfuehrungssystem SI ist speziell fuer den Einsatz in Energieversorgungs-, Muellverbrennungs- und Abfallverwertungsanlagen konzipiert und hat sich in langjaehrigem Einsatz in der Praxis bewaehrt. Durch Einsatz des Betriebsfuehrungssystems SI sind Kostensenkungspotentiale in vielen Bereichen realisierbar. Der Schwerpunkt liegt bei der Reduzierung der Zeiten zur administrativen Bearbeitung und bei den Bestaenden der Materialwirtschaft. (orig./RHM)

Operation management in the tension field between technical, commercial, and public legal demands; Betriebsfuehrung im Spannungsfeld technischer, kommerzieller und oeffentlich-rechtlicher Anforderungen

Energy Technology Data Exchange (ETDEWEB)

Stebel, H.

1997-12-31

Operation management is not restricted to the execution of operational measures. In order to be able to work together efficiently the different organisational units of a plant are dependent on the support of an intelligent operation management system. Such an operation management system must give the user`s working style priority over the system`s integration in the superordinate system. This is the only way to win the user`s acceptance and achieve the intended results now and over the long term. The most important thing to consider when planning the introduction of an operation management system are the likely processing costs. The one-time cost of procuring the necessary software is practically negligible. [Deutsch] Betriebsfuehrung ist keine ausschliesslich auf die Abwicklung der betrieblichen Massnahmen ausgerichtete Aufgabe. Die Organisationseinheiten des Betriebes muessen zur rationellen Bearbeitung durch ein intelligentes Betriebsfuehrungssystem unterstuetzt werden. Dieses Betriebsfuehrungssystem hat die Arbeitsweisen der Anwender vor die Integration des Systems in uebergeordnete Gesamtsysteme zu stellen. Nur so kann die Akzeptanz der Anwender erzielt sowie das geforderte Ergebnis erreicht und langfristig gesichert werden. Bei der Einfuehrung eines Betriebsfuehrungssystems sind insbesondere die langfristig zu erwartenden Bearbeitungskosten zu bewerten. Die einmaligen Anschaffungskosten der Software sind in Relation zu den Gesamtkosten praktisch ohne Bedeutung. (orig./RHM)

Studies on the influence of processing methods on the corrosion characteristics of electroslag-tape-plating with NiMo16Cr16Ti. Untersuchungen zum Einfluss der Prozessfuehrung auf die Korrosionseigenschaften beim Elektroschlacke-Bandplattieren mit NiMo16Cr16Ti

Energy Technology Data Exchange (ETDEWEB)

Blum, J

1991-01-01

The aim of the project was to demonstrate an economic possibility of using NiMo16Cr16Ti reliably as a plating material with simple to use methods. For this, the electroslag and submerged arc welding with tape electrodes as a coating technology are compared with each other. As the research showed, it is possible to coat large surface area, thick walled components economically with NiMo16Cr16Ti using electroslag (RES) tape plating. The choice of powder is important for the hot crack freedom and the precipitation poverty and thus the corrosion resistance of the plating. The silicon content was proved to be of importance in the plating. With the right choice of powder, the second layer already possesses the endurance of laminated materials against intercrystalline corrosion in coating tests as well as against pitting in a 10% FeCl{sub 3} solution. The coating capability lies at 0.5 m{sup 2}/h. - In addition the use of video thermography for on-line surveillance of seam on RES plates is documented. The evaluation of the pictures makes possible the targeting of the external magnets and thus the influencing of the melting bath flux. (orig./RHM) With 80 figs., 12 tabs.

Quota regime for renewable energy sources and Green Labels trading in the electricity market of the Netherlands

International Nuclear Information System (INIS)

Drillisch, J.

1998-01-01

The renewables quota regime combined with a ''green electricity'' labelling and trading system, implemented by the Dutch association of distribution undertakings, is the first of its kind in Europe. The distribution undertakings are bound by a commitment to take and distribute ''green label'' electricity from renewables amounting to approx. 3% of their total sales to contractual customers. This is a modest percentage, but the quota regime already proved to be a promoter of close-to-the-market generation technologies. It would be too early now to make a final statement on the quota regime's influence on enhanced use of renewable energy sources. Practice so far also revealed the need for some modifications in the design of the pricing system for''green electricity''. Current debates consider integration of renewable energy sources abroad. The first accounting date for giving evidence of compliance with the commitment to green label quotas is late in the year 2000. This will be the test for the system and the efficiency of sanctions provided for in case of non-compliance. It will be a task of the future to examine whether it might be appropriate to establish a similar system for the heat market. (RHM/CB) [de

Sustainable prevention of resource conflicts. Conflict risks for access and use of raw materials (report 1); Rohstoffkonflikte nachhaltig vermeiden. Konfliktrisiken bei Zugang und Nutzung von Rohstoffen (Teilbericht 1)

Energy Technology Data Exchange (ETDEWEB)

Taenzler, Dennis; Westerkamp, Meike [Adelphi Research, Berlin (Germany); Supersberger, Nikolaus; Ritthoff, Michael; Bleischwitz, Raimund [Wuppertal Institut fuer Klima, Umwelt, Energie GmbH, Wuppertal (Germany)

2011-04-15

Inequalities of resources ownership and the consequences of the exploitation of non-renewable resources have always caused violent conflicts of varying intensity. The resulting interdependence between conflicts on the one hand and resources on the other hand - discussed here under the term of conflict-resources nexus - is complex and requires a detailed theoretical and conceptional assessment. The risks of conflict vary as a function of the constellations of actors and the existing political, economic and social boundary conditions. These risks are often globally linked and reflect the flow of resources between consumer countries, transit countries, and producer countries. Conflicts in producer countries may endanger the supply of raw materials to consumer countries. Whether the raw material is an energetic resource like natural gas, petroleum, or coal, or a non-energetic resource like coltane or copper: There are many who demand that Germany should adapt to stronger competition and shorter supply and should also be aware of the possibility of conflicts about raw materials. This part-report of the project 'Sustainable Prevention of Resource Conflicts' presents important theoretical and conceptional considerations on the risk of conflict in the raw materials sector. On this basis, further reports will present case studies, scenarios, and preventive strategies. (orig./RHM)

Nanoporous hydroxyapatite/sodium titanate bilayer on titanium implants for improved osteointegration.

Science.gov (United States)

Carradò, A; Perrin-Schmitt, F; Le, Q V; Giraudel, M; Fischer, C; Koenig, G; Jacomine, L; Behr, L; Chalom, A; Fiette, L; Morlet, A; Pourroy, G

2017-03-01

The aim of this study was to improve the strength and quality of the titanium-hydroxyapatite interface in order to prevent long-term failure of the implanted devices originating from coating delamination and to test it in an in-vivo model. Ti disks and dental commercial implants were etched in Kroll solution. Thermochemical treatments of the acid-etched titanium were combined with sol-gel hydroxyapatite (HA) coating processes to obtain a nanoporous hydroxyapatite/sodium titanate bilayer. The sodium titanate layer was created by incorporating sodium ions onto the Ti surface during a NaOH alkaline treatment and stabilized using a heat treatment. HA layer was added by dip-coating in a sol-gel solution. The bioactivity was assessed in vitro with murine MC3T3-E1 and human SaOs-2 cells. Functional and histopathological evaluations of the coated Ti implants were performed at 22, 34 and 60days of implantation in a dog lower mandible model. Nanoporous hydroxyapatite/sodium titanate bilayer on titanium implants was sensitive neither to crack propagation nor to layer delamination. The in vitro results on murine MC3T3-E1 and human SaOs-2 cells confirm the advantage of this coating regarding the capacity of cell growth and differentiation. Signs of progressive bone incorporation, such as cancellous bone formed in contact with the implant over the existing compact bone, were notable as early as day 22. Overall, osteoconduction and osteointegration mean scores were higher for test implants compared to the controls at 22 and 34 days. Nanoporous hydroxyapatite/sodium titanate bilayer improves the in-vivo osteoconduction and osteointegration. It prevents the delamination during the screwing and it could increase HA-coated dental implant stability without adhesive failures. The combination of thermochemical treatments with dip coating is a low-cost strategy. Copyright © 2017 The Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

THE WORLDWIDE BURDEN OF INFANT MENTAL AND EMOTIONAL DISORDER: REPORT OF THE TASK FORCE OF THE WORLD ASSOCIATION FOR INFANT MENTAL HEALTH.

Science.gov (United States)

Lyons-Ruth, Karlen; Todd Manly, Jody; Von Klitzing, Kai; Tamminen, Tuula; Emde, Robert; Fitzgerald, Hiram; Paul, Campbell; Keren, Miri; Berg, Astrid; Foley, Maree; Watanabe, Hisako

2017-11-01

Children worldwide experience mental and emotional disorders. Mental disorders occurring among young children, especially infants (birth -3 years), often go unrecognized. Prevalence rates are difficult to determine because of lack of awareness and difficulty assessing and diagnosing young children. Existing data, however, suggest that rates of disorders in young children are comparable to those of older children and adolescents (von Klitzing, Dohnert, Kroll, & Grube, ). The lack of widespread recognition of disorders of infancy is particularly concerning due to the unique positioning of infancy as foundational in the developmental process. Both the brain and behavior are in vulnerable states of development across the first 3 years of life, with potential for enduring deviations to occur in response to early trauma and deprivation. Intervention approaches for young children require sensitivity to their developmental needs within their families. The primacy of infancy as a time of unique foundational risks for disorder, the impact of trauma and violence on young children's development, the impact of family disruption on children's attachment, and existing literature on prevalence rates of early disorders are discussed. Finally, global priorities for addressing these disorders of infancy are highlighted to support prevention and intervention actions that may alleviate suffering among our youngest world citizens. © 2017 Michigan Association for Infant Mental Health.

Thermodynamic Considerations of Direct Oxygen Removal from Titanium by Utilizing the Deoxidation Capability of Rare Earth Metals

Science.gov (United States)

Okabe, Toru H.; Zheng, Chenyi; Taninouchi, Yu-ki

2018-06-01

Oxygen removal from metallic Ti is extremely difficult and, currently, there is no commercial process for effectively deoxidizing Ti or its alloys. The oxygen concentration in Ti scraps is normally higher than that in virgin metals such as in Ti sponges produced by the Kroll process. When scraps are remelted with virgin metals for producing primary ingots of Ti or its alloys, the amount of scrap that can be used is limited owing to the accumulation of oxygen impurities. Future demands of an increase in Ti production and of mitigating environmental impacts require that the amount of scrap recycled as a feed material of Ti ingots should also increase. Therefore, it is important to develop methods for removing oxygen directly from Ti scraps. In this study, we evaluated the deoxidation limit for β-Ti using Y or light rare earth metals (La, Ce, Pr, or Nd) as a deoxidant. Thermodynamic considerations suggest that extra-low-oxygen Ti, with an oxygen concentration of 100 mass ppm or less can be obtained using a molten salt equilibrating with rare earth metals. The results presented herein also indicate that methods based on molten salt electrolysis for producing rare earth metals can be utilized for effectively and directly deoxidizing Ti scraps.

Molcas 8: New capabilities for multiconfigurational quantum chemical calculations across the periodic table.

Science.gov (United States)

Aquilante, Francesco; Autschbach, Jochen; Carlson, Rebecca K; Chibotaru, Liviu F; Delcey, Mickaël G; De Vico, Luca; Fdez Galván, Ignacio; Ferré, Nicolas; Frutos, Luis Manuel; Gagliardi, Laura; Garavelli, Marco; Giussani, Angelo; Hoyer, Chad E; Li Manni, Giovanni; Lischka, Hans; Ma, Dongxia; Malmqvist, Per Åke; Müller, Thomas; Nenov, Artur; Olivucci, Massimo; Pedersen, Thomas Bondo; Peng, Daoling; Plasser, Felix; Pritchard, Ben; Reiher, Markus; Rivalta, Ivan; Schapiro, Igor; Segarra-Martí, Javier; Stenrup, Michael; Truhlar, Donald G; Ungur, Liviu; Valentini, Alessio; Vancoillie, Steven; Veryazov, Valera; Vysotskiy, Victor P; Weingart, Oliver; Zapata, Felipe; Lindh, Roland

2016-02-15

In this report, we summarize and describe the recent unique updates and additions to the Molcas quantum chemistry program suite as contained in release version 8. These updates include natural and spin orbitals for studies of magnetic properties, local and linear scaling methods for the Douglas-Kroll-Hess transformation, the generalized active space concept in MCSCF methods, a combination of multiconfigurational wave functions with density functional theory in the MC-PDFT method, additional methods for computation of magnetic properties, methods for diabatization, analytical gradients of state average complete active space SCF in association with density fitting, methods for constrained fragment optimization, large-scale parallel multireference configuration interaction including analytic gradients via the interface to the Columbus package, and approximations of the CASPT2 method to be used for computations of large systems. In addition, the report includes the description of a computational machinery for nonlinear optical spectroscopy through an interface to the QM/MM package Cobramm. Further, a module to run molecular dynamics simulations is added, two surface hopping algorithms are included to enable nonadiabatic calculations, and the DQ method for diabatization is added. Finally, we report on the subject of improvements with respects to alternative file options and parallelization. © 2015 Wiley Periodicals, Inc.

A factorization approach to next-to-leading-power threshold logarithms

Energy Technology Data Exchange (ETDEWEB)

Bonocore, D. [Nikhef,Science Park 105, NL-1098 XG Amsterdam (Netherlands); Laenen, E. [Nikhef,Science Park 105, NL-1098 XG Amsterdam (Netherlands); ITFA, University of Amsterdam,Science Park 904, Amsterdam (Netherlands); ITF, Utrecht University,Leuvenlaan 4, Utrecht (Netherlands); Magnea, L. [Dipartimento di Fisica, Università di Torino and INFN, Sezione di Torino,Via P. Giuria 1, I-10125, Torino (Italy); Melville, S. [School of Physics and Astronomy, University of Glasgow,Glasgow, G12 8QQ (United Kingdom); Vernazza, L. [Higgs Centre for Theoretical Physics, School of Physics and Astronomy, University of Edinburgh,Edinburgh, EH9 3JZ, Scotland (United Kingdom); White, C.D. [School of Physics and Astronomy, University of Glasgow,Glasgow, G12 8QQ (United Kingdom)

2015-06-03

Threshold logarithms become dominant in partonic cross sections when the selected final state forces gluon radiation to be soft or collinear. Such radiation factorizes at the level of scattering amplitudes, and this leads to the resummation of threshold logarithms which appear at leading power in the threshold variable. In this paper, we consider the extension of this factorization to include effects suppressed by a single power of the threshold variable. Building upon the Low-Burnett-Kroll-Del Duca (LBKD) theorem, we propose a decomposition of radiative amplitudes into universal building blocks, which contain all effects ultimately responsible for next-to-leading-power (NLP) threshold logarithms in hadronic cross sections for electroweak annihilation processes. In particular, we provide a NLO evaluation of the radiative jet function, responsible for the interference of next-to-soft and collinear effects in these cross sections. As a test, using our expression for the amplitude, we reproduce all abelian-like NLP threshold logarithms in the NNLO Drell-Yan cross section, including the interplay of real and virtual emissions. Our results are a significant step towards developing a generally applicable resummation formalism for NLP threshold effects, and illustrate the breakdown of next-to-soft theorems for gauge theory amplitudes at loop level.

Do operation management systems pay off?; Lohnt der Einsatz von Betriebsmanagementsystemen?

Energy Technology Data Exchange (ETDEWEB)

Brumme, M.; Fricke, J.

1997-12-31

Operation management systems are an indispensable tool for making those quick decisions so essential to our present level of technical and economic development. The utility of such an investment is evident in the quality of the analyses it permits and the efficiency with which it procures and distributes information. Process analyses require high-performance, practice-oriented systems in order to be delivered quickly, complete, and error-free. The present paper relates examples of projects where plant operators have profited from the procurement of an operation management system. The amortisation periods for these systems ranged between 16 and 29 months. Thus, operation management systems are an attractive option not only for new but also for old plants approaching the end of the lifetime. [Deutsch] Betriebsmanagementsysteme sind in der heutigen Zeit, wo es aus wirtschaftlicher und technischer Sicht auf schnelle Entscheidungen ankommt, ein unverzichtbares Hilfsmittel. Der Nutzen einer derartigen Investition zeigt sich in der Qualitaet der Analysen und in der effektiven Informationsbeschaffung und -verteilung. Die lueckenlose, fehlerfreie und schnelle Analyse von Prozessverlaeufen ist nur mit leistungsstarken und praxisgerechten Systemen moeglich. Die Anschaffung eines Betriebsmanagementsystems hat sich in den beispielhaft beschriebenen Projekten fuer den Anlagenbetreiber gelohnt. Die Amortisationszeiten liegen im Bereich von einem Jahr und 4 Monaten bis 2 Jahren und 5 Monaten. Das macht ein Betriebsmanagementsystem sowohl fuer den Einsatz in Neuanlagen als auch in Altanlagen mit begrenzter Restlebensdauer interessant. (orig./RHM)

Unnessecary nuclear controversy in Iran. Greater chances by an alternative energy strategy

International Nuclear Information System (INIS)

Supersberger, Nikolaus

2008-01-01

Nuclear power is not an indispensable part of Iran's future energy supply. It can be phased out without endangering the reliability of supply. A nuclear controversy is unnecessary from an energy view. The supply sectors for which nuclear power is envisaged can be abandoned without any problem. Also, there is no inherent need for a high consumption growth rate. Enormous amounts of petroleum and natural gas could be saved if Iran were to use the available energy efficiency potential (and also renewable energy sources). Scenario analyses show a very diverse picture of the Iranian power supply system. They show no indication of the extremely urgent need for new power stations that is forecasted by the Iranian government. The number of new power plants that are required is much lower, even if a very conservative business-as-usual energy consumption scenario is assumed. On the other hand, if the current consumption trend continues, Iran's energy future will not be very promising: Already by 2040, Iran will become a net importer of petroleum. The dramatic increase in energy consumption will be made even more problematic by the decreasing petroleum production. Natural gas production can still be enhanced significantly, but consumption in Iran will be growing so rapidly that, after a period of high gas exports, Iran will soon have to import natural gas. (orig./RHM)

Intelligent pricing policy and service marketing. Measures to prevent price cutting wars; Intelligente Preis- und Dienstleistungspolitik. Massnahmen zur Vermeidung von Preiskriegen

Energy Technology Data Exchange (ETDEWEB)

Laker, M.; Herr, S. [Simon-Kucher and Partners, Strategy and Marketing Consultants GmbH, Bonn (Germany)

1998-06-01

Cost-reducing programmes are only the first step in a series of measures to be taken by the power utilities in order to become fit for the free competition markets. A great number of empirical studies on the future power markets do show that for the customers, prices are a priority criterium, but offering competitive prices alone will not suffice to keep one`s competitive edge. The negative consequences of pure price competition (shown by the aviation industry) and the lessons to be learned from ``intelligent`` branches of industry, (eg. mineral oil and cigarettes), who have been clever enough to avoid price cutting wars, demonstrate that there are chances for development also in deregulated power markets. (orig./CB) [Deutsch] Zur Vorbereitung auf die anstehende Liberalisierung muss eine Neuausrichtung der EVU schnellstmoeglich erfolgen. Reine Kostensenkungsprogramme sind dabei nur der erste Schritt, um fuer den Wettbewerb fit zu werden. Hierzu zaehlt die strategische und marketingorientierte Ausrichtung des Unternehmens auf den Wettbewerb. Zahlreiche empirische Studien zum EVU-Markt kommen zwar zu dem Ergebnis, dass aus der Sicht des Kunden der Preis einen hohen Stellenwert einnimmt. Ein wettbewerbsorientierter Preis ist notwendig, reicht aber zum erfolgreichen Ueberleben im Wettbewerb alleine nur bei ueberlegener Kostenfuehrerschaft aus. Die negativen Auswirkungen eines reinen Preiswettbewerbs (Luftfahrt) sowie die Lehren aus `intelligenten` Branchen (Mineraloel-, Zigarettenindustrie), die dies vermeiden, zeigen die vielfaeltigen Entwicklungsmoeglichkeiten auch fuer den Energie-Wettbewerbsmarkt auf. (orig./RHM)

Fit for competition with ``EVS `99``; Mit ``EVS `99`` fit fuer den Wettbewerb

Energy Technology Data Exchange (ETDEWEB)

Klawunn, K.H.; Wamhof, F. [Energieversorgung Suedsachsen AG, Chemnitz (Germany)

1998-05-01

The Energieversorgung Suedsachsen AG (EVS AG) located in Chemnitz faces up to the challenges of the competitive energy market. The company launched the project ``EVS `99`` in order to achieve the essential strategic goals: increase customer loyalty, concentrate on the core business, open up new operating areas, improve the core competences. This comprehensive business re-engineering project is intended to realise by the end of the business year 1997/98 an optimisation of all essential business processes, which are to focus on customer needs, establishment of an efficient, customer-oriented organisation in line with the strategy, and design of the required management and control systems. The technical and communication systems will be based on the SAP R/3 software in order to fully exploit the optimisation potentials. (orig./CB) [Deutsch] Die Energieversorgung Suedsachsen AG (EVS AG) in Chemnitz stellt sich aktiv den Herausforderungen des Wettbewerbs. Um die strategischen Unternehmensziele Erhoehung der Kundenbindung, Konzentration auf das Kerngeschaeft, Erschliessung neuer Geschaeftsfelder und Verbesserung der Kernkompetenzen zu erreichen, wurde das Projekt `EVS `99` initiiert. Durch dieses umfassende Business-Reengineering-Projekt wird bis Ende des Geschaeftsjahres 1997/98 die Optimierung aller wesentlichen Geschaeftsprozesse und deren Ausrichtung an den Kundenanforderungen, der Aufbau einer strategiekonformen, effizienten, kundenorientierten Organisation und die Gesaltung anforderungsgerechter Fuehrungs- und Steuerungssysteme realisiert. Begleitend wird die Software SAP R/3 im Unternehmen eingefuehrt, um umfassend, d.h. bereichsuebergreifend, alle Optimierungspotentiale zu nutzen. (orig./RHM)

Description of the initiation and progress of cracks for hot cracks in temperature resistant 1% CrMoV castings under creep or fatigue stress

International Nuclear Information System (INIS)

Bareiss, J.; Maile, K.; Berger, C.; Mayer, K.H.; Weiss, M.

1994-01-01

The results available so far have shown that under vibration stress at room temperature and at 530 C, the simplified equations of fracture mechanics are sufficient (in spite of the complicated fault geometries), in order to conservatively describe the behaviour of fault positions (open or partly-healed hot cracks) with regard to their crack initiation behaviour if combined with the findings US test technique. Here the sample castings which in the initial state showed fault indications of US type EET near the surface, tend to earlier initiation of a crack compared to lower fault positions of the samples. Internal fault positions (partially healed hot cracks) often only showed local cracks (trans-crystalline deformation cracks) within the fault area with an order of magnitude of about 10-50 μm, in spite of exceeding the threshold value Δ Ko. The comparison of the crack propagation behaviour of the sample castings, determined via the potential sensor method on medium lengths of fault with the results of crack growth of fracture mechanics samples in the da/dN- Δ K diagram showed for the evaluated sample castings with a relatively great initial depth or length of fault that the upper scatter band limit of the Paris Law determined for the material can be used to estimate the fault position behaviour. (orig./RHM) [de

Gaussian basis sets for use in correlated molecular calculations. XI. Pseudopotential-based and all-electron relativistic basis sets for alkali metal (K-Fr) and alkaline earth (Ca-Ra) elements

Science.gov (United States)

Hill, J. Grant; Peterson, Kirk A.

2017-12-01

New correlation consistent basis sets based on pseudopotential (PP) Hamiltonians have been developed from double- to quintuple-zeta quality for the late alkali (K-Fr) and alkaline earth (Ca-Ra) metals. These are accompanied by new all-electron basis sets of double- to quadruple-zeta quality that have been contracted for use with both Douglas-Kroll-Hess (DKH) and eXact 2-Component (X2C) scalar relativistic Hamiltonians. Sets for valence correlation (ms), cc-pVnZ-PP and cc-pVnZ-(DK,DK3/X2C), in addition to outer-core correlation [valence + (m-1)sp], cc-p(w)CVnZ-PP and cc-pwCVnZ-(DK,DK3/X2C), are reported. The -PP sets have been developed for use with small-core PPs [I. S. Lim et al., J. Chem. Phys. 122, 104103 (2005) and I. S. Lim et al., J. Chem. Phys. 124, 034107 (2006)], while the all-electron sets utilized second-order DKH Hamiltonians for 4s and 5s elements and third-order DKH for 6s and 7s. The accuracy of the basis sets is assessed through benchmark calculations at the coupled-cluster level of theory for both atomic and molecular properties. Not surprisingly, it is found that outer-core correlation is vital for accurate calculation of the thermodynamic and spectroscopic properties of diatomic molecules containing these elements.

Gaussian basis sets for use in correlated molecular calculations. XI. Pseudopotential-based and all-electron relativistic basis sets for alkali metal (K-Fr) and alkaline earth (Ca-Ra) elements.

Science.gov (United States)

Hill, J Grant; Peterson, Kirk A

2017-12-28

New correlation consistent basis sets based on pseudopotential (PP) Hamiltonians have been developed from double- to quintuple-zeta quality for the late alkali (K-Fr) and alkaline earth (Ca-Ra) metals. These are accompanied by new all-electron basis sets of double- to quadruple-zeta quality that have been contracted for use with both Douglas-Kroll-Hess (DKH) and eXact 2-Component (X2C) scalar relativistic Hamiltonians. Sets for valence correlation (ms), cc-pVnZ-PP and cc-pVnZ-(DK,DK3/X2C), in addition to outer-core correlation [valence + (m-1)sp], cc-p(w)CVnZ-PP and cc-pwCVnZ-(DK,DK3/X2C), are reported. The -PP sets have been developed for use with small-core PPs [I. S. Lim et al., J. Chem. Phys. 122, 104103 (2005) and I. S. Lim et al., J. Chem. Phys. 124, 034107 (2006)], while the all-electron sets utilized second-order DKH Hamiltonians for 4s and 5s elements and third-order DKH for 6s and 7s. The accuracy of the basis sets is assessed through benchmark calculations at the coupled-cluster level of theory for both atomic and molecular properties. Not surprisingly, it is found that outer-core correlation is vital for accurate calculation of the thermodynamic and spectroscopic properties of diatomic molecules containing these elements.

Ab initio study of spectroscopic properties of bimetallic molecules MeB (where Me=Li, Na, K, Br, Cs, Fr) using CCSD(T) and MRCI methods

International Nuclear Information System (INIS)

Cukovicova, M.; Cernusak, I.

2010-01-01

For our study we have chosen a series of diatomic molecules MeB (where Me = Li, Na, K, Rb, Cs, Fr). These molecules present experimentally unknown species, hence we were motivated to predict theoretically potential energy curves, equilibrium bond lengths, harmonic frequencies, constants of anharmonicity, dipole moments and dissociation energies for the ground and low-lying excited states using high level ab initio techniques. Based on previous state averaged MRCI calculations in ANO-S basis set of NaB and KB molecules, we have focused on four lowest-lying electronic states, ground state 3Π and excited states 1Σ+, 1Π and 3Σ+. All four states dissociate to the atoms in ground states 2P1/2(B) and 2S1/2(Me). 3Π, 1Σ+, 1Π and 3Σ+ electronic states we investigated employing CCSD(T) method using relativistic ANO-RCC basis set. Our calculations include scalar relativistic effects via the second order one-component (spin-free) Douglas-Kroll-Hess Hamiltonian. Relativistic effects become remarkable in the case of heavy atoms, hence properties of CsB and FrB molecules may differ from trend of properties in row from LiB to FrB. Spectroscopic properties of particular state were obtained from the analysis of the potential energy curves using VIBROT and DUNHAM programs.

Inclusive prompt photon production in electron-nucleus scattering at small x

Science.gov (United States)

Roy, Kaushik; Venugopalan, Raju

2018-05-01

We compute the differential cross-section for inclusive prompt photon production in deeply inelastic scattering (DIS) of electrons on nuclei at small x in the framework of the Color Glass Condensate (CGC) effective theory. The leading order (LO) computation in this framework resums leading logarithms in x as well as power corrections to all orders in Q s, A 2 / Q 2, where Q s, A ( x) is the nuclear saturation scale. This LO result is proportional to universal dipole and quadrupole Wilson line correlators in the nucleus. In the soft photon limit, the Low-Burnett-Kroll theorem allows us to recover existing results on inclusive DIS dijet production. The k ⊥ and collinearly factorized expressions for prompt photon production in DIS are also recovered in a leading twist approximation to our result. In the latter case, our result corresponds to the dominant next-to-leading order (NLO) perturbative QCD contribution at small x. We next discuss the computation of the NLO corrections to inclusive prompt photon production in the CGC framework. In particular, we emphasize the advantages for higher order computations in inclusive photon production, and for fully inclusive DIS, arising from the simple momentum space structure of the dressed quark and gluon "shock wave" propagators in the "wrong" light cone gauge A - = 0 for a nucleus moving with P N + → ∞.

Predicting Near Edge X-ray Absorption Spectra with the Spin-Free Exact-Two-Component Hamiltonian and Orthogonality Constrained Density Functional Theory.

Science.gov (United States)

Verma, Prakash; Derricotte, Wallace D; Evangelista, Francesco A

2016-01-12

Orthogonality constrained density functional theory (OCDFT) provides near-edge X-ray absorption (NEXAS) spectra of first-row elements within one electronvolt from experimental values. However, with increasing atomic number, scalar relativistic effects become the dominant source of error in a nonrelativistic OCDFT treatment of core-valence excitations. In this work we report a novel implementation of the spin-free exact-two-component (X2C) one-electron treatment of scalar relativistic effects and its combination with a recently developed OCDFT approach to compute a manifold of core-valence excited states. The inclusion of scalar relativistic effects in OCDFT reduces the mean absolute error of second-row elements core-valence excitations from 10.3 to 2.3 eV. For all the excitations considered, the results from X2C calculations are also found to be in excellent agreement with those from low-order spin-free Douglas-Kroll-Hess relativistic Hamiltonians. The X2C-OCDFT NEXAS spectra of three organotitanium complexes (TiCl4, TiCpCl3, TiCp2Cl2) are in very good agreement with unshifted experimental results and show a maximum absolute error of 5-6 eV. In addition, a decomposition of the total transition dipole moment into partial atomic contributions is proposed and applied to analyze the nature of the Ti pre-edge transitions in the three organotitanium complexes.

Operation management systems in the energy economy in `97; Betriebsmanagement-Systeme in der Energiewirtschaft `97

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-12-31

VDI Report 1310 contains the lectures held at the congress on ``Operation management systems in the energy economy `97`` in Wuerzburg on 12 and 13 March 1997. Operation management systems, beside fulfilling several other functions, work with the input they receive from plant management systems. They analyse and condense characteristic values, facilitate optimal utilisation of all resources, and supply in-depth information for the preparation of the management`s strategic decisions. This information concerns the analysis of plant characteristics, monitoring of the service life of heavily loaded plant components, preparation of balances, planning of maintenance and repair measures, purchase, and materials management. The purpose of the congress was to point out developments and present and discuss practical examples from the following areas: power plant, energy network, energy supply for municipalities and industry. [Deutsch] Der VDI-Bericht 1310 enthaelt die Vortraege der gleichnamigen Tagung, die am 12. und 13. Maerz 1997 in Wuerzburg stattfand. Betriebsfuehrungssysteme basieren auf dem Input von Anlagenfuehrungssystemen und uebernehmen weitergehende Aufgaben. Sie analysieren und verdichten Kennwerte, ermoeglichen den optimalen Einsatz aller Betriebsmittel und stellen vertiefte Informationen zur Vorbereitung strategischer Entscheidungen fuer das Management zur Verfuegung. Dabei handelt es sich um die Analyse von Anlagenkennwerten, die Lebensdauerueberwachung hochbelasteter Anlagenteile, das Erstellen von Bilanzen, die Planung von Wartungs- und Instandhaltungsmassnahmen bis hin zum Einkauf und der Materialwirtschaft. Aufgabe der Tagung war es, Entwicklungen aufzuzeigen und praktische Beispiele aus den Sektoren Kraftwerk, Energienetze, kommunale Versorgung und Industrie darzustellen und zu diskutieren. (orig./RHM)

The Three Gorges Project of China. An engineering project of the century, or megalomania?; Chinas ``Drei-Schluchten-Project``. Jahrhundertwerk oder Groessenwahn?

Energy Technology Data Exchange (ETDEWEB)

Sauer, H.D.

1998-03-01

The Three Gorges Project on the Yangtse River is one of the biggest hydraulic engineering projects ever. Its objectives are threefold: Improve flood control for a region with a population of several millions of people, generate power of an order of magnitude comparable to the output of ten nuclear power plants, and improve the navigability of China`s most important waterway. Just as any other big, international hydraulic engineering project, this one, too, has raised a storm of protest from opponents. Primarily the re-settlement of 1.3 million of people and aspects of the structural stability of the dam and related hazards are issues of controversy. In the eyes of the author of this article, opponents in the western hemisphere are drawing a far too gloomy picture in their rejection of the project. (orig./CB) [Deutsch] Das `Drei-Schluchten-Projekt` am Jangtse ist eines der anspruchsvollsten Wasserbauvorhaben, die je in Angriff genommen wurden. Es soll drei Zwecke erfuellen: Verbesserten Hochwasserschutz fuer Millionen von Menschen, Stromerzeugung in der Groessenordnung von zehn Kernkraftwerken sowie Erleichterung der Schiffahrt auf Chinas wichtigster Wasserstrasse. Wie wohl jedes internationale Wasserbauprojekt hat auch dieses gewaltige Vorhaben Protest bei Gegnern weltweit hervorgerufen. Insbesondere die erforderliche Umsiedlung von 1,3 Millionen Menschen und die Frage der Staumauersicherheit werden heftigst kritisiert bzw. angezweifelt. Mit der Verteufelung des Projektes schiessen die Anti-Staudamm-Gruppen aus dem Westen aber weit uebers Ziel hinaus. (orig./RHM)

New energy conversion processes and neglected auxiliary systems - a treasure trove for energy service providers; Neue Techniken und vernachlaessigte Nebenanlagen - eine Fundgrube fuer Energiedienstleister

Energy Technology Data Exchange (ETDEWEB)

Jochem, E.

