Sensitivity Analysis of the Levelized Cost of Electricity for a Particle-Based CSP System

This study presents a sensitivity analysis of the LCOE for a particle-based system with the costs of the most current components. New models for the primary heat exchanger, thermal energy storage and tower are presented and used to establish lower and upper bounds for these three components. The rest of component costs such as particle cost, cavity cost and lift cost are set to lower and upper bounds estimating an uncertainty between 25% and 50%. Other relevant parameters related to lift and storage performance are also included in the analysis with the same uncertainty. This study also includes an upgrade to the receiver model by including the wind effect in the efficiency, which was not included in previous publications and may have a big impact in the system design. A parametric analysis shows the optimum values of solar multiple, storage hours, tower height and concentration ratio, and a probabilistic analysis provides a cumulative distribution function for a range of LCOE values. The results show that the LCOE could be below $0.06/kWh with a probability of between 80% and 90%, where the costs of primary heat exchanger, particles and lifts have largest contribution to the variance of the LCOE.

SP2.2.17The leaning tower of pasta: lessons in team performance and creativity from a core surgical training boot camp design challenge

Aims Unity of effort is an important component of strategic leadership and management theory associated with Core Surgical Training (CST) outcome. The aim was to determine the impact of team diversity on task completion: a creative design challenge, during CST Boot camp. Methods Attendees (n = 44) at a single Statutory Education Body’s CST Boot camp were stratified into teams related to specialty theme, and set a design challenge as described by Peter Skillman, to build the tallest free-standing tower out of spaghetti (20 pieces), tape (1 m), and string (1 m), with a marshmallow on top in 18 minutes. Primary outcome measure was tower height. Results Five teams (50%) completed the task with the tallest tower measuring 70cm (median 51, range 0-70). Median satisfaction with the simulation exercise was 4 (2-5) on a scale of zero to five, with five corresponding with highest satisfaction. Successful task completion was associated with team surgical specialty (p = 0.032), ethnicity ratio (p = 0.010,), and gender ratio (p = 0.003), respectively. On multivariable analysis, only team gender ratio was independently associated with tower height (HR 0.515, 95% CI 0.350 - 0.759, p = 0.001). Conclusion Modern leadership theory emphasises the important dynamic relationship between individual team members, the team, and task completion. General surgery themed teams with a gender mix were most successful in completing the design challenge; whether relative simulation performance predicts strategic organisational skill and career progression will be the next question.

Tower Height Raising and Embedding

‘Tower Height Raising and Embedding’ shows how to raise the height of towers, as well as how to detect embedded towers within a given tower. Raising the number of storeys of a capped tower by one is a construction similar in spirit to grope height raising, but more sophisticated. The new aspect, which receives careful treatment, is the geometric control needed to make the top storey arbitrarily small. An n-storey capped tower contains a capped tower with (n + 1) storeys and the same attaching region, and this can be realized by an embedding that places connected components of the top storey into balls of arbitrarily chosen small diameter. Consequently, endpoint compactifications of infinite towers may be embedded as well.

Sensitivity Analysis of the Levelized Cost of Electricity for a Particle-Based CSP System

This study presents a sensitivity analysis of the LCOE for a particle-based system with the costs of the most current components. New models for the primary heat exchanger, thermal energy storage and tower are presented and used to establish lower and upper bounds for these three components. The rest of component costs such as particle cost, cavity cost, lift cost and balance of power are set to lower and upper bounds estimating a 25% of uncertainty. Some relevant parameters such as lift efficiency and storage thermal resistance are also included in the analysis with a 25% uncertainty. This study also includes an upgrade to the receiver model by including the wind effect in the efficiency, which was not included in previous publications. A parametric analysis shows the optimum values of solar multiple, storage hours, tower height and concentration ratio, and a probabilistic analysis provides a cumulative distribution function for a range of LCOE values. The results show that the LCOE could be below $0.06/kWh with a probability of 90%, where the highest uncertainty is on the primary heat exchanger cost.

Measuring and predicting variation in the interestingness of physical structures

Curiosity drives much of human behavior, but its open-ended nature makes it hard to study in the laboratory. Moreover, computational theories of curiosity – models of how intrinsic motivation promotes complex behaviors – have been challenging to test because of technical limits. To circumvent this problem, we develop a new way to assess intrinsic motivation for building: we assume people build what they find interesting, so we asked them to rate the “interestingness” of visual stimuli – in this case, simple block towers. Adults gave a range of ratings to towers built by children, with taller towers rated higher. To probe interestingness further, we developed controlled tower stimuli in a simulated 3D environment. While tower height predicted much of the variation in ratings, people also favored more precarious towers, as inferred from geometric features and simulated dynamics. These ratings and features therefore give a clear target for computational accounts of curiosity to explain.

