Coherent Synthesis Research Articles

Generation of Bessel-Gaussian vortex beam by combining technology

Bessel beam is an important member of the family of non-diffracting beams and has some unique properties which can be used in many areas, such as micro particle manipulating, material processing and optical communication. However, the source of Bessel beam generated by the existing methods can be used only in a short distance due to its low power. In this paper, according to the coherent combining technology, we propose a method to generate a second-order Bessel-Gaussian (BG) beam by loading discrete vortex phase on specific spatially distributed Gaussian beam array. The coherent combining technology can enhance the output power by increasing the number of beams and use the phase-locking technique to maintain the beam quality. The experimental scheme is described as follows. The expanded Gaussian beam is first split by an amplitude-based spatial light modulator, then the Gaussian beam array is incident on a phase-only spatial light modulator to load the discrete vortex phase, and finally the Gaussian beam array loaded with phase can synthesize BG beam in free space. Due to the diffraction effect of the sub-beams, the optical field distribution between the adjacent sub-beams which are loaded with phase differences, are superimposed. As a result, the optical field distribution of the approximate beam can be obtained by coherent synthesis in free space. After that, the degree of similarity between simulated results and theoretical data is analyzed by correlation coefficient, including the comparison of light intensity between experiment and simulation, and the power-in-the-bucket is used to evaluate beam quality. In addition, the topological charge of the synthesized BG beams is verified by the interference method. By studying the number of beams, the waist radius and the radius of the ring, we find some interesting results which are summarized as follows. Firstly, the closed arrangement of Gaussian beam arrays can improve the quality of the synthesized BG beam. Secondly, the smaller the phase difference between the sub-beams, the more easily the discontinuous piston phase approaches to the vortex phase. Therefore, increasing the number of sub-beams can significantly improve the beam quality of the synthesized BG beam and obtain a higher order synthetic BG beam. Finally, we define the parameter k to represent the tightness of a circular array of Gaussian beams. The present study shows that when the parameter k is close to 1, the best experimental results can be obtained. Therefore, the proposed method has important guidance in generating various vortex beams or enhancing the vortex beam power.

线阵光纤激光相干合成角度扫描控制方法研究

Laser beam combining technique allows increasing the power of laser radiance far beyond what is obtained from a single conventional laser. Moreover, this technique is also able to control the far-field laser combining intensity distribution. Based on the theory, the principle of coherent combining of lasers from multi-core linear fiber array was studied. By using the coherent synthesis model, the coherent combining effect of multi-core linear fiber array was numerically simulated by MATLAB when wavefront of the lasers with and without random phase noise respectively, and the feasibility of angle scanning using actively phase-controlling was analyzed. The coherent combining angle scanning control system was built based on MOPA laser linear array fibers. The experiment shows that active phase-controlling of the laser linear array is able to realize the angle scanning of the main maximal stripe, and the scanning range is between two secondary large stripes. The experimental results are consistent with the theoretical calculation, and that has a guiding significance to the application of coherent combining of linear fiber array lasers.

INNOVATION PROJECT MACHINE IN A SYSTEMS APPROACH TO ENGINEERING MANAGEMENT

: In recent years, the project approach has become an increasingly popular tool for achieving operational and strategic goals and to generally advance the business activity of organizations in fields such as innovation management. We demonstrate the need of including the project approach in the processes of creating innovative solutions. We posit that these two work methods can be combined into a coherent approach known as the innovation project machine. As part of this approach, innovations are implemented and developed more effectively, while agile project management and consolidated research for project managers, amongst others, are the source of inspiration. A systems approach to this concept could constitute a coherent synthesis of solutions available for engineering management. A proposition to integrate the project approach with innovative processes will enable expedient execution of business strategies in contemporary companies.

Quantum linear coherent controller synthesis: A linear fractional representation approach

This paper is concerned with a linear fractional representation approach to the synthesis of linear coherent quantum controllers for a given linear quantum plant. The plant and controller represent open quantum harmonic oscillators and are modelled by linear quantum stochastic differential equations. The feedback interconnections between the plant and the controller are assumed to be established through quantum bosonic fields. In this framework, conditions for the stabilization of a given linear quantum plant via linear coherent quantum feedback are addressed using a stable factorization approach. The class of all stabilizing quantum controllers is parameterized in the frequency domain. Coherent quantum weighted ℋ2 and ℋ∞ control problems for linear quantum systems are formulated in the frequency domain. Finally, a projected gradient descent scheme is outlined for the coherent quantum weighted ℋ2 control problem.

Coherent synthesis of genomic associations with phenotypes and home environments.

