• The Transactions of the Korea Information Processing Society
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• v.4 no.6
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• pp.1625-1635
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• 1997

An extension of the weighted buddy system, called the extended-weighted buddy system, for dynamic memory allocation in an object-oriented computer is presented. The extended-weighted buddy system allows block sizes of $2^k,\;3*2^k,\;5*2^k,\;7*2^k$, whereas the original weighted buddy system allowed block sizes of $2^k\;and\;3*2^k$. This extension is achieved at only the cost of additional 3 bits per block for memory management unit. Simulation results are presented which compare our method with the weighted buddy system. These results indicate that, for uniform request distributions, our system has less internal memory fragmentation than the weighted buddy system(approximately 60%). And, for exponential request distributions, it has less internal memory fragmentation than the weighted buddy method (approximately 50%). The external fragmentation is greater for this system than the weighted buddy system. But, our system has less total memory fragmentation for exponential request distributions, and two systems take a similar total memory fragmentation for uniform request distributions, so we can substitutes the extended-weighted buddy system for weighted buddy system.

• The Journal of Society for e-Business Studies
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• v.8 no.2
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• pp.33-48
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• 2003

Wireless Internet, created through the merging of mobile communication with Internet technology, provides the advantage of mobility, but the restrictions of the mobile environment are deterring it from growing into a mass public service. Of the restricting factors of the wireless environment, narrow memory space creates the disadvantage of not being able to manage resources in mobile devices efficiently Because there is a limit to obtaining sufficient memory space from hardware made with consideration of portability, future devices will need to have a platform design with storage area extended from internal storage to external storage space. In this paper, we present a mobile agent that extends the memory space from only the inside of a mobile device to an external server making it possible to use data by on-line Run-time, and can also manage internal files efficiently. We have designed and implemented a RMS(Resources Management System) as a realization. Devices using the proposed RMS will be able to apply extended processes with the 'Mobile Space Extension' and will be benefited with optimal memory space through efficient internal file management.

• Proceedings of the KOSOMBE Conference
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• v.1989 no.05
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• pp.39-43
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• 1989

In this paper, hierachical representation method with a 1-to-4 and 1-to-8 data structure is used to reconstruct the three-dimensional scene from two-dimensional cross sections provided by computed tomography with small memory computer system. To reduce the internal memory use, 2-D section is represented by quadtree, and 3-D scene is represented by octree. Octree is constructed by recursively merging consecutive quadtrees. This method uses 7/200 less memory than pointer type structure with all the case, and less memory up to 60.3% than linear octree with experimental data.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.12
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• pp.2632-2640
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• 2011

In this paper, we implemented a memory controller which can accommodate data processing blocks. The memory controller is arbitrated by the internal arbiter which receives request signals from masters and sends grant and data signals to masters. The designed memory controller consists of Master Interface, Master Arbitrator, Memory Interface, Memory accelerator. It was designed using VHDL, and verified using the memory model of SAMSING Inc. For FPGA synthesis and verification, Quartus II of ATERA Inc. was used. The target device is Cyclone II. For simulation, ModelSim of Cadence Inc was used.

• Journal of KIISE:Computing Practices and Letters
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• v.8 no.1
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• pp.36-45
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• 2002

This paper introduces the design and implementation of a flash memory simulator to emulate a real flash memory. Since this simulator provides exact execution time information and parameter testing functions as well as the type, total capacity, block size, and page size of flash memory, it can be used as a real flash memory as viewed by the operating system. Furthermore, the simulator provides time logging functions of the internal routines of the flash memory management software allowing the monitoring of bottlenecks within the software. Finally, we show the performance measurements of applications under the Linux operating systems on both the simulator and a test board verifying the simulator's use as a replacement for real flash memory.

• Tuberculosis and Respiratory Diseases
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• v.63 no.4
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• pp.382-386
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• 2007

Paraneoplastic limbic encephalitis is a rare disorder that is characterized by personality changes, irritability, depression, seizures, memory loss and dementia, and is commonly associated with small cell lung cancer. The cause is unknown but it is believed to be an autoimmune disorder that develops secondary to a carcinomatous process. We report a patient with the clinical feature consistent with limbic encephalitis. A 64-year-old women developed disorientation, memory loss and general weakness. She was diagnosed with NSCLC (adenocarcinoma) with a brain metastasis 1 year earlier and was treated with radiation and chemotherapy. Although the lung mass and brain metastatic lesions had improved, the brain T2-weighted MRI showed high signal intensity in the right temporal region. This lesion consisted of with limbic encephalitis and was negative to the other viral and immune markers. The patient's symptoms did not improve after steroid treatment. Our case demonstrated that a NSCLC (adenocarcinoma) also can be associated with paraneoplastic limbic encephalitis.

