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Objectives: Vestibular epilepsy refers to epilepsy in which vertigo is the sole or main symptom of a seizure. However, epilepsy is rarely considered as a differential diagnosis in patients complaining of dizziness. Here, we reviewed ten cases of vestibular epilepsy and analyzed the dizziness complained by the patient.Methods: In this study, the medical records of dizziness patients with epileptic discharges observed on electroencephalogram were retrospectively analyzed. Patients who had other obvious causes of dizziness, lacked a description of dizziness, or were not taking antiseizure medications were excluded. We finally recruited 10 patients, and investigated their dizziness characteristic, brain imaging tests, electroencephalograms, and blood test findings.Results: Patients with vestibular epilepsy usually felt dizzy abruptly while not moving, and often complained of dizziness in the form of spinning around or becoming dazed. Dizziness was short, usually between a few seconds and a few minutes, and the frequency of occurrence was variable, so there was no consistent trend. There were no abnormal findings in blood tests. In brain imaging test, most patients did not show significant abnormalities. The electroencephalographic abnormalities of the patients were mainly observed in the temporal lobe, and the dizziness they complained of improved when they started taking antiseizure medications.Conclusions: If a patient with dizziness complains of dizziness that occurs suddenly and lasts for a short time, early electroencephalogram should be considered to prevent the diagnosis of epilepsy from being overlooked or delayed.

The incorporation of cadmium telluride (CdTe) nanowire photovoltaics offers the possibility to overcome energy loss in solar cells associated with minority carrier recombination, and to increase optical efficiency by reducing reflection. In this study, CdTe nanowires (NWs) were synthesized from individual nanoparticles encapsulated with thioglycolic acid (TGA) and 1-thioglycerol (TGC) via self-assembly under illumination by a 550 nm wavelength light. This wavelength resulted in the self-assembly of nanoparticles into nanowires. TGA-stabilized CdTe NWs (TGA-NWs) and TGC-stabilized CdTe NWs (TGC-NWs) that made up the self-assembly were different crystalline structures. Most of the produced nanowires were straight and varied in length from 1.2 to 3.9 µm. The oxidation of Te2− in CdTe nanoparticles under a 550 nm wavelength light resulted in the assembly of nanowires consisting of several layers of individual nanoparticles. Transmission electron microscopy was performed to characterize the synthesized nanostructures. Photoluminescence analysis showed that the wavelength of the nanostructures was slightly blue-shifted.

Background and Purpose Epidemiologic data suggest that cluster headache (CH) is significantly associated with cigarette smoking. The aim of this study was to determine differences in features between patients with a smoking history and those who are never-smokers, using data from a prospective multicenter registry. Methods Data used in this study were obtained from the Korean Cluster Headache Registry that collected data from consecutive patients diagnosed with CH. We compared clinical and demographic features between ever-smokers (current or former smokers) and never-smokers. Results This study enrolled 250 patients who were diagnosed with CH, of which 152 (60.8%) were ever-smokers and 98 (39.2%) were never-smokers. The age at CH onset was significantly lower in the never-smoker group than in the ever-smoker group [27.1±12.9 years vs. 30.6±10.9 years (mean±standard deviation), p=0.024]. Seasonal rhythmicity (58.1% vs. 44.7%, p=0.038) and triptan responsiveness (100% vs. 85.1%, p=0.001) were higher in never-smokers, while other clinical features such as pain severity, duration, attack frequency, and associated autonomic symptoms did not differ significantly between the groups. The male-to-female ratio was markedly higher in ever-smokers (29.4:1) than in never-smokers (1.7:1). Conclusions Most of the clinical features did not differ significantly between patients with a smoking history and never-smokers. However, the age at CH onset, sex ratio, and seasonal rhythmicity were significantly associated with smoking history.

Background Previous studies have reported notable differences in demographic and clinical features of cluster headache between Western and Asian populations, including lower prevalence of the chronic type and in women. Recently, prodromal symptoms of migraine and pre-attack symptoms of cluster headache have drawn attention regarding their potential pathophysiological implications and pre-emptive treatment. However, pre-attack symptoms of cluster headache have not been studied in the Asian population. Methods A total of 136 patients with cluster headache (21 first-onset, 110 episodic, and five chronic cases) were recruited in this multi-center study between October 2018 and December 2019. We evaluated the characteristics of pre-attack symptoms in a current bout using a structured questionnaire. Univariable and multivariable logistic regression analyses were performed to evaluate the factors associated with presence of pre-attack symptoms. Results Pre-attack symptoms were reported in 71.3% of our patients with cluster headache. When present, pre-attack symptoms occurred at a median of 20 minutes (range 1–120) before the attack. The prevalence of local and painful, local and painless sensory, autonomic, and general symptoms was 58.8%, 14.7%, 11.0%, and 30.1%, respectively. Multivariable logistic regression analysis revealed that higher number of bouts was associated with higher prevalence of pre-attack symptoms (OR = 1.464, p = 0.044). Conclusions Pre-attack symptoms were frequently observed in Korean patients with cluster headache, which was consistent with previous Western studies.

