Telemetry-Based Haptic Rendering for Racing Game Experience Improvement.

Many recent games, such as racing and flight games, open their game telemetry data to users by storing them in the local memory. Such telemetry data can provide useful information for haptic rendering, and this advantage has been exploited by the industry. This approach applies to any applications that export telemetry data in run time. The haptic rendering module operates as a separate process that accesses the telemetry data in parallel with the application. It is simple, efficient, and modular while retaining the application intact. We examine the approach's viability for user experience improvement by developing three telemetry-based haptic rendering algorithms for car racing games. They express the car engine response, collisions with external objects, and the road surface texture, respectively. Building a haptics-enabled driving platform, we conducted a user study comparing gaming experiences between our telemetry-based algorithms and conventional sound-to-tactile conversion algorithms. The results showed that the telemetry-based effects elicited better experiences than the sound-based effects.

Clinical Usefulness of SPECT/CT for Assessing Postoperative Outcomes After Medial Opening-Wedge High Tibial Osteotomy.

Background: Qualitative studies have explored changes in Tc-99m hydroxymethylene diphosphonate (HDP) uptake on single-photon emission computed tomography and computed tomography (SPECT/CT) as a result of offloading after medial opening-wedge high tibial osteotomy (MOWHTO) in patients with medial compartment knee osteoarthritis. However, whether changes in the Tc-99m HDP uptake on SPECT/CT reflect the degree of clinical improvement in postoperative outcomes, especially when using minimal clinically important differences (MCIDs), has not been investigated. Purpose: To investigate the association between changes in Tc-99m HDP uptake on SPECT/CT and MCID-based improvement on the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score in patients who underwent MOWHTO. Study Design: Cross-sectional study; Level of evidence, 3. Methods: The study included 35 knees in 31 patients who underwent MOWHTO. SPECT/CT was performed preoperatively and 3 years postoperatively with clinical and radiological assessments. On SPECT/CT, the knee joint was divided into 10 regions, and the radiotracer uptake amount of each region was divided by the uptake amount of the reference zone. Patients were divided into 2 groups based on whether they achieved the MCID of 16.1 points on the WOMAC at 3 years postoperatively, and changes in uptake amount on SPECT/CT were compared between the groups. Results: At 3 years postoperatively, 22 patients achieved the MCID on the WOMAC (62.9%; above-MCID group) and 13 patients did not (37.1%; below-MCID group). In the above-MCID group, significant improvement was observed in the WOMAC after MOWHTO (from 55.8 to 19.6; P < .05); however, significant improvement was not observed in the below-MCID group (from 38.8 to 32.3; P = .100). Based on mean change of uptake on SPECT/CT in each region, the above-MCID group showed significantly greater reduction of uptake on SPECT/CT than the below-MCID group in the femoral anteromedial compartment (P = .004), tibial anteromedial compartment (P = .009), and tibial anterolateral compartment (P = .031). Conclusion: Reduction in radiotracer uptake on SPECT/CT of the knee joint reflected clinical improvement in patient-reported outcomes following MOWHTO.

Influence of increased pain sensitivity on patient-reported outcomes following total knee arthroplasty.

PURPOSE: The purpose of this study was to discover whether increased pain sensitivity was associated with postoperative pain and patient-reported outcome measures (PROMs) after total knee arthroplasty (TKA). METHODS: Pain sensitivity was evaluated preoperatively using a pain sensitivity questionnaire (PSQ). Resting, walking, nighttime, and average pain visual analog scale (VAS) were measured before surgery and 6 weeks, 3 months, 6 months, and 1 year after surgery. PROMs were also evaluated based on the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score and patient satisfaction. The association between pain VAS average score, WOMAC total score, and PSQ score (minor, moderate, and total score) was assessed at each stage. RESULTS: There were 59 patients with a high PSQ score (≥ 5.2) and 53 with a low PSQ score (< 5.2). Up to 1 year postoperatively, the group with high PSQ scores had higher resting, walking, nighttime, and average pain VAS scores than the group with low scores (all p < 0.05). Worse preoperative WOMAC pain, function, and total scores continued until 1 year after surgery in the high-scoring PSQ group (all p < 0.05). The group with low PSQ scores was more satisfied with surgery than the group with high scores (p = 0.027). There was a positive correlation between preoperative PSQ score and pain VAS average score at all time points (all p < 0.05). A relationship between PSQ score and WOMAC total score was also observed (all p < 0.05). CONCLUSION: Increased pain sensitivity is a factor related to higher postoperative pain levels and inferior PROMs in patients undergoing primary TKA. LEVEL OF EVIDENCE: Case-controlled study, III.

