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"Alternative energy, nowadays, becomes more necessary than fossil fuels which might be destructing and polluting the earth’s environment. Wind can be one of the most cheap, secure, environment friendly and reliable energy supplies. Building Integrated Wind Turbine (BIWT) is becoming increasingly common as a green building icon and new method of assessing optimal building energy. However, to employ BIWT, it is important to design the building shape and swept area carefully to increase wind velocity. Some of numerous design forms of BIWT will be explained in this paper using CFD (Computational Fluid Dynamics) analysis to find the most effective BIWT design in urban area. This paper will focus on the maximum wind velocity which passes the swept area to get maximum wind power. The result shows that, building energy can be optimized through aerodynamic building design to get the maximum wind power for building energy consumption."

"Promoting the development of renewable energy is one of the important strategies for China to achieve energy conservation, emission reduction and energy transition. Although China has successfully developed a large-scale wind power industry, the serious problem of wind energy curtailment has led to the conflicts between decentralization and centralization. Based on this issue, the research questions of this paper are: Under China’s authoritarian regime, why does the Chinese government’s wind power governance mechanism cause the problem of wind energy curtailment to rise and fall periodically? Why does the governance mechanism show an unstable phenomenon of alternating between decentralization and centralization? Based on the authors’ interviews (including face to face interviews and remote interviews) targeting at seven provinces (cities/autonomous areas) in China from July 2014 to June 2022, this research proposes an analytical framework to explain the central and local government’s response strategies and governance cycles, and explores the background behind the local government’s response strategies- the “local routines”action mode. This research finds that when Chinese wind power governance mechanism faces the problem of wind energy curtailment, even if the central government proposes policy indicators and documents, the ultimate goal of local governments’ “local routines” is to maximize their own interests, instead of solving problems effectively. Under the situation that the central and local governments continue to make moves with each other, the problem of wind power curtailment has been characterized by huge fluctuations for a long time, which impacts the effect of energy conservation and emission reduction. This study contributes to a renewed understanding of central-local relations and environmental politics in Chinese authoritarian regimes, as well as to explain the puzzling alternating trajectories in the field of governance."

"In this research, an optimization and improvement of gas spring design is discussed. The gas spring is used as a suspension component of an energy storing prosthetic knee. The gas spring replaces the quadricep muscles of transfemoral amputee. A deterministic and a stochastic optimization is proposed in this research. Both models are used to determine the optimal design variables of the gas spring: cylinder diameter, cylinder length, extension stroke, and compression stroke. The optimal design variables resulted from the deterministic optimization model must be further analyzed to determine the effect of its variation to the objective function. Monte Carlo simulation is used to determine the effect of such variation and making improvement when necessary. Process capability index (Cp) is used as a criteria to make such improvement considering the contribution to variation of design variables to the objective function. Stochastic optimization is proposed to find the optimal design variables by taking into consideration the randomness of its parameters. The objective function of the stochastic optimization is to maximize the capability process. Both Monte Carlo simulation and stochastic optimization was solved using Oracle Crystal Ball Software. From the simulation, the reduction of compression stroke and extension stroke standard deviations resulted in 30% improvement of energy storage standard deviation. The Cp is also improved about 70% from 0.99 to 1.44. The stochastic optimization resulted in extension stroke and compression stroke which are shorter than deterministic optimization with 1.25 process capabilty."

"The book presents novel Computational Fluid Dynamics (CFD) techniques to compute offshore wind and tidal applications. The papers in this volume are based on a mini-symposium held at ECCOMAS 2018. Computational fluid dynamics (CFD) techniques are regarded as the main design tool to explore the new engineering challenges presented by offshore wind and tidal turbines for energy generation.The difficulty and costs of undertaking experimental tests in offshore environments have increased the interest in CFD which is used to design appropriate turbines and blades, understand fluid flow physical phenomena associated with offshore environments, predict power production or characterise offshore environments amongst other topics."

"Penelitian ini bertujuan untuk mengetahui faktor-faktor yang berhubungan dengan produktivitas kerja pada kalangan pekerja di PT X dengan menggunakan disain penelitian cross sectional. Jumlah sampel dalam penelitian ini adalah 136 pekerja yang didapatkan dengan metode simple random sampling. Pengumpulan data dilakukan dengan cara pengisian kuesioner mandiri dan wawancara 24 hours food recall. Analisis data yang digunakan dalam penelitian ini adalah analisis univariat dan bivariat dengan menggunakan uji Chi Square. Hasil analisis univariat menunjukkan bahwa 27,2 % responden masuk ke dalam kategori produktivitas rendah. Hasil analisis bivariat menunjukkan bahwa terdapat hubungan yang bermakna antara asupan energi (p-value 0,014) dan asupan zat besi (p-value 0,024) dengan produktivitas kerja.

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This cross sectional research aimed to identify factors associated with work productivity. The selection of 136 subjects was performed by simple random sampling method. Data collection is done by self-administered questionnaire and 24 hours food recall interview. Data analysis used in this research is univariate analysis and bivariate analysis using Chi Square test. Total of 27,2 % subjects were classified as low work productivity. There were correlations between energy consumption (p-value 0,014) and iron consumption (p-value 0,024) with work productivity."