Abstract: Disclosed herein are a catalyst for hydrocracking reaction of high molecular weight components in bio-oil, a method for preparing the same and a method for bio-oil upgrading using the same. The catalyst includes a zeolite carrier; and at least one metal selected from the group consisting of nickel (Ni), ruthenium (Ru) and cerium (Ce) supported on the carrier. The catalyst promotes the hydrocracking of high molecular weight compounds contained in the bio-oil, but also inhibits the polymerization reaction of the decomposed product, thereby more effectively enhancing the hydrocracking reaction of the bio-oil.

Abstract: A load-sensitive automatic transmission system for an agricultural electric vehicle is provided, which includes a drive motor for generating a rotational power using electric power of a battery; a transmission for changing a rotational speed of the drive motor in multiple stages and outputting the changed rotational speed; a forward/reverse differential gear for transmitting the power of the transmission to wheels; a control unit for detecting a running state of the vehicle and a load state of the drive motor and determining a speed change time; and an actuator for operating the transmission in response to a signal from the control unit. Accordingly, it is possible to selectively provide high speed and torque to meet the needs of different situation, beyond the limitations of the motor drive performance of a conventional electric vehicle.

Abstract: A load-sensitive automatic transmission system for an agricultural electric vehicle is provided, which includes a drive motor for generating a rotational power using electric power of a battery; a transmission for changing a rotational speed of the drive motor in multiple stages and outputting the changed rotational speed; a forward/reverse differential gear for transmitting the power of the transmission to wheels; a control unit for detecting a running state of the vehicle and a load state of the drive motor and determining a speed change time; and an actuator for operating the transmission in response to a signal from the control unit. Accordingly, it is possible to selectively provide high speed and torque to meet the needs of different situation, beyond the limitations of the motor drive performance of a conventional electric vehicle.