Local adaptation is often studied via (i) multiple common garden experiments comparing performance of genotypes in different environments and (ii) sequencing genotypes from multiple locations and characterizing geographic patterns in allele frequency. Both approaches aim to characterize the same pattern (local adaptation), yet the complementary information from each has not yet been coherently integrated. Here, we develop a genome-wide association model of genotype interactions with continuous environmental gradients (G×E), that is reaction norms. We present an approach to impute relative fitness, allowing us to coherently synthesize evidence from common garden and genome-environment associations. Our approach identifies loci exhibiting environmental clines where alleles are associated with higher fitness in home environments. Simulations show our approach can increase power to detect loci causing local adaptation. In a case study on Arabidopsis thaliana, most identified SNPs exhibited home allele advantage and fitness trade-offs along climate gradients, suggesting selective gradients can maintain allelic clines. SNPs exhibiting G×E associations with fitness were enriched in genic regions, putative partial selective sweeps and associations with an adaptive phenotype (flowering time plasticity). We discuss extensions for situations where only adaptive phenotypes other than fitness are available. Many types of data may point towards the loci underlying G×E and local adaptation; coherent models of diverse data provide a principled basis for synthesis.

Wilhelm His and mechanistic approaches to development at the time of Entwicklungsmechanik.

At the end of the nineteenth century, approaches from experimental physiology made inroads into embryological research. A new generation of embryologists felt urged to study the mechanisms of organ formation. This new program, most prominently defended by Wilhelm Roux (1850-1924), was called Entwicklungsmechanik. Named variously as "causal embryology", "physiological embryology" or "developmental mechanics", it catalyzed the movement of embryology from a descriptive science to one exploring causal mechanisms. This article examines the specific scientific and epistemological meaning of the mechanistic approaches of embryological development by focusing on Wilhelm His' (1831-1904) histogenetic work. Roux was neither the first, nor the only one to argue for an experimental exploration of causes in embryology. At the time of Roux, physiological explanations of the genesis of the anatomical forms were developing in parallel, not only in German-speaking countries, but in France, Switzerland and English-speaking countries as well. The experimental approach and the cellular descriptions of embryogenesis were already omni-present when Roux proposed his Entwicklungsmechanik. However, these approaches remained disjointed. It appears that it was Wilhelm His who first succeeded in combining the question of the causal factors determining epigenesis, which was closely connected with experimentation on, and cellular descriptions of, development, in a coherent and concrete synthesis, making him one of the true initiators of the developmental mechanics.

Awakening, Efficacy, and Action: A Qualitative Inquiry of a Social Justice‐Infused, Science Education Program

AbstractThis article describes an innovative application of a social justice‐infused pedagogy to an out‐of‐school program for urban high school students. Using an interdisciplinary framework, the program featured a coherent synthesis of science, technology, engineering, and math (STEM) education, highlighting environmental and food justice perspectives; social justice education; and career and college planning. We used qualitative content analysis to analyze two separate interviews with six female and three male students of color ranging in age from 15 to 18 with an average age of 16.1 (SD=1.26) across an approximately 10‐month time span. Utilizing a model of critical consciousness development as our organizing framework, we explored the students’ understanding of environmental and food justice issues. Participants indicated that they were actively engaged in learning about food and environmental justice, exploring STEM careers, and investigating the various ways that social justice is manifested in their lives. Implications for social justice and STEM education interventions as well as broader public policies are discussed.

Rebuilding the Chinese Soul: Some Considerations for Education.

This paper tackles the issue of education as the process of person-making and attempts to redefine the ideal and unique Chinese person—the Chinese soul—based on a civilizational dialogue and synthesis that would transform modern education and enable education to play a central role in “redeeming modernity” and revitalizing Chinese civilization. The paper briefly analyzes the historical efforts, and failures, to reform the Chinese soul and argues that the 150-year effort to revitalize Chinese culture and transform the Chinese people by way of adopting certain aspects of Western civilization has mostly failed because a sufficiently coherent and meaningful synthesis of the two civilizations was lacking.

Coherent multi-layer landscape synthesis

We present an efficient method for generating coherent multi-layer landscapes. We use a dictionary built from exemplars to synthesize high-resolution fully featured terrains from input low-resolution elevation data. Our example-based method consists in analyzing real-world terrain examples and learning the procedural rules directly from these inputs. We take into account not only the elevation of the terrain, but also additional layers such as the slope, orientation, drainage area, the density and distribution of vegetation, and the soil type. By increasing the variety of terrain exemplars, our method allows the user to synthesize and control different types of landscapes and biomes, such as temperate or rain forests, arid deserts and mountains.

Digital phase correction of a partially coherent sparse aperture system.

