High Correction Capability Research Articles

A Novel Efficient Secure and Error-Robust Scheme for Internet of Things Using Compressive Sensing

In most of existing Internet of Things (IoT) applications, data compression, data encryption and error/erasure correction are implemented separately. To achieve reliable communication, in particular, in harsh wireless environment with strong interference, error/erasure correction codes with higher correction capability or Automatic repeat request (ARQ) scheme are desirable but at the cost of increasing complexity and energy consumption. Due to resource-constrained IoT device, it is often challenging to implement all of them. In this paper, we propose a novel lightweight efficient secure error-robust scheme, ENCRUST, which is able to achieve these three functions using simple matrix multiplication. ENCRUST is built on the new theoretical foundation of projection-based encoding presented in this paper, by leveraging the sparsity inherent in the signal. We perform theoretical analysis and experimental study of the proposed scheme in comparison with the conventional schemes. It shows that the proposed scheme can work in low SINR range and the reconstructed signal quality shows graceful degradation. Furthermore, we apply the proposed scheme on real-life electrocardiogram (ECG) dataset and images. The results demonstrate that ENCRUST achieves decent compression, information secrecy as well as strong error recovery in one go.

Outcome of Concomitant First Metatarsophalageal and Tarsometatarsal Arthrodesis for Severe Hallux Valgus

Category:Bunion; Midfoot/ForefootIntroduction/Purpose:Arthrodesis of the first tarsometatarsal (TMT-1) joint is a widely accepted procedure for treatment of hallux valgus (HV) with medial column instability secondary to unstable first ray, midfoot arthritis, and severe or recurrent deformities with high intermetatarsal angles (IMA). Similarly, metatarsophalangeal fusion (MTP-1) has been suggested for severe hallux valgus, metatarsophalangeal arthritis, and severe or recurrent deformities. Prior studies have demonstrated early outcomes in a small sample of patients. This study aimed to evaluate clinical and radiographic outcomes in patients with severe HV who underwent concomitant TMT-1 and MTP-1 arthrodesis for severe HV.Methods:All patients with symptomatic severe HV who failed conservative management and underwent concomitant MTP-1 and TMT-1 arthrodesis between January 2006 to December 2018 were included in our retrospective case series. Patients were operated on by one of three senior foot and ankle surgeons at a single tertiary center. Demographics, clinical outcomes, patient comorbidity information, and radiographic outcomes including baseline hallux valgus angle (HVA), IMA 1-2, hallux valgus interphalangeus angle, distal metatarsal articular angle, and sesamoid station were collected. The primary outcome was reoperation. Secondary outcomes were minor complications (local wound care, use of antibiotics, and skin dehiscence), visual analogue scale (VAS) pain scores, and change in radiographic measurements.Results:From 2006 to 2018, 42 patients (21.4% male, 78.6% female) at an average age of 62.6 years (range 48 to 80) met inclusion. At final average clinical follow up of 28 months, there were a total of 23 reoperations in 35.7% of patients at an average 18.5 months from index surgery (n=15; 1 revision TMT, 2 revision MTP, 1 hallux interphalangeal (IP) fusion, and 11 hardware removal). Minor complications were present in 7.1% of patients (n=3; 3 local wound care, 2 use of antibiotics, and 3 skin dehiscence). Average VAS score preoperatively and postoperatively was 5.5 to 1.9, respectively. Average preoperative HVA and IMA 1-2 angles were 35.6 and 15.3 degrees compared to postoperative angles of 9.0 and 9.3 degrees, respectively.Conclusion:The present study demonstrates concomitant MTP-1 and TMT-1 arthrodesis in cases of HV secondary to medial column instability secondary to unstable first ray, midfoot arthritis, and severe or recurrent deformities with high IMA has a high correction capability and achieved normal HVA as well as normal IMA 1-2 at greater than two years. Concomitant MTP-1 and TMT-1 arthrodesis in patients with severe HV appeared to be safe and clinically successful.

