• Title/Summary/Keyword: power-space functions

Search Result 139, Processing Time 0.026 seconds

Measurement and Modeling of Personal Exposure to the Electric and Magnetic Fields in the Vicinity of High Voltage Power Lines

  • Tourab, Wafa;Babouri, Abdesselam
    • Safety and Health at Work
    • /
    • v.7 no.2
    • /
    • pp.102-110
    • /
    • 2016
  • Background: This work presents an experimental and modeling study of the electromagnetic environment in the vicinity of a high voltage substation located in eastern Algeria (Annaba city) specified with a very high population density. The effects of electromagnetic fields emanating from the coupled multi-lines high voltage power systems (MLHV) on the health of the workers and people living in proximity of substations has been analyzed. Methods: Experimental Measurements for the Multi-lines power system proposed have been conducted in the free space under the high voltage lines. Field's intensities were measured using a referenced and calibrated electromagnetic field meter PMM8053B for the levels 0 m, 1 m, 1.5 m and 1.8 m witch present the sensitive's parts as organs and major functions (head, heart, pelvis and feet) of the human body. Results: The measurement results were validated by numerical simulation using the finite element method and these results are compared with the limit values of the international standards. Conclusion: We project to set own national standards for exposure to electromagnetic fields, in order to achieve a regional database that will be at the disposal of partners concerned to ensure safety of people and mainly workers inside high voltage electrical substations.

Hangul Porting and Display Performance Comparison of an Embedded System (임베디드 시스템을 위한 한글 포팅 및 출력 성능 비교)

  • Oh, Sam-Kweon;Park, Geun-Duk;Kim, Byoung-Kuk
    • Journal of Digital Contents Society
    • /
    • v.10 no.4
    • /
    • pp.493-499
    • /
    • 2009
  • Three methods frequently used for Hangul display in computer systems are Standard Johab Code in which each of Hangul consonants and vowels is given a 5-bit code and each syllable created by combining them forms a 2-byte code, Standard Wansung Code in which each of all the syllables generally used for Hangul presentation forms a 2-byte code, and Unicode in which each syllable in most of the world's language systems is given a unique code so that it allows computers to consistently represent and manipulate them in a unified manner. An embedded system in general has a lower processing power and a limited amount of storage space, compared to a personal compute(PC) system. According to its usage, however, the former may have a processing power equal to that of the latter. Hence, when Hangul display needs to be adopted, an embedded system must choose a display method suitable for its own resource environment. This paper introduces a TFT LCD initialization method and pixel display functions of an LN2440SBC embedded board on which an LP35, a 3.5" TFT LCD kit, is attached. Using the initialization and pixel display functions, in addition, we compare three aforementioned Hangul display methods, in terms of their processing speeds and amounts of memory space required. According to experiments, Standard Johab Code requires less amount of memory space but more processing time than Standard Wansung Code, and Unicode requires the largest amount of memory space but the least processing time.

  • PDF

Estimation of CME 3-D parameters using a full ice-cream cone model

  • Na, Hyeonock;Moon, Yong-Jae
    • The Bulletin of The Korean Astronomical Society
    • /
    • v.42 no.2
    • /
    • pp.62.1-62.1
    • /
    • 2017
  • In space weather forecast, it is important to determine three-dimensional properties of CMEs. Using 29 limb CMEs, we examine which cone type is close to a CME three-dimensional structure. We find that most CMEs have near full ice-cream cone structure which is a symmetrical circular cone combined with a hemisphere. We develop a full ice-cream cone model based on a new methodology that the full ice-cream cone consists of many flat cones with different heights and angular widths. By applying this model to 12 SOHO/LASCO halo CMEs, we find that 3D parameters from our method are similar to those from other stereoscopic methods (i.e., a triangulation method and a Graduated Cylindrical Shell model). In addition, we derive CME mean density (${\bar{\rho}_{CME}}={\frac{M_{total}}{V_{cone}}}$) based on the full ice-cream cone structure. For several limb events, we determine CME mass by applying the Solarsoft procedure (e.g., cme_mass.pro) to SOHO/LASCO C3 images. CME volumes are estimated from the full ice-cream cone structure. For the first time, we derive average CME densities as a function of CME height for several CMEs, which are well fitted to power-law functions. We will compare densities (front and average) of geoeffective CMEs and their corresponding ICME ones.