Background Contrary to pre-attack symptoms before an individual cluster headache attack, little is known about the pre-cluster symptoms before the onset of cluster bouts. We previously described pre-attack symptoms before cluster headache attacks. The aim of this study was to investigate characteristics of pre-cluster symptoms in patients with episodic cluster headache. Methods In this multicentre study, 184 patients with episodic cluster headache were recruited between October 2018 and December 2020. They were interviewed by investigators and completed a structured questionnaire. To investigate pre-cluster and pre-attack symptoms, we assessed 20 symptoms and signs using the questionnaire. Results The upcoming cluster bout was predictable in 35.3% (n = 65/184) of the patients. When present, pre-cluster symptoms occurred at a median duration of 7 days (interquartile range, 2.3–14 days) before the onset of the cluster bout. Patients with pre-cluster symptoms showed a higher proportion of women, prevalence of pre-attack symptoms and seasonal rhythmicity, frequency of cluster headache attacks per day, and total number of cluster bouts compared to patients without pre-cluster symptoms. In univariable and multivariable logistic regression analyses, female sex was associated with the predictability of pre-cluster symptoms (odds ratio = 2.297, p = 0.016). Conclusions The upcoming cluster bout was predicted in approximately 35% of patients with episodic cluster headache, which may allow for an earlier preventive treatment and help understand the pathophysiology.

The purpose of this study is to analyze the scope of the expected improvement effect of office buildings and educational research facilities according to green remodeling. Thus, in order to quantitatively grasp the architectural performance of the existing buildings, the building thermal performance, the airtightness, the indoor environment, and the air quality were measured using equipment. The analysis indicated that the envelope performance and the indoor environment were unsatisfactory compared to the current legal standards, and for indoor air quality, CO2 and formaldehyde were measured to be dissatisfactory in some buildings. The energy analysis results indicated that the improvement range differed according to the renovation history for each building, resulting in differences in the energy-saving rate for each alternative. The reduction rates of primary energy consumption using energy simulation were 38.5–67.4% for office buildings and 23.7–66.3% for educational research facilities, and the payback periods were 14 to 27 years for office buildings and 12 to 30 years for educational research facilities. These results are expected to contribute to the activation of green remodeling because they can be used as indicators to predict the expected construction cost, the payback period, and the expected effect required for green remodeling.

This study incorporated the social spider algorithm (SSA), which simulates the preying behaviors of a group of spiders, to explore energy-efficient train operations. In this SSA, the magnitude of the vibration signal transmitted by the prey on a simulated spider web was used to determine the location with the most abundant food, which was equivalent to the optimal solution for train acceleration. In addition, a random movement model was implemented in the SSA to facilitate its capability for both local and global search and thereby increase its probability in identifying the optimal solution. A railroad route in Taiwan was simulated to verify the feasibility of this approach; the simulated data were then compared with the measured data from the actual test. According to the measured data, the SSA can formulate feasible railroad energy conservation plans and can assist locomotive engineers in planning their train operations. The results of the SSA were also compared to those of the teaching–learning-based optimization, to validate the superiority of the SSA.

Background: Although cranial autonomic symptoms are typical in cluster headache, some individuals with cluster headache show no cranial autonomic symptoms during their headache attacks. Probable cluster headache is a subtype of cluster headache that fulfils all but one of the five criteria for cluster headache. This study aimed to investigate the frequency and clinical features of cluster headache and probable cluster headache without cranial autonomic symptoms in comparison to those with cranial autonomic symptoms.Methods: We analysed data from the Korea Cluster Headache Registry, a prospective multicentre registry involving data from 16 hospitals.Results: Of the 216 participants with cluster headache and 26 with probable cluster headache, 19 (8.8%) and 7 (26.9%), respectively, did not have cranial autonomic symptoms. Participants with cluster headache without cranial autonomic symptoms exhibited less severe anxiety (General Anxiety Disorder-7 score, median [interquartile range], 2.0 [1.0-6.0] vs 8.0 [3.0-12.0], p = 0.001) and depression (Patient Health Questionnaire-9 score, 3.0 [1.0-7.0] vs 7.0 [3.0-11.0], p = 0.042) than those with cranial autonomic symptoms. Other clinical features, including headache intensity, daily headache frequency, attack duration, bout duration, and location of the pain, did not differ between participants with cluster headache with and without cranial autonomic symptoms. Headache intensity was less severe in participants with probable cluster headache without cranial autonomic symptoms than in those with cranial autonomic symptoms (numeric rating scale, 8.0 [7.0-8.0] vs 9.5 [8.0-10.0], p = 0.015).Conclusions: A significant proportion of participants with cluster headache and probable cluster headache did not have cranial autonomic symptoms. Some clinical features of cluster headache and probable cluster headache differed based on the presence of cranial autonomic symptoms.

