Vertical Block Research Articles

Solution of parametric vertical block linear complementarity problems

The parametric vertical block linear complementarity problem is introduced where the associated vertical block matrix and the column vector are parametric. Assuming the matrix to be a vertical block P-matrix, an algorithm is developed for solving vertical block linear complementarity problems. A necessary and sufficient condition is also derived to ensure the same solution basis for any parametric input of the vertical block P-matrix. Based on these, an algorithm is proposed and the solution of the parametric vertical block linear complementarity problem is obtained. A numerical example is presented to illustrate the use of the method.

Simple block patterns for the two-dimensional cutting problem

This paper presents an algorithm for the unconstrained two-dimensional cutting problem of rectangular pieces. It proposes the simple block (SB) pattern consisting of simple blocks. The SB pattern is defined recursively. Each cut on the stock plate produces just one simple block. A horizontal cut produces a horizontal block with width equal to that of the leftmost piece in the block. A vertical cut produces a vertical block with length equal to that of the bottommost piece in the block. The algorithm generates the optimal SB pattern recursively, and selects optimally the first piece in each block. It uses upper bound to prune some unpromising branches during the searching process. The computational results indicate that the algorithm is highly efficient in improving material utilization, and the computation time is reasonable.

Variation in seed protein and isoenzyme patterns in Cucurbita cultivars

The genetic variability in the seed proteins and the enzyme alcohol dehydrogenase (ADH) in representative species of the genus Cucurbita was studied. The banding patterns were obtained by means of vertical block electrophoresis in polyacrylamide gel. A specific protein components and ADH isoenzymes were established in the polymorphic banding patterns which can be applied individually or in combination as potential biochemical markers for breeding purposes.

Existence theory and Q-matrix characterization for the generalized linear complementarity problem: Revisited

We provide conditions under which a vertical block matrix is a Q-matrix if one or all representative sub-matrices are Q-matrices and vice versa. It is also shown, by means of counterexamples, that Eq. (3) of [A.A. Ebiefung, Existence theory and Q-matrix characterization for the generalized linear complementarity problem, Linear Algebra Appl. 223/224 (1995) 155–169] is incorrect.

68: Effectivness of vertical infraclavicular block for lower arm surgery

68: Effectivness of vertical infraclavicular block for lower arm surgery

Elasticity/saturation relationships using flow simulation from an outcrop analogue for 4D seismic modelling

Three production scenarios have been simulated for three displacement mechanisms using three lithofacies models built at two scales (fine and coarse) from a 2D outcrop analogue. Analysis of the flow simulation results and the associated seismic modelling investigate the dependence of the time-lapse response on the lithofacies model and the vertical grid block size. Elastic attribute quantification from coarse-grid models requires a decision on the type of fluid saturation distribution (uniform or patchy) within the coarse-grid blocks. Here, empirical relations for scaling up the fluid bulk modulus are developed which, when inserted into standard Gassmann calculations, permit calibration of the response for the coarse-grid block model from the finer-scale model. At the coarse scale, fluid saturation changes during water injection and pressure depletion can be represented adequately by these relations but, for gas injection, it appears necessary to refer back to the fine-scale models. For the case of gas injection they cannot be generalized readily for each different lithofacies model and are thus observed to be outcrop dependent.

Palaeomagnetically defined rotations of fault-bounded continental blocks in the North Anatolian Shear Zone, North Central Anatolia

The 1200 km-long North Anatolian Transform Fault connects the East Anatolian post-collisional compressional regime in the east with the Aegean back-arc extensional regime to the west. This active dextral fault system lies within a shear zone reaching up to 100 km in width, and consists of southward splining branches. These branches, which have less frequent and smaller magnitude earthquake activity compare to the major transform, cut and divide the shear zone into fault delimited blocks. Comparison of palaeomagnetic data from 46 sites in the Eocene volcanics from different blocks indicate that each fault-bounded block has been affected by vertical block rotations. Although clockwise rotations are dominant as expected from dextral fault-bounded blocks, anticlockwise rotations have also been documented. These anticlockwise rotations are interpreted as due to anticlockwise rotation of the Anatolian Block, as indicated by GPS measurements, and the effects of unmapped faults or pre-North Anatolian Fault tectonic events.

