Adjacent Cores Research Articles

Experimental investigation of reservoir sediments

This study presents an experimental approach to investigate cohesive reservoir sediments. It is shown, how adjacent sediment cores can be extracted from reservoir beds with a Frahm Sediment Sampler. The cores are subsequently used for detailed investigations in a hydraulic laboratory. In a first step, related cores are identified based on their bulk density profiles. One part of the related cores is used to analyze the sediment properties over depth by means of potential stability parameters. The other part is used to determine the depth-dependent erosion stability in an erosion flume (SETEG-system). In the SETEG-system, a photogrammetric method is applied to measure the erosion rates of pre-defined sediment layers at different exposed shear stresses. Subsequently, the critical shear stress can be derived, which leads to an objective evaluation and allows a systematic approach. Finally, both results are combined to investigate possible correlations between the evaluated depth-dependent stability parameters and the measured erosion stability. The approach is presented on sediment cores from the case study “Kleiner Brombachsee”, a reservoir that is located in Middle Franconia, Germany.

Surface water productivity and sediment transport by Bering Strait throughflow in the Chukchi Shelf (the western Arctic Ocean) during the Holocene

Diverse paleoceanographic proxies from three sediment cores (GC12ex, JPC35, and JPC30) collected from the Chukchi Shelf north of the Bering Strait elucidate the Holocene paleoceanographic changes (surface water productivity and sediment transport) caused by the Bering Strait throughflow from the Bering Sea into the Chukchi Sea. Lithology of three sediment cores identified the same three units. Based on comparison and correlation to adjacent age-dated cores as well as AMS 14C dates of core GC12ex, the boundary between Unit 1 and Unit 2a is dated about 8500 cal. yr BP, and the boundary between Unit 2a and Unit 2b is also dated about 4500 cal. yr BP. Consistent down-core profiles of the geochemical and isotopic properties among the three cores differentiate the paleoceanographic conditions corresponding to lithologic units. Based on the biogenic opal, total organic carbon, and δ13C values, Unit 1 is characterized by low surface water marine productivity under relatively shallow water with weak transport of Bering Strait throughflow. Unit 2a shows a mixture of terrestrial and marine contributions, indicating the onset of increased marine surface water productivity after the main flooding (~11,500 cal. yr BP) of the Bering Strait by the Holocene sea-level rise. Unit 2b exhibits stable and enhanced marine biogenic opal production similar to the present-day oceanographic conditions. Such paleoceanographic changes were confirmed by the clay minerals (smectite, illite, kaolinite, and chlorite) and detrital isotopes (εNd and 87Sr/86Sr). Thus, the Bering Strait throughflow played an important role on surface water productivity and sediment deposition in the Chukchi Shelf in response to Holocene sea-level rise after the opening of the Bering Strait.

A novel biopsy-related parameter derived from location and relationship of positive cores on standard 12-core trans-rectal ultrasound-guided prostate biopsy: a useful parameter for predicting tumor volume compared to number of positive cores

To develop a novel biopsy-related parameter, named overlapping line, defined as the line between the adjacent positive cores on 12-core trans-rectal ultrasound-guided prostate biopsy, and evaluated the value of overlapping line for predicting tumor volume in the final pathologic examination. Among patients with prostate cancer who underwent radical prostatectomy at Boramae Medical Center, 470 patients who underwent standard 12-core trans-rectal ultrasound-guided prostate biopsy were selected for the analysis. The number of overlapping line was determined in each patient, and its effects on tumor volume were evaluated after adjusting for other variables. Median prostate specific antigen level was 9.1ng/mL, and the maximum % cancer in positive cores was 42.8%. Median numbers of positive cores and overlapping lines were three and two, respectively. The pathologic stage was T2 or less, T3a, and T3b or greater in 297 (63.5%), 104 (22.2%), and 67 patients (14.3%), respectively. Median tumor volume in prostatectomy specimen was 3.4mL. In multivariable analysis, the number of overlapping lines (B 0.750, p<0.001) was a significant predictor for tumor volume, in addition to prostate specific antigen level and maximum % cancer in positive cores. In addition, the model with overlapping line showed superior accuracy compared to the model with positive core based adjusted r 2 (0.467 vs. 0.456). The number of overlapping lines, a novel prostate biopsy-related variable, is thought to be a more reliable predictor for tumor volume compared to the number of positive cores and could be easily applied to routine daily practice.