Background and purpose There have been few reports on recent trends in the occurrence of epilepsy. The aim of this study was to estimate the incidence and prevalence of epilepsy and analyze their annual trends in Korea over the period 2009-2017. Methods This nationwide population-based study was carried out using the National Health Insurance Service of Korea database. A prevalent case was defined as one of a patient receiving a prescription of anticonvulsants under the diagnostic codes for epilepsy or seizure. An incident case was ascertained by confirming the absence of any epilepsy-related diagnostic codes and anticonvulsant prescription for 2 years or more before the operational definition for a prevalent case was met. Alternative operational definitions for epilepsy were tested. The temporal trends of the incidence and prevalence of epilepsy were analyzed using a Poisson regression model, and are expressed as average annual percentage changes (AAPCs). Results The incidence of epilepsy increased from 28.7/100,000 persons in 2009 to 35.4/100,000 persons in 2017. The prevalence increased gradually from 3.4/1,000 persons in 2009 to 4.8/1,000 persons in 2017. These increasing trends were more evident among elderly subjects aged ≥75 years and in those who had codes for epilepsy or seizure as an additional diagnosis. Age standardization revealed a less prominent but still increasing trend in both incidence (AAPC=0.48%) and prevalence (AAPC=3.11%). Conclusions There have been increasing trends in both the prevalence and incidence of epilepsy in Korea between 2009 and 2017. This finding appears to be related to societal aging and the high incidence of symptomatic epilepsy in the elderly population.

Background Our aim was to investigate the relationship between coexisting cluster headache (CH) and migraine with anxiety and depression during active cluster bouts, and how symptoms change during remission. Methods We analyzed data from 222 consecutive CH patients and 99 age- and sex-matched controls using a prospective multicenter registry. Anxiety or depression was evaluated using the Generalized Anxiety Disorder-7 (GAD-7) or Patient Health Questionnaire-9 (PHQ-9), respectively. Moderate-to-severe anxiety or depression was defined as a score of ≥10 at baseline (during a cluster bout). We assessed for changes in anxiety and depression during CH remission periods. Results Among the CH patients, the prevalence of moderate-to-severe anxiety and depression was seen in 38.2% and 34.6%, respectively. Compared with controls, CH patients were associated with moderate-to-severe anxiety and depression (multivariable-adjusted odds ratio [aOR] = 7.32, 95% confidence intervals [CI] = 3.35–15.99 and aOR = 4.95, 95% CI = 2.32–10.57, respectively). CH patients with migraine were significantly more likely to have moderate-to-severe anxiety and depression (aOR = 32.53, 95% CI = 6.63–159.64 and aOR = 16.88, 95% CI = 4.16–68.38, respectively), compared to controls without migraine. The GAD-7 and PHQ-9 scores were significantly reduced between cluster bout and remission periods (from 6.8 ± 5.6 to 1.6 ± 2.8; P P Conclusions Our results indicate that CH patients are at increased risk of anxiety and depression, especially in the presence of coexisting migraine. However, the anxiety and depression can improve during remission periods.

Background and purpose The aim of this study was to survey the expert opinions on treatments for convulsive status epilepticus (CSE) and nonconvulsive status epilepticus (NCSE) in adults. Methods Forty-two South Korean epileptologists participated in this survey. They completed an online questionnaire regarding various patient scenarios and evaluated the appropriateness of medications used to treat CSE and NCSE. Results Initial treatment with a benzodiazepine (BZD) followed by either a second BZD or an antiepileptic drug (AED) monotherapy was the preferred treatment strategy. More than two-thirds of the experts used a second BZD when the first one failed, and consensus was reached for 84.8% of the survey items. The preferred BZD was intravenous (IV) lorazepam for the initial treatment of status epilepticus. IV fosphenytoin and IV levetiracetam were chosen for AED monotherapy after the failure of BZD. The treatments for NCSE were similar to those for CSE. Continuous IV midazolam infusion was the treatment of choice for iatrogenic coma in refractory CSE, but other AEDs were preferred over iatrogenic coma in refractory NCSE. Conclusions The results of this survey are consistent with previous guidelines, and can be cautiously applied in clinical practice when treating patients with CSE or NCSE.

