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Abstract Background The purpose of this study was to find the factors influencing successful bone union for isolated subtalar arthrodesis in posttraumatic subtalar arthritis following calcaneal fracture. Material and methods We retrospectively analyzed the rate of successful bone union of 119 cases of isolated subtalar arthrodesis for posttraumatic subtalar arthritis performed at five university hospitals between January 2010 and December 2019. Multivariate logistic regression analysis was used to find the factors associated with successful bone union. Successful bone union was defined as resolution of hindfoot pain with the presence of osseous trabecular bridging involving more than 50% of the posterior facet within 6 months postoperatively. Results There were 77 (64.7%) cases of successful bone union, 11 (9.2%) cases of delayed union, 8 (6.7%) cases of questionable union, and 23 (19.3%) cases of nonunion. Use of fully threaded screws was 5.90 times [odds ratio (OR) = 5.90, 95% confidence interval (CI) = 1.42–24.49, p = 0.02] more likely to achieve successful bone union compared to the use of partially threaded screws. Use of two parallel screws or the two divergent screws were 3.71 times (OR = 3.71, 95% CI = 1.05–13.14, p = 0.04) and 4.65 times (OR = 4.65, 95% CI = 1.23–17.53, p = 0.02) more likely to achieve successful bone union compared to the use of a single screw. Use of cancellous autograft or structural autograft was 4.72 times (OR = 4.72, 95% CI = 1.17–19.06, p = 0.03) and 7.12 times (OR = 7.12, 95% CI = 1.46–34.68, p = 0.02) more likely to achieve successful bone union compared to no graft use. Conclusion Use of fully threaded screws, autograft, and two screws compared to a single screw were the factors associated with successful bone union within six postoperative months after subtalar arthrodesis for the posttraumatic arthritis.

Accurate battery state-of-charge (SOC) estimation is important for the efficient and reliable operation of battery application systems. The extended Kalman filter (EKF), which is based on the battery model, is widely used as a real-time SOC estimation algorithm; furthermore, its accuracy depends on the model accuracy. However, the conventional EKF uses one value for each battery parameter ( $R_{i}$ , $R_{d}$ and $C_{d}$ ) regardless of the SOC, even though their values change according to the SOC. To address this problem, this study proposes an improved EKF that applies battery parameters that change according to the SOC of a battery model. In the proposed method, the entire SOC was divided into several sections considering the deviation of the parameter values according to the SOC. Subsequently, the average values for each SOC Section were calculated, and the values of the battery parameters were updated with the average values according to the SOC. To verify the performance of the proposed EKF, the parameters of commercial Li-ion batteries were extracted with dis-charge currents of 1C- and 2C-rates at ambient temperatures of 0 °C, 25 °C, and 45 °C, and MATLAB simulations were performed. Compared to the conventional EKF, the proposed EKF estimated the SOC more accurately under all the simulation conditions. Compared to the conventional EKF, the maximum reduced root-mean-square error and maximum error of the proposed method were 49.37% and 56.41%, respectively.

Objective To compare the parameters associated with the normal ankle syndesmosis between the hindfoot alignment view (HAV) and anteroposterior (AP) view and determine which view is more accurate for comparing the left and right ankles. Methods This study involved 61 subjects without syndesmosis injury who had radiographs of both ankles. The tibiofibular clear space (TFCS), tibiofibular overlap (TFO), and medial clear space (MCS) were measured in each view. Intraclass correlation coefficients were used to assess the agreement between the two ankles. Difference ratios for the measured parameters between the ankles were also compared. Results The agreement for TFCS showed wide disparity between the two ankles (AP view, 0.576; HAV, 0.858). The highest degree of agreement was seen for TFO (AP view, 0.733; HAV, 0.926). The agreement for MCS was low in both groups. The mean difference ratio for TFCS was also lower in the HAV group (9.9%) than in the AP view group (16.4%); a similar result was observed for TFO (16.4% vs. 25.8%). Conclusions For evaluation of the syndesmosis, use of the HAV showed increased accuracy and few measurement errors when comparing the left and right ankles relative to use of the AP view.

Abstract High strength SiC whisker-reinforced Ti3SiC2 composites (SiCw/Ti3SiC2) with an improved thermal conductivity and mechanical properties were fabricated by spark plasma sintering. The bending strength of 10 wt% SiCw/Ti3SiC2 was 635 MPa, which was approximately 50% higher than that of the monolithic Ti3SiC2 (428 MPa). The Vickers hardness and thermal conductivity (k) also increased by 36% and 25%, respectively, from the monolithic Ti3SiC2 by the incorporation of 10 wt% SiCw. This remarkable improvement both in mechanical and thermal properties was attributed to the fine-grained uniform composite microstructure along with the effects of incorporated SiCw. The SiCw/Ti3SiC2 can be a feasible candidate for the in-core structural application in nuclear reactors due to the excellent mechanical and thermal properties.

