Excessive Dispersion Research Articles

Knapsack Balancing via Multiobjectivization

In this paper, we address the aspect of knapsack balancing in the classic knapsack problem. Recognizing that excessive dispersion in the objective function or constraint coefficients of the optimal solution can be undesirable, we propose, when appropriate, to control this effect through problem multiobjectivization. By multiobjectivization, we mean the addition of one or more objective functions that aim to shift the original problem’s optimal solutions towards Pareto optimal solutions of the multiobjectivized problem, reducing the dispersion of the respective coefficients. We detail how the knapsack balance aspect can be incorporated into the standard knapsack problem model and demonstrate the functionality of this enriched model through illustrative examples.

Coating effect of polyurethane-layered double hydroxide nanocomposite on steel

The motivation behind this work is the preparation of polyurethane-magnesium aluminum layered double hydroxide (PU-LDH) nanocomposite and its application as a coating for steel protection. The coating was prepared with different doses of LDH, ranging from 0 to 2% of the coating weight. The effect of different concentrations on the mechanical, adhesion, and surface properties of PU coating is studied. Firstly, LDH was prepared via the coprecipitation process and then distributed in PU matrix. The nanocomposites were then crosslinked in the form of coating layers on steel. The preparation of the thermally stable crystalline LDH nanoparticles with 89 nm particle size was confirmed by FTIR, XRD, DLS, and TGA. SEM photos showed the dispersed and intercalated structure. The coating characteristics demonstrate that addition of LDH decreased the drying time and increased the dry film thickness of PU up to 1.5% due to the crosslinking between the large surface area nanofiller and polyurethane matrix. Furthermore, the prepared LDH nanofiller increased the adhesion strength, impact resistance, abrasion resistance, modulus, and flexibility of PU due to the strong polymeric network structure. The 2% nanocomposite coating shows poor properties due to the excess concentration and heterogeneous dispersion of nanoparticles within the PU polymer. The resistance to fire and some chemicals was supported by the thermally and physically stable LDH nanoclay. The former characterizations state that the proposed PU-LDH nanocomposite is an enhanced and applicable coating.

A numerical investigation on the effects of passenger movement on droplet dispersion in a high-speed train compartment

Cough droplets pose significant risks to human respiratory health, potentially leading to severe infections in indoor environments. In the confined and densely populated high-speed train compartment, passenger movement is unavoidable and follows a fixed path. This movement impacts the designed airflow and, consequently, influences the dispersion of cough droplets. In this study, a validated computational fluid dynamics overset mesh method was adopted to implement passenger movement along the aisle, and the impact of passenger movement on droplet dispersion inside a high-speed train compartment was investigated. The results show that the wake flow generated by moving passengers can carry cough droplets along the direction of movement. The timing and speed of passenger movement play a pivotal role in the extent of droplet dispersion. Premature and delayed interactions with the droplet cloud diminish engagement due to inadequate and excessive dispersion, respectively. When a passenger begins walking at the 10th second, droplet transfer in the direction of movement peaks, reaching up to 4.9 times that of the stationary case in the area of seat 13A, with droplet transmissions extending up to 6 m. The walking speed affects the intensity of the wake flow. A walking speed of 1.0 m/s or higher results in the noticeable transmission of droplets in the direction of the walking passenger. These findings underscore the necessity for incorporating human movement dynamic in the development of ventilation strategies and public health guidelines to mitigate airborne transmission risks in enclosed public spaces.

