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PurposeEnergy groups are cargo owners with large amounts of energy sources (such as coal) to transport. To achieve a satisfactory tradeoff between the reliability requirements of the sea transportation process and the need to control the investment cost, they usually set up a self-owned fleet supplemented by a chartered fleet. This paper aims to investigate the best fleet structure and to evaluate the investment scheme under volatile circumstances in the shipping market.Design/methodology/approachThe authors construct a mathematical model to determine the ratio of the self-owned fleet to the total fleet to minimize fleet operating costs. The volatility of both freight rates and oil prices is taken into consideration. The CPLEX solver is used to empirically analyze real data from an energy group in China, and the ship investment plan is evaluated considering the technical and economic feasibility.FindingsIf the ratio of the self-owned fleet to the total fleet is increased to the optimal of 90.40%, the total operating cost is reduced by 33.98%. Thus, the energy group should increase its capacity with a Panamax vessel of approximately 82,000 DWT. Purchasing a 5-year-old secondhand ship and building a new ship both have good investment return indicators.Originality/valueFor cargo owners engaging in transporting bulk cargo domestically in China, the suggested fleet ratio can provide a reference with a universal application scale, given the boundary economic conditions (including the volatility of freight rates and oil prices in the shipping market) in the paper.

In this article, a seven-level inverter based on bridge modular switched-capacitor circuits is presented. The inverter cannot only obtain dc–dc boosting conversion ability but also own capacitor voltage self-balance capability. Meanwhile, some of the switches can be operated under line voltage frequency, which makes the control strategy simpler and reduces the switching loss. More importantly, a new unequal amplitude carrier-based alternative phase opposition disposition pulsewidth modulation method is proposed to control the inverter, where the amplitude of the carrier wave will change based on the output voltage level. Under the proposed strategy, the inverter can output seven different voltage levels and the capacitor voltage self-balance can be realized during the switching period, the quality of the output waveforms can be improved remarkably. Last, a loss analysis within the two time-scale of switching period and 1/4 line voltage period is presented to give the loss insight. The simulation and experimental results verify the correctness and practicability of these analyses.

This study identifies a unique bias faced by Black employees which makes it challenging for this group to manage their professional image. Integrating research on racial backlash, image management, and expectancy violation theory, we argue that self-promotion by Black employees will result in detrimental outcomes for this group compared to White, Hispanic, and Asian employees. Due to negative racial stereotypes related to their job competence, we hypothesize that self-promotion by Black employees will be viewed by their White managers as a violation of stereotypically appropriate behavior and will result in a backlash in the form of lower job-related outcomes. We propose that the process by which these effects occur is through manager assessments of their employees on agentic and communal traits. Our hypothesized model was tested with a stratified sample of manager-employee dyads of a large financial institution. Results indicated that self-promotion by Black employees was associated with lower job performance and person-organization fit ratings, as well as fewer idiosyncratic deals with their immediate managers compared to White, Hispanic, and Asian employees. Implications of the divergent consequences of self-promotion for Black employees relative to other racial groups are discussed. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Steeping process is an important factor for aroma release of tea, which has rarely been investigated for the aroma changes of raw Pu-erh tea (RAPT). In addition, the comprehensive aroma characteristics identification of RAPT infusion is necessary. In this study, GC-IMS coupled with principal component analysis (PCA) was used to clarify the difference of volatile profiles during the steeping process of RAPT. Furthermore, the volatiles contained in the RAPT infusion were extracted by three pretreatment methods (HS-SPME, SBSE, and SAFE) and identified using GC-O-MS. According to the odor activity value, 28 of 66 compounds were categorized as aroma-active compounds. Aroma recombination and omission experiments showed that "fatty", "green", "fruity", and "floral" are considered to be the main aroma attributes of RAPT infusion with a strong relationship with 1-octen-3-one, 1-octen-3-ol, (

Swertia mussotii Franch. has been widely used in Tibetan folk medicine as an important drug ingredient for the treatment of hepatitis and hepatobiliary disease and for homeopathic purposes. But the lacking natural resources of S. mussotii is becoming more obvious with increasing market demands. The main objective of this work was to examine genetic differentiation among S. mussotii populations from different geographical locations and use the knowledge gained to facilitate future selection of the species suitable for large-scale cultivation to meet the increasing demand for medicinal use of this plant. In this study, 68 S. mussotii Franch samples collected from Zhongda (16), Chengduo (16), and Xiewu (8) County in Qinghai Province, Xiaojin (14) and Jinchuan (14) County in Sichuan Province, China and 4 samples from related species, were genotyped using genotyping-by-sequencing (GBS) technique. GBS scored 4095 SNPs with a minor-allele frequency > 0.25 and an average read depth