화상인식을 이용한 시각장애인용 보행보조장치

This paper presents the device of recognizing image of the studded paving blocks, transmitting, the information by vibration to a visually handicapped person. Usually the blind uses the walking stick to recognize the studded paving block. This research uses a PCA (Principal Component Analysis) based image processing approach for recognizing the paving blocks. We classify the studded paving blocks into 5 classes, that is, vertical line block, right-declined line block, left-declined line block, dotted block and flat block. The 8 images for each of 5 classes are captured for each block by 112*120 pixels, then the eigenvectors are obtained in magnitude order of eigenvectors by using principal component analysis. The principal components for images can be calculated using projection of transformation matrix composed of eigenvectors. The classification has been executed using Euclidean's distance, so the block having minimum distance with a image is chosen as matched one. The result of classification is transmitted to the blind by electric vibration signals with different magnitudes and frequencies.

Anesthesia and Prader–Willi syndrome: preliminary experience with regional anesthesia

The constellation of neonatal hypotonia, developmental delay, hypogonadism and obesity caused by hyperphagia was first reported in 1956 and subsequently termed Prader-Willi syndrome (PWS). Genetic analysis has demonstrated abnormalities of chromosome 15. Anesthesia concerns of PWS include morbid obesity, the potential for difficulties with airway management, risk for perioperative respiratory failure, abnormalities in the central control of ventilation and temperature, rare reports of primary myocardial involvement, aggressive and at times violent behavior and glucose intolerance. For the first time, we report the use of regional anesthesia in four patients with PWS. A lumbar plexus catheter was used to provide postoperative analgesia in one patient while regional anesthesia (fasica iliaca block, spinal anesthesia, and lateral vertical infraclavicular block) was used to provide primary intraoperative anesthesia in three other patients while avoiding the need for general anesthesia. Previous reports of the anesthesia care of patients with PWS are reviewed and the potential perioperative implications of the sequelae of PWS are discussed.

Insight into the Neogene tectonic history of the northern Bolivian Orocline from new paleomagnetic and geochronologic data

A paleomagnetic study of 36 sites (315 samples) of Neogene strata from the Peruvian Altiplano and adjacent sub‐Andean belt (Pilcopata area), combined with 40Ar/39Ar dating of 13 lava flows, provide new constraints on the Cenozoic deformation history of the northern Bolivian Orocline. In the Peruvian Altiplano, 40Ar/39Ar dating brackets the age of the strata sampled for paleomagnetism between 26.5 and 12.1 Ma for the Huaccochullo basin, 18.6 and 12.1 Ma for the Descanso‐Yauri basin, and 16.8 and 15.5 Ma for the Ayaviri basin. Sub‐Andean sediments are paleontologically constrained as Miocene, yet pre‐9 Ma. Prefolding magnetizations isolated in the Huaccochullo, Descanso‐Yauri, and Pilcopata localities indicate significant counterclockwise vertical axis block rotations of 11.3° ± 5.4°, 31.0° ± 10.2° and 7.8° ± 4.8°, respectively. The pattern of rotations together with mapped structures suggest that deformation of the northern Altiplano was partitioned into large regions experiencing relatively minor rotation versus smaller, isolated basins exhibiting high‐amplitude counterclockwise rotations that lie in a major left‐lateral shear zone. Our new results imply significant transpressional deformation occurred throughout the Peruvian Altiplano since circa 12 Ma and are integrated in a model detailing the tectonic evolution of the northern Bolivian Orocline since 25 Ma.

