Serial System Research Articles

A Review of PCI Express Protocol-Based Systems in Response to 5G Application Demand

In the Personal Computer (PC) industry, systems with updated configurations, components, and new technologies are introduced to the market each year. Resource arrangement and the prediction of market requirements for products are common challenges in each development phase of these products. Technologies such as Artificial Intelligence (AI), the Internet of Things (IoT), and cloud services influence the PC industry, and product strategies must be examined to fit the requirements of the market. Common designs and market predictions can influence product line resource arrangements, and 5G applications are causing an increasing demand for 5G-enabled products in the market. However, PC systems based on PCI Express, NVMe, USB, and TPM have been introduced into the market with more secure solutions, and common designs and predictable market demand can provide more reliable strategies for navigating these issues. The research reported here is based on the serial bus system, which should simplify protocol transition between PCI Express, CXL, USB 4, and NVMe. Serial bus behavior should also influence performance and power consumption. Product strategies could be based on securing demand with power and performance in AI, the IoT, cloud storage, and high-performance computing. Based on performance and power requirements, application layer devices can use PCIe-based systems to provide secure solutions to extend 5G system reliability.

A software PAM4 clock data recovery algorithm for high‐speed serial communication

Time jitter analysis is an important means to evaluate the performance of a high-speed serial communication system. Clock data recovery (CDR) is a critical component of a high-speed serial link that recovers the reference clock from a signal for jitter analysis. Traditional studies focused on CDR technology for the non-return-to-zero pattern based on a hardware design, but little work has been devoted to the software CDR especially for the four-level pulse amplitude modulated (PAM4) encoded data signals. This study proposes a new software algorithm to recover clocks from PAM4 signals that is capable of extracting synchronous clocks from PAM4 signals to design an ideal software phase-locked loop for clock recovery. The proposed algorithm extracts more types of data transition edges than hardware methods to avoid the loss of jitter information. Besides, the algorithm designs an ideal phase-locked loop to improve the filtering accuracy. This algorithm has been implemented in MATLAB, and shows superior performance to that of conventional CDR technology.

Out-of-Plane Tensile Properties of Cross Laminated Timber (CLT)

A systematic investigation is still lacking for tension out-of-plane in cross laminated timber (CLT), as a planar timber construction product. The objectives of the present study are the determination of the tensile properties of CLT made of Norway spruce, the identification of essential product-specific influencing parameters and a comparative analysis with glulam. For this purpose, seven test series were defined, which allowed the determination of the tensile properties on board segments and thereof produced glulam and CLT specimens by varying the number of layers, layer orientation and number of elements within a layer. The orthogonal laminated structure of CLT led to between 50% and 70% higher tensile properties out-of-plane, which is explained by the different stress distribution compared to glulam; the regulation of 30% higher properties than for glulam is suggested. In addition, the lognormal distribution turned out to be a more representative distribution model for characterizing the tensile strength out-of-plane than the Weibull distribution. This was also confirmed with regard to the investigated serial and parallel system effects, in which a clearly more homogeneous behavior was found in CLT compared to glulam, which in turn can be attributed again to the different stress distributions.

Efficient 3D observation of steel microstructure using serial sectioning with precision cutting and on-site etching

This paper describes a fast and precise 3D observation method for steel microstructures using a cutting-based serial sectioning system with on-site etching. The method employs automated 3D internal structure microscopy for ferrous materials and on-site manual etching without detaching the specimen during the process. A notable feature of this system is that it uses precision cutting instead of polishing for surface fabrication, which has advantages in the fabrication speed, applicability in dry conditions, and controllability of the fabrication depth. The precision cutting of a dual-phase (DP) steel achieved a low roughness comparable to polishing. Furthermore, the on-site etching process by dropping etchant yielded sufficient contrast between ferrite and martensite phases. Observation of DP steel cross sections at 1 μm intervals afforded a 3D image in the range of 690 × 518 × 103 μm3 with a resolution of 0.144 × 0.144 × 1.0 μm3. The processing time was approximately five minutes for each cross section and almost half a day for the whole image, which was much more efficient than manual serial sectioning that requires a few weeks. The microstructures were also visible in reconstructed lateral cross sections of the 3D image, which proved the sufficient quality of our imaging. In addition, the segmented volume revealed the non-uniform martensite distribution among cross sections quantitatively. Most of them were connected in 3D, while they seemed to be separated in 2D. These results demonstrated the usefulness of our method with precision cutting and on-site etching.

