bluuebunny/crossref_metadata_2025 huggingface dataset:
The smart power cell concept: mastering TSO–DSO interactions for the secure and efficient operation of future power systems
Authors: Mayorga Gonzalez Daniel , Myrzik Johanna , Rehtanz Christian
Published: March 2020

This article describes a novel power system architecture and operational concept which is founded on the idea of organising sets of distributed generators, loads, storages and multimodal interfaces at distribution level in supervised and controlled grid subsections called smart power cells, which are controllable entities intended to enforce the stability of the transmission network and participate in its operation. Further, the article addresses a control scheme which can be implemented within a smart power cell to control its active and reactive power exchange with the transmission network following set points provided by a superimposed control system, and thus participate in the operation of the transmission grid (e.g. participation in congestion management, system optimisation, balancing of generation and load). The dynamic behaviour of a future power system under consideration of the proposed system architecture including several smart power cells controlled with the developed control scheme is demonstrated through time‐domain simulation using a combined transmission–distribution power system model.
Stabilisation of central wavelength of erbium‐doped fibre source as part of high‐accuracy FOG
Authors: Vostrikov Evgenii , Kikilich Nikita , Zalesskaya Yulia , Aleinik Artem , Smolovik Mikhail , Deyneka Ivan , Meshkovskii Igor
Published: March 2020

The stability of the central wavelength of the erbium‐doped fibre source (EDFS) is one of the most important parameters to ensure the accurate operation of navigation systems based on high‐accuracy fibre optic gyroscopes (FOGs). In this study, the method of stabilisation of the EDFS as a part of the FOG is presented. The main advantage of this method is the possibility of quick and simple matching of temperature‐compensating spectral filters by changing the pump ratio without modifying the optic scheme. The EDFS optic scheme based on the double‐pass bidirectional pumping configuration. It makes it possible to obtain the world‐class stability of the central wavelength of the EDFS as a component of different devices with the spectral selectivity and set the constant value of the optic power of the output light (OL). Also, this is the first study of the dependence of the temperature coefficient of the central wavelength on the pump ratio. The proposed method allows compensating the spectral characteristics of the FOG, achieving the OL central wavelength stability around 0.7 ppm/°C and the FOG scale factor stability around 0.73 ppm/°C.
Analysis and design of a high voltage‐gain quasi‐Z‐source DC–DC converter
Authors: Abbasi Aghdam Meinagh Farhad , Yuan Jing , Yang Yongheng
Published: March 2020

In this study, a modified DC–DC converter is proposed, which can achieve a high voltage‐gain exploiting both quasi‐Z‐source and switched‐capacitor networks. In addition to the high voltage‐gain, the proposed converter has low voltage stresses on its elements. The steady‐state analysis in both continuous and discontinuous conduction modes is given in this study. Moreover, the design of the passive elements, the calculation of the non‐ideal voltage gain, and the power loss analysis are done. Then, an extended topology of the proposed converter is presented, which further enhances the voltage gain, while maintaining the voltage stresses of the components. A comprehensive comparison with the prior‐art converters is performed to accentuate the advantages of the proposed converter. Finally, simulations and experimental tests are provided to substantiate the theoretical analysis.
Technique for stability enhancement of microgrids during unsymmetrical disturbances using battery connected by single‐phase converters
Authors: Milošević Dejan , Đurišić Željko
Published: March 2020

This study proposes a technique for the enhancement of the stability of microgrids during unsymmetrical temporary faults in the distribution network. In order to enhance the transient stability and the quality of voltage in the microgrid during different disturbances caused by faults in the distribution network, this study proposes a concept with a centralised battery energy storage system. The battery is connected to the network through single‐phase converter units which are to be implemented in every phase so that they can inject independently both the active and reactive power in certain phases. The proposed technique enhances the transient stability of microgrids and provides symmetrical operating conditions for consumers and generators in it during all temporary symmetrical and unsymmetrical faults in the distribution network. An innovative concept has been proposed for managing the balance of active and reactive power that uses, as control variables, magnitude and voltage phase angle at the point of connection of the microgrid to the distribution system. The proposed concept and technique have been tested on the IEEE 33 BUS system with additional sources. The dynamic simulations of disturbances and the verification of the proposed technique have been performed in DIgSILENT PowerFactory software.
Composite generation and transmission expansion planning toward high renewable energy penetration in Iran power grid
Authors: Asadi Majd Aida , Farjah Ebrahim , Rastegar Mohammad
Published: March 2020

