Outer Ones Research Articles

Straightforward Current Control – One Step Controller based on Current Slope Detection

SummaryIn order to control the speed or the position of an electrical drive, the torque of the machine has to be set accordingly. The torque is a function of the machine current which is set commonly by means of a voltage source power converter. Because of the simplification of the set-up procedure, cascaded control structures are used. For a stable operation it is important that the speed of the inner control loop is much higher than the outer ones. Hence the speed of the current control limits the dynamics of the drive control. This means that the speed and the accuracy of the current control is decisive for the overall performance of the drive control.In this paper a new control method will be presented which is capable to reach the setpoint value in the shortest possible time of only one control period (comp. fig. 7) but without the knowledge of the machine parameters. This is the fastest possible response for digital controls which can be obtained theoretically by deadbeat controllers. However, high dynamics can hardly be achieved by deadbeat controls in practice because they are very sensitive against variations of the control parameters. Therefore the machine parameters like the inductance and the resistance as well as the course of the induced voltage have to be determined by a measurement for a proper operation. Furthermore the control has to be adjusted manually by the user. This leads to an high effort for the set-up procedure. In addition these parameters may vary during operation because of warming for instance, which can lead to a maladjustment of the control.The new control will adapt onto the load automatically which leads to a significant simplification of the set-up procedure. The identification of the control path is based on the detection of the current slopes of the load current ripple, caused by the alternating of the switching states of the power converter. Hence no additional test pulse are necessary for the identification of the system behaviour. This permanent adaptation leads to an optimal dynamic behaviour of the drive system. In contrast to many model predictive control methods, the new control has a low computation effort and no extensive model of the control path is necessary.The principle function of this new control approach will be explained and verified for an armature current control of a d.c.-drive system. However the principles of this control can also be applied on three-phase application which will be demonstrated by experimental results.

Trojan capture by terrestrial planets

The paper is devoted to investigate the capture of asteroids by Venus, Earth and Mars into the 1:1 mean-motion resonance, especially into Trojan orbits. Current theoretical studies predict that Trojan asteroids are a frequent by-product of the planet formation. This is not only the case for the outer giant planets, but also for the terrestrial planets in the inner Solar System. By using numerical integrations, we investigated the capture efficiency and the stability of the captured objects. We found out that the capture efficiency is larger for the planets in the inner Solar System compared to the outer ones, but most of the captured Trojan asteroids are not long term stable. These temporary captures caused by chaotic behaviour of the objects were investigated without any dissipative forces. They show an interesting dynamical behaviour of mixing, like jumping from one Lagrange point to the other one.

FORCE DISTRIBUTION AND OFFSET CONFIGURATION FOR CARBON NANOTUBES

In this study, a novel semi-analytical approach is presented to evaluate the preferred position of an offset inner single-walled carbon nanotube (SWCNT) with reference to the cross-section of outer one. Moreover, on the basis of the continuum method utilized together with Lennard-Jones potential function, suction energy and acceptance condition for a SWCNT entering the outer one are investigated. Using netting analysis, the optimum configuration is determined to minimize the potential energy. To obtain the nature of interaction force, a universal potential curve is presented for an offset inner tube entering various semi-infinite outer ones. Lastly, based on the direct method, the mechanics of multi-walled carbon nanotubes (MWCNT) is investigated.

Presence and survival of Escherichia coli O157:H7 on lettuce leaves and in soil treated with contaminated compost and irrigation water

Escherichia coli O157:H7 outbreaks associated with produce consumption have brought attention to contaminated compost manure, and polluted irrigation water as potential sources of pathogens for the contamination of these crops. The aim of this study was to determine the potential transfer of E. coli O157:H7 from soil fertilized with contaminated compost or irrigated with contaminated water to edible parts of lettuce together with its persistence in soil under field conditions in two different seasons (fall and spring). Moreover, its survival on lettuce sprinkled with contaminated irrigation water was evaluated, as well as the prevalence of aerobic mesophilic, Enterobacteriaceae and Pseudomonadaceae in control lettuce samples. Four treatments, contaminated compost, surface and sprinkle irrigation with contaminated water and uninoculated pots, were used in this work. Contaminated compost was applied to soil in the pots before lettuce was transplanted and contaminated irrigation water was applied twice and three times on the plants after the seedlings were transplanted, for sprinkle and surface irrigation, respectively. E. coli O157:H7 survived in soil samples for 9weeks at levels, 4.50logcfugdw−1 (dw, dry weight) in fall and 1.50logcfugdw−1 in spring. The pathogen survives better in fall, indicating an important influence of environmental factors. E. coli O157:H7 population in lettuce leaves after sprinkle irrigation was very high (between 103 and 106cfug−1), but decreased to undetectable levels at field conditions. There was also transfer of E. coli O157:H7 from soil contaminated with compost or irrigated with contaminated water to lettuce leaves, mainly to the outer ones. The mean counts for aerobic mesophilic, Enterobacteriaceae and Pseudomonadaceae populations were also influenced by environmental conditions; higher levels were observed under fall conditions than in spring conditions. Contamination of lettuce plants in the field can occur through both contaminated composted manure and irrigation water and persist for several months.

