• JSTS:Journal of Semiconductor Technology and Science
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• v.16 no.3
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• pp.300-311
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• 2016

The analog-to-digital-converter-based (ADC-based) backplane receivers that consist of a front-end ADC followed by a digital equalizer are gaining more popularity in recent years, as they support more sophisticated equalization required for high data rates, scale better with fabrication technology, and are more immune to PVT variations. Unfortunately, designing an ADC-based receiver that meets tight power and performance budgets of high-speed backplane link systems is non-trivial as both front-end ADC and digital equalizer can be power consuming and complex when running at high speed. This paper reviews the state of art designs for the front-end ADC and digital equalizers to suggest implementation choices that can achieve high speed while maintaining low power consumption and complexity. Design-space exploration using system-level models of the ADC-based receiver allows through analysis on the impact of design parameters, providing useful information in optimizing the power and performance of the receiver at the early stage of design. The system-level simulation results with newer device parameters reveal that, although the power consumption of the ADC-based receiver may not comparable to the receivers with analog equalizers yet, they will become more attractive as the fabrication technology continues to scale as power consumption of digital equalizer scales well with process.

• ETRI Journal
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• v.26 no.6
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• pp.555-559
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• 2004

We propose an efficient digital IF down converter architecture for dual-mode WCDMA/cdma2000 based on the concept of software defined radio. Multi-rate digital filters and fractional frequency conversion techniques are adopted to implement the front end of a dual-mode receiver for WCDMA and cdma2000. A sub-sampled digital IF stage was proposed to support both WCDMA and cdma2000 while lowering the sampling frequency. Use of a CIC filter and ISOP filter combined with proper arrangement of multi-rate filters and common filter blocks resulted in optimized hardware implementation of the front end block in 292k logic gates.

• Journal of electromagnetic engineering and science
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• v.16 no.4
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• pp.241-247
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• 2016

This paper proposes the design and measurement of a 6-18 GHz front-end receiver module that has been combined into a one- channel output from a two-channel input for electronic warfare support measures (ESM) applications. This module includes a limiter, high-pass filter (HPF), power combiner, equalizer and amplifier. This paper focuses on the design aspects of reducing the noise figure (NF) and matching the phase and amplitude. The NF, linear equalizer, power divider, and HPF were considered in the design. A broadband receiver based on a combined configuration used to obtain low NF. We verify that our receiver module improves the noise figure by as much as 0.78 dB over measured data with a maximum of 5.54 dB over a 6-18 GHz bandwidth; the difference value of phase matching is within $7^{\circ}$ between ports.

• Korean Journal of Computational Design and Engineering
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• v.14 no.2
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• pp.105-114
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• 2009

A design needs various experience and design knowledge through a whole design process. Despite of all efforts and time, it is not easy to introduce a product that meets all customer's needs and expectation in time. To achieve the product goal, designers need a set of sequential process to find appropriate design parameters and ensure customers' needs and requirements. In this research we propose a design methodology for the initial design of an excavator front group with existing QFD(Quality Function Deployment) and Axiomatic Design to satisfy customer's requirements. It turns out that the proposed methodology can support designers more effectively, objectively, and systematically.

• International Journal of Automotive Technology
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• v.6 no.5
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• pp.491-499
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• 2005

There are different types of vehicle impacts recorded every year, resulting in many injuries and fatalities. The severity of these impacts depends on the aggressivety and incompatibility of vehicle-to-roadside hardware impacts. The aim of this paper is to investigate and to enhance crashworthiness in the case of full barrier impact using a new idea of crash improvement. Two different types of smart structures have been proposed to support the function of the existing vehicle. The work carried out in this paper includes developing and analyzing mathematical models of vehicle-to-barrier impact for the two types of smart structures. It is proven from analytical analysis that the mathematical models can be used in an effective way to give a quick insight of real life crashes. Moreover, it is shown that these models are valid and flexible, and can be useful in optimization studies.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.11a
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• pp.23-24
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• 2021

Since 2011, apartment houses account for about 41% of the fires in residential facilities for the past 10 years. Fire-resistant performance of fire doors is becoming more important to prevent the spread of fire in apartment houses. This research analyzed the structure of fire door through each 10 DB based on the quality inspection report of Continuous Acquisition & Life-cycle Support(CALS) from 2016 to 2020, which passed the fire performance test based on the laws and notices of domestic fire door. Therefore, based on the results of the analysis of DB in the future, we will conduct a study on structural improvement and addition for fireproof performance improvement of fire door.