Intravenous Tranexamic Acid Has Benefit for Reducing Blood Loss after Open-Wedge High Tibial Osteotomy: A Randomized Controlled Trial.

(1) Background: the purpose of this study was to investigate the efficacy and safety of intravenous (IV) administration of tranexamic acid (TXA) in patients undergoing medial opening wedge high tibial osteotomy (MOWHTO). (2) Methods: a total of 73 patients were randomly allocated into two groups (TXA group and control group). The primary outcome was total perioperative calculated blood loss after MOWHTO. Secondary outcomes included self-reported pain severity using a 10-point visual analog scale (VAS) and the EuroQol-5 Dimension (EQ-5D) questionnaire. The postoperative allogeneic transfusion rate and wound complications were compared. Deep vein thrombosis (DVT) incidence was compared by conducting DVT computed tomography imaging. (3) Results: the total blood loss after surgery was 470.9 mL in the TXA group and 739.3 mL in the control group, showing a significant difference (p < 0.001). There were no differences in pain VAS scores between the two groups (all p > 0.05). No difference in preoperative EQ-5D scores for any items existed between the two groups. No transfusion was performed in either group. There was no difference in DVT incidence or the rate of wound complications between the two groups. (4) Conclusion: in patients undergoing MOWHTO, IV TXA reduces total blood loss and drainage amount. However, no additional benefits in clinical outcomes, transfusion rate, or wound complications were apparent, with similar DVT incidence rates.

Efficacy and safety of celecoxib combined with JOINS in the treatment of degenerative knee osteoarthritis: study protocol of a randomized controlled trial.

BACKGROUND: The aim of this study will be to investigate the therapeutic effect and safety of non-steroidal anti-inflammatory drugs (NSAIDs) along with symptomatic slow-acting drugs for the treatment of osteoarthritis (SYSADOA), JOINS tablets, for degenerative knee osteoarthritis (OA) treatment and to determine the analgesic and anti-inflammatory effects of the combination therapy. In addition, we will investigate whether JOINS treatment alone after NSAID and JOINS combination treatment is effective in relieving and maintaining knee OA symptoms. METHODS: This study will be a prospective, randomized, double-blind endpoint study design. All patients will be randomly assigned to either intervention (celecoxib+JOINS) or control (celecoxib+placebo) groups. In Part 1, the intervention group will be administered celecoxib once a day and JOINS three times a day for a total of 12 weeks. In the control group, celecoxib will be administered once a day and JOINS placebo three times a day for a total of 12 weeks. In Part 2, JOINS alone and JOINS placebo alone will be administered for an additional 24 weeks in both groups, respectively. The primary endpoint will be the amount of change during the 12 weeks as assessed using the Western Ontario and McMaster Universities Osteoarthritis Index total score compared with baseline. The secondary endpoint will be the amount of change at 1, 4, 12, 24, and 36 weeks from the baseline for pain visual analog scale, Brief Pain Inventory, Short Form Health Survey-36 and biomarkers. RESULTS: The trial was registered with Clinical-Trials.gov (NCT04718649). The clinical trial was also registered on Clinical Research Information Service (CRIS) with the trial registration number KCT0005742. CONCLUSIONS: The combination treatment of the most commonly used SYSADOA drug, JOINS, and selective COX-2 inhibitor celecoxib as the representative NSAID for knee OA treatment, can be compared with celecoxib alone treatment to determine the safety or therapeutic effect.

