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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.

Mobile applications have grown rapidly in size. This dramatic increases in size and complexity make mobile applications less accessible to a broader scope of users. The prevailing approach for better accessibility of mobile applications is to manually reimplement slimmed versions with a small but representative portion of a regular original app. Unfortunately, this approach imposes significant burden on developers. We propose a system called Madusa to enable developers to effectively customize and reduce their mobile applications for Android. Madusa takes as input an original app, an upper bound on the size of a reduced version, and usage scenarios as a high-level specification of its desired core functionality. The output is a reduced version of the app that is still correct with respect to the specification while not exceeding the size limit. Madusa constructs a graph representing dependencies among methods and resources and identifies a sub-part of the graph using integer linear programming to generate a reduced version that exhibits behaviors as similar as possible to the original app. Our experimental evaluation on a suite of 19 Android apps available on Google Play Store. Madusa effectively converges to the desired simplified apps by reducing the app size by 40% on average (maximally by 60%). We conclude our approach effectively removes redundant code and resources with respect to given usage scenarios.

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.

Objective To evaluate the effectiveness and long-term outcome predictors of percutaneous sacroplasty (PSP). Methods This single-center study assessed 40 patients with sacral insufficiency fractures using the short-axis technique under C-arm flat-panel detector computed tomography (CT). Two radiologists reviewed the patients' magnetic resonance and CT images to obtain imaging findings before PSP and determine technical success, respectively. The short-term outcomes were visual analog scale score changes and opioid usage reductions. Long-term outcomes were determined using telephone interviews and the North American Spine Society (NASS) patient-satisfaction index at least one year after PSP. Results Technical success was achieved without any significant complications in 39 patients (97.5%). Telephone interviews were possible with 12 patients and failed in 10 patients; death was confirmed in 18 patients. Fifteen patients (50%) re-visited the hospital and received conservative treatment, including spinal injections. Nine patients reported positive satisfaction (NASS patient-satisfaction index 1 or 2), while the negative satisfaction group (NASS patient-satisfaction index 3 or 4, n=3) showed a higher incidence of compression fractures at the thoracolumbar spine level (66.7% vs. 22.2%) and previous spinal injection history (66.7% vs. 33.3%). The poor response group also showed higher incidences of facet joint arthrosis (100% vs. 55.6%), central canal stenosis (100% vs. 22.2%), neural foraminal stenosis (33.3% vs. 22.2%), scoliosis (100% vs. 33.3%), and sagittal malalignment (100% vs. 44.4%). Conclusion PSP was effective for sacral insufficiency fractures and showed good long-term outcomes. Combined compression fractures in the thoracolumbar spine and degenerative lumbar pathologies could be possible poor outcome predictors.

The etching properties of four types of transparent ceramics: sapphire (a single crystalline α-Al2O3), γ-AlON (γ-aluminum oxynitride), Mg-spinel (MgAl2O4), and Y2O3, as well as a polycrystalline opaque Al2O3 were examined using an inductively coupled plasma etcher under an incident plasma power of 2,000 W for up to 3 h. The transparent γ-AlON and opaque Al2O3 showed significant surface morphological changes, whereas sapphire, Mg-spinel, and Y2O3 revealed a relatively smooth surface upon etching. However, direct correlation between the surface morphological change and the degree of etching could not be drawn because sapphire showed a uniform surface etching despite its significant mass loss. Even though Y2O3 was found to be more plasma-resistant than Al2O3, overall, Mg-spinel was the most feasible transparent material for monitoring window application in a semiconductor processing chamber because of its minimal degree of erosion (≤0.4g/m2) and the transmittance change (≤2%) upon 3 h of fluorocarbon (CF4) plasma etching.