Reduction of blocking artifacts in JPEG compressed images

Image compression is a very important issue for several applications in the area of multimedia communications, the objective being reduction of storage and transmission costs. Many efficient coding techniques have been developed for various applications. Amongst them, the Joint Photographic Experts Group (JPEG) has been recommended for compression of continuous tone still images. However, the reconstructed images from JPEG compression produce annoying blocking artifacts near block boundaries, particularly in highly compressed images, because each block is transformed and quantized independently. Several techniques/algorithms have been proposed by researchers, both in spatial and frequency domains, for reduction of these artifacts with varied degree of success. These are briefly overviewed here. A new technique working in frequency domain, is proposed here by authors. This paper puts forth a method and an algorithm, working in frequency domain, for the detection and reduction of such blocking artifacts. These artifacts are modeled here as 2-D step functions between two neighboring blocks. Presence of the blocking artifacts is detected by using block activity based on human visual system (HVS) and block statistics. The boundary regions between blocks are identified as either smooth or non-smooth regions. The blocking artifacts in smooth regions are removed by modifying a few DCT coefficients appropriately, whilst an edge-preserving smoothing filter is applied to the non-smooth regions, i.e., genuine edges. The algorithm has been applied to variety of JPEG compressed images and results are compared with other postprocessing algorithms. The reduction in the blocking artifacts for each image have been evaluated using three indices, namely peak signal-to-noise ratio (PSNR), mean structure similarity (MSSIM) index based on human visual perception, and a new index, called here block boundary measure (BBM), applied to both vertical and horizontal block boundaries. The results show that the proposed method is very effective in detecting and reducing the blocking artifacts in JPEG compressed images.

Equivalence of the Generalized Vertical Block Linear Complementarity Problems and Linear Complementarity Problems

In this paper, generalization of a vertical block linear complementarity problem associated with two different types of matrices, one of which is a square matrix and the other is a vertical block matrix, is proposed. The necessary and sufficient conditions for the existence of the solution of the generalized vertical block linear complementarity problem is derived and the relationship between the solution set of the generalized vertical block linear complementarity problem and the linear complementarity problem is established. It is proved that the generalized vertical block linear complementarity problem has the P-property if and only if the vertical block linear complementarity problem has the P-property.

Vertical infraclavicular block is it an alternative for an axillary and a supraclavicular block?

Vertical infraclavicular block is it an alternative for an axillary and a supraclavicular block?

The Vertical Infraclavicular Brachial Plexus Block: A Simulation Study Using Magnetic Resonance Imaging

The recommended needle trajectory for the vertical infraclavicular brachial plexus block is anteroposterior, caudad to the middle of the clavicle. We studied the risk of pneumothorax and subclavian vessel puncture and the precision of this method by using magnetic resonance imaging in 20 adult volunteers. The trajectory aimed at the lung in six subjects, five of whom were women. However, pleural contact could be avoided in all subjects by halting needle advancement after contact with the subclavian vessels, plexus, or first rib. The subclavian vein was reached by the trajectory in three and the subclavian artery in five subjects. The trajectory had a median distance to the plexus (closest aspect) of 1 mm (range, 0-9 mm) and contacted the nerves in 9 subjects. In conclusion, there is a small probability that the needle may reach the pleura when a vertical infraclavicular brachial plexus block is performed, particularly in women, and a high probability that it will contact the subclavian vein or artery. Although the trajectory is close to the plexus, any medial deviation carries the risk of pleural or subclavian vessel contact at other depths. Clinical accuracy in defining the insertion point is critical.

Vertical infraclavicular brachial plexus block in children: a preliminary study

Vertical infraclavicular brachial plexus block in children: a preliminary study

Efficacy of vertical infraclavicular plexus block vs. modified axillary plexus block: a prospective, randomized, observer‐blinded study

Despite containing severe risks, infraclavicular approaches to the brachial plexus gained increasing popularity. Likewise, the vertical infraclavicular plexus block improved anesthesia compared to the standard axillary approach but contains the risk of pneumothorax. Therefore we modified the standard axillary technique by inserting a proximal directed catheter, referred to as a high axillary plexus block. We prospectively compared quality and onset of neural blockade after vertical infraclavicular plexus block (VIP) and high axillary plexus block (HAP) in two randomized groups (30 patients in each). In group VIP the insulated needle was inserted midway between the ventral process of the acromion and the jugular notch. In group HAP, first an axillary needle was placed. Through this a stimulating catheter was inserted in a proximal direction (10-15 cm); correct placement was confirmed by nerve stimulation. All patients received 40 ml ropivacaine 0.75% (300 mg). Discriminating between analgesia and anesthesia, a blinded observer assessed progression of neural blockade every 5 min for 60 min by pin prick. Incomplete blocks were supplemented 60 min after initial injection. All patients in both groups demonstrated sufficient surgical anesthesia. No patient needed systemic supplementation or general anesthesia. However, vertical infraclavicular plexus block indicated superior anesthesia compared to high axillary plexus block, regarding musculocutaneous, axillary and radial nerve, which were completely blocked with a higher success rate and in a shorter time interval (P < 0.05). While both techniques provide sufficient surgical anesthesia, vertical infraclavicular plexus block demonstrated a partially higher success rate and a faster onset than high axillary plexus block.

