2013, Vol.18, No.5

Journal of The Korea Society of Computer and Information 2023 KCI Impact Factor : 0.65

pISSN : 1598-849X / eISSN : 2383-9945
https://journal.kci.go.kr/jksci

Smartphone enables diverse applications to be used in mobile environments. In spite of the high performance of smartphones, battery life has become one of the major constraints in mobility. Therefore, power efficiency of the smartphone is one of the most important factors in determining the efficiency of the smartphone. In this paper, in order to analyze the power efficiency of the smartphone, we have various experiments according to several configuration parameters such as processor, display and OS. We also use diverse applications. As a result, power consumption is dependent on the processor complexity and display size. However, power consumption shows the unpredictable pattern according to the OS. Smartphone using android OS consumes high power when internet and image processing applications are executed, but It consumes low power when music and camera applications are executed. In contrary, smartphone based on iOS consumes high power when game and internet applications are executed but it consumes low power when camera and processing applications are executed. In general, smartphone using iOS is more power efficient than smartphone based on android OS, because smartphone using iOS is optimized in the perspective of the hardware and OS.

This paper presents the design of the educational router system. This system is designed and implemented to support network configuration and embedded programming technology of the user on Internet. Not only Static routing protocol but also a kind of dynamic routing protocols such as OSPF and RIP and firewall have been programmed for education based on ethernet interface. ADS 1.2 as debugging environment, uC/OS-ii as RTOS and C language as development language are used. The educational procedures is compile, loading of static routing protocol, a kind of dynamic routing protocols such as OSPF and RIP and firewall program already supplied. Thereafter the verification is checked by using "ping" test to allow for demo operation such as hands-on training procedure. Finally programming procedure similar with demo operation of static routing protocol, a kind of dynamic routing protocols such as OSPF and RIP and packet filtering function is educated step by step

TIn this paper, we propose a novel fuzzy stretching method that adopts a triangle type fuzzy membership function to control the highest and lowest brightness limit dynamically. As an essential procedure to enhance the brightness contrast, stretching is an important procedure in color image processing. While popular Ends-in Search stretching method should be provided fixed minimum and maximum brightness threshold from experience, our proposed method determines them dynamically by fuzzy membership functions. The minimum and maximum limit is determined by computing the lowest and highest pixel value according to the membership degree of our designed triangle type membership function. The experiment shows that the proposed method result in far less skewed histogram than those of Ends-in Search stretching thus successfully verifies its effectiveness.