This study proposes a composite generation and transmission expansion planning (CGTEP) with high renewable penetration in Iran power grid. The goal is to minimise the generation and transmission investment and operation costs, start‐up/shut‐down costs, and the cost of energy not served during a 10‐year planning horizon. The problem is formulated in a mixed‐integer linear format, considering power flow limits, ramping rate limits, minimum up/down times of the generation units, uncertainty of wind and solar generations, and deterministic and probabilistic reliability constrains including reserve margins for generation capacities and expected energy not supplied boundary. In addition, according to the specific geographic characteristics of Iran, import and export of the electricity, as well as the limitation of water resources for power generation, is modelled in the CGTEP problem. The proposed CGTEP method is implemented in business as usual and renewable target cases without considering the uncertainty, and RT case with uncertainty considerations. In RT cases, 30% renewable penetration is targeted to reduce the CO2 emission by 10%. In addition, the capability of Iran power grid in providing green energy for the neighbouring countries is investigated in this study.
Simulation and experimental illustration of vibration at load rejection in a continuously overloaded large hydrogenerator
Authors: Carounagarane Carunaiselvane , Chelliah Thanga Raj , Appa Sarma SuriVenkata
Published: March 2020

Large hydro generators are usually overloaded at various situations such as the period when excess water is available and when excess inflow is to be discharged. The period may have extended to many weeks under exigent conditions e.g. six weeks in case of a 1000 MW hydropower plant (HPP) located at northern region, India at 20% overload. All the performance related parameters including vibrations were observed during commissioning except runaway speed test at load rejection. At overloads, if there is a sudden load rejection the vibration transients will be even more severe due to drop in current and internal impedance. Hence this paper aims to analyze the vibration signature of large synchronous generator (SG) when operated at overloads and subjected to sudden load rejection. The substantiation of the factual model of 250 MW hydro generating units (HGU) replicating the case plant has been simulated using SIMSEN software. Apart from case report and simulative validation an experimental verification is also conducted with a prototype model of 2.2 kW SG. This paper provides the feasibility to operate the SG's 20% beyond its rated load as designed with proper maintenance and safety carried out by plant operators.
Optimal wave energy extraction for oscillating water columns using second‐order sliding mode control
Authors: Mosquera F. D. , Evangelista C. A. , Puleston P. F. , Ringwood J. V.
Published: March 2020

Ocean waves are an important renewable energy resource and several fields of are concurrently working to improve technologies for harnessing their power. In that context, this study presents a control to optimise the performance of oscillating water column systems. As a first contribution, a novel criterion to attain maximum wave energy extraction is developed, resulting in an enhancement of the global power efficiency of the system. Then, taking advantage of the proposed criterion, a second‐order sliding mode control set‐up is designed, with power extraction maximisation the primary objective and reactive power regulation a secondary one. Simulation results confirm the highly satisfactory performance of the proposed controller and its robustness in the presence of the inherent uncertainties and disturbances in the non‐linear system.
Hierarchical energy management scheme for residential communities under grid outage event
Authors: Zhang Fangfei , Luo Fengji , Dong Zhaoyang , Liu Yanli , Ranzi Gianluca
Published: March 2020

The ever‐increasing energy demand and extreme weather days lead to more frequent power outage events. This paper proposes a hierarchical energy management scheme for residential communities, aiming to facilitate energy sharing among houses and minimize the impact on the grid outage on the whole community. In the proposed model, the complexity of scheduling residential energy resources of multiple houses is decomposed into a bi‐level structure, in which the Home Energy Management System (HEMS) of each house iteratively interacts with the Community Energy Management System (CEMS). In the upper layer, the CEMS receives the information of the planned outage; it then solves a social warfare optimization model to determine: (1) charging/discharging power of a community battery energy storage system, and (2) load re‐shaping instructions of each house. In the lower layer, the HEMS of each house performs appliance‐level autonomous scheduling to try to satisfy the load re‐shaping instructions received from the CEMS. The autonomous scheduling result of individual HEMSs are sent back to the CEMS, and the latter updates the upper‐layer result based on the received result. This process continues until the convergence criteria is achieved. Extensive simulations are conducted to validate the proposed solution
Rise and fall of the high-energy afterglow emission of GRB 180720B
Authors: Ronchi M. , Fumagalli F. , Ravasio M. E. , Oganesyan G. , Toffano M. , Salafia O. S. , Nava L. , Ascenzi S. , Ghirlanda G. , Ghisellini G.
Published: March 2020

The gamma-ray burst (GRB) 180720B is one of the brightest events detected by the Fermi satellite and the first GRB detected by the H.E.S.S. telescope above 100 GeV, at around ten hours after the trigger time. We analysed the Fermi (GBM and LAT) and Swift (XRT and BAT) data and describe the evolution of the burst spectral energy distribution in the 0.5 keV–10 GeV energy range over the first 500 s of emission. We reveal a smooth transition from the prompt phase, dominated by synchrotron emission in a moderately fast cooling regime, to the afterglow phase whose emission has been observed from the radio to the gigaelectronvolts energy range. The LAT (0.1–100 GeV) light curve initially rises (FLAT ∝ t2.4), peaks at ∼78 s, and falls steeply (FLAT ∝ t−2.2) afterwards. The peak, which we interpret as the onset of the fireball deceleration, allows us to estimate the bulk Lorentz factor Γ0 ∼ 150 (300) under the assumption of a circum-burst medium with a wind-like (homogeneous) density profile. We derive a flux upper limit in the LAT energy range at the time of H.E.S.S. detection, but this does not allow us to unveil the nature of the high-energy component observed by H.E.S.S. We fit the prompt spectrum with a physical model of synchrotron emission from a non-thermal population of electrons. The 0–35 s spectrum after its EF(E) peak (at 1–2 MeV) is a steep power law extending to hundreds of megaelectronvolts. We derive a steep slope of the injected electron energy distribution N(γ) ∝ γ−5. Our fit parameters point towards a very low magnetic field (B′ ∼ 1 G) in the emission region.
Disaster-based participatory development planning
Authors: Hidayat Benny , Rasadi Anggraini
Published: March 2020

