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There are many interests in developing life-like robots, or robots which are both intelligent and autonomous. And, one obvious characteristics of life-like creatures is that they can autonomously develop and learn during their life span. Such abilities obviously depend on the ways of designing human-like minds. Then, a fundamental question is how to devise the innate, or built-in, principles behind the blueprint of a human-like mind, and to apply these findings to guide the design of the mind of life-like robots. In the literature, there are two schools of thoughts. One advocates the study of the nervous systems of biological brains (e.g. human brain) until the discovery of the blueprint of a mind. The second approach is to follow the path of invention and validation until the full understanding of physical principles which enable the design of an artificial mind that is as good as a biological mind. This paper embraces the second approach, and aims at formulating a new ground which could guide the design of the minds of life-like robots at various stages. In particular, the discussion is focused on answering the question of what life is from an engineering point of view. And, we approach the answer by examining the key steps of evolution from non-life to life. In this paper, five key steps of evolution from non-life to life will be discussed in detail. They are embodiment of energy flow, embodiment of signal flow, embodiment of knowledge flow, embodiment of decision flow, and embodiment of awareness flow. These findings are grounded on our engineering works toward the development of low-cost humanoid (LOCH) robot, and offer a unique perspective and an engineering basis. Whenever possible, the discussions in this paper are supported by real results of experiments on real robots.

This paper proposes an energy control method for dynamic obstacle crossing by a planar biped. This approach was tested in a simulation where it was found to enable the biped robot to cross obstacles of different heights, due to inertial forces, by leaning with the front foot on the obstacles. The propulsion energy of the system is produced by the rear leg, which is endowed with four actuated degrees-of-freedom (hip, knee, ankle, toes), and is controlled by force control with four degrees-of-freedom in the non-singular case, and three degrees-of-freedom in the singular case. This paper identifies ten geometric, energetic and servo-control parameters necessary for dynamic obstacle crossing. The methodology presented allowed the dynamic crossing of an obstacle up to 20 cm high, at which point the joint torque limit for the propelling ankle was reached.

A framework for creating thermal zones in a building for effective and efficient heating ventilation and air conditioning (HVAC) system design is introduced here. This method is based on simple “sort and eliminate” schemes and requires design cooling loads of conditioned spaces obtained from load calculation tools as primary input. The developed methodology is applied for creating thermal zones, determining corresponding supply conditions and ascertaining sizing of a dedicated outdoor air system (DOAS) with local recirculating units. A simulation study on a prototype-building model shows that a DOAS coupled with zoned recirculating systems that serve distinct thermal zones in a building (zoned model) perform comparatively better in controlling both space temperatures and humidity without significantly compromising HVAC energy and chiller loads than un-zoned HVAC systems serving the whole building as a single thermal block (un-zoned model). The consistency in the performance of zoned HVAC systems is verified by applying three different simulation weather files for New Delhi. Better performance along with logical and computational simplicity makes this design procedure a good alternative to traditional methodologies.

Although wrap-around heat pipes (WAHP) are widely used for enhanced dehumidification systems in tropical and hot-humid climates, very few literature resources have actually reported any control methodology applicable for WAHP dehumidifier systems for an entire year’s operation. In the present work, a methodology is proposed for an outdoor air unit equipped with a WAHP-based dehumidifier along with other auxiliary components. For this, the ambient conditions over an entire year are categorized into six constituent regions based on temperature and humidity levels. The proposed method involves defining specific control sequences corresponding to ambient conditions under each psychrometric region for tandem operation of system components. Fundamentally, this establishes a sort of segregated climatic control protocol for maintaining acceptable levels of humidity and temperature inside the conditioned spaces during a whole year’s operations. An energy simulation study is performed for two DOE prototype office buildings with six representative weather locations ranging from extremely hot and humid to dry and hot as per ASHRAE’s climate classification. Results show that a 100% outdoor unit comprising WAHP-based dehumidifier system equipped with proposed climatic controls saves cooling plant energy in a range of 1.5–19%, when compared with a similar WAHP-based outdoor unit without any climatic controls and auxiliary components. The proposed controls also enable the outdoor air unit in maintaining comparatively better indoor environmental conditions (temperature and relative humidity), resulting in lesser number of building occupied hours drifting away from prescribed indoor temperature and relative humidity limits than its basic counterpart without any climatic controls. This substantiates the intent and applicability of proposed control methodology for WAHP-based dehumidifier systems.