Patterns of spatio‐temporal distribution of winter chronic photoinhibition in leaves of three evergreen Mediterranean species with contrasting acclimation responses

High irradiance and relatively low temperature, which characterize Mediterranean winters, cause chilling stress in plants. Downregulation of photosynthetic efficiency is a mechanism that allows plants to survive these conditions. This study aims to address whether this process shows a regular spatial pattern across leaf surface or not. Three species (Buxus sempervirens, Cistus albidus and Arctostaphylos uva-ursi) with contrasting responses to winter stress were studied. During 7 days, macro and micro Fv/Fm spatial patterns were monitored by the use of chlorophyll fluorescence imaging techniques. In the field, the strongest photoinhibition was found in B. sempervirens, while there was almost no chronic photoinhibition in C. albidus. In leaves of the first species, Fv/Fm decreased from base to tip while in C. albidus it was uniform over the leaf lamina. An intermediate behavior is shown by A. uva-ursi leaves. Spatial heterogeneity distribution of Fv/Fm was found inside the leaves, resulting in greater Fv/Fm values in the inner layers than in the outer ones. Neither xanthophyll-linked downregulation of Fv/Fm nor protein remobilization were the reasons for such spatial patterns since pigment composition and nitrogen content did not reveal tip-base differences. During recovery from winter, photoinhibition changes occurred in Fv/Fm, pigments and chloroplast ultrastructure. This work shows for the first time that irrespective of physiological mechanisms responsible for development of winter photoinhibition, there is an acclimation response with strong spatio-temporal variability at leaf level in some species. This observation should be taken into account when modeling or scaling up photosynthetic responses.

Zirconium on Benthic Foraminiferal Tests in the Arctic: A Plausible Shield towards Ocean Acidification

Foraminiferal samples from Kongsfjorden (Arctic Ocean) were analysed for elemental ratios using Energy Dispersive spectrometry (EDS), along with sediment organic carbon, grain size and trace metals (Zr and Hf). EDS results on benthic foraminifera N. labradorica tests surface indicated presence of zirconium (Zr), whereas other foraminiferal species like Elphidium excavatum, Cassidulina reniforme and Quinqueloculina stalkeri were devoid of any Zr traces. Both foraminiferal analysis (EDS) as well as sediment analysis (ICP-MS) indicated highest Zr percentage at the inner fjord station 4. Concentration of Zr showed opposite trend to salinity, temperature and organic carbon indicating that the source of Zr is through weathering of continental zircon. Zr showed close association with Hafnium (Hf) and the average Zr/Hf ratio within Kongsfjorden was 43. Benthic foraminiferal shells did not show any signs of dissolution. As Zr is resistant to any acid corrosion; it could possibly be protecting the foraminifera from dissolution. Hence, in the present study we conducted lab experiment on the benthic foraminifera from outer/ inner fjord by pH manipulation, to identify the possible effects on benthic foraminiferal tests in absence/presence of zirconium coating towards dissolution. Interestingly, at pH 6 foraminifera from inner fjord having Zr coating (as evidenced by EDS) did not show any dissolution, whereas outer fjord ones which are devoid of Zr shielding showed dissolution. These preliminary results indicate that with the continuing increase in atmospheric CO 2 it may be interesting to study the test structure of Zr encrusted foraminiferal tests in Kongsfjorden.