1998-12-31

The paper shows that apart from the risks, the deregulation of the energy sector also offered new chances, which recently materialized in three emerging independent trends, initiating innovative approaches for energy conversion and applications and demand for new knowledge-based, near-production energy services as a new field for engineers: Providers of energy efficiency-related technology widen their capabilities by adding the new business segment of energy service marketing. Industrial energy users more strongly consider outsourcing of energy conversion systems and the relevant contracting schemes as an option for reducing energy costs. Public enterprise as energy users started following this trend, all the more as insufficient financial resources do not permit them to reinvest. The paper discusses the conversion processes which currently open up promising chances for energy service producers. (orig./CB) [Deutsch] Neben Gefahren, die inhaerentes Merkmal der Liberalisierung sind, zeichnen sich drei unabhaengige Entwicklungen ab, die innovative Initiativen in der Energiewandlung und -nutzung staerken und wissensintensive produktionsnahe Dienstleistungen als zentrale Aufgabe fuer den Ingenieur initieren: - Die Energieeffizienz-Technologieanbieter nehmen die Energiedienstleistungen in ihre Angebotspalette auf. - Die betrieblichen Energieanwender beginnen zunehmend, ueber das Outsourcing energiewandelnder Anlagen Energiekosten zu senken. - Die oeffentliche Hand als Energieanwender beginnt aehnlich zu denken, zumal sie infolge der hohen Verschuldung unzureichende finanzielle Mittel fuer Reinvestitionen hat. Hierueber sei kurz berichtet, bevor auf die Techniken eingegangen wird, die sich besonders aus heutiger Sicht fuer Energiedienstleister eignen. (orig./RHM)

Rilem TC 203-RHM. Repair mortars for historic masonry. The role of mortar in masonry: an introduction to requirements for the design of repair mortars

NARCIS (Netherlands)

Hees, R.P.J. van; Groot, C.; Balen, K. van; Bicer-Simsir, B.; Binda, L.; Elsen, J.; Konow, T. von; Lindqvist, J.E.; Maurenbrecher, P.; Papayanni, I.; Subercaseaux, M.; Tedeschi, C.; Toumbakari, E.E.; Thompson, M.

2012-01-01

Mortar has been in use for many thousands of years and is integral to most masonry construction. Its use is widespread in every culture where masonry is constructed. It is present in the majority of the global built cultural heritage, and is therefore a major consideration in building conservation.

RILEM TC 203-RHM: Repair mortars for historic masonry The role of mortar in masonry: an introduction to requirements for the design of repair mortars

Czech Academy of Sciences Publication Activity Database

Groot, C.; van Balen, K.; Bicer-Simsir, B.; Binda, L.; Elsen, J.; van Hees, R.; von Konow, T.; Lindqvist, J.; Mauerbrecher, P.; Papayanni, I.; Subercaseaux, M.; Tedeschi, C.; Toumbakari, E.; Thompson, M.; Válek, Jan; Veiga, R.

2012-01-01

Roč. 45, č. 9 (2012), s. 1287-1294 ISSN 1359-5997 Institutional support: RVO:68378297 Keywords : mortar * classification * requirements Subject RIV: JN - Civil Engineering Impact factor: 1.184, year: 2012

Density functional studies on the exchange interaction of a dinuclear Gd(iii)-Cu(ii) complex: method assessment, magnetic coupling mechanism and magneto-structural correlations.

Science.gov (United States)

Rajaraman, Gopalan; Totti, Federico; Bencini, Alessandro; Caneschi, Andrea; Sessoli, Roberta; Gatteschi, Dante

2009-05-07

Density functional calculations have been performed on a [Gd(iii)Cu(ii)] complex [L(1)CuGd(O(2)CCF(3))(3)(C(2)H(5)OH)(2)] () (where L(1) is N,N'-bis(3-ethoxy-salicylidene)-1,2-diamino-2-methylpropanato) with an aim of assessing a suitable functional within the DFT formalism to understand the mechanism of magnetic coupling and also to develop magneto-structural correlations. Encouraging results have been obtained in our studies where the application of B3LYP on the crystal structure of yields a ferromagnetic J value of -5.8 cm(-1) which is in excellent agreement with the experimental value of -4.42 cm(-1) (H = JS(Gd).S(Cu)). After testing varieties of functional for the method assessment we recommend the use of B3LYP with a combination of an effective core potential basis set. For all electron basis sets the relativistic effects should be incorporated either via the Douglas-Kroll-Hess (DKH) or zeroth-order regular approximation (ZORA) methods. A breakdown approach has been adopted where the calculations on several model complexes of have been performed. Their wave functions have been analysed thereafter (MO and NBO analysis) in order to gain some insight into the coupling mechanism. The results suggest, unambiguously, that the empty Gd(iii) 5d orbitals have a prominent role on the magnetic coupling. These 5d orbitals gain partial occupancy via Cu(ii) charge transfer as well as from the Gd(iii) 4f orbitals. A competing 4f-3d interaction associated with the symmetry of the complex has also been observed. The general mechanism hence incorporates both contributions and sets forth rather a prevailing mechanism for the 3d-4f coupling. The magneto-structural correlations reveal that there is no unique parameter which the J values are strongly correlated with, but an exponential relation to the J value found for the O-Cu-O-Gd dihedral angle parameter is the most credible correlation.

DNK Energy Day '98. Energy and environment as subjects in the dialog between politics, economy and the scientific community; DNK Energietag '98. Energie und Umwelt im Dialog zwischen Politik, Wirtschaft und Wissenschaft

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-07-01

This fifth one-day energy forum of the DNK held in Bonn on 26 November 1998 once again gathered many representatives of industry, science and research, and the political arena. The date of the meeting in mid-November was well-chosen, as it offered the opportunity to discuss the outcome of the 17th World Energy Congress held two months ago in Houston/USA, and to communicate on expectations in Germany linked to the future energy policy of the new coalition in power. The general theme of the forum, 'Energy and environment as issues of a dialogue of politicians, industry and science' thus fits in well with the global energy issues. The contributions to the panel discussion with the concluding summary of Dr. Ott as well as the lectures presented at the meeting are reproduced or this conference report from the manuscripts and the minutes. (orig./CB) [German] Der 5. Energietag des DNK in Bonn am 26. November 1998 hat erneut zahlreiche Repraesentanten aus Wirtschaft, Wissenschaft und Politik zusammengefuehrt. Der Zeitpunkt Mitte November 1998 bot die Gelegenheit, einerseits die Ergebnisse des 17. Kongresses des Weltenergierates, der gerade 2 Monate zuvor in Houston stattfand, zu erlaeutern und zum anderen, ueber die energiepolitischen Erwartungen an die neue Bundesregierung und deren Vorstellungen zur kuenftigen Energiepolitik zu diskutieren. Das Generalthema des Forums 'Energie und Umwelt im Dialog zwischen Politik, Wirtschaft und Wissenschaft' hatte damit aktuellen Bezug. Die Beitraege der Podiumsdiskussion mit den Schlussbemerkungen von Dr. Ott sind wie die Vortraege weitgehend im Originalwortlaut wiedergegeben. Sie werden im vorliegenden Heft dokumentiert. (orig./RHM)

Customer-oriented flexitime schemes; Kundenorientierte Arbeitszeitflexibilisierung

Energy Technology Data Exchange (ETDEWEB)

Wiedemann, E. [Lech-Elektrizitaetswerke (LEW) AG, Augsburg (Germany)

1998-05-01

In a competitive market, only those enterprises will persist that offer not only high-quality products but quality in a very comprehensive sense as well. Total customer care is the keyword in this context and is indispensable when it comes to establishing and maintaining brand perception and loyalty. The features and benefits of products, activities and services have to be tailored to the individual needs of the target group and the individual customer. In addition, the price/performance ratio of products and services must be carefully designed so as to be acceptable to a large variety of customers. This applies both to the ``hardware`` such as product quality and efficiency, and the product-related activities such as product information and consultancy, customer service organization, reachability of service or call centers, and handling of complaints and claims. (orig./CB) [Deutsch] Im Wettbewerb kann heute nur bestehen, wer ueber das Produkt hinaus Qualitaet in einem sehr umfassenden Sinne liefert. Eine starke Orientierung am Kundeninteresse (neudeutsch: Total Customer Care) ist eigentlich selbstverstaendlich, wenn es um Aufbau, Ausbau und Pflege von Markenbeziehungen geht. Die Eigenschaften und der Nutzen von Marktleistungen muessen den individuellen Beduerfnissen und Erwartungen der Zielgruppe oder einer Einzelperson entsprechen. Darueber hinaus ist Voraussetzung, dass die angebotenen Leistungen aus der subjektiven Sicht der Kunden in einem fuer sie akzeptablen Preis-Leistungs-Verhaeltnis stehen. Dies betrifft nicht allein die `harten Fakten` wie Qualitaet oder Funktion. Es gilt auch fuer alle Leistungen rund um das Produkt, insbesondere Beratung, Erreichbarkeit, Kundenservice oder Reklamationsbearbeitung. (orig./RHM)

Model-model Perencanaan Strategik

OpenAIRE

Amirin, Tatang M

2005-01-01

The process of strategic planning, used to be called as long-term planning, consists of several components, including strategic analysis, setting strategic direction (covering of mission, vision, and values), and action planning. Many writers develop models representing the steps of the strategic planning process, i.e. basic planning model, problem-based planning model, scenario model, and organic or self-organizing model.

Model-to-model interface for multiscale materials modeling

Energy Technology Data Exchange (ETDEWEB)

Antonelli, Perry Edward [Iowa State Univ., Ames, IA (United States)

2017-12-17

A low-level model-to-model interface is presented that will enable independent models to be linked into an integrated system of models. The interface is based on a standard set of functions that contain appropriate export and import schemas that enable models to be linked with no changes to the models themselves. These ideas are presented in the context of a specific multiscale material problem that couples atomistic-based molecular dynamics calculations to continuum calculations of fluid ow. These simulations will be used to examine the influence of interactions of the fluid with an adjacent solid on the fluid ow. The interface will also be examined by adding it to an already existing modeling code, Large-scale Atomic/Molecular Massively Parallel Simulator (LAMMPS) and comparing it with our own molecular dynamics code.

Models and role models.

Science.gov (United States)

ten Cate, Jacob M

2015-01-01

Developing experimental models to understand dental caries has been the theme in our research group. Our first, the pH-cycling model, was developed to investigate the chemical reactions in enamel or dentine, which lead to dental caries. It aimed to leverage our understanding of the fluoride mode of action and was also utilized for the formulation of oral care products. In addition, we made use of intra-oral (in situ) models to study other features of the oral environment that drive the de/remineralization balance in individual patients. This model addressed basic questions, such as how enamel and dentine are affected by challenges in the oral cavity, as well as practical issues related to fluoride toothpaste efficacy. The observation that perhaps fluoride is not sufficiently potent to reduce dental caries in the present-day society triggered us to expand our knowledge in the bacterial aetiology of dental caries. For this we developed the Amsterdam Active Attachment biofilm model. Different from studies on planktonic ('single') bacteria, this biofilm model captures bacteria in a habitat similar to dental plaque. With data from the combination of these models, it should be possible to study separate processes which together may lead to dental caries. Also products and novel agents could be evaluated that interfere with either of the processes. Having these separate models in place, a suggestion is made to design computer models to encompass the available information. Models but also role models are of the utmost importance in bringing and guiding research and researchers. 2015 S. Karger AG, Basel

Hydrological models are mediating models

Science.gov (United States)

Babel, L. V.; Karssenberg, D.

2013-08-01

Despite the increasing role of models in hydrological research and decision-making processes, only few accounts of the nature and function of models exist in hydrology. Earlier considerations have traditionally been conducted while making a clear distinction between physically-based and conceptual models. A new philosophical account, primarily based on the fields of physics and economics, transcends classes of models and scientific disciplines by considering models as "mediators" between theory and observations. The core of this approach lies in identifying models as (1) being only partially dependent on theory and observations, (2) integrating non-deductive elements in their construction, and (3) carrying the role of instruments of scientific enquiry about both theory and the world. The applicability of this approach to hydrology is evaluated in the present article. Three widely used hydrological models, each showing a different degree of apparent physicality, are confronted to the main characteristics of the "mediating models" concept. We argue that irrespective of their kind, hydrological models depend on both theory and observations, rather than merely on one of these two domains. Their construction is additionally involving a large number of miscellaneous, external ingredients, such as past experiences, model objectives, knowledge and preferences of the modeller, as well as hardware and software resources. We show that hydrological models convey the role of instruments in scientific practice by mediating between theory and the world. It results from these considerations that the traditional distinction between physically-based and conceptual models is necessarily too simplistic and refers at best to the stage at which theory and observations are steering model construction. The large variety of ingredients involved in model construction would deserve closer attention, for being rarely explicitly presented in peer-reviewed literature. We believe that devoting

Modeling Documents with Event Model

Directory of Open Access Journals (Sweden)

Longhui Wang

2015-08-01

Full Text Available Currently deep learning has made great breakthroughs in visual and speech processing, mainly because it draws lessons from the hierarchical mode that brain deals with images and speech. In the field of NLP, a topic model is one of the important ways for modeling documents. Topic models are built on a generative model that clearly does not match the way humans write. In this paper, we propose Event Model, which is unsupervised and based on the language processing mechanism of neurolinguistics, to model documents. In Event Model, documents are descriptions of concrete or abstract events seen, heard, or sensed by people and words are objects in the events. Event Model has two stages: word learning and dimensionality reduction. Word learning is to learn semantics of words based on deep learning. Dimensionality reduction is the process that representing a document as a low dimensional vector by a linear mode that is completely different from topic models. Event Model achieves state-of-the-art results on document retrieval tasks.

Semiparametric modeling: Correcting low-dimensional model error in parametric models

International Nuclear Information System (INIS)

Berry, Tyrus; Harlim, John

2016-01-01

In this paper, a semiparametric modeling approach is introduced as a paradigm for addressing model error arising from unresolved physical phenomena. Our approach compensates for model error by learning an auxiliary dynamical model for the unknown parameters. Practically, the proposed approach consists of the following steps. Given a physics-based model and a noisy data set of historical observations, a Bayesian filtering algorithm is used to extract a time-series of the parameter values. Subsequently, the diffusion forecast algorithm is applied to the retrieved time-series in order to construct the auxiliary model for the time evolving parameters. The semiparametric forecasting algorithm consists of integrating the existing physics-based model with an ensemble of parameters sampled from the probability density function of the diffusion forecast. To specify initial conditions for the diffusion forecast, a Bayesian semiparametric filtering method that extends the Kalman-based filtering framework is introduced. In difficult test examples, which introduce chaotically and stochastically evolving hidden parameters into the Lorenz-96 model, we show that our approach can effectively compensate for model error, with forecasting skill comparable to that of the perfect model.

Vector models and generalized SYK models

Energy Technology Data Exchange (ETDEWEB)

Peng, Cheng [Department of Physics, Brown University,Providence RI 02912 (United States)

2017-05-23

We consider the relation between SYK-like models and vector models by studying a toy model where a tensor field is coupled with a vector field. By integrating out the tensor field, the toy model reduces to the Gross-Neveu model in 1 dimension. On the other hand, a certain perturbation can be turned on and the toy model flows to an SYK-like model at low energy. A chaotic-nonchaotic phase transition occurs as the sign of the perturbation is altered. We further study similar models that possess chaos and enhanced reparameterization symmetries.

[Bone remodeling and modeling/mini-modeling.

Science.gov (United States)

Hasegawa, Tomoka; Amizuka, Norio

Modeling, adapting structures to loading by changing bone size and shapes, often takes place in bone of the fetal and developmental stages, while bone remodeling-replacement of old bone into new bone-is predominant in the adult stage. Modeling can be divided into macro-modeling(macroscopic modeling)and mini-modeling(microscopic modeling). In the cellular process of mini-modeling, unlike bone remodeling, bone lining cells, i.e., resting flattened osteoblasts covering bone surfaces will become active form of osteoblasts, and then, deposit new bone onto the old bone without mediating osteoclastic bone resorption. Among the drugs for osteoporotic treatment, eldecalcitol(a vitamin D3 analog)and teriparatide(human PTH[1-34])could show mini-modeling based bone formation. Histologically, mature, active form of osteoblasts are localized on the new bone induced by mini-modeling, however, only a few cell layer of preosteoblasts are formed over the newly-formed bone, and accordingly, few osteoclasts are present in the region of mini-modeling. In this review, histological characteristics of bone remodeling and modeling including mini-modeling will be introduced.

Multireference configuration interaction study on spectroscopic properties of low-lying electronic states of As2 molecule

International Nuclear Information System (INIS)

Wang Jie-Min; Liu Qiang

2013-01-01

The potential energy curves (PECs) of four electronic states (X 1 Σ g + , e 3 Δ u , a 3 Σ u − , and d 3 Π g ) of an As 2 molecule are investigated employing the complete active space self-consistent field (CASSCF) method followed by the valence internally contracted multireference configuration interaction (MRCI) approach in conjunction with the correlation-consistent aug-cc-pV5Z basis set. The effect on PECs by the relativistic correction is taken into account. The way to consider the relativistic correction is to employ the second-order Douglas-Kroll Hamiltonian approximation. The correction is made at the level of a cc-pV5Z basis set. The PECs of the electronic states involved are extrapolated to the complete basis set limit. With the PECs, the spectroscopic parameters (T e , R e , ω e , ω e x e , ω e y e , α e , β e , γ e , and B e ) of these electronic states are determined and compared in detail with those reported in the literature. Excellent agreement is found between the present results and the experimental data. The first 40 vibrational states are studied for each electronic state when the rotational quantum number J equals zero. In addition, the vibrational levels, inertial rotation and centrifugal distortion constants of d 3 Π g electronic state are reported which are in excellent agreement with the available measurements. Comparison with the experimental data shows that the present results are both reliable and accurate. (atomic and molecular physics)

Security practices and regulatory compliance in the healthcare industry.

Science.gov (United States)

Kwon, Juhee; Johnson, M Eric

2013-01-01

Securing protected health information is a critical responsibility of every healthcare organization. We explore information security practices and identify practice patterns that are associated with improved regulatory compliance. We employed Ward's cluster analysis using minimum variance based on the adoption of security practices. Variance between organizations was measured using dichotomous data indicating the presence or absence of each security practice. Using t tests, we identified the relationships between the clusters of security practices and their regulatory compliance. We utilized the results from the Kroll/Healthcare Information and Management Systems Society telephone-based survey of 250 US healthcare organizations including adoption status of security practices, breach incidents, and perceived compliance levels on Health Information Technology for Economic and Clinical Health, Health Insurance Portability and Accountability Act, Red Flags rules, Centers for Medicare and Medicaid Services, and state laws governing patient information security. Our analysis identified three clusters (which we call leaders, followers, and laggers) based on the variance of security practice patterns. The clusters have significant differences among non-technical practices rather than technical practices, and the highest level of compliance was associated with hospitals that employed a balanced approach between technical and non-technical practices (or between one-off and cultural practices). Hospitals in the highest level of compliance were significantly managing third parties' breaches and training. Audit practices were important to those who scored in the middle of the pack on compliance. Our results provide security practice benchmarks for healthcare administrators and can help policy makers in developing strategic and practical guidelines for practice adoption.

Recall and response time norms for English-Swahili word pairs and facts about Kenya.

Science.gov (United States)

Bangert, Ashley S; Heydarian, Nazanin M

2017-02-01

In the vast literature exploring learning, many studies have used paired-associate stimuli, despite the fact that real-world learning involves many different types of information. One of the most popular materials used in studies of learning has been a set of Swahili-English word pairs for which Nelson and Dunlosky (Memory 2; 325-335, 1994) published recall norms two decades ago. These norms involved use of the Swahili words as cues to facilitate recall of the English translation. It is unclear whether cueing in the opposite direction (from English to Swahili) would lead to symmetric recall performance. Bilingual research has suggested that translation in these two different directions involves asymmetric links that may differentially impact recall performance, depending on which language is used as the cue (Kroll & Stewart, Journal of Memory and Language 33; 149-174,1994). Moreover, the norms for these and many other learning stimuli have typically been gathered from college students. In the present study, we report recall accuracy and response time norms for Swahili words when they are cued by their English translations. We also report norms for a companion set of fact stimuli that may be used along with the Swahili-English word pairs to assess learning on a broader scale across different stimulus materials. Data were collected using Amazon's Mechanical Turk to establish a sample that was diverse in both age and ethnicity. These different, but related, stimulus sets will be applicable to studies of learning, metacognition, and memory in diverse samples.

Recent development of relativistic molecular theory

International Nuclear Information System (INIS)

Takahito, Nakajima; Kimihiko, Hirao

2005-01-01

Today it is common knowledge that relativistic effects are important in the heavy-element chemistry. The continuing development of the relativistic molecular theory is opening up rows of the periodic table that are impossible to treat with the non-relativistic approach. The most straightforward way to treat relativistic effects on heavy-element systems is to use the four-component Dirac-Hartree-Fock approach and its electron-correlation methods based on the Dirac-Coulomb(-Breit) Hamiltonian. The Dirac-Hartree-Fock (DHF) or Dirac-Kohn-Sham (DKS) equation with the four-component spinors composed of the large- and small-components demands severe computational efforts to solve, and its applications to molecules including heavy elements have been limited to small- to medium-size systems. Recently, we have developed a very efficient algorithm for the four-component DHF and DKS approaches. As an alternative approach, several quasi-relativistic approximations have also been proposed instead of explicitly solving the four-component relativistic equation. We have developed the relativistic elimination of small components (RESC) and higher-order Douglas-Kroll (DK) Hamiltonians within the framework of the two-component quasi-relativistic approach. The developing four-component relativistic and approximate quasi-relativistic methods have been implemented into a program suite named REL4D. In this article, we will introduce the efficient relativistic molecular theories to treat heavy-atomic molecular systems accurately via the four-component relativistic and the two-component quasi-relativistic approaches. We will also show several chemical applications including heavy-element systems with our relativistic molecular approaches. (author)

ROCK PROPERTIES MODEL ANALYSIS MODEL REPORT

International Nuclear Information System (INIS)

Clinton Lum

2002-01-01

The purpose of this Analysis and Model Report (AMR) is to document Rock Properties Model (RPM) 3.1 with regard to input data, model methods, assumptions, uncertainties and limitations of model results, and qualification status of the model. The report also documents the differences between the current and previous versions and validation of the model. The rock properties models are intended principally for use as input to numerical physical-process modeling, such as of ground-water flow and/or radionuclide transport. The constraints, caveats, and limitations associated with this model are discussed in the appropriate text sections that follow. This work was conducted in accordance with the following planning documents: WA-0344, ''3-D Rock Properties Modeling for FY 1998'' (SNL 1997, WA-0358), ''3-D Rock Properties Modeling for FY 1999'' (SNL 1999), and the technical development plan, Rock Properties Model Version 3.1, (CRWMS MandO 1999c). The Interim Change Notice (ICNs), ICN 02 and ICN 03, of this AMR were prepared as part of activities being conducted under the Technical Work Plan, TWP-NBS-GS-000003, ''Technical Work Plan for the Integrated Site Model, Process Model Report, Revision 01'' (CRWMS MandO 2000b). The purpose of ICN 03 is to record changes in data input status due to data qualification and verification activities. These work plans describe the scope, objectives, tasks, methodology, and implementing procedures for model construction. The constraints, caveats, and limitations associated with this model are discussed in the appropriate text sections that follow. The work scope for this activity consists of the following: (1) Conversion of the input data (laboratory measured porosity data, x-ray diffraction mineralogy, petrophysical calculations of bound water, and petrophysical calculations of porosity) for each borehole into stratigraphic coordinates; (2) Re-sampling and merging of data sets; (3) Development of geostatistical simulations of porosity; (4

The trans-unit operation management system of VEAG AG`s power plant in Jaenschwalde; Das werksuebergreifende Betriebsmanagementsystem im Kraftwerk Jaenschwalde der VEAG AG

Energy Technology Data Exchange (ETDEWEB)

Weidich, H.; Platzke, R.

1997-12-31

Jaenschwalde coal power plant consists of 3 so-called ``modules`` of 2 power blocks each. The new operation management system at Jaenschwalde power plant has greatly improved the temporal availability and quality of process data needed by its various departments. The possibilities of process data analysis and the various optional extensions are capable of integration in various ways and at reasonable cost. At present the operation management system is managed by two employees. As the job does not even fully occupy these two, they are available for other work as well. In earlier times there were instead 6 process computers whose operation and maintenance occupied 30 employees. Beside these tremendous savings in labour the system has also brought about great functional improvements in terms of the supply of process data for the power plant as a whole and also for the entire VEAG network. [Deutsch] Das Braunkohlekraftwerk Jaenschwalde besteht aus insgesamt 6 Kraftwerksbloecken, von denen jeweils 2 Kraftwerksbloecke sogenannte `Module` bilden. Die zeitliche Verfuegbarkeit und die Guete der von den Fachabteilungen benoetigten Prozessdaten ist durch das neue Betriebsmanagementsystem im Kraftwerk Jaenschwalde drastisch erhoeht worden. Die Moeglichkeiten der Prozessdatenanalyse und die individuellen Erweiterungen sind vielseitig und mit einem ueberschaubaren Aufwand integrierbar. Die Pflege des gesamten heutigen Betriebsmanagementsystems wird heute von 2 Personen durchgefuehrt, die nicht einmal 100% ihrer Arbeitszeit dafuer aufzuwenden haben, so dass sie noch Aufgaben aus anderen Bereichen erledigen koennen. Frueher wurden dagegen 30 Personen fuer die Pflege und Wartung der 6 Prozessrechner benoetigt. Neben dem Einsparungspotential wurde eine grosse funktionelle Verbesserung fuer die Bereitstellung der Prozessdaten im gesamten Kraftwerk und darueber hinaus im gesamten VEAG-Netzwerk erreicht. (orig./RHM)

The Kyoto meeting has given a clear signal. The 3rd conference of signatory states to the UN Framework Convention on Climate Change: Current situation, negotiation dynamics, results; Kyoto-Gipfel hat deutliches Signal gesetzt. Die 3. VSK zur KRK: Ausgangslage, Verhandlungsdynamik, Ergebnis

Energy Technology Data Exchange (ETDEWEB)

Lamprecht, F.

1998-01-01

This third meeting of the Parties to the UN Framework Convention on Climate Change, held from 1-10 December 1997 in Kyoto/Japan, on which high expectations had been placed, just as on the Berlin meeting two years ago, has certainly not come up to expectations, but still agreed upon a Protocol that can be called an important signpost in international policy for protection of the environment. The envisaged greenhouse gas reduction by 5.2 per cent (of 1990 emissions) laid down in the Protocol, to be achieved by the industrialized countries either individually or by Joint Implementation over the period from 2008 until 2012, is a positive result considering the present situation. Although the agreed cutback falls short of the figures given by climate experts (who demand at least a 20% reduction by the year 2005), the obligation of the USA, the worldwide biggest emitter of greenhouse gases, to achieve a mandatory minimum cutback in emissions of 7% can be considered a big success. (orig./CB) [Deutsch] Auf der wie vor zwei Jahren in Berlin mit stark ueberzogenen Erwartungen ueberfrachteten 3. Vertragsstaatenkonferenz (VSK) zur Klimarahmenkonvention (KRK) vom 1.-10. Dezember 1997 in Kyoto/Japan ist ein zwar bescheidender, aber wichtiger Meilenstein der internationalen Umweltpoltik gesetzt worden. Die im Kyoto-Protokoll festgeschriebene, von den Industrielaendern individuell oder gemeinsam in der Periode 2008-2012 im Durchschnitt zu erzielende Treibhausgasreduktion von insgesamt 5,2% (Basis 1990) ist, gemessen an der Ausgangslage, positiv zu werten. Wenngleich damit die Forderung der Klimaforscher (mindestens 20%-Reduktion bis 2005) nicht erreicht wurde, muss die 7%-Minderungsverpflichtung des weltgroessten Treibhausgasemittenten USA als grosser Erfolg gesehen werden. (orig./RHM)

Automated protein structure modeling with SWISS-MODEL Workspace and the Protein Model Portal.

Science.gov (United States)

Bordoli, Lorenza; Schwede, Torsten

2012-01-01

Comparative protein structure modeling is a computational approach to build three-dimensional structural models for proteins using experimental structures of related protein family members as templates. Regular blind assessments of modeling accuracy have demonstrated that comparative protein structure modeling is currently the most reliable technique to model protein structures. Homology models are often sufficiently accurate to substitute for experimental structures in a wide variety of applications. Since the usefulness of a model for specific application is determined by its accuracy, model quality estimation is an essential component of protein structure prediction. Comparative protein modeling has become a routine approach in many areas of life science research since fully automated modeling systems allow also nonexperts to build reliable models. In this chapter, we describe practical approaches for automated protein structure modeling with SWISS-MODEL Workspace and the Protein Model Portal.

Geologic Framework Model Analysis Model Report

Energy Technology Data Exchange (ETDEWEB)

R. Clayton

2000-12-19

The purpose of this report is to document the Geologic Framework Model (GFM), Version 3.1 (GFM3.1) with regard to data input, modeling methods, assumptions, uncertainties, limitations, and validation of the model results, qualification status of the model, and the differences between Version 3.1 and previous versions. The GFM represents a three-dimensional interpretation of the stratigraphy and structural features of the location of the potential Yucca Mountain radioactive waste repository. The GFM encompasses an area of 65 square miles (170 square kilometers) and a volume of 185 cubic miles (771 cubic kilometers). The boundaries of the GFM were chosen to encompass the most widely distributed set of exploratory boreholes (the Water Table or WT series) and to provide a geologic framework over the area of interest for hydrologic flow and radionuclide transport modeling through the unsaturated zone (UZ). The depth of the model is constrained by the inferred depth of the Tertiary-Paleozoic unconformity. The GFM was constructed from geologic map and borehole data. Additional information from measured stratigraphy sections, gravity profiles, and seismic profiles was also considered. This interim change notice (ICN) was prepared in accordance with the Technical Work Plan for the Integrated Site Model Process Model Report Revision 01 (CRWMS M&O 2000). The constraints, caveats, and limitations associated with this model are discussed in the appropriate text sections that follow. The GFM is one component of the Integrated Site Model (ISM) (Figure l), which has been developed to provide a consistent volumetric portrayal of the rock layers, rock properties, and mineralogy of the Yucca Mountain site. The ISM consists of three components: (1) Geologic Framework Model (GFM); (2) Rock Properties Model (RPM); and (3) Mineralogic Model (MM). The ISM merges the detailed project stratigraphy into model stratigraphic units that are most useful for the primary downstream models and the

Geologic Framework Model Analysis Model Report

International Nuclear Information System (INIS)

Clayton, R.

2000-01-01

The purpose of this report is to document the Geologic Framework Model (GFM), Version 3.1 (GFM3.1) with regard to data input, modeling methods, assumptions, uncertainties, limitations, and validation of the model results, qualification status of the model, and the differences between Version 3.1 and previous versions. The GFM represents a three-dimensional interpretation of the stratigraphy and structural features of the location of the potential Yucca Mountain radioactive waste repository. The GFM encompasses an area of 65 square miles (170 square kilometers) and a volume of 185 cubic miles (771 cubic kilometers). The boundaries of the GFM were chosen to encompass the most widely distributed set of exploratory boreholes (the Water Table or WT series) and to provide a geologic framework over the area of interest for hydrologic flow and radionuclide transport modeling through the unsaturated zone (UZ). The depth of the model is constrained by the inferred depth of the Tertiary-Paleozoic unconformity. The GFM was constructed from geologic map and borehole data. Additional information from measured stratigraphy sections, gravity profiles, and seismic profiles was also considered. This interim change notice (ICN) was prepared in accordance with the Technical Work Plan for the Integrated Site Model Process Model Report Revision 01 (CRWMS M and O 2000). The constraints, caveats, and limitations associated with this model are discussed in the appropriate text sections that follow. The GFM is one component of the Integrated Site Model (ISM) (Figure l), which has been developed to provide a consistent volumetric portrayal of the rock layers, rock properties, and mineralogy of the Yucca Mountain site. The ISM consists of three components: (1) Geologic Framework Model (GFM); (2) Rock Properties Model (RPM); and (3) Mineralogic Model (MM). The ISM merges the detailed project stratigraphy into model stratigraphic units that are most useful for the primary downstream models and

Model(ing) Law

DEFF Research Database (Denmark)

Carlson, Kerstin

The International Criminal Tribunal for the former Yugoslavia (ICTY) was the first and most celebrated of a wave of international criminal tribunals (ICTs) built in the 1990s designed to advance liberalism through international criminal law. Model(ing) Justice examines the case law of the ICTY...

Comparisons of Multilevel Modeling and Structural Equation Modeling Approaches to Actor-Partner Interdependence Model.

Science.gov (United States)

Hong, Sehee; Kim, Soyoung

2018-01-01

There are basically two modeling approaches applicable to analyzing an actor-partner interdependence model: the multilevel modeling (hierarchical linear model) and the structural equation modeling. This article explains how to use these two models in analyzing an actor-partner interdependence model and how these two approaches work differently. As an empirical example, marital conflict data were used to analyze an actor-partner interdependence model. The multilevel modeling and the structural equation modeling produced virtually identical estimates for a basic model. However, the structural equation modeling approach allowed more realistic assumptions on measurement errors and factor loadings, rendering better model fit indices.

Translating building information modeling to building energy modeling using model view definition.

