Most of the portable systems, such as cellular communication devices, and laptop computers operate from a limited power supply. Devices like cell phones have long idle times and operate in standby mode when not in use. Consequently, the extension of battery-based operation time is a significant design goal which can be made possible by controlling the leakage current flowing through the CMOS gate. This article reviews the off-state leakage mechanisms like weak inversion leakage, gate induced drain leakage and channel punchthrough current. Various circuit level techniques to reduce standby leakage and their design trade-off are discussed. Based on the surveyed techniques, a designer would be able to select the appropriate leakage optimization technique for a standby mode.

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India is an agriculture-oriented country. For the quality and productivity improvement of greenhouse crops, it is necessary to measure and control several interacting physical variables. These tasks can only be accomplished by 'control systems with built in software'. Erecting greenhouse is expensive. Automation machinery is imported in India hence it is expensive. Many farmers cannot adopt the greenhouse technology due to its high cost. The paper highlights about the approach to control the environment in Greenhouse. The greenhouse controller senses the changes in the temperatures (Dry temperature, Wet temperature) through input sensors and processes to take control action.Facilities are provided to the user so that settings can be changed by keyboard and messages can be displayed on the LCD display. Relay outputs for FAN-PAD, FOGGER, LAMP, VENTS can be activated in Normal or Cyclic or Scheduled operating mode. Thus effort is taken to reduce the automation product cost using FPGA.

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After 1994, highway bridges are maintained under the Special Law on Structure Safety in Korea. To keep a structure good condition, inspection of the structure has to be performed periodically. The inspection is hard work and needs a lot of time and many inspectors to inspect the structure that is important or damaged. Generally, this contains subjectivity of inspector, and so the result of inspection is not objective and reliable. And the inspection has a limit to only the bridges that access is possible to bottom of it. The purpose of this study is to develop new inspection technique and equipment to solve above problems and to provide convenient inspection work. The new inspection method may be able to make the inspection of bridge deck more efficient and reliable. This new inspection technique makes inspection job scientific and systematic. Digital image processing technology and Robotics are used in this inspection system. This study can be divided into three parts. 1) A study on development of digital image processing system. This system can stitch each image and detect cracks of bottom of bridge deck. Also, it can extract an investigation drawing from the picture. 2) Development of remote controlled robot system with camera and boom system. Pictures of bottom of bridge deck can be captured easily by using robot controlled on the deck remote. 3) A study on construction of Database of digital images obtained by remote controlled robot system. We can compare the pictures obtained periodically. So we can find changes of surface and crack propagations from the images. As a result of this study, inspection work with naked eye could replace with the new inspection system. The system is manufactured including digital camera module, remote controlled robot, boom system and vehicle, and global positioning system.