Optimization of the configuration of a symmetric three-barrier resonant-tunneling structure as an active element of a quantum cascade detector

On the basis of a model of rectangular potentials and different electron effective masses in wells and barriers of an open resonant-tunneling structure with identical outer barriers, a theory has been developed and the dynamic conductance caused by the interaction of the electromagnetic field with electrons passing through the structure has been calculated. Using the example of the three-barrier resonant-tunneling structure with In0.53Ga0.47As wells and In0.52Al0.48As barriers, it is shown that, independently of the geometrical sizes of potential wells and barriers, there exist three geometrical configurations (positions of the inner barrier with respect to outer ones) at which the nanosystem, as an active element, provides optimum operating conditions of the quantum cascade detector.

Histological Study and LYVE-1 Immunolocalization of Mouse Mesenteric Lymph Nodes with "In Vivo Cryotechnique"

The “in vivo cryotechnique” (IVCT) is a powerful tool to directly freeze living animal organs in order to maintain biological components in frozen tissues, reflecting their native states. In this study, mesenteric lymph nodes of living mice were directly frozen with IVCT, and we did morphological studies and immunohistochemical analyses on a hyaluronic acid receptor, LYVE-1. In lymph nodes, widely open lymphatic sinuses were observed, and many lymphocytes adhered to inner endothelial cells along subcapsular sinuses. The LYVE-1 was clearly immunolocalized at inner endothelial cells of subcapsular sinuses, as well as those of medullary sinuses. Conventional pre-embedding electron microscopy also showed LYVE-1 immunolocalization along both the apical and basal sides of cell membranes of inner endothelial cells. By triple-immunostaining for LYVE-1, smooth muscle actin, and type IV collagen, the LYVE-1 was immunolocalized only in the inner endothelial cells, but not in outer ones which were surrounded by collagen matrix and smooth muscle cells. Thus, the functional morphology of lymph nodes in vivo was demonstrated and LYVE-1 immunolocalization in inner endothelial cells of subcapsular sinuses suggests hyaluronic acid incorporation into lymph node parenchyma.

Mechanics of concentric carbon nanotubes: Interaction force and suction energy

Based on the continuum approximation together with Lennard–Jones potential, a new semi-analytical method is developed to determine the van der Waals interaction between two single-walled carbon nanotubes. Neglecting the frictional effects, acceptance condition and suction energy for an inner tube entering semi-infinite outer ones are obtained and nature of interaction force is investigated. The maximum suction energy configurations are found by netting analysis. Using this procedure, the optimum configurations are obtained to minimize the potential energy. Also, a universal potential curve is presented for an inner tube entering various semi-infinite outer ones. Finally, on the basis of the direct method, suction energy and acceptance condition are obtained for multi-walled carbon nanotubes.

Morphological organization of the dorsal protuberance of Linepithema humile (Mayr, 1868) ant's larvae (Hymenoptera, Formicidae)

The Argentine ant Linepithema humile is an important invasive species because of the levels of infestation that it can reach; however, there is little information about its presence, histological organization, and function of the dorsal protuberance, which is found exclusively in their larvae. The objective of this study was to describe it in L. humile through scanning electron microscopy and transmission electron microscopy, bringing information about this structure. The epidermis of these larvae have cuticles covering the whole body, and is formed by a sequence of overlapping lamellas where the inner ones were thicker and presented lower electron density, whereas the outer ones were thinner and highly electron dense. Pores or pore-like channels were not observed. A thick and acellular region composed of granular material was found under the cuticular layer. Out of this region, the flattened epidermic cells formed an epithelial layer. For the dorsal protuberance region, these cells become prismatic, and similarly to the cuticle, presents significant thickening. These cells presented extended microvilli, as well as a great amount of lamellar rough endoplasmic reticulum. Under this epithelium was observed a concentration of fat body cells, more numerous in the dorsal protuberance region. This study indicated that the dorsal protuberance present in the first segment of L. humile larvae has apparently no secretory function because no pores were found. This fact allowed to conclude that in L. humile larvae the dorsal protuberance would have the function to make it easier for the worker ants to carry them within the colony.