Optimization of Growth Response Parameters, Screening and Molecular Detection of Pesticide Degradation Genes in Bacterial Isolates from Agricultural Soils

Study’s Novelty/ Excerpt This study demonstrated the capability of bacteria isolated from farmland soils in Kano Metropolis to biodegrade dichlorvos and carbofuran pesticides, identifying Bacillus sp., Serratia sp., and Pseudomonas sp. as key degraders. Optimization experiments revealed that Serratia sp. thrived at 100 mg/L dichlorvos concentration and 35°C, while Pseudomonas sp. showed maximum growth at 300 mg/L carbofuran concentration and 30°C, both with a pH of 7.0, 100 rpm agitation, and 5-day incubation period. Molecular analysis confirmed the presence of opd and mcd genes in Serratia sp. and Pseudomonas sp., respectively, highlighting their potential for effective bioremediation of pesticide-contaminated soils. Full Abstract Pesticides are organic compounds synthesized and used for pest control. The excessive and continuous dispersion of pesticides in the environment results in environmental pollution, necessitating remediation. This study investigated the potential of bacteria isolated from farmland soils in Kano Metropolis, Kano State, Nigeria, with a history of dichlorvos (2,2-dichlorovinyldimethylphosphate) and carbofuran (2,3-dihydro-2,2-dimethyl-7-benzofuranyl methylcarbamate) application, to biodegrade these pesticides. Three sampling sites were involved in sample collection, and the soil physicochemical parameters from each sample were determined. Isolation, identification, and screening of the bacterial isolates capable of utilizing the pesticides as sole sources of carbon were carried out. The following parameters (concentration of the pesticides, pH, temperature, agitation, and incubation time) were optimized to maximize degradation. The potent bacterial isolates were further subjected to molecular analysis for the detection of opd and mcd genes. The pesticide-degrading bacteria were identified as Bacillus sp., Serratia sp., and Pseudomonas sp. Serratia sp. recorded the highest growth in the presence of 1% v/v dichlorvos, while Pseudomonas sp. exhibited maximum growth at a 1% w/v carbofuran concentration. The optimized conditions that yielded the maximum microbial growth are: 100 mg/L pesticide concentration for Serratia sp and 300 mg/L for Pseudomonas sp, a pH of 7.0 and an agitation level of 100 rpm for both organisms, a temperature of 35°C for Serratia sp and 30°C for Pseudomonas sp, and an incubation time of 5 days for both organisms. The opd and mcd genes were identified from Serratia sp. and Pseudomonas sp. respectively. These results suggest that the isolated bacteria have the potential to degrade dichlorvos and carbofuran pesticides from the contaminated soil

Carbon Nanotube Films with Fewer Impurities and Higher Conductivity from Aqueously Mono-Dispersed Solution via Two-Step Filtration for Electric Heating.

With the intensification of global climate problems, electric heating has recently attracted much attention as a clean and low-carbon heating method. Carbon nanotubes (CNTs) are an ideal medium for electric heating applications due to their excellent mechanical, electrical, and thermal properties. The preparation of electrothermal films based on an aqueous CNT dispersion as a raw material is environmentally friendly. However, in the traditional one-step filtration method, the residual excess dispersant and the small aspect ratio of the CNTs in the preparation process limit the performance of electrothermal CNT films. In this paper, we report a two-step filtration method that removes the free dispersant and small CNTs in the first filtration step and obtains denser CNT films by controlling the pores of the filter membrane in the second filtration step. The results suggest that, compared to the CNT1 film obtained from one-step filtration, the CNT1-0.22 film, obtained from two-step filtration using 1 and 0.22 μm membranes, has a smoother and flatter surface, and the surface resistance is 80.0 Ω sq-1, which is 29.4% lower. The convective radiation conversion efficiency of the CNT1-0.22 film is 3.36 mW/°C, which is 36.1% lower. We anticipate that such CNT films could be widely applied in building thermal insulation and underfloor heating.

Combinatorial Quantification of Multi-Features of Coda Waves in Temperature-Affected Concrete Beams.