Reliability Analysis of Multibit Error Correcting Coding and Comparison to Hamming Product Code for On-Chip Interconnect

Error control schemes became a necessity in network-on-chip (NoC) to improve reliability as the on-chip interconnect errors increase with the continuous shrinking of geometry. Accordingly, many researchers are trying to present multi-bit error correction coding schemes that perform a high error correction capability with the simplest design possible to minimize area and power consumption. A recent work, Multi-bit Error Correcting Coding with Reduced Link Bandwidth (MECCRLB), showed a huge reduction in area and power consumption compared to a well-known scheme, namely, Hamming product code (HPC) with Type-II HARQ. Moreover, the authors showed that the proposed scheme can correct 11 random errors which is considered a high number of errors to be corrected by any scheme used in NoC. The high correction capability with moderate number of check bits along with the reduction in power and area requires further investigation in the accuracy of the reliability model. In this paper, reliability analysis is performed by modeling the residual error probability Presidual which represents the probability of decoder error or failure. New model to estimate Presidual of MECCRLB is derived, validated against simulation, and compared to HPC to assess the capability of MECCRLB. The results show that HPC outperforms MECCRLB from reliability perspective. The former corrects all single and double errors, and fails in 5.18% cases of the triple errors, whereas the latter is found to correct all single errors but fails in 32.5% of double errors and 38.97% of triple errors.

Técnicas para la implementación de turbo decodificadores con baja latencia

Turbo coding is a channel coding technique that increases the capacity of communications systems, especially wireless and mobile. Due to its high correction capability, this technique is used in modern wireless communication standards such as 3GPP and LTE/LTE-Advanced. One of the features of these systems is the increase in data processing capacity, where transmission rates of up to 1 Gbps are specified. However, the turbo coding technique inherently presents a limited performance as a consequence of the turbo decoding process at the reception stage. The turbo decoder presents a high operation latency mainly caused by the iterative decoding process, the interleaver and deinterleaver stage and the estimation process of the information bits. In this work, we show the techniques used to implement modern low-latency turbo decoders suitable for 3G and 4G standards.

ВИПРАВЛЕННЯ ПАКЕТІВ ПОМИЛОК НА ОСНОВІ МОДУЛЯРНОГО КОРИГУВАЛЬНОГО КОДУ

Запропоновано метод виправлення пакетів помилок на основі модулярного коригувального коду для підвищення надійності передачі даних у безпровідних сенсорних мережах. Для боротьби з пакетами помилок розроблено різні багатовимірні (каскадні, ітеративні) коди. Принцип роботи цих кодів полягає в послідовному використанні двох рівнів кодування і декодування даних. При цьому на кожному рівні кодування можна використовувати однакові за типом і коригувальною здатністю коди або різні. Перевагою багатовимірних кодів є їх висока коригувальна здатність, а недоліком – висока надлишковість. Розроблено двовимірну схему контролю помилок на основі модулярного коригувального коду. Модулярні коригувальні коди належать до символьних кодів, характеризуються низькою надлишковістю, дають змогу ефективно виявляти та виправляти одиничні символьні помилки. Принцип формування перевірних символів у двовимірному модулярному коді полягає в такому: спочатку обчислюють перевірні символи по рядках матриці даних; на наступному кроці обчислюють перевірні символи по стовпцях даних. Розроблено алгоритм виявлення та виправлення випадкових однократних помилок та пакетів помилок максимальною довжиною b = 3k – 2. Проведено експериментальні дослідження з виявлення та виправлення помилок у пакеті даних. Показано мінімальну та максимальну довжину та структуру помилок, яку може виправити цей код. Враховуючи низьку складність реалізації алгоритму декодування, цей коригувальний код планують використати для підвищення надійності передачі даних у безпровідних сенсорних мережах.

