100 research outputs found
A Fast Solution Method for Large-scale Unit Commitment Based on Lagrangian Relaxation and Dynamic Programming
The unit commitment problem (UC) is crucial for the operation and market
mechanism of power systems. With the development of modern electricity, the
scale of power systems is expanding, and solving the UC problem is also
becoming more and more difficult. To this end, this paper proposes a new fast
solution method based on Lagrangian relaxation and dynamic program-ming.
Firstly, the UC solution is estimated to be an initial trial UC solution by a
fast method based on Lagrangian relaxation. This initial trial UC solution
fully considers the system-wide con-straints. Secondly, a dynamic programming
module is introduced to adjust the trial UC solution to make it satisfy the
unit-wise constraints. Thirdly, a method for constructing a feasible UC
solution is proposed based on the adjusted trial UC solution. Specifically, a
feasibility-testing model and an updating strategy for the trial UC solution
are established in this part. Numerical tests are implemented on IEEE 24-bus,
IEEE 118-bus, Polish 2383-bus, and French 6468-bus systems, which verify the
effec-tiveness and efficiency of the proposed method.Comment: 10 pages, journal paper, transaction
Multi-Slice Computer Tomography Dynamic Enhanced Expression and Clinical Significance of Hepatic Perfusion Abnormalities
Objective: To investigate the imaging features and clinical significance of the dynamic enhanced CT perfusion of the liver. Method: 112 cases of hepatic perfusion disorders were collected, including 22 cases of hepatocellular carcinoma with tumor thrombus, 12 cases of bile duct carcinoma, 16 cases of cholangitis, 31 cases of hemangioma, 10 cases of liver cirrhosis and liver laceration injury in 5 cases, 16 cases of liver abscess, all cases were surgically or clinically confirmed. All cases were performed with three phase enhanced scanning, and the images were loaded into the PACS system. Results: In 26 cases, 76 cases with patchy enhancement around the focus were shown in 10 cases with patchy enhancement. Arterial phase was in 47 cases, 12 cases with high perfusion, and 53 cases with high perfusion. Conclusion: Correct understanding of liver perfusion abnormalities in the diagnosis of lesions and reduce the true extent of the lesion is important
Shared Information-Based Safe And Efficient Behavior Planning For Connected Autonomous Vehicles
The recent advancements in wireless technology enable connected autonomous
vehicles (CAVs) to gather data via vehicle-to-vehicle (V2V) communication, such
as processed LIDAR and camera data from other vehicles. In this work, we design
an integrated information sharing and safe multi-agent reinforcement learning
(MARL) framework for CAVs, to take advantage of the extra information when
making decisions to improve traffic efficiency and safety. We first use weight
pruned convolutional neural networks (CNN) to process the raw image and point
cloud LIDAR data locally at each autonomous vehicle, and share CNN-output data
with neighboring CAVs. We then design a safe actor-critic algorithm that
utilizes both a vehicle's local observation and the information received via
V2V communication to explore an efficient behavior planning policy with safety
guarantees. Using the CARLA simulator for experiments, we show that our
approach improves the CAV system's efficiency in terms of average velocity and
comfort under different CAV ratios and different traffic densities. We also
show that our approach avoids the execution of unsafe actions and always
maintains a safe distance from other vehicles. We construct an
obstacle-at-corner scenario to show that the shared vision can help CAVs to
observe obstacles earlier and take action to avoid traffic jams.Comment: This paper gets the Best Paper Award in the DCAA workshop of AAAI
202
Multiple genetic analyses to investigate the polymorphisms of Chinese Mongolian population with an efficient short tandem repeat panel
Aim To determine allele frequencies and forensic statistics
of 22 autosomal short tandem repeat loci in Chinese Mongolian
population.
Methods Blood specimens were collected from 134 unrelated
healthy Mongolian individuals, and 22 short tandem
repeat loci were co-amplified and genotyped. Allele
frequencies and forensic parameters were calculated,
and population genetic differences were analyzed among
Mongolian population and other eight Chinese populations:
Northern Han, Guangdong Han, Chengdu Han, Xinjiang
Hui, Xinjiang Uygur, Hainan Li, Qinghai Tibetan, and
Hainan Han. Results All the loci were in the Hardy-Weinberg equilibrium,
and after Bonferroni correction there was no linkage
disequilibrium between them. The allele frequencies of
these 22 loci were between 0.0037 and 0.3657. This panel
had high discriminating power and genetic polymorphism
in the Mongolian population, with combined power of discrimination
of 0.999999999999999999999999998399 and
combined probability of exclusion of 0.9999999999566925.
Structure analysis showed no evidence that these nine Chinese
populations had different component distribution.