Preemptive Duloxetine Relieves Postoperative Pain and Lowers Wound Temperature in Centrally Sensitized Patients Undergoing Total Knee Arthroplasty: A Randomized, Double-Blind, Placebo-Controlled Trial.

(1) Background: The purpose of this study was to determine whether preemptive duloxetine in patients with central sensitization (CS) is effective for acute postoperative pain control and wound healing following total knee arthroplasty (TKA). (2) Methods: CS was defined as a score of 40 points or higher on the Central Sensitization Inventory (CSI) survey. Thirty-nine patients with CS were randomly assigned to either the duloxetine group (n = 19) or the placebo group (n = 20). The duloxetine group took duloxetine 30 mg once a day, while the placebo group took the placebo medication once a day. A pain visual analog scale (VAS) and the Brief Pain Inventory (BPI), wound complications, the temperature of the surgical site, and adverse events were investigated. Skin temperature was measured at the center of the patella using a portable digital thermometer. (3) Results: The duloxetine group reported significantly lower pain VAS scores during follow-up periods up to 6 weeks after surgery (all p < 0.05). BPI interference also showed significantly superior results in the duloxetine group after surgery (all p < 0.05). Although there was no difference in the rate of wound complications between the two groups (p > 0.05), the duloxetine group showed significantly lower wound temperature than the placebo group during the follow-up period (all p < 0.05). (4) Conclusion: In this study, preemptive duloxetine effectively reduced pain and lowered wound temperature following TKA in CS patients.

Alignment adjustment using the Valgus stress technique can increase the surgical accuracy of novice surgeons during medial opening-wedge high Tibial osteotomy.

BACKGROUND: The purpose of this study was to compare the degree of accuracy of coronal alignment correction with use of the "alignment adjustment under valgus stress technique" between expert and novice surgeons during medial opening-wedge high tibial osteotomy (MOWHTO). METHODS: Forty-eight patients who underwent MOWHTO performed by an expert surgeon (expert group) and 29 by a novice surgeon (novice group) were enrolled in analysis. During surgery, lower-extremity alignment was corrected using the "alignment adjustment under valgus stress technique". Normocorrection was defined as a weight-bearing line ratio between 55 and 70% and the correction accuracy was compared between expert and novice groups using the ratio of normocorrection to outliers. The clinical outcomes were also compared using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) at 1 year after surgery. RESULTS: The undercorrection rate was 14.6% in the expert group and 13.8% in the novice group, while the overcorrection rate was 2.1% in the expert group and 3.4% in the novice group. In the ratio of normocorrection to outliers, no difference was found between the two groups at the one-year follow-up visit (83.3% in the expert group vs. 82.8% in the novice group; p > 0.05). Also, no significant differences were seen in WOMAC subscores immediately preoperatively and at 1 year after surgery (all p > 0.05). CONCLUSION: Adhering to the "alignment adjustment under valgus stress technique" protocol enabled novice surgeons to achieve similar surgical accuracy as that of an expert surgeon in coronal alignment during MOWHTO. LEVEL OF EVIDENCE: Level III.

The Minimal Clinically Important Difference (MCID) for the WOMAC and Factors Related to Achievement of the MCID After Medial Opening Wedge High Tibial Osteotomy for Knee Osteoarthritis.