• The Journal of Natural Sciences
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• v.5 no.2
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• pp.25-32
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• 1992

Statistical database(SDB) are large database primarily collected for purpose of statistical analysis. Commerical database management systems have not been widely used for SDB because of the efficiency problem of storage and access of those systems for SDB. In this paper, we propose SDB management method to use a front-end system to a Relatianal Datebase Management System (RDBMS). We do the design of SM-F system (Stasticical database Management as Front-end system) as a front-end system to a RDBMS. In the system, we use GROS model specially proposed for SDB, and store and manage summary database and meta database to support statistical analysis and to provide users with statistical summary information.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.22 no.12
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• pp.2834-2851
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• 1997

In this paper, a design and implementation of VHDL compiler front-end, aims at supporting the full-set of VHDL '87 & '93 LRM and carring out the preprocessing of VHDL-to-C, is described. The VHDL compiler front-end includes 1)the symbol tree of analyzed data to represent the hierarchy, the scope and visibility, the overloading and homograph, the concurrent multiple stacks in VHDL, 2)the data structure and supportig routies to deal with the objects, the type and subtype, the attribute and operation in VHDL, 3)the analysis of the concurrent/sequential statements, the behavior/structural descriptions, of semantic token and the propagation of symbol & type to improve the registration and retrieval procedure of analyzed data. In the experiments with Validation Suite, the VHDL compiler front-end could support the full-set specification of VHDL LRM '87 & '93; and in the experiments to asses the performance of symantic token for the VHDL hierachy/visibility/concurrency/semantic checking, the improvement of about 20-30% could be achieved.

• The Journal of the Convergence on Culture Technology
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• v.5 no.3
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• pp.345-349
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• 2019

In Korea, the mountainous area occupies more than 70% of the whole country, cutting of earth slope that cuts a part of the ground surface is widely used when building infrastructures such as road, railroad, and industrial complex construction. In recent years, regulations on environmental damage have become more strict, and various methods have been developed and applied. Among them, Concrete-Panel Retaining Wall technique is actively applied. Concrete-Panel Retaining Wall is a method to resist horizontal earth pressure by forming a wall by attaching a precast retaining wall to the front of the support material and increasing the shear strength of the disk through reinforcement of the support material. Soil nailing, earth bolt, and ground anchor are used as support material. Among them, ground anchor is a more aggressive reinforcement type that introduces tensile load in advance to the steel wire, and a large concentrated load acts on the front panel. This concentrated load is a factor that creates cracks in the concrete panel and reduces the durability of the retaining wall itself. In this study, steel pipe sleeves and reinforcements were purchased at the anchorage of the panel to prevent cracks, and by applying bumpy shear keys to the end of the panel, the weakness of the individual behavior of the existing grout anchors was improved. The problem of degraded landscape by exposure to front concrete of retaining wall and protrusion of anchorage was solved by the production of natural stone patterns and the construction of sections that do not protrude the anchorage. In order to verify the effectiveness of anti-crack sleeves and reinforcements used in the null, indoor testing and three-dimensional numerical analysis have been performed, and the use of steel pipe sleeves and reinforcements has demonstrated the overall strength increase and crack suppression effect of panels.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.12
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• pp.1-9
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• 2020

As pet dogs rapidly increase in number, abandoned and lost dogs are also increasing in number. In Korea, animal registration has been in force since 2014, but the registration rate is not high owing to safety and effectiveness issues. Biometrics is attracting attention as an alternative. In order to increase the recognition rate from biometrics, it is necessary to collect biometric images in the same form as much as possible-from the face. This paper proposes a method to determine whether a dog is facing front or not in a real-time video. The proposed method detects the dog's eyes and nose using deep learning, and extracts five types of directional face information through the relative size and position of the detected face. Then, a machine learning classifier determines whether the dog is facing front or not. We used 2,000 dog images for learning, verification, and testing. YOLOv3 and YOLOv4 were used to detect the eyes and nose, and Multi-layer Perceptron (MLP), Random Forest (RF), and the Support Vector Machine (SVM) were used as classifiers. When YOLOv4 and the RF classifier were used with all five types of the proposed face orientation information, the face recognition rate was best, at 95.25%, and we found that real-time processing is possible.