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

Kim, N.-G. and Lee, J.-H., 2021. Improvement of the qualification system for lifeguards. In: Lee, J.L.; Suh, K.-S.; Lee, B.; Shin, S., and Lee, J. (eds.), Crisis and Integrated Management for Coastal and Marine Safety. Journal of Coastal Research, Special Issue No. 114, pp. 628–632. Coconut Creek (Florida), ISSN 0749-0208. The purpose of this study is to propose improvement measures for the training and evaluation problems along with institutional problems of the lifeguard qualification system in Korea. To this end, a literature research was conducted on the qualification system along with previous domestic and overseas studies, and the Delphi method was used twice on 20 water safety experts. Consequently, first, the following priorities were proposed as an improvement plan for lifeguard training and evaluation: the reinforcement of the evaluation criteria of the equipment-based rescue to improve the rescue efficiency as the first priority, strengthening of the training and evaluation centered on the professional rescue techniques as the second priority, establishment of standardized training guidelines and evaluation indicators through exchanges among the 13 lifeguard educational institutions as the third priority, introduction of training and evaluation using specialized equipment in the field of first aid as the fourth priority, introduction of the marine practice after obtaining the qualification as the fifth priority, introduction of the evaluation method considering the environmental characteristics as the sixth priority, and introduction of the physical fitness test as the seventh priority. Second, the following priorities were proposed for improving the lifeguard system: the reorganization of the qualification system through integration with national lifeguard and establishment of a lifeguard qualification system monitoring institution as the first and second priorities, respectively, reinforcement of the pre-assessment system prior to participation in the qualification course as the third priority, the selection of the National Competency Standards (NCS) occupational group of the lifeguards as the fourth priority, annual re-evaluation of the educational institutions as the fifth priority, and confirmation of compliance with the training course by the educational institutions as the sixth priority.

We validate a coupled flow-geomechanics simulator for gas hydrate deposits, named T+M A M , performing two meter-scale laboratory experiments of gas hydrates for production by depressurization, replicating the gas hydrate deposit in the Ulleung Basin, East Sea, South Korea. The first experiment with a sand-only specimen is a 1D 1 m-scale depressurization test based on the excess gas method, which represents the grain coating hydrate growth. On the other hand, the second is a 3D 1.5 m-scale test with the excess water method for a sand–mud alternating layer system, representing the pore filling hydrate growth. We measure production and displacement at the top with different depressurization levels. In particular, the 3D test exhibits high coupling strength of substantial deformation induced by incompressibility of water and high deformability of the specimen. For validation, we match pressure, flow rate, and displacement between the experimental data and numerical results. Thus, we identify that T+M A M is a reliable simulator, which can be applied to fields in both permafrost and deep oceanic hydrate deposits of strongly coupled flow and geomechanics systems. This validation also implies that other coupled simulators based on the same coupling formulation as T+M A M can be validated when individual flow and geomechanics simulators are stable and reliable.

A new multi-layered design of joining filler, consisting of a Ti 3 SiC 2 layer and an in-situ reaction TiC transition layer, was proposed to join monolithic SiC. The robust TiC transition layer was formed in-situ by controlling the interface reaction and diffusion process between the deposited Ti layer and the SiC matrix. The joining process was evaluated by the analysis of the interface reaction, phase evolution, mechanical properties, and finite element analysis. The bending strength of the sample joined at 1500 °C was 155.8 ± 23.1 MPa, which was similar to that of the reference unjoined SiC (155.1 ± 35.6 MPa). The thermal residual stresses between SiC and Ti 3 SiC 2 were released by the formation of gradient layer of TiC at the interface. When the optimized joining approach was used, a dense TiC transition layer was formed and all brittle Ti-Si intermetallic phases completely transformed to Ti 3 SiC 2 . Furthermore, the proposed multi-layer joining design shows its potential to be used for joining of SiC-based ceramic matrix composites.

Jeong, Y.M.; Kim, S.G.; Lee, J.H.; Yoon, J.S., and Lee, W.D., 2017. Understanding characteristics of upward and downward flows in coral reef region for safety of recreational diving. In: Lee, J.L.; Griffiths, T.; Lotan, A.; Suh, K.-S., and Lee, J. (eds.), The 2nd International Water Safety Symposium. Journal of Coastal Research, Special Issue No. 79, pp. 35–39. Coconut Creek (Florida), ISSN 0749-0208. The goal of this study is to gain an understanding of the flow characteristics in reef regions through numerical simulations for safe recreational diving in the region. The applied numerical model was first validated to verify its feasibility and validity for carrying out the numerical simulations. Subsequently, an underwater survey was conducted in the Visayan Islands in the Philippines to model the reef region. Based on the underwater survey results, simulations were conducted in a three dimensional numerical wave tank with a model coral island. According to the numerical analysis results, stronge...

Kim, K.B.; Lee, J.H.; Kim, S.G.; Seok, K.H., and Choi, Y.S., 2017. Improvement plan on marine lifesaving educational course in Korea: Comparison with the status of the foreign marine leisure safety education groups. In: Lee, J.L.; Griffiths, T.; Lotan, A.; Suh, K.-S., and Lee, J. (eds.), The 2nd International Water Safety Symposium. Journal of Coastal Research, Special Issue No. 79, pp. 26–29. Coconut Creek (Florida), ISSN 0749-0208. The objective of this study is to identify the current status of qualification system of life guard in Korea and to suggest objective developmental plans according to domestic circumstances through qualification systems in Japan, Canada, and Finland. It is required to provide reliable education system by unifying the life-guard education courses in each education provider. The Life-guard educationl based on locational and environmental factors should be more sub-divided and standardized in advanced programs in the same manner as life-guard education system in member ...

