Thermal Efficiency of Trombe Wall in the South Facade of a Frame Building

The article presents the possibility of using a mass collector-storage wall (CSW), integrated into the structure of a building with a light skeleton structure. The considered system is a proposal for an energy-saving solution that can be used in buildings with various utility purposes. The article presents the results of experimental tests of a collector-storage wall mounted in the space of the skeleton structure of the southern facade of a building for the period of one year, as well as the results of numerical simulation. In the summer, the influence of the use of heat-insulating roller shutters on limiting overheating of the chamber interior was investigated. The effect of using the roller shutters is a reduction in the average value of the heat flux by about 77%. In the winter, the energy efficiency of the wall was tested. The obtained effect is energy consumption during the heating season at a level comparable to a wall with a traditional structure with a coefficient of U = 0.30 W/(m2K). The results of the numerical tests showed high agreement with the direct results, which provides a basis for the use of such simulations in further research on the search for the optimal structure of a collector-storage wall.

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Lamination effects on a 3D model of the magnetic core of power transformers

Open Physics ◽

10.1515/phys-2017-0124 ◽

2017 ◽

Vol 15 (1) ◽

pp. 997-1003

Author(s):

Antonio Poveda-Lerma ◽

Guillermo Serrano-Callergues ◽

Martin Riera-Guasp ◽

Manuel Pineda-Sanchez ◽

Ruben Puche-Panadero ◽

...

Keyword(s):

Magnetic Flux ◽

Flux Density ◽

Experimental Tests ◽

Butt Joint ◽

Magnetic Core ◽

Magnetic Flux Density ◽

Lap Joint ◽

3D Fem ◽

Average Value ◽

Depth Direction

AbstractIn this paper the lamination effect on the model of a power transformer’s core with stacked E-I structure is analyzed. The distribution of the magnetic flux in the laminations depends on the stacking method. In this work it is shown, using a 3D FEM model and an experimental prototype, that the non-uniform distribution of the flux in a laminated E-I core with alternate-lap joint stack increases substantially the average value of the magnetic flux density in the core, compared with a butt joint stack. Both the simulated model and the experimental tests show that the presence of constructive air-gaps in the E-I junctions gives rise to a zig-zag flux in the depth direction. This inter-lamination flux reduces the magnetic flux density in the I-pieces and increases substantially the magnetic flux density in the E-pieces, with highly saturated points that traditional 2D analysis cannot reproduce. The relation between the number of laminations included in the model, and the computational resourses needed to build it, is also evaluated in this work.

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Numerical Model of a Rotating Prism Wall: Its Validation and Predicted Device Performance for a Variety of Situations

Journal of Solar Energy Engineering ◽

10.1115/1.3268313 ◽

1989 ◽

Vol 111 (3) ◽

pp. 237-244 ◽

Cited By ~ 2

Author(s):

D. Faiman ◽

D. Feuermann ◽

M. Huleihil

Keyword(s):

Temperature Distribution ◽

Numerical Model ◽

Full Scale ◽

Device Performance ◽

Standard Design ◽

Trombe Wall ◽

Storage Wall

A numerical model has been developed which describes the temperature distribution as a function of time within the storage elements of a Rotating Prism Solar Storage Wall. The model is tested against data obtained from a full-scale Rotating Prism Wall at Sede Boqer in Israel, and found to reproduce the measured temperatures extremely well. The thus validated model is used to predict the performance of such devices in various kinds of climate and to compare this performance with that to be expected from a nonvented Trombe Wall of standard design. In all cases the Rotating Prism Wall is found to provide considerably more useful energy than a nonvented Trombe Wall.