Grand canonical partition function of a serial metallic island system

We present a calculation of the grand canonical partition function of a serial metallic island system by the imaginary-time path integral formalism. To this purpose, all electronic excitations in the lead and island electrodes are described using Grassmann numbers. The Coulomb charging energy of the system is represented in terms of phase fields conjugate to the island charges. By the large channel approximation, the tunneling action phase dependence can also be determined explicitly. Therefore, we represent the partition function as a path integral over phase fields with a path probability given in an analytically known effective action functional. Using the result, we also propose a calculation of the average electron number of the serial island system in terms of the expectation value of winding numbers. Finally, as an example, we describe the Coulomb blockade effect in the two-island system by the average electron number and propose a method to construct the quantum stability diagram.

A Power Allocation Strategy for DC Line Fault in Serial Hybrid LCC-MMC HVDC System

The serial hybrid line commutated converter-modular multilevel converter (LCC-MMC) high voltage direct current (HVDC) system has structural features that cause the inverter side three MMCs to form a closed-loop after a DC line fault. If the steady-state control strategy of the MMCs is still used during the phase shift, there will be a severe overcurrent problem. In addition, during the power recovery process, the rectifier side and the main converter MMC simultaneously deliver active power to the constant active power converter, resulting in the loss of control of the constant active power converter. Based on this, an MMC active power allocation strategy is designed in this paper. In this strategy, during DC line faults, the constant DC voltage converter is switched to constant active power control, and the other two converters are switched to voltage droop control. During the phase shift, the active powers of the two droop converters are allocated according to the droop coefficients, and the active powers of the MMCs are dynamically and smoothly reduced to solve the uncontrol problem of the two converters during the power recovery process. Finally, a serial hybrid LCC-MMC HVDC system model is built in PSCAD/ETMDC based on engineering design parameters to verify the accuracy and validity of the proposed control strategy. Comprehensive simulations show that the proposed strategy can reasonably allocate the powers of the MMCs in case of DC line fault. Besides, it still shows great adaptability with different power distribution, fault locations, and fault resistances.

Contracts design for serial delivery with connecting time spot: From a perspective of fourth party logistics

For a serial delivery system, the latter 3PL needs to be prepared at the transshipment node in advance to reduce the total delivery time. In this paper, we propose the concept of Connecting Time Spot (CTS) to help 4PL schedule the latter 3PL when to wait at the transshipment node. We study a serial delivery system with a 4PL and two 3PLs, where 4PL designs optimal contracts with two types of CTS (GCTS is derived by system parameter and DCTS is determined by 4PL’s optimization) to induce 3PLs to exert the optimal effort levels. We analyze the effects of CTS on the system profit in the centralized system. For the decentralized system, we particularly investigate the optimal contracts in three penalty modes which are according to the occupancy of the warehouses. The results show that CTS can avoid 3PLs’ idle resources and enhance the system profit for serial delivery both in the centralized system and the decentralized system. Compared with GCTS, DCTS has a better performance in enhancing the system profits. Also, the optimal incentive contracts achieve Pareto improvement for system profits. Interestingly, one 3PL’s delivery penalty mode will not affect the other 3PL’s optimal contracts.

Multi-echelon inventory optimization in closed-loop supply chain

In this paper, we are interested in the stock control in the closed-loop supply chain and its application to the cylinder packaged gas supply chains of Air Liquide company. Air Liquide is a multinational company producing and distributing industrial and medical gases. Firstly, we introduce a new classification of demand profile and perform a comprehensive study of the goodness of fit of demands sizes and time between successive demands based on real data. As well known in the literature (Boylan and Syntetos (2021)), we find that negative binomial distribution fits better demand sizes and intervals. Secondly, we explain how to use a single echelon model that is easy to implement on the field, to control inventory and compute the stock target in the observable part of the closed-loop supply chain. It is modeled as a multi-echelon serial inventory system. Finally, we perform numerical analysis and comparisons of methods to compute the stock target of the observable part of the closed-loop supply chain with real data. Those methods are derivated from the up-to-level periodic inventory review policy where we vary the statistical distribution of the demand and the measure of the service level. Using the Item Fill Rate (IFR) as a service level measure in the stock target calculation, reduce the stock target by more than 10% compared to the stock target obtained using the Cycle Service Level (CSL). We also investigate methods using compound Poisson distribution for demand models.