Transfer of Listeria innocua from contaminated compost and irrigation water to lettuce leaves

Many foodborne outbreaks of some pathogens such as Escherichia coli O157:H7, Salmonella or Listeria have been associated with the consumption of contaminated vegetables. Contaminated manure and polluted irrigation water are probable vehicles for the pathogens. The aim of this study was to determine the potential transfer of Listeria innocua from soil fertilized with contaminated compost or irrigated with contaminated water to the edible parts of lettuce grown on these soils together with its survival in lettuce and in soil under field conditions during two different seasons. Moreover, its survival on lettuce sprinkled with contaminated irrigation water was evaluated. L. innocua survived in soil samples for 9 weeks at high concentrations, 10 5 cfu gdw −1 in fall and 10 3 cfu gdw −1 in spring. Pathogen survived better in fall, indicating an important influence of temperature and humidity. L. innocua population in lettuce leaves was very high on lettuce leaves after sprinkling, but decreased to undetectable levels at field conditions. There was also transfer of L. innocua from soil contaminated with compost or irrigated with contaminated water to lettuce leaves, mainly to the outer ones. Survival profiles of L. innocua on lettuce and soil samples contaminated either by application of contaminated compost or surface irrigation water was similar. Our results indicated that contaminated compost and contaminated irrigation water can play an important role in the presence of foodborne pathogens on vegetables.

Low‐Nuclearity MnII Complexes Based on Pyrimidine‐4,6‐dicarboxylato Bridging Ligand: Crystal Structure, Ion Exchange and Magnetic Properties

AbstractThe use of 1,10‐phenanthroline (phen) has allowed the polymerisation process commonly occurring in manganese(II)/pyrimidine‐4,6‐dicarboxylate (pmdc) systems to be blocked off giving the first examples of low‐nuclearity coordination compounds containing the pmdc dianion, namely, the dimeric [Mn2(μ‐pmdc)2(H2O)2(phen)2]·8H2O compound (1) and the tetrameric [Mn4(μ‐pmdc)3(phen)4(H2O)4](X)2·11H2O[X = BF4– (2), ClO4– (3), NO3– (4)] complexes. X‐ray analyses show that the hexacoordinate MnII atoms are bridged by pmdc dianions that exhibit an asymmetric κ2N,O:κO′ coordination mode in compound 1 and adopt a bis‐bidentate κ2N,O:κ2N′,O′ binding pattern in the tetrameric units of compounds 2–4. The distorted octahedral O3N3 donor set of the metal centres in 1 is completed by two nitrogen atoms from a phenanthroline ligand and one water molecule. In the linear zigzag shaped tetrameric cations of compounds 2–4, the two inner manganese centres with a O2N4 donor set are, in addition, coordinated to two nitrogen atoms from a phenanthroline ligand, whereas the outer ones complete their O3N3 coordination environment with a bidentated phenanthroline ligand and two cis coordinated water molecules. The crystal packing of the complex units generates voids filled by hydrogen‐bonded C3‐like water chains in compound 1, whereas compounds 2–4 resemble a 3D open‐framework in which the channels are occupied by the counterions and the water molecules of crystallisation. Ion exchange tests were carried out showing that compound 4 exhibits a high capacity to capture other inorganic anions by releasing nitrates. Cryomagnetic susceptibility measurements have shown the occurrence of weak antiferromagnetic interactions (J = –0.06, –0.21, –0.26 and –0.25 cm–1 for compounds 1–4, respectively). The magneto‐structural analysis indicates that the magnetic interaction taking place through the μ‐pyrimidine ring, although being weak, predominates over the longer exchange pathway involving the two carboxylate groups of the pmdc ligand.

Спонтанно активні іонні канали мембран ядерної оболонки

The genetic apparatus of the eukaryotic cells is enclosed by the nuclear envelope, which consists of two membranes, the inner and the outer ones, and can be regarded as the specific part of the endoplasmatic reticulum of the cell. There are nuclear pores in the nuclear membranes--complexes, which provide the highly selective transport of macromolecules and passive transport of ions and small molecules. Besides, ion channels selective to cations and anions were described in the inner and the outer nuclear membranes. The physiological significance of these channels is not still clear because of the difficulty of access for the direct electrophysiological investigation, but we can suppose that they can play an important role in the ion balance between the cytoplasm/nucleoplasm and the nuclear lumen. In this review we gathered and analyzed data about spontaneously active ion channels which were found in the membranes of the nuclear envelope from cells of different types and tried to propose their functional meaning.

In-plane perturbation of a system of two coplanar slit-cracks – II: Case of close inner crack fronts or distant outer ones

The study of the in-plane perturbation of a system of two coplanar slit-cracks carried out in Part I is specialized to the case where the distance between the inner crack fronts is small, or equivalently that between the outer fronts large. The limit process involved is complex because of appearance of a “boundary layer” in the limiting case considered; this boundary layer occurs near the origin in the Fourier space used to determine the unknown components of the fundamental kernel looked for. A technique of matched asymptotic expansions is used to tackle this difficulty. The problem is thus reduced to determining two unknown functions only, which characterize the “interactions” between the two inner fronts. These functions obey a system of nonlinear differential equations in Fourier’s space, which are solved analytically near the origin and numerically in general. The results evidence a very slow decrease of long-range interactions between distinct points on the same front or distinct ones. This represents a striking difference with respect to the cases considered earlier of a single semi-infinite crack and a single slit-crack.

