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This study is aimed to conduct energy, exergy and economic analysis on a network of single-effect absorption chillers. First, the network was analyzed parametrically and then optimized to minimize exergy destruction and annual cost. Multi-objective optimization was performed by implementing a particle swarm optimization algorithm. The case study was conducted on the absorption chiller network in Iranian Marun Petrochemical Company. The results indicated the greatest effects of the solution heat exchanger efficiency and network inlet cooling water temperature on energy and exergy performance coefficients and annual cost. Accordingly, decreasing the network inlet cooling water temperature from 35 to 25 °C increased energy and exergy performance coefficients by 5.3 and 6.2%, respectively, and reduced annual cost by $70,000.00. Besides, increasing solution heat exchanger efficiency from 60 to 80% increased energy and exergy performance coefficients by 5.9 and 2.1%, respectively, and decreased the annual cost by $60,000.00. According to the optimization results, the economic function of the network saved 9.95%, so that if the network works in optimized thermodynamics and economic conditions, the cost decreases by 3.24% compared to the typical manner.

Software aging is a risk associated with the continuous operation of software, and it is essential and meaningful to develop anti-aging technology to offset or mitigate the aging phenomenon. While considerable attention has been devoted to software aging and anti-aging techniques, few studies have focused on single-event effect as a software-aging reason in the context of a space environment. In this study, aiming at the software-aging problem caused by the specific reason above, besides the classic software rejuvenation, we further explore the anti-aging effects and rules of software reliability design modes, including triple modular redundancy (TMR) and logical partitioning. Reliability and availability are used as aging indicators, and the anti-aging effect of reliability design modes and rejuvenation policy is quantitatively analyzed through probabilistic model checking. The simulation and theoretical results show that the reliability design mode can alleviate software aging. However, the TMR mode is time-sensitive. It is found that the application of the rejuvenation policy makes time-sensitivity disappear. A combination of reliability design modes and rejuvenation policy can obtain the best anti-aging effect. The analysis and discussion in this paper can provide useful insights for software researchers to instantiate different software anti-aging inventions or new applications.

A 3D model of the negative-channel metal-oxide semiconductor (NMOS) structure in a 65-nm complementary metal-oxide semiconductor (CMOS) inverter was built based on technology computer-aided design (TCAD) three-dimensional (3D) device simulation software. The single-event effect caused by a heavy ion at different incident positions was simulated and analyzed using the TCAD–HSPICE mixed-mode simulation. Then, an analytical model was established to describe the relationship between the incident position of the ion and the charge collected by the NMOS drain. Finally, an HSPICE simulation approach based on this model was developed and verified by simulations.

Absorption heat pump attracts increasing attention due to its advantages in low grade thermal energy utilization. It can be applied for waste heat reuse to save energy consumption, reduce environment pollution, and bring considerable economic benefit. In this paper, three important aspects for absorption heat pump for waste heat reuse are reviewed. In the first part, different absorption heat pump cycles are classified and introduced. Absorption heat pumps for heat amplification and absorption heat transformer for temperature upgrading are included. Both basic single effect cycles and advanced cycles for better performance are introduced. In the second part, different working pairs, including the water based working pairs, ammonia based working pairs, alcohol based working pairs, and halogenated hydrocarbon based working pairs, for absorption heat pump are classified based on the refrigerant. In the third part, the applications of the absorption heat pump and absorption heat transformer for waste heat reuse in different industries are introduced. Based on the reviews in the three aspects, essential summary and future perspective are presented at last.

In this work, optimum operating condition maps are generated covering wide ranges of refrigeration and sink temperatures for single- and double-effect LiBr–water vapour absorption refrigeration cycle. These optimum condition maps will be useful to choose optimum operating conditions while designing LiBr–water cycle for desired applications. Methodology for generating such maps is discussed in detail, which can also be used for other absorption refrigeration cycles with various working fluids. Three configurations of LiBr–water absorption refrigeration cycles, single effect, double-effect series flow and double-effect parallel flow, are analysed with the most accurate thermodynamic property correlation available in the literature. Sensitivity of cycle performance to various operating variables such as generator, absorber and condenser temperatures is determined. Second law analysis shows that when a higher temperature heat source is available, double-effect cycles are more effective over single effect as they have higher coefficient of performance.

This paper presents the performance of a single effect absorption cooling system under three different climates in Saudi Arabia. The considered system capacity is 10.5[Formula: see text]kW and uses LiBr/water pair. The study results indicated that considering the dynamic response of the cooling cycle significantly increases (close to 30%) the time taken to reach steady-state operations and that the sensitivity of the system to form precipitation of LiBr also increases. Also, the dynamic performance was investigated under different heat inputs and resulted in shorter transient period with increasing the heat input. In addition, the performance of the solar absorption system was investigated for a representative summer day in different climatic regions in Saudi Arabia. The results indicated the requirement of different areas of collectors to meet the absorber heating demand from 09:00 a.m. to 04:00 p.m. if there is no auxiliary heating. Auxiliary heating is required from 04:00 p.m. to 09:00 a.m. Finally, the results indicated that the system performs better in Riyadh city than in Dhahran and Jeddah. This study emphasizes the importance of taking into consideration the thermal inertia of the system components when analyzing the performance of such systems.