BACKGROUND: Many approaches have been used to determine the minimal clinically important difference (MCID) in patients undergoing total knee arthroplasty, but the MCID for outcome measures after medial opening wedge high tibial osteotomy (MOWHTO) for the treatment of medial compartment knee osteoarthritis (OA) has not been reported. PURPOSE: To define the MCID for the Western Ontario and McMaster Universities Arthritis Index (WOMAC) after MOWHTO and to identify risk factors for not achieving the MCID. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: Among patients with medial compartment knee OA who underwent MOWHTO, 174 patients who were followed for 2 years were included in the study. The MCID and substantial clinical benefit (SCB) for the WOMAC were determined using the anchor-based method with a 15-item questionnaire. Preoperative OA severity was measured by the Kellgren-Lawrence (K-L) grading system, and the acceptable range of the postoperative weightbearing line ratio was 50% to 70%. Patients were divided into 2 groups based on whether the MCID and SCB were achieved, and then factors related to failure to achieve the MCID and SCB were analyzed using multivariate logistic regression analysis. RESULTS: The MCID for the WOMAC was 4.2 points for the pain subscale, 1.9 points for the stiffness subscale, 10.1 points for the function subscale, and 16.1 points for the total. Additionally, the SCB for the WOMAC was 6.4 for pain, 2.6 for stiffness, 16.4 for function, and 25.3 for the total. Overall, 116 (66.7%), 99 (56.9%), 127 (73.0%), and 128 (73.6%) patients achieved the MCID for the WOMAC pain, stiffness, function, and total, respectively, after MOWHTO. The odds of not achieving the MCID for the WOMAC total were 1.09 times greater (95% CI, 1.05-1.13; P < .001) in patients with a low preoperative WOMAC total score (cutoff values: 10.5 for pain, 3.5 for stiffness, 34.5 for function, and 51.0 for the total), 11.77 times greater (95% CI, 3.68-37.70; P < .001) in patients with K-L grade 4 OA compared with K-L grades 2 or 3 OA, and 8.39 times greater (95% CI, 2.98-23.63; P < .001) in patients with undercorrection or overcorrection. A low preoperative WOMAC score, K-L grade 4 OA, and undercorrection or overcorrection were also associated with not achieving the SCB for the WOMAC total (all P < .05). CONCLUSION: Patients treated with a MOWHTO require a 16.1-point improvement in the WOMAC total score to achieve a MCID from the procedure. Low preoperative WOMAC scores, severe OA, and undercorrection or overcorrection were related to failure to achieve the MCID.

2-Octyl Cyanoacrylate Topical Adhesive as an Alternative to Subcuticular Suture for Skin Closure After Total Knee Arthroplasty: A Randomized Controlled Trial in the Same Patient.

BACKGROUND: The 2-octyl cyanoacrylate topical adhesive with flexible self-adhesive polyester mesh (Dermabond Prineo) is becoming widely used in many surgical fields. However, no prior studies have tested the efficacy and safety of this topical adhesive compared with subcuticular suture in the same patient. The purpose of this study was to compare the efficacy and safety between Dermabond Prineo and subcuticular suture for skin closure in patients undergoing same-day bilateral total knee arthroplasties (TKAs). MATERIALS AND METHODS: A prospective, double-blind randomized controlled trial was performed in 51 patients scheduled to undergo same-day bilateral TKAs. One knee was randomly assigned to the Dermabond Prineo and the other knee was allocated to the subcuticular suture. As primary outcomes, Vancouver scar scale was evaluated at 6 months and Patient and Observer Scar Assessment Scale was evaluated at 2 weeks, 6 weeks, 3 months, and 6 months. Secondary outcomes included cosmesis efficacy (Hollander wound evaluation scale [HWES] and cosmesis visual analog scale [VAS]), time and pain efficiency (skin suture time, stitch out time, and stitch out pain VAS), and safety (wound complications during the 6-month follow-up period). The primary and secondary outcome measures were compared between groups. RESULTS: There were no significant differences in Vancouver scar scale and Patient and Observer Scar Assessment Scale at 6 months. Although there were no significant differences in HWES at 2 weeks, the Dermabond Prineo group showed better step-off border item of HWES. There was also no difference in cosmesis VAS at 6 months. The Dermabond Prineo group showed superior results in terms of time (suture time: Dermabond Prineo = 191 second (sec) ± 60.1 sec, subcuticular suture = 356.8 sec ± 92.3 sec; stitch out time: Dermabond Prineo = 4 sec ± 1.3 sec, subcuticular suture = 26.6 sec ± 4.2 sec, all P < .001) without significant differences in pain scale (P = .823) or wound complications (all P > .05). CONCLUSION: Comparing cosmetic efficacy, time efficiency, and safety, Dermabond Prineo provided quicker wound closure, shorter stitch out time, and better wound margin coaptation in the early postoperative period but similar cosmetic efficacy compared with subcuticular suture. Based on our study, Dermabond Prineo is a useful alternative to subcuticular suture in patients undergoing TKA. LEVEL OF EVIDENCE: Therapeutic level 1.