Disasters are a global problem in many countries. Particularly in Indonesia,where has many prone areas to disasters. The perspective of disastermanagement has entered a new paradigm, from previously only focusing onemergency response activities to mitigation and preparedness approaches. Mitigation andpreparedness are carried out when disasters do not occur. Indisaster risk mitigation, it is necessary to involve active communityparticipation, especially in planning for disaster-related development. So far, the communities are mostly only passive object in the development program that only accepts any initiatives of disaster-based development made by thegovernment. The communities need to be placed as active subjectsparticipating in the disaster-related development in their community. Many disaster-based infrastructure developments so far still use the top-downmechanism, namely disaster planning, and management entirely based on the initiation of the government or organization. In Disaster Management Law No.24/2007, it is stated that the community has the right to be actively involved indisaster management efforts in their communities. This paper aims to identifywhat forms of community participation in disaster-based development,especially at the planning stage of infrastructure development activities.
Lombok earthquake, one year later: housing sector recovery
Authors: S Pribadi Krishna , G Pradoto Rani , A Hanafi Eliya , Adhi Bayu Rasmawan I Made
Published: March 2020

The series of strong earthquakes that hit the province of West Nusa Tenggara (NTB) on 29 July 2018 (M6.4), 5 August 2018 (M7.0), 9 August 2018 (M6.2) and 19 August 2018 (M6.5 and M6.9) has caused many casualties, injuries as well as damages in the housing sector. The disaster emergency was stated on July 29th, 2018 and was extended several times up to August 25th, 2018. A transition period from an emergency situation to recovery was declared starting from August 26th, 2018 to February 26th, 2019, while the rehabilitation and reconstruction (R & R) phase was started from February 27th. , 2019. In the R & R program, the Government has established a policy of building earthquake-resistant houses with a self-managed system through the formation of community groups (POKMAS) consisting of house owners, supported by technical and administrative facilitators. There are many models of earthquake resistant houses, both those proposed by the government and the private sector that are approved by the government. A Presidential Instruction (Inpres) Number 5 Year 2018 was issued on 23 August 2018 to provide guidance on the housing sector reconstruction. An investigation to study and document the lessons learnt from the housing reconstruction process is conducted in Lombok Island, covering the issues of program management, institutional set up and coordination, project administration, technical design, quality assurance and community participation. It was found that there were so many house building models proposed to the community by various sponsors, which cause confusion to the affected community. The study also found that the house reconstruction program has been delayed during the process, as one year after the earthquake, there were only about 52 thousands houses which have been completed, and 80 thousands other are still in progress, compared to the total of more than 237 thousand affected houses to be repaired and rebuilt. The study is expected to reveal various impeding issues and propose solutions for expediting the process. It is also expected that the result of the study can be used as a reference for future post-disaster housing sector recovery program in other places.
Effect of soil structure disturbance on the shear strength of black volcanic ash soil
Authors: Asfino Putra Okri , Yasufuku Noriyuki , Ishikura Ryohei , Rifa’i Ahmad , Alowaisy Adel , Kawaguchi Yuko
Published: March 2020

The effect of soil disturbance on the shear strength of black volcanic ash soil was investigated using a constant volume direct shear apparatus. Disturbance of soil structure was considered as the pore size distribution which obtained from the soil-water characteristic curve (SWCC). The disturbed sample was used as a representation of soil structure disturbance due to earthquake shakes. A series of cyclic tests were conducted under unsaturated and saturated samples. It was found that the undisturbed samples exhibit a unimodal pore structure, and the disturbed samples indicate to a bimodal pore structure. Since the pore structure of the disturbed sample is unstable, the degradation index value is higher than that of the undisturbed sample and increases with the increasing number of cycles. In other words, the cyclic normalized vertical stress of disturbed samples degrades faster. Furthermore, the degradation index value in the normallyconsolidated samples was found to be larger than the overconsolidated. It might be attributed to increasing of the pore water pressure during shearing. Where in the over-consolidated samples is lower than normally-consolidated. On the other hand, the normalized shear stress of unsaturated samples, it is slightly larger due to the suction forces in the total strength of soils.
Swedish Weight Sounding: A prospective portable soil investigation tools for liquefaction assessment of residential houses in Indonesia
Authors: Muhamad Yusa , Elisabeth T. Bowman , S.A Nugroho
Published: March 2020