Electromagnetic Design and Analysis of a Novel Axial-Transverse Flux Permanent Magnet Synchronous Machine

This paper analyzes a novel hybrid axial-transverse flux permanent magnet (PM) synchronous motor achieving high torque density. The stator pole pitch and the rotor pole pitch are the same. The motor is suitable for vehicle traction systems. The new axial-transverse machine has a single-sided or double-sided air gap. The machine has two adjacent quasi-U stator cores with ring-type winding, and the rotor has two PM groups, one outer and one inner. The shape of quasi-U stator core allows changing the flux path without changing power supply polarity. The analytical expressions of the no-load back-EMF and the torque are derived, after the development of 3-D magnetic equivalent circuit (MEC) model. The 3-D finite element method (FEM) is used to analyze the magnetic field, torque, and cogging torque for different skewings of the PMs.

Imaging quality evaluation method of pixel coupled electro-optical imaging system

With advancements in high-resolution imaging optical fiber bundle fabrication technology, traditional photoelectric imaging system have become “flexible” with greatly reduced volume and weight. However, traditional image quality evaluation models are limited by the coupling discrete sampling effect of fiber-optic image bundles and charge-coupled device (CCD) pixels. This limitation substantially complicates the design, optimization, assembly, and evaluation image quality of the coupled discrete sampling imaging system. Based on the transfer process of grayscale cosine distribution optical signal in the fiber-optic image bundle and CCD, a mathematical model of coupled modulation transfer function (coupled-MTF) is established. This model can be used as a basis for following studies on the convergence and periodically oscillating characteristics of the function. We also propose the concept of the average coupled-MTF, which is consistent with the definition of traditional MTF. Based on this concept, the relationships among core distance, core layer radius, and average coupled-MTF are investigated.Results show that the coupled-MTF oscillation converges to a fixed value when the deviation between a spatial frequency of input signal and Nyquist frequency is 1% and when the total number of pixels in the coupled system is more than 1000. The minimal frequency deviation corresponds to the slow velocity of the oscillational convergent. The oscillation amplitude of coupled-MTF differs in tangential and sagittal directions in a manner related to the corresponding pixel coupling error. The coupled-MTF periodically oscillates with the alignment error between the coupled pixel. One cycle is equivalent to the diameter of fiber cladding. The observation from the simulations further reveal that the distance between adjacent fiber cores and the dimension of core layer are directly related to the system imaging quality and the signal-to-noise ratio. Moreover, the average coupled-MTF can be used to quantitatively describe the function of related parameters and the imaging quality of the system.

Protonation-induced color change of an amino group functionalized [Fe4(μ3-O)2]8+ cluster

Although synthetic efforts to prepare carboxylato-bridged tetranuclear iron(III) clusters have been well preformed, introducing of functional groups on the coordination ligands to tune the structural, spectroscopic and physical properties of the cluster remains unstudied. Using amino functionalized ligands bipy-NH2 and O2CPh-NH2, we have prepared a new cluster 1 ([Fe4O2 (O2CPh-NH2)7(bipy-NH2)2]·HO2CPh-NH2·(CH3CN)3·C2H5OH·OH) via a new precise orientated strategy starting from iron(II) compound. The cluster was characterized by UV–Vis, IR and Mossbauer spectroscopy, X-ray crystallography, cyclic voltammetric and magnetic studies. Results have shown that the [Fe4(μ3-O)2]8+ core was disposed in a bent “butterfly” arrangement, and the adjacent cores were connected into 1-D chain via hydrogen-bonding contacts involving lattice OH− anion, HO2CPh-NH2 and solvent molecules. This 1D chain exhibits strong antiferromagnetic interactions, and irreversible electron reduction of one iron(III) ion to iron(II) at EP.C = −1.77 V vs SCE. Remarkably, color change from reddish violet to bluish green have been observed for this cluster upon protonating the amino functional groups.