Science.gov (United States)

Jeong, WoonSeong; Kim, Jong Bum; Clayton, Mark J; Haberl, Jeff S; Yan, Wei

2014-01-01

This paper presents a new approach to translate between Building Information Modeling (BIM) and Building Energy Modeling (BEM) that uses Modelica, an object-oriented declarative, equation-based simulation environment. The approach (BIM2BEM) has been developed using a data modeling method to enable seamless model translations of building geometry, materials, and topology. Using data modeling, we created a Model View Definition (MVD) consisting of a process model and a class diagram. The process model demonstrates object-mapping between BIM and Modelica-based BEM (ModelicaBEM) and facilitates the definition of required information during model translations. The class diagram represents the information and object relationships to produce a class package intermediate between the BIM and BEM. The implementation of the intermediate class package enables system interface (Revit2Modelica) development for automatic BIM data translation into ModelicaBEM. In order to demonstrate and validate our approach, simulation result comparisons have been conducted via three test cases using (1) the BIM-based Modelica models generated from Revit2Modelica and (2) BEM models manually created using LBNL Modelica Buildings library. Our implementation shows that BIM2BEM (1) enables BIM models to be translated into ModelicaBEM models, (2) enables system interface development based on the MVD for thermal simulation, and (3) facilitates the reuse of original BIM data into building energy simulation without an import/export process.

Translating Building Information Modeling to Building Energy Modeling Using Model View Definition

Directory of Open Access Journals (Sweden)

WoonSeong Jeong

2014-01-01

Full Text Available This paper presents a new approach to translate between Building Information Modeling (BIM and Building Energy Modeling (BEM that uses Modelica, an object-oriented declarative, equation-based simulation environment. The approach (BIM2BEM has been developed using a data modeling method to enable seamless model translations of building geometry, materials, and topology. Using data modeling, we created a Model View Definition (MVD consisting of a process model and a class diagram. The process model demonstrates object-mapping between BIM and Modelica-based BEM (ModelicaBEM and facilitates the definition of required information during model translations. The class diagram represents the information and object relationships to produce a class package intermediate between the BIM and BEM. The implementation of the intermediate class package enables system interface (Revit2Modelica development for automatic BIM data translation into ModelicaBEM. In order to demonstrate and validate our approach, simulation result comparisons have been conducted via three test cases using (1 the BIM-based Modelica models generated from Revit2Modelica and (2 BEM models manually created using LBNL Modelica Buildings library. Our implementation shows that BIM2BEM (1 enables BIM models to be translated into ModelicaBEM models, (2 enables system interface development based on the MVD for thermal simulation, and (3 facilitates the reuse of original BIM data into building energy simulation without an import/export process.

Models Archive and ModelWeb at NSSDC

Science.gov (United States)

Bilitza, D.; Papitashvili, N.; King, J. H.

2002-05-01

In addition to its large data holdings, NASA's National Space Science Data Center (NSSDC) also maintains an archive of space physics models for public use (ftp://nssdcftp.gsfc.nasa.gov/models/). The more than 60 model entries cover a wide range of parameters from the atmosphere, to the ionosphere, to the magnetosphere, to the heliosphere. The models are primarily empirical models developed by the respective model authors based on long data records from ground and space experiments. An online model catalog (http://nssdc.gsfc.nasa.gov/space/model/) provides information about these and other models and links to the model software if available. We will briefly review the existing model holdings and highlight some of its usages and users. In response to a growing need by the user community, NSSDC began to develop web-interfaces for the most frequently requested models. These interfaces enable users to compute and plot model parameters online for the specific conditions that they are interested in. Currently included in the Modelweb system (http://nssdc.gsfc.nasa.gov/space/model/) are the following models: the International Reference Ionosphere (IRI) model, the Mass Spectrometer Incoherent Scatter (MSIS) E90 model, the International Geomagnetic Reference Field (IGRF) and the AP/AE-8 models for the radiation belt electrons and protons. User accesses to both systems have been steadily increasing over the last years with occasional spikes prior to large scientific meetings. The current monthly rate is between 5,000 to 10,000 accesses for either system; in February 2002 13,872 accesses were recorded to the Modelsweb and 7092 accesses to the models archive.

Modelling the models

CERN Multimedia

Anaïs Schaeffer

2012-01-01

By analysing the production of mesons in the forward region of LHC proton-proton collisions, the LHCf collaboration has provided key information needed to calibrate extremely high-energy cosmic ray models.   Average transverse momentum (pT) as a function of rapidity loss ∆y. Black dots represent LHCf data and the red diamonds represent SPS experiment UA7 results. The predictions of hadronic interaction models are shown by open boxes (sibyll 2.1), open circles (qgsjet II-03) and open triangles (epos 1.99). Among these models, epos 1.99 shows the best overall agreement with the LHCf data. LHCf is dedicated to the measurement of neutral particles emitted at extremely small angles in the very forward region of LHC collisions. Two imaging calorimeters – Arm1 and Arm2 – take data 140 m either side of the ATLAS interaction point. “The physics goal of this type of analysis is to provide data for calibrating the hadron interaction models – the well-known &...

Model Manipulation for End-User Modelers

DEFF Research Database (Denmark)

Acretoaie, Vlad

, and transformations using their modeling notation and editor of choice. The VM* languages are implemented via a single execution engine, the VM* Runtime, built on top of the Henshin graph-based transformation engine. This approach combines the benefits of flexibility, maturity, and formality. To simplify model editor......End-user modelers are domain experts who create and use models as part of their work. They are typically not Software Engineers, and have little or no programming and meta-modeling experience. However, using model manipulation languages developed in the context of Model-Driven Engineering often...... requires such experience. These languages are therefore only used by a small subset of the modelers that could, in theory, benefit from them. The goals of this thesis are to substantiate this observation, introduce the concepts and tools required to overcome it, and provide empirical evidence in support...

Modeling energy-economy interactions using integrated models

International Nuclear Information System (INIS)

Uyterlinde, M.A.

1994-06-01

Integrated models are defined as economic energy models that consist of several submodels, either coupled by an interface module, or embedded in one large model. These models can be used for energy policy analysis. Using integrated models yields the following benefits. They provide a framework in which energy-economy interactions can be better analyzed than in stand-alone models. Integrated models can represent both energy sector technological details, as well as the behaviour of the market and the role of prices. Furthermore, the combination of modeling methodologies in one model can compensate weaknesses of one approach with strengths of another. These advantages motivated this survey of the class of integrated models. The purpose of this literature survey therefore was to collect and to present information on integrated models. To carry out this task, several goals were identified. The first goal was to give an overview of what is reported on these models in general. The second one was to find and describe examples of such models. Other goals were to find out what kinds of models were used as component models, and to examine the linkage methodology. Solution methods and their convergence properties were also a subject of interest. The report has the following structure. In chapter 2, a 'conceptual framework' is given. In chapter 3 a number of integrated models is described. In a table, a complete overview is presented of all described models. Finally, in chapter 4, the report is summarized, and conclusions are drawn regarding the advantages and drawbacks of integrated models. 8 figs., 29 refs

On the role of model structure in hydrological modeling : Understanding models

NARCIS (Netherlands)

Gharari, S.

2016-01-01

Modeling is an essential part of the science of hydrology. Models enable us to formulate what we know and perceive from the real world into a neat package. Rainfall-runoff models are abstract simplifications of how a catchment works. Within the research field of scientific rainfall-runoff modeling,

Evolution of computational models in BioModels Database and the Physiome Model Repository.

Science.gov (United States)

Scharm, Martin; Gebhardt, Tom; Touré, Vasundra; Bagnacani, Andrea; Salehzadeh-Yazdi, Ali; Wolkenhauer, Olaf; Waltemath, Dagmar

2018-04-12

A useful model is one that is being (re)used. The development of a successful model does not finish with its publication. During reuse, models are being modified, i.e. expanded, corrected, and refined. Even small changes in the encoding of a model can, however, significantly affect its interpretation. Our motivation for the present study is to identify changes in models and make them transparent and traceable. We analysed 13734 models from BioModels Database and the Physiome Model Repository. For each model, we studied the frequencies and types of updates between its first and latest release. To demonstrate the impact of changes, we explored the history of a Repressilator model in BioModels Database. We observed continuous updates in the majority of models. Surprisingly, even the early models are still being modified. We furthermore detected that many updates target annotations, which improves the information one can gain from models. To support the analysis of changes in model repositories we developed MoSt, an online tool for visualisations of changes in models. The scripts used to generate the data and figures for this study are available from GitHub https://github.com/binfalse/BiVeS-StatsGenerator and as a Docker image at https://hub.docker.com/r/binfalse/bives-statsgenerator/ . The website https://most.bio.informatik.uni-rostock.de/ provides interactive access to model versions and their evolutionary statistics. The reuse of models is still impeded by a lack of trust and documentation. A detailed and transparent documentation of all aspects of the model, including its provenance, will improve this situation. Knowledge about a model's provenance can avoid the repetition of mistakes that others already faced. More insights are gained into how the system evolves from initial findings to a profound understanding. We argue that it is the responsibility of the maintainers of model repositories to offer transparent model provenance to their users.

Model documentation report: Transportation sector model of the National Energy Modeling System

Energy Technology Data Exchange (ETDEWEB)

1994-03-01

This report documents the objectives, analytical approach and development of the National Energy Modeling System (NEMS) Transportation Model (TRAN). The report catalogues and describes the model assumptions, computational methodology, parameter estimation techniques, model source code, and forecast results generated by the model. This document serves three purposes. First, it is a reference document providing a detailed description of TRAN for model analysts, users, and the public. Second, this report meets the legal requirements of the Energy Information Administration (EIA) to provide adequate documentation in support of its statistical and forecast reports (Public Law 93-275, 57(b)(1)). Third, it permits continuity in model development by providing documentation from which energy analysts can undertake model enhancements, data updates, and parameter refinements.

Modeling complexes of modeled proteins.

Science.gov (United States)

Anishchenko, Ivan; Kundrotas, Petras J; Vakser, Ilya A

2017-03-01

Structural characterization of proteins is essential for understanding life processes at the molecular level. However, only a fraction of known proteins have experimentally determined structures. This fraction is even smaller for protein-protein complexes. Thus, structural modeling of protein-protein interactions (docking) primarily has to rely on modeled structures of the individual proteins, which typically are less accurate than the experimentally determined ones. Such "double" modeling is the Grand Challenge of structural reconstruction of the interactome. Yet it remains so far largely untested in a systematic way. We present a comprehensive validation of template-based and free docking on a set of 165 complexes, where each protein model has six levels of structural accuracy, from 1 to 6 Å C α RMSD. Many template-based docking predictions fall into acceptable quality category, according to the CAPRI criteria, even for highly inaccurate proteins (5-6 Å RMSD), although the number of such models (and, consequently, the docking success rate) drops significantly for models with RMSD > 4 Å. The results show that the existing docking methodologies can be successfully applied to protein models with a broad range of structural accuracy, and the template-based docking is much less sensitive to inaccuracies of protein models than the free docking. Proteins 2017; 85:470-478. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Modeling styles in business process modeling

NARCIS (Netherlands)

Pinggera, J.; Soffer, P.; Zugal, S.; Weber, B.; Weidlich, M.; Fahland, D.; Reijers, H.A.; Mendling, J.; Bider, I.; Halpin, T.; Krogstie, J.; Nurcan, S.; Proper, E.; Schmidt, R.; Soffer, P.; Wrycza, S.

2012-01-01

Research on quality issues of business process models has recently begun to explore the process of creating process models. As a consequence, the question arises whether different ways of creating process models exist. In this vein, we observed 115 students engaged in the act of modeling, recording

Comparison: Binomial model and Black Scholes model

Directory of Open Access Journals (Sweden)

Amir Ahmad Dar

2018-03-01

Full Text Available The Binomial Model and the Black Scholes Model are the popular methods that are used to solve the option pricing problems. Binomial Model is a simple statistical method and Black Scholes model requires a solution of a stochastic differential equation. Pricing of European call and a put option is a very difficult method used by actuaries. The main goal of this study is to differentiate the Binominal model and the Black Scholes model by using two statistical model - t-test and Tukey model at one period. Finally, the result showed that there is no significant difference between the means of the European options by using the above two models.

Modelling in Business Model design

NARCIS (Netherlands)

Simonse, W.L.

2013-01-01

It appears that business model design might not always produce a design or model as the expected result. However when designers are involved, a visual model or artefact is produced. To assist strategic managers in thinking about how they can act, the designers challenge is to combine strategy and

Modelling SDL, Modelling Languages

Directory of Open Access Journals (Sweden)

Michael Piefel

2007-02-01

Full Text Available Today's software systems are too complex to implement them and model them using only one language. As a result, modern software engineering uses different languages for different levels of abstraction and different system aspects. Thus to handle an increasing number of related or integrated languages is the most challenging task in the development of tools. We use object oriented metamodelling to describe languages. Object orientation allows us to derive abstract reusable concept definitions (concept classes from existing languages. This language definition technique concentrates on semantic abstractions rather than syntactical peculiarities. We present a set of common concept classes that describe structure, behaviour, and data aspects of high-level modelling languages. Our models contain syntax modelling using the OMG MOF as well as static semantic constraints written in OMG OCL. We derive metamodels for subsets of SDL and UML from these common concepts, and we show for parts of these languages that they can be modelled and related to each other through the same abstract concepts.

Model integration and a theory of models

OpenAIRE

Dolk, Daniel R.; Kottemann, Jeffrey E.

1993-01-01

Model integration extends the scope of model management to include the dimension of manipulation as well. This invariably leads to comparisons with database theory. Model integration is viewed from four perspectives: Organizational, definitional, procedural, and implementational. Strategic modeling is discussed as the organizational motivation for model integration. Schema and process integration are examined as the logical and manipulation counterparts of model integr...

Did a whole-crustal hydrothermal system generate the Irish Zn-Pb orefield?

Science.gov (United States)

Daly, J. Stephen; Badenszki, Eszter; Chew, David; Kronz, Andreas; O'Rourke, Helen; Whitehouse, Martin; Menuge, Julian; van den Berg, Riana

2016-04-01

Current models[1] for the genesis of the giant Irish Carboniferous-hosted Zn-Pb orefield propose shallow (700°C) metamorphism and melting during the Acadian orogeny at ~390Ma and during separate episodes of extension at ~ 381-373Ma and ~362Ma. Sm-Nd garnet dating shows that the lower crust remained hot or was re-heated to ~600°C at ~341Ma during Lower Carboniferous volcanism, also associated with extension and, in part, coincident with the mineralization[1]. Isotopic data from the xenoliths correspond closely to Sr and Nd isotopic analyses of gangue calcite[8] and galena Pb[9] isotopic data from the major ore deposits. While Zn contents of the xenoliths permit them to be metal sources, their mineralogy and texture provide an enriched template and a plausible extraction mechanism. In situ analyses of modally-abundant biotite and garnet show significant enrichment in Zn (and other relevant metals) as well as order of magnitude depletion of Zn during retrograde alteration, providing a metal-release mechanism and pointing to a hydrothermal fluid system operating at least to depths of ~ 25km. References [1] Wilkinson, J.J. & Hitzman, M.W. 2015. The Irish Pb-Zn orefield: The view from 2014. In: Archibald, S.M. and Piercey, S.J. (eds) Current Perspectives on Zinc deposits. Irish Association for Economic Geology, pp. 59-72.; [2] Davidheiser-Kroll, B., Stuart, F.M. & Boyce, A.J. 2014. Mineralium Deposita, 49, 547-553; [3] Elliott, H. 2015. Unpublished PhD thesis, University of Southampton; [4] Hnatyshin, D., Creaser, R.A., Wilkinson, J.J. & Gleeson, S.A. 2015. Geology, 43, 143-146; [5] McCusker, J. & Reed, C. 2013. Mineralium Deposita, 48, 687-695; [6] Van den Berg, R., Daly, J.S. & Salisbury, M.H. 2005. Tectonophysics, 407(1-2), 81-99; [7] Hauser, F., O'Reilly, B.M., Readman, P.W., Daly, J. S. & Van den Berg, R. 2008. Geophysical Journal International 175, 1254-1272; [8] Walshaw, R.D., Menuge, J.F. & Tyrrell, S. 2006. Mineralium Deposita, 41, 803-819; [9] Everett, C

Integrated Site Model Process Model Report

International Nuclear Information System (INIS)

Booth, T.

2000-01-01

The Integrated Site Model (ISM) provides a framework for discussing the geologic features and properties of Yucca Mountain, which is being evaluated as a potential site for a geologic repository for the disposal of nuclear waste. The ISM is important to the evaluation of the site because it provides 3-D portrayals of site geologic, rock property, and mineralogic characteristics and their spatial variabilities. The ISM is not a single discrete model; rather, it is a set of static representations that provide three-dimensional (3-D), computer representations of site geology, selected hydrologic and rock properties, and mineralogic-characteristics data. These representations are manifested in three separate model components of the ISM: the Geologic Framework Model (GFM), the Rock Properties Model (RPM), and the Mineralogic Model (MM). The GFM provides a representation of the 3-D stratigraphy and geologic structure. Based on the framework provided by the GFM, the RPM and MM provide spatial simulations of the rock and hydrologic properties, and mineralogy, respectively. Functional summaries of the component models and their respective output are provided in Section 1.4. Each of the component models of the ISM considers different specific aspects of the site geologic setting. Each model was developed using unique methodologies and inputs, and the determination of the modeled units for each of the components is dependent on the requirements of that component. Therefore, while the ISM represents the integration of the rock properties and mineralogy into a geologic framework, the discussion of ISM construction and results is most appropriately presented in terms of the three separate components. This Process Model Report (PMR) summarizes the individual component models of the ISM (the GFM, RPM, and MM) and describes how the three components are constructed and combined to form the ISM

Concept Modeling vs. Data modeling in Practice

DEFF Research Database (Denmark)

Madsen, Bodil Nistrup; Erdman Thomsen, Hanne

2015-01-01

This chapter shows the usefulness of terminological concept modeling as a first step in data modeling. First, we introduce terminological concept modeling with terminological ontologies, i.e. concept systems enriched with characteristics modeled as feature specifications. This enables a formal...... account of the inheritance of characteristics and allows us to introduce a number of principles and constraints which render concept modeling more coherent than earlier approaches. Second, we explain how terminological ontologies can be used as the basis for developing conceptual and logical data models....... We also show how to map from the various elements in the terminological ontology to elements in the data models, and explain the differences between the models. Finally the usefulness of terminological ontologies as a prerequisite for IT development and data modeling is illustrated with examples from...

Automated Protein Structure Modeling with SWISS-MODEL Workspace and the Protein Model Portal

OpenAIRE

Bordoli, Lorenza; Schwede, Torsten

2012-01-01

Comparative protein structure modeling is a computational approach to build three-dimensional structural models for proteins using experimental structures of related protein family members as templates. Regular blind assessments of modeling accuracy have demonstrated that comparative protein structure modeling is currently the most reliable technique to model protein structures. Homology models are often sufficiently accurate to substitute for experimental structures in a wide variety of appl...

Model documentation report: Transportation sector model of the National Energy Modeling System

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-02-01

Over the past year, several modifications have been made to the NEMS Transportation Model, incorporating greater levels of detail and analysis in modules previously represented in the aggregate or under a profusion of simplifying assumptions. This document is intended to amend those sections of the Model Documentation Report (MDR) which describe these superseded modules. Significant changes have been implemented in the LDV Fuel Economy Model, the Alternative Fuel Vehicle Model, the LDV Fleet Module, and the Highway Freight Model. The relevant sections of the MDR have been extracted from the original document, amended, and are presented in the following pages. A brief summary of the modifications follows: In the Fuel Economy Model, modifications have been made which permit the user to employ more optimistic assumptions about the commercial viability and impact of selected technological improvements. This model also explicitly calculates the fuel economy of an array of alternative fuel vehicles (AFV`s) which are subsequently used in the estimation of vehicle sales. In the Alternative Fuel Vehicle Model, the results of the Fuel Economy Model have been incorporated, and the program flows have been modified to reflect that fact. In the Light Duty Vehicle Fleet Module, the sales of vehicles to fleets of various size are endogenously calculated in order to provide a more detailed estimate of the impacts of EPACT legislation on the sales of AFV`s to fleets. In the Highway Freight Model, the previous aggregate estimation has been replaced by a detailed Freight Truck Stock Model, where travel patterns, efficiencies, and energy intensities are estimated by industrial grouping. Several appendices are provided at the end of this document, containing data tables and supplementary descriptions of the model development process which are not integral to an understanding of the overall model structure.

The IMACLIM model; Le modele IMACLIM

Energy Technology Data Exchange (ETDEWEB)

NONE

2003-07-01

This document provides annexes to the IMACLIM model which propose an actualized description of IMACLIM, model allowing the design of an evaluation tool of the greenhouse gases reduction policies. The model is described in a version coupled with the POLES, technical and economical model of the energy industry. Notations, equations, sources, processing and specifications are proposed and detailed. (A.L.B.)

Modelling Practice

DEFF Research Database (Denmark)

Cameron, Ian; Gani, Rafiqul

2011-01-01

This chapter deals with the practicalities of building, testing, deploying and maintaining models. It gives specific advice for each phase of the modelling cycle. To do this, a modelling framework is introduced which covers: problem and model definition; model conceptualization; model data...... requirements; model construction; model solution; model verification; model validation and finally model deployment and maintenance. Within the adopted methodology, each step is discussedthrough the consideration of key issues and questions relevant to the modelling activity. Practical advice, based on many...

Leadership Models.

Science.gov (United States)

Freeman, Thomas J.

This paper discusses six different models of organizational structure and leadership, including the scalar chain or pyramid model, the continuum model, the grid model, the linking pin model, the contingency model, and the circle or democratic model. Each model is examined in a separate section that describes the model and its development, lists…

Cognitive models embedded in system simulation models

International Nuclear Information System (INIS)

Siegel, A.I.; Wolf, J.J.

1982-01-01

If we are to discuss and consider cognitive models, we must first come to grips with two questions: (1) What is cognition; (2) What is a model. Presumably, the answers to these questions can provide a basis for defining a cognitive model. Accordingly, this paper first places these two questions into perspective. Then, cognitive models are set within the context of computer simulation models and a number of computer simulations of cognitive processes are described. Finally, pervasive issues are discussed vis-a-vis cognitive modeling in the computer simulation context

Better models are more effectively connected models

Science.gov (United States)

Nunes, João Pedro; Bielders, Charles; Darboux, Frederic; Fiener, Peter; Finger, David; Turnbull-Lloyd, Laura; Wainwright, John

2016-04-01

The concept of hydrologic and geomorphologic connectivity describes the processes and pathways which link sources (e.g. rainfall, snow and ice melt, springs, eroded areas and barren lands) to accumulation areas (e.g. foot slopes, streams, aquifers, reservoirs), and the spatial variations thereof. There are many examples of hydrological and sediment connectivity on a watershed scale; in consequence, a process-based understanding of connectivity is crucial to help managers understand their systems and adopt adequate measures for flood prevention, pollution mitigation and soil protection, among others. Modelling is often used as a tool to understand and predict fluxes within a catchment by complementing observations with model results. Catchment models should therefore be able to reproduce the linkages, and thus the connectivity of water and sediment fluxes within the systems under simulation. In modelling, a high level of spatial and temporal detail is desirable to ensure taking into account a maximum number of components, which then enables connectivity to emerge from the simulated structures and functions. However, computational constraints and, in many cases, lack of data prevent the representation of all relevant processes and spatial/temporal variability in most models. In most cases, therefore, the level of detail selected for modelling is too coarse to represent the system in a way in which connectivity can emerge; a problem which can be circumvented by representing fine-scale structures and processes within coarser scale models using a variety of approaches. This poster focuses on the results of ongoing discussions on modelling connectivity held during several workshops within COST Action Connecteur. It assesses the current state of the art of incorporating the concept of connectivity in hydrological and sediment models, as well as the attitudes of modellers towards this issue. The discussion will focus on the different approaches through which connectivity

Constructive Epistemic Modeling: A Hierarchical Bayesian Model Averaging Method

Science.gov (United States)

Tsai, F. T. C.; Elshall, A. S.

2014-12-01

Constructive epistemic modeling is the idea that our understanding of a natural system through a scientific model is a mental construct that continually develops through learning about and from the model. Using the hierarchical Bayesian model averaging (HBMA) method [1], this study shows that segregating different uncertain model components through a BMA tree of posterior model probabilities, model prediction, within-model variance, between-model variance and total model variance serves as a learning tool [2]. First, the BMA tree of posterior model probabilities permits the comparative evaluation of the candidate propositions of each uncertain model component. Second, systemic model dissection is imperative for understanding the individual contribution of each uncertain model component to the model prediction and variance. Third, the hierarchical representation of the between-model variance facilitates the prioritization of the contribution of each uncertain model component to the overall model uncertainty. We illustrate these concepts using the groundwater modeling of a siliciclastic aquifer-fault system. The sources of uncertainty considered are from geological architecture, formation dip, boundary conditions and model parameters. The study shows that the HBMA analysis helps in advancing knowledge about the model rather than forcing the model to fit a particularly understanding or merely averaging several candidate models. [1] Tsai, F. T.-C., and A. S. Elshall (2013), Hierarchical Bayesian model averaging for hydrostratigraphic modeling: Uncertainty segregation and comparative evaluation. Water Resources Research, 49, 5520-5536, doi:10.1002/wrcr.20428. [2] Elshall, A.S., and F. T.-C. Tsai (2014). Constructive epistemic modeling of groundwater flow with geological architecture and boundary condition uncertainty under Bayesian paradigm, Journal of Hydrology, 517, 105-119, doi: 10.1016/j.jhydrol.2014.05.027.

Models and role models

NARCIS (Netherlands)

ten Cate, J.M.

2015-01-01

Developing experimental models to understand dental caries has been the theme in our research group. Our first, the pH-cycling model, was developed to investigate the chemical reactions in enamel or dentine, which lead to dental caries. It aimed to leverage our understanding of the fluoride mode of

Multiscale musculoskeletal modelling, data–model fusion and electromyography-informed modelling

Science.gov (United States)

Zhang, J.; Heidlauf, T.; Sartori, M.; Besier, T.; Röhrle, O.; Lloyd, D.

2016-01-01

This paper proposes methods and technologies that advance the state of the art for modelling the musculoskeletal system across the spatial and temporal scales; and storing these using efficient ontologies and tools. We present population-based modelling as an efficient method to rapidly generate individual morphology from only a few measurements and to learn from the ever-increasing supply of imaging data available. We present multiscale methods for continuum muscle and bone models; and efficient mechanostatistical methods, both continuum and particle-based, to bridge the scales. Finally, we examine both the importance that muscles play in bone remodelling stimuli and the latest muscle force prediction methods that use electromyography-assisted modelling techniques to compute musculoskeletal forces that best reflect the underlying neuromuscular activity. Our proposal is that, in order to have a clinically relevant virtual physiological human, (i) bone and muscle mechanics must be considered together; (ii) models should be trained on population data to permit rapid generation and use underlying principal modes that describe both muscle patterns and morphology; and (iii) these tools need to be available in an open-source repository so that the scientific community may use, personalize and contribute to the database of models. PMID:27051510

Atmospheric statistical dynamic models. Model performance: the Lawrence Livermore Laboratoy Zonal Atmospheric Model

International Nuclear Information System (INIS)

Potter, G.L.; Ellsaesser, H.W.; MacCracken, M.C.; Luther, F.M.

1978-06-01

Results from the zonal model indicate quite reasonable agreement with observation in terms of the parameters and processes that influence the radiation and energy balance calculations. The model produces zonal statistics similar to those from general circulation models, and has also been shown to produce similar responses in sensitivity studies. Further studies of model performance are planned, including: comparison with July data; comparison of temperature and moisture transport and wind fields for winter and summer months; and a tabulation of atmospheric energetics. Based on these preliminary performance studies, however, it appears that the zonal model can be used in conjunction with more complex models to help unravel the problems of understanding the processes governing present climate and climate change. As can be seen in the subsequent paper on model sensitivity studies, in addition to reduced cost of computation, the zonal model facilitates analysis of feedback mechanisms and simplifies analysis of the interactions between processes

Gradient-based model calibration with proxy-model assistance

Science.gov (United States)

Burrows, Wesley; Doherty, John

2016-02-01

Use of a proxy model in gradient-based calibration and uncertainty analysis of a complex groundwater model with large run times and problematic numerical behaviour is described. The methodology is general, and can be used with models of all types. The proxy model is based on a series of analytical functions that link all model outputs used in the calibration process to all parameters requiring estimation. In enforcing history-matching constraints during the calibration and post-calibration uncertainty analysis processes, the proxy model is run for the purposes of populating the Jacobian matrix, while the original model is run when testing parameter upgrades; the latter process is readily parallelized. Use of a proxy model in this fashion dramatically reduces the computational burden of complex model calibration and uncertainty analysis. At the same time, the effect of model numerical misbehaviour on calculation of local gradients is mitigated, this allowing access to the benefits of gradient-based analysis where lack of integrity in finite-difference derivatives calculation would otherwise have impeded such access. Construction of a proxy model, and its subsequent use in calibration of a complex model, and in analysing the uncertainties of predictions made by that model, is implemented in the PEST suite.

Spike Neural Models Part II: Abstract Neural Models

Directory of Open Access Journals (Sweden)

Johnson, Melissa G.

2018-02-01

Full Text Available Neurons are complex cells that require a lot of time and resources to model completely. In spiking neural networks (SNN though, not all that complexity is required. Therefore simple, abstract models are often used. These models save time, use less computer resources, and are easier to understand. This tutorial presents two such models: Izhikevich's model, which is biologically realistic in the resulting spike trains but not in the parameters, and the Leaky Integrate and Fire (LIF model which is not biologically realistic but does quickly and easily integrate input to produce spikes. Izhikevich's model is based on Hodgkin-Huxley's model but simplified such that it uses only two differentiation equations and four parameters to produce various realistic spike patterns. LIF is based on a standard electrical circuit and contains one equation. Either of these two models, or any of the many other models in literature can be used in a SNN. Choosing a neural model is an important task that depends on the goal of the research and the resources available. Once a model is chosen, network decisions such as connectivity, delay, and sparseness, need to be made. Understanding neural models and how they are incorporated into the network is the first step in creating a SNN.

Population balance models: a useful complementary modelling framework for future WWTP modelling

DEFF Research Database (Denmark)

Nopens, Ingmar; Torfs, Elena; Ducoste, Joel

2015-01-01

Population balance models (PBMs) represent a powerful modelling framework for the description of the dynamics of properties that are characterised by distributions. This distribution of properties under transient conditions has been demonstrated in many chemical engineering applications. Modelling...

From Product Models to Product State Models

DEFF Research Database (Denmark)

Larsen, Michael Holm

1999-01-01

A well-known technology designed to handle product data is Product Models. Product Models are in their current form not able to handle all types of product state information. Hence, the concept of a Product State Model (PSM) is proposed. The PSM and in particular how to model a PSM is the Research...

North American Carbon Project (NACP) Regional Model-Model and Model-Data Intercomparison Project

Science.gov (United States)

Huntzinger, D. N.; Post, W. M.; Jacobson, A. R.; Cook, R. B.

2009-05-01

Available observations are localized and widely separated in both space and time, so we depend heavily on models to characterize, understand, and predict carbon fluxes at regional and global scales. The results from each model differ because they use different approaches (forward vs. inverse), modeling strategies (detailed process, statistical, observation based), process representation, boundary conditions, initial conditions, and driver data. To investigate these differences we conducted a model-model and model-data comparison using available forward ecosystem model and atmospheric inverse output, along with regional scale inventory data. Forward or "bottom-up" models typically estimate carbon fluxes through a set of physiological relationships, and are based on our current mechanistic understanding of how carbon is exchanged within ecosystems. Inverse or "top-down" analyses use measured atmospheric concentrations of CO2, coupled with an atmospheric transport model to infer surface flux distributions. Although bottom-up models do fairly well at reproducing measured fluxes (i.e., net ecosystem exchange) at a given location, they vary considerably in their estimates of carbon flux over regional or continental scales, suggesting difficulty in scaling mechanistic relationships to large areas and/or timescales. Conversely, top-down inverse models predict fluxes that are quantitatively consistent with atmospheric measurements, suggesting that they are capturing large scale variability in flux quite well, but offer limited insights into the processes controlling this variability and how fluxes vary at fine spatial scales. The analyses focused on identifying and quantifying spatial and temporal patterns of carbon fluxes among the models; quantifying across-model variability, as well as comparing simulated or estimated surface fluxes and biomass to observed values at regional to continental scales for the period 2000-2005. The analysis focused on the following three

Population Balance Models: A useful complementary modelling framework for future WWTP modelling

DEFF Research Database (Denmark)

Nopens, Ingmar; Torfs, Elena; Ducoste, Joel

2014-01-01

Population Balance Models (PBMs) represent a powerful modelling framework for the description of the dynamics of properties that are characterised by statistical distributions. This has been demonstrated in many chemical engineering applications. Modelling efforts of several current and future unit...