National Disaster Management Agency (BNPB) statistics show that the majority of earthquake affected buildings are residential houses, whereas in practice, soil investigation is rarely conducted for residential houses in Indonesia. This study is preliminary work on the prospective of Swedish Weight Sounding (SWST) for liquefaction assessment for residential houses. Material used is poorly graded sand. The number of half turns from SWST (NSW) per meter for very loose and loose clean fine sand ranges from 4 to 168 (equivalent to SPT 0-30). Liquefaction potential was assessed using an indirect method by converting NSW into equivalent NSPT and direct method. In general, the factor of safety obtained from the direct method is more conservative (thus giving lower liquefaction potential index) than the indirect method. Torque measured for material in this study ranged from 6-54 Nm, equivalent to a specific energy range from 7-70 N/mm2. Liquefaction assessment using SWST data with torque measurement also indicated the soil is liquefiable. SWST also may be able to detect sand ageing. In summary SWS has a good prospect as a highly portable and low cost investigation tool for liquefaction assessment of residential houses in Indonesia.
Numerical model for investigating seismic performance of Prestressed Hollow Concrete (PHC) piles with Fiber section element
Authors: Setiawan Angga Fajar , Darmawan Muhamad Fauzi , Ismanti Sito , Mukhlis Sunarso , Guntara Muria Adityawarman
Published: March 2020

In the medium to high seismic zone, prestressed hollow concrete (PHC) pile for structural foundation should be designed with elastic behavior due to low ductility and dissipated energy. However, some Indonesian practical engineer has chosen PHC pile for pile-supported slab viaduct (PSSV) with medium seismic moment-resisting frame concept in a high-risk earthquake zone. Therefore, some nonlinear numerical simulations of PSSV structure in medium to high seismic zone need to be conducted to investigate its seismic performance. In the initial stage, a numerical model for investigating the seismic performance of PHC pile under flexural test was conducted. By implementing an appropriate plastic hinge length of forced beam-column with hinge elements, the flexural behavior of PHC piles to be simulated under both monotonic and cyclic loading. The fiber section was adopted to accommodate non-linear behaviour of material in the PHC pile cross section. As the results, the skeleton curves, the sectional strain distributions, and the hysteresis curves have good agreement results compared with the experimental results. Furthermore, based on the equal damping ratio calculation of the hysteresis curve, the PHC pile only achieve low energy dissipation, though the ductility capacity around 3. Finally, this numerical model approach could be adopted in the non-linear simulation of PSSV structure under seismic load.
Risk analysis of seismic bridge damage: case study after Lombok and Palu earthquake
Authors: Putra Risma , Adi Riyono Winarputro
Published: March 2020

Indonesia is known as an earthquake-prone region, lies in the ring of fire zone. This potential hazard can impact several infrastructures, including bridges. Seismic bridge damages could possibly disrupt traffic flow furthermore cut off the regional connectivity. In this study, risk analysis is carried out on several bridges after Lombok and Palu earthquake. Visual inspection has been undertaken on 38 bridges on-site, and several damages identification are reported. Risk analysis was then carried out according to the severity of element damages and the frequency of occurrence. From the analysis, it is concluded that embankment settlement in the approach road is found to be the most potential element with the highest risk of damage due to earthquakes. Besides, the superstructure displacement and crack in the wing wall are at moderate risk. This finding makes the substructure become the most vulnerable element which needs more attention. Therefore, it is recommended to specify a higher design specification for substructure to mitigate seismic bridge damages, especially for bridges located in the high seismic zone area.
Assessment of road traffic performance of the Tsunami evacuation road in Padang Municipality area based on the traffic volume simulation approach
Authors: Yossyafra Yossyafra , Fitri Nurhuda , Sidhi Rahmat Punama , Yosritzal Yosritzal , Mazni Deni Irda
Published: March 2020

There are many cities on the west coast of the Sumatra, which are at high risk of the Tsunami disaster. Regional Regulations on Regional Spatial Planning for each City/ Regency have compiled disaster mitigation by constructing several evacuation roads. This study wants to illustrate: what are the volume of traffic generation and road performance, if there is a Tsunami disaster. The simulation is developed by predicting traffic volume based on parameters, population density, vehicle ownership, land use, and activities in the area around the road. The assessment was carried out on two tsunami evacuation roads in the city of Padang, West Sumatra Province. The results show that the highest traffic volume occurred in the period from 06.30 a.m until 3:00 p.m., during school activities. One of the roads will not be able to accommodate the volume of traffic during a disaster, due to significant traffic congestion. This study shows that: (1) the period of activity and land use are two main parameters, which must be considered in designing tsunami evacuation roads, (2) The degree of saturation ratio and the ratio between the capacity of sections of Tsunami evacuation routes can be proposed as a parameter for assessing the performance of Tsunami evacuation roads in urban areas.
Seismic capacity evaluation of the damaged reinforced concrete building during Palu earthquake 2018
Authors: Nugroho Fajar
Published: March 2020