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Observation on dominance of swells over wind-seas in the coastal waters of Gulf of Mannar, India

10.5194/os-2017-16 ◽

2017 ◽

Author(s):

M. M. Amrutha ◽

V. Sanil Kumar

Keyword(s):

Wave Height ◽

Coastal Waters ◽

Indian Subcontinent ◽

Sea Breeze ◽

Early Morning ◽

Gulf Of Mannar ◽

Study Region ◽

Average Value ◽

Late Evening ◽

One Year

Abstract. In coastal gulfs generally, predominance of wind-seas are expected. Waves measured at a location having a water depth of 15 m in the nearshore waters of Gulf of Mannar during one year period (1 May 2015 to 30 April 2016) is used to examine the predominance of wind-seas and swells through spectral characterization. The study shows that even though the location is in a gulf, the annual average value (~ 0.84 m) of the significant wave height at this area is comparable to that along the coastal waters of the Indian subcontinent, but the annual maximum value (~ 1.7 m) recorded is much less than that (3 to 5 m) observed in those regions. Also, large seasonal variations are not observed in the wave height. The waves of the study region are under the control of sea-breeze with the maximum in the late evening hours and the minimum in the early morning hours. 53 % of the surface height variance in the study area is a result of southeast and south swells and the remaining are the east and southeast wind-seas.

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Bomb 14C Recorded in Laminated Speleothems: Calculation of Dead Carbon Proportion

Radiocarbon ◽

10.1017/s0033822200040881 ◽

1997 ◽

Vol 39 (1) ◽

pp. 33-48 ◽

Cited By ~ 67

Author(s):

Dominique Genty ◽

Marc Massault

Keyword(s):

Forest Cover ◽

Open Systems ◽

Sampling Site ◽

Uncertainty Range ◽

Average Value ◽

Soil Zone ◽

Calcite Deposition ◽

The Dead ◽

Local Geology ◽

One Year

We performed radiocarbon measurements using accelerator mass spectrometry (AMS) on 6 stalagmites 3 stalactites and 7 seepage waters from four different caves in Southwest France and Belgium in order to calculate the dead carbon proportion (dcp). All the speleothems studied are modern and annually laminated, which offers the advantage of an accurate chronology, with better than one-year resolution. Coupled with the fact that very little calcite is necessary for an AMS measurement (between 1.5 and 7 yr of calcite deposit), we obtained dead carbon values within an uncertainty limit of ± 1.5%. Results show that the dead carbon proportion varies from 9.2% to 21.9% for calcite deposits and from 3.6% to 21.9% for water. In each sampling site, the dcp is homogeneous. Although the inter-site dcp varies by >11%, its average value of 15.5% ± 4.4 still lies within the uncertainty range of the accepted value of 15% ± 5 (dilution factor of 0.85 ± 0.5). We compare the average dcp of each site with the local geology, vegetation and climate. Given similar geology and temperature the highest dcp values are found under forest cover; dcp difference is up to 9%. However, the Belgian site, which is also under a forest shows a dcp very close to the dcp found under grassland sites of Southwest France, which proves that other unknown factors may play an important role in dissolution processes. Secondary calcite deposition and redissolution in the soil zone or more likely in the fracture system before reaching the cave itself could also explain the inter-site differences. The IAEA isotopic model (Pearson model adapted for open systems) is in good agreement with the measured activities.

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Effect of Work Attitude and Total Productive Maintenance on the Overall Equipment Effectiveness and Production Continuity

IRA-International Journal of Management & Social Sciences (ISSN 2455-2267) ◽

10.21013/jmss.v7.n3.p3 ◽

2017 ◽

Vol 7 (3) ◽

pp. 423

Author(s):

Puadi Haming ◽

Mahfud Nurnajamuddin ◽

Hamzah Hafied ◽

Serlin Serang

Keyword(s):