A novel family of Ti3C2Tx/ferrite composites with high reflection loss was developed using a facile in situ co-precipitation method. The as-synthesized Ti3C2Tx/ferrite composite with a 5 wt% Ti3C2Tx MXenes loading exhibited high reflection loss (−42.5 dB) at 13.5 GHz. The effective absorption bandwidth of the 5 wt% Ti3C2Tx/Ni0.5Zn0.5Fe2O4 composite reached ∼3 GHz (12–15 GHz) in the K-band. The incorporation of Ti3C2Tx MXenes improved the electromagnetic impedance of the Ti3C2Tx/Ni0.5Zn0.5Fe2O4 composite resulting from the enhanced electrical conductivity. The potential electromagnetic wave absorption mechanisms were revealed, which may contain magnetic loss, dielectric loss, conductivity loss, multiple reflections, and scattering. The technique is facile, fast, scalable, and favorable for the commercialization of this composite. This study provides a potential way to develop EM wave absorbing materials for a large family of MXenes/ferrite composites.

The purpose of the present study was to investigate the characteristics of growth disturbances in patients with remaining growth after transphyseal anterior cruciate ligament (ACL) reconstruction who were confirmed to have no definite postoperative physeal abnormalities on magnetic resonance imaging (MRI). Forty adolescents (mean age 15.6 ± 1.0 years [range 12.2–16.8], mean follow-up 2.7 ± 0.7 years [range 2.0–5.5 years]), who underwent transphyseal ACL reconstruction and were confirmed to have no focal physeal disruptions on follow-up MRIs 6 to 12 months after the operation, were retrospectively evaluated. The patients were grouped according to the leg-length growth of the uninjured side, measured on scanograms, obtained before surgery, and at the final follow-up. Leg-length discrepancies (LLD) at the last follow-up were greater in patients with leg growth ≥4 cm than in those with leg growth

This paper uses a standard non-cooperative sequential game with two homogeneous players to analyze investment options of groundwater development project in South Korea’s Jeju island. The model is constructed as an option game taking the uncertainty of water price and the irreversibility of investment into account. The results show that the threshold water price of follower increases with the investment scale of both the leader and the follower while the threshold water price for the leader decreases as the investment scale of the leader increases. This makes the leader choose strategies to maximize the amount of groundwater extraction regardless of the follower’s strategy. Based on the results, it is recommended for policymakers to manage sustainable use of groundwater based on the policy measures such as the groundwater extraction quota system.

A technique for improving estimation accuracy is introduced in order to locate the impact position of artillery shell during the weapon scoring test. Study on localization of impacts using acoustic measurement has been conducted and the usability of sensor array is verified with experiments. When the blast occurs above the ground in the firing range, the acoustic sensor above the ground can measure the directly propagated sound with the ground-reflected one. In this study, a method for reducing estimation error by using the reflection signal measurements based on the time difference of arrival method. Considering the reflection sound works as same as placing a virtual sensor symmetrically through the ground. This idea enables a virtual three-dimensional array configuration with a two-dimensional plane array above the ground as such. The time difference between the direct and the reflected propagations can be estimated using cepstrum analysis. Performance test has been made in the simulation experiment in the football size area.

This paper presents an application of an optimal smoothing filter for moving target tracking problem based on measured noise source. In order to measure distance and velocity for the moving target, a beamforming method is applied to use the noise source by using microphone array. Also a Kalman filter and an optimal smoothing algorithm are adopted to improve accuracy of trajectory estimation by using a Singer target model. The simulation is conducted with a missile dynamics to verify performance of the optimal smoothing filter, and a model rocket is used for experiment environment to compare the trajectory estimation results between the beamforming, the Kalman filter, and the smoother. The Kalman filter results show better tracking performance than the beamforming technique, and the estimation results of the optimal smoother outperform the Kalman filter in terms of trajectory accuracy in the experiment results.

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.

Conditionally specified statistical models are frequently constructed from conditional one-parameter exponential family distributions. One way to formulate such a model is to specify the dependence structure among random variables through the use of a Markov random field. When this is done, a common assumption is that dependence is expressed only through pairs of random variables, the 'pairwise-only dependence' assumption. Using a Markov random field structure and the pairwise-only dependence assumption, Besag (1974) formulated exponential family 'auto-models', and showed the form that conditional one-parameter exponential family densities must have in such models. We extend those results under relaxation of the pairwise-only dependence assumption, and give a necessary form for conditional one-parameter exponential family densities under more general conditions of multiway dependence.