The time-domain electromagnetic response of wedge-like structures

Wedges are structures that vary in thickness from top to bottom over length. Despite their application to modelling the regolith, groundwater and bathymetric problems, wedges have not been studied in any great detail. We simulated the response of wedge-like structures using Tempest and HoisTEM-like AEM systems and a fixed-loop SIROTEM ground system. We found that it was very difficult to distinguish between the responses of wedges with different dips until smoke rings had penetrated the conductive outcropping wedge. This means that thinner wedges are easier to see than thicker wedges. It also implies that a vertical block might be a useful approximation to thicker wedges. Differentiation of wedge responses was best achieved using the vertical component of a fixed loop positioned off the wedge. Inline components of central-loop prospecting systems were useful as ``bump detectors'.

Basement-involved tectonics in North Fossa Magna, central Japan: The significance of the northern Itoigawa-Shizuoka Tectonic Line

The Toyama Trough and Fossa Magna basin are major transverse tectonic depressions located between northeast Japan (NEJ) and southwest Japan (SWJ). Itoigawa-Shizuoka Tectonic Line (ISTL), the western margin of Fossa Magna is a boundary between two tectonic provinces along the inner side of NEJ and SWJ. Abrupt lateral variations in thickness of the Middle to Upper Miocene strata are quite significant among these provinces in the North Fossa Magna. The development of the thrust/fold belt is attributed not only to horizontal compression but also to vertical block movements as basement-involved tectonics. In response to the Pliocene and later compression regime, the old fault-block boundaries were reactivated and produced differential block movement such as the tilting of the Central Upheaval Zone and uplifting of the Nishikubiki Belt. One possible model for the deeper geologic structure is presented that high-angled block faults on the surface among tectonic provinces originate in vertical weak zones in the deep seismogenic zone under the sedimentary layer. The folded Neogene system comprises the present-day thrust-fault province of the North Fossa Magna and the stress regime of strikeslip faulting occupies the basement, as inferred from focal mechanism solutions for small events. In order to account for the apparent discrepancy, a duplex stress field is possible for the active tectonics in the region.

Vertical infraclavicular brachial plexus block in children: a preliminary study

Brachial plexus blockade is a well-established technique in upper limb surgery. Among the infraclavicular approaches, the vertical infraclavicular brachial plexus (VIP) block is easy to perform and has a large spectrum of nerve blockade. The aim of this preliminary study was to determine the ease, effectiveness, safety, and duration of the VIP block in pediatric trauma surgery. Fifty-five patients (ASA physical status I and II, age range 5-17 years old) scheduled for upper limb trauma surgery received a VIP block under light general anesthesia, using 0.5 ml x kg(-1) of ropivacaine 0.5%. The number of attempts and time to perform the block, the occurrence of a surgical response, the visual analogue score (VAS) scores, the incidence of complications and the duration of the block were evaluated. The brachial plexus was found easily at the first or second attempt in 85% (47 of 55) of the cases, in 15% (eight of 55) of the cases it was localized after three to four attempts. The mean time to perform the block was 3.35 +/- 3.37 min. Ninety-eight percentage (54 of 55) of the blockades were effective for surgery and in just one case was ineffective. The VAS scores at the end of the procedure in 100% (55 of 55) of the cases were <3. There were no cases with clinical signs of pneumothorax nor inadvertent puncture of major vessels. Two patients developed a Horner's syndrome and in one a mild superficial hematoma at the puncture site occurred. The mean sensory block duration was 8.45 +/- 1.71 h and the mean motor block duration was 6.52 +/- 2.50 h. In this preliminary study, the VIP block was easy to perform, effective and free of major complications for pediatric trauma surgery. With the doses of ropivacaine we used it was useful for intra- and postoperative analgesia.

Skin-plexus depth of the brachial plexus performing a vertical infraclavicular block: A clinical observation

Skin-plexus depth of the brachial plexus performing a vertical infraclavicular block: A clinical observation