Young-Tae Jeon

Differential power processing (DPP) systems are a promising architecture for future photovoltaic (PV) power systems that achieve high system efficiency through processing a faction of the full PV power, while achieving distributed local maximum power point tracking (MPPT). In the PV-to-bus DPP architecture, the power processed through the DPP converters depends on the string current, which must be controlled to minimize the power processed through the DPP converters. A real-time least power poin

Recently, the module integrated converter and differential power processing (DPP) architecture were introduced to enable the photovoltaic (PV) power conditioning system to maintain the optimal operating condition of PV cells, such as maximum power point tracking (MPPT), even under partial shading conditions. However, the DPP architecture was found to have more room to optimize the performance of the systems, by the application of an extra extremum-seeking control, the so-called least power point

Early tracheostomy reduced the MV duration, ICU LOS, and incidence of VAP in critically ill neurosurgical patients. However, early tracheostomy did not reduce either the ICU or hospital mortality.

Numerous factors are associated with mortality after hip fracture surgery in elderly patients. The aim of this study was to investigate whether preoperative C-reactive protein (CRP) was an independent risk factor for 1-year mortality after hip fracture surgery in the elderly. The electronic medical records of 772 elderly patients (age ≥ 65 years) undergoing hip fracture surgery from May 2003 to November 2011 were reviewed retrospectively. The patients comprised a high CRP group (>10.0 mg/dL) and

The intrathecal administration of clonidine 150 microg fails to prevent post-spinal shivering; by contrast, we have confirmed that i.v. clonidine 1 microg/kg is an effective method to prevent shivering in patients undergoing spinal anesthesia for orthopedic surgery.

Dendritic cells play an essential role in bridging innate and adaptive immunity by recognizing cellular stress including pathogen- and damage-associated molecular patterns and by shaping the types of antigen-specific T cell immunity. Although lidocaine is widely used in clinical settings that trigger cellular stress, it remains unclear whether such treatment impacts the activation of innate immune cells and subsequent differentiation of T cells. Here we showed that lidocaine inhibited the produc

We aimed to investigate whether statin therapy is associated with the incidence of coronavirus disease 2019 (COVID-19) among the South Korean population. In addition, we examined whether statin therapy affects hospital mortality among COVID-19 patients. The National Health Insurance Service (NHIS)-COVID-19 database in South Korea was used for data extraction for this population-based cohort study. A total of 122,040 adult individuals, with 22,633 (18.5%) in the statin therapy group and 101,697 (

This paper proposes a dc-link voltage shaping method for a cascaded H-bridge (CHB) static synchronous compensator (STATCOM). A recently proposed low capacitance-STATCOM system, which intentionally operates with large voltage ripples on the dc-link capacitors, offers the advantage of superior harmonic performance. However, the capacitor voltage ripples decrease when operating at below-rated reactive current, which removes the aforementioned harmonic performance benefit of this system. In addition

Conjunctival swelling is a common finding in patients positioned prone. The purpose of this study was to evaluate the effect of head position on postoperative chemosis after prone spinal surgery. On the basis of the head position, 108 patients scheduled for prone lumbar surgery were randomly allocated to 1 of 2 groups: head neutral group (n=54) versus head down (HD) group (n=54). Head position was defined as neutral when the imaginary line from the occipital protuberance to the top of C7 spine p

A combination of sevoflurane postconditioning and albumin increased the level of Bcl-2 expression compared with sevoflurane postconditioning or albumin alone, suggesting their combination might provide additional neuroprotection by decreasing apoptosis.

These data suggest that the orientation of the J-wire tip downward can increase successful placement rates of right subclavian venous catheterization.

A combination of preischemic dexmedetomidine and sevoflurane postconditioning provides no additional neuroprotective benefit over preischemic dexmedetomidine or sevoflurane postconditioning alone.