Superconductivity and oxygen ordering correlations in the homologous series of(Cu,Mo)Sr2(Ce,Y)sCu2O5+2s+δ

A detailed study of the structure-property relationship is reported for the first four members of the high-${T}_{\text{c}}$ superconducting homologous series of $(\text{Cu},\text{Mo}){\text{Sr}}_{2}{(\text{Ce},\text{Y})}_{s}{\text{Cu}}_{2}{\text{O}}_{5+2s+\ensuremath{\delta}}$ $[(\text{Cu},\text{Mo})\text{\ensuremath{-}}12s2]$. In this series, the adjacent ${\text{CuO}}_{2}$ planes are separated by a single Y-cation layer for $s=1$ and a fluorite-type $(\text{Ce},\text{Y})\text{\ensuremath{-}}{[{\text{O}}_{2}\text{\ensuremath{-}}(\text{Ce},\text{Y})]}_{s\text{\ensuremath{-}}1}$ layer block for $s\ensuremath{\ge}2$. Even though this series may be considered a conventional homologous series from the chemical point of view, we emphasize that the structures are different from those of the Tl-, Hg-, Bi-, etc.,-based series by the fact that the inserted fluorite-type blocks are insulating. We show the formation of the higher $s$ members via intercalation of additional ${\text{Ce-O}}_{2}$ layer(s) into the crystal lattices of the lower members of the series. Neutron powder-diffraction data demonstrate that the Ce/Y ratio is not constant at the different (Ce,Y) layers in the fluorite-structured block and that the innermost (Ce,Y) layer(s) are significantly Ce rich compared with the outer ones. Two independent crystallographic sites are identified for the extra oxygen atoms in the basal $({\text{Cu}}_{0.75}{\text{Mo}}_{0.25}){\text{O}}_{1+\ensuremath{\delta}}$ plane with site fractional occupancies that strongly correlate with the properties of the material. A short-range ordered structure is proposed for the $({\text{Cu}}_{0.75}{\text{Mo}}_{0.25}){\text{O}}_{1+\ensuremath{\delta}}$ layers that could explain both the superconducting properties of the materials and the enhanced ${T}_{\text{c}}$ for the first member of the series.

Fruit size decline from the margin to the center of capitula is the result of resource competition and architectural constraints

Plants produce repeated structures, such as leaves, flowers, and fruits, which differ in size and shape. One example of this is fruit size, which is commonly observed to decrease from proximal to distal positions within an inflorescence. The resource limitation hypothesis proposes that because proximal fruits usually develop first, they have temporal priority on access to resources over distal fruits. The non-mutually exclusive architectural effects hypothesis suggests that these position effects in fruit size may also be due to inherent architectural variation along infructescence axes. We separated out the effects of resource competition and inflorescence architecture by removing the outer or the inner flowers within capitula of Tragopogon porrifolius. We also studied if fruit position influenced germination and seedling performance in order to assess fitness consequences of position effects. Inner fruits were significantly heavier when outer flowers were removed. However, outer fruits did not significantly increase when inner flowers were removed, suggesting later fruits were limited by the development of early fruits. Our findings also suggest that architectural constraints restricted the size of inner fruits in comparison with outer ones. We found that both resource competition and inflorescence architecture affected the fruit size of T. porrifolius, even though this species does not have linear, indeterminate inflorescences. We advance the hypothesis that, when such effects on fitness occur, resource competition-mediated position effects could turn, in evolutionary time, into architectural position effects.

