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The need for low power consumption in highly integrated systems-on-chip (SoCs), such as IoT-based smoke detection systems, has made frequent power-ups and power-downs a common practice. Although the device performance degradation caused by such frequent power-ups and power-downs is ignored in most circuit studies, in high-precision bandgap voltage references, the degradation of particular devices can result in a reference voltage shift. This work investigates the effects of frequent power-ups and power-downs on a simple bandgap reference circuit and demonstrates that the effects are real and non-negligible. Aging simulations based on simple bandgap reference circuits are performed to analyze the causes of device performance degradation and circuit output voltage shifts. The simulation results show that frequent power-ups and power-downs induce the negative bias temperature instability (NBTI) effect, a phenomenon that causes performance degradation in devices, such as threshold voltage degradation, under negative bias and high temperature conditions. Further, gate voltage waveforms of these devices were extracted for aging tests and the results of the tests in 14 nm FinFET and the NBTI aging model were used to infer the threshold voltage shift after 10 years at 125 °C. A circuit modification is proposed to mitigate the degradation of device performance and reference voltage shift. This work indicates that NBTI stresses introduced by frequent power-ups and power-downs need to be considered in circuit design. [ABSTRACT FROM AUTHOR]

PLLs with small areas, low power consumption, and low jitter are crucial for mobile applications. Hence, achieving a balance between the area, power consumption, and noise of a PLL is a significant issue. In this work, a compact, low-power, and low-jitter fractional-N PLL using Ring-VCO is introduced. In order to reduce area and power consumption, a single-ended Ring-VCO is implemented. Additionally, novel resistance matrixes are proposed to decrease phase noise. The resistor matrix creates 13 frequency tuning curves with close VCO gain and different initial frequencies, reducing the VCO gain and thus the overall noise while maintaining high tuning linearity. The proposed PLL is fabricated based on 12 nm FinFET technology with a 0.078 mm2 area. It achieves a 2.702 ps RMS jitter at 5.76 GHz while consuming 6.4 mW. Moreover, it maintains a low power consumption and a low RMS jitter across the entire frequency range. [ABSTRACT FROM AUTHOR]

The local legislation of ecological civilization construction is an important way to ensure the implementation of the ecologi -cal civilization clause of the constitution. When the local subjects with legislative power carry out legislation on ecological civilization construction, what normative basis should be followed in the constitution and how to implement the ecological civilization clauses of the constitution lead to the necessity of constructing the local legislative system for ecological civilization. Based on this, this article adopts the legal method of legal norm analysis to clarify the normative implications of the government' s ecological civilization construction responsibilities in the constitution from four aspects, including establishing the government' s ecological civilization responsibility objectives, clarifying the government' s specific ecological civilization construction and supervision responsibilities, developing the government ' s ecological civilization construction organizational procedures, and improving the institutional guarantee for the construction of ecological civilization. On this basis, this article extracts the logic of the constitutionality of the local legislation for ecological civilization construction, including clarifying the normative basis as the primary premise of constitutionality, following the constitutional norm as an important content of constitutionality, and defining the characteristic boundary and authorizing it according to the norm of constitutionality. The local legislation of ecological civilization construction is the embodiment of the higher law. Therefore, how to balance the tension between the unification of the central legal system and the flexibility of local governance in legislation is the key to the construction of local legislation in accordance with the constitution and the law for the construction of ecological civilization. As for the autonomous content of local legislation, ecological civilization construction legislation should maintain its characteristics. As for the subordinate content of local legislation, ecological civilization construction legislation should remain coherent. In terms of characteristic space, the characteristics of local legislation should be highlighted from two aspects: the pilot function of regulating the legislation for the construction of creative ecological civilization and the practical effect of strengthening the legislation for the implementation of eco -logical civilization construction according to local conditions. In terms of coherence requirements, the coherence of local legislation should be regulated from three aspects: the procedural legitimacy of legislative basis, the multi-dimensional guarantee of the institutional system, and the matching of powers and responsibilities of administrative obligations. In brief, the characteristic is the requirement of maintaining the two ' activenesses' of the locality, and coherence is the premise of ensuring the unity of a country' s legal system. Only in this way can it help to build a system of local legislation for ecological civilization construction. [ABSTRACT FROM AUTHOR]

A feasible constant work in process (CONWIP) policy can guide developer to better implement CONWIP system. The feasible policy should be selected from alternatives by evaluation. Therefore, how to generate more than one CONWIP alternative policy to evaluate is an inevitable problem in CONWIP practice. From the perspective of loop structure, we propose CONWIP design framework (CDF) which is a systematic design approach to obtain CONWIP alternative policies. The basic concepts and components for CDF are discussed in this paper. Based on CDF, we make 10 CONWIP alternative policies for hybrid flow shop in one-of-a-kind production environment, and these alternative policies are evaluated by simulation. The simulation result implies that (i) the CONWIP alternative policy with robustness has the potential to cope with more fluctuations in high-variety production environment; (ii) a better design for CONWIP policy will be able to enhance the system performance in practice; and (iii) the loop structure can serve as a parameter of CONWIP. [ABSTRACT FROM AUTHOR]

This paper studies the performance of constant work-in-process (CONWIP) assembly system with multi-loop in mass production, multi-products and low volume and one-of-a-kind production (OKP) environments using simulation. We propose five basic design patterns of CONWIP loop and develop eight control policies of CONWIP loop based on the design pattern for standard assembly system. The performance of developed loop policies is evaluated in three production environments. In particular, control policies of CONWIP loop in OKP environment provide a valuable reference for OKP shop floor controlling. A heuristic algorithm of searching work-in-process (WIP) upper bound, the deadlock phenomenon in CONWIP assembly system and suggestion are introduced specifically. The summary of CONWIP installation guidelines in the mixed assembly system can apply CONWIP theory to practise. [ABSTRACT FROM AUTHOR]

Pursuit of the shortest cycle time does not enhance benefits in one-of-a-kind production (OKP) environment. The quality of services is affected by the delivery on time for OKP enterprise, and a well-designed constant work in process (CONWIP) loop structure can effectively improve the performance of assembly system in OKP. The designed CONWIP loop structures have been tested by simulation under 2 assembly proportion conditions and 14 situations of fluctuation combinations, and analysed relationship between cycle time and punishment of tardiness. Simulation test shows that some of CONWIP policies have stronger robustness, which can perform well in several fluctuation situations. The authors propose an idea of dynamic configuration for CONWIP control. Furthermore, the design procedure of CONWIP can provide a reference and guidance for the application of CONWIP. This article extends the knowledge of OKP shop floor control and promotes implementation of CONWIP in pull manufacturing system. [ABSTRACT FROM AUTHOR]