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In the context of increasingly prominent product personalization and customization trends, intelligent manufacturing-oriented turnkey projects can provide manufacturers with fast and convenient turnkey services for manufacturing systems. Their key characteristic is the transformation of the traditional design process into a configuration process. However, the scope of configuration resources in existing research is limited; the cost and time required for manufacturing system construction are overlooked; and the integration of the system layout configuration is rarely considered, making it difficult to meet the manufacturing system configuration requirements of turnkey projects. In response, this study establishes a multi-factor integrated rapid configuration model and proposes a solution method for manufacturing systems based on the requirements of turnkey projects. The configuration model considers the system construction cost and duration and the product manufacturing cost and duration, as optimization objectives. The differences in product feature-dividing schemes and configuration of processes, equipment, tools, fixtures, and layouts were considered simultaneously. The proposed model-solving method is a three-layer hybrid optimization algorithm framework with two optimization algorithm modules and an intermediate algorithm module. Four hybrid configuration algorithms are established based on non-dominated sorting genetic algorithm-III (NSGAIII), non-dominated sorting genetic algorithm-II (NSGAII), multi-objective simulated annealing (MOSA), multi-objective neighborhood search (MONS), and tabu search (TS). These algorithms are compared and validated through a hydraulic valve block production case, and the TS and NSGAIII (TS-NSGAIII) hybrid algorithm exhibits the best performance. This case demonstrates the effectiveness of the proposed model and solution method.

The exploration of component states for optimizing maintenance schedules in complex systems has garnered significant interest from researchers. However, current literature usually overlooks the critical aspects of system flexibility and reconfigurability. Judicious implementation of system reconfiguration can effectively mitigate system downtime and enhance production continuity. This study proposes a dynamic condition-based maintenance policy considering reconfiguration for reconfigurable systems. A double-layer decision rule was constructed for the devices and systems. To achieve the best overall maintenance effect of the system, the remaining useful life probability distribution and recommended maintenance time of each device were used to optimize the concurrent maintenance time window of the devices and determine whether to reconfigure them. A comprehensive maintenance efficiency index was introduced that simultaneously considered the maintenance cost rate, reliability, and availability of the system to characterize the overall maintenance effect. The reconfiguration cost was included in the maintenance cost. The proposed policy was tested through numerical experiments and compared with different-level policies. The results show that the proposed policy can significantly reduce the downtime and maintenance costs and improve the overall system reliability and availability.

Abstract:Collections of Batrachospermales from 13 stream sites in North America (Canada and United States), Europe (Spain) and Asia (China) were examined. Phylogenetic analyses of sequences data from the plastid-encoded ribulose 1,5-bisphosphate carboxylase/oxygenase large subunit gene (rbcL) and the mitochondrial-encoded cytochrome oxidase 1 gene barcode region (COI-5P), along with morphological studies, suggested that these collections represent new taxa. Three species in a proposed new genus Volatusare described: V. carrionii sp. nov., V. personatus sp. nov. and V. ulterior sp. nov. Four new species of Batrachospermum sensu strictoare also described: B. dapsile sp. nov., B. naiadis sp. nov., B. pozoazulense sp. nov. and B. shanxiense sp. nov. Taxa proposed based on the molecular analyses were in many cases difficult to distinguish with unique morphological characters. The new genus Volatusshares the distinctive characteristic of twisted or curled carpogonium-bearing branches with Kumanoaand Tuomeyabut was not sister to either of these genera, suggesting that this character may have arisen at least three times in the order. The three species of Volatuswere distinguished from each other based on molecular data and, in part, geographic distribution. The proposed Batrachospermumspecies B. naiadis sp. nov., B. pozoazulense sp. nov. and B. shanxiense sp. nov. overlap in both vegetative and reproductive characters with each other and B. gelatinosum. Batrachospermum dapsilehad a distinguishing character of monosporangia in clusters arising from the periaxial or proximal cells and terminal or subterminal on primary fascicles.

VisM.L., FengJ., ChiassonW.B., XieS.-L., StanchevaR., EntwisleT.J., ChouJ.-Y. andWangW.-L. Investigation of the molecular and morphological variability in Batrachospermum arcuatum(Batrachospermales, Rhodophyta) from geographically distant locations. Phycologia49: 545–553. DOI: 10.2216/10-04.1Phylogeographic patterns in Batrachospermum arcuatumwere investigated using the mitochondrial intergenic spacer between the cytochrome oxidase subunit 2 and 3 (cox2-3 spacer) from locations worldwide. Sixteen locations were sampled in six regions as follows: three locations in Bulgaria, two in China, three in the northwestern United States, one in New Zealand, six in Hawaii and one in Taiwan. Sequencing of 107 individuals resulted in 12 haplotypes. In the United States and Bulgaria, there was considerable sequence divergence among haplotypes. Likewise in the Hawaiian Islands, there was variation among haplotypes, and each island appeared to have a single haplotype represented. Three closely related haplotypes were present at the Taiwan location. The New Zealand sample was identical to one of the haplotypes from the northwestern United States. Individuals representing the 12 cox2-3 spacer haplotypes were sequenced for the rbcL gene. In the combined analysis, the Hawaii and Taiwan samples were a well-supported clade as were two Bulgaria samples. The US and New Zealand haplotypes formed a well-supported clade and likewise the China samples, but the relationship of the third Bulgaria haplotype to these others was unresolved. The specimens showed morphological variation among localities and regions, but no morphological features appeared to be diagnostic of the molecular results. Batrachospermum arcuatumappears to be a widespread taxon with considerable morphological plasticity that does not coincide with the substantial molecular variation. Alternatively, B. arcuatummay harbour cryptic species. There appears to be a temperate origin of the taxon and a derived group of haplotypes from tropical regions.

In diesem Artikel wird eine Übersicht über die Characeen-Literatur aus China und eine Liste aller in diesem Land gefundenen Arten gegeben. Die Liste folgt Han & Li (1994). Aus China sind bisher insgesamt 159 Arten und 44 Varietäten von Characeen bekannt. Die Artenzahlen der verschiedenen Gattungen sind wie folgt (in Klammern die endemischen Arten): Nitella 90(40), Tolypella 6(3), Nitellopsis 1, Lamprothamnium 1, Lychnothamnus 2(1) und Chara 59(26). Darüber hinaus wird die geographische Verbreitung der einzelnen Gattungen in der Volksrepublik China in Karten angegeben.