Work Experience ◽

Partial Least Square ◽

Least Square ◽

Total Productive Maintenance ◽

Work Attitude ◽

Average Value ◽

Mediating Role ◽

Endogenous Variables ◽

One Year ◽

The Impact

<div><p><em>This study aims to examine and analyze the impact of work attitude, Total Productive Maintenance (TPM) on the Overall Equipment Effectiveness (OEE) and production continuity and the other effect of Work Attitude and Total Productive Maintenance (TPM) on production continuity: The mediating role of Overall Equipment Effectiveness (OEE). The research was conducted at PT. Semen Tonasa i.e. units II to V unit which is the largest cement producer in eastern Indonesia. Withdrawal of respondents did with the criteria that only respondents yang having their respective sectors and who have work experience of at least one year were used as samples. Results of analysis Partial Least Square (PLS) Version 2.0.M3 used in analyzing the contribution of exogenous variables on endogenous variables directly, Sobel Test was used for pushing analyze the contribution of the indirect effect (mediation) whereas importance- performance analysis (IPA) to analogous interpret the relationship loading factor value and the average value. The results of this study provide evidence of work attitude has a positive and significant effect on the overall equipment effectiveness (OEE), total productive maintenance (TPM) has a positive and significant effect on overall equipment effectiveness (OEE), work attitude, total productive maintenance (TPM) and overall equipment effectiveness (OEE) positive and significant impact on production continuity.</em></p></div>

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Surface ablation variability of mountain glaciers of West Spitsbergen

Arctic and Antarctic Research ◽

10.30758/0555-2648-2019-65-4-438-448 ◽

2019 ◽

Vol 65 (4) ◽

pp. 438-448

Author(s):

O. R. Sidorova ◽

G. V. Tarasov ◽

S. R. Verkulich ◽

R. A. Chernov

Keyword(s):

Significant Contribution ◽

Climatic Conditions ◽

Altitude Range ◽

Model Calculations ◽

Average Value ◽

Mountain Glaciers ◽

Surface Ablation ◽

One Year ◽

West Spitsbergen ◽

Interannual Scale

Measurements of surface ablation in 2016–2018 on the neighboring glaciers Aldegondabreen, Austre and Vestre Grønfjordbreen (West Spitsbergen) revealed significant differences in its magnitude both within the same altitude zones for one year, and on an interannual scale. Comparison of the region’s common variations in climatic conditions (air temperature, rainfall) and ablation data showed a significant contribution of the following additional factors of melting: aspect, size, altitude range, surface slope, the rocky bordering of glaciers. The maximum ablation were measured on the Aldegondabreen (with the smallest area and altitude range), which has a northeastern aspect; the average value over three years of observations was 1947 mm w.e. Austre Grønfjordbreen and Vestre Grønfjordbreen had in 2016–2018 average ablation values 1512 and 1385 mm w.e., respectively. The largest Vestre Grønfjordbreen has the lowest values of average ablation also because it lies higher then neighboring glaciers. Interannual variations of mean ablation in the same altitudinal zones show: the minimum scatter of values for the Aldegondabreen (130–370 mm w.e.); higher scatter of values for the Austre Grønfjordbreen (200–450 mm w.e.); the maximum scatter of values for the Vestre Grønfjordbreen (from 400–600 mm w.e. in most altitude zones to 1000 mm w.e. at altitudes of 250–350 m). Due to the influence of additional factors, the maximum average ablation was observed on the Aldegondabreen in 2016, on the Vestre Grønfjordbreen in 2017, and on the Austre Grønfjordbreen in 2017 and 2018. The results of the study indicate the need to take into account the contribution of these factors to the ablation parameters of the region’s glaciers in model calculations, as well as the relevance of a detailed study of the distribution of solar radiation on glaciers.

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Cytoreductive surgery and hyperthermal intraperitoneal chemoperfusion in colorectal cancer and cancer of ovaries: our experience and perspectives of a new method

Klinicheskaia khirurgiia ◽

10.26779/2522-1396.2020.9-10.54 ◽

2020 ◽

Vol 87 (9-10) ◽

pp. 54-58

Author(s):

A. V. Malynovskyi ◽

V. V. Grubnik ◽

I. Z. Gladchuk

Keyword(s):