A digital piston phase correction method is presented for partially coherent synthesis with active or passive illumination. An anamorphic pupil relay causes a linear shift of a two subaperture array between the entrance and exit pupils. This shift separates the subapertures' cross- and auto-correlations while retaining their common spatial frequency information. Digital analysis of these common frequencies finds the separation distance and piston phase error of the cross-correlations and enables lossless correction of phase error. Corrected images are diffraction limited. Partial coherence affects the contrast of each spatial frequency, causing optical path difference tolerances to relax as system bandwidth decreases.

Study on coherent coupling of multi-core PCFs

In this work, we used R-Soft software to simulate the coupling between multi-core photonic crystal fibers (PCFs) with different core diameters and distances. The simulation results show that the core distance within two wavelengths, different core diameters between the mode fields can be effectively coupled. The results are consistent with the evanescent wave propagation length of calculation. According to the designed structure based on the high temperature melting method, the multi-core PCF can be obtained by using two times technique of the optical fiber drawing tower. The core production of (2-, 7-, 19-core PCF) of coherent synthesis experiment, observed apparent interference fringes in the experiment, which shows that the mode fields of the multiple cores meet the coherent conditions. This article provides a theoretical basis and guidance to effectively achieve a coherent coupling for the further design and preparation of multi-core fibers (more than 19 cores).

Kenneth Waltz is not a neorealist (and why that matters)

Faced with scepticism about the status of grand theory in International Relations, scholars are re-evaluating Kenneth Waltz’s contribution to theoretical debates in the field. Readers of Waltz have variously recast his work as structural functionalist, scientific realist and classical realist in liberal clothing. We contribute to this re-evaluation by systematically assembling misreadings of Waltz that continue to occur across all of International Relations’ schools — that his theory is positivist, rationalist and materialist — and offering a coherent synthesis of his main contributions to International Relations theory. By linking Theory of International Politics to both Man, the State, and War and Waltz’s post-1979 clarifications, we show that Waltz offers International Relations scholars a coherent vision of the worth and method of grand theory construction that is uniquely ‘international’. In particular, we focus on Waltz’s methodology of theory building and use of images, demonstrating these to be underappreciated but crucially important aspects of Waltz’s work. We finish by proposing methodological, practical and pedagogical ‘takeaways’ for International Relations scholars that emerge from our analysis.

Coherent perfect absorption and transmission of a generalized three-mode cavity optico-mechanical system

With the rapid development of nano-physics and quantum optics, optico-mechanical coupling system is developing toward the miniaturization and lightweight. The physical characteristics of optical cavity and applications of optic-mechanical devices have received much attention. In this paper, a generalized three-mode cavity optico-mechanical system is presented, the steady-state responses of the system to the characteristics of weak detection of light absorption and dispersion in several different coherent driving modes are studied. Situated in the middle of system is a portable total reflection mechanical oscillator with a reflectance of 100%, and located on each side is a fixed optical cavity mirror with partial transmittance, Three-mode cavity optical mechanical system consists of fixed-mirror, removable-vibrator, fixed-mirror structure. in which the two optical cavities are coupled by coupling a stronger control field and weak probe light with the same mechanical oscillator. Analysis and numerical results show that under the mechanism with different parameters, due to nonlinear effect of pressure, in the three-mode cavity optical mechanical system, there appear some interesting quantum coherent phenomena such as coherent perfect absorption, coherent perfect transmission and coherent perfect synthesis. When coherent perfect absorption occurs, the mutual conversion between input signal power full-field energies and oscillator vibration of internal coherence can be realized, and the law of conservation of energy is satisfied. When relaxation rate due to mechanical oscillator is very small, the coherent perfect transmission is completely transmitted from the system side of the input field to the other side in the case of no loss of energy. And mechanical relaxation rate of the oscillator approaches to zero in the middle, which can ensure that the perfect transmission of the detection field takes place on one side, and the field total reflection and coherent perfect synthesis happen on the other side of. In addition, we alsofind that the adjustment of coupling between cavity and cavity can change the intensity of the probe field of quantum coherent control thereby realizing that the output of the detection field is transformed between coherent perfect absorption and coherence transmission; through simple phase modulation the output direction and input direction of detection field for left cavity-right cavity can swap mutually. So, these dynamic controls in quantum information networks can be used to construct some optical devices with special functions, such as photon switch, photo router, photon exchange machine, etc.