Serotype Distribution and Antimicrobial Resistance of Invasive and Noninvasive Streptococcus pneumoniae Isolates in Korea between 2014 and 2016.

BACKGROUND: Several factors contribute to differences in Streptococcus pneumoniae serotype distribution. We investigated the serotype distribution and antimicrobial resistance of S. pneumoniae isolated between 2014 and 2016 in Korea. METHODS: We collected a total of 1,855 S. pneumoniae isolates from 44 hospitals between May 2014 and May 2016, and analyzed the serotypes by sequential multiplex PCR. We investigated the distribution of each serotype by patient age, source of the clinical specimen, and antimicrobial resistance pattern. RESULTS: The most common serotypes were 11A (10.1%), followed by 19A (8.8%), 3 (8.5%), 34 (8.1%), 23A (7.3%), and 35B (6.2%). The major invasive serotypes were 3 (12.6%), 19A (7.8%), 34 (7.8%), 10A (6.8%), and 11A (6.8%). Serotypes 10A, 15B, 19A, and 12F were more common in patients ≤5 years old, while serotype 3 was more common in patients ≥65 years old compared with the other age groups. The coverage rates of pneumococcal conjugate vaccine (PCV)7, PCV10, PCV13, and pneumococcal polysaccharide vaccine 23 were 11.8%, 12.12%, 33.3%, and 53.6%, respectively. Of the 1,855 isolates, 857 (46.2%) were multi-drug resistant (MDR), with serotypes 11A and 19A predominant among the MDR strains. The resistance rates against penicillin, cefotaxime, and levofloxacin were 22.8%, 12.5%, and 9.4%, respectively. CONCLUSIONS: There were significant changes in the major S. pneumoniae serotypes in the community. Non-PCV13 serotypes increased in patients ≤5 years old following the introduction of national immunization programs with the 10- and 13-polyvalent vaccines.

Surgical accuracy, function, and quality of life of simultaneous versus staged bilateral Total hip Arthroplasty in patients with Osteonecrosis of the femoral head.

BACKGROUND: The optimal surgical option for patients requiring bilateral hip replacement remains controversial. The purpose of this study was to compare surgical accuracy; functional outcome and health-related quality of life; and prosthetic-related complications and revision surgery of a simultaneous bilateral total hip arthroplasty (THA) with those of a staged bilateral THA with an interval between procedures <12 months. METHODS: A total of 123 unselected consecutive patients (mean age, 43.3 years) who underwent bilateral THAs for osteonecrosis of the femoral head (ONFH) with a minimum follow-up of two years (mean, 60.2 months) were studied retrospectively; 63 simultaneous procedures served as a test group and 60 staged procedures served as a control group. RESULTS: The mean postoperative leg-length discrepancy (LLD) and the percentage of patients who had an LLD >3 mm were significantly lower in the simultaneous group (P < 0.001 and P = 0.001, respectively). A higher number of cups within the safe zones, a higher correction rate, and a lower failure rate for the cup placement in the second-operated hip were also identified in the simultaneous group. The mean Harris hip score, EuroQol-5D index, and EuroQol-visual analogue scale score were all better in the simultaneous group at the latest follow-up (P < 0.001, in all comparisons). We found that the simultaneous procedure was associated with a lower incidence of postoperative prosthetic-related complications and revision surgery. CONCLUSIONS: We suggest that bilateral ONFH could be treated with a simultaneous THA rather than a staged THA to achieve a better surgical outcome.

