The electric vehicle charging business basically consists of the operation of charging infrastructure and charging services for electric vehicle users, and each individual system is developed and provided for these charging business services. As the charging business becomes active, new business needs such as failure management and diagnosis of charging infrastructure are emerging, and to address and service these new business needs, we are responding by developing individual systems tailored to each business needs. Meanwhile, OCPP(Open Charge Point Protocol) is actually used as a standard communication protocol in charge point communication, and in Korea, separate non-standard communication protocols are used by charging business operators, so chargers that do not support the communication protocol cannot provide the business service. This paper provides a standardized interface with charging business services regardless of charge point communication protocol and proposes an electric vehicle charging business service platform based on OCPP that can easily add and expand various new charging business services such as electric vehicle demand response, and smart charging.

Acetabular reamers used in total hip arthroplasty serve as removing the damaged acetabular. The processing performance of the reamer needs to be improved so that the artificial joint can be properly mounted on the surgical site. In this study, reaming simulations and experiments were conducted to improve the machining performance of the reamer. It is possible to shorten the prototype production period through the precision casting method by applying the 3D printing technique. As a result, various prototypes could be produced in a short period of time according to the size change of the reamer, and it greatly contributed to the improvement of the processing performance of the reamer.

In this study, the components of propionic acid, formic acid, coumarinic acid and gibberellic acid were extracted from the bamboo vinegar by vacuum distillation. The components of bamboo vinegar increased with increasing temperature of distillation. The amount of components extracted from bamboo vinegar were follow order : propionic acid > formic acid > gibberellic acid > coumarinic acid. In the bamboo vinegar extraction process, the estimated values for the free energy of Gibbs (△G°) were positive, which indicated that a nonspontaneous process. Among the components of bamboo vinegar, propionic acid and formic acid were confirmed to have a bacterial growth inhibitory effect for pseudomonas aeruginosa.

Lamium purpureum is widely distributed in Europe, Africa, and Asia based on its rapid reproduction and high survival rate, and is also found in domestic pastures, gardens, and cultivated land. In this study, L. purpureum was extracted with methanol and fractionated into hexane, ethyl acetate, and butanol, and experiments were conducted on total phenol, total flavonoid, antioxidant, NO production inhibitory activity, and cytotoxicity. The total phenol, total flavonoid, and antioxidant activity of L. purpureum are shown in the order of butanol fraction, methanol extract, ethyl acetate fraction, water fraction, and hexane fraction. The NO production inhibitory activity showed the highest inhibitory effect in the ethyl acetate fraction, and 4.2% inhibitory activity was confirmed in the butanol fraction for cytotoxicity, and cytotoxicity was not observed in other samples. Through this experiment, the physiological activity of L. purpureum was verified, and it is expected that it will become a basic data that can be used in future studies.

In the current and future mobile communication networks, the cell size is reduced to increase the efficiency of the radio channels and to cope with the ever-increasing number of subscribers and high-speed services. In this study, we propose a new handover call control method called HDF (Handover Duration First) to serve a handover call with the smallest handover duration first in consideration of the directionality in the handover area among queued handover calls. In order to analyze the performance of the proposed HDF method, simulation is performed to obtain the blocking probabilities of new and handover calls when new and handover calls are generated and compared with the existing FIFO (First In First Out) method. Simulation results show that the proposed HDF method has better performance from the viewpoint of blocking probability and forced termination probability than the conventional method. The results of this study can contribute to various studies to increase the efficiency of handover on radio channels.

This study was undertaken to evaluate the mixed light-emitting diode (LED) module for dental care, which promotes cell regeneration. To evaluate the mixed LED module (634 nm + 860 nm), human gingival fibroblast (HGF-1) was irradiated on the mixed LED light at 0 and 12 h after cell scratch. The wound area was observed in 0, 6, 12, 24, 48 h. As a result, the mixed LED light irradiation affected wound healing. When the mixed wavelength of 634 nm + 860 nm was irradiated for 400 s, the highest wound area reduction rate was confirmed. In this study, the mixed LED light irradiation was only different irradiation time. However, each group showed a different wound area reduction rate. In conclusion, this study confirmed that the fastest wound healing effect when it was irradiated with mixed LED for 400 second on human gingival fibroblast. Through the study results, light irradiation time should be considered for the mixed LED light irradiation wound healing effect. In order to more accurately verify the wound healing effect of the mixed LED light irradiation, it will be necessary to compare each wavelength of light (634 nm or 860 nm) using HGF-1 cells.

Virtual, which is used to indicate an imaginary situation or object that does not exist in reality, intends to verify molding analysis, product manufacturing, and 3D measurement for application in the automotive industry. Through analysis verification, the formability of product data is verified in advance, problems are found and improved at an early stage, and the work flow of modeling work and forming analysis verification (formability, thickness reduction rate, spring back, etc.) is carried out. After that, after securing formability based on the results of mold production and TRY OUT molding analysis, after completing the production for each mold process, in order to proceed under the same conditions as the molding analysis conditions, the final TRY OUT for each process is performed by optimizing the press line and mold nurturing. do. Finally, it was seated in the inspection area and high-speed 3D scanning was performed to compare and analyze the previously verified molding analysis results and 3D scan results to confirm the objective accuracy.

The luminous efficiency of a light emitting diode based semiconductor light source applied as a flexible display and lighting source is a very important characteristic. In order to improve the luminous efficiency, various research methods including light emitting and current injection layers have been proposed. However, since this efficiency improvement is based on a planar structure, it is difficult to improve the optical properties. In this study, the nano-patterned column integrated structures were formed through the reactive etching process. In addition, a semiconductor light source having a light emitting structure by depositing multi-quantum well layers on the nano-sized column structure can be realized through the etched nano frame and hole structure.

In this paper, we propose the current canceling variable gain amplifier (VGA) using a regulated cascode topology that reduces the output phase error between maximum voltage gain state and minimum voltage gain state. Since the output phase variation is inversely proportional to the transconductance of the common gate transistor, the regulated cascode topology can help reduce phase variation and thus phase error by increasing the transconductance of CG transistor. The proposed VGA is implemented in 65 nm CMOS and exhibits 13.8 dB maximum voltage gain, 20 dB voltage control range, 2.9 degree phase error over 25.8 GHz~32.5 GHz 3-dB bandwidth, and 1.28 degree phase error at the center frequency of 29.5 GHz.