However, genetic distance analysis showed significant differences
among them (P < 0.05). Conclusion The combined application of these 22 loci
could be useful for forensic purposes in the Mongolian
population. Mongolian population had smaller genetic
distances from the populations in northern China (Northern
Han, Xinjiang Uygur, and Xinjiang Hui) than from the
populations in Hainan province (Hainan Han and Hainan
Li populations)
Improved SnO2 Electron Transport Layers Solution-Deposited at Near Room Temperature for Rigid or Flexible Perovskite Solar Cells with High Efficiencies
Electron transport layer (ETL) is a functional layer of great significance for boosting the power conversion efficiency (PCE) of perovskite solar cells (PSCs). To date, it is still a challenge to simultaneously reduce the surface defects and improve the crystallinity in ETLs during their low-temperature processing. Here, a novel strategy for the mediation of in situ regrowth of SnO2 nanocrystal ETLs is reported: introduction of controlled trace amounts of surface absorbed water on the fluorinated tin oxide (FTO) or indium-tin oxide (ITO) surfaces of the substrates using ultraviolet ozone (UVO) pretreatment. The optimum amount of adsorbed water plays a key role in balancing the hydrolysis-condensation reactions during the structural evolution of SnO2 thin films. This new approach results in a full-coverage SnO2 ETL with a desirable morphology and crystallinity for superior optical and electrical properties, as compared to the control SnO2 ETL without the UVO pretreatment. Finally, the rigid and flexible PSC devices based on the new SnO2 ETLs yield high PCEs of up to 20.5% and 17.5%, respectively
Twinning-assisted dynamic adjustment of grain boundary mobility
Grain boundary (GB) plasticity dominates the mechanical behaviours of nanocrystalline materials. Under mechanical loading, GB configuration and its local deformation geometry change dynamically with the deformation; the dynamic variation of GB deformability, however, remains largely elusive, especially regarding its relation with the frequently-observed GB-associated deformation twins in nanocrystalline materials. Attention here is focused on the GB dynamics in metallic nanocrystals, by means of well-designed in situ nanomechanical testing integrated with molecular dynamics simulations. GBs with low mobility are found to dynamically adjust their configurations and local deformation geometries via crystallographic twinning, which instantly changes the GB dynamics and enhances the GB mobility. This selfadjust twin-assisted GB dynamics is found common in a wide range of face-centred cubic nanocrystalline metals under different deformation conditions. These findings enrich our understanding of GB-mediated plasticity, especially the dynamic behaviour of GBs, and bear practical implication for developing high performance nanocrystalline materials through interface engineering
Synthesis, characterization and photodynamic therapy properties of an octa-4-tert-butylphenoxy-substituted phosphorus (V) triazatetrabenzcorrole
A novel octa-4-tert-butylphenoxy-substituted phosphorus(V) triazatetrabenzcorrole (PVTBC), has been synthesized and characterized by MALDI-TOF MS and NMR, FT-IR and MCD spectroscopy. The fluorescence emission spectrum was used to determine the fluorescence quantum yield and the quantum yield for singlet oxygen generation was calculated by using 1,3-diphenylisobenzofuran as a scavenger. The photocytoxicity against U87MG cells was measured. The results indicated that PVTBC is potentially useful as an NIR region photosensitizer for photodynamic therapy (PDT)
Current developments and future perspectives of nanotechnology in orthopedic implants: an updated review
Orthopedic implants are the most commonly used fracture fixation devices for facilitating the growth and development of incipient bone and treating bone diseases and defects. However, most orthopedic implants suffer from various drawbacks and complications, including bacterial adhesion, poor cell proliferation, and limited resistance to corrosion. One of the major drawbacks of currently available orthopedic implants is their inadequate osseointegration at the tissue-implant interface. This leads to loosening as a result of immunological rejection, wear debris formation, low mechanical fixation, and implant-related infections. Nanotechnology holds the promise to offer a wide range of innovative technologies for use in translational orthopedic research. Nanomaterials have great potential for use in orthopedic applications due to their exceptional tribological qualities, high resistance to wear and tear, ability to maintain drug release, capacity for osseointegration, and capability to regenerate tissue. Furthermore, nanostructured materials possess the ability to mimic the features and hierarchical structure of native bones. They facilitate cell proliferation, decrease the rate of infection, and prevent biofilm formation, among other diverse functions. The emergence of nanostructured polymers, metals, ceramics, and carbon materials has enabled novel approaches in orthopaedic research. This review provides a concise overview of nanotechnology-based biomaterials utilized in orthopedics, encompassing metallic and nonmetallic nanomaterials. A further overview is provided regarding the biomedical applications of nanotechnology-based biomaterials, including their application in orthopedics for drug delivery systems and bone tissue engineering to facilitate scaffold preparation, surface modification of implantable materials to improve their osteointegration properties, and treatment of musculoskeletal infections. Hence, this review article offers a contemporary overview of the current applications of nanotechnology in orthopedic implants and bone tissue engineering, as well as its prospective future applications
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