Recognizing the dynamic nature of affect, we consider observed leader affect and its variability as important social signals that jointly impact employees’ daily affective reactions and work engagement. Integrating the emotion as social information model and adaptation-level theory, we hypothesized that the impact of daily observed leader affect on employees’ affect and subsequent work engagement is moderated by observed leader affect variability. To test the model, an experience sampling method (ESM) involving two surveys per day over 10 days was employed with a sample of 75 employees. Results indicated that observed leader affect variability weakened the positive relationship between observed leader positive affect and employee work engagement via employee positive affect. Also, observed leader negative affect was negatively related to employee work engagement via employee negative affect, but this indirect effect was not moderated by observed leader affect variability. Our results highlight the critical role of observed leader affect variability in understanding leaders’ affective influence on employee affect and engagement.

Prefabrication as a sustainable construction method has become a trend for use in house construction. However, the construction of rural houses in China still mainly adopts on-site construction, which also raises wasteful resources and environmental problems. Previous studies lack an evaluation system for the implementation potential of prefabricated rural housing in counties, and thus cannot provide references for the government to formulate implementation strategies. This study uses PEST analysis to establish an evaluation index system for the implementation potential of prefabricated rural housing and then evaluates 32 counties in Chongqing with urbanization rates below 90% based on the entropy weighted TOPSIS model. The results show that the weight values of the four evaluation subsystems of political, economic, social, and technological are 0.4516, 0.3152, 0.0684, and 0.1648, respectively; the nearness degrees of Dianjiang, Yubei, Jiangjin, and Rongchang are 0.5475, 0.4439, 0.4312, and 0.4103, respectively, ranking in the top four in Chongqing. The results indicate that the potential of implementing prefabricated rural housing in Chongqing is closely related to policy orientation and construction industrialization; Dianjiang, Yubei, Jiangjin, and Rongchang have the relative advantage of implementing prefabricated rural housing. Finally, this paper proposes political, economic, social, and technological suggestions for the implementation of prefabricated rural housing in Chongqing.

In the context of internships, we develop and test theory regarding the relationship between interns' happiness and their perceptions of leader-member exchange (LMX). Adopting a discrete and dynamic emotions perspective, we examine interns' happiness that is elicited by the most memorable daily interactions with their supervisor and bring attention to the construct of happiness variability (i.e., between-person differences in the fluctuation of happiness over time). Integrating Affective Events Theory and Feelings as Information Theory, we theorize and investigate how interns' happiness variability interacts with their psychological resources (i.e., optimism and core self-evaluation) to inform their perceptions of LMX, and ultimately, is indirectly associated with interns' job-seeking goals related to future employment with the organization. Findings from our daily field study reveal a positive relationship between happiness variability and LMX among interns low in optimism and interns low in core self-evaluation. The findings also provide evidence of a conditional indirect relationship between interns' happiness variability and a key employment outcome, job-seeking goals, via their perceptions of LMX. Extending our results, we discuss theoretical and empirical implications for future research and practice.

To obtain the direction and distance of the electrical interface in the sea, the active electric field of the electric dipole and two three-component electric field intensity sensors are used to detect them. First, the structure design of the active electric field detection device is given, and then a method for active electric field detection of the electrical interface in the sea area is proposed, that is, the effect of the electrical interface on the active electric field is equivalent to the effect of the mirror electric dipole, locating the position of the mirror dipole can be done by measuring the change of the field strength, and then the interface parameters can be determined according to the symmetrical relationship between the position of the mirror dipole and the source dipole. Both simulation analysis and laboratory test results show that the interface detection method is feasible. The related research provides new ideas for target detection in the sea.

Combining ro-ro shipping and tractor-and-semitrailer swap transport under land-sea combined transportation can reduce operating costs and improve the safety of maritime transport. In additi...