Additional file 1: Table S1. Association of cluster headache and coexisting migraine with suicidal iedea of Patient Health Questionnaire-9.

Defining and measuring non-rigid or flexible parts has been controversial in industry for many years. There are two primary areas of controversy. The first is agreeing on what exactly a non-rigid part is. The second is agreeing on how to define and measure a non-rigid part. The subject of non-rigid parts is further complicated by the brief coverage it receives in the national and international standards. This leaves each company to improvise or create its own rules for non-rigid parts. There are some who believe that Geometrical Dimensioning and Tolerancing (GD&T) should not be used on non-rigid parts. This is not true. The ASME Y14.5M standard applies to rigid parts as a default condition. However, there is no definition given for a rigid part. The term rigid part has been used in industry for so long that it has gained a definition by its general use. When most people in industry say rigid part, they are referring to a part doesn’t move (deform or flex) when a force (including gravity) is applied. How much force is relative based on the part characteristics. In reality, all parts will deform (or flex) if enough force is applied. Using this logic, all parts would be considered non-rigid. However, we all know that this is not how parts are treated in industry. Although GD&T defaults to rigid parts, it should also be used on non-rigid parts with a few special techniques. Actually 50~60% of all products designed contain parts or features on parts that are non-rigid. Therefore, we try to suggest the definitions of rigid and non-rigid parts and method to measure non-rigid parts.

Objective The aim of this study was to gather the expert opinions of Korean epileptologists regarding the treatment of adult patients with epilepsy. Methods A total of 42 neurologists who specialized in epilepsy were surveyed. They completed an online questionnaire describing multiple patient scenarios. Using these scenarios, they evaluated treatment strategies and gave their preference for specific antiepileptic drugs (AEDs) used to treat genetically mediated generalized epilepsy and focal epilepsy. Results Initial AED monotherapy, followed by a second form of alternative monotherapy or an add-on combination therapy, was the preferred treatment strategy. The experts reached consensus for 87.2% of the items. The most commonly selected AEDs for the initial monotherapy for patients with generalized epilepsy were levetiracetam or valproate. For those with focal epilepsy, levetiracetam, oxcarbazepine, or lamotrigine were the most popular selections. Ethosuximide was the treatment of choice only for patients with generalized epilepsy with prominent absence seizures. Levetiracetam was preferred as an add-on therapy for both generalized and focal epilepsy. For special populations of patients, such as elderly adults or those with comorbid diseases, levetiracetam or lamotrigine was selected as the treatment of choice. Conclusion Most of the survey results were in accordance with the US expert opinion survey published in 2016. This survey can assist clinicians in making clinical decisions when treating individual adult patients with epilepsy.

Flexible pentacene-based organic thin-film transistors (TFTs) were fabricated and their performance was investigated as a function of the bending radius and the thickness of the polydimethylsiloxane (PDMS) encapsulation layer. The TFTs were fabricated on a flexible polyimide film (film thickness: 75 $\mu \text{m}$ ), and encapsulated by a PDMS layer. Degradation of the device performance during application of a tensile bending stress of 3 mm was minimized by utilizing an encapsulation layer thickness of 75 $\mu \text{m}$ , because the mechanical strain on the pentacene layer was almost off-set (tensile strain was applied to the bottom layer of the pentacene, and compressive strain was applied to the top layer of pentacene). At the tensile bending stress of 3 mm, the performance of the non-encapsulated TFT was degraded, whereas the encapsulated device showed great stability. This flexibility and bending stability were enabled by the use of the 75- $\mu \text{m}$ PDMS encapsulation layer, due to the location of the pentacene active layer in the neutral region position. A mechanical reliability test was performed for 120 min with a bending radius of 3 mm, demonstrating that only the device with the 75- $\mu \text{m}$ thick encapsulation layer showed stable device performance over a stress time of 120 min.