Coda waves are highly sensitive to changes in medium properties and can serve as a tool for structural health monitoring (SHM). However, high sensitivity also makes them susceptible to noise, leading to excessive dispersion of monitoring results. In this paper, a coda wave multi-feature extraction method is proposed, in which three parameters, the time shift, the time stretch, and the amplitude variation of the wave trains within the time window, are totally derived. These three parameters are each mapped to the temperature variations of concrete beams, and then combined together with their optimal weight coefficients to give a best-fitted temperature-multi-parameter relationship that has the smallest errors. Coda wave signals were collected from an ultrasonic experiment on concrete beams within an environmental temperature range of 14 °C~21 °C to verify the effectiveness of the proposed method. The results indicate that the combination of multi-features derived from coda wave signals to quantify the medium temperature is feasible. Compared to the relationship established by a single parameter, the goodness-of-fit is improved. During identification, the method effectively reduces the dispersion of identification errors and mitigates the impact of noise interference on structural state assessment. Both the identification accuracy and stability are improved by more than 50%, and the order of magnitude of the identification accuracy is improved from 1 °C to 0.1 °C.

Cooling and optimizing urban heat island based on a thermal knowledge-informed multi-type ant colony model

In the context of rapid urbanization and global warming, the urban heat island (UHI) intensifies the risk of heat-related mortality, endangering the health of urban residents. Urban greening effectively mitigates severe urban heating climates, but increasing green space without restrictions is undesirable due to the scarcity of urban land. Accurately characterizing the scope and intensity of UHI and determining the spatial location of the area that needs to be optimized are necessary. In this study, an inverse S-shaped function was used to fit the urban-rural temperature attenuation, whose parameters explicitly describe the properties of UHI. Additionally, a thermal knowledge-informed multi-type ant colony model was proposed to cool UHI automatically. A case study of Wuhan showed that: (1) the fitting effect of the inverse S-shaped function is desirable with the adjusted R2 exceeding 0.97, and the derived parameters with clear physical meanings avoid subjectivity in describing thermal characteristics; (2) high-level heat island of the main urban areas can be reduced by 7.7%–8.5% after land use optimization; and (3) a comparison with the traditional multi-type ant colony model verifies that the model proposed in this study can avoid excessive dispersion of the optimized pixels whose land use types are modified and achieve more reasonable and stable optimization results. This study provides useful exploratory tools for sustainable urban planning, heat mitigation solutions, and other urban retrofitting.

ScCRT: a contrastive-based dimensionality reduction model for scRNA-seq trajectory inference.

Trajectory inference is a crucial task in single-cell RNA-sequencing downstream analysis, which can reveal the dynamic processes of biological development, including cell differentiation. Dimensionality reduction is an important step in the trajectory inference process. However, most existing trajectory methods rely on cell features derived from traditional dimensionality reduction methods, such as principal component analysis and uniform manifold approximation and projection. These methods are not specifically designed for trajectory inference and fail to fully leverage prior information from upstream analysis, limiting their performance. Here, we introduce scCRT, a novel dimensionality reduction model for trajectory inference. In order to utilize prior information to learn accurate cells representation, scCRT integrates two feature learning components: a cell-level pairwise module and a cluster-level contrastive module. The cell-level module focuses on learning accurate cell representations in a reduced-dimensionality space while maintaining the cell-cell positional relationships in the original space. The cluster-level contrastive module uses prior cell state information to aggregate similar cells, preventing excessive dispersion in the low-dimensional space. Experimental findings from 54 real and 81 synthetic datasets, totaling 135 datasets, highlighted the superior performance of scCRT compared with commonly used trajectory inference methods. Additionally, an ablation study revealed that both cell-level and cluster-level modules enhance the model's ability to learn accurate cell features, facilitating cell lineage inference. The source code of scCRT is available at https://github.com/yuchen21-web/scCRT-for-scRNA-seq.