This paper presents an evaluation of the seismic capacity of the Dean Building of The Faculty of Social and Political Science of Tadulako University due to the Palu Earthquake 2018. The building was built in 2016 and went into use in 2017. The building is made from a reinforced concrete frame consisting of three floors and collapsed after the earthquake. Data for the analysis are taken from the Detail Engineering Design of the Dean Building of The Faculty of Social And Political Science of Tadulako University in 2015. Seismic capacity evaluated based on Standard for Seismic Evaluation of Existing Reinforced Concrete Buildings issued by the Japan Country. The analysis are done on the 1st-floor structure because the most significant sliding force happens on the first floor. Seismic capacity is invoked in the form of a link between the lateral strength and the ductility index. By using Japanese standards, the building's seismic capacity is relatively small in withstanding the earthquake load and collapsed the building. Based on observations in the field by conducting non-destructive testing using hammer tests, the concrete material had relatively low quality and a failure to connect the column beams by insufficiently reintegrating and resulted in a collapse of the building.
Schwierige Therapieentscheidungen bei Schlaganfall und Demenz – Aspekte bei schweren vaskulären und fortgeschrittenen degenerativen Hirnerkrankungen
Authors: Guldner Jürgen
Published: March 2020

Severe stroke and neurodegenerative diseases often cause limitations in communication and willing capability. Decision processes in these conditions assume primarily a positive medical indication for any intervention. If not obtainable from an individual by itself, by a disposal or by a legal custodian, the presumed will of a patient has to be detected carefully. Evidence can be raised by an interview of relatives or an individual case discussion in a local ethical comitee. Stroke and dementia can raise the need for palliative care, especially a sufficient analgesia as well as other severe illnesses. Pain in demented persons is often underrated and undertreated. The diagnosis of dementia alone does not limit the indication for curative therapy in general. Ethical comitees or ethical visits are helpful instruments to find out an adequate decision in difficult situations.
An Ethanolic Extract of Boehmeria caudata Aerial Parts Displays Anti-inflammatory and Anti-tumor Activities
Authors: de Paiva Paula Pereira , Nonato Fabiana Regina , Ruiz Ana Lúcia Tasca Gois , Sousa Ilza Maria de Oliveira , Zafred Rafael Rosolen Teixeira , de Oliveira Diogo Noin , Catharino Rodrigo Ramos , Foglio Mary Ann , de Carvalho João Ernesto
Published: March 2020

The tumor microenvironment presents several therapeutic targets, with inflammation being one of them. In search of new drugs, plants have shown to be an effective source of potent anti-inflammatory and anticancer agents. This study aimed to evaluate the antitumoral and inflammatory activities of Boehmeria caudata aerial parts extract. Bioguided in vitro antiproliferative screening showed that phenanthroquinolizidine obtained from the aerial B. caudata ethanolic extract had a straight relationship with activity. Moreover, the orally administered ethanolic extract reduced Ehrlich solid tumor growth and displayed an anti-inflammatory effect in both evaluated experimental models (carrageenan-induced paw edema and croton oil-induced ear edema). These results suggest that the antitumor activity of the ethanolic extract could be explained by antiproliferative effects associated with anti-inflammatory action.
Osteotomies—When, Why, and How?
Authors: Locketz Garrett D. , Lozada Kirkland N. , Becker Daniel G.
Published: March 2020

An ideal nasal osteotomy should deliver precise, predictable, and reproducible cosmetic and functional results while minimizing soft-tissue trauma and postoperative complications. In addition to closing an open roof deformity after hump reduction, other common indications for osteotomies include the crooked nose and a wide bony vault. The literature has reported numerous and diverse osteotomy techniques as well as differences in timing of osteotomies. Each has its own merits and indications, and its proponents. In this article, we review the anatomy and nomenclature relating to osteotomies. We review the locations and paths of the osteotomies—lateral, intermediate, medial, and superior/transverse. We consider the percutaneous and endonasal approaches, as well as timing of osteotomies and other considerations. We also discuss technical considerations in the selection of instrumentation for osteotomies.
Nasal Obstruction after Mohs Surgery: Prevention and Correction
Authors: Rudy Shannon F. , Moyer Jeffrey S.
Published: March 2020

As rates of Mohs micrographic surgery (MMS) have risen over recent decades in the setting of increased incidence of nonmelanoma skin cancer, so too has the need for post-Mohs reconstruction. The nose is one of the most common sites of post-MMS nasal reconstruction and presents unique challenges that often require expertise in facial plastic and reconstructive surgery. In addition to the aesthetic importance of the nose, preserving nasal function and preventing nasal obstruction are paramount to successful nasal reconstruction. This article will provide a brief review of nasal anatomy, with a focus on particular anatomic risk factors for post-MMS reconstruction nasal obstruction, strategies to prevent nasal obstruction, as well as techniques to correct the problem when it arises.
Diaphyseal Screw Prominence in Distal Radius Volar Plating
Authors: Eng Kevin , Gil Stephen , Page Richard
Published: March 2020

Background Volar plating for distal radius fractures has become common. Screw prominence on the dorsal side from long screws can lead to tendon injury. Methods for detecting screws that penetrate the far cortex involve X-ray or ultrasound. These have focused on the distal row of screws. No studies have addressed screw penetration in the diaphysis. We describe two cases where diaphyseal screws caused symptoms. We then insert screws in the diaphysis of synbones 2 mm longer than measured and determine what angle of pronation or supination was best to detect this on X-ray.