Model Metric untuk Mengukur Fleksibilitas Model Proses Bisnis

Directory of Open Access Journals (Sweden)

Endang Wahyu Pamungkas

2014-10-01

Full Text Available Abstrak Organisasi bisnis dunia saat ini banyak memanfaatkan sistem informasi digital untuk memberikan pemahaman mengenai manajemen proses bisnis yang mereka jalani. Pemanfaatan sistem Enterprise Resource Planning (ERP merupakan contoh teknologi dalam manajemen proses bisnis. Melalui sistem ini perusahaan dapat membangun dan mengembangkan proses bisnis. Selain itu, perusahaan juga dapat menyesuaikan proses bisnis secara cepat terhadap perubahan yang terjadi seiring bertambahnya kebutuhan dan informasi, berubahnya kondisi pasar, atau perubahan kebijakan. Sehubungan dengan perubahan proses bisnis yang sering terjadi, maka aspek fleksibilitas terhadap model proses yang dibangun harus ditingkatkan. Dalam mendukung peningkatan fleksibilitas tersebut tentunya dibutuhkan sebuah model untuk mengukur tingkat flesibelitas model proses bisnis. Model tersebut yang kemudian dapat digunakan oleh analis untuk melakukan perbandingan sehingga dapat diperoleh model proses bisnis yang paling fleksibel dan cocok dengan perusahaan. Hal ini dapat dianalisa dengan melibatkan aspek-aspek fleksibel yang telah diteliti pada penelitian-penelitian sebelumnya. Dalam paper ini akan dilakukan penelitian mengenai aspek fleksibitas dalam model proses bisnis untuk menghasilkan model metric yang dapat melakukan kuantifikasi tingkat fleksibilitas pada model proses bisnis. Model metric yang dihasilkan pada penelitian ini mampu melakukan perhitungan fleksibelitas pada model proses bisnis secara kuantitatif. Kata kunci: ERP, fleksibilitas, metadata, model metric, model proses bisnis, variasi Abstract Recently, business organizations in the world are making use of digital information systems to provide an understanding of the business process management in which they live. Utilization of Enterprise Resource Planning (ERP system is an example of technology in business process management. Through this system, some companies can build and develop business process and can quickly adjust

Modelling bankruptcy prediction models in Slovak companies

Directory of Open Access Journals (Sweden)

Kovacova Maria

2017-01-01

Full Text Available An intensive research from academics and practitioners has been provided regarding models for bankruptcy prediction and credit risk management. In spite of numerous researches focusing on forecasting bankruptcy using traditional statistics techniques (e.g. discriminant analysis and logistic regression and early artificial intelligence models (e.g. artificial neural networks, there is a trend for transition to machine learning models (support vector machines, bagging, boosting, and random forest to predict bankruptcy one year prior to the event. Comparing the performance of this with unconventional approach with results obtained by discriminant analysis, logistic regression, and neural networks application, it has been found that bagging, boosting, and random forest models outperform the others techniques, and that all prediction accuracy in the testing sample improves when the additional variables are included. On the other side the prediction accuracy of old and well known bankruptcy prediction models is quiet high. Therefore, we aim to analyse these in some way old models on the dataset of Slovak companies to validate their prediction ability in specific conditions. Furthermore, these models will be modelled according to new trends by calculating the influence of elimination of selected variables on the overall prediction ability of these models.

The ModelCC Model-Driven Parser Generator

Directory of Open Access Journals (Sweden)

Fernando Berzal

2015-01-01

Full Text Available Syntax-directed translation tools require the specification of a language by means of a formal grammar. This grammar must conform to the specific requirements of the parser generator to be used. This grammar is then annotated with semantic actions for the resulting system to perform its desired function. In this paper, we introduce ModelCC, a model-based parser generator that decouples language specification from language processing, avoiding some of the problems caused by grammar-driven parser generators. ModelCC receives a conceptual model as input, along with constraints that annotate it. It is then able to create a parser for the desired textual syntax and the generated parser fully automates the instantiation of the language conceptual model. ModelCC also includes a reference resolution mechanism so that ModelCC is able to instantiate abstract syntax graphs, rather than mere abstract syntax trees.

Environmental Satellite Models for a Macroeconomic Model

International Nuclear Information System (INIS)

Moeller, F.; Grinderslev, D.; Werner, M.

2003-01-01

To support national environmental policy, it is desirable to forecast and analyse environmental indicators consistently with economic variables. However, environmental indicators are physical measures linked to physical activities that are not specified in economic models. One way to deal with this is to develop environmental satellite models linked to economic models. The system of models presented gives a frame of reference where emissions of greenhouse gases, acid gases, and leaching of nutrients to the aquatic environment are analysed in line with - and consistently with - macroeconomic variables. This paper gives an overview of the data and the satellite models. Finally, the results of applying the model system to calculate the impacts on emissions and the economy are reviewed in a few illustrative examples. The models have been developed for Denmark; however, most of the environmental data used are from the CORINAIR system implemented in numerous countries

A model evaluation checklist for process-based environmental models

Science.gov (United States)

Jackson-Blake, Leah

2015-04-01

Mechanistic catchment-scale phosphorus models appear to perform poorly where diffuse sources dominate. The reasons for this were investigated for one commonly-applied model, the INtegrated model of CAtchment Phosphorus (INCA-P). Model output was compared to 18 months of daily water quality monitoring data in a small agricultural catchment in Scotland, and model structure, key model processes and internal model responses were examined. Although the model broadly reproduced dissolved phosphorus dynamics, it struggled with particulates. The reasons for poor performance were explored, together with ways in which improvements could be made. The process of critiquing and assessing model performance was then generalised to provide a broadly-applicable model evaluation checklist, incorporating: (1) Calibration challenges, relating to difficulties in thoroughly searching a high-dimensional parameter space and in selecting appropriate means of evaluating model performance. In this study, for example, model simplification was identified as a necessary improvement to reduce the number of parameters requiring calibration, whilst the traditionally-used Nash Sutcliffe model performance statistic was not able to discriminate between realistic and unrealistic model simulations, and alternative statistics were needed. (2) Data limitations, relating to a lack of (or uncertainty in) input data, data to constrain model parameters, data for model calibration and testing, and data to test internal model processes. In this study, model reliability could be improved by addressing all four kinds of data limitation. For example, there was insufficient surface water monitoring data for model testing against an independent dataset to that used in calibration, whilst additional monitoring of groundwater and effluent phosphorus inputs would help distinguish between alternative plausible model parameterisations. (3) Model structural inadequacies, whereby model structure may inadequately represent

Coupling Climate Models and Forward-Looking Economic Models

Science.gov (United States)

Judd, K.; Brock, W. A.

2010-12-01

Authors: Dr. Kenneth L. Judd, Hoover Institution, and Prof. William A. Brock, University of Wisconsin Current climate models range from General Circulation Models (GCM’s) with millions of degrees of freedom to models with few degrees of freedom. Simple Energy Balance Climate Models (EBCM’s) help us understand the dynamics of GCM’s. The same is true in economics with Computable General Equilibrium Models (CGE’s) where some models are infinite-dimensional multidimensional differential equations but some are simple models. Nordhaus (2007, 2010) couples a simple EBCM with a simple economic model. One- and two- dimensional ECBM’s do better at approximating damages across the globe and positive and negative feedbacks from anthroprogenic forcing (North etal. (1981), Wu and North (2007)). A proper coupling of climate and economic systems is crucial for arriving at effective policies. Brock and Xepapadeas (2010) have used Fourier/Legendre based expansions to study the shape of socially optimal carbon taxes over time at the planetary level in the face of damages caused by polar ice cap melt (as discussed by Oppenheimer, 2005) but in only a “one dimensional” EBCM. Economists have used orthogonal polynomial expansions to solve dynamic, forward-looking economic models (Judd, 1992, 1998). This presentation will couple EBCM climate models with basic forward-looking economic models, and examine the effectiveness and scaling properties of alternative solution methods. We will use a two dimensional EBCM model on the sphere (Wu and North, 2007) and a multicountry, multisector regional model of the economic system. Our aim will be to gain insights into intertemporal shape of the optimal carbon tax schedule, and its impact on global food production, as modeled by Golub and Hertel (2009). We will initially have limited computing resources and will need to focus on highly aggregated models. However, this will be more complex than existing models with forward

EIA model documentation: Petroleum Market Model of the National Energy Modeling System

Energy Technology Data Exchange (ETDEWEB)

NONE

1994-12-30

The purpose of this report is to define the objectives of the Petroleum Market Model (PMM), describe its basic approach, and provide detail on how it works. This report is intended as a reference document for model analysts, users, and the public. Documentation of the model is in accordance with EIA`s legal obligation to provide adequate documentation in support of its models (Public Law 94-385, section 57.b.2). The PMM models petroleum refining activities, the marketing of products, the production of natural gas liquids and domestic methanol, projects petroleum provides and sources of supplies for meeting demand. In addition, the PMM estimates domestic refinery capacity expansion and fuel consumption.

Recent findings of toxaphene in fish. Analysis and regulation

Energy Technology Data Exchange (ETDEWEB)

Herrmann, T.; Collingro, C.; Paepke, O. [Ergo research, Hamburg (Germany); Dyballa, C. [Chemical and Veterinary Control Lab. (CVUA), Muenster (Germany)

2004-09-15

Toxaphene is a complex mixture of chlorinated camphene derivatives containing 67 to 69 % chlorine. It has been extensively used as an insecticide e.g. for cotton and vegetables, as well as for the control of poultry and livestock ectoparasites. Toxaphene was the active agent in various products with different trademarks often applied in combinations with other organochlorine insecticides. Since 1946 the production of toxaphene is estimated to be more than one million tonsi. Toxaphene is very persistent and has a high potential to accumulate in aquatic life. Various regulations concerning Toxaphene have been set into force. Directive 79/117/EWG prohibits the use and placing on the market of plant protection agencies containing e.g. toxaphene. Toxaphene is a listed contaminant in the UNEP Governing Council Decision 18/32 on Persistent Organic Pollutants. According to the German legislation Rueckstands-Hoechstmengen-VO 2001 (RHmV) the limit value for three toxaphene congeners (total of Parlar 26, Parlar 50 and Parlar 62 -indicator compounds) amounts 0.1 mg/kg fresh weight for fishv. In the beginning of the Nineties the limit value was lower by a factor of 10 (0,01 mg/kg fresh weight), but based on the results from a comprehensive study of the former German Federal Institute for Health Protection of consumers and veterinary medicine (BgVV) and the Federal Research Center for Fisheries, the limit value was increased. In the EU Directive 2002/32/EC a limit value for toxaphene for all kind of feeding stuff, which is 0.1 mg/kg related to a feeding stuff with 12 % moisture content, was set up. This EU regulation does not differentiate between single matrices like the German law does actually. Within the frame of this paper recent findings of toxaphene congeners in fish are presented exemplarily.

Sigma-2 ligands and PARP inhibitors synergistically trigger cell death in breast cancer cells

International Nuclear Information System (INIS)

McDonald, Elizabeth S.; Mankoff, Julia; Makvandi, Mehran; Chu, Wenhua; Chu, Yunxiang; Mach, Robert H.; Zeng, Chenbo

2017-01-01

The sigma-2 receptor is overexpressed in proliferating cells compared to quiescent cells and has been used as a target for imaging solid tumors by positron emission tomography. Recent work has suggested that the sigma-2 receptor may also be an effective therapeutic target for cancer therapy. Poly (ADP-ribose) polymerase (PARP) is a family of enzymes involved in DNA damage response. In this study, we looked for potential synergy of cytotoxicity between PARP inhibitors and sigma-2 receptor ligands in breast cancer cell lines. We showed that the PARP inhibitor, YUN3-6, sensitized mouse breast cancer cell line, EMT6, to sigma-2 receptor ligand (SV119, WC-26, and RHM-138) induced cell death determined by cell viability assay and colony forming assay. The PARP inhibitor, olaparib, sensitized tumor cells to a different sigma-2 receptor ligand SW43-induced apoptosis and cell death in human triple negative cell line, MDA-MB-231. Olaparib inhibited PARP activity and cell proliferation, and arrested cells in G2/M phase of the cell cycle in MDA-MB-231 cells. Subsequently cells became sensitized to SW43 induced cell death. In conclusion, the combination of sigma-2 receptor ligands and PARP inhibitors appears to hold promise for synergistically triggering cell death in certain types of breast cancer cells and merits further investigation. - Highlights: • PARPi, YUN3-6 and olaparib, and σ2 ligands, SV119 and SW43, were evaluated. • Mouse and human breast cancer cells, EMT6 and MDA-MB-231 respectively, were used. • YUN3-6 and SV119 synergistically triggered cell death in EMT6 cells. • Olaparib and SW43 additively triggered cell death in MDA-MB-231 cells. • Olaparib arrested cells in G2/M in MDA-MB-231 cells.

Sustainable prevention of resource conflicts. Case studies and scenarios for the Nabucco pipeline (report 3.1); Rohstoffkonflikte nachhaltig vermeiden. Fallstudie und Szenarien zur Nabucco-Pipeline (Teilbericht 3.1)

Energy Technology Data Exchange (ETDEWEB)

Taenzler, Dennis; Westerkamp, Meike [Adelphi Research, Berlin (Germany); Supersberger, Nikolaus; Ritthoff, Michael; Bleischwitz, Raimund [Wuppertal Institut (Germany)

2011-04-15

The controversial discussion over natural gas supply in Europe has been going on for several years now; it all started with the controversy between Russia, Europe's main supplier country, and Ukraine and Belorus. The wish to reduce the dependence on Russian imports resulted in several European projects. One of them is the so-called Nabucco pipeline, which will transport natural gas from the Caspian region to Western Europe without touching Russian territory. A comprehensive view of the case study and the scenarios derived from it shows that the supply and demand situation in the European Union will be the central element of all developments. The economic efficiency of the Nabucco pipeline will depend on the implementation of efficiency strategies within the EU. In case of peak gas production, it is difficult to see how the Nabucco pipeline will be affected; it will depend largely on the regions in which natural gas production will decline the most. Cooperative regimes may develop along the Nabucco pipeline if the pipeline is viewed not only as an economic project but also as an approach to getting many actors together with maximum benefit to all. For the EU itself, the Nabucco pipeline is an important instrument for reducing dependence on Russian natural gas. However, Nabucco will compete with the NordStream pipeline that is currently being laid through the Baltic Sea. The NordStream pipeline is contraproductive in that it increases dependence on Russian natural gas. At the same time, the existing energy partnership between the EU and Russia is to be deepened. In principle, the Nabucco pipeline is a relevant approach to avoiding possible supply and dependence conflicts on a transnational level. (orig./RHM)

Accuracy of the DLPNO-CCSD(T) method for non-covalent bond dissociation enthalpies from coinage metal cation complexes

KAUST Repository

Minenkov, Yury; Chermak, Edrisse; Cavallo, Luigi

2015-01-01

The performance of the domain based local pair-natural orbital coupled-cluster (DLPNO-CCSD(T)) method has been tested to reproduce the experimental gas phase ligand dissociation enthalpy in a series of Cu+, Ag+ and Au+ complexes. For 33 Cu+ - non-covalent ligand dissociation enthalpies all-electron calculations with the same method result in MUE below 2.2 kcal/mol, although a MSE of 1.4 kcal/mol indicates systematic underestimation of the experimental values. Inclusion of scalar relativistic effects for Cu either via effective core potential (ECP) or Douglass-Kroll-Hess Hamiltonian, reduces the MUE below 1.7 kcal/mol and the MSE to -1.0 kcal/mol. For 24 Ag+ - non-covalent ligand dissociation enthalpies the DLPNO-CCSD(T) method results in a mean unsigned error (MUE) below 2.1 kcal/mol and vanishing mean signed error (MSE). For 15 Au+ - non-covalent ligand dissociation enthalpies the DLPNO-CCSD(T) methods provides larger MUE and MSE, equal to 3.2 and 1.7 kcal/mol, which might be related to poor precision of the experimental measurements. Overall, for the combined dataset of 72 coinage metal ion complexes DLPNO-CCSD(T) results in a MUE below 2.2 kcal/mol and an almost vanishing MSE. As for a comparison with computationally cheaper density functional theory (DFT) methods, the routinely used M06 functional results in MUE and MSE equal to 3.6 and -1.7 kca/mol. Results converge already at CC-PVTZ quality basis set, making highly accurate DLPNO-CCSD(T) estimates to be affordable for routine calculations (single-point) on large transition metal complexes of > 100 atoms.

Estimation of ΔR/R values by benchmark study of the Mössbauer Isomer shifts for Ru, Os complexes using relativistic DFT calculations

Energy Technology Data Exchange (ETDEWEB)

Kaneko, Masashi [Japan Atomic Energy Agency, Nuclear Science and Engineering Center (Japan); Yasuhara, Hiroki; Miyashita, Sunao; Nakashima, Satoru, E-mail: snaka@hiroshima-u.ac.jp [Hiroshima University, Graduate School of Science (Japan)

2017-11-15

The present study applies all-electron relativistic DFT calculation with Douglas-Kroll-Hess (DKH) Hamiltonian to each ten sets of Ru and Os compounds. We perform the benchmark investigation of three density functionals (BP86, B3LYP and B2PLYP) using segmented all-electron relativistically contracted (SARC) basis set with the experimental Mössbauer isomer shifts for {sup 99}Ru and {sup 189}Os nuclides. Geometry optimizations at BP86 theory of level locate the structure in a local minimum. We calculate the contact density to the wavefunction obtained by a single point calculation. All functionals show the good linear correlation with experimental isomer shifts for both {sup 99}Ru and {sup 189}Os. Especially, B3LYP functional gives a stronger correlation compared to BP86 and B2PLYP functionals. The comparison of contact density between SARC and well-tempered basis set (WTBS) indicated that the numerical convergence of contact density cannot be obtained, but the reproducibility is less sensitive to the choice of basis set. We also estimate the values of ΔR/R, which is an important nuclear constant, for {sup 99}Ru and {sup 189}Os nuclides by using the benchmark results. The sign of the calculated ΔR/R values is consistent with the predicted data for {sup 99}Ru and {sup 189}Os. We obtain computationally the ΔR/R values of {sup 99}Ru and {sup 189}Os (36.2 keV) as 2.35×10{sup −4} and −0.20×10{sup −4}, respectively, at B3LYP level for SARC basis set.

The electronic structure of vanadium monochloride cation (VCl+): Tackling the complexities of transition metal species

Science.gov (United States)

DeYonker, Nathan J.; Halfen, DeWayne T.; Allen, Wesley D.; Ziurys, Lucy M.

2014-11-01

Six electronic states (X 4Σ-, A 4Π, B 4Δ, 2Φ, 2Δ, 2Σ+) of the vanadium monochloride cation (VCl+) are described using large basis set coupled cluster theory. For the two lowest quartet states (X 4Σ- and A 4Π), a focal point analysis (FPA) approach was used that conjoined a correlation-consistent family of basis sets up to aug-cc-pwCV5Z-DK with high-order coupled cluster theory through pentuple (CCSDTQP) excitations. FPA adiabatic excitation energies (T0) and spectroscopic constants (re, r0, Be, B0, bar De, He, ωe, v0, αe, ωexe) were extrapolated to the valence complete basis set Douglas-Kroll (DK) aug-cc-pV∞Z-DK CCSDT level of theory, and additional treatments accounted for higher-order valence electron correlation, core correlation, and spin-orbit coupling. Due to the delicate interplay between dynamical and static electronic correlation, single reference coupled cluster theory is able to provide the correct ground electronic state (X 4Σ-), while multireference configuration interaction theory cannot. Perturbations from the first- and second-order spin orbit coupling of low-lying states with quartet spin multiplicity reveal an immensely complex rotational spectrum relative to the isovalent species VO, VS, and TiCl. Computational data on the doublet manifold suggest that the lowest-lying doublet state (2Γ) has a Te of ˜11 200 cm-1. Overall, this study shows that laboratory and theoretical rotational spectroscopists must work more closely in tandem to better understand the bonding and structure of molecules containing transition metals.

Permeability Changes Observed in the Arbuckle Group Coincident with Nearby Earthquake Occurrence

Science.gov (United States)

Kroll, K.; Cochran, E. S.; Richards-Dinger, K. B.; Murray, K.

2017-12-01

We investigate the temporal evolution of hydrologic properties of the 2 km deep Arbuckle Group, the principal target in Oklahoma for saltwater disposal resulting from oil and gas production. Specifically, we look for changes to the hydrologic system associated with local earthquakes at two monitoring wells (Payne07 and 08) near Cushing, Oklahoma. The wells were instrumented with pressure transducers starting in Aug. 2016, after injection was discontinued due to regulatory directives. The observation period includes the 3 Sep 2016 Mw5.8 Pawnee and 7 Nov. 2016 Mw5.0 Cushing earthquakes located 50 km and 5 km from the wells, respectively. Previous studies have suggested the Mw5.8 Pawnee earthquake affected both the shallow and deep hydrological systems, with an increase in stream discharge observed near the mainshock (Manga et al., 2016) and a change in poroelastic properties of the Arbuckle inferred from the observed co-seismic water level offsets observed at Payne 07 and 08 (Kroll et al., 2017). Here, we use the water level response to solid Earth tides to estimate permeability and specific storage through time during the observation period. We measure the phase lag between the solid Earth tide and the water level changes and find that phase lag between the Earth tide and aquifer response decreases at the time of the Mw5.0 Cushing earthquake in both wells. Our results suggest permeability increased in the Arbuckle Group after the earthquake by a factor of 5. It is possible that in extreme cases there may be complex interaction between saltwater disposal, hydrologic systems, and earthquake rates that should be considered to better understand seismic hazard.

Accuracy of the DLPNO-CCSD(T) method for non-covalent bond dissociation enthalpies from coinage metal cation complexes

KAUST Repository

Minenkov, Yury

2015-08-27

The performance of the domain based local pair-natural orbital coupled-cluster (DLPNO-CCSD(T)) method has been tested to reproduce the experimental gas phase ligand dissociation enthalpy in a series of Cu+, Ag+ and Au+ complexes. For 33 Cu+ - non-covalent ligand dissociation enthalpies all-electron calculations with the same method result in MUE below 2.2 kcal/mol, although a MSE of 1.4 kcal/mol indicates systematic underestimation of the experimental values. Inclusion of scalar relativistic effects for Cu either via effective core potential (ECP) or Douglass-Kroll-Hess Hamiltonian, reduces the MUE below 1.7 kcal/mol and the MSE to -1.0 kcal/mol. For 24 Ag+ - non-covalent ligand dissociation enthalpies the DLPNO-CCSD(T) method results in a mean unsigned error (MUE) below 2.1 kcal/mol and vanishing mean signed error (MSE). For 15 Au+ - non-covalent ligand dissociation enthalpies the DLPNO-CCSD(T) methods provides larger MUE and MSE, equal to 3.2 and 1.7 kcal/mol, which might be related to poor precision of the experimental measurements. Overall, for the combined dataset of 72 coinage metal ion complexes DLPNO-CCSD(T) results in a MUE below 2.2 kcal/mol and an almost vanishing MSE. As for a comparison with computationally cheaper density functional theory (DFT) methods, the routinely used M06 functional results in MUE and MSE equal to 3.6 and -1.7 kca/mol. Results converge already at CC-PVTZ quality basis set, making highly accurate DLPNO-CCSD(T) estimates to be affordable for routine calculations (single-point) on large transition metal complexes of > 100 atoms.

Modeling Methods

Science.gov (United States)

Healy, Richard W.; Scanlon, Bridget R.

2010-01-01

Simulation models are widely used in all types of hydrologic studies, and many of these models can be used to estimate recharge. Models can provide important insight into the functioning of hydrologic systems by identifying factors that influence recharge. The predictive capability of models can be used to evaluate how changes in climate, water use, land use, and other factors may affect recharge rates. Most hydrological simulation models, including watershed models and groundwater-flow models, are based on some form of water-budget equation, so the material in this chapter is closely linked to that in Chapter 2. Empirical models that are not based on a water-budget equation have also been used for estimating recharge; these models generally take the form of simple estimation equations that define annual recharge as a function of precipitation and possibly other climatic data or watershed characteristics.Model complexity varies greatly. Some models are simple accounting models; others attempt to accurately represent the physics of water movement through each compartment of the hydrologic system. Some models provide estimates of recharge explicitly; for example, a model based on the Richards equation can simulate water movement from the soil surface through the unsaturated zone to the water table. Recharge estimates can be obtained indirectly from other models. For example, recharge is a parameter in groundwater-flow models that solve for hydraulic head (i.e. groundwater level). Recharge estimates can be obtained through a model calibration process in which recharge and other model parameter values are adjusted so that simulated water levels agree with measured water levels. The simulation that provides the closest agreement is called the best fit, and the recharge value used in that simulation is the model-generated estimate of recharge.

Post-model selection inference and model averaging

Directory of Open Access Journals (Sweden)

Georges Nguefack-Tsague

2011-07-01

Full Text Available Although model selection is routinely used in practice nowadays, little is known about its precise effects on any subsequent inference that is carried out. The same goes for the effects induced by the closely related technique of model averaging. This paper is concerned with the use of the same data first to select a model and then to carry out inference, in particular point estimation and point prediction. The properties of the resulting estimator, called a post-model-selection estimator (PMSE, are hard to derive. Using selection criteria such as hypothesis testing, AIC, BIC, HQ and Cp, we illustrate that, in terms of risk function, no single PMSE dominates the others. The same conclusion holds more generally for any penalised likelihood information criterion. We also compare various model averaging schemes and show that no single one dominates the others in terms of risk function. Since PMSEs can be regarded as a special case of model averaging, with 0-1 random-weights, we propose a connection between the two theories, in the frequentist approach, by taking account of the selection procedure when performing model averaging. We illustrate the point by simulating a simple linear regression model.

The DINA model as a constrained general diagnostic model: Two variants of a model equivalency.

Science.gov (United States)

von Davier, Matthias

2014-02-01

The 'deterministic-input noisy-AND' (DINA) model is one of the more frequently applied diagnostic classification models for binary observed responses and binary latent variables. The purpose of this paper is to show that the model is equivalent to a special case of a more general compensatory family of diagnostic models. Two equivalencies are presented. Both project the original DINA skill space and design Q-matrix using mappings into a transformed skill space as well as a transformed Q-matrix space. Both variants of the equivalency produce a compensatory model that is mathematically equivalent to the (conjunctive) DINA model. This equivalency holds for all DINA models with any type of Q-matrix, not only for trivial (simple-structure) cases. The two versions of the equivalency presented in this paper are not implied by the recently suggested log-linear cognitive diagnosis model or the generalized DINA approach. The equivalencies presented here exist independent of these recently derived models since they solely require a linear - compensatory - general diagnostic model without any skill interaction terms. Whenever it can be shown that one model can be viewed as a special case of another more general one, conclusions derived from any particular model-based estimates are drawn into question. It is widely known that multidimensional models can often be specified in multiple ways while the model-based probabilities of observed variables stay the same. This paper goes beyond this type of equivalency by showing that a conjunctive diagnostic classification model can be expressed as a constrained special case of a general compensatory diagnostic modelling framework. © 2013 The British Psychological Society.

Performance Measurement Model A TarBase model with ...

Indian Academy of Sciences (India)

rohit

Model A 8.0 2.0 94.52% 88.46% 76 108 12 12 0.86 0.91 0.78 0.94. Model B 2.0 2.0 93.18% 89.33% 64 95 10 9 0.88 0.90 0.75 0.98. The above results for TEST – 1 show details for our two models (Model A and Model B).Performance of Model A after adding of 32 negative dataset of MiRTif on our testing set(MiRecords) ...

Underground economy modelling: simple models with complicated dynamics

OpenAIRE

Albu, Lucian-Liviu

2003-01-01

The paper aims to model the underground economy using two different models: one based on the labor supply method and a generalized model for the allocation of time. The model based on the labor supply method is conceived as a simulating one in order to determine some reasonable thresholds of the underground sector extension based only on the available macroeconomic statistical data. The generalized model for the allocation of time is a model based on direct approach which estimates the underg...

Integrative structure modeling with the Integrative Modeling Platform.

Science.gov (United States)

Webb, Benjamin; Viswanath, Shruthi; Bonomi, Massimiliano; Pellarin, Riccardo; Greenberg, Charles H; Saltzberg, Daniel; Sali, Andrej

2018-01-01

Building models of a biological system that are consistent with the myriad data available is one of the key challenges in biology. Modeling the structure and dynamics of macromolecular assemblies, for example, can give insights into how biological systems work, evolved, might be controlled, and even designed. Integrative structure modeling casts the building of structural models as a computational optimization problem, for which information about the assembly is encoded into a scoring function that evaluates candidate models. Here, we describe our open source software suite for integrative structure modeling, Integrative Modeling Platform (https://integrativemodeling.org), and demonstrate its use. © 2017 The Protein Society.

Modeling volatility using state space models.

Science.gov (United States)

Timmer, J; Weigend, A S

1997-08-01

In time series problems, noise can be divided into two categories: dynamic noise which drives the process, and observational noise which is added in the measurement process, but does not influence future values of the system. In this framework, we show that empirical volatilities (the squared relative returns of prices) exhibit a significant amount of observational noise. To model and predict their time evolution adequately, we estimate state space models that explicitly include observational noise. We obtain relaxation times for shocks in the logarithm of volatility ranging from three weeks (for foreign exchange) to three to five months (for stock indices). In most cases, a two-dimensional hidden state is required to yield residuals that are consistent with white noise. We compare these results with ordinary autoregressive models (without a hidden state) and find that autoregressive models underestimate the relaxation times by about two orders of magnitude since they do not distinguish between observational and dynamic noise. This new interpretation of the dynamics of volatility in terms of relaxators in a state space model carries over to stochastic volatility models and to GARCH models, and is useful for several problems in finance, including risk management and the pricing of derivative securities. Data sets used: Olsen & Associates high frequency DEM/USD foreign exchange rates (8 years). Nikkei 225 index (40 years). Dow Jones Industrial Average (25 years).

Document Models

Directory of Open Access Journals (Sweden)

A.A. Malykh

2017-08-01

Full Text Available In this paper, the concept of locally simple models is considered. Locally simple models are arbitrarily complex models built from relatively simple components. A lot of practically important domains of discourse can be described as locally simple models, for example, business models of enterprises and companies. Up to now, research in human reasoning automation has been mainly concentrated around the most intellectually intensive activities, such as automated theorem proving. On the other hand, the retailer business model is formed from ”jobs”, and each ”job” can be modelled and automated more or less easily. At the same time, the whole retailer model as an integrated system is extremely complex. In this paper, we offer a variant of the mathematical definition of a locally simple model. This definition is intended for modelling a wide range of domains. Therefore, we also must take into account the perceptual and psychological issues. Logic is elitist, and if we want to attract to our models as many people as possible, we need to hide this elitism behind some metaphor, to which ’ordinary’ people are accustomed. As such a metaphor, we use the concept of a document, so our locally simple models are called document models. Document models are built in the paradigm of semantic programming. This allows us to achieve another important goal - to make the documentary models executable. Executable models are models that can act as practical information systems in the described domain of discourse. Thus, if our model is executable, then programming becomes redundant. The direct use of a model, instead of its programming coding, brings important advantages, for example, a drastic cost reduction for development and maintenance. Moreover, since the model is well and sound, and not dissolved within programming modules, we can directly apply AI tools, in particular, machine learning. This significantly expands the possibilities for automation and

An online model composition tool for system biology models.

Science.gov (United States)

Coskun, Sarp A; Cicek, A Ercument; Lai, Nicola; Dash, Ranjan K; Ozsoyoglu, Z Meral; Ozsoyoglu, Gultekin

2013-09-05

There are multiple representation formats for Systems Biology computational models, and the Systems Biology Markup Language (SBML) is one of the most widely used. SBML is used to capture, store, and distribute computational models by Systems Biology data sources (e.g., the BioModels Database) and researchers. Therefore, there is a need for all-in-one web-based solutions that support advance SBML functionalities such as uploading, editing, composing, visualizing, simulating, querying, and browsing computational models. We present the design and implementation of the Model Composition Tool (Interface) within the PathCase-SB (PathCase Systems Biology) web portal. The tool helps users compose systems biology models to facilitate the complex process of merging systems biology models. We also present three tools that support the model composition tool, namely, (1) Model Simulation Interface that generates a visual plot of the simulation according to user's input, (2) iModel Tool as a platform for users to upload their own models to compose, and (3) SimCom Tool that provides a side by side comparison of models being composed in the same pathway. Finally, we provide a web site that hosts BioModels Database models and a separate web site that hosts SBML Test Suite models. Model composition tool (and the other three tools) can be used with little or no knowledge of the SBML document structure. For this reason, students or anyone who wants to learn about systems biology will benefit from the described functionalities. SBML Test Suite models will be a nice starting point for beginners. And, for more advanced purposes, users will able to access and employ models of the BioModels Database as well.

Modeling inputs to computer models used in risk assessment

International Nuclear Information System (INIS)

Iman, R.L.

1987-01-01

Computer models for various risk assessment applications are closely scrutinized both from the standpoint of questioning the correctness of the underlying mathematical model with respect to the process it is attempting to model and from the standpoint of verifying that the computer model correctly implements the underlying mathematical model. A process that receives less scrutiny, but is nonetheless of equal importance, concerns the individual and joint modeling of the inputs. This modeling effort clearly has a great impact on the credibility of results. Model characteristics are reviewed in this paper that have a direct bearing on the model input process and reasons are given for using probabilities-based modeling with the inputs. The authors also present ways to model distributions for individual inputs and multivariate input structures when dependence and other constraints may be present

A Model of Trusted Measurement Model

OpenAIRE

Ma Zhili; Wang Zhihao; Dai Liang; Zhu Xiaoqin

2017-01-01

A model of Trusted Measurement supporting behavior measurement based on trusted connection architecture (TCA) with three entities and three levels is proposed, and a frame to illustrate the model is given. The model synthesizes three trusted measurement dimensions including trusted identity, trusted status and trusted behavior, satisfies the essential requirements of trusted measurement, and unified the TCA with three entities and three levels.

A unification of RDE model and XCDM model

International Nuclear Information System (INIS)

Liao, Kai; Zhu, Zong-Hong

2013-01-01

In this Letter, we propose a new generalized Ricci dark energy (NGR) model to unify Ricci dark energy (RDE) and XCDM. Our model can distinguish between RDE and XCDM by introducing a parameter β called weight factor. When β=1, NGR model becomes the usual RDE model. The XCDM model is corresponding to β=0. Moreover, NGR model permits the situation where neither β=1 nor β=0. We then perform a statefinder analysis on NGR model to see how β effects the trajectory on the r–s plane. In order to know the value of β, we constrain NGR model with latest observations including type Ia supernovae (SNe Ia) from Union2 set (557 data), baryonic acoustic oscillation (BAO) observation from the spectroscopic Sloan Digital Sky Survey (SDSS) data release 7 (DR7) galaxy sample and cosmic microwave background (CMB) observation from the 7-year Wilkinson Microwave Anisotropy Probe (WMAP7) results. With Markov Chain Monte Carlo (MCMC) method, the constraint result is β=0.08 −0.21 +0.30 (1σ) −0.28 +0.43 (2σ), which manifests the observations prefer a XCDM universe rather than RDE model. It seems RDE model is ruled out in NGR scenario within 2σ regions. Furthermore, we compare it with some of successful cosmological models using AIC information criterion. NGR model seems to be a good choice for describing the universe.

