One of the difficulties with PWM switching converters is high switching loss and electromagnetic interference due to switching at non-zero voltage and current, which limits the operating frequency. In order to reduce the converter volume and weight (by increasing the frequency) and reducing switching losses, zero voltage and current switching methods are recommended. In this paper, four main ze...

The paper proposes a novel interleaved AC-DC ZCS-PWM boost converter that requires the use of just single active auxiliary switch to assist in turning off main power circuit switches with ZCS. can be turned on and ZCS its allows operate without an increase peak current or voltage stress. is for much shorter time than most other converter, which at higher levels previously proposed switch. conve...

Eighty attempts at placing suction catheters in the left main bronchus were analysed by studying chest radiographs. When angled catheters were used via a tracheostomy tube the success rate was 75%; the rate fell to 15% when straight tubes were used through an orotracheal tube. Assessment and control of the tube length was found to be important to avoid kinking and subsequent obstruction of the ...

We present an interesting case of a complete vanishing of the left main bronchus in a lung transplant recipient who had a successful outcome due to acute respiratory support with venovenous extracorporeal membrane oxygenation in order to perform airway dilation.

In this paper, a QR flyback converter using self-driven active snubber (SDAS) was proposed to solve the problem of voltage surge in switch converters. converter, SDAS consisting clamping capacitor and an can be configured parallel with main or transformer reduce switch. To confirm steady-state characteristics which is applied, equivalent circuits for each state were constructed, equations deter...

BACKGROUND The loss of a normal airway is devastating. Attempts to replace large airways have met with serious problems. Prerequisites for a tissue-engineered replacement are a suitable matrix, cells, ideal mechanical properties, and the absence of antigenicity. We aimed to bioengineer tubular tracheal matrices, using a tissue-engineering protocol, and to assess the application of this technolo...

The term "fallen lung sign" refers to the collapsed lung in a dependent position, hanging on the hilum only by its vascular attachments. This is usually the result of the complete rupture of a bronchus. On chest radiograph, the diagnosis of bronchial tear is usually suspected with the persistence of a pneumothorax after chest tube insertion. An 8-year-old male patient had radiographic findings ...

In children, it has been shown that the angles of the tracheobronchial bifurcation total approximately 80 degrees; the overall mean of the right bronchial angle is about 30o, while the left bronchial angle is about 50o. This tracheobronchial relationship may explain why the tracheal tube is more likely to enter the more vertical and wider right main stem bronchus than the more obliquely placed ...

A novel ZVZCS isolated dual series-resonant active-clamp dc–dc converter is proposed to obtain high efficiency. The proposed converter employs an active-clamp technique, while a series-resonant scheme controls the output voltage with the complementary pulse width modulation controller. The active-clamp circuit serves to recycle the energy stored in the leakage inductance or the magnetizing ...

In this paper, we are discuss about the issue of synchronization for singular complex dynamical networks with Markovian jumping parameters and additive time-varying delays through pinning control by Takagi-Sugeno (T-S) fuzzy theory.The complex dynamical systems consist of m nodes and the systems switch from one mode to another, a Markovian chain with glorious transition probabili...