Electric Vehicle Control System by using Controller Area Network Communication

The Controller Area Network (CAN) communication protocol is designed by Bosch in the 1980s as a doubled wired, differential voltage-based serial communication system for control systems. Electric vehicles, like Gasoline vehicles, require controllers to regulate load operation, where conventional point-to-point communication system gets outcome of huge number of cables in the harness. CAN is used to minimize the amount of cables and enable various controllers to transfer data and accomplish complicated jobs simultaneously. This paper presents the design of a CAN-based control system to be used as a replacement for the existing system and shows the development of four modules as well as a proposed implementation for the complete system. Individual modules will be developed initially and later interfaced to the CAN network with CAN controller modules. All modules are connected with a twisted pair of cables for data transmission with CAN.

A Novel Metaheuristic Algorithm: The Team Competition and Cooperation Optimization Algorithm

Metaheuristic algorithm is a generalization of heuristic algorithm that can be applied to almost all optimization problems. For optimization problems, metaheuristic algorithm is one of the methods to find its optimal solution or approximate solution under limited conditions. Most of the existing metaheuristic algorithms are designed for serial systems. Meanwhile, existing algorithms still have a lot of room for improvement in convergence speed, robustness, and performance. To address these issues, this paper proposes an easily parallelizable metaheuristic optimization algorithm called team competition and cooperation optimization (TCCO) inspired by the process of human team cooperation and competition. The proposed algorithm attempts to mathematically model human team cooperation and competition to promote the optimization process and find an approximate solution as close as possible to the optimal solution under limited conditions. In order to evaluate the performance of the proposed algorithm, this paper compares the solution accuracy and convergence speed of the TCCO algorithm with the Grasshopper Optimization Algorithm (GOA), Seagull Optimization Algorithm (SOA), Whale Optimization Algorithm (WOA) and Sparrow Search Algorithm (SSA). Experiment results of 30 test functions commonly used in the optimization field indicate that, compared with these current advanced metaheuristic algorithms, TCCO has strong competitiveness in both solution accuracy and convergence speed.

The Lomax-Lindley distribution: properties and applications to lifetime data

This paper introduces a new three-parameter distribution which is obtained by combining the Lomax and Lindley distributions in a serial system and is called the Lomax-Lindley distribution. The new distribution is quite flexible to model lifetime data. This distribution provides a simple form for hazard rate function which can be increasing, decreasing, bathtub-shaped and unimodal for different choices of the parameter values. Some statistical properties of the Lomax-Lindley distribution such as quantiles, moments, order statistics, Renyi entropy and mean deviations are discussed. The maximum likelihood estimators of its unknown parameters are obtained and the approximate confidence intervals of the parameters are provided. A Monte Carlo simulation study is conducted to investigate the performance of the maximum likelihood estimators and their corresponding confidence intervals. Finally, two real data sets having bathtub-shaped and unimodal hazard rate functions are analyzed and it is shown that the proposed distribution can provide a better fit than other distributions for both lifetime data.

Causally-guided acoustic optimization of rigidly-backed micro-perforated partitions: Case studies and experiments

A causal-based optimization criterion has been theoretically derived in an earlier study for a single-layer micro-perforated absorber (MPA) under normal incidence. In this study, it is extended to multiple and parallel MPA systems as well as to general incidence. It is shown that the ultimate wideband performance of multiple (resp. parallel) MPAs scale on their overall (resp. effective) cavity depths, with adverse effect of the incidence angle. The multi-variate constrained optimization process requires maximising the sensitivity of the total reflected intensity, integrated over all wavelengths, with respect to the parameters constitutive of the micro-perforated panels. It leads to perfect absorption and broad bandwidth efficiency at one or several resonant states of the MPAs. As for serial MPA systems, it is a suitable sub-optimal alternative to total absorption and inverse-frequency weighted absorption maximizations. Concerning MPA arrays, the causal-based optimal design brings near-unit absorption over a wide bandwidth in the low-frequency domain due to efficient grouping and merging of cross-coupled resonant states. It brings similar performance to direct maximization of the total inverse-frequency weighted absorption that puts weight on the low frequencies. These optimal performances have been verified through standing wave tube absorption measurements for single and double-layer MPAs and through finite element simulation for MPA arrays.

