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International audience; In the last two decades, maintenance as an essential method to prevent machine breakdown has achieved undoubted importance in process industries and manufacturing systems. With ever increasing high-quality products demand, the number of tool change or machine maintenance become quite remarkable. Besides, industry 4.0 supports manufacturing enterprises to explore more efficient and intelligent scheduling modes. Machine periodic maintenance has a significant impact on the scheduling of many manufacturing companies, it therefore has become one of the factors they must consider. Despite this, theoretical analysis for the machine scheduling problem with periodic maintenance has not received considerable critical attention in previous studies. Motivated by scheduling practice, this work revisits a single machine scheduling problem with periodic maintenance to minimize the number of tardy jobs. First, a polynomial-time solvable case is identified. Then we propose a dynamic programming algorithm to solve the general case. At last, the non-approximability is proven.

Despite the emphases on computability issues in research of algorithmic game theory, the limited computational capacity of players have received far less attention. This work examines how different levels of players' computational ability (or "rationality") impact the outcomes of sequential scheduling games. Surprisingly, our results show that a lower level of rationality of players may lead to better equilibria. More specifically, we characterize the sequential price of anarchy (SPoA) under two different models of bounded rationality, namely, players with $k$-lookahead and simple-minded players. The model in which players have $k$-lookahead interpolates between the "perfect rationality" ($k=n-1$) and "online greedy" ($k=0$). Our results show that the inefficiency of equilibria (SPoA) increases in $k$ the degree of lookahead: $\mathrm{SPoA} = O (k^2)$ for two machines and $\mathrm{SPoA} = O\left(2^k \min \{mk,n\}\right)$ for $m$ machines, where $n$ is the number of players. Moreover, when players are simple-minded, the SPoA is exactly $m$, which coincides with the performance of "online greedy"., Comment: Extended abstract to appear in WINE 2020

The mutations of BRCA1 and p53 genes have been simultaneously characterized in many tumors. However, their coexpression and associations have not been investigated quantitatively in prostate cancer. In the present study, the expressions of the mutated BRCA1 mRNA and p53 mRNA were examined in 48 Chinese prostate cancer cases and 10 corresponding adjacent benign tissues with in situ hybridization. The 5-year survival rates of the corresponding patients after operation were investigated. The results showed that the positive expressions of the mutated BCRA1 mRNA and p53 mRNA are involved in prostate cancer (P < 0.05). Moreover, there is a closed negative association between the expressions of the mutated BRCA1 gene and p53 gene in the mRNA level with the progression, angiogenesis, metastasis, and survival rate of prostate cancer. Their coexpression and negative association suggest that the two altered tumor suppressor genes might interact functionally in prostate cancer to provide a potential signal determining a prognosis of the tumor metastasis and survival rate. Further work will be done to elucidate the interaction mechanisms in prostate cancer.

In the problem of online time series search introduced by El-Yaniv et al. (2001) [1], a player observes prices one by one over time and shall select exactly one of the prices on its arrival without the knowledge of future prices, aiming to maximize the selected price. In this paper, we extend the problem by introducing profit function. Considering two cases where the search duration is either known or unknown beforehand, we propose two optimal deterministic algorithms respectively. The models and results in this paper generalize those of El-Yaniv et al. (2001) [1].

Taking into account the uncertain delay of work on the critical path, the online strategy and competitive analysis are introduced into time-cost optimizing in project management. The competitive ratio of the strategy is given, and the prerushing strategy is proved to be the best determinate one. The relationship between the general strategy and the optimal offline strategy is analyzed, and three properties are discovered. On this basis, this article designs the risk-tolerance strategy and proves its competitive ratio to help the project manager in choosing the optimal strategy according to his own risk tolerance and forecast.

The weighted arithmetical mean complex judgement matrix (WAMCJM) is the most common method for aggregating group opinions, but it has a shortcoming, namely the WAMCJM of the perfectly consistent judgement matrices given by experts canot guarantee its perfect consistency. An upper bound of the WAMCJM's consistency is presented. Simultaneously, a compatibility index of judging the aggregating extent of group opinions is also introduced. The WAMCJM is of acceptable consistency and is proved provided the compatibilities of all judgement matrices given by experts are smaller than the threshold value of acceptable consistency. These conclusions are important to group decision making.

Let F be a set of n (n being an even number) fixed points and let M be a set of n / 2 -1 moving points, whose locations are to be determined, in the plane. A topology is a set of edges connecting these points in the set V=F\cup M . Let E be a full 4-degree Steiner topology; i.e., the topology forms a tree which contains fixed points of degree 1 and moving points of degree 4, and let H(E) be a set of topologies which include E and its degeneracies. We define a canonical tree over V as one whose topology belongs to H(E) and in which the sum of two adjacent angles around any node is not less than π . In this paper we prove that if a canonical tree exists, then it is the shortest (degree-4) network under a given topology E . We present an O(n2) time algorithm for finding a degree-4 shortest network whose topology belongs to H(E) .

LetT denote a finite set of points in a unit isoscele right triangle (i.e., the right sides are both one),f(T) the minimum distance between pairs of points ofT, and $$f\vartriangle (n) = \mathop {\max }\limits_{||T|| = n} f(T).$$ In this paper, the exact values off Δ (n) for 2≤n≤7 and the corresponding configurations are given.

Protein derived from blue mussel (Mytilus edulis) was hydrolysed using four kinds of proteases (pepsin, papain, neutrase and alcalase), and the neutrase hydrolysate (BNH) obtained by 3-h hydrolysis exhibited the highest 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity compared to other hydrolysates. By using ultrafiltration, gel filtration chromatography and reversed phase high performance liquid chromatography (RP-HPLC), a novel antioxidant peptide (BNH-P7) was isolated from BNH, and its amino acid sequence was identified as YPPAK (Tyr-Pro-Pro-Ala-Lys) with molecular weight of 574 Da. BNH-P7 exhibited good scavenging activity on DPPH radical, hydroxyl radical, and superoxide anion radical with EC(50) of 2.62, 0.228, and 0.072 mg/ml, respectively. BNH-P7 was also effectively against lipid peroxidation in a linoleic acid model system. The high activity of BNH-P7 was due to the small size and the presence of antioxidant and hydrophobic amino acid residues (Tyr and Pro) within its sequence.

In the present study, the preparation process of the antioxidant hydrolysate and fractions from Mytilus edulis by papain were studied. The optimal conditions of papain hydrolysis was obtained by single-factor experiments and orthogonal test with the DPPH· scavenging ratio as index. Under the optimal hydrolysis conditions of the temperature 65 °C, pH 7.0, enzymatic hydrolysis time 3 h and amount of enzyme 1.0 %, the high DPPH radical scavenging activity (28.74) of the total hydrolysate was obtained. The fraction F2 with the highest antioxidant activity was collected using Sephadex G-25 column from the total hydrolysate, with the reducing power, ·OH and DPPH· scavenging ratio being 0.807, 10.44 % and 31.4 % at the concentration of 5 mg/ml. The results revealed that the enzymatic hydrolysis method was appropriate for obtaining the product with the high antioxidant activity from the mussel protein and the F2 mainly contributed to the antioxidant activities of the total hydrolysate.