Methods Three synbones were plated using Synthes volar plate. The three diaphyseal screws were drilled perpendicular to the plate, and the depth measured. Cortical 2.4-mm screws were inserted, 2 mm longer than measured. The three synbones were then placed in a custom clamp to measure rotation. Lateral X-rays were taken at 0 degree rotation, and 5, 10, and 15 degrees of supination and pronation. The prominence of each screw was measured using the synapse digital ruler.

Results For the screws that were placed at a neutral angle (perpendicular to the plate) the maximum visualization of the prominent tips occurred around 0 degree rotation. With screws angled 15 degrees ulna, maximum visualization was between 5 and 10 degrees of pronation. With screws angled 15 degrees radial, maximum visualization was between 5 and 10 degrees of supination. Every 5 degrees of rotation changes the profile of the screw by 0.4 mm.

Discussion The diaphysis of the radius becomes approximately trapezoidal distally. Prominent screws that are placed below the “peak” of the trapezoid may appear to be the correct length. Rotating the wrist into pronation or supination to bring the relevant cortex as parallel to the X-ray beam as possible will help to identify if screws are of the correct length. Screws that are prominent in the second compartment may be particularly symptomatic as the tendons here are closely opposed to the bone. We recommend screening for 2 mm diaphyseal screw prominence in neutral, with 10 degrees of pronation and supination.
Evaluation of Flexor Pollicis Longus Tendon Rupture after Treatment of Distal Radius Fracture with the Volar Plate
Authors: Yamak Kamil , Karahan Hüseyin Gökhan , Karatan Berrak , Kayalı Cemil , Altay Taşkın
Published: March 2020

Background The aim of this study is to evaluate the frequency of flexor pollicis longus (FPL) tendon rupture and factors leading to this rupture during the follow-up of patients who underwent volar plate fixation because of distal radius fracture.

Patients and Methods A total of 109 distal radius fractures of 102 patients treated with volar plate fixation and periodically followed up for at least 1 year between January 2013 and May 2018 were evaluated. Fractures were categorized according to the AO Foundation/Orthopaedic Trauma Association (AO/OTA) Fracture-Dislocation Classification and Soong's grading was used for classifying volar plate position. All patients operated were inquired retrospectively in terms of flexor tendon rupture.

Results Gender distribution revealed 45 females and 57 males. Mean age was 47.9 (range: 17–88) years. Mean period of follow-up was 27 months. Distribution of fractures in accordance with the AO/OTA distal radius classification was 6, 8, 7, 12, 24, 33, 11, and 8 patients with types A2, A3, B1, B2, B3, C1, C2, and C3, respectively. When volar plate positions were analyzed with Soong's classification, it revealed that 79 (72.4%), 23 (21.1%), and 7 (6.5%) plates were grade 0, 1, and 2, respectively. In total, evaluating the three patients with FPL rupture, it revealed that the volar plate was positioned distally during fixation because the fracture line had advanced to the distal of the watershed line, the distal portion of the plate had lost complete connection with the bone, and at this portion, it was observed that the pronator quadratus muscle was not covering the plate entirely (Soong's classification grade 2). Patients did not have additional flexor tendon injury.

Conclusion FPL tendon rupture is a rare but serious complication of volar plate fixation performed for distal radius fractures. We believe that appropriate choice of implant and careful surgical technique, along with the close follow-up of patients, with Soong's classification grade-2 volar positions would help in preventing this complication.

Level of Evidence This is a Level 3a, differential diagnosis/symptom prevalence study.
Clinical Tips of Cesarean Section in Case of Breech, Transverse Presentation, and Incarcerated Uterus
Authors: Takeda Jun , Ishikawa Gen , Takeda Satoru
Published: March 2020

Cesarean section in breech or transverse presentation involves more complicated procedures than cesarean section in cephalic presentation because the former requires additional manipulations for guiding the presenting part of the fetus, liberation of the arms, and the after-coming head delivery; therefore, those cesarean sections are likely to be more invasive. Making a rather wide uterine incision to prevent uterine injury during delivery of the fetus facilitates smooth delivery of the fetus. Furthermore, in cases of breech or transverse presentation, it is important to initially identify the presenting part of the fetus and guide it to the incision opening in the lower uterine segment, because delivering the presenting part of the fetus first is a basic rule of delivery of the fetus. Smooth delivery of the fetus by means of breech extraction can prevent excessive stress or injury to the fetus. Therefore, it is important to acquire the knowledge and skills necessary to perform these techniques, including the internal version. Smooth delivery of the fetus is also less invasive for the mother because an extension of the uterine excision or injury to arteries and veins in the uterus and parametrium can be avoided. Incarcerated uterus occurring in cases of pregnancy with intrapelvic adhesion, endometriosis, cervical myoma, or extended cervix may result in excessive uterine and cervical injury when a transverse incision of the lower uterine segment is performed without caution. These conditions may result in difficulty in fetal delivery. Therefore, it is important to identify risks in advance and to choose the incision line with great care. Countermeasures for difficult delivery of the fetus need to be mastered by all practitioners of obstetrics. If the transverse incision fails to reach the uterine cavity, an inverted T-shaped or J-shaped incision should be made. Risks of complications such as injury to the cervical canal, the vagina, the bladder or ureter, and massive hemorrhage must be kept in mind.
Direct measurement of 1-mN-class thrust and 100-s-class specific impulse for a CubeSat propulsion system
Authors: Asakawa J. , Nishii K. , Nakagawa Y. , Koizumi H. , Komurasaki K.
Published: March 2020