МЕТОДИКА ИНТЕГРАЦИИ ПРОИЗВОДСТВЕННО-ТЕХНИЧЕСКИХ БАЗ ОБСЛУЖИВАНИЯ И РЕМОНТА ВЕДОМСТВЕННЫХ АВТОМОБИЛЕЙ

The relevance of this study lies in the fact that motor transport services of federal ministries and departments of the Russian Federation, agencies subordinate to them, law enforcement and supervisory authorities are carried out by departmental road transport. The operation of departmental road transport in modern conditions is based on documents developed for public road transport. In some cases, departmental acts on the organization of the work of vehicles and personnel in relation to the functions and tasks of the relevant department are not systematically used. The operation of departmental road transport is characterized by excessive dispersion of regional production and technical bases for the maintenance, maintenance and repair of a specialized fleet, as a rule, assigned to individual institutions. As a result, more material and technical resources, rolling stock and personnel are involved in the transportation process of departmental road transport than at public road transport. Increasing the efficiency of departmental road transport consists in the consolidation and centralization of regional production and technical bases, as well as in rationing the resource provision of the transport process. The subject of the study is the regularities of the functioning of the production and technical bases units of the departmental structure. The purpose of this study is to increase the efficiency of departmental road transport operation due to the territorial integration of production and technical bases. To achieve this goal, it is necessary to solve a number of tasks, the specifics of which are determined by the features of a specialized departmental road transport on the example of the divisions of the regional Department of the Federal Penitentiary Service for the Rostov region, concluded: a) in the collection, grouping and processing of statistical information from divisions by type, model, number and costs of operation and performance of transportation in the field of transport by specialized rolling stock; b) determination by geographical coordinates of the location of divisions in the region; c) the compilation of an adjacent matrix of distances between divisions. The methodology of the study includes a methodology for the territorial integration of production and technical bases of regional units of departmental road transport based on the «center of gravity» method, taking into account the costs of operating a specialized fleet and determining the head production and technical bases. The obtained research results can be used for other departments, divisions, organizations and services of departmental structures in which a specialized fleet is involved.

Femtosecond Pulsed Laser Irradiation of Zirconia for Embedding Silver Nanoparticles in Surface Nanopores

Femtosecond pulsed laser irradiation was performed to investigate the feasibility and fundamental characteristics of embedding silver nanoparticles onto zirconia ceramic surfaces. By irradiating laser, nanopores were fabricated on the surface of the yttria-stabilized zirconia (YSZ) substrate, and silver nanoparticles were infiltrated and immobilized into the pores using a commercial nano-silver dispersion solution. Numerous nanopores embedded with silver nanoparticles were successfully obtained on the YSZ surface while keeping the grains’ shapes unchanged by controlling laser parameters. Optimizing laser fluence and scanning speed near the ablation threshold made it possible to remove only the excess dispersant that remained on the surface while keeping silver in the pores and without causing machining of the surface of the YSZ substrate. In addition, about 60% embedding in the nanopores was achieved. It was found that the shorter pulse width was suitable to avoid evaporating both dispersant and silver. Cross-sectional observation revealed that the silver nanoparticles were agglomerated to form clumps and were embedded without a gap at the bottom of the pores at a depth of about 600 nm. After laser irradiation, no significant laser-induced phase change was observed in the YSZ substrate, indicating that there was no in-process thermal damage to the bulk. These findings demonstrated the possibility of adding a metal nanoparticle to the zirconia surface by using only a laser process without damaging the properties of the base material during the process. New applications of zirconia, such as the generation of functional surfaces with antibacterial properties, are expected.

Searching for the Sources of Excess Extragalactic Dispersion of FRBs

Abstract The FLIMFLAM survey is collecting spectroscopic data of field galaxies near fast radio burst (FRB) sight lines to constrain key parameters describing the distribution of matter in the Universe. In this work, we leverage the survey data to determine the source of the excess extragalactic dispersion measure (DM), compared to Macquart relation estimates of four FRBs: FRB20190714A, FRB20200906A, FRB20200430A, and FRB20210117A. By modeling the gas distribution around the foreground galaxy halos and galaxy groups of the sight lines, we estimate DMhalos, their contribution to the FRB DMs. The FRB20190714A sight line shows a clear excess of foreground halos which contribute roughly two-thirds of the observed excess DM, thus implying a sight line that is baryon dense. FRB20200906A shows a smaller but nonnegligible foreground halo contribution, and further analysis of the intergalactic medium is necessary to ascertain the true cosmic contribution to its DM. FRB20200430A and FRB20210117A show negligible foreground contributions, implying a large host galaxy excess and/or progenitor environment excess.