Due to the intrinsic lack of restoring paths, dynamic logic circuits have significant single-event susceptibility, and thus, they are not preferred in applications requiring high reliability when compared to static logic. However, in high speed applications, this circuit family is still very attractive. This papers presents two layout-based single-event resilient dynamic logic designs. The resultant SET pulse is suppressed because of charge-sharing in the layout-level. Simulation results verify that they enjoy higher single event tolerance. Experimental results validate the fact that approximately 20?~?30 % of magnitude reduction in cross-section is achieved in both designs. On the other hand, the increase in single-event performance is achieved at the expense of power and area overheads of 10 and 15 %, respectively, using our layout style in 130 nm CMOS bulk technology.

Simulating the coupling effect brought by freeze-thaw and carbonation environment, we experimentally investigated concrete durability, the variation characteristics of both concrete dynamic elastic modulus, and its neutralization depth. The influences imposed by carbonation on the freeze-thaw damage of concrete was studied as well and vise versa so as to shed light on the influencing mechanism together with the mutual interaction between them. The experimental results show that the damage caused by the coupling effect of freeze-thaw and carbonation on concrete is severer than any single effect of them two could bring. This provides certain theoretical references and paves down foundations for the further study in concrete durability related by the coupling environmental effect.

Using Technology Computer-Aided Design (TCAD) 3-D simulation, the single event effect (SEE) of 25 nm raised source-drain FinFET is studied. Based on the calibrated 3-D models by process simulation, it is found that the amount of charge collected increases linearly as the linear energy transfer (LET) increases for both n-type and p-type FinFET hits, but the single event transient (SET) pulse width is not linear with the incidence LET and the increasing rate will gradually reduce as the LET increases. The impacts of wafer thickness on the charge collection are also analyzed, and it is shown that a larger thickness can bring about stronger charge collection. Thus reducing the wafer thickness could mitigate the SET effect for Fin-FET technology.

The effect of p-well contact on the n-well potential modulation in a 90 nm bulk technology with P+ deep well is studied based on three-dimensional (3-D) TCAD device simulations. Simulation results illustrate that the p-well contact area has a great impact on the n-well potential modulation and the enhancement factor will level out as the p-well contact area increases, and that at the same time the increase of p-well doping concentration can also enhance the n-well potential modulation. However, the effect of p-well contact location on the n-well modulation is not obvious as the p-well contact distance increases. According to our simulation results, it is proposed that the p-well contact area should be cautiously designed to mitigate single event effect (SEE) in the P+ deep well technology.

In this study, the characteristics of the hybrid type absorption chiller, combined with the single effect absorption chiller and the double effect absorption chiller, are numerically studied to use waste hot water effectively. In the case of the full load for hybrid type absorption system, the concentration and temperature of LiBr solution increase about 2.2°C and 0.7%, respectively, at the single effect generator by the hot water. As the partial load decreases, the COP decreasing ratio of the hybrid type absorption chiller is higher than that of the double effect absorption chiller. On the other hand, COP f shows the opposite result of COP. The cycle COP of the hybrid type is about 1.07 on the full load which is 0.11 lower than that of the conventional double effect type. But COP f of the hybrid type is 1.28 which is 0.22 larger than that of double effect type. In the case of 50% partial load, COP f of the hybrid type is 2.66 and at below 50% partial load, system can be operated without any fuels. As the temperature of hot water and the mass flow ratio of hot water increase, the fuel saving ratio increases. The effect of the inlet temperature on the COP and COP f is much more significant than that of the mass flow rate of the hot water.

Some asynchronous circuit techniques are proposed to provide a new approach to Single Event Effect (SEE) tolerance in synchronous circuits. Two structures, Double Modular Redundancy (DMR) and Temporal Spatial Triple Modular Redundancy with Dual Clock Triggered Register (TSTMR-D), are presented. Three SEE tolerant 8051 cores with DMR, TSTMR-D and traditional Triple Modular Redundancy (TMR) are implemented in SMIC 0.35 μm process. The results of fault injection experiments indicate that DMR has a relatively low overhead on both area and latency than TMR, while tolerates SEU in sequential logic. TSTMR-D provides tolerance for both SEU and SET with reasonable area and latency overhead.

The effect of administering different quantities of a JHA topically and orally to the last instar larva ofSpodoptera litura of different ages has been studied. With both modes of treatment the effects comprised prolongation of the life of the instar followed frequently by death; imperfect ecdysis adversely affecting survival; production of non-viable larval-pupal intermediates, and occurrence of extra larval moults. Topical treatment is more effective but ecdysial failure and production of 1-p intermediates are more frequent with oral administration. A single supernumerary larval moult may be caused by administering a large quantity of JHA to 1 day old larva. Supernumerary instars are non-viable. Contrary to expectation, 1-p intermediates produced by early treatment show more pupal characters whereas middle-aged larvae show more larval characters. Prolongation of larval life caused by small quantities of JHA is the largest single effect which results into larval mortality.

Transient solutions are developed for the buildup of a concentration gradient in the single loop solute cycling model of the renal medulla. The “pump” from ascending limb to descending limb is considered in both unsaturated and completely saturated modes of operation. Both analytic solutions and semianalytic solutions obtained from inverting Laplace transforms are considered. The classic representation of concentration buildup by the multiplication process is compared with calculated profiles. The “single effect” is found to vary both in time and space.