Formation of wide binary stars from adjacent cores

Wide gravitationally bound pairs of stars can be formed from adjacent prestellar cores that happen to move slowly enough relative to each other. These binaries are remnants of the primordial clustering. It is shown that the expected fraction of wide bound pairs in low-density star formation regions can be larger than the fraction of wide pairs in the field. On the other hand, wide binaries do not form or survive in dense clusters. Recent works on the separation distribution of young binaries, summarized here, confirm these expectations. Alternative formation mechanisms of wide binaries such as cluster dissolution or unfolding of triple stars cannot explain the large observed fraction of young wide pairs and therefore are not dominant. The fact that more than a half of wide pairs contain subsystems matches the general multiplicity statistics and does not imply that hierarchical multiplicity and wide binaries are genetically related.

Tunable Supramolecular Helical Aggregate and Optoelectrical Properties of Perylene Diimides by Stereoisomerism of Sugar

In the present study, two sugar-based perylenediimide derivatives (PDIs) substituted at the imide positions with carbohydrate groups were synthesized to investigate the impact of the stereoisomerism of the sugar on the aggregation morphology and optoelectrical properties. The results showed that right-handed and left-handed helical nanowire fibers were obtained in tetrahydrofuran (THF)/H2O solution for α-d-glucopyranoside- and β-d-glucopyranoside-substituted PDIs, respectively. Determination of the electrical current in hydrazine vapor revealed that both sugar-based chiral PDIs exhibited enhanced current changes compared to their achiral counterpart because of the larger π–π orbital overlap between their adjacent perylene cores. A larger π–π orbital overlap and a smaller π–π interplanar spacing increased the electrical current of the α-d-glucopyranoside-substituted PDI more markedly than that of the β-d-glucopyranoside-substituted PDI. The results of this study suggest that the stereoisomerism of chiral s...

The reliability of asset management regime of the SROH using air void content of asphalt mixtures

ABSTRACTThe comparison pairs of cores (each 100 mm apart) from 68 reinstatements sites from various parts of the UK revealed that, the compounding consequences of generic non-homogeneous characteristics of hand laid recipe mixed materials (specified in Specification for the Reinstatement of Openings in Highways (SROH)) and high likeliness of being biased during air void (AV) testing makes the coring method extremely unreliable with very low repeatability and reproducibility. The wide-ranging maximum density reported in every instance in the comparison pair coring experiments meaningfully rationalizes the distorted homogeneity of materials. Although not only maximum density but also bulk density of adjacent cores located only 100 mm apart were found to be varied in the case of every pair in this study. Furthermore, the in situ performance shown by from 50 reinstatements after experiencing 1.5–10 years real-life ageing from various parts of the UK predictably indicates that either the linkage between the reinstatement with non-compliant AV and its impact on footways durability is non-proven or the reported AV content is extremely over estimated. At 95% level of significance, there exists enough evidence to conclude that, due to high uncertainty, very low repeatability and reproducibility and poor reliability with high chances of bias, the assessment of hand laid reinstatement work by AV testing will expose both the contractor and the client to unacceptable risk.

NiCo2O4 hollow microspheres with tunable numbers and thickness of shell for supercapacitors

We report a new resin formaldehyde (RF-COOH) microspheres hard templates based method to synthesize NiCo2O4 hollow microspheres with thin/thick single/double/triple-shell. Single-shell NiCo2O4 hollow microspheres are obtained with deionized water as solvent. Furthermore, ethylene glycol can decrease the aquo groups (H2O) number within the coordination sphere of Ni2+/Co2+, which leads to a decrease of hydrated metal ions size and more penetrated metal ions into RF microspheres that is essential to the formation of more shells. Thus, double and triple-shell NiCo2O4 hollow microspheres are harvested when ethylene glycol is solvent and the heating ramp rate are 2 and 5°C/min, respectively. Larger heating ramp rate (2–5°C/min) increases the temperature gradient of the infused RF microspheres, which favors the separation between adjacent NiCo2O4 layers and RF cores, and thus resulting in the formation of more shells. What’s more, shells become thick and more compact when the precursor concentration is increased from 0.05 to 0.1M due to more infused Ni2+/Co2+. The electrochemical performance for supercapacitors of NiCo2O4 hollow microspheres with thin multi-shells is superior to those with thick single-shell. The better performances are attributed to multi-shells with more electroactive sites and hollow structures as “ion-buffering reservoir”, while thin shell is beneficial to the diffusion of electrolyte/ions.

