Abstract: In a method of designing a printed circuit board, a package capacitance, a package inductance, and a chip capacitance of an actual memory device are calculated. A signal line capacitance and a signal line inductance per unit length of a signal line are calculated based on characteristics of the printed circuit board. A length of the signal line for each pin is determined based on the package capacitance and the signal line capacitance.

Abstract: Provided is a sound source signal filtering method and apparatus. The sound source signal filtering method includes: generating two or more microphone output signals by combining sound source signals input through a plurality of microphones; calculating distances between the microphones and a sound source from which the sound source signals are emitted by using distance relationships according to frequencies of the sound source signals extracted from the generated microphone output signals; and filtering the sound source signals to obtain one or more sound source signals corresponding to a predetermined distance by using the calculated distances. Accordingly, it is possible to obtain only sound source signals emitted from a sound source at a particular distance from the microphone array among a plurality of sound source signals input through the microphone array.

Abstract: An audio apparatus including a decorrelator for generating decorrelated signals by applying a phase shifting value adjusted based on a correlation difference between audio signals included in a multi-channel signal to the audio signals; and a speaker set including at least two speakers for outputting acoustic signals corresponding to the decorrelated signals

Abstract: A method and an apparatus for detecting a pitch in input voice signals by using a spectral auto-correlation. The pitch detection method includes: performing a Fourier transform on the input voice signals after performing a pre-processing on the input voice signals, performing an interpolation on the transformed voice signals, calculating a spectral difference from a difference between spectrums of the interpolated voice signals, calculating a spectral auto-correlation by using the calculated spectral difference, determining a voicing region based on the calculated spectral auto-correlation, and extracting a pitch by using the spectral auto-correlation corresponding to the voicing region.

Abstract: A sound zoom method, medium, and apparatus generating a signal in which a target sound is removed from sound signals input to a microphone-array by adjusting a null width that restricts a directivity sensitivity of the microphone array, and extracting a signal corresponding to the target sound from the sound signals by using the generated signal. Thus, a sound located at a predetermined position away from the microphone array can be selectively obtained so that a target sound is efficiently obtained.

Abstract: A method of detection of erroneous memory usage is provided. The method includes starting a computer and executing a program and a monitoring tool to collect calls to a memory during execution of the program, detecting a call to the memory using the monitoring tool, extracting lines of code which request access to a memory address via the call to the memory, detecting a set of variables to which access is granted via the call to the memory, extracting, after execution of the predetermined program, the set of variables for each of the lines of code, detecting erroneous memory usage by matching the extracted lines of code with the set of variables, and determining the call as erroneous upon access being granted to the memory corresponding to the set of variables during execution of the predetermined program when access is not possible during the execution of the program.

Abstract: Disclosed herein is a method and apparatus to recognize speech by measuring the confidence levels of respective frames. The method includes the operations of obtaining frequency features of a received speech signal for the respective frames having a predetermined length, calculating a keyword model-based likelihood and a filler model-based likelihood for each of the frame, calculating a confidence score based on the two types of likelihoods, and deciding whether the received speech signal corresponds to a keyword or a non-keyword based on the confidence scores. Also, the method includes the operation of transforming the confidence scores by applying transform functions of clusters, which include the confidence scores or are close to the confidence scores, to the confidence scores.

Abstract: A method, medium, and apparatus for extracting a target sound from a mixed sound. The method includes obtaining the mixed signal from a microphone array, generating a first signal which is emphasized and directed toward a target sound source, and a second signal which is suppressed and directed toward the target sound source, calculating a non-linear filter which is adaptive to at least one of an amplitude ratio of the first signal to the second signal in a time-frequency domain, frequencies of the first and second signals, and a ratio of an interference signal to the mixed signal, and filtering the first signal by the non-linear filter.

Abstract: A method, medium, and apparatus for extracting a target sound from mixed sound. The method includes receiving a mixed signal through a microphone array, generating a first signal whose directivity is emphasized toward a target sound source and a second signal whose directivity toward the target sound source is suppressed based on the mixed signal, and extracting a target sound signal from the first signal by masking an interference sound signal, which is contained in the first signal, based on a ratio of the first signal to the second signal. Therefore, a target sound signal can be clearly separated from a mixed sound signal which contains a plurality of sound signals and is input to a microphone array.

Abstract: Provided are an apparatus and method for estimating noise that changes with time. The apparatus may calculate a speech absence probability that indicates the possibility of the absence of speech in each frequency component of an input acoustic signal, may discriminate between a speech-dominant region and a noise region from the acoustic signals based on the speech absence probability, and may estimate noise according to the discrimination result.