Reliability and Performance Analysis of a Series-Parallel System Using Gumbel–Hougaard Family Copula

This research looks into the reliability metrics that are used to assess the strength of a solar system’s serial system, which is made up of four subsystems. Each subsystem consists of two parallel active components: two out of two photo-voltaic panels, one of two charge controllers, two of two batteries, and one of two inverters. Both the charge controller and the inverter have two human operators or switches. The Gumbel–Hougaard copula family was used to produce formulations of system dependability metrics such as reliability, mean time to failure (MTTF), availability, and profit function. Numerical examples are presented to show the obtained results and to investigate the impact of various system characteristics. The new study might help homes overcome some of the problems experienced by electric generation systems operating in hostile locations or under adverse weather conditions. A new model was developed, and solar photovoltaic system’s subsystems were analyzed in order to identify the most essential component. It was also indicated how to improve the system.

A new generalized Weibull-Gompertz distribution and its properties

In this paper, we proposed a new lifetime distribution called new generalized Weibull-Gompertz (NGWG) by considering a serial system with one component following a Weibull distribution and another following a generalized Weibull-Gompertz distribution. Several properties of the NGWG such as hazard function, moments, order statistics and maximum likelihood and Bayesian estimation are studied in this paper. A real data set is analyzed and it is observed that the present distribution can provide a better fit than some other well-known distributions such as modified Weibull and beta modified Weibull.

Reliability and performance prediction of a small serial solar photovoltaic system for rural consumption using the Gumbel-Hougaard family copula

Reliability and performance prediction of a small serial solar photovoltaic system for rural consumption using the Gumbel-Hougaard family copula

A serial system of multi-stage reverse electrodialysis stacks for hydrogen production

Salinity gradient energy is converted to hydrogen energy by integrating reverse electrodialysis (RED) and electrolysis of water to produce hydrogen. In this work, a serial system of multi-stage RED sacks is proposed to improve the energy efficiency and working performance of direct hydrogen production. The experimental results show that, compared with a single-stage system, the multi-stage RED stack system showed significant improvements in both hydrogen production and power output. Appropriately reducing the working current while increasing the number of RED stacks was beneficial to net power output and energy conversion. Total hydrogen production was almost unaffected when the number of RED stacks was large. Maximum energy conversion efficiency occurred at an optimal feed solution velocity. Under these conditions, the maximum net output power, total hydrogen production, and total energy-conversion efficiency were 2.06 W, 881.88 mL h−1, and 7.74%, respectively. The results are of relevance to investigation of the thermal-energy-driven reverse-electrodialysis heat engine for hydrogen production.

Development of Smart Earth Leakage Circuit Breaker Using IoT and Power Electronics

The Smart Earth Leakage Circuit Breaker research is based on IoT& power electronics-based protective switchgear for domestic consumers for the protection against earth leakage faults. In this paper, we have shown how to create a custom web server using HTML and CSS language and hosting this webserver to ESP module using Serial Peripheral Flash File System (SPIFFS). Along with protection against earth fault it provides, controlling of tripping current or fault current, monitoring voltage, power, current, power factor parameters of the connected load, monitoring fault parameters, Indicating the device status whether the ELCB is on or off, and the condition of ELCB it is in faulty condition or healthy condition and to let the user set the value of the tripping current on the webserver at which the ELCB must trip.

