As the problems of energy shortage and environmental pollution are increasingly escalating, the development of efficient and sustainable energy storage technologies has become extremely important. Among these technologies, supercapacitors are receiving significant attention due to their relatively high energy density and power density, making them a promising solution for future energy needs. The unique combination of fast charge-discharge capability, long cycle life, and reliability makes supercapacitors attractive in fields such as portable electronic devices, electric vehicles, and renewable energy integration. In particular, composite materials containing carbon nanotubes and metal oxides are of great research interest in improving the performance of supercapacitors. For example, incorporating non-precious metal oxides (such as manganese oxide and nickel oxide) or precious metal oxides (such as ruthenium oxide) into carbon-based materials can significantly enhance electrochemical performance. An appropriate loading quantity of active materials plays a crucial role in achieving high specific capacitance. Furthermore, different composite preparation techniques have a significant impact on the microstructure of the materials, thereby markedly changing the electrochemical characteristics of the electrode and affecting its overall performance in energy storage systems.

In many circuit systems, it is necessary to compare the amplitude of the signal, so it is necessary to design an absolute value comparator to compare the input values. This paper introduces a four-bit binary absolute value comparator, which can realize the size comparison of four-bit binary signed numbers. This paper introduces some basic working principles of the absolute value comparator through the truth table. The absolute value is obtained by using the adder to invert the input four-digit number and add 1. The three-bit comparator is realized by connecting the three comparators, and the four-bit absolute value circuit is connected with the three-bit comparator to realize the four-bit signed absolute value comparator. The final design results are displayed using the simulation software Multisim, and it can be observed that the circuit works in a normal way. Finally, this circuit is simple and easy to implement, and has good delay and energy consumption. In the future, it can be composed of existing components such as half adders and comparators, which can reduce the design cost and design difficulty to a certain extent.

Mosfets are the most important and basic part of integrated circuits, which the modern information network relies on. Combing a great number of mosfets, most integrated circuits would require the constituent part of themselves work in a stable and reliable state. Though, having been improved both in materials and constructures for tens of years, various types of mosfets still face the great danger of failure. This article would generally introduce this important issue of integrated circuit both on the issue and the methods of improvements, based on former researches, first making the classifications according to the formation mechanism of the failure modes, with an example of each failure mode, then introducing the train of thought of each kind of failure modes showed above. This article would be a summary on most common failure modes of cmos devices, with the formation mechanisms and their solutions, though not being comprehensive about most situations, it is supposed to be a reference on cmos circuit design, which may help to choose the specific devices and to improve the performance of the circuit in actual productions.

The development of the integrated circuit industry has led to an increase in both the operating frequency and integration density of CMOS circuits, which has also resulted in a rising power density. To address the various adverse effects of increased power consumption on chip design, low-power design has become an essential aspect of chip development. This paper begins by examining the origins of power consumption and, based on this analysis, introduces low-power design techniques at the system architecture level, RTL level, as well as clock gating, multi-threshold voltage technology, and power gating techniques. These approaches allow designers to choose the optimal combination of power-saving techniques according to specific design needs, achieving lower power consumption without compromising performance.

In recent years, with the surge in the number of vehicles, traffic congestion has become an increasingly severe global issue. So Intelligent Traffic Signal Control Systems have emerged as a critical component of transport systems to address this challenge by optimizing traffic flow, reducing delays, and enhancing road safety. The intelligent system depends on several advanced technologies, such as IoT devices, big data analytics, and artificial intelligence algorithms. Also, the system can dynamically adjust traffic signals based on real-time road conditions via technologies such as Vehicle-to-Infrastructure (V2I), Vehicle-to-Vehicle (V2V), and Vehicle-to-Everything (V2X) communication, which successfully improves traffic flow during peak hours, and minimizes congestion. The review will also mention successful case studies in cities such as Beijing, where smart systems have significantly improved traffic efficiency. The last part of review will focus on future developments about scalability, cost-effectiveness, and data security to ensure the continued success of these systems in modern urban environments.

Rapid urbanization in China has led to severe challenges in urban water resource management, including water scarcity, pollution, and the impacts of climate change. This study examines innovative technologies such as water recycling, rainwater harvesting, and urban green infrastructure, focusing on their implementation in major cities like Beijing, Shenzhen, and Guangzhou. Through case studies and data analysis, the research evaluates the effectiveness of these solutions in addressing the pressing water management issues. The findings suggest that integrated water management strategies, supported by strong policy frameworks and public involvement, are critical for achieving sustainable urban water systems. The study concludes with recommendations for improving urban resilience to water-related challenges in the face of ongoing climate and demographic pressures.