The Patient's Perception Does Not Differ Following Subvastus and Medial Parapatellar Approaches in Total Knee Arthroplasty: A Simultaneous Bilateral Randomized Study.

This simultaneous bilateral randomized study investigated whether patients would perceive the difference between the subvastus approach (SVA) and the medial parapatellar approach (MPA) after total knee arthroplasty (TKA). In 50 patients scheduled to undergo same-day bilateral TKA, one knee was randomly assigned to SVA and the other to MPA. Patient-reported measures (pain, Western Ontario McMaster University Osteoarthritis Index score, and side preference) and physician-assessed measures (isokinetic muscle strength, range of motion, and Knee Society score) were compared. No differences were observed in the patient-reported measures and physician-assessed measures, with the exception of greater quadriceps strength at postoperative 1 week in knees that underwent SVA. Patients receiving contemporary perioperative management after same-day bilateral TKA do not perceive any difference between knees that underwent SVA or MPA.

Clinical Relevance of the SRS-Schwab Classification for Degenerative Lumbar Scoliosis.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: The aim of this study was to evaluate the clinical relevance of the SRS-Schwab classification for degenerative lumbar scoliosis (DLS). SUMMARY OF BACKGROUND DATA: The SRS-Schwab classification has been presented and validated as a useful tool for adult spinal deformity (ASD). This classification includes various types of ASD (degenerative de novo scoliosis or adult form of idiopathic scoliosis). However, DLS has different clinical characteristics and pathophysiology compared with other forms of ASD. METHODS: In this retrospective cohort study, 216 (146 conservatively treated and 70 surgically treated) DLS patients were enrolled. The average patient age was 72.1 ±â€Š7.4 years. Clinical parameters for disability were measured using Oswestry disability index (ODI) and back and leg pain numerical rating scale. Radiographic parameters included SRS-Schwab sagittal modifiers (pelvic tilt [PT]; sagittal vertical axis [SVA];pelvic incidence-lumbar lordosis [PI-LL]), T1 pelvic angle, and coronal parameters (Cobb's angle [CA]; coronal imbalance [CI]; coronal deviation distance [CDD]; tilting angle [TA]). Correlations between clinical parameters and radiographic parameters were assessed and surgical rates along the SRS-Schwab sagittal modifiers were evaluated. RESULTS: Only PI-LL as a sagittal radiographic parameter showed a weak correlation with clinical parameters (r = 0.137-0.176) (P < 0.05). Coronal parameters such as CA, CI, CDD, and TA also showed weak correlation with clinical parameters (r = 0.137-0.202) (P < 0.05). Multiple regression analysis identified CA, CI, CDD, and PI-LL to be correlated with clinical parameters. On analysis for clinical outcomes (surgical rates and patient self-reported disability) along the grades of the SRS-Schwab sagittal modifiers, PT and SVA were not related to higher surgical rates or disability. CONCLUSION: Even though some radiological parameters showed statistically significant results, correlation between radiological and clinical parameters was weak. Not only deformity but also other clinical factors should be considered when evaluating DLS. LEVEL OF EVIDENCE: 4.

Centroid neural network with a divergence measure for GPDF data clustering.

An unsupervised competitive neural network for efficient clustering of Gaussian probability density function (GPDF) data of continuous density hidden Markov models (CDHMMs) is proposed in this paper. The proposed unsupervised competitive neural network, called the divergence-based centroid neural network (DCNN), employs the divergence measure as its distance measure and utilizes the statistical characteristics of observation densities in the HMM for speech recognition problems. While the conventional clustering algorithms used for the vector quantization (VQ) codebook design utilize only the mean values of the observation densities in the HMM, the proposed DCNN utilizes both the mean and the covariance values. When compared with other conventional unsupervised neural networks, the DCNN successfully allocates more code vectors to the regions where GPDF data are densely distributed while it allocates fewer code vectors to the regions where GPDF data are sparsely distributed. When applied to Korean monophone recognition problems as a tool to reduce the size of the codebook, the DCNN reduced the number of GPDFs used for code vectors by 65.3% while preserving recognition accuracy. Experimental results with a divergence-based k-means algorithm and a divergence-based self-organizing map algorithm are also presented in this paper for a performance comparison.

