关于节约使用造船生产动能源的探讨

降本增效是造船行业在激烈的市场竞争中取胜的最重要法宝，而降低造船生产动能源消耗，则是降本增效的重要一环，本文就我造船事业部在完成公司下达的各项生产经营活动中，如何加强对生产用动能源的管理进行探索，以期达到降低造船生产动能源费用的目的。

A sink moving scheme based on local residual energy of nodes in wireless sensor networks

In the application of periodic data-gathering in sensor networks,sensor nodes located near the sink have to forward the data received from all other nodes to the sink,which depletes their energy very quickly.A moving scheme for the sink based on local residual energy was proposed.In the scheme,the sink periodically moves to a new location with the highest stay-value defined by the average residual energy and the number of neighbors.The scheme can balance energy consumption and prevent nodes around sink from draining their energy very quickly in the networks.The simulation results show that the scheme can prolong the network lifetime by 26%-65%compared with the earlier schemes where the sink is static or moves randomly.

Evaluating performance of cutting machines during sawing dimension stones

The performance of cutting machines in terms of energy consumption and vibration directly affects the production costs. In this work, our aim was to evaluate the performance of cutting machines using hybrid intelligent models. For this purpose, a systematic experimental work was performed. A database of the carbonate and granite rocks was established, in which the physical and mechanical properties of these rocks (i.e., UCS, elastic modulus, Mohs hardness, and Schmiazek abrasivity factor) and the operational parameters (i.e., depth of cut and feed rate) were considered as the input parameters. The predictive models were developed incorporating a combination of the multi-layered perceptron artificial neural networks and genetic algorithm (GANN-BP) and the support vector regression method and Cuckoo optimization algorithm (COA-SVR). The results obtained indicated that the performance of the developed GANN-BP and COA-SVR models was close to each other and that these models had good agreements with the measured values. These results also showed that these proposed models were suitable tools in evaluating the performance of cutting machines.

Energy-Efficient Transmission Scheme for Mobile Data Gathering in Wireless Sensor Networks

Energy conservation in Wireless Sensor Networks (WSNs) has always been a crucial issue and has received increased attention in the recent years. A transmission scheme for energy-constrained WSNs is proposed in this paper. The scheme, called MIHOP (MIMO and Multi-hop), combines cluster-based virtual MIMO and multi-hop technologies. The multihop mode is employed in transmitting data when the related sensors are located within a specific number of hops from the sink, and the virtual MIMO mode is used in transmitting data from the remaining sensor nodes. We compare the energy consumption of different transmission schemes and propose an algorithm for determining the optimal hop count in MIHOP. A controllable mobile sink that reduces the energy consumed in sensor transmission is also adopted for data collection. The theoretical analysis and the Monte Carlo simulation demonstrate that the proposed scheme significantly outperforms individual virtual MIMO, multi-hop technologies, and double-string networks in terms of energy conservation. The energy consumption levels under the MIHOP scheme are approximately 12.98%, 47.55% and 48.30% less than that under virtual MIMO schemes, multi-hop networks and doublestring networks, respectively.

Athens in Crisis, Sustainable Mobility and Climate Change

Athens, a metropolis characterized by agglutination and compactness, but at the same time facing numerous urban and transport issues, saw its population swell during the 20th century which led to extensive urbanization phenomena. This continued urbanization increases profoundly all urban activities with transportation being the key driver in energy consumption. Theories for sustainable cities prerequisite are the integration of a number of acts in order to reduce energy consumption, with mobility being the first consideration among others. The aim of this paper is to critically explore implemented policies and plans as well as forthcoming strategic plans in terms of sustainable mobility as imposed in large scale regeneration plans in contemporary Athens. Research focuses on strategic interventions since the 1980s, such as the Athenian Daktylios （ring road for circulation management） and its later adjustments, the upcoming pedestrianization and unification of the commercial triangle and its subsequent tram line extension as well as the notable implementation of the metropolitan cycling network. Moreover, the discussion takes into consideration the implications of the Greek economic crisis in mobility choices, as aimless travels have been reduced to a minimum, several cars have been abandoned and cyclists seem to tentatively claim some space in the urban environment. What will likely be the next day in the Athenian historic centre？ Considering the transformations that are expected in the immediate future, this research paper explores their potential to enhance urban environment, reduce climate change impacts and amplify resilience.

Embedded Microcontrollers in Energy Conservation System

Energy conservation in homes has become important due to rising energy costs, increasing energy consumption, and a world-wide shift in concerns. This paper discusses an embedded home automation system that provides a method for monitoring and controlling household energy consuming devices. The hardware, software and system interface means utilized for implementation are presented and the particulars of the initial prototype are detailed.

Passive Cooling Strategies in Greening Existing Residential Building in Hot Dry Climate： Case Study in Bahrain

This paper will present several passive-cooling technologies and design features that can be adopted to reduce building heat gain without the need of excess energy consumption. A typical residential unit will be selected as case study and a three basic passive cooling strategies were selected to enhance the building envelop, as well as using appropriate shading devices and green roofing system that prove to be a good environment quality improver. IES energy simulation software will be used to evaluate the performance of the building. The study revealed a number of significant findings in reducing the energy consumption and enhancing the tenants＇ thermal comfort. American Society of Heating Refrigerating and Airconditioning Engineer （ASHRAE） standards specially via improving the performance of building envelop because it is the interface between internal and external environment. Moreover, improving the building envelope has recorded that overall energy and chiller energy consumption can be reduced up to 10.8% and 21.6% respectively, Therefore, it is anticipated that further reductions can be achieved via applying more passive cooling strategies. Finally, it could argue that the results of this paper will not only be applicable to Bahrain but also many countries that have similar climatic and environmental context.

Measurement and Simulation of Energy Consumption of Feed Drive Systems

In this study, in order to investigate the power consumption of feed drive system, mathematical models for the single-axis experimental apparatus are developed. This apparatus can be driven by either of ball screw or linear motor and it is possible to change the mechanical properties of such as grease viscosity of the table. Then, the power consumption is simulated by proposed method based on the mathematical model of feed drive systems and the simulated results are compared with the measured results of the experimental apparatus to confirm the validity of the proposed method. In addition, it is clarified that the energy usages of the feed drive system. The energy losses of the feed drive system are divided into the loss of each part and these energy losses are calculated by the proposed method. Then, it is investigated that the influence of the velocity and friction to the energy consumption of feed drive system. As the results, it is confirmed that proposed method can accurately predict the power consumption of the ball-screw feed drive system. It is also clarified that the energy usage for both of ball-screw and linear motor drive systems.