In the development of integrated circuits, operational amplifiers are indispensable basic units CMOS operational amplifiers are the core components in analog integrated circuits, which are widely used in signal acquisition, data processing, communications and other fields. components in analog integrated circuits, which are widely used in signal acquisition, data processing, communications and other fields, and their performance has a direct impact on the accuracy and stability of the entire system. With the continuous development of electronic technology, CMOS operational amplifiers play a vital role. operational amplifiers play a vital role in many fields. However, the misalignment problem has been one of the key factors affecting the performance of However, the misalignment problem has been one of the key factors affecting the performance of CMOS operational amplifiers. This paper introduces the basic principles of CMOS operational amplifiers, thoroughly studies the phenomenon of CMOS operational amplifiers' misalignment. This paper introduces the basic principles of CMOS operational amplifiers, thoroughly studies the phenomenon of CMOS operational amplifiers' misalignment, the definition and sources of the misalignment voltage and its effects, and analyzes the main reasons for its generation, including device mismatch, process deviation, and so on. In this paper, we summarize several methods to reduce distortion from dynamic distortion elimination technology and design and process optimization, which can effectively reduce the distortion voltage of CMOS op amps. The main dynamic misalignment elimination techniques are chopping and auto-zeroing, as well as a special form of auto-zeroing, i.e., correlation dual- sampling technique. Design and process optimization includes two methods of device selection and matching optimization and circuit topology design.

Since the 21st century, climate change is a global issue that affects every corner of the world and extreme weather occurs frequently. The Paris Agreement proposes that countries should strengthen their response to the threat of climate change. Countries around the world are actively seeking energy transition. Photovoltaic power generation and wind power generation are the most important renewable energy generation methods in the world. These two technologies are pollution-free and zero carbon emission during the power generation process. But from the perspective of the full life cycle, there is still some controversy over the environmental benefits of both at present. This article normalizes and analyzes the input-output data of the cradle to grave process using the LCA methodology, and the results indicate that the environmental impact of photovoltaic power generation throughout the full life cycle is significantly greater than that of wind power generation. Based on the above conclusions, several measures are proposed to improve the ecological benefits of both photovoltaic and wind power generation.

Hydrogen Energy is the chemical energy that results from the chemical reaction of hydrogen and oxygen. It is also an environmental-friendly, safe and clean energy which can provide sustainable resources. Nowadays, hydrogen energy has become more and more popular due to its advantages. Therefore, the technologies of hydrogen production, transport and storage are obviously significant. To begin with, according to prior research, this section examines the benefits and advantages of hydrogen energy for humanity, as well as its developmental trajectory. Furthermore, it highlights the essential technologies of the complementary multi-energy hydrogen production system, detailing methods capable of generating hydrogen. The passage involves different kinds of energy production technology that help produce hydrogen energy. Lastly, the transportation and storage technology of hydrogen energy is summarized, and the paragraph also generalizes its disadvantages and outstanding features. This passage provides references for the development of renewable energy complementary systems controlling hydrogen technology.

The potential applications of transparent, adaptable electronic devices in the human body are driving up demand for them. For flexible and wearable electronics, such as medical surveillance devices and artificial skin, pressure sensing is mandatory. The flexibility and sensitivity of pressure sensors have advanced recently owing to developments in material and device structure. Moreover, their low manufacturing costs enable widespread implementation, leading to promising application prospects. The sensors utilize different materials and structures, including capacitive pressure sensors with ionically charged CFMs, magnetic particle-infused carbon sponges, CNT-PDMS composites, and MoSe2/MWNT combinations. These sensors offer advantages such as high sensitivity, wide pressure-detecting ranges, optical transparency, and energy efficiency. They can detect both large and subtle human movements, from walking and finger bending to breathing and eye blinking. The fabrication methods range from simple and cost-effective processes to more complex techniques like photolithography. Many of the sensors incorporate carbon nanotubes (CNTs) in various forms, exploiting their excellent electrical properties. The review highlights the potential of these sensors for healthcare monitoring, clinical diagnosis, and integration into wearable electronics, emphasizing their flexibility, biocompatibility, and ability to provide real-time, non-invasive measurements of physiological signals. Moreover, their low manufacturing costs enable widespread implementation, leading to promising application prospects.