Combination of First Metatarsophalangeal Joint Arthrodesis and Proximal Correction for Severe Hallux Valgus Deformity

Arthrodesis of the first metatarso-phalangeal (MTP-1) joint is a widely accepted procedure for the treatment of hallux valgus in patients with MTP-1 degeneration, severe or recurrent deformity, or inflammatory arthritis. This study aimed to evaluate if an additional more proximal correction was beneficial in cases with a severely increased intermetatarsal 1-2 angle (IMA 1-2). A consecutive series of 18 feet (4 bilateral, all females; mean age, 61 years) with severe hallux valgus and an increased IMA 1-2 treated by MTP-1 fusion and an additional more proximal correction (Mau osteotomy or modified Lapidus procedure) was evaluated. Radiographs were analyzed for IMA 1-2 and hallux valgus angles (HVA), and for the position of the tibial sesamoid according to the AOFAS guidelines. At a mean followup of 14 months, all patients were satisfied or very satisfied with the results of surgery. There were no intraoperative complications. The IMA 1-2 significantly improved from a mean of 18.8 degrees before surgery to 4.6 degrees at followup (p < 0.001) and the HVA from a mean of 49.9 degrees to 9.7 degrees (p < 0.001), respectively. Sesamoid position improved two grades on average. We found no difference between the Mau osteotomy and the modified Lapidus procedure. The present results indicate that the combination of a more proximal procedure with a MTP-1 arthrodesis in cases of hallux valgus with severely increased IMA 1-2 has a high correction capability and achieved normal HVAs as well as normal IMAs 1-2. This technique appeared to be safe and clinically successful.

New anterior instrumentation for the management of thoracolumbar and lumbar scoliosis. Application of the Kaneda two-rod system.

The Kaneda multisegmental instrumentation is a new anterior two-rod system for the correction of thoracolumbar and lumbar spine deformities. This system consists of a vertebral plate and two vertebral screws for individual vertebral bodies and two semirigid rods to interconnect the vertebral screws. Clinical results of 25 thoracolumbar and lumbar scoliosis patients treated with this new instrumentation were analyzed. To evaluate the efficacy of the new anterior instrumentation in correction and stabilization of thoracolumbar and lumbar scoliosis. Since Dwyer first introduced the concept of anterior spinal instrumentation and fusion for scoliosis, anterior surgery has gradually gained acceptance. In 1976, a useful modification for the anterior spinal instrumentation, which reportedly provided means of lordosation and vertebral body derotation, was described. However, some authors reported a high tendency of the implant breakage, loss of correction, progression of the kyphosis, and pseudoarthrosis as the major complications. To overcome the disadvantages of Zielke instrumentation, the authors have developed a new anterior spinal instrumentation (two-rod system) for the management of thoracolumbar and lumbar scoliosis. Anterior correction and fusion using Kaneda multisegmental instrumentation was performed in 25 patients with thoracolumbar or lumbar scoliosis. The average follow-up period was 3 years, 1 month (range, 2 years to 4 years, 7 months). There were 20 patients with idiopathic scoliosis (13 adolescents and seven adults) and five patients with other types of scoliosis, including congenital and other etiologies. All patients had correction of scoliosis by fusion within the major curve, and for 16 of the 25 patients, the most distal end vertebra was not included in the fusion (short fusion). Radiographic evaluations were performed to analyze frontal and sagittal alignments of the spine. The average correction rate of scoliosis was 83%. Over the instrumented levels, the correction rate was 90%. Preoperative kyphosis of the instrumented levels of 7 degrees was corrected to 9 degrees of lordosis. Sagittal lordosis of the lumbosacral area beneath the fused segments averaged 51 degrees before surgery and was reduced to 34 degrees after surgery. The trunk shift was improved from 25 mm before surgery to 4 mm at final follow-up evaluation. The average improvement in the lower end vertebra tilt-angle was 97% in those patients whose lower end vertebra was included in the fusion and 83% in patients whose lower end vertebra was not included in the fusion. Apical vertebral rotation showed an average correction rate of 86%. At final follow-up evaluation, all patients demonstrated solid fusion without implant-related complications. There was 1.5 degrees of frontal plane and 1.5 degrees of sagittal plane correction loss within the instrumented area at final follow-up evaluation. New anterior two-rod system showed excellent correction of the frontal curvature and sagittal alignment with extremely high correction capability of rotational deformities. Furthermore, correction of thoracolumbar kyphosis to physiologic lordosis was achieved. This system provides flexibility of the implant for smooth application to the deformed spine and overall rigidity to correct the deformity and maintain the fixation without a significant loss of correction or implant failure compared with conventional one-rod instrumentation systems in anterior scoliosis correction.