Purpose To compare controlled-release carbamazepine monotherapy (CBZ-CR) with lamotrigine and valproate combination therapy (LTG + VPA) in equivalent total drug load, as initial drug regimen in untreated patients with partial and/or generalized tonic-clonic seizures (GTCS). Methods This unblinded, randomized, 60-week superiority trial recruited patients having two or more unprovoked seizures with at least one seizure during previous three months. After randomization into CBZ-CR or LTG + VPA, patients entered into eight-week titration phase (TP), followed by 52-week maintenance phase (MP). Median doses of CBZ-CR and LTG + VPA were 600 mg/day and 75 mg/day + 500 mg/day, respectively. Primary outcome measure was completion rate (CR), a proportion of patients who have completed the 60-week study as planned. Secondary efficacy measures included seizure-free rate (SFR) for 52-week of MP and time to first seizure (TTFS) during MP. Results Among 207 randomized patients, 202 underwent outcome analysis (104 in CBZ-CR, 98 in LTG + VPA). CR was 62.5% in CBZ-CR and 65.3% in LTG + VPA (p = 0.678). SFR during MP was higher in LTG + VPA (64.1%) than CBZ-CR (47.8%) (P = 0.034). TTFS was shorter with CBZ-CR (p = 0.041). Incidence of adverse effects (AEs) were 57.7% in CBZ-CR and 60.2% in LTG + VPA and premature drug withdrawal rates due to AEs were 12.5% and 7.1%, respectively, which were not significantly different. Conclusion CR was comparable between LTG + VPA and CBZ-CR, however, both SFR for 52-week MP and TTFS during MP were in favor of LTG + VPA than CBZ-CR. The study suggested that LTG + VPA can be an option as initial drug regimen for untreated patients with partial seizures and/or GTCS except for women of reproductive age.

We investigated the indirect UV/ozone treatment, which means treating the insulator surface under tens of nanometers, rather than the direct surface of the insulator. The double-stacked organic layers are used as gate insulator and the UV/ozone treatment is conducted between these two layers. We analyzed the surface morphologies of the gate insulator and the pentacene by atomic force microscopy (AFM) to confirm the effect of indirect UV/ozone treatment. The UV/ozone treatment reduced the surface roughness of the upper side gate insulator and increased the pentacene grain size. Pentacene-based thin film transistors were fabricated and the electrical property improvement after this treatment was examined. The largest improvement was found when the UV/ozone treatment time is 10 min and the upper side gate insulator thickness is 20 nm, and the mobility at that condition is 1.21 cm2/V s, which is larger than three times that without UV/ozone treatment (0.33 cm2/V s).

It is important to establish a systematic education and training system for specialists in order to provide stable supply and demand of specialists who work in the railway field. Recently, In the revision of the Railway Safety Law, It is necessary to strengthen the capacity of railway specialists in response to changes in the railway environment. Therefore, in this paper, we analyze the training situation of domestic and foreign railway specialists and draw up the improvement methods of railway education training system. Based on these, we proposed the education training system construction for workers of railway operators.

This paper presents particular methods for deployment of precision control of a sensorless permanent magnet brushless DC (PM BLDC) motor using PLL control algorithm. Firstly, we utilizes the third harmonic of the motor internal voltages to determine the commutation instants of the PM BLDC motor for sensorless control. The waveform of the motor internal voltages (or back emf) contains fundamental and higher-order frequency harmonics. Therefore, the third harmonic component is extracted from the stator phase voltage. The resulting third harmonic signal maintains a constant phase relationship with the rotor flux at any motor speed and load condition. And is practically free of noise that can be introduced by the inverter switching, making this a robust sensing method. As a result, the method described here is not sensitive to filtering delays, allowing the motor to achieve a good performance over a wide speed range. For conventional 6-pulse control using the Hall-IC alone, this sensor misalignment would pose problems such as excessive torque ripple, noise, and inefficiency. Therefore, to implement the third harmonic sensing methods and speed control algorithm in this paper, the principle of the Johnson counter is used and it can estimate the same Hall-ICs signal with a non-difference phase resulting from the signals of the Johnson counter. Also, to precise control of a sensorless PM BLDC motor, we applied the position signal of phase lock loop (PLL) control algorithm and the remainder scheme in this paper, thus one can operate PM BLDC motor in high performance. Also, a simple starting method and speed estimation approach are proposed. Simulation an experimental results are provided, to demonstrate the validity of the precision control of a sensorless PM BLDC motor using PLL control algorithm.

In this paper, a contact loss simulator for a rigid catenary system was designed and used to analyze the effect on the power source according to the conditions of the rigid catenary system and pantograph. R-bar applied to a high-speed train among the real rigid catenary system was used in the contact loss simulator for rigid catenary systems. The excitation frequency generated with the movement of the railway vehicle was simulated. The characteristics according to the frequency and amplitude of the excitation frequency and the presence or absence of pantograph movement were analyzed. This work is considered to be helpful in analyzing the characteristics of contact loss in the interface between a real rigid catenary system and a rail vehicle.