Effects of dry powder mixing on electrochemical performance of lithium-ion battery electrode using solvent-free dry forming process

This research examines how the morphology of the electrode powder mixture affects the structure and battery performance of lithium-ion battery electrodes fabricated using a dry electrode forming process. We demonstrate that the distribution of conductive and binding additives (CBA) on the active materials (AMs) can be controlled by adjusting the rotation speed of a dry mixer. Furthermore, we show that controlling the distribution of CBA can improve the rate performance of the batteries. The tortuosity of the CBA domain in the electrodes is analyzed from SEM images of electrode cross-sections as electronic and ionic conductive pathways. Low rotation speed dry mixing results in poor dispersion of CBA, leading to the formation of long-range conductive pathways with low tortuosity. Consequently, the capacity at high rates decreases due to fewer short-range conductive pathways between the AM particles. In contrast, high rotation speed dry mixing leads to excessive dispersion of CBA, resulting in high tortuosity in both long-range and short-range conductive pathways. As a result, the capacity decreases due to fewer efficient conductive pathways throughout the electrode. We demonstrate that medium rotation speed dry mixing achieves a favorable balance between short-range and long-range conductive pathways, providing high capacity at high rates.

Collaborative and Incremental Learning for Modulation Classification With Heterogeneous Local Dataset in Cognitive IoT

Among 6G high-density connection applications, the cognitive Internet of Things (IoT) is considered to be an effective means to cope with the problem of spectrum resource shortage and reduce energy consumption. The modulation classification with the functions of primary user detection and signal recognition has become the core technology in the cognitive IoT. However, the remarkable surge in the generated data makes it intractable to store and analyze such a large amount of data in a centralized manner. Meanwhile, due to the heterogeneity of IoT devices, the collected data in distributed devices may be non-independent-identical distribution, resulting in heterogeneous local datasets problem. Therefore, we introduce the federated learning (FL) and propose federated incremental learning (FIL) method to address the problem of heterogeneous local datasets in modulation classification. Specifically, we regard the private classes of a particular local device as incremental classes and incremental learning is adopted to learn the classification knowledge of private classes. In order to avoid excessive dispersion between the global model parameters and local model parameters, we utilize knowledge distillation in the local model training stage for imposing similar constrain of parameters on different local models. Simulation results have proven the effectiveness of our proposed method.

Searching for the sources of excess extragalactic dispersion of FRBs

Searching for the sources of excess extragalactic dispersion of FRBs

Early pigment dispersion and raised intraocular pressure after uneventful central-hole implantable collamer lens surgery

Introduction: With ever-increasing cases of myopia worldwide, there has been a quantum jump in the number of refractive procedures. 3 cases who had an uncomplicated implantable collamer lens (ICL) surgery in both eyes, but had a new complication, are presented here. This is not yet described in the literature to the authors' knowledge. Patient and Clinical Findings: 2 weeks after uneventful bilateral ICL surgery, the patients presented with slight blurring of vision in 1 eye only. On examination, there was excessive pigment dispersion in the anterior chamber both in front of and behind the ICL. They also had raised intraocular pressure (IOP) a few days later, possibly due to blockage of the trabecular meshwork by iris pigments. Diagnosis, Intervention, and Outcomes: All the patients were managed conservatively on anti-inflammatory and IOP-lowering eyedrops. The dispersed pigments decreased with normalization of IOP after 2 to 4 weeks of conservative management with no blurring of vision. However, the pupil remained slightly dilated and irregular in all these cases. Conclusions: The excessive pigment dispersion seen after ICL surgery is not commonly encountered after ICL surgery and can be managed conservatively.