Introduction. Functional dyspepsia (FD) is a functional gastrointestinal disorder characterized by persistent upper dyspeptic symptoms without organic lesions. There is no standard therapy for FD. Yukgunja-tang (YGJT) is an herbal medicine used for treating upper gastrointestinal symptoms in Asia. Studies on the effect of YGJT on FD have been conducted. However, the results were inconsistent. In Hyungsang medicine, traditional Korean medicine, FD patients are classified into bladder body (BB) or gallbladder body (GB) subtypes by the shape and angle of their faces. Each subtype may have different characteristics, physiology, and pathology of the same disease. YGJT is more effective for patients with BB subtype. The three-dimensional facial shape diagnostic system (3-FSDS) was shown to be effective in diagnosing BB or GB subtypes. This study aimed to investigate the effect of YGJT on FD patients classified using the 3-FSDS. Materials and Methods. The current study was a placebo-controlled, double-blinded, randomized, two-center trial. Eligible patients were diagnosed with either BB or GB FD subtype using the 3-FSDS. Ninety-six participants (48 BB and 48 GB subtypes) were randomly allocated to treatment or control groups in a 2:1 ratio. YGJT or placebo was administered for eight weeks. The primary outcome was assessed using the total dyspepsia symptom scale (TDS), while the secondary outcomes were assessed using the single dyspepsia symptom scale (SDS), proportion of responders, visual analog scale, Nepean dyspepsia index, functional dyspepsia-related quality of life, and spleen qi deficiency questionnaire. Results and Discussion. The result of TDS showed the superior effect of YGJT on BB over GB subtype. The subgroup analysis of TDS and SDS scores showed the superior effect of YGJT over placebo. Other outcome variables did not show any significant differences between groups. Conclusion. YGJT may be considered for FD patients diagnosed with BB subtype using 3-FSDS.

The purpose of this study was to find out how a canoe leader's revolutionary leadership affects his trust and how a leader's trust affects the organizational commitment. 350 participants were selected out of male and female registered as canoeists by the Korea Canoe Federation in 2011 through the random sampling. Except for 26 data with those not seriously taken, 324 responses were taken as valid samples. Frequency analysis, reliability analysis, factor analysis, correlation analysis, and multi-regression analysis have been conducted. The conclusion is as follows: First, a leader's revolutionary leadership positively affects his trust. Secondly, a leader's revolutionary leadership has a positive effect on his organizational commitment. Lastly, a leader's trust positively affect the organizational commitment.

Ni-Carbon nanotube (CNT)-Ni0.5Zn0.5Fe2O4 multiphase composites were successfully prepared using microwave sintering (MWS) and spark plasma sintering (SPS) techniques. The obtained samples were characterized by scanning electron microscopy, electrical conductivity, and physical properties measurement system with vibrating sample magnetometer. The SPS prepared composites exhibited higher density, fine grain size, and to maintain favorable three-dimensional conductive network of CNTs compared with the microwave sintered (MWS) ones. Whether use MWS or SPS, both the density and the grain size are increasing with the CNTcontent increment. The increasing of density and grain size is the main contribution of the saturation magnetization increasing. In the composites of high content of CNTs (such as 5wt%), the spinel structure of ferrite was totally destroyed, as indicated by a considerable decrease in the saturation magnetization. Interestingly, it is found that the Curie temperature increases with the increment of CNT content while the high saturation magnetization was maintained, which has implication that the multiphase ferrite composites will find application in a broad temperature range. (C) 2014 The Ceramic Society of Japan. All rights reserved.

Ni-Carbon nanotube (CNT)-Ni0.5Zn0.5Fe2O4 multiphase composites were sintered by spark plasma sintering (SPS) technique. Ni nanoparticles were in-situ formed due to the localized carbothermal reduction by CNTs and well distributed between grain boundaries in the composites. The electrical conductivity of the resultant multiphase composites was strongly dependent on the weight percentage of CNTs. In the SPS process, CNTs acted as "heating source" and improved the consolidation of the composites. The results indicate that the introduction of the CNTs can promote the sintering kinetics of the ferrite ceramics. However, the grain growth kinetics has been inhibited by SPS and the grain size becomes finer. (C) 2014 The Ceramic Society of Japan. All rights reserved.