Determination of Micropulse Modes with Targeted Damage to the Retinal Pigment Epithelium Using Computer Modeling for the Development of Selective Individual Micropulse Retinal Therapy

ABSTRACT Purpose When using a serial laser system for selective impact on the retinal pigment epithelium (RPE), there is a challenge to determine the optimal range of micropulse parameters which result in targeted damage to the RPE. This study proposes a computer model that has identified the optimal parameters to be applied. Methods This study was conducted on 18 patients who were diagnosed with acute central serous chorioretinopathy and transparent optical media, aged 35 to 46 years old, and type 2 and 3 on the Fitzpatrick scale. Testing of the micropulse mode was performed on the Navilas 577s laser system; 864 spots were analyzed in total. Considering the probability of damage visualization at different laser power, the computer simulation of tissue heating and protein denaturation was performed to determine the micropulse modes which resulted in selective damage to the RPE. Results The computer model parameter ΔE = 3.34 × 105 J/mol was determined from fitting the model predictions to the autofluorescence test results. The micropulse modes with a micropulse duration of 50–100 µs, duty cycle 2.4–4.8%, 10 ms-pulse envelope (5 micropulses), and spot diameter of 100 µm have efficiency and selectivity above 67% and correspond to the optimal therapeutic window for targeted RPE damage at a certain power. Increasing the micropulse duration, number of micropulses, and duty cycle leads to a decrease in the selective effect on the RPE and higher damage to adjacent tissues. Conclusion The concepts of efficiency and selectivity have been introduced to quantify the amount of damage caused. The optimal range of micropulse parameters which result in effective and selective damage on the RPE has been determined for the Navilas 577s laser system. The proposed method can be used for any other serial laser system. A comparison of the different micropulse modes, as well as the CW modes, has been performed.

Managing a Hybrid RDC‐DC Inventory System

In this study, we study a hybrid RDC‐DC serial inventory system where the regional distribution center (RDC) replenishes its stock from an outside supplier (OS), while the distribution center (DC) faces random demand and replenishes its stock from the RDC. Unlike in the traditional serial system, the DC itself can replenish its inventory from outside as well. We firstly derive structural properties for the optimal long‐run average cost and the optimal stationary policy by vanishing discount approach, and then propose two simple and easy‐to‐implement policies. The first policy, which we call the three‐index policy, combines the characteristics of the echelon‐base‐stock policy for the serial system (Clark and Scarf. 1960. Management Sci.6(4): 475–490) and the dual‐index policy for the dual‐sourcing system (Veeraraghavan and Scheller‐Wolf. 2008. Oper. Res.56(4): 850–864). We show that the order‐up‐to level of the DC from the RDC can be computed by a newsboy fractile. A simulation‐based optimization procedure for the policy is provided. We then develop the approximate linear programming ( ALP) policy based on the three‐index policy and the multimodularity of the problem. This policy applies the linear programming approach to approximately solve the value function of the dynamic programming formulation. Numerical results show that both the three‐index policy and the ALP policy are comparable to the optimal policy computed via dynamic programming, and the latter performs slightly better. Moreover, the OS of the DC can draw considerable cost savings under both policies. We also conduct a numerical study with problem parameters calibrated using actual data from a consumer goods company in China to glen insights on the management of the system.

Energy, exergy, economic (3E) analysis, optimization and comparison of different ORC based CHP systems for waste heat recovery

ORC-CHP (combined heat and power based on organic Rankine cycle) systems have been widely adopted to recover low-grade heat. Economy, one of the advantages of ORC-CHP system, is optimized and compared in this paper. Three ORC-CHP systems are simulated and compared, including SS (serial system), the CS (the condensation system) and SS/CS (serial/condensation system). Energy-exergy-economic (3E) models for these cycles are developed, by using the genetic algorithm, the system performances are optimized with respect to the maximum profit ratio of investment (PRI). The result shows that the SS/CS has the highest PRI value under the considered working conditions. According to the results of economic analysis, the cost of the heat exchangers occupies the largest share in the three systems, all above 70%. When operated under optimal working conditions, most of the energy in the heat source is used to heat return water, leading to all three systems showing low electrical efficiency (less than 0.7%) and high thermal efficiency (more than 92%). Exergy analysis shows that most of the exergy destruction to the SS and the SS/CS occurs in hot water heaters, while for CS, it mainly occurs in the evaporator (67.48%) and then the condenser (31.35%).