Nowadays, the steady-state somatosensory evoked potential (SSSEP)-based brain-computer interfaces (BCIs) has been developed for improving the quality of daily life for people with physical disabilities. However, due to its poor performance of recognizing selective attention tasks and inattention(rest)-state, the SSSEP-based BCI has not been widely used for practical interfaces. In this paper, we propose a mutual information-based spatio-spectral feature selection method for recognizing selective attention tasks and inattention(rest)-state using dry electrodes considering a real-life application, when vibration stimuli were applied to both index fingers. In our methods, the filter-bank common spatial pattern (FBCSP) was used for extracting spatio-spectral features of the SSSEP. Then, discriminative features were selected using a mutual information-based best individual feature (MIBIF) algorithm. The regularized linear discriminant analysis (RLDA) used as the classifier. The feasibility of the proposed method was demonstrated through eight healthy subjects using the vibration stimuli induced SSSEP with spatially clear and distinguishable patterns for SSSEP-based BCI. From our study, the proposed method showed the best classification accuracy with a kappa value of 0.35±0.17. Furthermore, based on the ANOVA with posthoc tests, the proposed method showed significantly higher accuracy as 57.9% in decoding three classes (p -value

Automated driving technologies have advanced remarkably and are expected to be a part of our lives soon. Because automated driving technology does not require a driver, a significant change in future mobility services is expected. Automated driving technology is closely related to the development of public transit services as it can significantly reduce driver labor costs and provide a more comfortable in-vehicle environment. In particular, the preference for automated mobility-on-demand services that can respond in real time to the dynamic demand through automated driving technology is growing. Previous studies have compared passengers’ preferences for automated mobility-on-demand services and other transportation modes and proposed a way to enable more passengers to use automated mobility-on-demand services. However, as the number of pilot operations increases, future research will focus on ways to improve competitiveness among automated mobility-on-demand services. This study conducts a passenger preference survey based on the characteristics of automated mobility-on-demand services. In particular, changes in the in-vehicle environment and seat selection system, which differ from existing mobility-on-demand services due to automated driving technology, are investigated. The latent class modeling approach is used to classify passengers based on stated preference data collected from the survey. The estimation results show that vehicle type and seat choice system have a significant impact on passengers’ preference for automated mobility-on-demand services. In addition, considering that a high percentage of passengers do not prefer to improve autonomy in seat reservation and the in-vehicle environment, this study suggests that cost-consuming service improvement strategies are not always appropriate.

Deep learning approaches are widely employed for forecasting short-term travel demand to respond to real-time demand. Although it is critical for demand forecasting to be evenly distributed in the spatial and temporal views to support real-time mobility service operations, in related studies, the predictive performance of models has been evaluated only in terms of aggregated errors. Therefore, the present study was conducted to investigate the distribution of errors to explore spatiotemporal correlations. Six deep learning models with the same architecture, except for the base module, consisting of three stacked layers, were constructed. These models were used to forecast demands for a station-based bike-sharing service in Seoul, South Korea. To attain our goals, global and local Moran’s I of the errors was introduced to evaluate the spatial and temporal performances of the deep learning approaches. The results showed that the model with convolutional long short-term memory layers, which are effective at predicting spatiotemporal data, outperformed the other models in terms of aggregated performance. However, the global Moran’s I of the errors in the model reflects spatial dependency over the regions. This suggests that the best predictive performance of the model does not necessarily imply that it performs well in demand forecasting in all regions. Furthermore, cluster and outlier analyses of the errors indicated that excessive or insufficient predictions were clustered or dispersed throughout the regions. These results can be used to enhance the model by introducing the spatial correlation index into the loss function or by incorporating additional features for handling spatial correlations.

Unintended acceleration car accident which is hard to be regarded as human errors is examined. We investigated the accident car to determine the cause upon being requested to investigate by the police. From the car black box, we could narrow down the reason of the acceleration. As one of the causes of unintended acceleration we assumed that the restoration failure of the pedal interfered with by improper use of a floor mat and could reconstruct this. We discussed the acceleration values ​​of the accident vehicle and paid attention to the floor mat used in it. The results indicate that the negligible physical interference in the accelerator linkage could cause a devastating accident.