Downscaling GISS ModelE Boreal Summer Climate over Africa

Science.gov (United States)

Druyan, Leonard M.; Fulakeza, Matthew

2015-01-01

The study examines the perceived added value of downscaling atmosphere-ocean global climate model simulations over Africa and adjacent oceans by a nested regional climate model. NASA/Goddard Institute for Space Studies (GISS) coupled ModelE simulations for June- September 1998-2002 are used to form lateral boundary conditions for synchronous simulations by the GISS RM3 regional climate model. The ModelE computational grid spacing is 2deg latitude by 2.5deg longitude and the RM3 grid spacing is 0.44deg. ModelE precipitation climatology for June-September 1998-2002 is shown to be a good proxy for 30-year means so results based on the 5-year sample are presumed to be generally representative. Comparison with observational evidence shows several discrepancies in ModelE configuration of the boreal summer inter-tropical convergence zone (ITCZ). One glaring shortcoming is that ModelE simulations do not advance the West African rain band northward during the summer to represent monsoon precipitation onset over the Sahel. Results for 1998-2002 show that onset simulation is an important added value produced by downscaling with RM3. ModelE Eastern South Atlantic Ocean computed sea-surface temperatures (SST) are some 4 K warmer than reanalysis, contributing to large positive biases in overlying surface air temperatures (Tsfc). ModelE Tsfc are also too warm over most of Africa. RM3 downscaling somewhat mitigates the magnitude of Tsfc biases over the African continent, it eliminates the ModelE double ITCZ over the Atlantic and it produces more realistic orographic precipitation maxima. Parallel ModelE and RM3 simulations with observed SST forcing (in place of the predicted ocean) lower Tsfc errors but have mixed impacts on circulation and precipitation biases. Downscaling improvements of the meridional movement of the rain band over West Africa and the configuration of orographic precipitation maxima are realized irrespective of the SST biases.

Essays on model uncertainty in financial models

NARCIS (Netherlands)

Li, Jing

2018-01-01

This dissertation studies model uncertainty, particularly in financial models. It consists of two empirical chapters and one theoretical chapter. The first empirical chapter (Chapter 2) classifies model uncertainty into parameter uncertainty and misspecification uncertainty. It investigates the

Mixed models for predictive modeling in actuarial science

NARCIS (Netherlands)

Antonio, K.; Zhang, Y.

2012-01-01

We start with a general discussion of mixed (also called multilevel) models and continue with illustrating specific (actuarial) applications of this type of models. Technical details on (linear, generalized, non-linear) mixed models follow: model assumptions, specifications, estimation techniques

ModelMate - A graphical user interface for model analysis

Science.gov (United States)

Banta, Edward R.

2011-01-01

ModelMate is a graphical user interface designed to facilitate use of model-analysis programs with models. This initial version of ModelMate supports one model-analysis program, UCODE_2005, and one model software program, MODFLOW-2005. ModelMate can be used to prepare input files for UCODE_2005, run UCODE_2005, and display analysis results. A link to the GW_Chart graphing program facilitates visual interpretation of results. ModelMate includes capabilities for organizing directories used with the parallel-processing capabilities of UCODE_2005 and for maintaining files in those directories to be identical to a set of files in a master directory. ModelMate can be used on its own or in conjunction with ModelMuse, a graphical user interface for MODFLOW-2005 and PHAST.

Reactor core modeling practice: Operational requirements, model characteristics, and model validation

International Nuclear Information System (INIS)

Zerbino, H.

1997-01-01

The physical models implemented in power plant simulators have greatly increased in performance and complexity in recent years. This process has been enabled by the ever increasing computing power available at affordable prices. This paper describes this process from several angles: First the operational requirements which are more critical from the point of view of model performance, both for normal and off-normal operating conditions; A second section discusses core model characteristics in the light of the solutions implemented by Thomson Training and Simulation (TT and S) in several full-scope simulators recently built and delivered for Dutch, German, and French nuclear power plants; finally we consider the model validation procedures, which are of course an integral part of model development, and which are becoming more and more severe as performance expectations increase. As a conclusion, it may be asserted that in the core modeling field, as in other areas, the general improvement in the quality of simulation codes has resulted in a fairly rapid convergence towards mainstream engineering-grade calculations. This is remarkable performance in view of the stringent real-time requirements which the simulation codes must satisfy as well as the extremely wide range of operating conditions that they are called upon to cover with good accuracy. (author)

Mineralogic Model (MM3.0) Analysis Model Report

Energy Technology Data Exchange (ETDEWEB)

C. Lum

2002-02-12

The purpose of this report is to document the Mineralogic Model (MM), Version 3.0 (MM3.0) with regard to data input, modeling methods, assumptions, uncertainties, limitations and validation of the model results, qualification status of the model, and the differences between Version 3.0 and previous versions. A three-dimensional (3-D) Mineralogic Model was developed for Yucca Mountain to support the analyses of hydrologic properties, radionuclide transport, mineral health hazards, repository performance, and repository design. Version 3.0 of the MM was developed from mineralogic data obtained from borehole samples. It consists of matrix mineral abundances as a function of x (easting), y (northing), and z (elevation), referenced to the stratigraphic framework defined in Version 3.1 of the Geologic Framework Model (GFM). The MM was developed specifically for incorporation into the 3-D Integrated Site Model (ISM). The MM enables project personnel to obtain calculated mineral abundances at any position, within any region, or within any stratigraphic unit in the model area. The significance of the MM for key aspects of site characterization and performance assessment is explained in the following subsections. This work was conducted in accordance with the Development Plan for the MM (CRWMS M&O 2000). The planning document for this Rev. 00, ICN 02 of this AMR is Technical Work Plan, TWP-NBS-GS-000003, Technical Work Plan for the Integrated Site Model, Process Model Report, Revision 01 (CRWMS M&O 2000). The purpose of this ICN is to record changes in the classification of input status by the resolution of the use of TBV software and data in this report. Constraints and limitations of the MM are discussed in the appropriate sections that follow. The MM is one component of the ISM, which has been developed to provide a consistent volumetric portrayal of the rock layers, rock properties, and mineralogy of the Yucca Mountain site. The ISM consists of three components: (1

Mineralogic Model (MM3.0) Analysis Model Report

International Nuclear Information System (INIS)

Lum, C.

2002-01-01

The purpose of this report is to document the Mineralogic Model (MM), Version 3.0 (MM3.0) with regard to data input, modeling methods, assumptions, uncertainties, limitations and validation of the model results, qualification status of the model, and the differences between Version 3.0 and previous versions. A three-dimensional (3-D) Mineralogic Model was developed for Yucca Mountain to support the analyses of hydrologic properties, radionuclide transport, mineral health hazards, repository performance, and repository design. Version 3.0 of the MM was developed from mineralogic data obtained from borehole samples. It consists of matrix mineral abundances as a function of x (easting), y (northing), and z (elevation), referenced to the stratigraphic framework defined in Version 3.1 of the Geologic Framework Model (GFM). The MM was developed specifically for incorporation into the 3-D Integrated Site Model (ISM). The MM enables project personnel to obtain calculated mineral abundances at any position, within any region, or within any stratigraphic unit in the model area. The significance of the MM for key aspects of site characterization and performance assessment is explained in the following subsections. This work was conducted in accordance with the Development Plan for the MM (CRWMS M and O 2000). The planning document for this Rev. 00, ICN 02 of this AMR is Technical Work Plan, TWP-NBS-GS-000003, Technical Work Plan for the Integrated Site Model, Process Model Report, Revision 01 (CRWMS M and O 2000). The purpose of this ICN is to record changes in the classification of input status by the resolution of the use of TBV software and data in this report. Constraints and limitations of the MM are discussed in the appropriate sections that follow. The MM is one component of the ISM, which has been developed to provide a consistent volumetric portrayal of the rock layers, rock properties, and mineralogy of the Yucca Mountain site. The ISM consists of three components

ERM model analysis for adaptation to hydrological model errors

Science.gov (United States)

Baymani-Nezhad, M.; Han, D.

2018-05-01

Hydrological conditions are changed continuously and these phenomenons generate errors on flood forecasting models and will lead to get unrealistic results. Therefore, to overcome these difficulties, a concept called model updating is proposed in hydrological studies. Real-time model updating is one of the challenging processes in hydrological sciences and has not been entirely solved due to lack of knowledge about the future state of the catchment under study. Basically, in terms of flood forecasting process, errors propagated from the rainfall-runoff model are enumerated as the main source of uncertainty in the forecasting model. Hence, to dominate the exciting errors, several methods have been proposed by researchers to update the rainfall-runoff models such as parameter updating, model state updating, and correction on input data. The current study focuses on investigations about the ability of rainfall-runoff model parameters to cope with three types of existing errors, timing, shape and volume as the common errors in hydrological modelling. The new lumped model, the ERM model, has been selected for this study to evaluate its parameters for its use in model updating to cope with the stated errors. Investigation about ten events proves that the ERM model parameters can be updated to cope with the errors without the need to recalibrate the model.

Model documentation report: Short-Term Hydroelectric Generation Model

International Nuclear Information System (INIS)

1993-08-01

The purpose of this report is to define the objectives of the Short- Term Hydroelectric Generation Model (STHGM), describe its basic approach, and to provide details on the model structure. This report is intended as a reference document for model analysts, users, and the general public. Documentation of the model is in accordance with the Energy Information Administration's (AYE) legal obligation to provide adequate documentation in support of its models (Public Law 94-385, Section 57.b.2). The STHGM performs a short-term (18 to 27- month) forecast of hydroelectric generation in the United States using an autoregressive integrated moving average (UREMIA) time series model with precipitation as an explanatory variable. The model results are used as input for the short-term Energy Outlook

Geochemistry Model Validation Report: External Accumulation Model

International Nuclear Information System (INIS)

Zarrabi, K.

2001-01-01

The purpose of this Analysis and Modeling Report (AMR) is to validate the External Accumulation Model that predicts accumulation of fissile materials in fractures and lithophysae in the rock beneath a degrading waste package (WP) in the potential monitored geologic repository at Yucca Mountain. (Lithophysae are voids in the rock having concentric shells of finely crystalline alkali feldspar, quartz, and other materials that were formed due to entrapped gas that later escaped, DOE 1998, p. A-25.) The intended use of this model is to estimate the quantities of external accumulation of fissile material for use in external criticality risk assessments for different types of degrading WPs: U.S. Department of Energy (DOE) Spent Nuclear Fuel (SNF) codisposed with High Level Waste (HLW) glass, commercial SNF, and Immobilized Plutonium Ceramic (Pu-ceramic) codisposed with HLW glass. The scope of the model validation is to (1) describe the model and the parameters used to develop the model, (2) provide rationale for selection of the parameters by comparisons with measured values, and (3) demonstrate that the parameters chosen are the most conservative selection for external criticality risk calculations. To demonstrate the applicability of the model, a Pu-ceramic WP is used as an example. The model begins with a source term from separately documented EQ6 calculations; where the source term is defined as the composition versus time of the water flowing out of a breached waste package (WP). Next, PHREEQC, is used to simulate the transport and interaction of the source term with the resident water and fractured tuff below the repository. In these simulations the primary mechanism for accumulation is mixing of the high pH, actinide-laden source term with resident water; thus lowering the pH values sufficiently for fissile minerals to become insoluble and precipitate. In the final section of the model, the outputs from PHREEQC, are processed to produce mass of accumulation

Model uncertainty: Probabilities for models?

International Nuclear Information System (INIS)

Winkler, R.L.

1994-01-01

Like any other type of uncertainty, model uncertainty should be treated in terms of probabilities. The question is how to do this. The most commonly-used approach has a drawback related to the interpretation of the probabilities assigned to the models. If we step back and look at the big picture, asking what the appropriate focus of the model uncertainty question should be in the context of risk and decision analysis, we see that a different probabilistic approach makes more sense, although it raise some implementation questions. Current work that is underway to address these questions looks very promising

Model evaluation methodology applicable to environmental assessment models

International Nuclear Information System (INIS)

Shaeffer, D.L.

1979-08-01

A model evaluation methodology is presented to provide a systematic framework within which the adequacy of environmental assessment models might be examined. The necessity for such a tool is motivated by the widespread use of models for predicting the environmental consequences of various human activities and by the reliance on these model predictions for deciding whether a particular activity requires the deployment of costly control measures. Consequently, the uncertainty associated with prediction must be established for the use of such models. The methodology presented here consists of six major tasks: model examination, algorithm examination, data evaluation, sensitivity analyses, validation studies, and code comparison. This methodology is presented in the form of a flowchart to show the logical interrelatedness of the various tasks. Emphasis has been placed on identifying those parameters which are most important in determining the predictive outputs of a model. Importance has been attached to the process of collecting quality data. A method has been developed for analyzing multiplicative chain models when the input parameters are statistically independent and lognormally distributed. Latin hypercube sampling has been offered as a promising candidate for doing sensitivity analyses. Several different ways of viewing the validity of a model have been presented. Criteria are presented for selecting models for environmental assessment purposes

Galactic models

International Nuclear Information System (INIS)

Buchler, J.R.; Gottesman, S.T.; Hunter, J.H. Jr.

1990-01-01

Various papers on galactic models are presented. Individual topics addressed include: observations relating to galactic mass distributions; the structure of the Galaxy; mass distribution in spiral galaxies; rotation curves of spiral galaxies in clusters; grand design, multiple arm, and flocculent spiral galaxies; observations of barred spirals; ringed galaxies; elliptical galaxies; the modal approach to models of galaxies; self-consistent models of spiral galaxies; dynamical models of spiral galaxies; N-body models. Also discussed are: two-component models of galaxies; simulations of cloudy, gaseous galactic disks; numerical experiments on the stability of hot stellar systems; instabilities of slowly rotating galaxies; spiral structure as a recurrent instability; model gas flows in selected barred spiral galaxies; bar shapes and orbital stochasticity; three-dimensional models; polar ring galaxies; dynamical models of polar rings

A Model-Model and Data-Model Comparison for the Early Eocene Hydrological Cycle

Science.gov (United States)

Carmichael, Matthew J.; Lunt, Daniel J.; Huber, Matthew; Heinemann, Malte; Kiehl, Jeffrey; LeGrande, Allegra; Loptson, Claire A.; Roberts, Chris D.; Sagoo, Navjit; Shields, Christine

2016-01-01

A range of proxy observations have recently provided constraints on how Earth's hydrological cycle responded to early Eocene climatic changes. However, comparisons of proxy data to general circulation model (GCM) simulated hydrology are limited and inter-model variability remains poorly characterised. In this work, we undertake an intercomparison of GCM-derived precipitation and P - E distributions within the extended EoMIP ensemble (Eocene Modelling Intercomparison Project; Lunt et al., 2012), which includes previously published early Eocene simulations performed using five GCMs differing in boundary conditions, model structure, and precipitation-relevant parameterisation schemes. We show that an intensified hydrological cycle, manifested in enhanced global precipitation and evaporation rates, is simulated for all Eocene simulations relative to the preindustrial conditions. This is primarily due to elevated atmospheric paleo-CO2, resulting in elevated temperatures, although the effects of differences in paleogeography and ice sheets are also important in some models. For a given CO2 level, globally averaged precipitation rates vary widely between models, largely arising from different simulated surface air temperatures. Models with a similar global sensitivity of precipitation rate to temperature (dP=dT ) display different regional precipitation responses for a given temperature change. Regions that are particularly sensitive to model choice include the South Pacific, tropical Africa, and the Peri-Tethys, which may represent targets for future proxy acquisition. A comparison of early and middle Eocene leaf-fossil-derived precipitation estimates with the GCM output illustrates that GCMs generally underestimate precipitation rates at high latitudes, although a possible seasonal bias of the proxies cannot be excluded. Models which warm these regions, either via elevated CO2 or by varying poorly constrained model parameter values, are most successful in simulating a

The Bond Fluctuation Model and Other Lattice Models

Science.gov (United States)

Müller, Marcus

Lattice models constitute a class of coarse-grained representations of polymeric materials. They have enjoyed a longstanding tradition for investigating the universal behavior of long chain molecules by computer simulations and enumeration techniques. A coarse-grained representation is often necessary to investigate properties on large time- and length scales. First, some justification for using lattice models will be given and the benefits and limitations will be discussed. Then, the bond fluctuation model by Carmesin and Kremer [1] is placed into the context of other lattice models and compared to continuum models. Some specific techniques for measuring the pressure in lattice models will be described. The bond fluctuation model has been employed in more than 100 simulation studies in the last decade and only few selected applications can be mentioned.

A Distributed Snow Evolution Modeling System (SnowModel)

Science.gov (United States)

Liston, G. E.; Elder, K.

2004-12-01

A spatially distributed snow-evolution modeling system (SnowModel) has been specifically designed to be applicable over a wide range of snow landscapes, climates, and conditions. To reach this goal, SnowModel is composed of four sub-models: MicroMet defines the meteorological forcing conditions, EnBal calculates surface energy exchanges, SnowMass simulates snow depth and water-equivalent evolution, and SnowTran-3D accounts for snow redistribution by wind. While other distributed snow models exist, SnowModel is unique in that it includes a well-tested blowing-snow sub-model (SnowTran-3D) for application in windy arctic, alpine, and prairie environments where snowdrifts are common. These environments comprise 68% of the seasonally snow-covered Northern Hemisphere land surface. SnowModel also accounts for snow processes occurring in forested environments (e.g., canopy interception related processes). SnowModel is designed to simulate snow-related physical processes occurring at spatial scales of 5-m and greater, and temporal scales of 1-hour and greater. These include: accumulation from precipitation; wind redistribution and sublimation; loading, unloading, and sublimation within forest canopies; snow-density evolution; and snowpack ripening and melt. To enhance its wide applicability, SnowModel includes the physical calculations required to simulate snow evolution within each of the global snow classes defined by Sturm et al. (1995), e.g., tundra, taiga, alpine, prairie, maritime, and ephemeral snow covers. The three, 25-km by 25-km, Cold Land Processes Experiment (CLPX) mesoscale study areas (MSAs: Fraser, North Park, and Rabbit Ears) are used as SnowModel simulation examples to highlight model strengths, weaknesses, and features in forested, semi-forested, alpine, and shrubland environments.

Event-based model diagnosis of rainfall-runoff model structures

International Nuclear Information System (INIS)

Stanzel, P.

2012-01-01

The objective of this research is a comparative evaluation of different rainfall-runoff model structures. Comparative model diagnostics facilitate the assessment of strengths and weaknesses of each model. The application of multiple models allows an analysis of simulation uncertainties arising from the selection of model structure, as compared with effects of uncertain parameters and precipitation input. Four different model structures, including conceptual and physically based approaches, are compared. In addition to runoff simulations, results for soil moisture and the runoff components of overland flow, interflow and base flow are analysed. Catchment runoff is simulated satisfactorily by all four model structures and shows only minor differences. Systematic deviations from runoff observations provide insight into model structural deficiencies. While physically based model structures capture some single runoff events better, they do not generally outperform conceptual model structures. Contributions to uncertainty in runoff simulations stemming from the choice of model structure show similar dimensions to those arising from parameter selection and the representation of precipitation input. Variations in precipitation mainly affect the general level and peaks of runoff, while different model structures lead to different simulated runoff dynamics. Large differences between the four analysed models are detected for simulations of soil moisture and, even more pronounced, runoff components. Soil moisture changes are more dynamical in the physically based model structures, which is in better agreement with observations. Streamflow contributions of overland flow are considerably lower in these models than in the more conceptual approaches. Observations of runoff components are rarely made and are not available in this study, but are shown to have high potential for an effective selection of appropriate model structures (author) [de

Observation-Based Modeling for Model-Based Testing

NARCIS (Netherlands)

Kanstrén, T.; Piel, E.; Gross, H.G.

2009-01-01

One of the single most important reasons that modeling and modelbased testing are not yet common practice in industry is the perceived difficulty of making the models up to the level of detail and quality required for their automated processing. Models unleash their full potential only through

Multi-Hypothesis Modelling Capabilities for Robust Data-Model Integration

Science.gov (United States)

Walker, A. P.; De Kauwe, M. G.; Lu, D.; Medlyn, B.; Norby, R. J.; Ricciuto, D. M.; Rogers, A.; Serbin, S.; Weston, D. J.; Ye, M.; Zaehle, S.

2017-12-01

Large uncertainty is often inherent in model predictions due to imperfect knowledge of how to describe the mechanistic processes (hypotheses) that a model is intended to represent. Yet this model hypothesis uncertainty (MHU) is often overlooked or informally evaluated, as methods to quantify and evaluate MHU are limited. MHU is increased as models become more complex because each additional processes added to a model comes with inherent MHU as well as parametric unceratinty. With the current trend of adding more processes to Earth System Models (ESMs), we are adding uncertainty, which can be quantified for parameters but not MHU. Model inter-comparison projects do allow for some consideration of hypothesis uncertainty but in an ad hoc and non-independent fashion. This has stymied efforts to evaluate ecosystem models against data and intepret the results mechanistically because it is not simple to interpret exactly why a model is producing the results it does and identify which model assumptions are key as they combine models of many sub-systems and processes, each of which may be conceptualised and represented mathematically in various ways. We present a novel modelling framework—the multi-assumption architecture and testbed (MAAT)—that automates the combination, generation, and execution of a model ensemble built with different representations of process. We will present the argument that multi-hypothesis modelling needs to be considered in conjunction with other capabilities (e.g. the Predictive Ecosystem Analyser; PecAn) and statistical methods (e.g. sensitivity anaylsis, data assimilation) to aid efforts in robust data model integration to enhance our predictive understanding of biological systems.

Process models and model-data fusion in dendroecology

Directory of Open Access Journals (Sweden)

Joel eGuiot

2014-08-01

Full Text Available Dendrochronology (i.e. the study of annually dated tree-ring time series has proved to be a powerful technique to understand tree-growth. This paper intends to show the interest of using ecophysiological modeling not only to understand and predict tree-growth (dendroecology but also to reconstruct past climates (dendroclimatology. Process models have been used for several decades in dendroclimatology, but it is only recently that methods of model-data fusion have led to significant progress in modeling tree-growth as a function of climate and in reconstructing past climates. These model-data fusion (MDF methods, mainly based on the Bayesian paradigm, have been shown to be powerful for both model calibration and model inversion. After a rapid survey of tree-growth modeling, we illustrate MDF with examples based on series of Southern France Aleppo pines and Central France oaks. These examples show that if plants experienced CO2 fertilization, this would have a significant effect on tree-growth which in turn would bias the climate reconstructions. This bias could be extended to other environmental non-climatic factors directly or indirectly affecting annual ring formation and not taken into account in classical empirical models, which supports the use of more complex process-based models. Finally, we conclude by showing the interest of the data assimilation methods applied in climatology to produce climate re-analyses.

`Models of' versus `Models for'. Toward an Agent-Based Conception of Modeling in the Science Classroom

Science.gov (United States)

Gouvea, Julia; Passmore, Cynthia

2017-03-01

The inclusion of the practice of "developing and using models" in the Framework for K-12 Science Education and in the Next Generation Science Standards provides an opportunity for educators to examine the role this practice plays in science and how it can be leveraged in a science classroom. Drawing on conceptions of models in the philosophy of science, we bring forward an agent-based account of models and discuss the implications of this view for enacting modeling in science classrooms. Models, according to this account, can only be understood with respect to the aims and intentions of a cognitive agent (models for), not solely in terms of how they represent phenomena in the world (models of). We present this contrast as a heuristic— models of versus models for—that can be used to help educators notice and interpret how models are positioned in standards, curriculum, and classrooms.

Eclipse models

International Nuclear Information System (INIS)

Michel, F.C.

1989-01-01

Three existing eclipse models for the PSR 1957 + 20 pulsar are discussed in terms of their requirements and the information they yield about the pulsar wind: the interacting wind from a companion model, the magnetosphere model, and the occulting disk model. It is shown out that the wind model requires an MHD wind from the pulsar, with enough particles that the Poynting flux of the wind can be thermalized; in this model, a large flux of energetic radiation from the pulsar is required to accompany the wind and drive the wind off the companion. The magnetosphere model requires an EM wind, which is Poynting flux dominated; the advantage of this model over the wind model is that the plasma density inside the magnetosphere can be orders of magnitude larger than in a magnetospheric tail blown back by wind interaction. The occulting disk model also requires an EM wind so that the interaction would be pushed down onto the companion surface, minimizing direct interaction of the wind with the orbiting macroscopic particles

Thermal unit availability modeling in a regional simulation model

International Nuclear Information System (INIS)

Yamayee, Z.A.; Port, J.; Robinett, W.

1983-01-01

The System Analysis Model (SAM) developed under the umbrella of PNUCC's System Analysis Committee is capable of simulating the operation of a given load/resource scenario. This model employs a Monte-Carlo simulation to incorporate uncertainties. Among uncertainties modeled is thermal unit availability both for energy simulation (seasonal) and capacity simulations (hourly). This paper presents the availability modeling in the capacity and energy models. The use of regional and national data in deriving the two availability models, the interaction between the two and modifications made to the capacity model in order to reflect regional practices is presented. A sample problem is presented to show the modification process. Results for modeling a nuclear unit using NERC-GADS is presented

Using the Model Coupling Toolkit to couple earth system models

Science.gov (United States)

Warner, J.C.; Perlin, N.; Skyllingstad, E.D.

2008-01-01

Continued advances in computational resources are providing the opportunity to operate more sophisticated numerical models. Additionally, there is an increasing demand for multidisciplinary studies that include interactions between different physical processes. Therefore there is a strong desire to develop coupled modeling systems that utilize existing models and allow efficient data exchange and model control. The basic system would entail model "1" running on "M" processors and model "2" running on "N" processors, with efficient exchange of model fields at predetermined synchronization intervals. Here we demonstrate two coupled systems: the coupling of the ocean circulation model Regional Ocean Modeling System (ROMS) to the surface wave model Simulating WAves Nearshore (SWAN), and the coupling of ROMS to the atmospheric model Coupled Ocean Atmosphere Prediction System (COAMPS). Both coupled systems use the Model Coupling Toolkit (MCT) as a mechanism for operation control and inter-model distributed memory transfer of model variables. In this paper we describe requirements and other options for model coupling, explain the MCT library, ROMS, SWAN and COAMPS models, methods for grid decomposition and sparse matrix interpolation, and provide an example from each coupled system. Methods presented in this paper are clearly applicable for coupling of other types of models. ?? 2008 Elsevier Ltd. All rights reserved.

Modeling Non-Gaussian Time Series with Nonparametric Bayesian Model.

Science.gov (United States)

Xu, Zhiguang; MacEachern, Steven; Xu, Xinyi

2015-02-01

We present a class of Bayesian copula models whose major components are the marginal (limiting) distribution of a stationary time series and the internal dynamics of the series. We argue that these are the two features with which an analyst is typically most familiar, and hence that these are natural components with which to work. For the marginal distribution, we use a nonparametric Bayesian prior distribution along with a cdf-inverse cdf transformation to obtain large support. For the internal dynamics, we rely on the traditionally successful techniques of normal-theory time series. Coupling the two components gives us a family of (Gaussian) copula transformed autoregressive models. The models provide coherent adjustments of time scales and are compatible with many extensions, including changes in volatility of the series. We describe basic properties of the models, show their ability to recover non-Gaussian marginal distributions, and use a GARCH modification of the basic model to analyze stock index return series. The models are found to provide better fit and improved short-range and long-range predictions than Gaussian competitors. The models are extensible to a large variety of fields, including continuous time models, spatial models, models for multiple series, models driven by external covariate streams, and non-stationary models.

The Real and the Mathematical in Quantum Modeling: From Principles to Models and from Models to Principles

Science.gov (United States)

Plotnitsky, Arkady

2017-06-01

The history of mathematical modeling outside physics has been dominated by the use of classical mathematical models, C-models, primarily those of a probabilistic or statistical nature. More recently, however, quantum mathematical models, Q-models, based in the mathematical formalism of quantum theory have become more prominent in psychology, economics, and decision science. The use of Q-models in these fields remains controversial, in part because it is not entirely clear whether Q-models are necessary for dealing with the phenomena in question or whether C-models would still suffice. My aim, however, is not to assess the necessity of Q-models in these fields, but instead to reflect on what the possible applicability of Q-models may tell us about the corresponding phenomena there, vis-à-vis quantum phenomena in physics. In order to do so, I shall first discuss the key reasons for the use of Q-models in physics. In particular, I shall examine the fundamental principles that led to the development of quantum mechanics. Then I shall consider a possible role of similar principles in using Q-models outside physics. Psychology, economics, and decision science borrow already available Q-models from quantum theory, rather than derive them from their own internal principles, while quantum mechanics was derived from such principles, because there was no readily available mathematical model to handle quantum phenomena, although the mathematics ultimately used in quantum did in fact exist then. I shall argue, however, that the principle perspective on mathematical modeling outside physics might help us to understand better the role of Q-models in these fields and possibly to envision new models, conceptually analogous to but mathematically different from those of quantum theory, helpful or even necessary there or in physics itself. I shall suggest one possible type of such models, singularized probabilistic, SP, models, some of which are time-dependent, TDSP-models. The

Optimisation of BPMN Business Models via Model Checking

DEFF Research Database (Denmark)

Herbert, Luke Thomas; Sharp, Robin

2013-01-01

We present a framework for the optimisation of business processes modelled in the business process modelling language BPMN, which builds upon earlier work, where we developed a model checking based method for the analysis of BPMN models. We define a structure for expressing optimisation goals...... for synthesized BPMN components, based on probabilistic computation tree logic and real-valued reward structures of the BPMN model, allowing for the specification of complex quantitative goals. We here present a simple algorithm, inspired by concepts from evolutionary algorithms, which iteratively generates...

PENGGUNAAN THE ZMIJEWSKI MODEL, THE ALTMAN MODEL, DAN THE SPRINGATE MODEL SEBAGAI PREDIKTOR DELISTING

Directory of Open Access Journals (Sweden)

Mila Fatmawati

2017-03-01

Full Text Available The purpose of this study was to investigate empirical evidence that the Zmijewski model, the Altman model, andthe Springate models could be used as a predictor of delisting the company. Object of this study was to remove thelist of companies that trade shares (delisted in Indonesia Stock Exchange in 2003-2009. As a benchmark forcompanies delisted at the top used companies that were still listed on the Stock Exchange with the same numberand kind of business field. Comparison samples were taken randomly over the same period with the companydelisted. The method of analysis used logic regression. The results found that from the three delisting of predictormodels, only the Zmijewski models that could be used to predict the company delisted in the period of observation,while the Altman model and the Springate models could not be used as predictive models delisting. It is becauseThe Zmijewski model emphasized amounts of debt in predict delisting. The bigger the debt was, it would be moreaccurate in predicting as the company’s delisting. Meanwhile, the Altman model and the Springate modelemphasized more on profitability measures. The smaller the profitability was, the more precisely to predictcompany’s delisting. Condition of delisting the company that became object of observation company trends wasstill able to get profit, but it had a relative amount of debt.

Process modelling on a canonical basis[Process modelling; Canonical modelling

Energy Technology Data Exchange (ETDEWEB)

Siepmann, Volker

2006-12-20

Based on an equation oriented solving strategy, this thesis investigates a new approach to process modelling. Homogeneous thermodynamic state functions represent consistent mathematical models of thermodynamic properties. Such state functions of solely extensive canonical state variables are the basis of this work, as they are natural objective functions in optimisation nodes to calculate thermodynamic equilibrium regarding phase-interaction and chemical reactions. Analytical state function derivatives are utilised within the solution process as well as interpreted as physical properties. By this approach, only a limited range of imaginable process constraints are considered, namely linear balance equations of state variables. A second-order update of source contributions to these balance equations is obtained by an additional constitutive equation system. These equations are general dependent on state variables and first-order sensitivities, and cover therefore practically all potential process constraints. Symbolic computation technology efficiently provides sparsity and derivative information of active equations to avoid performance problems regarding robustness and computational effort. A benefit of detaching the constitutive equation system is that the structure of the main equation system remains unaffected by these constraints, and a priori information allows to implement an efficient solving strategy and a concise error diagnosis. A tailor-made linear algebra library handles the sparse recursive block structures efficiently. The optimisation principle for single modules of thermodynamic equilibrium is extended to host entire process models. State variables of different modules interact through balance equations, representing material flows from one module to the other. To account for reusability and encapsulation of process module details, modular process modelling is supported by a recursive module structure. The second-order solving algorithm makes it

Generalized latent variable modeling multilevel, longitudinal, and structural equation models

CERN Document Server

Skrondal, Anders; Rabe-Hesketh, Sophia

2004-01-01

This book unifies and extends latent variable models, including multilevel or generalized linear mixed models, longitudinal or panel models, item response or factor models, latent class or finite mixture models, and structural equation models.

A Lagrangian mixing frequency model for transported PDF modeling

Science.gov (United States)

Turkeri, Hasret; Zhao, Xinyu

2017-11-01

In this study, a Lagrangian mixing frequency model is proposed for molecular mixing models within the framework of transported probability density function (PDF) methods. The model is based on the dissipations of mixture fraction and progress variables obtained from Lagrangian particles in PDF methods. The new model is proposed as a remedy to the difficulty in choosing the optimal model constant parameters when using conventional mixing frequency models. The model is implemented in combination with the Interaction by exchange with the mean (IEM) mixing model. The performance of the new model is examined by performing simulations of Sandia Flame D and the turbulent premixed flame from the Cambridge stratified flame series. The simulations are performed using the pdfFOAM solver which is a LES/PDF solver developed entirely in OpenFOAM. A 16-species reduced mechanism is used to represent methane/air combustion, and in situ adaptive tabulation is employed to accelerate the finite-rate chemistry calculations. The results are compared with experimental measurements as well as with the results obtained using conventional mixing frequency models. Dynamic mixing frequencies are predicted using the new model without solving additional transport equations, and good agreement with experimental data is observed.