Analisis Matematika Pada Pembuatan Rumah Panggung Toraja

Geometri merupakan cabang ilmu yang mempelajari tentang hubungan antara titik-titik, garis-garis, dan bidang-bidang serta bangun datar dan bangun ruang. Dalam penerapan matematika geometri sangat membantu dalam kehidupan sehari-hari. Sebagai contoh penentuan tinggi menara dengan menggunakan bantuan cahaya matahari dimana dalam penentuannya bisa menggunakan sistem perbandingan. Kemudian menentukan jarak atau lebar sungai tanpa mengukur secara manual yaitu dengan menggunakan titik bantuan dan garis yang sebangun. Penelitian ini bertujuan mengetahui bagaimana hasil penerapan matematika dalam pembuatan rumah panggung Toraja. Dalam proses analisis dilakukan observasi dan wawancara serta dokumentasi untuk melihat proses pembuatan rumah panggung Toraja. Berdasarkan hasil analisis data yang diperoleh, ditemukan pola barisan pada tiang atau balok di setiap tipe rumah. Kemudian metode penggunaan garis sejajar, perpanjangan garis dan kesebangunan pada atap rumah. aplikasi matematika dapat diterapkan pada rumah panggung Toraja menggunakan persamaan dan fungsi parabola pada penentuan lengkungan atap rumah.Kata kunci: Geometri, Rumah panggung Toraja, Analisis, Persamaan Abstract. Geometry is branch of science that learning about the relationship between points, lines, sides , plane figure and solid figure. The application of geometry mathematics is very helpful in daily life. For example, the determination of tower height by using sunlight where in its determination can use the comparison system. Then, determine the distance or width of the river without measuring it manually, that is by using the help points and lines that are congruent. The aim of this research is finding out how the results of the application of mathematics in building Toraja Traditional house. The analysis process is done by observation, interview and documentation to see the process of building Toraja Traditional house. Based on the results of data analysis that is obtained, it was find the sequences pattern on the poles or beams in each type of house. Then the method of using parallel lines, lines extension and similarity on the roof of the house. Mathematics application can be applied in Toraja Traditional house by using parabolic equations and parabolic functions in determining the curvature of house roof.Keyword: Geometry,Toraja Traditional House, Analysis, Equation

Lattice and Tubular Steel Wind Turbine Towers. Comparative Structural Investigation

Renewable energy is expected to experience epic growth in the coming decade, which is reflected in the record new installations since 2010. Wind energy, in particular, has proved its leading role among sustainable energy production means, by the accelerating rise in total installed capacity and by its consistently increasing trend. Taking a closer look at the history of wind power development, it is obvious that it has always been a matter of engineering taller turbines with longer blades. An increase in the tower height means an increase in the material used, thereby, impacting the initial construction cost and the total energy consumed. In the present study, a numerical investigation is carried out in order to actively compare conventional cylindrical shell towers with lattice towers in terms of material use, robustness and environmental impact. Lattice structures are proved to be equivalently competitive to conventional cylindrical solutions since they can be designed to be robust enough while being a much lighter tower in terms of material use. With detailed design, lattice wind turbine towers can constitute the new generation of wind turbine towers.

The hidden value of large-rotor, tall-tower wind turbines in the United States

The significant upscaling of wind turbine size (nameplate capacity, rotor diameter, and tower height) has, to date, been driven primarily by a goal of minimizing the levelized cost of energy. But with wind’s levelized cost of energy now comparable with that of other generating resources, other design considerations besides cost-minimization have grown in importance—particularly as wind’s increasing market penetration begins to impose challenges on the electric grid. We find that taller towers and larger rotors (relative to nameplate capacity) can enhance the value of wind energy to the electricity system and provide other “hidden” benefits. Specifically, in regions where wind penetration has reached around 20%, we find a boost in wholesale market value of US$2–US$3/MWh. This is augmented by transmission, balancing, and financing benefits that sum to roughly US$2/MWh. The aggregate potential value enhancement of US$4–US$5/MWh is comparable with a 10%–15% reduction in levelized costs.