A novel high step-down dc–dc converter with voltage demultiplier cell is proposed in this paper, which is widely used in the high step-down applications such as electric vehicle and digital circuits. The combination of switched-capacitor and coupled-inductor is employed to build extended voltage demultiplier in the proposed converter, which makes a quite higher voltage conversion ratio than that of the existing counterparts. Thus, the proposed converter can achieve extremely low output voltage with an appropriate duty ratio, and the extreme duty cycle is avoided. Accordingly, voltage stress on power switches is greatly reduced. Then, mosfet s with low conduction resistance could be utilized to reduce conduction loss. Importantly, zero-voltage switching could be achieved for the main switch, which promotes the conversion efficiency further. In addition, the coupled inductor operates not only as a filter inductor, but also as a transformer when the main switch is in the off state, which reduces the volume of the magnetic core and improves the power density of the converter. The operation principle, performance analysis, design considerations of the proposed converter and performance comparison with recent counterparts are discussed in detail, and finally, an experimental prototype is built to verify the theoretical analysis and performance of the proposed converter.

In high gain voltage conversion applications, the low-side switches usually suffer large current stress, resulting in dominate switching loss. In this paper, a general soft-switching method based on an advanced interleaved high-step-up converter, which features excellent performance but works in hard-switching, is presented to combat this issue by using a plug-play resonant circuit. Under this soft-switching method, the main switches reach zero-voltage switching (ZVS) turn- on and ZVS turn- off , and the soft-switching condition is derived. Meanwhile, the added auxiliary switches could be turned off under ZVS condition and turned on under zero-current switching condition as well. More importantly, due to its location out of the energy transferring path, the auxiliary circuit will never lead gain lost to the converter and maintain its other existing merits, such as current auto-balancing and diode inverse-recovery well. A 1-kW prototype is built and tested to verify the significant efficiency improvement and merits maintenance for the proposed converter considering active resonant soft switching.

Heterogeneous Fleet and Multi-Depot Static Bike Rebalancing Problem with Split Load (HFMDSBRP-SD) is an extension of the Static Bike Rebalancing Problem, considering heterogeneous fleet multiple depots, allowing split load. It consists of finding a set of least-cost repositioning vehicle routes and determining each station’s pickup or delivery quantity to satisfy the demand of each station. We develop a branch-and-price-and-cut (BPC) where a tabu search column generator and a heuristic label-setting algorithm are introduced to accelerate the column generation procedure, the subset-row (SR) inequalities, the strong minimum number of vehicles (SMV) inequalities, and the enhanced elementary inequalities are extended fitting this problem and applied to speed up the global convergence rate. Computational results demonstrate the effectiveness of the BPC algorithm. Among 360 instances with a maximum size of 30, there are 298 instances capable of achieving optimality within two hour time limitation.

Drawing upon social comparison theory, we developed and tested a model to examine potential negative coworker reactions toward proactive employees. We theorized that a focal employee's proactive personality is positively related with his or her high relative standing in the group, which in turn exposes him or her to being the target of coworker envy. This may then reduce the focal employee's received help from coworkers and give rise to coworker undermining. We further reasoned that employee prosocial motivation moderates the serial mediated relationships. Our hypotheses were generally supported in 3 field studies involving a total of 1,069 employees from 223 groups. Proactive personality was negatively and indirectly related to received help from coworkers, via relative leader-member exchange (RLMX) and relative job performance, and then via being envied by coworkers (Study 1). Results also generally supported the positive and indirect effect of proactive personality on coworker undermining via the same set of sequential mediators (e.g., RLMX and then being envied, Study 2). The indirect effects of proactive personality on coworker helping and undermining (e.g., via relative job performance and coworker envy) were only significant when employees' prosocial motivation was low (Study 3). This research contributes to a more complete and balanced theorization of the influences of proactive personality in organizations. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

In response to the replication crisis, many psychologists recommended that the field adopt several proposed reforms to research practices, such as preregistration, to make research more replicable. However, how researchers have received these proposals is not well known because, to our knowledge, no systematic investigation into use of these reforms has been conducted. We wanted to learn about the rationales researchers have for not adopting the proposed reforms. We analyzed survey data of 1,035 researchers in social and personality psychology who were asked to indicate whether they thought it was acceptable to not follow four specific proposed reforms and to explain their reasoning when they thought it was acceptable to not adopt these reforms. The four reforms were preregistering hypotheses and methods, making data publicly available online, conducting formal power analyses, and reporting effect sizes. Our results suggest that (a) researchers have adopted some of the proposed reforms (e.g., reporting effect sizes) more than others (e.g., preregistering studies) and (b) rationales for not adopting them reflect a need for more discussion and education about their utility and feasibility.