Colorectal Cancer ◽

Ovarian Cancer ◽

Intraoperative Complications ◽

Optimal Cytoreduction ◽

Women Patients ◽

Average Value ◽

Visceral Peritoneum ◽

One Year ◽

Intraperitoneal Chemoperfusion

Objective. Studying of results of the cytoreductive operations and hyperthermal intraperitoneal chemoperfusion application for treatment of canceromatosis in colorectal cancer and ovarian cancer. Materials and methods. In 10 patients, suffering colorectal cancer (6 men and 4 women) were performed peritonectomy, diathermo-ablation of implants, made from visceral peritoneum. Average value of the peritoneal canceromatosis index have constituted 18 (14 - 21). In 11 patients, suffering ovarian cancer, panhisterectomy, peritonectomy, omentectomy, and ablation of the visceral peritoneum implants was conducted. Median value of the peritoneal canceromatosis index was 16 (12 - 20). For hyperthermal intraperitoneal chemoperfusion oxaliplatin was used. Results. Complete and optimal cytoreduction (degree CC0-CC1 in accordance to classification of P. H. Sugarbaker) was achieved in 5 patients, while suboptimal one (degree CC2) - in 10, and nonoptimal (degree CC3) cytoreduction - in 6 patients. Intraoperative complications were absent. Postoperative complications have occurred in 5 (23.8%) patients: the wound infection, persisting ileus, episode of partial ileus. Of 10 patients, suffering colorectal cancer, 5 died in 9-12 mo. One-year barrier have had survived 45.5% patients. Of 11 women-patients, suffering ovarian cancer, 7 died in 6-24 mo. One-year barrier have had survived 36.4% women-patients. Conclusion. In patients, suffering colorectal cancer, the survival median was 12 mo, while in the women-patients, suffering ovarian cancer - 18 mo. Cytoreductive operations and hyperthermal intraperitoneal chemoperfusion constitute perspective method for the survival enhancement in patients, suffering canceromatosis, but only if their selection was organized.

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Electrical Generation of a Ground-Level Solar Thermoelectric Generator: Experimental Tests and One-Year Cycle Simulation

Energies ◽

10.3390/en13133407 ◽

2020 ◽

Vol 13 (13) ◽

pp. 3407

Author(s):

Eduard Massaguer ◽

Albert Massaguer ◽

Eudald Balló ◽

Ivan Ruiz Cózar ◽

Toni Pujol ◽

...

Keyword(s):

Output Power ◽

Thermoelectric Generator ◽

Experimental Tests ◽

Ground Level ◽

Weather Conditions ◽

Energy Generation ◽

Atmospheric Conditions ◽

Cycle Simulation ◽

One Year ◽

Electrical Generation

Solar thermoelectric generators (STEGs) are a promising technology to harvest energy for off-grid applications. A wide variety of STEG designs have been proposed with the aim of providing non-intermittent electrical generation. Here, we designed and tested a STEG 0.5 m long formed by nine commercial thermoelectric generator modules and located at ground level. Data were used to validate a numerical model that was employed to simulate a one-year cycle. Results confirmed the very high variability of energy generation during daylight time due to weather conditions. By contrast, energy generation during night was almost independent of atmospheric conditions. Annual variations of nighttime energy generation followed the trend of the daily averaged soil temperature at the bottom of the device. Nighttime electrical energy generation was 5.4 times smaller than the diurnal one in yearly averaged values. Mean energy generation values per day were 587 J d−1 (daylight time) and 110 J d−1 (nighttime). Total annual energy generation was 255 kJ. Mean electrical output power values during daylight and nighttime were 13.4 mW and 2.5 mW, respectively. Annual mean output power was 7.9 mW with a peak value of 79.8 mW.