The Practices of the Enlightenment: Aesthetics, Authorship, and the Public by Dorothea E. von Mücke

Reviewed by: The Practices of the Enlightenment: Aesthetics, Authorship, and the Public by Dorothea E. von Mücke Kirk Wetters Dorothea E. von Mücke, The Practices of the Enlightenment: Aesthetics, Authorship, and the Public (New York: Columbia University Press, 2015). Pp. 320. $75.00. As indicated by its title and subtitle, Dorothea E. von Mücke's study stakes out fields and subfields that are at once vast and specific. While the three trends named in the subtitle invoke established research areas, each of which has been the subject of countless monographs, the main title seeks to grasp these topics in the context of the more sweeping but still well-established terms of "enlightenment" and "practice," with the latter serving as a counterweight to definitions or self-definitions of the Enlightenment through its "ideas." Von Mücke seeks to provide both a supplement and an antidote to studies that look at the history of ideas in a relative vacuum, showing how, well before Kant, new forms of subjectivity were gaining recognition and taking root in religious spiritual exercises that tended toward their own secularization in systematic practices of attentiveness. The coherent synthesis of so many moving parts gives The Practices of the Enlightenment a breathtaking scope. This ambitiousness is worth emphasizing because it is easy to overlook given the no-nonsense, unpretentious erudition and slightly understated style of first-person singular scholarship with which von Mücke concisely traverses numerous canonical and noncanonical authors and potentially contentious topics regarding the legacy of the Enlightenment. Although the main focus is on German-language authors (Herder, Lessing, and Goethe as well as lesser-known figures such as Johann Arndt, Johanna Eleonora Petersen, Thomas Abbt, and Friedrich Carol von Moser), von Mücke's inclusion of extensive sections on Rousseau shows the international and comparative scope of the topics under consideration. A key virtue of this study is its ability to bring German-language scholarship of the eighteenth century into dialogue with internationally recognized theoretical paradigms. The reader should not, however, expect extensive direct analysis of these paradigms (e.g., Habermas's critical public sphere, Benedict [End Page 129] Anderson's imagined communities), which serve primarily to define the inherited framework of scholarly discourse. Such positions are the springboards that energize more granular investigations and critical rereadings of studies in more specialized areas such as German Pietism. This relative particularity of the individual analyses should not be allowed to obscure the fact that von Mücke's overall goal is a fundamental revision of our collective view of the Enlightenment. To pinpoint this, I would connect all three sections of the study to her central conceptualization of "disinterested interest"—which is derived not from Kant but from much more exoteric (often religious) sources. In part 1, "The Birth of Aesthetics, the Ends of Teleology, and the Rise of Genius," von Mücke shows how modern aesthetic perception was an outcome of Pietist contemplative interiority and attentiveness, which correlate with distance from the world and its institutions. Part 2, "Confessional Discourse, Autobiography, and Authorship," shows how modern authorship in the emphatic sense in the cases of Rousseau and Goethe was derived not from the mirroring of author and audience but from the experience of rupture between the two. Finally, part 3, "Imagined Communities and the Mobilization of a Critical Public," explores the possibilities of different kinds of publics setting aside their own self-interest in favor of the common good. Von Mücke traces a movement away from identificatory and nationalist potentials (represented by Abbt), toward a community (following Herder, Kant, and Lessing) of extra-institutional participants in a public sphere that transcends the hierarchies and authority structures of church, state, and educational institutions. In her conclusion, von Mücke speaks of "audiences and publics … made up out of atomistic individuals," whose primary "communal bond" lies no longer in religion but in "the domain of art" (242). With respect to the wider contemporary relevance of von Mücke's findings, I would point to the overall sympathy with which she presents these various "practices of the Enlightenment." I do not mean this as a criticism, but as a way of calling attention to...

Long-term stable coherent beam combination of independent femtosecond Yb-fiber lasers.

We demonstrate coherent beam combination between independent femtosecond Yb-fiber lasers by using the active phase locking of relative pulse timing and the carrier envelope phase based on a balanced optical cross-correlator and extracavity acoustic optical frequency shifter, respectively. The broadband quantum noise of femtosecond fiber lasers is suppressed via precise cavity dispersion control, instead of complicated high-bandwidth phase-locked loop design. Because of reduced quantum noise and a simplified phase-locked loop, stable phase locking that lasts for 1 hour has been obtained, as verified via both spectral interferometry and far-field beam interferometry. The approach can be applied to coherent pulse synthesis, as well as to remote frequency comb connection, allowing a practical all-fiber configuration.

The Utility of Post-Conviction Polygraph Testing Among Sexual Offenders.