The field of organizational psychology is currently in what some scholars have referred to as an affective era (Judge et al., 2017) and have called for examinations of discrete emotions at work. In...

Servant leadership, which prioritizes the interests of followers and other shareholders, is considered as a unique approach that offers much potential to enrich our understanding of leadership. Des...

In this paper, the design and measurements of a 5-6GHz high-efficiency MMIC high power amplifier implemented in a $\mathbf{0.25}\mu\mathbf{m}$ GaN HEMT process was described. The MMIC has been designed using 2-stage topology. At 5-6GHz, the MMIC showed a power-added efficiency (PAE) of 44%-52% with an associated gain over 20dBm and an output power of 35dBm. The MMIC achieved above 50% PAE at 5.3-5.6GHz. The key to this design is determining and matching the optimum source and load impedance for PAE at the first three harmonics in output stage in order to improve the PAE.

Supplemental material, WashburnOpenPracticesDisclosure for Why Do Some Psychology Researchers Resist Adopting Proposed Reforms to Research Practices? A Description of Researchers’ Rationales by Anthony N. Washburn, Brittany E. Hanson, Matt Motyl, Linda J. Skitka, Caitlyn Yantis, Kendal M. Wong, Jiaqing Sun, J. P. Prims, Allison B. Mueller, Zachary J. Melton and Timothy S. Carsel in Advances in Methods and Practices in Psychological Science

There are some experience rules accumulated by good managers and operators in some factories. However, these rules gradient are often too rough to realize the fine production management. In this paper, the characteristics of ore terminal handling technology system is analyzed, and the key factors that influence harbor handling cost, handling efficiency and handling equipment operating parameters are established. Based on above, the optimization model of handling equipment configuration that avoids improving equipment utilization with the cost sacrificing is built. Moreover, the fuzzy rules are deduced by the model, through the on-the-spot investigation, using the actual data of Port A to optimize the handling equipment configuration, and finally build a new handling equipment configuration rules that enrich and further refine the existing rules of expert experience. The optimized fuzzy rules can be more accurately adjusted handling equipment configuration scheme online according to the change of operating condition, which concise and ease of use are more suitable to real-time production scheduling of terminal in order to achieve the refinement of production management.

The scientific quality of social and personality psychology has been debated at great length in recent years. Despite research on the prevalence of Questionable Research Practices (QRPs) and the replicability of particular findings, the impact of the current discussion on research practices is unknown. The current studies examine whether and how practices have changed, if at all, over the last 10 years. In Study 1, we surveyed 1,166 social and personality psychologists about how the current debate has affected their perceptions of their own and the field's research practices. In Study 2, we coded the research practices and critical test statistics from social and personality psychology articles published in 2003-2004 and 2013-2014. Together, these studies suggest that (a) perceptions of the current state of the field are more pessimistic than optimistic; (b) the discussion has increased researchers' intentions to avoid QRPs and adopt proposed best practices, (c) the estimated replicability of research published in 2003-2004 may not be as bad as many feared, and (d) research published in 2013-2014 shows some improvement over research published in 2003-2004, a result that suggests the field is evolving in a positive direction. (PsycINFO Database Record

Two studies were conducted to replicate and extend previous findings on the effect of uncooperative behavior on group cooperation (the “bad apple” effect). Study 1 (56 women, 40 men; M age = 23.5 yr.) manipulated information about contributions from the bad apple, controlling for overall contributions to a group account. Study 2 (50 women, 34 men; M age = 20.4 yr.) compared the effects of a bad apple and a good apple on cooperation. The social value orientation of participants was measured to explore individual differences in the bad apple effect. The results revealed a bad apple (a) decreased cooperation among individuals with proself and prosocial orientations in Study 1, and (b) had a greater effect than a good apple on those who were proself compared to prosocial in Study 2.

The current research examined Chinese parents’ motivation regarding music training for their children, and its relationships with their children’s learning outcomes ( N = 269). Results of principal component analysis showed that Chinese parents had both intrinsic and extrinsic motivation regarding children’s music training. Parents’ intrinsic motivation was positively related to children’s learning achievement (rated by teachers). Although extrinsic motivation did not predict learning achievement, it served as a significant moderator and strengthened the relationship between intrinsic motivation and children’s achievement. Moreover, the results showed that children’s learning engagement mediated the interaction between intrinsic motivation and extrinsic motivation regarding children’s learning achievement. The corresponding moderated mediation model was supported. Theoretical and practical implications are discussed.