This paper addresses the issue of energy-efficient trajectory optimization for planetary surface manipulators under kinematic and dynamic constraints. To mitigate the inefficiency of existing algorithms, an adaptive boundary adjustment strategy for the multi-dimensional decision space is proposed, which modifies the time intervals between neighboring configuration nodes, enabling precise adaptation of the decision space boundaries. Additionally, a complementary dual-archive guided boundary exploration strategy is introduced to connect the feasible and infeasible regions, allowing for the effective utilization of information from infeasible solutions near the constraint boundaries. This heuristic approach guides the particle swarm in efficiently exploring areas close to the constraints, significantly enhancing the evolutionary optimization capability of the swarm. Furthermore, a swarm optimal position updating strategy based on sparsity sorting is developed. This guides the particle swarm to concentrate on exploring positions where non-dominated solutions on the Pareto front are more sparsely distributed, ensuring uniformity and completeness in the final Pareto front. Finally, the aforementioned strategies are integrated into a heuristic multi-objective particle swarm optimization (HMOPSO) algorithm for the trajectory optimization of manipulators. Comparative experiments are conducted with HMOPSO and existing advanced algorithms in the field of multi-objective optimization. Experimental results demonstrate that HMOPSO exhibits superior evolutionary optimization capabilities and faster convergence rates. Moreover, performance metrics such as inverse generation distance and dominant area during the iterative process of HMOPSO significantly outperform those of existing optimization algorithms.

To investigate the environmental history of the Tisza River (Hungary), we applied 14C and OSL dating methods for five parallel, neighboring cores from the flood plain area (Jászság Basin). Four major sedimentary layers were identified: meadow soil on the top (S1); silty-clay (S2); clayey-silt (S3) section; and fine sand (S4). 14C and OSL data were integrated into a synthetic age-depth model using the BACON software package. Formation of the S1 layer (depth: 0–1.0 m) falls in the Holocene, up to 10 kyrs cal BP, with moderate sedimentation rate (100 yr/cm aAR). The S2 layer (1.0–8.0 m depth) represent the entire Last Glacial to Upper Pleniglacial period (19–27 kyrs cal BP), with a much faster sedimentation (20 yr/cm aAr). The S3 section (8.0–17.0 m) represents a longer period (27–45 kyrs cal BP) with similar sedimentation rate (19 yr/cm aAr) as S2. These clayey silt layers fall into the Late Pleistocene/Middle Pleniglacial period, a period of nearly 18 kyrs of sedimentation resulting ∼9 m thick sediment. Our study delivered some new and important details about the surface evolution of the investigated Tiszasüly area. A missing part of about 10 kyrs period (between 10–19 kyrs cal BP) was revealed in the investigated synthetic cores.

This article estimates several causal counterfactual parameters of the effect of being an Historically Black College/University (HBCU) on college/university endowment, and on the probability of a college/university failing as a function of its financial health, which is proportional to endowment. Our various counterfactual causal parameter decomposition estimates suggest that the racial distinctiveness of HBCUs causes, and can account for cumulative HBCU/non-HBCU endowment disparities between $11.5 billion and $58.9 billion for the HBCUs in our estimating sample. This is consistent with, at least in part, racial discrimination against HBCUs in philanthropic endowment contributions/gifts. With respect to failure, as HBCU status contributes to higher failure probabilities that are a function of college/university financial health, reducing the HBCU/non-HBCU endowment disparity would also enhance the ability of HBCUs to continuously exist. We suggest two public policy interventions to close the endowment disparity. First, increase the tax subsidy for contributions/gifts to HBCUs relative to non-HBCUs, as a way to incentivize more gifts to HBCUs from wealthy foundations and individuals. Secondly, to the extent that the wealth of HBCU alumni—who give back to their alma mater at higher rates than their non-HBCU peers—has been constrained due to the legacy of Slavery and discrimination, a distribution of reparations to the descendants of Black American Slaves would close Black-White wealth disparities that could translate into larger endowment contributions/gifts from HBCU alumni.

I worked directly for Hans Zell from 1984 to 1995. I had been seeking a change of career after a move to Oxford, and saw the advertisement by Hans Zell Publishers, exactly matching what I sought – publishing, books, with the bonus of Africa. That job informed the rest of my working life.

Let $(X_t)_{t \geqslant 0}$ be the solution of the stochastic differential equation

\[\mathrm{d} X_t = b(X_t) \,\mathrm{d} t+A\,\mathrm{d} Z_t, \quad X_{0}=x,\]