In this study, energy and exergy analysis was used to evaluate the performance of a vapor compression refrigeration system with a flooded evaporator and the causes of high temperatures of beverage during the production process determined. Subsequently, the components of the operation that require modification were identified in order to improve the system performance. The actual operating parameters related to energy and exergy analysis of the investigated beverage manufacturing plant were measured, the thermal properties of the beverage were determined from a calorimeter experiment, and mathematical models were developed based on the first and second laws of thermodynamics from the literature. The system energy and exergy efficiencies were 57.46% and 21.17%, respectively, whereas the system exergy destruction was 695.71kW. The highest exergy destruction among the components of the refrigeration system occurred at the cooling plate, followed by the ammonia compressor. The cooling plate also experienced a loss in the refrigerating effect of 43.59kW. Therefore, the cooling plate is the area with the highest potential for improvement. The ammonia compressor presents another potential area of improvement, which includes operating the compressor at a high compression ratio and high superheated temperature. However, the reduction of beverage inlet mass flow rate at the cooling plate offers the best opportunity to achieve a low beverage temperature between 1.00^∘C and 2.00^∘C and decreasing the system exergy destruction without incurring additional investment costs.

This paper presents the analysis of a modified vapor compression cooling system which uses an ejector as an expansion device. Expanding refrigerant in an ejector enhances the refrigeration effect and reduces compressor work. Therefore, it yields a better coefficient of performance. Thermodynamic analysis of a constant area ejector model has been done to obtain primary dimensions of the ejector for given condenser and evaporator temperature and cooling capacity. The proposed model has been used to design the ejector for three refrigerants; R134a, R152a and R1234yf. The refrigerant flow rate and the diameters at various sections of the ejector have been obtained by doing numerical modeling in Engineering Equation Solver (EES). Refrigerant R1234yf demanded the highest diameter requirements at a fixed 5^∘C evaporator temperature and 40^∘C condenser temperature for a given range of cooling load. Both primary and secondary refrigerants flow rates are higher for R1234yf followed by R134a and then R152a.

Senegal is located in West Africa with a population close to 16 million inhabitants unequally distributed on a land of 196,722 km² area. In the 2000s, a national energy information system (known as SIE-Sénégal) aiming at monitoring and forecasting the energy demand and the efficient planning of the energy infrastructure was put in place in the Ministry of Oil and Energies. A lot of data were recorded of which some are analyzed and presented here for a better understanding of the energy system of Senegal. In the period 2000–2013, the energy demand has been increasing reaching 3.72 Mtoe in 2013. The demand is covered by imported fossil fuels and traditional biomass. The energy consumption has been increasing in the same period from 1.69 Mtoe in 2000 up to 2.56 Mtoe in 2013. The energy pattern shows a lion’s share for the residential sector followed by the transport and industrial sectors. In the residential sector, firewood is the main fuel, and electricity is deemed marginal. The transport sector is dominated by the road subsector where diesel oil represents 81% of the energy use. In the industrial sector, more than 80% of energy used is from fossil origin and the share of coal is becoming significant.

Sustainable development goals (SDGs) acknowledge the interlinkages between human well-being, economic prosperity, and a healthy environment, and hence, are associated with a wide range of topical issues that include the securities of water, energy, and food (WEF) resources, poverty eradication, economic development, climate change, health, among others. As SDGs are assessed through targets to be achieved by 2030 and monitored through measurable indicators, nexus planning was applied as a transformative approach to monitor and assess progress toward SDG in 2015 and 2018 using South Africa. WEF nexus-related SDGs that were evaluated include Goals 2 (zero hunger), 6 (clean water and sanitation), and 7 (affordable and clean energy). The Analytic Hierarchy Process (AHP) was used to integrate indicators for each of the reference years. Resource management and implementation of WEF-related SDGs improved by 31% (from 0.155 to 0.203) between 2015 and 2018 in South Africa but remained marginally sustainable. The assessment provided an evidence-based support framework for improved and effective management strategies to meet set SDG targets. The connections between the WEF nexus and SDGs strengthen cross-sectoral collaboration among stakeholders, unpack measures for cooperative governance and management, and supporting outcomes that arise from different cross-sectoral interventions. As food production, water provision, and energy accessibility are the major socio-economic and environmental issues currently attracting global attention, the method enhances climate change adaptation.

This paper applies the energy limit concept to the stability problem of structures and structural systems. New concepts such as, the energy capacity that measures accumulated energy in the structure before failure and virtual large displacements that lead to significant plastic deformations are introduced and defined. Proposed theory considers full load cycle, from the initiation of the instability until complete collapse of the structure. New equations for the determination of critical loads are derived, presented, and compared to known results. Proposed new equations take into consideration simultaneous effects of axial, bending, shear and torque deformations. The results of the study are substantiated by comparison with examples with known answers.

The penetration of a plate under a high-velocity impact loading exhibits a very complex dynamic response process with highly nonlinear characteristics. A failure criterion was presented for the cracking model of homogeneous isotropic material. Based on this failure criterion, numerical simulation was conducted on the process of homogeneous isotropic metal plate impacted by a rigid ball at high-velocity by using LS-DYNA program. The relationship between effective stress and time at the impact point was expressed and analyzed. The curves of energy versus time were also plot to illustrate the impact process obviously.