Design of Homogeneous Trench-Assisted Multi-Core Fibers Based on Analytical Model

We present a design method of homogeneous trench-assisted multicore fibers (TA-MCFs) based on an analytical model utilizing an analytical expression for the mode coupling coefficient between two adjacent cores. The analytical model can also be used for crosstalk (XT) properties analysis, such as XT reduction amount versus trench width, trench depth, and other fiber structural parameters as compared with normal step-index MCFs. Furthermore, the model can be used to search for core positions for further XT reduction in nonclose-packed structures. For instance, we show that a dual-ring structure is the quasi-optimum core layout starting from an one-ring structured 12-core fiber. Based on the analytical model, a square-lattice structured 24-core fiber and a 32-core fiber are designed both for propagation-direction interleaving (PDI) and non-PDI transmission schemes. The proposed model provides a powerful tool for designing high-count homogeneous TA-MCFs.

Rectangular Array Multicore Fiber Realizing Low Crosstalk Suitable for Next-Generation Short-Reach Optical Interconnects With Low Misalignment Loss

Toward the next-generation exa-scale short-reach optical interconnects (OIs) supporting large-capacity data transmission, a compact computer-compatible 8-core heterogeneous trench-assisted multicore fiber (TA-MCF) is proposed, in which cores are arranged in a rectangular array. To analyze the crosstalk (XT) between adjacent cores of TA-MCF OI, a rigorous full-vectorial H- field finite element method (FEM) and coupled power theory are applied. The impact of various trench design parameters on the mode-coupling coefficient C <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">mn</sub> and the coupling length L <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">c</sub> is discussed in detail. An accurate explicit condition for the achievement of low XT in an 8-core heterogeneous TA-MCF OI is obtained through numerical simulations. A rigorous modal solution approach based on the computationally efficient FEM and the least squares boundary residual method is employed to analyze the coupling loss caused by the misalignment to a butt-coupled TA-MCF OI.

On the very edge: faunal and functional responses to the interface between benthic seagrass and unvegetated sand assemblages

Changes in macrobenthic spatial structure were investigated across the precise 0.5 m wide boundary zone between intertidal seagrass and unvegetated sand in Moreton Bay, Queensland, Australia. Faunal abundance and species density in the marginal seagrass were only slightly reduced relative to local non-boundary areas. Although gradual diminution in seagrass faunal abundance occurred towards the interface and a few locally dominant species were absent from the boundary zone, most transition was far from gradual, instead being exactly coincident with the specific 0.1 m interface between the 2 habitats. Over this distance, faunal abundance and species density fell by 56 to 60% (from 1412 to 625 m-2 and from an estimated 42 species per sampling horizon to 17, respectively). Dominant seagrass species were abundant right up to the interface itself, but their densities had fallen by 82% a further 0.1 m into the adjacent sand. Functional-group density and diversity mirrored these changes, decreasing over the same distance by 30 to 36%. Spatial analysis showed that adjacent cores along lattice sampling horizons, although spaced further apart, were more similar to each other than were those oriented across horizons, even though these were contiguous. Characteristic high animal species richness in the seagrass relative to adjacent sand appears to be not so much related to characteristics of the seagrass habitat as a whole rather than to the presence or absence of individual plants. Asymmetrically, distributions of species characteristic of the sand stopped somewhat in advance of the interface, leaving a marginal sand zone dominated by generalists occurring at equal (low) species and population density across both habitats.

Effect of natural homointerfaces on the magnetic properties of pseudomorphic La0.7Sr0.3MnO3 thin film: Phase separation vs split domain structure

We studied the effect of naturally formed homointerfaces on the magnetic and electric transport behavior of a heavily twinned, 40nm thick, pseudomorphic epitaxial film of La0.7Sr0.3MnO3 deposited by molecular beam epitaxy on ferroelastic LaAlO3(001) substrate. As proved by high resolution X-ray diffraction analysis, the lamellar twin structure of the substrate is imprinted in La0.7Sr0.3MnO3. In spite of the pronounced thermomagnetic irreversibility in the DC low field magnetization, spin-glass-like character, possibly related to the structural complexity, was ruled out, on the base of AC susceptibility results. The magnetic characterization indicates anisotropic ferromagnetism, with a saturation magnetization Ms = 3.2μB/Mn, slightly reduced with respect to the fully polarized value of 3.7μB/Mn. The low field DC magnetization vs temperature is non bulklike, with a two step increase in the field cooled MFC(T) branch and a two peak structure in the zero field cooled MZFC(T) one. Correspondingly, two peaks are present in the resistivity vs temperature ρ(T) curve. With reference to the behavior of epitaxial manganites deposited on bicrystal substrates, results are discussed in terms of a two phase model, in which each couple of adjacent ferromagnetic twin cores, with bulklike TC = 370K, is separated by a twin boundary with lower Curie point TC = 150K, acting as barrier for spin polarized transport. The two phase scenario is compared with the alternative one based on a single ferromagnetic phase with the peculiar ferromagnetic domains structure inherent to twinned manganites films, reported to be split into interconnected and spatially separated regions with in-plane and out-of-plane magnetization, coinciding with twin cores and twin boundaries respectively.