Explosive volcanism of Piton des Neiges (Reunion Island) and excess age dispersion in sanidine: Insights into magma chamber processes in a hotspot setting

Explosive eruptions of trachytic to trachyandesitic composition produced thick and widespread pyroclastic deposits during the recent volcanic activity of Piton des Neiges (PdN), the largest volcano of La Réunion Island (France). However, without precise geochronology for these eruptions, the future behavior of the dormant volcano is difficult to assess. New high-resolution single crystal 40Ar/39Ar dates on alkali feldspar, together with petrochemical data on juvenile clasts, indicate that instead of multiple and small eruptions, PdN produced a single large-volume event (“Dalle Soudée” eruption) at 198.8 ± 2.5 kyrs in which its entire crustal plumbing system was reactivated by mafic injections in the silicic reservoir. After 60 kyrs of quiescence, PdN activity resumed with several small silicic eruptions. From a dome-forming trachytic event (Belouve eruption) represented by some of the most recent block-and-ash flow deposits near the present-day summit we report in-situ 238U/230Th disequilibrium dates on pristine zircons. Sanidine and zircon crystalized at ca. 875 °C in the trachytic magma. For this event, the corresponding 238U/230Th isochron age of the zircons overlaps with the youngest 40Ar/39Ar dates on single sanidine crystals and yields an age of 42.7 ± 3.8 kyr. The variability in trace elements of zircon argues for a prolonged crystallization during this phase prior to eruption. Similarly, the 40Ar/39Ar sanidine dates show a significant spread in both eruptions, covering ca. 80 kyrs, uncommon for a method with a predicted low closure temperature. Such a pattern of age distribution argues for the presence of inherited argon in sanidines and for long residence times in the magma reservoir. The recent eruptive history of Piton des Neiges, involving evolved magma compositions, long-living silicic reservoirs and millennia-long quiescence in volcanic activity, suggests that future potentially hazardous eruptions from this volcano cannot be excluded.

Prawne problemy zaspokajania potrzeb mieszkaniowych w związku z zatrudnieniem w stosunku pracy

The article is an analysis of law on housing relations which genetically and functionally ensue from employment relations. The point of referrence is provid by Aricles 16 and 94 point 8 of the legal code, where an enterprise is put under an obligation to show concern that material, welfare and cultural needs of its employees are met. In author’s opinion this general obligation also embraces an obligatory concern about hosuing needs, which has also been specified by numerous unstatutory regulations. Firstly, these are common rights of all employees of state enterprises, under which they are entitled о financial benefits from the so called housing fund of enterprise. These are collective rights enjoyed by all employees. It is only after the housing fund has been divided, with the representative organs of employees participating, that individual rights come about.On the second level of the specification of the general housing committment of an enterprise there are particular regulations related to the selected groups of employees. These numerous regulations differ in respect of their normative rank, the date of enactment, and provide for a number of housing claims of varying contents and legal nature. As a result of meticulous analysis the the author makes a distinction, into three basic types of claims. The first group embraces housing benefits which are incorporated into the employment relations (e.g. free housing allowances). The second one contains the construction, where employment relations only provide for a possibility to require the execution of a housing claim, whereas the exercise of the claim takes place under a separate privity, e.g. lease. The third group comprises claims ensuing from other relations (recognizance or authoritative) than the employment ones, though entered into in connection with the latter while being employed at an enterprise and under the decision of the latter or any other competent subject.At the end of his article the author critically assesses the excessive differentiation and dispersal of legal provisions on housing relations that ensue from employment, and postulates that a separate and uniform act be passed in this respect.