Abstract: A microphone array apparatus is provided. The microphone array apparatus includes a plurality of first type microphones which are disposed to be hidden in a direction of a target source and surrounded by a cover that passes acoustic signals therethrough, and a plurality of second type microphones which are disposed at both sides of the plurality of first type microphones.

Abstract: Disclosed is a thermoplastic resin composition that includes (A) a polycarbonate resin, (B) a modified acryl-based copolymer resin, (C) a polysiloxane copolymer including an aryl group, and (D) a core-shell graft copolymer.

Abstract: An apparatus and method for tracing memory access information of a user program while ensuring a normal operation of the user program. An access permission about a memory region may be set to trace the memory access information. An instruction of the user program encounters a page fault according to the set access permission. If the page fault occurs, memory access information is stored based on the page fault, and apparatus executes an instruction causing the page fault while in a supervisor mode.

Abstract: Provided are a method and an apparatus for acquiring a multi-channel sound by using a microphone array. The method estimates positions of sound sources corresponding to sound source signals, which are mixed together, from the sound source signals input via a microphone array; and generates a multi-channel sound source signal by compensating for the sound source signals, based on differences between the estimated positions of the sound sources and a position of a virtual microphone array substituting for the microphone array. By doing so, the multi-channel sound having a stereoscopic effect can be acquired from a plurality of distant sound source signals which are input via the microphone array from a portable sound acquisition device.

Abstract: An audio quality enhancing apparatus and method is provided in which a microphone array has a non-uniform configuration and thus a beam pattern of a desired direction is obtained in a wide range of frequencies including higher frequency bands and lower frequency bands even when the microphone array is relatively small.

Abstract: One aspect of the invention relates to a methacrylate resin prepared by suspension polymerization using a polyalkylacrylate-acrylic acid as a suspension stabilizer. The suspension stabilizer is used in an amount of about 0.05 to about 0.25 parts by weight per 100 parts by weight of a monomer mixture. Another aspect of the invention relates to a method for preparing a methacrylate resin, which comprises: preparing a mixture by mixing an initiator and a chain-transfer agent with a monomer mixture comprising at least about 50% by weight of alkyl methacrylate; and adding the mixture to an aqueous solution of polyalkylacrylate-acrylic acid to conduct suspension polymerization.

Abstract: An apparatus and method for dynamically analyzing a program are provided. The apparatus and method help minimize overhead in tracing the execution of the program without substantially affecting the operation of the program at run time. The method includes storing an environment value before execution of a function of a main page by storing a first instruction of the function in a temporary page before execution of the first instruction. The method also includes inserting a break instruction at an address of the first instruction in the main page, executing the break instruction, and storing an environment value after execution of the function by executing a break instruction of the temporary page.

Abstract: Provided is a method and apparatus for canceling noise from a sound signal input through a microphone. The method includes filtering a high-frequency signal having a frequency that is higher than a reference frequency and a low-frequency signal having a frequency that is lower than the reference frequency from input signals obtained through a microphone array, obtaining a high-frequency target signal by canceling a noise signal from the filtered high-frequency signal using a beamforming method, obtaining a low-frequency target signal by canceling a noise signal having a phase difference that is different from a phase difference of a target signal from the filtered low-frequency signal, and obtaining a sound source signal from which noise is cancelled, by synthesizing the obtained high-frequency target signal with the obtained low-frequency target signal.

Abstract: A system for providing fuel-efficient driving information for a vehicle includes a fuel-efficient driving area calculation unit and a display unit. The fuel-efficient driving area calculation unit calculates a variable fuel-efficient driving area, which is divided into economical, semi-economical, and uneconomical regions, depending on the increase or decrease of the speed of the vehicle, calculates a current fuel efficiency of the vehicle, receives information about the type and condition of a road from a GPS, and adjusts the regions in the fuel-efficient driving area to prompt the driver to increase or decrease the vehicle speed in advance. The display unit displays the fuel-efficient driving area using information calculated by the fuel-efficient driving area calculation unit, and indicates the current fuel efficiency using the regions.

Abstract: An apparatus and method for removing noise are provided. The apparatus includes an acoustic signal input unit configured to comprise three or more microphones including a first microphone as a reference microphone, a second microphone disposed at a position asymmetrical to the first microphone, and a third microphone disposed at a position symmetrical to the first microphone, and an acoustic signal processing unit configured to remove rear noise using acoustic signals received from the first microphone, the second microphone, and the third microphone.