This paper presents the development of a thrust stand to enable direct measurement of thrust and specific impulse for a CubeSat propulsion system during firing. The thrust stand is an inverted pendulum and incorporates a mass balance for direct in situ mass measurement. The proposed calibration procedure allows precise performance characterization and achieves a resolution of 80 μN thrust and 0.01 g mass loss, by taking into account the drift of the thrust-stand zero caused by propellant consumption. The performance of a water micro-resistojet propulsion system for CubeSats was directly characterized as a proof of concept of the thrust stand. Continuous profiles of thrust, specific impulse, and mass consumption were acquired under various conditions in a single firing test. A thrust from 1 mN to 10 mN and a specific impulse from 45 s to 100 s with a maximum measurement uncertainty of ±15.3% were measured for the throat Reynolds number in the range 100–400.
New insights on fast ion-acoustic soliton stopbands and extension to dusty plasmas
Authors: Maharaj S. K. , Bharuthram R.
Published: March 2020

Large amplitude fast ion-acoustic solitons are revisited in a three-component plasma composed of cold ions, warm (adiabatic) ions, and hot Boltzmann electrons to determine where the limits occur in the ranges of the warm ion-to-electron temperature ratio τ and the charge-to-mass ratio of the cold ions relative to the warm ions μ for the existence of stopbands. The warm (adiabatic) ion limiting curve evolves in a similar fashion for increasing values of τ or decreasing values of μ in supporting the existence of stopbands when the warm ion limiting curve is double-valued in the Mach number over part of a range of cold ion densities, to the disappearance of the stopbands when the warm ion limiting curve is single-valued over the complete range of cold ion densities. The bifurcation of the warm ion limiting curve into an upper and lower branch indicates the transition region in parameter space, which is between the region where stopbands are supported and the region where stopbands do not occur. The stopbands are found to have an infinite extent over the range of cold ion densities in the transition region. The widening (or narrowing) of the stopbands over the range of cold ion densities associated with a kappa (or Cairns) distribution of hot ions in a four-component plasma is found to be much weaker than non-thermal electron effects on the stopbands as reported by Maharaj and Bharuthram [Phys. Plasmas 24, 022305 (2017)].
Plasma and trap-based techniques for science with antimatter
Authors: Fajans J. , Surko C. M.
Published: March 2020

Positrons (i.e., antielectrons) find use in a wide variety of applications, and antiprotons are required for the formation and study of antihydrogen. Available sources of these antiparticles are relatively weak. To optimize their use, most applications require that the antiparticles be accumulated into carefully prepared plasmas. We present an overview of the techniques that have been developed to efficiently accumulate low energy antiparticles and create, in particular, tailored antiparticle plasmas. Techniques are also described to create tailored antiparticle beams. Many of these techniques are based on methods first developed by the nonneutral plasma community using electron plasmas for increased data rate. They have enabled the creation and trapping of antihydrogen, have been critical to studies of positron and positronium interactions with matter, including advanced techniques to characterize materials and material surfaces, and have led to the creation and study of the positronium molecule. Rather than attempting to be comprehensive, we focus on techniques that have proven most useful, applications where there has been significant, recent progress, and areas that hold promise for future advances. Examples of the latter include the ever more precise comparisons of the properties of antihydrogen and hydrogen, tests of gravity using antihydrogen and positronium atoms, and efforts to create and study phases of the many-electron, many-positron system.
Design of TE01-to-HE11 mode converters for high-power millimeter wave applications at 35 GHz
Authors: Gu Ling , Liu Yinghui , Chen Shuang
Published: March 2020

Based on the coupled wave theory, we have designed the TE01–HE11 high efficiency and high-power mode converter at 35 GHz through the method of numerical simulation, where the TM11 mode is used as the intermediate mode. The ohmic losses due to the metal walls are taken into account in the calculations, and rematching phase techniques are used to increase the conversion efficiency. Modeling analysis is performed using commercial CST Microwave Studio software, and the cold test is performed. Experimental results verify the accuracy of numerical simulation.
N doped ZnO (N:ZnO) film prepared by reactive HiPIMS deposition technique
Authors: Wang Zhengduo , Li Qian , Yuan Yan , Yang Lizhen , Zhang Haibao , Liu Zhongwei , Ouyang Jiting , Chen Qiang
Published: March 2020