The interplay of chaos between the terrestrial and giant planets

We report on some simple experiments on the nature of chaos in our planetary system. We make the following interesting observations. First, we look at the system of Sun + four Jovian planets as an isolated five-body system interacting only via Newtonian gravity. We find that if we measure the Lyapunov time of this system across thousands of initial conditions all within observational uncertainty, then the value of the Lyapunov time seems relatively smooth across some regions of initial condition space, while in other regions it fluctuates wildly on scales as small as we can reliably measure using numerical methods. This probably indicates a fractal structure of Lyapunov exponents measured across initial condition space. Then, we add the four inner terrestrial planets and several post-Newtonian corrections such as general relativity into the model. In this more realistic Sun + eight-planet system, we find that the above structure of chaos for the outer planets becomes uniformly chaotic for almost all planets and almost all initial conditions, with a Lyapunov time-scale of about 5–20 Myr. This seems to indicate that the addition of the inner planets adds more chaos to the system. Finally, we show that if we instead remove the outer planets and look at the isolated five-body system of the Sun + four terrestrial planets, then the terrestrial planets alone show no evidence of chaos at all, over a large range of initial conditions inside the observational error volume. We thus conclude that the uniformity of chaos in the outer planets comes not from the inner planets themselves, but from the interplay between the outer and inner ones. Interestingly, however, there exist rare and isolated initial conditions for which one individual outer planetary orbit may appear integrable over a 200-Myr time-scale, while all the other planets simultaneously appear chaotic.

Transport and interaction blockade of cold bosonic atoms in a triple-well potential

We theoretically investigate the transport properties of cold bosonic atoms in a quasi-one-dimensional (1D) triple-well potential that consists of two large outer wells, which act as microscopic source and drain reservoirs, and a small inner well, which represents a quantum-dot-like scattering region. Bias and gate ‘voltages’ introduce a time-dependent tilt of the triple-well configuration, and are used to shift the energetic level of the inner well with respect to the outer ones. By means of exact diagonalization considering a total number of six atoms in the triple-well potential, we find diamond-like structures for the occurrence of single-atom transport in the parameter space spanned by the bias and gate voltages. We discuss the analogy with Coulomb blockade in electronic quantum dots, and point out how one can infer the interaction energy in the central well from the distance between the diamonds.

What does the commonly used DCF test for oxidative stress really show?

H(2)DCF-DA (dihydrodichlorofluorescein diacetate) is widely used to evaluate 'cellular oxidative stress'. After passing through the plasma membrane, this lipophilic and non-fluorescent compound is de-esterified to a hydrophilic alcohol [H(2)DCF (dihydrodichlorofluorescein)] that may be oxidized to fluorescent DCF (2',7'-dichlorofluorescein) by a process usually considered to involve ROS (reactive oxygen species). It is, however, not always recognized that, being a hydrophilic molecule, H(2)DCF does not cross membranes, except for the outer fenestrated mitochondrial ones. It is also not generally realized that oxidation of H(2)DCF is dependent either on Fenton-type reactions or on unspecific enzymatic oxidation by cytochrome c, for neither superoxide, nor H(2)O(2), directly oxidizes H(2)DCF. Consequently, oxidation of H(2)DCF requires the presence of either cytochrome c or of both redox-active transition metals and H(2)O(2). Redox-active metals exist mainly within lysosomes, whereas cytochrome c resides bound to the outer side of the inner mitochondrial membrane. Following exposure to H(2)DCF-DA, weak mitochondrial fluorescence was found in both the oxidation-resistant ARPE-19 cells and the much more sensitive J774 cells. This fluorescence was only marginally enhanced following short exposure to H(2)O(2), showing that by itself it is unable to oxidize H(2)DCF. Cells that were either exposed to the lysosomotropic detergent MSDH (O-methylserine dodecylamide hydrochloride), exposed to prolonged oxidative stress, or spontaneously apoptotic showed lysosomal permeabilization and strong DCF-induced fluorescence. The results suggest that DCF-dependent fluorescence largely reflects relocation to the cytosol of lysosomal iron and/or mitochondrial cytochrome c.

Sensitivity study of micro four-point probe measurements on small samples

The authors calculate the sensitivities of micro four-point probe sheet resistance and Hall effect measurements to the local transport properties of nonuniform material samples. With in-line four-point probes, the measured dual configuration sheet resistance is more sensitive near the inner two probes than near the outer ones. The sensitive area is defined for infinite film, circular, square, and rectangular test pads, and convergent sensitivities are observed for small samples. The simulations show that the Hall sheet resistance RH in micro Hall measurements with position error suppression is sensitive to both local carrier density and local carrier mobility because the position calculation is affected in the two pseudo-sheet-resistance measurements needed for the position error suppression. Furthermore, they have also simulated the sensitivity for the resistance difference ΔRBB′ of two specific configurations to clarify the effect of the calculated position, which results in an unexpected sensitivity to the local carrier mobility.