Recovery of image blocks using the method of alternating projections.

A technique for block-loss restoration in block-based image and video coding, dubbed recovery of image blocks using the method of alternating projections (RIBMAP), is developed. The algorithm is based on orthogonal projections onto constraint sets in a Hilbert space. For the recovery of a linear dimension N size block, a total of 8N vectors are extracted from the surrounding area of an N x N missing block. These vectors form a library from which the best matching spatial information for the missing block is extracted. Recovery vectors, including both undamaged and restored damaged pixels, are introduced. The vectors are used to find highly correlated information relating to the lost pixels. To assure continuity with the surrounding undamaged area, three additional convex constraints are formulated. Adherance to these sets is imposed using alternating projections. Simulation results using orthogonal projections demonstrate that RIBMAP recovers spatial structure faithfully. Simulation comparisons with other procedures are presented: Ancis and Giusto's hybrid edge-based average-median interpolation technique, Sun and Kwok's projections onto convex sets-based method, Hemami and Meng's interblock correlation interpolation approach, Shirani et al.'s modified interblock correlation interpolation scheme, and Alkachouh and Bellanger's fast discrete cosine transformation-based spatial domain interpolation algorithm. Characteristic of the results are those of the "Lena" JPEG image when one fourth of periodically spaced blocks in the image have errors. The peak signal-to-noise ratio of the restored image is 28.68, 29.99, 31.86, 31.69, 31.57, and 34.65 dB using that of Ancis and Giusto, Sun and Kwok, Hemami and Meng, Shirani et al., Alkachouh and Bellanger, and RIPMAP, respectively.

Content-based adaptive spatio-temporal methods for MPEG repair.

Block loss and propagation error due to cell loss or missing packet information during the transmission over lossy networks can cause severe degradation of block and predictive-based video coding. Herein, new fast spatial and temporal methods are presented for block loss recovery. In the spatial algorithm, missing block recovery and edge extention are performed by pixel replacement based on range constraints imposed by surrounding neighborhood edge information and structure. In the temporal algorithm, an adaptive temporal correlation method is proposed for motion vector (MV) recovery. Parameters for the temporal correlation measurement are adaptively changed in accordance to surrounding edge information of a missing macroblock (MB). The temporal technique utilizes pixels in the reference frame as well as surrounding pixels of the lost block. Spatial motion compensation is applied after MV recovery when the reference frame does not have sufficient information for lost MB restoration. Simulations demonstrate that the proposed algorithms recover image information reliably using both spatial and temporal restoration. We compare the proposed algorithm with other procedures with consistently favorable results.

Complex-bilinear recurrent neural network for equalization of a digital satellite channel.

Equalization of satellite communication using complex-bilinear recurrent neural network (C-BLRNN) is proposed. Since the BLRNN is based on the bilinear polynomial, it can be used in modeling highly nonlinear systems with time-series characteristics more effectively than multilayer perceptron type neural networks (MLPNN). The BLRNN is first expanded to its complex value version (C-BLRNN) for dealing with the complex input values in the paper. C-BLRNN is then applied to equalization of a digital satellite communication channel for M-PSK and QAM, which has severe nonlinearity with memory due to traveling wave tube amplifier (TWTA). The proposed C-BLRNN equalizer for a channel model is compared with the currently used Volterra filter equalizer or decision feedback equalizer (DFE), and conventional complex-MLPNN equalizer. The results show that the proposed C-BLRNN equalizer gives very favorable results in both the MSE and BER criteria over Volterra filter equalizer, DFE, and complex-MLPNN equalizer.