It is often difficult to ascertain the true extent and nature of sexually deviant behavior, as much relies on self-report or historic information. The polygraph has been proposed as a useful tool in the treatment and supervision of sex offenders. The current review aims to provide a coherent, objective, and recent synthesis of evaluation studies exploring the utility of the post-conviction polygraph (PCSOT) in the treatment and management of sexual offenders. This was assessed based on offense recidivism rates and disclosure; self-reported utility was also considered. Nineteen studies were identified from the United States, the United Kingdom, and the Netherlands with no randomized controlled trials identified. Overall, there was a significant increase in relevant disclosures associated with the polygraph. The impact on reoffending rates was significant for violent but not sexual offenses. A number of methodological factors introduced the potential for bias in a significant number of studies reviewed in this review.

What evidence exists for the effectiveness of on-farm conservation land management strategies for preserving ecosystem services in developing countries? A systematic map

AbstractBackgroundAn extensive body of evidence in the field of agro-ecology claims to show the positive effects that maintenance of ecosystem services can have on meeting future food demand by making farms more sustainable, productive and resilient, which then contributes to improved nutrition and livelihoods of farmers. However, inconsistent effects have commonly been reported, while empirical evidence to support assumed improvements is largely lacking. Overall, a coherent synthesis and review of the evidence of these claims is largely absent from the literature.MethodsSystematic searches of peer-reviewed research were conducted in bibliographic databases of Web of Science, SCOPUS, AGRICOLA, AGRIS databases and CAB abstracts, and grey literature from Google Scholar, and 32 subject-specific websites. Searches identified 21,147 articles. After screening, 746 studies were included in the final map.ResultsOf the 19 conservation land management practices considered, soil fertilisation (24 %), tillage (23 %), agroforestry (9 %), and water conservation (7 %) were most commonly studied. Ecosystem services most commonly studied were supporting (55 %) and regulating (33 %), particularly carbon sequestration/storage, nutrient cycling and soil/water regulation/supply. Key data gaps identified included the absence of long-term records (with datasets spanning >20 years), studies located in North and Central Africa, research that focuses on smallholder landscapes, and studies that span different scales (regional and landscape levels).ConclusionsThe study employs systematic mapping combined with an online interactive platform that geographically maps results, which allows users to interrogate different aspects of the evidence through a defined database field structure. While studies are not directly comparable, the database of 746 studies brings together a previously fragmented and multidisciplinary literature base, and collectively provides evidence concerning a wide range of conservation land management practices impacting key ecosystem services. The systematic map is easily updatable, and may be extended for additional coding, analysed to assess the quality of studies, or used to inform future systematic reviews.

From God’s Chinese names to a cross-cultural universal God: James Legge’s intertextual theology in his translation of Tian, Di and Shangdi

ABSTRACTOften referred to as a Victorian sinologist, James Legge has received much critical discussion in the discipline of Chinese studies. Yet few scholars have probed his role as a translator and the transmission of his theological ideas by examining his oeuvre. This article adopts the theoretical concepts of intertextuality and intertextual coherence to investigate Legge’s translation of Tian 天, Di 帝 and Shangdi 上帝, the three key terms that, in his view, convey the ancient Chinese notions of a supreme God. Drawing on Legge’s annotated Chinese Classics and various other works on religious issues in ancient and dynastic China, the article looks at how he establishes an intertextual theology through a coherent synthesis of Ruist (Confucian) hermeneutics and Christian (Congregational Protestant) argumentation. Ultimately, Legge’s vision of a universal God as known in the histories of China and the West reveals his work’s far-reaching implications for contemporary cross-cultural communication.

Clarifying concepts and categories of assumptions for use in evaluation

In order to advance systematic examination of how evaluators work with assumptions, there is need for; first of all, a coherent synthesis and categorization of assumptions, as well as a discussion of their varied relevance in program design and evaluation. An emergent typology of assumptions as they are used in the literature will be proposed based on categories of assumptions as used in literature. The critical role and potential contribution of the articulation of paradigmatic, normative, diagnostic, prescriptive, causal, external and other assumptions in program design and evaluation are discussed and then evaluated for utility to current evaluative practice.

Incoherent signal source resolution based on coherent aperture synthesis

A technique is proposed for resolving two incoherent signal sources of the same frequency and significantly different intensities with similar angular coordinates. The technique is based on aperture synthesis of a receiving array, first, by the signal of higher-power source and the estimate of its angular coordinate with subsequent subtraction of the signal spectrum from the angular spectrum of the received field. This makes it possible to achieve aperture synthesis and estimate the angle of arrival of a higher-power signal. Thus, the technique is of interest not only for synthesized apertures, but also for arrays with a filled aperture, since it eliminates the restrictions imposed by the presence of lateral lobes of the array response. Our mathematical simulation data demonstrate the efficiency of this technique in the detection and location of weak signals against the background of high-power noise sources even at their close angular positions.