Magnetostratigraphy of a long Quaternary sediment core in the South Yellow Sea

Continental shelves serve as a bridge between the continent and ocean and sediments in this region are sensitive to land-sea interaction, sea-level variation and local subsidence. In this study, we present a comprehensive magnetic study of the longest sediment core (CSDP-1, 300.1 m) recovered from the South Yellow Sea. The major magnetic minerals in the studied sediments are magnetite, hematite and greigite. Greigite records a chemical remanent magnetization, which can be removed effectively by thermal demagnetization. The magnetostratigraphy defined in this study contains the Matuyama-Brunhes boundary (M/B, 781 ka) at ∼73.68 m, which is consistent with results from adjacent cores. The base of the Quaternary (∼2.6 Ma) in the Yellow Sea is recovered for the first time at a depth of 227.16 m. The basal age of the core is estimated to be ∼3.50 Ma. It indicates that the first transgression of the Yellow Sea occurred no later than ∼1.7 Ma. Succeeding large amplitude regressions occurred in some cold periods such as during MIS 20, MIS 18, and MIS 10. Our results provide the first chronology that brackets the entire Quaternary and we reconstruct the sedimentary evolution of the Yellow Sea with robust age constraints, which provides an important framework for further paleoenvironmental and tectonic studies.

Differences in coastal subsidence in southern Oregon (USA) during at least six prehistoric megathrust earthquakes

Stratigraphic, sedimentologic (including CT 3D X-ray tomography scans), foraminiferal, and radiocarbon analyses show that at least six of seven abrupt peat-to-mud contacts in cores from a tidal marsh at Talbot Creek (South Slough, Coos Bay), record sudden subsidence (relative sea-level rise) during great megathrust earthquakes at the Cascadia subduction zone. Data for one contact are insufficient to infer whether or not it records a great earthquake—it may also have formed through local, non-seismic, hydrographic processes. To estimate the amount of subsidence marked by each contact, we expanded a previous regional modern foraminiferal dataset to 174 samples from six Oregon estuaries. Using a transfer function derived from the new dataset, estimates of coseismic subsidence across the six earthquake contacts vary from 0.31 m to 0.75 m. Comparison of subsidence estimates for three contacts in adjacent cores shows within-site differences of ≤0.10 m, about half the ±0.22 m error, although some estimates may be minimums due to uncertain ecological preferences for Balticammina pseudomacrescens in brackish environments and almost monospecific assemblages of Miliammina fusca on tidal flats. We also account for the influence of taphonomic processes, such as infiltration of mud with mixed foraminiferal assemblages into peat, on subsidence estimates. Comparisons of our subsidence estimates with values for correlative contacts at other Oregon sites suggest that some of our estimates are minimums and that Cascadia's megathrust earthquake ruptures have been heterogeneous over the past 3500 years.

Temperature-aware multi-application mapping on network-on-chip based many-core systems

As the number of processor cores increases and the core size shrinks, chip temperature has become a critical design issue for Network-on-Chip (NoC) based many-core systems. However, few task mapping methods consider temperature optimization, and even fewer in multi-application scenarios. In this paper, we propose a temperature-aware multi-application mapping scheme for NoC-based many-core systems. Chip temperature is reduced by balancing workloads among cores while few communication overheads are introduced. The applications are firstly partitioned into subgraphs, and the inter-subgraph communication is minimized. A submesh region is then allocated to each subgraph so as to avoid long distance communication. The processing speed of each core is estimated to decide the submesh size according to current temperature distribution, so the submesh allocation is efficient for balanced core temperatures. Finally, task mapping within each pair of subgraph and submesh is performed. The core temperatures, the heating of adjacent cores, chip layout and communication overheads are all considered. Besides, the voltage and frequency level of each task is also scaled down for temperature reduction while timing constraints are guaranteed. Experimental results show that the peak temperature is reduced by 4.8°C compared to current approaches and the temperature variance is reduced to 42% of the initial temperature variance. The energy consumption and communication overheads are also reduced.