Systematic investigation on the effect of processing procedures on the performance of oil‐resistant thermoplastic vulcanizates based on HNBR/TPEE

AbstractThe unique “sea‐island” phase of thermoplastic vulcanizates (TPVs) dictates an inseparable correlation between micro‐morphology and properties, the studies on the processing procedures in dynamic vulcanization are of great significance for the preparation of TPVs with desirable performance. Herein, a new type of oil‐resistant TPV with superior stretchability, low hardness, and high elasticity has been successfully fabricated based on hydrogenated acrylonitrile butadiene rubber (HNBR) and thermoplastic polyester elastomer (TPEE). The effect of processing procedures on the phase morphology, rubber network strength, mechanical properties, rheological performance, thermal stability, and oil resistance of HNBR/TPEE TPV was systematically investigated. In the masterbatch procedure, the homogeneous dispersion of the cross‐linking agent in the rubber phase contributes to stronger rubber networks and effectively reduces HNBR particle size. TPV prepared by masterbatch procedure exhibits a more comprehensive performance with improved mechanical properties, better rheological performance, enhanced thermal stability and oil resistance. In contrast, excessive dispersion of peroxide in the plastic phase during the pre‐compound procedure is demonstrated to the degradation of TPEE, resulting in large‐sized defective domains, while the deterioration of the rubber network leads to the inferior performance of TPV. This study provides new insights into the selection of the optimal procedure for preparing oil‐resistant TPVs.

An Integrated Approach to Constructing Ecological Security Pattern in an Urbanization and Agricultural Intensification Area in Northeast China

Ecological security pattern (ESP) can bridge the paradox between ecological conservation and socioeconomic development. Although various methods have been applied to establish ESP successfully, improving its scientificity and reliability for regional sustainability are still great challenges. Taking Harbin administrative region as the study area, this paper integrated the merits of the function-oriented method (assessing the importance of ecological services using the InVEST model) and the structure-oriented method (extracting the connectivity of landscapes based on the MSPA model) to improve the identification of ecological sources more scientifically. Night light data were used to modify the natural resistance surface to reveal the real natural and human disturbance for ES loss during species migration and ecological flows. Then, the ESP was established by combining the ecological nodes after extracting and grading the ecological corridors. The results showed that the individual ES performed with a high spatial heterogeneity and was highly correlated with land use patterns. The extremely important and slightly important were the dominant level types in the study area, and the proportion of extremely important declined greatly from 44.78% in 1980 to 30.14% in 2020. Core was the main landscape type with a proportion of 57.13% and mainly distributed in the Lesser Khingan Mountains and Zhangguangcai Mountains. More than 700 ecological corridors were extracted according to the MCR model and the important ecological corridors were selected based on the gravity model, with 86 ecological nodes obtained from the intersection points of ecological corridors. An ESP of “two zones, two barriers, one axis and one belt” was proposed, and relevant protection measures were put out for the sustainable development in the study area. The findings indicated that imposing ESP could form a stable secure frame for social economic development and ecological protection, avoiding irrational land use modes and excessive dispersion of landscapes. This study could provide valuable references for land use planning and the formulation of related ecological protection policies and regional sustainable development strategies.

James–Stein for the leading eigenvector

Recent research identifies and corrects bias, such as excess dispersion, in the leading sample eigenvector of a factor-based covariance matrix estimated from a high-dimension low sample size (HL) data set. We show that eigenvector bias can have a substantial impact on variance-minimizing optimization in the HL regime, while bias in estimated eigenvalues may have little effect. We describe a data-driven eigenvector shrinkage estimator in the HL regime called "James-Stein for eigenvectors" (JSE) and its close relationship with the James-Stein (JS) estimator for a collection of averages. We show, both theoretically and with numerical experiments, that, for certain variance-minimizing problems of practical importance, efforts to correct eigenvalues have little value in comparison to the JSE correction of the leading eigenvector. When certain extra information is present, JSE is a consistent estimator of the leading eigenvector.