Modelling MIZ dynamics in a global model

Science.gov (United States)

Rynders, Stefanie; Aksenov, Yevgeny; Feltham, Daniel; Nurser, George; Naveira Garabato, Alberto

2016-04-01

Exposure of large, previously ice-covered areas of the Arctic Ocean to the wind and surface ocean waves results in the Arctic pack ice cover becoming more fragmented and mobile, with large regions of ice cover evolving into the Marginal Ice Zone (MIZ). The need for better climate predictions, along with growing economic activity in the Polar Oceans, necessitates climate and forecasting models that can simulate fragmented sea ice with a greater fidelity. Current models are not fully fit for the purpose, since they neither model surface ocean waves in the MIZ, nor account for the effect of floe fragmentation on drag, nor include sea ice rheology that represents both the now thinner pack ice and MIZ ice dynamics. All these processes affect the momentum transfer to the ocean. We present initial results from a global ocean model NEMO (Nucleus for European Modelling of the Ocean) coupled to the Los Alamos sea ice model CICE. The model setup implements a novel rheological formulation for sea ice dynamics, accounting for ice floe collisions, thus offering a seamless framework for pack ice and MIZ simulations. The effect of surface waves on ice motion is included through wave pressure and the turbulent kinetic energy of ice floes. In the multidecadal model integrations we examine MIZ and basin scale sea ice and oceanic responses to the changes in ice dynamics. We analyse model sensitivities and attribute them to key sea ice and ocean dynamical mechanisms. The results suggest that the effect of the new ice rheology is confined to the MIZ. However with the current increase in summer MIZ area, which is projected to continue and may become the dominant type of sea ice in the Arctic, we argue that the effects of the combined sea ice rheology will be noticeable in large areas of the Arctic Ocean, affecting sea ice and ocean. With this study we assert that to make more accurate sea ice predictions in the changing Arctic, models need to include MIZ dynamics and physics.

Graphical Rasch models

DEFF Research Database (Denmark)

Kreiner, Svend; Christensen, Karl Bang

Rasch models; Partial Credit models; Rating Scale models; Item bias; Differential item functioning; Local independence; Graphical models......Rasch models; Partial Credit models; Rating Scale models; Item bias; Differential item functioning; Local independence; Graphical models...

Transforming Graphical System Models to Graphical Attack Models

DEFF Research Database (Denmark)

Ivanova, Marieta Georgieva; Probst, Christian W.; Hansen, Rene Rydhof

2016-01-01

Manually identifying possible attacks on an organisation is a complex undertaking; many different factors must be considered, and the resulting attack scenarios can be complex and hard to maintain as the organisation changes. System models provide a systematic representation of organisations...... approach to transforming graphical system models to graphical attack models in the form of attack trees. Based on an asset in the model, our transformations result in an attack tree that represents attacks by all possible actors in the model, after which the actor in question has obtained the asset....

Integration of Simulink Models with Component-based Software Models

DEFF Research Database (Denmark)

Marian, Nicolae

2008-01-01

Model based development aims to facilitate the development of embedded control systems by emphasizing the separation of the design level from the implementation level. Model based design involves the use of multiple models that represent different views of a system, having different semantics...... of abstract system descriptions. Usually, in mechatronics systems, design proceeds by iterating model construction, model analysis, and model transformation. Constructing a MATLAB/Simulink model, a plant and controller behavior is simulated using graphical blocks to represent mathematical and logical...... constraints. COMDES (Component-based Design of Software for Distributed Embedded Systems) is such a component-based system framework developed by the software engineering group of Mads Clausen Institute for Product Innovation (MCI), University of Southern Denmark. Once specified, the software model has...

Pavement Aging Model by Response Surface Modeling

Directory of Open Access Journals (Sweden)

Manzano-Ramírez A.

2011-10-01

Full Text Available In this work, surface course aging was modeled by Response Surface Methodology (RSM. The Marshall specimens were placed in a conventional oven for time and temperature conditions established on the basis of the environment factors of the region where the surface course is constructed by AC-20 from the Ing. Antonio M. Amor refinery. Volatilized material (VM, load resistance increment (ΔL and flow resistance increment (ΔF models were developed by the RSM. Cylindrical specimens with real aging were extracted from the surface course pilot to evaluate the error of the models. The VM model was adequate, in contrast (ΔL and (ΔF models were almost adequate with an error of 20 %, that was associated with the other environmental factors, which were not considered at the beginning of the research.

Variable selection and model choice in geoadditive regression models.

Science.gov (United States)

Kneib, Thomas; Hothorn, Torsten; Tutz, Gerhard

2009-06-01

Model choice and variable selection are issues of major concern in practical regression analyses, arising in many biometric applications such as habitat suitability analyses, where the aim is to identify the influence of potentially many environmental conditions on certain species. We describe regression models for breeding bird communities that facilitate both model choice and variable selection, by a boosting algorithm that works within a class of geoadditive regression models comprising spatial effects, nonparametric effects of continuous covariates, interaction surfaces, and varying coefficients. The major modeling components are penalized splines and their bivariate tensor product extensions. All smooth model terms are represented as the sum of a parametric component and a smooth component with one degree of freedom to obtain a fair comparison between the model terms. A generic representation of the geoadditive model allows us to devise a general boosting algorithm that automatically performs model choice and variable selection.

Model coupler for coupling of atmospheric, oceanic, and terrestrial models

International Nuclear Information System (INIS)

Nagai, Haruyasu; Kobayashi, Takuya; Tsuduki, Katsunori; Kim, Keyong-Ok

2007-02-01

A numerical simulation system SPEEDI-MP, which is applicable for various environmental studies, consists of dynamical models and material transport models for the atmospheric, terrestrial, and oceanic environments, meteorological and geographical databases for model inputs, and system utilities for file management, visualization, analysis, etc., using graphical user interfaces (GUIs). As a numerical simulation tool, a model coupling program (model coupler) has been developed. It controls parallel calculations of several models and data exchanges among them to realize the dynamical coupling of the models. It is applicable for any models with three-dimensional structured grid system, which is used by most environmental and hydrodynamic models. A coupled model system for water circulation has been constructed with atmosphere, ocean, wave, hydrology, and land-surface models using the model coupler. Performance tests of the coupled model system for water circulation were also carried out for the flood event at Saudi Arabia in January 2005 and the storm surge case by the hurricane KATRINA in August 2005. (author)

ICRF modelling

International Nuclear Information System (INIS)

Phillips, C.K.

1985-12-01

This lecture provides a survey of the methods used to model fast magnetosonic wave coupling, propagation, and absorption in tokamaks. The validity and limitations of three distinct types of modelling codes, which will be contrasted, include discrete models which utilize ray tracing techniques, approximate continuous field models based on a parabolic approximation of the wave equation, and full field models derived using finite difference techniques. Inclusion of mode conversion effects in these models and modification of the minority distribution function will also be discussed. The lecture will conclude with a presentation of time-dependent global transport simulations of ICRF-heated tokamak discharges obtained in conjunction with the ICRF modelling codes. 52 refs., 15 figs

Event Modeling

DEFF Research Database (Denmark)

Bækgaard, Lars

2001-01-01

The purpose of this chapter is to discuss conceptual event modeling within a context of information modeling. Traditionally, information modeling has been concerned with the modeling of a universe of discourse in terms of information structures. However, most interesting universes of discourse...... are dynamic and we present a modeling approach that can be used to model such dynamics.We characterize events as both information objects and change agents (Bækgaard 1997). When viewed as information objects events are phenomena that can be observed and described. For example, borrow events in a library can...

Degeneracy of time series models: The best model is not always the correct model

International Nuclear Information System (INIS)

Judd, Kevin; Nakamura, Tomomichi

2006-01-01

There are a number of good techniques for finding, in some sense, the best model of a deterministic system given a time series of observations. We examine a problem called model degeneracy, which has the consequence that even when a perfect model of a system exists, one does not find it using the best techniques currently available. The problem is illustrated using global polynomial models and the theory of Groebner bases

On the shell model connection of the cluster model

International Nuclear Information System (INIS)

Cseh, J.; Levai, G.; Kato, K.

2000-01-01

Complete text of publication follows. The interrelation of basic nuclear structure models is a longstanding problem. The connection between the spherical shell model and the quadrupole collective model has been studied extensively, and symmetry considerations proved to be especially useful in this respect. A collective band was interpreted in the shell model language long ago as a set of states (of the valence nucleons) with a specific SU(3) symmetry. Furthermore, the energies of these rotational states are obtained to a good approximation as eigenvalues of an SU(3) dynamically symmetric shell model Hamiltonian. On the other hand the relation of the shell model and cluster model is less well explored. The connection of the harmonic oscillator (i.e. SU(3)) bases of the two approaches is known, but it was established only for the unrealistic harmonic oscillator interactions. Here we investigate the question: Can an SU(3) dynamically symmetric interaction provide a similar connection between the spherical shell model and the cluster model, like the one between the shell and collective models? In other words: whether or not the energy of the states of the cluster bands, defined by a specific SU(3) symmetries, can be obtained from a shell model Hamiltonian (with SU(3) dynamical symmetry). We carried out calculations within the framework of the semimicroscopic algebraic cluster model, in which not only the cluster model space is obtained from the full shell model space by an SU(3) symmetry-dictated truncation, but SU(3) dynamically symmetric interactions are also applied. Actually, Hamiltonians of this kind proved to be successful in describing the gross features of cluster states in a wide energy range. The novel feature of the present work is that we apply exclusively shell model interactions. The energies obtained from such a Hamiltonian for several bands of the ( 12 C, 14 C, 16 O, 20 Ne, 40 Ca) + α systems turn out to be in good agreement with the experimental

Approximating chiral quark models with linear σ-models

International Nuclear Information System (INIS)

Broniowski, Wojciech; Golli, Bojan

2003-01-01

We study the approximation of chiral quark models with simpler models, obtained via gradient expansion. The resulting Lagrangian of the type of the linear σ-model contains, at the lowest level of the gradient-expanded meson action, an additional term of the form ((1)/(2))A(σ∂ μ σ+π∂ μ π) 2 . We investigate the dynamical consequences of this term and its relevance to the phenomenology of the soliton models of the nucleon. It is found that the inclusion of the new term allows for a more efficient approximation of the underlying quark theory, especially in those cases where dynamics allows for a large deviation of the chiral fields from the chiral circle, such as in quark models with non-local regulators. This is of practical importance, since the σ-models with valence quarks only are technically much easier to treat and simpler to solve than the quark models with the full-fledged Dirac sea

Multivariate statistical modelling based on generalized linear models

CERN Document Server

Fahrmeir, Ludwig

1994-01-01

This book is concerned with the use of generalized linear models for univariate and multivariate regression analysis. Its emphasis is to provide a detailed introductory survey of the subject based on the analysis of real data drawn from a variety of subjects including the biological sciences, economics, and the social sciences. Where possible, technical details and proofs are deferred to an appendix in order to provide an accessible account for non-experts. Topics covered include: models for multi-categorical responses, model checking, time series and longitudinal data, random effects models, and state-space models. Throughout, the authors have taken great pains to discuss the underlying theoretical ideas in ways that relate well to the data at hand. As a result, numerous researchers whose work relies on the use of these models will find this an invaluable account to have on their desks. "The basic aim of the authors is to bring together and review a large part of recent advances in statistical modelling of m...

Modeling arson - An exercise in qualitative model building

Science.gov (United States)

Heineke, J. M.

1975-01-01

A detailed example is given of the role of von Neumann and Morgenstern's 1944 'expected utility theorem' (in the theory of games and economic behavior) in qualitative model building. Specifically, an arsonist's decision as to the amount of time to allocate to arson and related activities is modeled, and the responsiveness of this time allocation to changes in various policy parameters is examined. Both the activity modeled and the method of presentation are intended to provide an introduction to the scope and power of the expected utility theorem in modeling situations of 'choice under uncertainty'. The robustness of such a model is shown to vary inversely with the number of preference restrictions used in the analysis. The fewer the restrictions, the wider is the class of agents to which the model is applicable, and accordingly more confidence is put in the derived results. A methodological discussion on modeling human behavior is included.

Air Quality Dispersion Modeling - Alternative Models

Science.gov (United States)

Models, not listed in Appendix W, that can be used in regulatory applications with case-by-case justification to the Reviewing Authority as noted in Section 3.2, Use of Alternative Models, in Appendix W.

On the shell-model-connection of the cluster model

International Nuclear Information System (INIS)

Cseh, J.

2000-01-01

Complete text of publication follows. The interrelation of basic nuclear structure models is a longstanding problem. The connection between the spherical shell model and the quadrupole collective model has been studied extensively, and symmetry considerations proved to be especially useful in this respect. A collective band was interpreted in the shell model language long ago [1] as a set of states (of the valence nucleons) with a specific SU(3) symmetry. Furthermore, the energies of these rotational states are obtained to a good approximation as eigenvalues of an SU(3) dynamically symmetric shell model Hamiltonian. On the other hand the relation of the shell model and cluster model is less well explored. The connection of the harmonic oscillator (i.e. SU(3)) bases of the two approaches is known [2] but it was established only for the unrealistic harmonic oscillator interactions. Here we investigate the question: Can an SU(3) dynamically symmetric interaction provide a similar connection between the spherical shell model and the cluster model, like the one between the shell and collective models? In other words: whether or not the energy of the states of the cluster bands, defined by a specific SU(3) symmetries, can be obtained from a shell model Hamiltonian (with SU(3) dynamical symmetry). We carried out calculations within the framework of the semimicroscopic algebraic cluster model [3,4] in order to find an answer to this question, which seems to be affirmative. In particular, the energies obtained from such a Hamiltonian for several bands of the ( 12 C, 14 C, 16 O, 20 Ne, 40 Ca) + α systems turn out to be in good agreement with the experimental values. The present results show that the simple and transparent SU(3) connection between the spherical shell model and the cluster model is valid not only for the harmonic oscillator interactions, but for much more general (SU(3) dynamically symmetric) Hamiltonians as well, which result in realistic energy spectra. Via

Wind tunnel modeling of roadways: Comparison with mathematical models

International Nuclear Information System (INIS)

Heidorn, K.; Davies, A.E.; Murphy, M.C.

1991-01-01

The assessment of air quality impacts from roadways is a major concern to urban planners. In order to assess future road and building configurations, a number of techniques have been developed including mathematical models, which simulate traffic emissions and atmospheric dispersion through a series of mathematical relationships and physical models. The latter models simulate emissions and dispersion through scaling of these processes in a wind tunnel. Two roadway mathematical models, HIWAY-2 and CALINE-4, were applied to a proposed development in a large urban area. Physical modeling procedures developed by Rowan Williams Davies and Irwin Inc. (RWDI) in the form of line source simulators were also applied, and the resulting carbon monoxide concentrations were compared. The results indicated a factor of two agreement between the mathematical and physical models. The physical model, however, reacted to change in building massing and configuration. The mathematical models did not, since no provision for such changes was included in the mathematical models. In general, the RWDI model resulted in higher concentrations than either HIWAY-2 or CALINE-4. Where there was underprediction, it was often due to shielding of the receptor by surrounding buildings. Comparison of these three models with the CALTRANS Tracer Dispersion Experiment showed good results although concentrations were consistently underpredicted

Analysis of deregulation models; Denryoku shijo jiyuka model no bunseki

Energy Technology Data Exchange (ETDEWEB)

Yajima, M. [Central Research Institute of Electric Power Industry, Tokyo (Japan)

1996-04-01

Trends toward power market deregulation were investigated in Japan and 16 other countries, and various deregulation models were examined and evaluated for their merits and demerits. There are four basic models, that is, franchise bidding model, competitive bidding in power generation model, wholesale wheeling or retail wheeling model, and mandatory pool or voluntary pool model. Power market deregulation has been a global tendency since the second half of the 1970s, with various models adopted by different countries. Out of the above-said models, it is the retail wheeling model and pool models (open access models) that allow the final customer to select power suppliers, and the number of countries adopting these models is increasing. The said models are characterized in that the disintegration of the vertical transmission-distribution integration (separation of distribution service and retail supply service) and the liberation of the retail market are simultaneously accomplished. The pool models, in particular, are enjoying favor because conditions for fair competition have already been prepared and because it is believed high in efficiency. In Japan and France, where importance is attached to atomic power generation, the competitive bidding model is adopted as a means to harmonize the introduction of competition into the source development and power generation sectors. 7 refs., 4 tabs.

Modelling Overview

DEFF Research Database (Denmark)

Larsen, Lars Bjørn; Vesterager, Johan

This report provides an overview of the existing models of global manufacturing, describes the required modelling views and associated methods and identifies tools, which can provide support for this modelling activity.The model adopted for global manufacturing is that of an extended enterprise s...

Statistical Model Checking of Rich Models and Properties

DEFF Research Database (Denmark)

Poulsen, Danny Bøgsted

in undecidability issues for the traditional model checking approaches. Statistical model checking has proven itself a valuable supplement to model checking and this thesis is concerned with extending this software validation technique to stochastic hybrid systems. The thesis consists of two parts: the first part...... motivates why existing model checking technology should be supplemented by new techniques. It also contains a brief introduction to probability theory and concepts covered by the six papers making up the second part. The first two papers are concerned with developing online monitoring techniques...... systems. The fifth paper shows how stochastic hybrid automata are useful for modelling biological systems and the final paper is concerned with showing how statistical model checking is efficiently distributed. In parallel with developing the theory contained in the papers, a substantial part of this work...

Geochemistry Model Validation Report: Material Degradation and Release Model

Energy Technology Data Exchange (ETDEWEB)

H. Stockman

2001-09-28

The purpose of this Analysis and Modeling Report (AMR) is to validate the Material Degradation and Release (MDR) model that predicts degradation and release of radionuclides from a degrading waste package (WP) in the potential monitored geologic repository at Yucca Mountain. This AMR is prepared according to ''Technical Work Plan for: Waste Package Design Description for LA'' (Ref. 17). The intended use of the MDR model is to estimate the long-term geochemical behavior of waste packages (WPs) containing U. S . Department of Energy (DOE) Spent Nuclear Fuel (SNF) codisposed with High Level Waste (HLW) glass, commercial SNF, and Immobilized Plutonium Ceramic (Pu-ceramic) codisposed with HLW glass. The model is intended to predict (1) the extent to which criticality control material, such as gadolinium (Gd), will remain in the WP after corrosion of the initial WP, (2) the extent to which fissile Pu and uranium (U) will be carried out of the degraded WP by infiltrating water, and (3) the chemical composition and amounts of minerals and other solids left in the WP. The results of the model are intended for use in criticality calculations. The scope of the model validation report is to (1) describe the MDR model, and (2) compare the modeling results with experimental studies. A test case based on a degrading Pu-ceramic WP is provided to help explain the model. This model does not directly feed the assessment of system performance. The output from this model is used by several other models, such as the configuration generator, criticality, and criticality consequence models, prior to the evaluation of system performance. This document has been prepared according to AP-3.10Q, ''Analyses and Models'' (Ref. 2), and prepared in accordance with the technical work plan (Ref. 17).

Geochemistry Model Validation Report: Material Degradation and Release Model

International Nuclear Information System (INIS)

Stockman, H.

2001-01-01

The purpose of this Analysis and Modeling Report (AMR) is to validate the Material Degradation and Release (MDR) model that predicts degradation and release of radionuclides from a degrading waste package (WP) in the potential monitored geologic repository at Yucca Mountain. This AMR is prepared according to ''Technical Work Plan for: Waste Package Design Description for LA'' (Ref. 17). The intended use of the MDR model is to estimate the long-term geochemical behavior of waste packages (WPs) containing U. S . Department of Energy (DOE) Spent Nuclear Fuel (SNF) codisposed with High Level Waste (HLW) glass, commercial SNF, and Immobilized Plutonium Ceramic (Pu-ceramic) codisposed with HLW glass. The model is intended to predict (1) the extent to which criticality control material, such as gadolinium (Gd), will remain in the WP after corrosion of the initial WP, (2) the extent to which fissile Pu and uranium (U) will be carried out of the degraded WP by infiltrating water, and (3) the chemical composition and amounts of minerals and other solids left in the WP. The results of the model are intended for use in criticality calculations. The scope of the model validation report is to (1) describe the MDR model, and (2) compare the modeling results with experimental studies. A test case based on a degrading Pu-ceramic WP is provided to help explain the model. This model does not directly feed the assessment of system performance. The output from this model is used by several other models, such as the configuration generator, criticality, and criticality consequence models, prior to the evaluation of system performance. This document has been prepared according to AP-3.10Q, ''Analyses and Models'' (Ref. 2), and prepared in accordance with the technical work plan (Ref. 17)

Assessing physical models used in nuclear aerosol transport models

International Nuclear Information System (INIS)

McDonald, B.H.

1987-01-01

Computer codes used to predict the behaviour of aerosols in water-cooled reactor containment buildings after severe accidents contain a variety of physical models. Special models are in place for describing agglomeration processes where small aerosol particles combine to form larger ones. Other models are used to calculate the rates at which aerosol particles are deposited on building structures. Condensation of steam on aerosol particles is currently a very active area in aerosol modelling. In this paper, the physical models incorporated in the current available international codes for all of these processes are reviewed and documented. There is considerable variation in models used in different codes, and some uncertainties exist as to which models are superior. 28 refs

Particle Tracking Model (PTM) with Coastal Modeling System (CMS)

Science.gov (United States)

2015-11-04

Coastal Inlets Research Program Particle Tracking Model (PTM) with Coastal Modeling System ( CMS ) The Particle Tracking Model (PTM) is a Lagrangian...currents and waves. The Coastal Inlets Research Program (CIRP) supports the PTM with the Coastal Modeling System ( CMS ), which provides coupled wave...and current forcing for PTM simulations. CMS -PTM is implemented in the Surface-water Modeling System, a GUI environment for input development

A BRDF statistical model applying to space target materials modeling

Science.gov (United States)

Liu, Chenghao; Li, Zhi; Xu, Can; Tian, Qichen

2017-10-01

In order to solve the problem of poor effect in modeling the large density BRDF measured data with five-parameter semi-empirical model, a refined statistical model of BRDF which is suitable for multi-class space target material modeling were proposed. The refined model improved the Torrance-Sparrow model while having the modeling advantages of five-parameter model. Compared with the existing empirical model, the model contains six simple parameters, which can approximate the roughness distribution of the material surface, can approximate the intensity of the Fresnel reflectance phenomenon and the attenuation of the reflected light's brightness with the azimuth angle changes. The model is able to achieve parameter inversion quickly with no extra loss of accuracy. The genetic algorithm was used to invert the parameters of 11 different samples in the space target commonly used materials, and the fitting errors of all materials were below 6%, which were much lower than those of five-parameter model. The effect of the refined model is verified by comparing the fitting results of the three samples at different incident zenith angles in 0° azimuth angle. Finally, the three-dimensional modeling visualizations of these samples in the upper hemisphere space was given, in which the strength of the optical scattering of different materials could be clearly shown. It proved the good describing ability of the refined model at the material characterization as well.

EIA model documentation: Petroleum market model of the national energy modeling system

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-12-28

The purpose of this report is to define the objectives of the Petroleum Market Model (PMM), describe its basic approach, and provide detail on how it works. This report is intended as a reference document for model analysts, users, and the public. Documentation of the model is in accordance with EIA`s legal obligation to provide adequate documentation in support of its models. The PMM models petroleum refining activities, the marketing of petroleum products to consumption regions, the production of natural gas liquids in gas processing plants, and domestic methanol production. The PMM projects petroleum product prices and sources of supply for meeting petroleum product demand. The sources of supply include crude oil, both domestic and imported; other inputs including alcohols and ethers; natural gas plant liquids production; petroleum product imports; and refinery processing gain. In addition, the PMM estimates domestic refinery capacity expansion and fuel consumption. Product prices are estimated at the Census division level and much of the refining activity information is at the Petroleum Administration for Defense (PAD) District level.

EIA model documentation: Petroleum market model of the national energy modeling system

International Nuclear Information System (INIS)

1995-01-01

The purpose of this report is to define the objectives of the Petroleum Market Model (PMM), describe its basic approach, and provide detail on how it works. This report is intended as a reference document for model analysts, users, and the public. Documentation of the model is in accordance with EIA's legal obligation to provide adequate documentation in support of its models. The PMM models petroleum refining activities, the marketing of petroleum products to consumption regions, the production of natural gas liquids in gas processing plants, and domestic methanol production. The PMM projects petroleum product prices and sources of supply for meeting petroleum product demand. The sources of supply include crude oil, both domestic and imported; other inputs including alcohols and ethers; natural gas plant liquids production; petroleum product imports; and refinery processing gain. In addition, the PMM estimates domestic refinery capacity expansion and fuel consumption. Product prices are estimated at the Census division level and much of the refining activity information is at the Petroleum Administration for Defense (PAD) District level

Towards policy relevant environmental modeling: contextual validity and pragmatic models

Science.gov (United States)

Miles, Scott B.

2000-01-01

"What makes for a good model?" In various forms, this question is a question that, undoubtedly, many people, businesses, and institutions ponder with regards to their particular domain of modeling. One particular domain that is wrestling with this question is the multidisciplinary field of environmental modeling. Examples of environmental models range from models of contaminated ground water flow to the economic impact of natural disasters, such as earthquakes. One of the distinguishing claims of the field is the relevancy of environmental modeling to policy and environment-related decision-making in general. A pervasive view by both scientists and decision-makers is that a "good" model is one that is an accurate predictor. Thus, determining whether a model is "accurate" or "correct" is done by comparing model output to empirical observations. The expected outcome of this process, usually referred to as "validation" or "ground truthing," is a stamp on the model in question of "valid" or "not valid" that serves to indicate whether or not the model will be reliable before it is put into service in a decision-making context. In this paper, I begin by elaborating on the prevailing view of model validation and why this view must change. Drawing from concepts coming out of the studies of science and technology, I go on to propose a contextual view of validity that can overcome the problems associated with "ground truthing" models as an indicator of model goodness. The problem of how we talk about and determine model validity has much to do about how we perceive the utility of environmental models. In the remainder of the paper, I argue that we should adopt ideas of pragmatism in judging what makes for a good model and, in turn, developing good models. From such a perspective of model goodness, good environmental models should facilitate communication, convey—not bury or "eliminate"—uncertainties, and, thus, afford the active building of consensus decisions, instead

Stochastic biomathematical models with applications to neuronal modeling

CERN Document Server

Batzel, Jerry; Ditlevsen, Susanne

2013-01-01

Stochastic biomathematical models are becoming increasingly important as new light is shed on the role of noise in living systems. In certain biological systems, stochastic effects may even enhance a signal, thus providing a biological motivation for the noise observed in living systems. Recent advances in stochastic analysis and increasing computing power facilitate the analysis of more biophysically realistic models, and this book provides researchers in computational neuroscience and stochastic systems with an overview of recent developments. Key concepts are developed in chapters written by experts in their respective fields. Topics include: one-dimensional homogeneous diffusions and their boundary behavior, large deviation theory and its application in stochastic neurobiological models, a review of mathematical methods for stochastic neuronal integrate-and-fire models, stochastic partial differential equation models in neurobiology, and stochastic modeling of spreading cortical depression.

Modelling of an homogeneous equilibrium mixture model

International Nuclear Information System (INIS)

Bernard-Champmartin, A.; Poujade, O.; Mathiaud, J.; Mathiaud, J.; Ghidaglia, J.M.

2014-01-01

We present here a model for two phase flows which is simpler than the 6-equations models (with two densities, two velocities, two temperatures) but more accurate than the standard mixture models with 4 equations (with two densities, one velocity and one temperature). We are interested in the case when the two-phases have been interacting long enough for the drag force to be small but still not negligible. The so-called Homogeneous Equilibrium Mixture Model (HEM) that we present is dealing with both mixture and relative quantities, allowing in particular to follow both a mixture velocity and a relative velocity. This relative velocity is not tracked by a conservation law but by a closure law (drift relation), whose expression is related to the drag force terms of the two-phase flow. After the derivation of the model, a stability analysis and numerical experiments are presented. (authors)

Temperature-based modeling of reference evapotranspiration using several artificial intelligence models: application of different modeling scenarios

Science.gov (United States)

Sanikhani, Hadi; Kisi, Ozgur; Maroufpoor, Eisa; Yaseen, Zaher Mundher

2018-02-01

The establishment of an accurate computational model for predicting reference evapotranspiration (ET0) process is highly essential for several agricultural and hydrological applications, especially for the rural water resource systems, water use allocations, utilization and demand assessments, and the management of irrigation systems. In this research, six artificial intelligence (AI) models were investigated for modeling ET0 using a small number of climatic data generated from the minimum and maximum temperatures of the air and extraterrestrial radiation. The investigated models were multilayer perceptron (MLP), generalized regression neural networks (GRNN), radial basis neural networks (RBNN), integrated adaptive neuro-fuzzy inference systems with grid partitioning and subtractive clustering (ANFIS-GP and ANFIS-SC), and gene expression programming (GEP). The implemented monthly time scale data set was collected at the Antalya and Isparta stations which are located in the Mediterranean Region of Turkey. The Hargreaves-Samani (HS) equation and its calibrated version (CHS) were used to perform a verification analysis of the established AI models. The accuracy of validation was focused on multiple quantitative metrics, including root mean squared error (RMSE), mean absolute error (MAE), correlation coefficient (R 2), coefficient of residual mass (CRM), and Nash-Sutcliffe efficiency coefficient (NS). The results of the conducted models were highly practical and reliable for the investigated case studies. At the Antalya station, the performance of the GEP and GRNN models was better than the other investigated models, while the performance of the RBNN and ANFIS-SC models was best compared to the other models at the Isparta station. Except for the MLP model, all the other investigated models presented a better performance accuracy compared to the HS and CHS empirical models when applied in a cross-station scenario. A cross-station scenario examination implies the

Deformed baryons: constituent quark model vs. bag model

International Nuclear Information System (INIS)

Iwamura, Y.; Nogami, Y.

1985-01-01

Recently Bhaduri et al. developed a nonrelativistic constituent quark model for deformed baryons. In that model the quarks move in a deformable mean field, and the deformation parameters are determined by minimizing the quark energy subject to the constraint of volume conservation. This constraint is an ad hoc assumption. It is shown that, starting with a bag model, a model similar to that of Bhaduri et al. can be constructed. The deformation parameters are determined by the pressure balance on the bag surface. There is, however, a distinct difference between the two models with respect to the state dependence of the ''volume''. Implications of this difference are discussed

Business Model Innovation: How Iconic Business Models Emerge

OpenAIRE

Mikhalkina, T.; Cabantous, L.

2015-01-01

Despite ample research on the topic of business model innovation, little is known about the cognitive processes whereby some innovative business models gain the status of iconic representations of particular types of firms. This study addresses the question: How do iconic business models emerge? In other words: How do innovative business models become prototypical exemplars for new categories of firms? We focus on the case of Airbnb, and analyze how six mainstream business media publications ...

ECONOMIC MODELING STOCKS CONTROL SYSTEM: SIMULATION MODEL

OpenAIRE

Климак, М.С.; Войтко, С.В.

2016-01-01

Considered theoretical and applied aspects of the development of simulation models to predictthe optimal development and production systems that create tangible products andservices. It isproved that theprocessof inventory control needs of economicandmathematical modeling in viewof thecomplexity of theoretical studies. A simulation model of stocks control that allows make managementdecisions with production logistics

Bayesian Model Averaging of Artificial Intelligence Models for Hydraulic Conductivity Estimation

Science.gov (United States)

Nadiri, A.; Chitsazan, N.; Tsai, F. T.; Asghari Moghaddam, A.

2012-12-01

This research presents a Bayesian artificial intelligence model averaging (BAIMA) method that incorporates multiple artificial intelligence (AI) models to estimate hydraulic conductivity and evaluate estimation uncertainties. Uncertainty in the AI model outputs stems from error in model input as well as non-uniqueness in selecting different AI methods. Using one single AI model tends to bias the estimation and underestimate uncertainty. BAIMA employs Bayesian model averaging (BMA) technique to address the issue of using one single AI model for estimation. BAIMA estimates hydraulic conductivity by averaging the outputs of AI models according to their model weights. In this study, the model weights were determined using the Bayesian information criterion (BIC) that follows the parsimony principle. BAIMA calculates the within-model variances to account for uncertainty propagation from input data to AI model output. Between-model variances are evaluated to account for uncertainty due to model non-uniqueness. We employed Takagi-Sugeno fuzzy logic (TS-FL), artificial neural network (ANN) and neurofuzzy (NF) to estimate hydraulic conductivity for the Tasuj plain aquifer, Iran. BAIMA combined three AI models and produced better fitting than individual models. While NF was expected to be the best AI model owing to its utilization of both TS-FL and ANN models, the NF model is nearly discarded by the parsimony principle. The TS-FL model and the ANN model showed equal importance although their hydraulic conductivity estimates were quite different. This resulted in significant between-model variances that are normally ignored by using one AI model.

Climate simulations for 1880-2003 with GISS modelE

International Nuclear Information System (INIS)

Hansen, J.; Lacis, A.; Miller, R.; Schmidt, G.A.; Russell, G.; Canuto, V.; Del Genio, A.; Hall, T.; Hansen, J.; Sato, M.; Kharecha, P.; Nazarenko, L.; Aleinov, I.; Bauer, S.; Chandler, M.; Faluvegi, G.; Jonas, J.; Ruedy, R.; Lo, K.; Cheng, Y.; Lacis, A.; Schmidt, G.A.; Del Genio, A.; Miller, R.; Cairns, B.; Hall, T.; Baum, E.; Cohen, A.; Fleming, E.; Jackman, C.; Friend, A.; Kelley, M.