• JSTS:Journal of Semiconductor Technology and Science
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• v.13 no.2
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• pp.157-169
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• 2013

Scale Invariant Feature Transform (SIFT) generates image features widely used to match objects in different images. Previous work on hardware-based SIFT implementation requires excessive internal memory and hardware logic [1]. In this paper, a new hardware organization is proposed to implement SIFT with less memory and hardware cost than the previous work. To this end, a parallel Gaussian filter bank is adopted to eliminate the buffers that store intermediate results because parallel operations allow all intermediate results available at the same time. Furthermore, the processing order is changed from the raster-scan order to the block-by-block order so that the line buffer size storing the source image is also reduced. These techniques trade the reduction of memory size with a slight increase of the execution time and external memory bandwidth. As a result, the memory size is reduced by 94.4%. The proposed hardware for SIFT implementation includes the Descriptor generation block, which is omitted in the previous work [1]. The addition of the hardwired descriptor generation improves the computation speed by about 30 times when compared with the previous work.

• IEMEK Journal of Embedded Systems and Applications
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• v.8 no.5
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• pp.235-242
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• 2013

Recently, the number of automotive electrical and electronic system has been increased because the requirements for the convenience and safety of the drivers and passengers are raised. In most cases, the data for controlling the various sensors and automotive electrical and electronic system used in runtime should be stored on the internal or external non-volatile memory of the ECU(Electronic Control Units). However, the non-volatile memory has a constraint with write limitation due to the hardware characteristics. The limitation causes fatal accidents or unexpected results if the non-volatile memory is not managed. In this paper, we propose a management scheme for using non-volatile memory to prolong the writing times based on AUTOSAR(AUTOmotive Open System Architecture) platform. Our proposal is implemented on the CDD(Complex Device Driver) and uses an algorithm which swaps a frequently modified block for a least modified block. Through the development of the prototype, the proposed scheme extends the lifetime of non-volatile memory about 1.08 to 2.48 times than simply using the AUTOSAR standard.

• Korean Journal of Biological Psychiatry
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• v.22 no.2
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• pp.63-77
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• 2015

Objectives The combination extract of four kinds of herbs, Gastrodia elata, Liriope platyphylla, Dimocarpus longan, and Salvia miltiorrhiza, has shown to have memory improving effects in mice. The aim of this study was to investigate the efficacy and safety of the herbal mixture for improving working memory as well as microstructural changes in white matter integrity in individuals with subjective memory complaints. Methods Seventy-five individuals with subjective memory complaints were assigned to receive either placebo (n = 15) or herbal mixture (low-dose group, n = 30 and high-dose group, n = 30) supplementation in an 8-week, randomized, double-blind, placebo-controlled clinical trial. Changes in working memory performance and fractional anisotropy (FA) values reflecting white matter integrity from baseline to 8-week endpoint were assessed. Results The herbal mixture group showed an increase in working memory performance compared to the placebo group (p for interaction = 0.001). In addition, the herbal mixture group showed an increase in FA values in the temporo-parietal regions (corrected p < 0.05), which are crucially involved in working memory function and are among the most affected regions in patients with cognitive impairments. Conclusions Findings from this study indicate that the herbal mixture may be a promising therapeutic option for individuals with subjective memory complaints.

• Transactions of Materials Processing
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• v.19 no.8
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• pp.468-473
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• 2010

Shape memory alloys (SMAs) have the ability to recover their original shape upon thermo-mechanical loading even after large inelastic deformation. The unique feature is known as pseudoelasticity and shape memory effect caused by the crystalline structural transformation between two solid-state phases called austenite and martensite. To support the engineering application, a number of constitutive models, which can be formally classified into either micromechanics-based or phenomenological model, have been developed. Most of the constitutive models include a kinetic law governing the crystallographic transformation. The present work presents a one-dimensional, phenomenological constitutive model for SMAs in the context of the unified viscoplasticity theory. The proposed model does not incorporate the complex mechanisms of phase transformation. Instead, the effects induced by the transformation are depicted through the growth law for the back stress that is an internal state variable of the model.