Multiple 10Be records revealing the history of cosmic-ray variations across the Iceland Basin excursion

Cosmogenic 10Be is a proxy of cosmic-ray flux, and its natural records provide vital information about the past intensity variability of the geomagnetic field and solar activity. 10Be records also serve as powerful tools for global synchronization among a variety of paleoarchives and for elucidating sedimentary processes on natural remanent magnetization acquisition. However, high-resolution (multi-decadal to multi-centennial) records of 10Be are scarce, especially those older than several tens of thousands of years. Here we present multiple high-resolution 10Be records of the Iceland Basin geomagnetic excursion interval (ca. 170–200 kyr ago) obtained from sediment cores (authigenic 10Be/9Be ratio) and an ice core (atmospheric 10Be flux). Comparing sedimentary 10Be records with relative paleointensity from the same cores, we found differences in the magnetic lock-in depth, even between adjacent cores. The 10Be-proxy records from the sediment and ice cores exhibit common characteristics: an asymmetric large-scale variation, a ∼7-kyr quasi-plateau around the maximum with a characteristic mid-term depression, and multi-millennial fluctuations in cosmic-ray flux during this interval. Minimal-synchronized and stacked 10Be records show that maximum cosmic-ray flux occurred 188.5–190.0 kyr ago and was double the present flux. A wavelet analysis of the stacked curve reveals dominant 4-kyr and secondary 8-kyr periodicities, both of which can be interpreted as intrinsic geomagnetic cycles. The wavelet spectrum of the high-resolution ice-core record shows a periodicity of 1.7 kyr and somewhat intermingled multi-centennial cycles around the maxima of 10Be, which likely represent solar cycles in this period. High-resolution 10Be records from multiple paleoarchives provide both a robust proxy record of cosmic-ray flux and a valuable tool for detailed global synchronization based on cosmic-ray variations.

Efficient Voltage Regulation for Microprocessor Cores Stacked in Vertical Voltage Domains

Due to exponential (Moores law) scaling of advanced CMOS technologies, the challenges associated with delivering power to performance and mobile computing systems are outpacing the capabilities of conventional voltage regulator (VR) topologies. To continue to scale throughput at constant power density, the level of parallelism in microprocessor architectures is expected to increase substantially. In this paper, we present a power conversion topology to provide independent multicore regulation in the 0.8–1.4 V range from a 12-V dc bus. The topology uses a multistage ladder converter to manage power delivery to digital circuits stacked in vertical voltage domains. This approach has several advantages with regard to systems efficiency as it allows a more moderate conversion ratio of the main dc–dc converter. Moreover, the parallel converter only needs to process a fraction of the power of each core as the current can be “recycled” by adjacent cores in the stack. We develop a dynamical model for a multiple-input, multiple-output control scheme that uses a simple integral-control law, augmented with fast voltage- and current-mode feedforward. Measurement results of a discrete prototype verify the control scheme and demonstrate the potential advantages in system efficiency but also emphasize the remaining challenges in meeting stringent VR dynamic response requirements.

A study on the coupling coefficients for multi-core fibers

The complete analytical expressions of mode coupling dynamics for homogeneous 7-core multi-core fibers (MCFs) are obtained by using orthogonal coupled-mode theory (CMT). All the coupling coefficients between the adjacent cores, nonadjacent cores and self-coupling coefficients are taken into account, and proposed to be calculated by using their definition formulas rather than the frequently-used twin core fiber (TCF) model utilized in most publications before. Simulation results show that the coupling coefficients calculated by using the TCF model are smaller than that calculated by using definition formulas and consequently are not accurate, especially for strong coupling MCFs. Also the coupling coefficients between nonadjacent cores and self-coupling coefficients can be comparable to the coupling coefficients between adjacent cores, and consequently cannot be ignored in the analysis of strong coupling MCFs.