2007-01-01

We carry out climate simulations for 1880-2003 with GISS modelE driven by ten measured or estimated climate forcing. An ensemble of climate model runs is carried out for each forcing acting individually and for all forcing mechanisms acting together. We compare side-by-side simulated climate change for each forcing, all forcing, observations, unforced variability among model ensemble members, and, if available, observed variability. Discrepancies between observations and simulations with all forcing are due to model deficiencies, inaccurate or incomplete forcing, and imperfect observations. Although there are notable discrepancies between model and observations, the fidelity is sufficient to encourage use of the model for simulations of future climate change. By using a fixed well-documented model and accurately defining the 1880-2003 forcing, we aim to provide a benchmark against which the effect of improvements in the model, climate forcing, and observations can be tested. Principal model deficiencies include unrealistic weak tropical El Nino-like variability and a poor distribution of sea ice, with too much sea ice in the Northern Hemisphere and too little in the Southern Hemisphere. Greatest uncertainties in the forcing are the temporal and spatial variations of anthropogenic aerosols and their indirect effects on clouds. (authors)

ModelMage: a tool for automatic model generation, selection and management.

Science.gov (United States)

Flöttmann, Max; Schaber, Jörg; Hoops, Stephan; Klipp, Edda; Mendes, Pedro

2008-01-01

Mathematical modeling of biological systems usually involves implementing, simulating, and discriminating several candidate models that represent alternative hypotheses. Generating and managing these candidate models is a tedious and difficult task and can easily lead to errors. ModelMage is a tool that facilitates management of candidate models. It is designed for the easy and rapid development, generation, simulation, and discrimination of candidate models. The main idea of the program is to automatically create a defined set of model alternatives from a single master model. The user provides only one SBML-model and a set of directives from which the candidate models are created by leaving out species, modifiers or reactions. After generating models the software can automatically fit all these models to the data and provides a ranking for model selection, in case data is available. In contrast to other model generation programs, ModelMage aims at generating only a limited set of models that the user can precisely define. ModelMage uses COPASI as a simulation and optimization engine. Thus, all simulation and optimization features of COPASI are readily incorporated. ModelMage can be downloaded from http://sysbio.molgen.mpg.de/modelmage and is distributed as free software.

Modelling binary data

CERN Document Server

Collett, David

2002-01-01

INTRODUCTION Some Examples The Scope of this Book Use of Statistical Software STATISTICAL INFERENCE FOR BINARY DATA The Binomial Distribution Inference about the Success Probability Comparison of Two Proportions Comparison of Two or More Proportions MODELS FOR BINARY AND BINOMIAL DATA Statistical Modelling Linear Models Methods of Estimation Fitting Linear Models to Binomial Data Models for Binomial Response Data The Linear Logistic Model Fitting the Linear Logistic Model to Binomial Data Goodness of Fit of a Linear Logistic Model Comparing Linear Logistic Models Linear Trend in Proportions Comparing Stimulus-Response Relationships Non-Convergence and Overfitting Some other Goodness of Fit Statistics Strategy for Model Selection Predicting a Binary Response Probability BIOASSAY AND SOME OTHER APPLICATIONS The Tolerance Distribution Estimating an Effective Dose Relative Potency Natural Response Non-Linear Logistic Regression Models Applications of the Complementary Log-Log Model MODEL CHECKING Definition of Re...

Model theory

CERN Document Server

Chang, CC

2012-01-01

Model theory deals with a branch of mathematical logic showing connections between a formal language and its interpretations or models. This is the first and most successful textbook in logical model theory. Extensively updated and corrected in 1990 to accommodate developments in model theoretic methods - including classification theory and nonstandard analysis - the third edition added entirely new sections, exercises, and references. Each chapter introduces an individual method and discusses specific applications. Basic methods of constructing models include constants, elementary chains, Sko

Multistate Model Builder (MSMB): a flexible editor for compact biochemical models.

Science.gov (United States)

Palmisano, Alida; Hoops, Stefan; Watson, Layne T; Jones, Thomas C; Tyson, John J; Shaffer, Clifford A

2014-04-04

Building models of molecular regulatory networks is challenging not just because of the intrinsic difficulty of describing complex biological processes. Writing a model is a creative effort that calls for more flexibility and interactive support than offered by many of today's biochemical model editors. Our model editor MSMB - Multistate Model Builder - supports multistate models created using different modeling styles. MSMB provides two separate advances on existing network model editors. (1) A simple but powerful syntax is used to describe multistate species. This reduces the number of reactions needed to represent certain molecular systems, thereby reducing the complexity of model creation. (2) Extensive feedback is given during all stages of the model creation process on the existing state of the model. Users may activate error notifications of varying stringency on the fly, and use these messages as a guide toward a consistent, syntactically correct model. MSMB default values and behavior during model manipulation (e.g., when renaming or deleting an element) can be adapted to suit the modeler, thus supporting creativity rather than interfering with it. MSMB's internal model representation allows saving a model with errors and inconsistencies (e.g., an undefined function argument; a syntactically malformed reaction). A consistent model can be exported to SBML or COPASI formats. We show the effectiveness of MSMB's multistate syntax through models of the cell cycle and mRNA transcription. Using multistate reactions reduces the number of reactions need to encode many biochemical network models. This reduces the cognitive load for a given model, thereby making it easier for modelers to build more complex models. The many interactive editing support features provided by MSMB make it easier for modelers to create syntactically valid models, thus speeding model creation. Complete information and the installation package can be found at http

Application of Improved Radiation Modeling to General Circulation Models

Energy Technology Data Exchange (ETDEWEB)

Michael J Iacono

2011-04-07

This research has accomplished its primary objectives of developing accurate and efficient radiation codes, validating them with measurements and higher resolution models, and providing these advancements to the global modeling community to enhance the treatment of cloud and radiative processes in weather and climate prediction models. A critical component of this research has been the development of the longwave and shortwave broadband radiative transfer code for general circulation model (GCM) applications, RRTMG, which is based on the single-column reference code, RRTM, also developed at AER. RRTMG is a rigorously tested radiation model that retains a considerable level of accuracy relative to higher resolution models and measurements despite the performance enhancements that have made it possible to apply this radiation code successfully to global dynamical models. This model includes the radiative effects of all significant atmospheric gases, and it treats the absorption and scattering from liquid and ice clouds and aerosols. RRTMG also includes a statistical technique for representing small-scale cloud variability, such as cloud fraction and the vertical overlap of clouds, which has been shown to improve cloud radiative forcing in global models. This development approach has provided a direct link from observations to the enhanced radiative transfer provided by RRTMG for application to GCMs. Recent comparison of existing climate model radiation codes with high resolution models has documented the improved radiative forcing capability provided by RRTMG, especially at the surface, relative to other GCM radiation models. Due to its high accuracy, its connection to observations, and its computational efficiency, RRTMG has been implemented operationally in many national and international dynamical models to provide validated radiative transfer for improving weather forecasts and enhancing the prediction of global climate change.

Modeling Guru: Knowledge Base for NASA Modelers

Science.gov (United States)

Seablom, M. S.; Wojcik, G. S.; van Aartsen, B. H.

2009-05-01

Modeling Guru is an on-line knowledge-sharing resource for anyone involved with or interested in NASA's scientific models or High End Computing (HEC) systems. Developed and maintained by the NASA's Software Integration and Visualization Office (SIVO) and the NASA Center for Computational Sciences (NCCS), Modeling Guru's combined forums and knowledge base for research and collaboration is becoming a repository for the accumulated expertise of NASA's scientific modeling and HEC communities. All NASA modelers and associates are encouraged to participate and provide knowledge about the models and systems so that other users may benefit from their experience. Modeling Guru is divided into a hierarchy of communities, each with its own set forums and knowledge base documents. Current modeling communities include those for space science, land and atmospheric dynamics, atmospheric chemistry, and oceanography. In addition, there are communities focused on NCCS systems, HEC tools and libraries, and programming and scripting languages. Anyone may view most of the content on Modeling Guru (available at http://modelingguru.nasa.gov/), but you must log in to post messages and subscribe to community postings. The site offers a full range of "Web 2.0" features, including discussion forums, "wiki" document generation, document uploading, RSS feeds, search tools, blogs, email notification, and "breadcrumb" links. A discussion (a.k.a. forum "thread") is used to post comments, solicit feedback, or ask questions. If marked as a question, SIVO will monitor the thread, and normally respond within a day. Discussions can include embedded images, tables, and formatting through the use of the Rich Text Editor. Also, the user can add "Tags" to their thread to facilitate later searches. The "knowledge base" is comprised of documents that are used to capture and share expertise with others. The default "wiki" document lets users edit within the browser so others can easily collaborate on the

Modeling soil water content for vegetation modeling improvement

Science.gov (United States)

Cianfrani, Carmen; Buri, Aline; Zingg, Barbara; Vittoz, Pascal; Verrecchia, Eric; Guisan, Antoine

2016-04-01

Soil water content (SWC) is known to be important for plants as it affects the physiological processes regulating plant growth. Therefore, SWC controls plant distribution over the Earth surface, ranging from deserts and grassland to rain forests. Unfortunately, only a few data on SWC are available as its measurement is very time consuming and costly and needs specific laboratory tools. The scarcity of SWC measurements in geographic space makes it difficult to model and spatially project SWC over larger areas. In particular, it prevents its inclusion in plant species distribution model (SDMs) as predictor. The aims of this study were, first, to test a new methodology allowing problems of the scarcity of SWC measurements to be overpassed and second, to model and spatially project SWC in order to improve plant SDMs with the inclusion of SWC parameter. The study was developed in four steps. First, SWC was modeled by measuring it at 10 different pressures (expressed in pF and ranging from pF=0 to pF=4.2). The different pF represent different degrees of soil water availability for plants. An ensemble of bivariate models was built to overpass the problem of having only a few SWC measurements (n = 24) but several predictors to include in the model. Soil texture (clay, silt, sand), organic matter (OM), topographic variables (elevation, aspect, convexity), climatic variables (precipitation) and hydrological variables (river distance, NDWI) were used as predictors. Weighted ensemble models were built using only bivariate models with adjusted-R2 > 0.5 for each SWC at different pF. The second step consisted in running plant SDMs including modeled SWC jointly with the conventional topo-climatic variable used for plant SDMs. Third, SDMs were only run using the conventional topo-climatic variables. Finally, comparing the models obtained in the second and third steps allowed assessing the additional predictive power of SWC in plant SDMs. SWC ensemble models remained very good, with

Computer-aided modeling framework – a generic modeling template

DEFF Research Database (Denmark)

Fedorova, Marina; Sin, Gürkan; Gani, Rafiqul

and test models systematically, efficiently and reliably. In this way, development of products and processes can be made faster, cheaper and more efficient. In this contribution, as part of the framework, a generic modeling template for the systematic derivation of problem specific models is presented....... The application of the modeling template is highlighted with a case study related to the modeling of a catalytic membrane reactor coupling dehydrogenation of ethylbenzene with hydrogenation of nitrobenzene...

A simplified model exploration research of new anisotropic diffuse radiation model

International Nuclear Information System (INIS)

Yao, Wanxiang; Li, Zhengrong; Wang, Xiao; Zhao, Qun; Zhang, Zhigang; Lin, Lin

2016-01-01

Graphical abstract: The specific process of measured diffuse radiation data. - Highlights: • Simplified diffuse radiation model is extremely important for solar radiation simulation and energy simulation. • A new simplified anisotropic diffuse radiation model (NSADR model) is proposed. • The accuracy of existing models and NSADR model is compared based on the measured values. • The accuracy of the NSADR model is higher than that of the existing models, and suitable for calculating diffuse radiation. - Abstract: More accurate new anisotropic diffuse radiation model (NADR model) has been proposed, but the parameters and calculation process of NADR model used in the process are complex. So it is difficult to widely used in the simulation software and engineering calculation. Based on analysis of the diffuse radiation model and measured diffuse radiation data, this paper put forward three hypotheses: (1) diffuse radiation from sky horizontal region is concentrated in a very thin layer which is close to the line source; (2) diffuse radiation from circumsolar region is concentrated in the point of the sun; (3) diffuse radiation from orthogonal region is concentrated in the point located at 90 degree angles with the Sun. Based on these hypotheses, NADR model is simplified to a new simplified anisotropic diffuse radiation model (NSADR model). Then the accuracy of NADR model and its simplified model (NSADR model) are compared with existing models based on the measured values, and the result shows that Perez model and its simplified model are relatively accurate among existing models. However, the accuracy of these two models is lower than the NADR model and NSADR model due to neglect the influence of the orthogonal diffuse radiation. The accuracy of the NSADR model is higher than that of the existing models, meanwhile, another advantage is that the NSADR model simplifies the process of solution parameters and calculation. Therefore it is more suitable for

Biosphere Model Report

Energy Technology Data Exchange (ETDEWEB)

D. W. Wu

2003-07-16

The purpose of this report is to document the biosphere model, the Environmental Radiation Model for Yucca Mountain, Nevada (ERMYN), which describes radionuclide transport processes in the biosphere and associated human exposure that may arise as the result of radionuclide release from the geologic repository at Yucca Mountain. The biosphere model is one of the process models that support the Yucca Mountain Project (YMP) Total System Performance Assessment (TSPA) for the license application (LA), the TSPA-LA. The ERMYN model provides the capability of performing human radiation dose assessments. This report documents the biosphere model, which includes: (1) Describing the reference biosphere, human receptor, exposure scenarios, and primary radionuclides for each exposure scenario (Section 6.1); (2) Developing a biosphere conceptual model using site-specific features, events, and processes (FEPs), the reference biosphere, the human receptor, and assumptions (Section 6.2 and Section 6.3); (3) Building a mathematical model using the biosphere conceptual model and published biosphere models (Sections 6.4 and 6.5); (4) Summarizing input parameters for the mathematical model, including the uncertainty associated with input values (Section 6.6); (5) Identifying improvements in the ERMYN model compared with the model used in previous biosphere modeling (Section 6.7); (6) Constructing an ERMYN implementation tool (model) based on the biosphere mathematical model using GoldSim stochastic simulation software (Sections 6.8 and 6.9); (7) Verifying the ERMYN model by comparing output from the software with hand calculations to ensure that the GoldSim implementation is correct (Section 6.10); and (8) Validating the ERMYN model by corroborating it with published biosphere models; comparing conceptual models, mathematical models, and numerical results (Section 7).

Biosphere Model Report

Energy Technology Data Exchange (ETDEWEB)

M. A. Wasiolek

2003-10-27

The purpose of this report is to document the biosphere model, the Environmental Radiation Model for Yucca Mountain, Nevada (ERMYN), which describes radionuclide transport processes in the biosphere and associated human exposure that may arise as the result of radionuclide release from the geologic repository at Yucca Mountain. The biosphere model is one of the process models that support the Yucca Mountain Project (YMP) Total System Performance Assessment (TSPA) for the license application (LA), the TSPA-LA. The ERMYN model provides the capability of performing human radiation dose assessments. This report documents the biosphere model, which includes: (1) Describing the reference biosphere, human receptor, exposure scenarios, and primary radionuclides for each exposure scenario (Section 6.1); (2) Developing a biosphere conceptual model using site-specific features, events, and processes (FEPs), the reference biosphere, the human receptor, and assumptions (Section 6.2 and Section 6.3); (3) Building a mathematical model using the biosphere conceptual model and published biosphere models (Sections 6.4 and 6.5); (4) Summarizing input parameters for the mathematical model, including the uncertainty associated with input values (Section 6.6); (5) Identifying improvements in the ERMYN model compared with the model used in previous biosphere modeling (Section 6.7); (6) Constructing an ERMYN implementation tool (model) based on the biosphere mathematical model using GoldSim stochastic simulation software (Sections 6.8 and 6.9); (7) Verifying the ERMYN model by comparing output from the software with hand calculations to ensure that the GoldSim implementation is correct (Section 6.10); and (8) Validating the ERMYN model by corroborating it with published biosphere models; comparing conceptual models, mathematical models, and numerical results (Section 7).

Biosphere Model Report

International Nuclear Information System (INIS)

D. W. Wu

2003-01-01

The purpose of this report is to document the biosphere model, the Environmental Radiation Model for Yucca Mountain, Nevada (ERMYN), which describes radionuclide transport processes in the biosphere and associated human exposure that may arise as the result of radionuclide release from the geologic repository at Yucca Mountain. The biosphere model is one of the process models that support the Yucca Mountain Project (YMP) Total System Performance Assessment (TSPA) for the license application (LA), the TSPA-LA. The ERMYN model provides the capability of performing human radiation dose assessments. This report documents the biosphere model, which includes: (1) Describing the reference biosphere, human receptor, exposure scenarios, and primary radionuclides for each exposure scenario (Section 6.1); (2) Developing a biosphere conceptual model using site-specific features, events, and processes (FEPs), the reference biosphere, the human receptor, and assumptions (Section 6.2 and Section 6.3); (3) Building a mathematical model using the biosphere conceptual model and published biosphere models (Sections 6.4 and 6.5); (4) Summarizing input parameters for the mathematical model, including the uncertainty associated with input values (Section 6.6); (5) Identifying improvements in the ERMYN model compared with the model used in previous biosphere modeling (Section 6.7); (6) Constructing an ERMYN implementation tool (model) based on the biosphere mathematical model using GoldSim stochastic simulation software (Sections 6.8 and 6.9); (7) Verifying the ERMYN model by comparing output from the software with hand calculations to ensure that the GoldSim implementation is correct (Section 6.10); and (8) Validating the ERMYN model by corroborating it with published biosphere models; comparing conceptual models, mathematical models, and numerical results (Section 7)

A Primer for Model Selection: The Decisive Role of Model Complexity

Science.gov (United States)

Höge, Marvin; Wöhling, Thomas; Nowak, Wolfgang

2018-03-01

Selecting a "best" model among several competing candidate models poses an often encountered problem in water resources modeling (and other disciplines which employ models). For a modeler, the best model fulfills a certain purpose best (e.g., flood prediction), which is typically assessed by comparing model simulations to data (e.g., stream flow). Model selection methods find the "best" trade-off between good fit with data and model complexity. In this context, the interpretations of model complexity implied by different model selection methods are crucial, because they represent different underlying goals of modeling. Over the last decades, numerous model selection criteria have been proposed, but modelers who primarily want to apply a model selection criterion often face a lack of guidance for choosing the right criterion that matches their goal. We propose a classification scheme for model selection criteria that helps to find the right criterion for a specific goal, i.e., which employs the correct complexity interpretation. We identify four model selection classes which seek to achieve high predictive density, low predictive error, high model probability, or shortest compression of data. These goals can be achieved by following either nonconsistent or consistent model selection and by either incorporating a Bayesian parameter prior or not. We allocate commonly used criteria to these four classes, analyze how they represent model complexity and what this means for the model selection task. Finally, we provide guidance on choosing the right type of criteria for specific model selection tasks. (A quick guide through all key points is given at the end of the introduction.)

Model-free and model-based reward prediction errors in EEG.

Science.gov (United States)

Sambrook, Thomas D; Hardwick, Ben; Wills, Andy J; Goslin, Jeremy

2018-05-24

Learning theorists posit two reinforcement learning systems: model-free and model-based. Model-based learning incorporates knowledge about structure and contingencies in the world to assign candidate actions with an expected value. Model-free learning is ignorant of the world's structure; instead, actions hold a value based on prior reinforcement, with this value updated by expectancy violation in the form of a reward prediction error. Because they use such different learning mechanisms, it has been previously assumed that model-based and model-free learning are computationally dissociated in the brain. However, recent fMRI evidence suggests that the brain may compute reward prediction errors to both model-free and model-based estimates of value, signalling the possibility that these systems interact. Because of its poor temporal resolution, fMRI risks confounding reward prediction errors with other feedback-related neural activity. In the present study, EEG was used to show the presence of both model-based and model-free reward prediction errors and their place in a temporal sequence of events including state prediction errors and action value updates. This demonstration of model-based prediction errors questions a long-held assumption that model-free and model-based learning are dissociated in the brain. Copyright © 2018 Elsevier Inc. All rights reserved.

Sequence modelling and an extensible data model for genomic database

Energy Technology Data Exchange (ETDEWEB)

Li, Peter Wei-Der [California Univ., San Francisco, CA (United States); Univ. of California, Berkeley, CA (United States)

1992-01-01

The Human Genome Project (HGP) plans to sequence the human genome by the beginning of the next century. It will generate DNA sequences of more than 10 billion bases and complex marker sequences (maps) of more than 100 million markers. All of these information will be stored in database management systems (DBMSs). However, existing data models do not have the abstraction mechanism for modelling sequences and existing DBMS`s do not have operations for complex sequences. This work addresses the problem of sequence modelling in the context of the HGP and the more general problem of an extensible object data model that can incorporate the sequence model as well as existing and future data constructs and operators. First, we proposed a general sequence model that is application and implementation independent. This model is used to capture the sequence information found in the HGP at the conceptual level. In addition, abstract and biological sequence operators are defined for manipulating the modelled sequences. Second, we combined many features of semantic and object oriented data models into an extensible framework, which we called the ``Extensible Object Model``, to address the need of a modelling framework for incorporating the sequence data model with other types of data constructs and operators. This framework is based on the conceptual separation between constructors and constraints. We then used this modelling framework to integrate the constructs for the conceptual sequence model. The Extensible Object Model is also defined with a graphical representation, which is useful as a tool for database designers. Finally, we defined a query language to support this model and implement the query processor to demonstrate the feasibility of the extensible framework and the usefulness of the conceptual sequence model.

Sequence modelling and an extensible data model for genomic database

Energy Technology Data Exchange (ETDEWEB)

Li, Peter Wei-Der (California Univ., San Francisco, CA (United States) Lawrence Berkeley Lab., CA (United States))

1992-01-01

The Human Genome Project (HGP) plans to sequence the human genome by the beginning of the next century. It will generate DNA sequences of more than 10 billion bases and complex marker sequences (maps) of more than 100 million markers. All of these information will be stored in database management systems (DBMSs). However, existing data models do not have the abstraction mechanism for modelling sequences and existing DBMS's do not have operations for complex sequences. This work addresses the problem of sequence modelling in the context of the HGP and the more general problem of an extensible object data model that can incorporate the sequence model as well as existing and future data constructs and operators. First, we proposed a general sequence model that is application and implementation independent. This model is used to capture the sequence information found in the HGP at the conceptual level. In addition, abstract and biological sequence operators are defined for manipulating the modelled sequences. Second, we combined many features of semantic and object oriented data models into an extensible framework, which we called the Extensible Object Model'', to address the need of a modelling framework for incorporating the sequence data model with other types of data constructs and operators. This framework is based on the conceptual separation between constructors and constraints. We then used this modelling framework to integrate the constructs for the conceptual sequence model. The Extensible Object Model is also defined with a graphical representation, which is useful as a tool for database designers. Finally, we defined a query language to support this model and implement the query processor to demonstrate the feasibility of the extensible framework and the usefulness of the conceptual sequence model.

Modelling of JET diagnostics using Bayesian Graphical Models

Energy Technology Data Exchange (ETDEWEB)

Svensson, J. [IPP Greifswald, Greifswald (Germany); Ford, O. [Imperial College, London (United Kingdom); McDonald, D.; Hole, M.; Nessi, G. von; Meakins, A.; Brix, M.; Thomsen, H.; Werner, A.; Sirinelli, A.

2011-07-01

The mapping between physics parameters (such as densities, currents, flows, temperatures etc) defining the plasma 'state' under a given model and the raw observations of each plasma diagnostic will 1) depend on the particular physics model used, 2) is inherently probabilistic, from uncertainties on both observations and instrumental aspects of the mapping, such as calibrations, instrument functions etc. A flexible and principled way of modelling such interconnected probabilistic systems is through so called Bayesian graphical models. Being an amalgam between graph theory and probability theory, Bayesian graphical models can simulate the complex interconnections between physics models and diagnostic observations from multiple heterogeneous diagnostic systems, making it relatively easy to optimally combine the observations from multiple diagnostics for joint inference on parameters of the underlying physics model, which in itself can be represented as part of the graph. At JET about 10 diagnostic systems have to date been modelled in this way, and has lead to a number of new results, including: the reconstruction of the flux surface topology and q-profiles without any specific equilibrium assumption, using information from a number of different diagnostic systems; profile inversions taking into account the uncertainties in the flux surface positions and a substantial increase in accuracy of JET electron density and temperature profiles, including improved pedestal resolution, through the joint analysis of three diagnostic systems. It is believed that the Bayesian graph approach could potentially be utilised for very large sets of diagnostics, providing a generic data analysis framework for nuclear fusion experiments, that would be able to optimally utilize the information from multiple diagnostics simultaneously, and where the explicit graph representation of the connections to underlying physics models could be used for sophisticated model testing. This

Culturicon model: A new model for cultural-based emoticon

Science.gov (United States)

Zukhi, Mohd Zhafri Bin Mohd; Hussain, Azham

2017-10-01

Emoticons are popular among distributed collective interaction user in expressing their emotion, gestures and actions. Emoticons have been proved to be able to avoid misunderstanding of the message, attention saving and improved the communications among different native speakers. However, beside the benefits that emoticons can provide, the study regarding emoticons in cultural perspective is still lacking. As emoticons are crucial in global communication, culture should be one of the extensively research aspect in distributed collective interaction. Therefore, this study attempt to explore and develop model for cultural-based emoticon. Three cultural models that have been used in Human-Computer Interaction were studied which are the Hall Culture Model, Trompenaars and Hampden Culture Model and Hofstede Culture Model. The dimensions from these three models will be used in developing the proposed cultural-based emoticon model.

Business Models and Business Model Innovation

DEFF Research Database (Denmark)

Foss, Nicolai J.; Saebi, Tina

2018-01-01

While research on business models and business model innovation continue to exhibit growth, the field is still, even after more than two decades of research, characterized by a striking lack of cumulative theorizing and an opportunistic borrowing of more or less related ideas from neighbouring...

The bumper bundle book of modelling NLP modelling made simple

CERN Document Server

Burgess, Fran

2014-01-01

A Neurolinguistic Programming textbook which focusses on the core activity of NLP - modelling. It covers the thinking behind NLP modelling, presents an extensive range of modelling methodologies and skills, offers applications of modelling, and provides specific details for model and technique construction.

Anatomically accurate, finite model eye for optical modeling.

Science.gov (United States)

Liou, H L; Brennan, N A

1997-08-01

There is a need for a schematic eye that models vision accurately under various conditions such as refractive surgical procedures, contact lens and spectacle wear, and near vision. Here we propose a new model eye close to anatomical, biometric, and optical realities. This is a finite model with four aspheric refracting surfaces and a gradient-index lens. It has an equivalent power of 60.35 D and an axial length of 23.95 mm. The new model eye provides spherical aberration values within the limits of empirical results and predicts chromatic aberration for wavelengths between 380 and 750 nm. It provides a model for calculating optical transfer functions and predicting optical performance of the eye.

Ecological models and pesticide risk assessment: current modeling practice.

Science.gov (United States)

Schmolke, Amelie; Thorbek, Pernille; Chapman, Peter; Grimm, Volker

2010-04-01

Ecological risk assessments of pesticides usually focus on risk at the level of individuals, and are carried out by comparing exposure and toxicological endpoints. However, in most cases the protection goal is populations rather than individuals. On the population level, effects of pesticides depend not only on exposure and toxicity, but also on factors such as life history characteristics, population structure, timing of application, presence of refuges in time and space, and landscape structure. Ecological models can integrate such factors and have the potential to become important tools for the prediction of population-level effects of exposure to pesticides, thus allowing extrapolations, for example, from laboratory to field. Indeed, a broad range of ecological models have been applied to chemical risk assessment in the scientific literature, but so far such models have only rarely been used to support regulatory risk assessments of pesticides. To better understand the reasons for this situation, the current modeling practice in this field was assessed in the present study. The scientific literature was searched for relevant models and assessed according to nine characteristics: model type, model complexity, toxicity measure, exposure pattern, other factors, taxonomic group, risk assessment endpoint, parameterization, and model evaluation. The present study found that, although most models were of a high scientific standard, many of them would need modification before they are suitable for regulatory risk assessments. The main shortcomings of currently available models in the context of regulatory pesticide risk assessments were identified. When ecological models are applied to regulatory risk assessments, we recommend reviewing these models according to the nine characteristics evaluated here. (c) 2010 SETAC.

Model performance analysis and model validation in logistic regression

Directory of Open Access Journals (Sweden)

Rosa Arboretti Giancristofaro

2007-10-01

Full Text Available In this paper a new model validation procedure for a logistic regression model is presented. At first, we illustrate a brief review of different techniques of model validation. Next, we define a number of properties required for a model to be considered "good", and a number of quantitative performance measures. Lastly, we describe a methodology for the assessment of the performance of a given model by using an example taken from a management study.

Pharmacokinetic modeling of gentamicin in treatment of infective endocarditis: Model development and validation of existing models

Science.gov (United States)

van der Wijk, Lars; Proost, Johannes H.; Sinha, Bhanu; Touw, Daan J.

2017-01-01

Gentamicin shows large variations in half-life and volume of distribution (Vd) within and between individuals. Thus, monitoring and accurately predicting serum levels are required to optimize effectiveness and minimize toxicity. Currently, two population pharmacokinetic models are applied for predicting gentamicin doses in adults. For endocarditis patients the optimal model is unknown. We aimed at: 1) creating an optimal model for endocarditis patients; and 2) assessing whether the endocarditis and existing models can accurately predict serum levels. We performed a retrospective observational two-cohort study: one cohort to parameterize the endocarditis model by iterative two-stage Bayesian analysis, and a second cohort to validate and compare all three models. The Akaike Information Criterion and the weighted sum of squares of the residuals divided by the degrees of freedom were used to select the endocarditis model. Median Prediction Error (MDPE) and Median Absolute Prediction Error (MDAPE) were used to test all models with the validation dataset. We built the endocarditis model based on data from the modeling cohort (65 patients) with a fixed 0.277 L/h/70kg metabolic clearance, 0.698 (±0.358) renal clearance as fraction of creatinine clearance, and Vd 0.312 (±0.076) L/kg corrected lean body mass. External validation with data from 14 validation cohort patients showed a similar predictive power of the endocarditis model (MDPE -1.77%, MDAPE 4.68%) as compared to the intensive-care (MDPE -1.33%, MDAPE 4.37%) and standard (MDPE -0.90%, MDAPE 4.82%) models. All models acceptably predicted pharmacokinetic parameters for gentamicin in endocarditis patients. However, these patients appear to have an increased Vd, similar to intensive care patients. Vd mainly determines the height of peak serum levels, which in turn correlate with bactericidal activity. In order to maintain simplicity, we advise to use the existing intensive-care model in clinical practice to avoid

Pharmacokinetic modeling of gentamicin in treatment of infective endocarditis: Model development and validation of existing models.

Directory of Open Access Journals (Sweden)

Anna Gomes

Full Text Available Gentamicin shows large variations in half-life and volume of distribution (Vd within and between individuals. Thus, monitoring and accurately predicting serum levels are required to optimize effectiveness and minimize toxicity. Currently, two population pharmacokinetic models are applied for predicting gentamicin doses in adults. For endocarditis patients the optimal model is unknown. We aimed at: 1 creating an optimal model for endocarditis patients; and 2 assessing whether the endocarditis and existing models can accurately predict serum levels. We performed a retrospective observational two-cohort study: one cohort to parameterize the endocarditis model by iterative two-stage Bayesian analysis, and a second cohort to validate and compare all three models. The Akaike Information Criterion and the weighted sum of squares of the residuals divided by the degrees of freedom were used to select the endocarditis model. Median Prediction Error (MDPE and Median Absolute Prediction Error (MDAPE were used to test all models with the validation dataset. We built the endocarditis model based on data from the modeling cohort (65 patients with a fixed 0.277 L/h/70kg metabolic clearance, 0.698 (±0.358 renal clearance as fraction of creatinine clearance, and Vd 0.312 (±0.076 L/kg corrected lean body mass. External validation with data from 14 validation cohort patients showed a similar predictive power of the endocarditis model (MDPE -1.77%, MDAPE 4.68% as compared to the intensive-care (MDPE -1.33%, MDAPE 4.37% and standard (MDPE -0.90%, MDAPE 4.82% models. All models acceptably predicted pharmacokinetic parameters for gentamicin in endocarditis patients. However, these patients appear to have an increased Vd, similar to intensive care patients. Vd mainly determines the height of peak serum levels, which in turn correlate with bactericidal activity. In order to maintain simplicity, we advise to use the existing intensive-care model in clinical practice to

Viscoelastic Model for Lung Parenchyma for Multi-Scale Modeling of Respiratory System, Phase II: Dodecahedral Micro-Model

Energy Technology Data Exchange (ETDEWEB)

Freed, Alan D.; Einstein, Daniel R.; Carson, James P.; Jacob, Rick E.

2012-03-01

In the first year of this contractual effort a hypo-elastic constitutive model was developed and shown to have great potential in modeling the elastic response of parenchyma. This model resides at the macroscopic level of the continuum. In this, the second year of our support, an isotropic dodecahedron is employed as an alveolar model. This is a microscopic model for parenchyma. A hopeful outcome is that the linkage between these two scales of modeling will be a source of insight and inspiration that will aid us in the final year's activity: creating a viscoelastic model for parenchyma.

Ventilation Model

International Nuclear Information System (INIS)

Yang, H.