$b\,:\, \mathbb{R}^d \rightarrow \mathbb{R}^d$

$A \in \mathbb{R}^{d \times d}$

$(Z_t)_{t\geqslant 0}$

$\alpha$

$\alpha \in (1,2)$

$x\in\mathbb{R}^{d}$

$\Gamma = (\gamma_n)_{n\in \mathbb{N}}$

$(X_t)_{t \geqslant 0}$

$\alpha$

$\gamma^{\frac{1}{\alpha}}_n$

$\gamma^{1+\frac {1}{\alpha}-\frac{1}{\kappa}}_n$

$\kappa \in [1,\alpha)$

$\gamma^{\frac{2-\alpha}{\alpha}}_n$

$\alpha$

This paper reconsiders long-standing debates in Canada about the relationship between language, race, and culture. Federal policies focused on official bilingualism (1969) and multiculturalism (1971) animated local movements of parents, students, and other community members demanding greater linguistic and racial inclusion in schools. This paper examines two instances of these grassroots politics, namely activism on behalf of heritage-language education and Black cultural-heritage programs, in Toronto, Ontario, between 1970 and 1987. Our analysis reveals key instances in which temporary forms of solidarity emerged between heritage-language and Black activism, as well as contradictory trajectories in this activism that undermined what Roseann Liu and Savannah Shange have theorized as “thick solidarity.” In this paper, we argue that absences of thick solidarity ultimately weakened efforts by heritage-language and Black activists alike to reorganize schools in ways that were more linguistically and racially just.

This article engages with the burgeoning literature on the conceptualization of corruption, a literature animated by the view that failures in anticorruption practice—the limited progress made in tackling global corruption—are in part a consequence of the ways in which corruption is theorized by academics. In response, the article proposes and elaborates a four-dimensional definition of corruption with detailed subdefinitions and seeks to advance thinking in both academic and practitioner circles on how corruption can be most effectively identified in context. The article makes five distinct contributions to live debates in the conceptual literature and clarifies several ambiguities and disagreements that have arisen within it.

First, it presents a set of grounded subdefinitions that make explicit the scope of each dimension of the definition. Second, it recommends applying the four dimensions in a predetermined sequence, enabling uncertainties or gray areas in each dimension to be resolved and clarified by subsequent dimensions. Third, it addresses the much-contested “abuse” dimension, acknowledging not only the flexibility required to identify abuses in different political and social settings but also the need to limit the scope of abuse so that it is not wholly idiosyncratic or relative. Fourth, it incorporates systemic and institutional forms of corruption, which creates an important bridge between individual and institutional approaches to corruption. Finally, it offers a defense for integrating the notion of public interest into the definition, which not only provides additional clarity to the conceptualization but also does justice to the reasons we care about corruption in the first place.

We show that for all real biquadratic fields not containing $\sqrt{2}$, $\sqrt{3}$, $\sqrt{5}$, $\sqrt{6}$, $\sqrt{7}$ and $\sqrt{13}$, the Pythagoras number of the ring of algebraic integers is at least 6. We also provide an upper bound on the norm and the minimal (codifferent) trace of additively indecomposable integers in some families of these fields.

We construct a Divisia money measure for U.K. households and private non-financial corporations and a corresponding dual user cost index employing a consistent methodology from 1977 up to the present. Our joint construction of both the Divisia quantity index and the Divisia price dual facilitates an investigation of structural vector autoregresssion models (SVARs) over a long sample period of the type of non-recursive identifications explored by Belongia and Ireland (2016, 2018), as well as the block triangular specification advanced by Keating et al. (2019). An examination of the U.K. economy reveals that structures that consider a short-term interest rate to be the monetary policy indicator generate unremitting price puzzles. In contrast, we find sensible economic responses in various specifications that treat our Divisia measure as the indicator variable.

Writing a tribute to Hans Zell is, as I realize while writing, both a personal exercise, a demanding task of research, and, above all, a profound continuation of meaning in relation to a person I admire and consider a friend. These are the reasons why I accepted without hesitation the invitation from Stephanie Kitchen and Terry Barringer to write this tribute. It is, therefore, both an honour and a considerable challenge for me to write this ‘selective’ retrospective, especially as Hans continues to develop his work and to offer new valuable articles and in-depth analyses. It is fascinating, and certainly unique, to think that Hans has been tirelessly publishing his work since 1964. I am also convinced that he will hate reading such a tribute, given that he has always preferred to highlight the work of others and encourage them to follow their own path. I will therefore take full responsibility for this, never mind!

This article explores the commentaries on Analects 3.5 and related texts in light of Confucius’ other discussions of the Yi Di. It also speculates on the ways readings of these texts have been shaped by the historical-cultural contexts of the scholars who have interpreted them over the years. Finally, it questions whether there might be a relationship between Analects 3.5 and the pericopes that make up the rest of chapter 3.

I have only met Hans Zell in person once. However I have repeatedly benefited from his scholarship on African publishing. I have observed deep acts of generosity to African scholarship in Africa. Therefore it is an honour and delight to be asked by the editors to write an appreciation of Hans.

This study explores the leadership dynamics, conflict, and group cohesion during Roald Amundsen’s South Pole expedition, with a particular focus on the critical confrontation between Amundsen and Hjalmar Johansen. Through a dual-method approach that integrates Narrative and Thematic Analysis, the research delves into the diaries and autobiographical writings of key expedition members. The findings reveal that while Amundsen’s authoritative leadership was pivotal to the expedition’s success, it also fostered significant internal conflict, particularly with Johansen. This tension highlights the delicate balance between decisive leadership and the need for inclusiveness in high-stakes environments. The study provides a nuanced understanding of how varying levels of loyalty among team members influenced group dynamics, offering insights that extend beyond the historical context of polar exploration to contemporary leadership challenges in extreme conditions.