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Trombe Wall Thermal Behavior and Energy Efficiency of a Light Steel Frame Compartment: Experimental and Numerical Assessments

Energies ◽

10.3390/en13112744 ◽

2020 ◽

Vol 13 (11) ◽

pp. 2744 ◽

Cited By ~ 1

Author(s):

Victor Lohmann ◽

Paulo Santos

Keyword(s):

Energy Efficiency ◽

Thermal Behavior ◽

Dynamic Models ◽

Renewable Energy Sources ◽

Weather Conditions ◽

Thermal Storage ◽

Steel Frame ◽

Trombe Wall ◽

Storage Wall ◽

Heating Energy Consumption

Buildings are seeking renewable energy sources (e.g., solar) and passive devices, such as Trombe walls. However, the thermal performance of Trombe walls depends on many factors. In this work, the thermal behavior and energy efficiency of a Trombe wall in a lightweight steel frame compartment were evaluated, making use of in situ measurements and numerical simulations. Measurements were performed inside two real scale experimental identical cubic modules, exposed to natural exterior weather conditions. Simulations were made using validated advanced dynamic models. The winter Trombe wall benefits were evaluated regarding indoor air temperature increase and heating energy reduction. Moreover, a thermal behavior parametric study was performed. Several comparisons were made: (1) Sunny and cloudy winter week thermal behavior; (2) Office and residential space use heating energy; (3) Two heating set-points (20 °C and 18 °C); (4) Thickness of the Trombe wall air cavity; (5) Thickness of the thermal storage wall; (6) Dimensions of the interior upper/lower vents; (7) Material of the thermal storage wall. It was found that a Trombe wall device could significantly improve the thermal behavior and reduce heating energy consumption. However, if not well designed and controlled (e.g., to mitigate nocturnal heat losses), the Trombe wall thermal and energy benefits could be insignificant and even disadvantageous.

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Pengaruh Ekspor, Pengeluaran Pemerintah, dan Angkatan Kerja yang Bekerja Terhadap Pertumbuhan Ekonomi di Kabupaten Tulungagung

EKONIKA Jurnal Ekonomi Universitas Kadiri ◽

10.30737/ekonika.v4i2.452 ◽

2019 ◽

Vol 4 (2) ◽

pp. 193

Author(s):

Endang Triwidyati ◽

Nining Purnamaningsih

Keyword(s):

Economic Growth ◽

Time Series ◽

Labor Force ◽

Government Spending ◽

Secondary Data ◽

Average Value ◽

One Year ◽

Definition Of ◽

Positive Effect ◽

Data Analysis Methods

Changes in the average value of economic activity from one year to another by taking the average at the same time" is a brief definition of economic growth. This study aims to determine the effect of exports, government spending and labor force working on economic growth in Tulungagung. The type of data used in this study is secondary data on exports, government spending and labor force working in 2008-2017 in the form of quantitative time series, with multiple linear analysis and classical assumption tests as data analysis methods. The results showed that (1) there was no significant positive effect of exports on Tulungagung's economic growth. (2) The effect of government spending on economic growth in Tulungagung is significantly positive. (3) The effect of the labor force working on economic growth from Tulungagung is positive insignificant. Perubahan nilai rata-rata dari kegiatan ekonomi dari tahun untuk satu periode ke periode yang lain dengan mengambil rata-ratanya dalam waktu yang sama” adalah definisi singkat dari pertumbuhan ekonomi. Penelitian ini bertujuan untuk mengetahui pengaruh ekspor, pengeluaran pemerintah dan angkatan kerja yang bekerja terhadap pertumbuhan ekonomi di Tulungagung. Jenis data yang digunakan dalam penelitian ini adalah data sekunder ekspor, pengeluaran pemerintah dan angkatan kerja yang bekerja pada tahun 2008-2017 dalam bentuk time series yang bersifat kuantitatif, dengan analisis linier berganda dan uji asumsi klasik sebagai metode analisis data. Hasil penelitian menunjukkan bahwa (1) tidak ada pengaruh positif yang signifikan dari ekspor terhadap pertumbuhan ekonomi Tulungagung. (2) Efek dari belanja pemerintah terhadap pertumbuhan ekonomi di Tulungagung positif signifikan. (3) Efek dari angkatan kerja yang bekerja dalam pertumbuhan ekonomi dari Tulungagung positif tidak signifikan.

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