Category: Trauma; Ankle Introduction/Purpose: Isolated lateral malleolus fracture is one of the most common fractures. However, there is controversy regarding the rehabilitation protocols used after surgery. In particular, the initiation point for the weight bearing has not been standardized. In the present study, we investigated the prognostic difference between the immediate and delayed weight bearing on isolated lateral malleolus fractures. Methods: Retrospectively, the medical records of matched 50 and 41patients in the immediate and delayed weight-bearing groups were reviewed. All patients were treated with open reduction and internal fixation using an anatomical locking compression plate. In the immediate weight-bearing group (IWB), tolerable weight bearing (i.e., that can be endured immediately after surgery with crutches) was permitted. In the delayed weight-bearing group (DWB), weight bearing was completely restricted for 4 weeks after surgery. Ankle motion exercise were permitted in both groups since postoperative day. Radiographic assessment data and the clinical outcomes were reviewed. Results: There were no significant differences noted in the radiographic assessments and complications between the two groups. Significant differences of shortening the return to work and hospital stays of IWB rehabilitation protocol were confirmed(5.7 vs. 8.0 days, 6.0 vs. 8.0 days in the IBW and DWB groups, respectively). In FAOS, there was a significant difference in the sport factor evaluated at postoperative 3 months(75.5 vs 68.5, respectively). Conclusion: There were no significant differences between the two groups in the postoperative radiological outcome and complications. And benefits of shortening the return to work and hospital stays of IWB rehabilitation protocol were confirmed. Conclusively, immediate weight bearing is recommended in patients with isolated lateral malleolus fracture, following anatomical reduction and firm fixation through surgery.

Category: Ankle; Sports; Trauma Introduction/Purpose: There are numerous studies recommending fibular groove deepening in the surgical treatment of peroneal tendon dislocation; however, there are some disadvantages to fibular groove deepening procedures. In this study, we evaluated the results of anatomic reattachment of the peroneal retinaculum without fibular groove deepening as a treatment for traumatic peroneal tendon dislocation. Methods: Thirty six patients with recurrent peroneal tendon dislocation, who underwent retinaculum repair without a fibular groove deepening procedure performed by two surgeons between March 2004 and March 2017, were enrolled in this study. Resubluxation of tendon, pain on inversion and eversion power of the ankle were monitored. The range of motion of inversion and eversion were measured and then compared to that of the contralateral side. AOFAS, VAS, FFI scores were obtained for all patients preoperatively and at the final follow-up. Postoperative complications such as infection, sural nerve injury, and recurrence were monitored. Results: Thirty four patients fully recovered without resubluxation of tendon. Two patients were injured again while playing soccer 6 months after the surgery and fast running 20 months after the surgery respectively. One patient had sural nerve injury. But the symptom was relieved at 6 months after the surgery. None of the patients had weakness of evertor. None of the patients had limited ankle motion. Mean AOFAS, VAS, FFI score improved significantly. Conclusion: In conclusion, for the treatment of recurrent dislocation of the peroneal tendon reattachment of the superior retinaculum only without groove deepening followed by proper rehabilitation is sufficient.

Neuroblastoma is a malignant tumor usually occurring in children, which most commonly develops in the abdomen. Primary cervical neuroblastoma has rarely been reported. We present a case of primary retropharyngeal neuroblastoma with an ipsilateral lymph node metastasis, manifesting as a growing neck mass in the retropharyngeal space, in an 11-month old infant.

Mesenteric fibromatosis is a rare benign fibroblastic tumor; moreover, cases that occur in the mesocolon are even rarer. In some cases, mesenteric fibromatosis is difficult to differentiate from a malignant tumor that shows an infiltrative growth pattern or forms intussusception similar to lymphoma or adenocarcinoma. In this study, we reported a case of mesenteric fibromatosis represented as a colo-colic type intussusception adjacent to the ascending colon mimicking malignant tumors such as lymphoma or adenocarcinoma.

Traditionally, adult intussusception has required a bowel resection because of the malignancy risk. A patient with anorexia, weight loss, and abdominal pain visited our clinic. A physical exam and imaging study revealed no acute peritoneal signs. A colonoscopy for biopsy and bowel reduction was attempted. The tissue sample was consistent with intestinal tuberculosis. We report intestinal tuberculosis complicating intussusception which was treated without surgical intervention.

In this paper, an innovative modeling approach for Li-ion battery packs is proposed by considering intrinsic cell unbalances and packaging elements. The proposed modeling method shows that the accurate battery pack model can be achieved if the overall influences of intrinsic cell unbalances and packaging elements are taken account. Concurrently, the proposed method takes a practical model structure, resulting in the reduction of computational burden in a battery management system. Furthermore, because the proposed method utilizes cell information without a manufactured battery pack, it can be helpful to design optimal battery packs. The proposed method is verified through simulation and experimental results of the Li-ion battery pack along with the battery cycler. In three test profiles, the mean absolute percentage errors and root mean square errors of the proposed pack model do not exceed 0.5% and 0.07 V, respectively.