1999-01-01

The purpose of this analysis and model report (AMR) for the Ventilation Model is to analyze the effects of pre-closure continuous ventilation in the Engineered Barrier System (EBS) emplacement drifts and provide heat removal data to support EBS design. It will also provide input data (initial conditions, and time varying boundary conditions) for the EBS post-closure performance assessment and the EBS Water Distribution and Removal Process Model. The objective of the analysis is to develop, describe, and apply calculation methods and models that can be used to predict thermal conditions within emplacement drifts under forced ventilation during the pre-closure period. The scope of this analysis includes: (1) Provide a general description of effects and heat transfer process of emplacement drift ventilation. (2) Develop a modeling approach to simulate the impacts of pre-closure ventilation on the thermal conditions in emplacement drifts. (3) Identify and document inputs to be used for modeling emplacement ventilation. (4) Perform calculations of temperatures and heat removal in the emplacement drift. (5) Address general considerations of the effect of water/moisture removal by ventilation on the repository thermal conditions. The numerical modeling in this document will be limited to heat-only modeling and calculations. Only a preliminary assessment of the heat/moisture ventilation effects and modeling method will be performed in this revision. Modeling of moisture effects on heat removal and emplacement drift temperature may be performed in the future

Methodology for geometric modelling. Presentation and administration of site descriptive models; Metodik foer geometrisk modellering. Presentation och administration av platsbeskrivande modeller

Energy Technology Data Exchange (ETDEWEB)

Munier, Raymond [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden); Hermanson, Jan [Golder Associates (Sweden)

2001-03-01

This report presents a methodology to construct, visualise and present geoscientific descriptive models based on data from the site investigations, which the SKB currently performs, to build an underground nuclear waste disposal facility in Sweden. It is designed for interaction with SICADA (SKB:s site characterisation database) and RVS (SKB:s Rock Visualisation System). However, the concepts of the methodology are general and can be used with other tools capable of handling 3D geometries and parameters. The descriptive model is intended to be an instrument where site investigation data from all disciplines are put together to form a comprehensive visual interpretation of the studied rock mass. The methodology has four main components: 1. Construction of a geometrical model of the interpreted main structures at the site. 2. Description of the geoscientific characteristics of the structures. 3. Description and geometrical implementation of the geometric uncertainties in the interpreted model structures. 4. Quality system for the handling of the geometrical model, its associated database and some aspects of the technical auditing. The geometrical model forms a basis for understanding the main elements and structures of the investigated site. Once the interpreted geometries are in place in the model, the system allows for adding descriptive and quantitative data to each modelled object through a system of intuitive menus. The associated database allows each geometrical object a complete quantitative description of all geoscientific disciplines, variabilities, uncertainties in interpretation and full version history. The complete geometrical model and its associated database of object descriptions are to be recorded in a central quality system. Official, new and old versions of the model are administered centrally in order to have complete quality assurance of each step in the interpretation process. The descriptive model is a cornerstone in the understanding of the

Coupled model of INM-IO global ocean model, CICE sea ice model and SCM OIAS framework

Science.gov (United States)

Bayburin, Ruslan; Rashit, Ibrayev; Konstantin, Ushakov; Vladimir, Kalmykov; Gleb, Dyakonov

2015-04-01

Status of coupled Arctic model of ocean and sea ice is presented. Model consists of INM IO global ocean component of high resolution, Los Alamos National Laboratory CICE sea ice model and a framework SCM OIAS for the ocean-ice-atmosphere-land coupled modeling on massively-parallel architectures. Model is currently under development at the Institute of Numerical Mathematics (INM), Hydrometeorological Center (HMC) and P.P. Shirshov Institute of Oceanology (IO). Model is aimed at modeling of intra-annual variability of hydrodynamics in Arctic and. The computational characteristics of the world ocean-sea ice coupled model governed by SCM OIAS are presented. The model is parallelized using MPI technologies and currently can use efficiently up to 5000 cores. Details of programming implementation, computational configuration and physical phenomena parametrization are analyzed in terms of intercoupling complex. Results of five year computational experiment of sea ice, snow and ocean state evolution in Arctic region on tripole grid with horizontal resolution of 3-5 kilometers, closed by atmospheric forcing field from repeating "normal" annual course taken from CORE1 experiment data base are presented and analyzed in terms of the state of vorticity and warm Atlantic water expansion.

Models of breast cancer: quo vadis, animal modeling?

International Nuclear Information System (INIS)

Wagner, Kay-Uwe

2004-01-01

Rodent models for breast cancer have for many decades provided unparalleled insights into cellular and molecular aspects of neoplastic transformation and tumorigenesis. Despite recent improvements in the fidelity of genetically engineered mice, rodent models are still being criticized by many colleagues for not being 'authentic' enough to the human disease. Motives for this criticism are manifold and range from a very general antipathy against the rodent model system to well-founded arguments that highlight physiological variations between species. Newly proposed differences in genetic pathways that cause cancer in humans and mice invigorated the ongoing discussion about the legitimacy of the murine system to model the human disease. The present commentary intends to stimulate a debate on this subject by providing the background about new developments in animal modeling, by disputing suggested limitations of genetically engineered mice, and by discussing improvements but also ambiguous expectations on the authenticity of xenograft models to faithfully mimic the human disease

Mathematical modelling

CERN Document Server

2016-01-01

This book provides a thorough introduction to the challenge of applying mathematics in real-world scenarios. Modelling tasks rarely involve well-defined categories, and they often require multidisciplinary input from mathematics, physics, computer sciences, or engineering. In keeping with this spirit of modelling, the book includes a wealth of cross-references between the chapters and frequently points to the real-world context. The book combines classical approaches to modelling with novel areas such as soft computing methods, inverse problems, and model uncertainty. Attention is also paid to the interaction between models, data and the use of mathematical software. The reader will find a broad selection of theoretical tools for practicing industrial mathematics, including the analysis of continuum models, probabilistic and discrete phenomena, and asymptotic and sensitivity analysis.

Empirical investigation on modeling solar radiation series with ARMA–GARCH models

International Nuclear Information System (INIS)

Sun, Huaiwei; Yan, Dong; Zhao, Na; Zhou, Jianzhong

2015-01-01

Highlights: • Apply 6 ARMA–GARCH(-M) models to model and forecast solar radiation. • The ARMA–GARCH(-M) models produce more accurate radiation forecasting than conventional methods. • Show that ARMA–GARCH-M models are more effective for forecasting solar radiation mean and volatility. • The ARMA–EGARCH-M is robust and the ARMA–sGARCH-M is very competitive. - Abstract: Simulation of radiation is one of the most important issues in solar utilization. Time series models are useful tools in the estimation and forecasting of solar radiation series and their changes. In this paper, the effectiveness of autoregressive moving average (ARMA) models with various generalized autoregressive conditional heteroskedasticity (GARCH) processes, namely ARMA–GARCH models are evaluated for their effectiveness in radiation series. Six different GARCH approaches, which contain three different ARMA–GARCH models and corresponded GARCH in mean (ARMA–GARCH-M) models, are applied in radiation data sets from two representative climate stations in China. Multiple evaluation metrics of modeling sufficiency are used for evaluating the performances of models. The results show that the ARMA–GARCH(-M) models are effective in radiation series estimation. Both in fitting and prediction of radiation series, the ARMA–GARCH(-M) models show better modeling sufficiency than traditional models, while ARMA–EGARCH-M models are robustness in two sites and the ARMA–sGARCH-M models appear very competitive. Comparisons of statistical diagnostics and model performance clearly show that the ARMA–GARCH-M models make the mean radiation equations become more sufficient. It is recommended the ARMA–GARCH(-M) models to be the preferred method to use in the modeling of solar radiation series

Hydrogeological conceptual model development and numerical modelling using CONNECTFLOW, Forsmark modelling stage 2.3

Energy Technology Data Exchange (ETDEWEB)

Follin, Sven (SF GeoLogic AB, Taeby (Sweden)); Hartley, Lee; Jackson, Peter; Roberts, David (Serco TAP (United Kingdom)); Marsic, Niko (Kemakta Konsult AB, Stockholm (Sweden))

2008-05-15

Three versions of a site descriptive model (SDM) have been completed for the Forsmark area. Version 0 established the state of knowledge prior to the start of the site investigation programme. Version 1.1 was essentially a training exercise and was completed during 2004. Version 1.2 was a preliminary site description and concluded the initial site investigation work (ISI) in June 2005. Three modelling stages are planned for the complete site investigation work (CSI). These are labelled stage 2.1, 2.2 and 2.3, respectively. An important component of each of these stages is to address and continuously try to resolve discipline-specific uncertainties of importance for repository engineering and safety assessment. Stage 2.1 included an updated geological model for Forsmark and aimed to provide a feedback from the modelling working group to the site investigation team to enable completion of the site investigation work. Stage 2.2 described the conceptual understanding and the numerical modelling of the bedrock hydrogeology in the Forsmark area based on data freeze 2.2. The present report describes the modelling based on data freeze 2.3, which is the final data freeze in Forsmark. In comparison, data freeze 2.3 is considerably smaller than data freeze 2.2. Therefore, stage 2.3 deals primarily with model confirmation and uncertainty analysis, e.g. verification of important hypotheses made in stage 2.2 and the role of parameter uncertainty in the numerical modelling. On the whole, the work reported here constitutes an addendum to the work reported in stage 2.2. Two changes were made to the CONNECTFLOW code in stage 2.3. These serve to: 1) improve the representation of the hydraulic properties of the regolith, and 2) improve the conditioning of transmissivity of the deformation zones against single-hole hydraulic tests. The changes to the modelling of the regolith were made to improve the consistency with models made with the MIKE SHE code, which involved the introduction

The Use of Modeling-Based Text to Improve Students' Modeling Competencies

Science.gov (United States)

Jong, Jing-Ping; Chiu, Mei-Hung; Chung, Shiao-Lan

2015-01-01

This study investigated the effects of a modeling-based text on 10th graders' modeling competencies. Fifteen 10th graders read a researcher-developed modeling-based science text on the ideal gas law that included explicit descriptions and representations of modeling processes (i.e., model selection, model construction, model validation, model…

Model documentation Natural Gas Transmission and Distribution Model of the National Energy Modeling System. Volume 1

International Nuclear Information System (INIS)

1996-01-01

The Natural Gas Transmission and Distribution Model (NGTDM) of the National Energy Modeling System is developed and maintained by the Energy Information Administration (EIA), Office of Integrated Analysis and Forecasting. This report documents the archived version of the NGTDM that was used to produce the natural gas forecasts presented in the Annual Energy Outlook 1996, (DOE/EIA-0383(96)). The purpose of this report is to provide a reference document for model analysts, users, and the public that defines the objectives of the model, describes its basic approach, and provides detail on the methodology employed. Previously this report represented Volume I of a two-volume set. Volume II reported on model performance, detailing convergence criteria and properties, results of sensitivity testing, comparison of model outputs with the literature and/or other model results, and major unresolved issues

Model documentation Natural Gas Transmission and Distribution Model of the National Energy Modeling System. Volume 1

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-02-26

The Natural Gas Transmission and Distribution Model (NGTDM) of the National Energy Modeling System is developed and maintained by the Energy Information Administration (EIA), Office of Integrated Analysis and Forecasting. This report documents the archived version of the NGTDM that was used to produce the natural gas forecasts presented in the Annual Energy Outlook 1996, (DOE/EIA-0383(96)). The purpose of this report is to provide a reference document for model analysts, users, and the public that defines the objectives of the model, describes its basic approach, and provides detail on the methodology employed. Previously this report represented Volume I of a two-volume set. Volume II reported on model performance, detailing convergence criteria and properties, results of sensitivity testing, comparison of model outputs with the literature and/or other model results, and major unresolved issues.

Rotating universe models

International Nuclear Information System (INIS)

Tozini, A.V.

1984-01-01

A review is made of some properties of the rotating Universe models. Godel's model is identified as a generalized filted model. Some properties of new solutions of the Einstein's equations, which are rotating non-stationary Universe models, are presented and analyzed. These models have the Godel's model as a particular case. Non-stationary cosmological models are found which are a generalization of the Godel's metrics in an analogous way in which Friedmann is to the Einstein's model. (L.C.) [pt

Ground-water solute transport modeling using a three-dimensional scaled model

International Nuclear Information System (INIS)

Crider, S.S.

1987-01-01

Scaled models are used extensively in current hydraulic research on sediment transport and solute dispersion in free surface flows (rivers, estuaries), but are neglected in current ground-water model research. Thus, an investigation was conducted to test the efficacy of a three-dimensional scaled model of solute transport in ground water. No previous results from such a model have been reported. Experiments performed on uniform scaled models indicated that some historical problems (e.g., construction and scaling difficulties; disproportionate capillary rise in model) were partly overcome by using simple model materials (sand, cement and water), by restricting model application to selective classes of problems, and by physically controlling the effect of the model capillary zone. Results from these tests were compared with mathematical models. Model scaling laws were derived for ground-water solute transport and used to build a three-dimensional scaled model of a ground-water tritium plume in a prototype aquifer on the Savannah River Plant near Aiken, South Carolina. Model results compared favorably with field data and with a numerical model. Scaled models are recommended as a useful additional tool for prediction of ground-water solute transport

Nonintersecting string model and graphical approach: equivalence with a Potts model

International Nuclear Information System (INIS)

Perk, J.H.H.; Wu, F.Y.

1986-01-01

Using a graphical method the authors establish the exact equivalence of the partition function of a q-state nonintersecting string (NIS) model on an arbitrary planar, even-valenced lattice with that of a q 2 -state Potts model on a relaxed lattice. The NIS model considered in this paper is one in which the vertex weights are expressible as sums of those of basic vertex types, and the resulting Potts model generally has multispin interactions. For the square and Kagome lattices this leads to the equivalence of a staggered NIS model with Potts models with anisotropic pair interactions, indicating that these NIS models have a first-order transition for q greater than 2. For the triangular lattice the NIS model turns out to be the five-vertex model of Wu and Lin and it relates to a Potts model with two- and three-site interactions. The most general model the authors discuss is an oriented NIS model which contains the six-vertex model and the NIS models of Stroganov and Schultz as special cases

BioModels: expanding horizons to include more modelling approaches and formats.

Science.gov (United States)

Glont, Mihai; Nguyen, Tung V N; Graesslin, Martin; Hälke, Robert; Ali, Raza; Schramm, Jochen; Wimalaratne, Sarala M; Kothamachu, Varun B; Rodriguez, Nicolas; Swat, Maciej J; Eils, Jurgen; Eils, Roland; Laibe, Camille; Malik-Sheriff, Rahuman S; Chelliah, Vijayalakshmi; Le Novère, Nicolas; Hermjakob, Henning

2018-01-04

BioModels serves as a central repository of mathematical models representing biological processes. It offers a platform to make mathematical models easily shareable across the systems modelling community, thereby supporting model reuse. To facilitate hosting a broader range of model formats derived from diverse modelling approaches and tools, a new infrastructure for BioModels has been developed that is available at http://www.ebi.ac.uk/biomodels. This new system allows submitting and sharing of a wide range of models with improved support for formats other than SBML. It also offers a version-control backed environment in which authors and curators can work collaboratively to curate models. This article summarises the features available in the current system and discusses the potential benefit they offer to the users over the previous system. In summary, the new portal broadens the scope of models accepted in BioModels and supports collaborative model curation which is crucial for model reproducibility and sharing. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.

Correlation between the model accuracy and model-based SOC estimation

International Nuclear Information System (INIS)

Wang, Qianqian; Wang, Jiao; Zhao, Pengju; Kang, Jianqiang; Yan, Few; Du, Changqing

2017-01-01

State-of-charge (SOC) estimation is a core technology for battery management systems. Considerable progress has been achieved in the study of SOC estimation algorithms, especially the algorithm on the basis of Kalman filter to meet the increasing demand of model-based battery management systems. The Kalman filter weakens the influence of white noise and initial error during SOC estimation but cannot eliminate the existing error of the battery model itself. As such, the accuracy of SOC estimation is directly related to the accuracy of the battery model. Thus far, the quantitative relationship between model accuracy and model-based SOC estimation remains unknown. This study summarizes three equivalent circuit lithium-ion battery models, namely, Thevenin, PNGV, and DP models. The model parameters are identified through hybrid pulse power characterization test. The three models are evaluated, and SOC estimation conducted by EKF-Ah method under three operating conditions are quantitatively studied. The regression and correlation of the standard deviation and normalized RMSE are studied and compared between the model error and the SOC estimation error. These parameters exhibit a strong linear relationship. Results indicate that the model accuracy affects the SOC estimation accuracy mainly in two ways: dispersion of the frequency distribution of the error and the overall level of the error. On the basis of the relationship between model error and SOC estimation error, our study provides a strategy for selecting a suitable cell model to meet the requirements of SOC precision using Kalman filter.

Simulation Model of Membrane Gas Separator Using Aspen Custom Modeler

Energy Technology Data Exchange (ETDEWEB)

Song, Dong-keun [Korea Institute of Machinery and Materials, Daejeon (Korea, Republic of); Shin, Gahui; Yun, Jinwon; Yu, Sangseok [Chungnam Nat’l Univ., Daejeon (Korea, Republic of)

2016-12-15

Membranes are used to separate pure gas from gas mixtures. In this study, three different types of mass transport through a membrane were developed in order to investigate the gas separation capabilities of a membrane. The three different models typically used are a lumped model, a multi-cell model, and a discretization model. Despite the multi-cell model producing similar results to a discretization model, the discretization model was selected for this investigation, due to the cell number dependence of a multi-cell model. The mass transport model was then used to investigate the effects of pressure difference, flow rate, total exposed area, and permeability. The results showed that the pressure difference increased with the stage cut, but the selectivity was a trade-off for the increasing pressure difference. Additionally, even though permeability is an important parameter, the selectivity and stage cut of the membrane converged as permeability increased.

Mathematical modelling

DEFF Research Database (Denmark)

Blomhøj, Morten

2004-01-01

Developing competences for setting up, analysing and criticising mathematical models are normally seen as relevant only from and above upper secondary level. The general belief among teachers is that modelling activities presuppose conceptual understanding of the mathematics involved. Mathematical...... roots for the construction of important mathematical concepts. In addition competences for setting up, analysing and criticising modelling processes and the possible use of models is a formative aim in this own right for mathematics teaching in general education. The paper presents a theoretical...... modelling, however, can be seen as a practice of teaching that place the relation between real life and mathematics into the centre of teaching and learning mathematics, and this is relevant at all levels. Modelling activities may motivate the learning process and help the learner to establish cognitive...

Simple Models for the Dynamic Modeling of Rotating Tires

Directory of Open Access Journals (Sweden)

J.C. Delamotte

2008-01-01

Full Text Available Large Finite Element (FE models of tires are currently used to predict low frequency behavior and to obtain dynamic model coefficients used in multi-body models for riding and comfort. However, to predict higher frequency behavior, which may explain irregular wear, critical rotating speeds and noise radiation, FE models are not practical. Detailed FE models are not adequate for optimization and uncertainty predictions either, as in such applications the dynamic solution must be computed a number of times. Therefore, there is a need for simpler models that can capture the physics of the tire and be used to compute the dynamic response with a low computational cost. In this paper, the spectral (or continuous element approach is used to derive such a model. A circular beam spectral element that takes into account the string effect is derived, and a method to simulate the response to a rotating force is implemented in the frequency domain. The behavior of a circular ring under different internal pressures is investigated using modal and frequency/wavenumber representations. Experimental results obtained with a real untreaded truck tire are presented and qualitatively compared with the simple model predictions with good agreement. No attempt is made to obtain equivalent parameters for the simple model from the real tire results. On the other hand, the simple model fails to represent the correct variation of the quotient of the natural frequency by the number of circumferential wavelengths with the mode count. Nevertheless, some important features of the real tire dynamic behavior, such as the generation of standing waves and part of the frequency/wavenumber behavior, can be investigated using the proposed simplified model.

BAYESIAN MODELS FOR SPECIES DISTRIBUTION MODELLING WITH ONLY-PRESENCE RECORDS

Directory of Open Access Journals (Sweden)

Bartolo de Jesús Villar-Hernández

2015-08-01

Full Text Available One of the central issues in ecology is the study of geographical distribution of species of flora and fauna through Species Distribution Models (SDM. Recently, scientific interest has focused on presence-only records. Two recent approaches have been proposed for this problem: a model based on maximum likelihood method (Maxlike and an inhomogeneous poisson process model (IPP. In this paper we discussed two bayesian approaches called MaxBayes and IPPBayes based on Maxlike and IPP model, respectively. To illustrate these proposals, we implemented two study examples: (1 both models were implemented on a simulated dataset, and (2 we modeled the potencial distribution of genus Dalea in the Tehuacan-Cuicatlán biosphere reserve with both models, the results was compared with that of Maxent. The results show that both models, MaxBayes and IPPBayes, are viable alternatives when species distribution are modeled with only-presence records. For simulated dataset, MaxBayes achieved prevalence estimation, even when the number of records was small. In the real dataset example, both models predict similar potential distributions like Maxent does. Â

Modeling of the Global Water Cycle - Analytical Models

Science.gov (United States)

Yongqiang Liu; Roni Avissar

2005-01-01

Both numerical and analytical models of coupled atmosphere and its underlying ground components (land, ocean, ice) are useful tools for modeling the global and regional water cycle. Unlike complex three-dimensional climate models, which need very large computing resources and involve a large number of complicated interactions often difficult to interpret, analytical...

Equivalent Dynamic Models.

Science.gov (United States)

Molenaar, Peter C M

2017-01-01

Equivalences of two classes of dynamic models for weakly stationary multivariate time series are discussed: dynamic factor models and autoregressive models. It is shown that exploratory dynamic factor models can be rotated, yielding an infinite set of equivalent solutions for any observed series. It also is shown that dynamic factor models with lagged factor loadings are not equivalent to the currently popular state-space models, and that restriction of attention to the latter type of models may yield invalid results. The known equivalent vector autoregressive model types, standard and structural, are given a new interpretation in which they are conceived of as the extremes of an innovating type of hybrid vector autoregressive models. It is shown that consideration of hybrid models solves many problems, in particular with Granger causality testing.

Applied stochastic modelling

CERN Document Server

Morgan, Byron JT; Tanner, Martin Abba; Carlin, Bradley P

2008-01-01

Introduction and Examples Introduction Examples of data sets Basic Model Fitting Introduction Maximum-likelihood estimation for a geometric model Maximum-likelihood for the beta-geometric model Modelling polyspermy Which model? What is a model for? Mechanistic models Function Optimisation Introduction MATLAB: graphs and finite differences Deterministic search methods Stochastic search methods Accuracy and a hybrid approach Basic Likelihood ToolsIntroduction Estimating standard errors and correlations Looking at surfaces: profile log-likelihoods Confidence regions from profiles Hypothesis testing in model selectionScore and Wald tests Classical goodness of fit Model selection biasGeneral Principles Introduction Parameterisation Parameter redundancy Boundary estimates Regression and influence The EM algorithm Alternative methods of model fitting Non-regular problemsSimulation Techniques Introduction Simulating random variables Integral estimation Verification Monte Carlo inference Estimating sampling distributi...

From spiking neuron models to linear-nonlinear models.

Science.gov (United States)

Ostojic, Srdjan; Brunel, Nicolas

2011-01-20

Neurons transform time-varying inputs into action potentials emitted stochastically at a time dependent rate. The mapping from current input to output firing rate is often represented with the help of phenomenological models such as the linear-nonlinear (LN) cascade, in which the output firing rate is estimated by applying to the input successively a linear temporal filter and a static non-linear transformation. These simplified models leave out the biophysical details of action potential generation. It is not a priori clear to which extent the input-output mapping of biophysically more realistic, spiking neuron models can be reduced to a simple linear-nonlinear cascade. Here we investigate this question for the leaky integrate-and-fire (LIF), exponential integrate-and-fire (EIF) and conductance-based Wang-Buzsáki models in presence of background synaptic activity. We exploit available analytic results for these models to determine the corresponding linear filter and static non-linearity in a parameter-free form. We show that the obtained functions are identical to the linear filter and static non-linearity determined using standard reverse correlation analysis. We then quantitatively compare the output of the corresponding linear-nonlinear cascade with numerical simulations of spiking neurons, systematically varying the parameters of input signal and background noise. We find that the LN cascade provides accurate estimates of the firing rates of spiking neurons in most of parameter space. For the EIF and Wang-Buzsáki models, we show that the LN cascade can be reduced to a firing rate model, the timescale of which we determine analytically. Finally we introduce an adaptive timescale rate model in which the timescale of the linear filter depends on the instantaneous firing rate. This model leads to highly accurate estimates of instantaneous firing rates.

Business Model Innovation

OpenAIRE

Dodgson, Mark; Gann, David; Phillips, Nelson; Massa, Lorenzo; Tucci, Christopher

2014-01-01

The chapter offers a broad review of the literature at the nexus between Business Models and innovation studies, and examines the notion of Business Model Innovation in three different situations: Business Model Design in newly formed organizations, Business Model Reconfiguration in incumbent firms, and Business Model Innovation in the broad context of sustainability. Tools and perspectives to make sense of Business Models and support managers and entrepreneurs in dealing with Business Model ...

IHY Modeling Support at the Community Coordinated Modeling Center

Science.gov (United States)

Chulaki, A.; Hesse, Michael; Kuznetsova, Masha; MacNeice, P.; Rastaetter, L.

2005-01-01

The Community Coordinated Modeling Center (CCMC) is a US inter-agency activity aiming at research in support of the generation of advanced space weather models. As one of its main functions, the CCMC provides to researchers the use of space science models, even if they are not model owners themselves. In particular, the CCMC provides to the research community the execution of "runs-onrequest" for specific events of interest to space science researchers. Through this activity and the concurrent development of advanced visualization tools, CCMC provides, to the general science community, unprecedented access to a large number of state-of-the-art research models. CCMC houses models that cover the entire domain from the Sun to the Earth. In this presentation, we will provide an overview of CCMC modeling services that are available to support activities during the International Heliospheric Year. In order to tailor CCMC activities to IHY needs, we will also invite community input into our IHY planning activities.

A probabilistic graphical model based stochastic input model construction

International Nuclear Information System (INIS)

Wan, Jiang; Zabaras, Nicholas

2014-01-01

Model reduction techniques have been widely used in modeling of high-dimensional stochastic input in uncertainty quantification tasks. However, the probabilistic modeling of random variables projected into reduced-order spaces presents a number of computational challenges. Due to the curse of dimensionality, the underlying dependence relationships between these random variables are difficult to capture. In this work, a probabilistic graphical model based approach is employed to learn the dependence by running a number of conditional independence tests using observation data. Thus a probabilistic model of the joint PDF is obtained and the PDF is factorized into a set of conditional distributions based on the dependence structure of the variables. The estimation of the joint PDF from data is then transformed to estimating conditional distributions under reduced dimensions. To improve the computational efficiency, a polynomial chaos expansion is further applied to represent the random field in terms of a set of standard random variables. This technique is combined with both linear and nonlinear model reduction methods. Numerical examples are presented to demonstrate the accuracy and efficiency of the probabilistic graphical model based stochastic input models. - Highlights: • Data-driven stochastic input models without the assumption of independence of the reduced random variables. • The problem is transformed to a Bayesian network structure learning problem. • Examples are given in flows in random media

Petroleum Market Model of the National Energy Modeling System

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-01-01

The purpose of this report is to define the objectives of the Petroleum Market Model (PMM), describe its basic approach, and provide detail on how it works. This report is intended as a reference document for model analysts, users, and the public. The PMM models petroleum refining activities, the marketing of petroleum products to consumption regions. The production of natural gas liquids in gas processing plants, and domestic methanol production. The PMM projects petroleum product prices and sources of supply for meeting petroleum product demand. The sources of supply include crude oil, both domestic and imported; other inputs including alcohols and ethers; natural gas plant liquids production; petroleum product imports; and refinery processing gain. In addition, the PMM estimates domestic refinery capacity expansion and fuel consumption. Product prices are estimated at the Census division level and much of the refining activity information is at the Petroleum Administration for Defense (PAD) District level. This report is organized as follows: Chapter 2, Model Purpose; Chapter 3, Model Overview and Rationale; Chapter 4, Model Structure; Appendix A, Inventory of Input Data, Parameter Estimates, and Model Outputs; Appendix B, Detailed Mathematical Description of the Model; Appendix C, Bibliography; Appendix D, Model Abstract; Appendix E, Data Quality; Appendix F, Estimation methodologies; Appendix G, Matrix Generator documentation; Appendix H, Historical Data Processing; and Appendix I, Biofuels Supply Submodule.

Petroleum Market Model of the National Energy Modeling System

International Nuclear Information System (INIS)

1997-01-01

The purpose of this report is to define the objectives of the Petroleum Market Model (PMM), describe its basic approach, and provide detail on how it works. This report is intended as a reference document for model analysts, users, and the public. The PMM models petroleum refining activities, the marketing of petroleum products to consumption regions. The production of natural gas liquids in gas processing plants, and domestic methanol production. The PMM projects petroleum product prices and sources of supply for meeting petroleum product demand. The sources of supply include crude oil, both domestic and imported; other inputs including alcohols and ethers; natural gas plant liquids production; petroleum product imports; and refinery processing gain. In addition, the PMM estimates domestic refinery capacity expansion and fuel consumption. Product prices are estimated at the Census division level and much of the refining activity information is at the Petroleum Administration for Defense (PAD) District level. This report is organized as follows: Chapter 2, Model Purpose; Chapter 3, Model Overview and Rationale; Chapter 4, Model Structure; Appendix A, Inventory of Input Data, Parameter Estimates, and Model Outputs; Appendix B, Detailed Mathematical Description of the Model; Appendix C, Bibliography; Appendix D, Model Abstract; Appendix E, Data Quality; Appendix F, Estimation methodologies; Appendix G, Matrix Generator documentation; Appendix H, Historical Data Processing; and Appendix I, Biofuels Supply Submodule

Modeling influenza-like illnesses through composite compartmental models

Science.gov (United States)

Levy, Nir; , Michael, Iv; Yom-Tov, Elad

2018-03-01

Epidemiological models for the spread of pathogens in a population are usually only able to describe a single pathogen. This makes their application unrealistic in cases where multiple pathogens with similar symptoms are spreading concurrently within the same population. Here we describe a method which makes possible the application of multiple single-strain models under minimal conditions. As such, our method provides a bridge between theoretical models of epidemiology and data-driven approaches for modeling of influenza and other similar viruses. Our model extends the Susceptible-Infected-Recovered model to higher dimensions, allowing the modeling of a population infected by multiple viruses. We further provide a method, based on an overcomplete dictionary of feasible realizations of SIR solutions, to blindly partition the time series representing the number of infected people in a population into individual components, each representing the effect of a single pathogen. We demonstrate the applicability of our proposed method on five years of seasonal influenza-like illness (ILI) rates, estimated from Twitter data. We demonstrate that our method describes, on average, 44% of the variance in the ILI time series. The individual infectious components derived from our model are matched to known viral profiles in the populations, which we demonstrate matches that of independently collected epidemiological data. We further show that the basic reproductive numbers (R 0) of the matched components are in range known for these pathogens. Our results suggest that the proposed method can be applied to other pathogens and geographies, providing a simple method for estimating the parameters of epidemics in a population.

Calibrated Properties Model

International Nuclear Information System (INIS)

Ahlers, C.; Liu, H.

2000-01-01

The purpose of this Analysis/Model Report (AMR) is to document the Calibrated Properties Model that provides calibrated parameter sets for unsaturated zone (UZ) flow and transport process models for the Yucca Mountain Site Characterization Project (YMP). This work was performed in accordance with the ''AMR Development Plan for U0035 Calibrated Properties Model REV00. These calibrated property sets include matrix and fracture parameters for the UZ Flow and Transport Model (UZ Model), drift seepage models, drift-scale and mountain-scale coupled-processes models, and Total System Performance Assessment (TSPA) models as well as Performance Assessment (PA) and other participating national laboratories and government agencies. These process models provide the necessary framework to test conceptual hypotheses of flow and transport at different scales and predict flow and transport behavior under a variety of climatic and thermal-loading conditions

Modeling the Frequency of Cyclists’ Red-Light Running Behavior Using Bayesian PG Model and PLN Model

Directory of Open Access Journals (Sweden)

Yao Wu

2016-01-01

Full Text Available Red-light running behaviors of bicycles at signalized intersection lead to a large number of traffic conflicts and high collision potentials. The primary objective of this study is to model the cyclists’ red-light running frequency within the framework of Bayesian statistics. Data was collected at twenty-five approaches at seventeen signalized intersections. The Poisson-gamma (PG and Poisson-lognormal (PLN model were developed and compared. The models were validated using Bayesian p values based on posterior predictive checking indicators. It was found that the two models have a good fit of the observed cyclists’ red-light running frequency. Furthermore, the PLN model outperformed the PG model. The model estimated results showed that the amount of cyclists’ red-light running is significantly influenced by bicycle flow, conflict traffic flow, pedestrian signal type, vehicle speed, and e-bike rate. The validation result demonstrated the reliability of the PLN model. The research results can help transportation professionals to predict the expected amount of the cyclists’ red-light running and develop effective guidelines or policies to reduce red-light running frequency of bicycles at signalized intersections.

An improved interfacial bonding model for material interface modeling

Science.gov (United States)

Lin, Liqiang; Wang, Xiaodu; Zeng, Xiaowei

2016-01-01

An improved interfacial bonding model was proposed from potential function point of view to investigate interfacial interactions in polycrystalline materials. It characterizes both attractive and repulsive interfacial interactions and can be applied to model different material interfaces. The path dependence of work-of-separation study indicates that the transformation of separation work is smooth in normal and tangential direction and the proposed model guarantees the consistency of the cohesive constitutive model. The improved interfacial bonding model was verified through a simple compression test in a standard hexagonal structure. The error between analytical solutions and numerical results from the proposed model is reasonable in linear elastic region. Ultimately, we investigated the mechanical behavior of extrafibrillar matrix in bone and the simulation results agreed well with experimental observations of bone fracture. PMID:28584343

Modelling freight transport

NARCIS (Netherlands)

Tavasszy, L.A.; Jong, G. de

2014-01-01

Freight Transport Modelling is a unique new reference book that provides insight into the state-of-the-art of freight modelling. Focusing on models used to support public transport policy analysis, Freight Transport Modelling systematically introduces the latest freight transport modelling

Adhesive contact: from atomistic model to continuum model

International Nuclear Information System (INIS)

Fan Kang-Qi; Jia Jian-Yuan; Zhu Ying-Min; Zhang Xiu-Yan

2011-01-01

Two types of Lennard-Jones potential are widely used in modeling adhesive contacts. However, the relationships between the parameters of the two types of Lennard-Jones potential are not well defined. This paper employs a self-consistent method to derive the Lennard-Jones surface force law from the interatomic Lennard-Jones potential with emphasis on the relationships between the parameters. The effect of using correct parameters in the adhesion models is demonstrated in single sphere-flat contact via continuum models and an atomistic model. Furthermore, the adhesion hysteresis behaviour is investigated, and the S-shaped force-distance relation is revealed by the atomistic model. It shows that the adhesion hysteresis loop is generated by the jump-to-contact and jump-off-contact, which are illustrated by the S-shaped force-distance curve. (atomic and molecular physics)