In this paper, we report a nitrogen (N) doped zinc oxide (N:ZnO) film grown by the reactive high power impulse magnetron sputtering (HiPIMS) technique on glass substrates, where nitrogen gas (N2) is used as the N source. The proposal is to investigate the influence of process parameters on the alteration of the N:ZnO film from n- to p-type conductivity and the stability of the p-type behavior. It is obtained that the n- or p-type behavior of the as-deposited N:ZnO film is affected by the N2 flow rate, deposition temperature, and inductively coupled plasma (ICP) assistance, of which the ICP assistance had a great impact. It is noticed that, owing to the improved ionization rate of the N2 dopant by ICP, the N:ZnO film almost totally prefers to exhibit p-type behavior. Based on the measurement by temporal resolution optical emission spectroscopy, the components in plasma are obtained and the ion reaction in film growth is confirmed: a high concentration of active N+ in the ICP-assisted plasma reacts with sputtered Zn+ in vapor to form No defect in the p-type N:ZnO film. We then forecast that a stable p-type N:ZnO film can be grown using the HiPIMS technique.
Positive effects in perovskite solar cells achieved using down-conversion NaEuF4 nanoparticles
Authors: Ran Meiqing , Liu Nan , Yang Hao , Meng Rangwei , Chen Mengwei , Lu Haifei , Yang Yingping
Published: March 2020

In this work, NaEuF4 nanoparticles (NPs) with high dispersity and uniformity were synthesized using a hydrothermal method and introduced into the TiO2 mesoporous layer of perovskite solar cells (PSCs) for testing as high efficiency, downconversion materials. NaEuF4 can convert high-energy photons into low-energy photons for absorption by CH3NH3PbI3 and generation of more electron–hole pairs; we tested the hypothesis that this would extend the sunlight absorption range and improve the photovoltaic performance of PSCs. When NaEuF4 NPs were incorporated into TiO2 mesoporous layers, PSCs achieved power conversion efficiencies of 14.51%, which were better than those of the control PSCs. The use of NaEuF4 NPs for improving PSC photovoltaic performance, as shown herein, could encourage the greater use of solar energy.
Bumps and oscillons in networks of spiking neurons
Authors: Schmidt Helmut , Avitabile Daniele
Published: March 2020

We study localized patterns in an exact mean-field description of a spatially extended network of quadratic integrate-and-fire neurons. We investigate conditions for the existence and stability of localized solutions, so-called bumps, and give an analytic estimate for the parameter range, where these solutions exist in parameter space, when one or more microscopic network parameters are varied. We develop Galerkin methods for the model equations, which enable numerical bifurcation analysis of stationary and time-periodic spatially extended solutions. We study the emergence of patterns composed of multiple bumps, which are arranged in a snake-and-ladder bifurcation structure if a homogeneous or heterogeneous synaptic kernel is suitably chosen. Furthermore, we examine time-periodic, spatially localized solutions (oscillons) in the presence of external forcing, and in autonomous, recurrently coupled excitatory and inhibitory networks. In both cases, we observe period-doubling cascades leading to chaotic oscillations.
Computational de-noising based on deep learning for phase data in digital holographic interferometry
Authors: Montresor Silvio , Tahon Marie , Laurent Antoine , Picart Pascal
Published: March 2020

This paper presents a deep-learning-based algorithm dedicated to the processing of speckle noise in phase measurements in digital holographic interferometry. The deep learning architecture is trained with phase fringe patterns including faithful speckle noise, having non-Gaussian statistics and non-stationary property, and exhibiting spatial correlation length. The performances of the speckle de-noiser are estimated with metrics, and the proposed approach exhibits state-of-the-art results. In order to train the network to de-noise phase fringe patterns, a database is constituted with a set of noise-free and speckled phase data. The algorithm is applied to de-noising experimental data from wide-field digital holographic vibrometry. Comparison with the state-of-the-art algorithm confirms the achieved performance.
Theoretical prediction on the R-branch lines for the first overtone transitions in the ground electronic state of 12C16O
Authors: Fan Zhixiang , Luo Chunrun , Fan Qunchao , Ma Haide , Fu Jia , Ma Jie , Xu Yonggen , Li Huidong , Zhang Yi
Published: March 2020

An analytical formula for the diatomic R-branch emission lines that was recently tested as a universal expression has been further modified based on the difference algebraic converging method. The tiny experimental line errors that may lead to amplified errors in the determination of high J lines were taken into account in the formula. Applications are presented for the R-branch emission spectra of (2-0), (3-1), (6-4), and (7-5) overtone bands of the ground electronic state of 12C16O. The rotational constants and band origins that are consistent with those reported previously are determined through the analytical formula for predicting frequency for emission lines up to J = 110. The results are shown to not only compare favorably with available lower J lines, but also generate reasonable higher J lines for the overtone bands, which agree with data from the HITRAN database and other works.