  • PDF

Analysis of Solar Microwave Burst Spectrum, I. Nonuniform Magnetic Field

  • Lee, Jeongwoo
    • Journal of Astronomy and Space Sciences
    • /
    • v.35 no.4
    • /
    • pp.211-218
    • /
    • 2018
  • Solar microwave bursts carry information about the magnetic field in the emitting region as well as about electrons accelerated during solar flares. While this sensitivity to the coronal magnetic field must be a unique advantage of solar microwave burst observations, it also adds a complexity to spectral analysis targeted to electron diagnostics. This paper introduces a new spectral analysis procedure in which the cross-section and thickness of a microwave source are expressed as power-law functions of the magnetic field so that the degree of magnetic inhomogeneity can systematically be derived. We applied this spectral analysis tool to two contrasting events observed by the Owens Valley Solar Array: the SOL2003-04-04T20:55 flare with a steep microwave spectrum and the SOL2003-10-19T16:50 flare with a broader spectrum. Our analysis shows that the strong flare with the broader microwave spectrum occurred in a region of highly inhomogeneous magnetic field and vice versa. We further demonstrate that such source properties are consistent with the magnetic field observations from the Michelson Doppler Imager instrument onboard the Solar and Heliospheric Observatory (SOHO) spacecraft and the extreme ultraviolet imaging observations from the SOHO extreme ultraviolet imaging telescope. This spectral inversion tool is particularly useful for analyzing microwave flux spectra of strong flares from magnetically complex systems.

Data reduction package for the Immersion Grating Infrared Spectrograph (IGRINS)

  • Sim, Chae Kyung;Le, Huynh Anh Nguyen;Pak, Soojong;Lee, Hye-In;Kang, Wonseok;Chun, Moo-Young;Jeong, Ueejeong;Yuk, In-Soo;Kim, Kang-Min;Park, Chan;Jaffe, Daniel T.;Pavel, Michael
    • The Bulletin of The Korean Astronomical Society
    • /
    • v.38 no.2
    • /
    • pp.84.1-84.1
    • /
    • 2013
  • We present a python-based data reduction pipeline for the Immersion GRating INfrared Spectrograph (IGRINS). IGRINS covers the complete H- and K-bands in a single exposure with a spectral resolving power of greater than 40,000. IGRINS is designed to be compatible with telescopes of diameters ranging from 2.7-m (the Harlan J. Smith telescope at McDonald Observatory) to 8-10m. Commissioning and initial operation will be on the 2.7-m telescope from late 2013. The pipeline package is a part of the IGRINS software and designed to be compatible with other package that maneuvers the spectrograph during the observation. This package provides high-quality spectra with minimal human intervention and the processes of order extraction, distortion correction, and wavelength calibration can be automatically carried out using the predefined functions (e.g. echellogram mapping and 2D transform). Since the IGRINS is a prototype of the Giant Magellan Telescope Near-Infrared Spectrometer (GMTNIRS), this pipeline will be extended to the GMTNIRS software.

  • PDF

A Study on the Facility and Equipment of Laboratory Medicine in General Hospital - Focused on less than three hundred bed hospitals (종합병원 진단검사의학과 검사실의 시설 현황 조사 - 300 병상 미만 병원을 중심으로)

  • Kim, Youngaee
    • Journal of The Korea Institute of Healthcare Architecture
    • /
    • v.25 no.3
    • /
    • pp.15-23
    • /
    • 2019
  • Purpose: As the medical laboratories in general hospitals have made an efforts on quality management and employee health, they recognized the need of design guideline for clinical laboratory. As laboratories are prohibited to patients, their environments are becoming more congested and deteriorated as time goes by. So, this study investigates the current status of facility and equipment of laboratory medicine focusing on less than three hundred patient bed hospitals, and searches the improving matters. Methods: Questionnaires to technologist captains and field surveys to medical laboratories in korean hospitals have been conducted for the data collection. 18 answers have been analysed statistically by MS Excel program. Results: The result of this study can be summarized into followings. Clinical laboratory functions are all hematology, clinical chemistry, immunology, transfusion and urine microscopy, and except for three including microbiology for infection and bio safety level. Average man power of lab are 12.3 man including lab director and captain. Patient bed number, space area and total specimen numbers are not correlated with each other, but specimen numbers and employee number are correlated with. Work space distances are usually good, but exit distances are not adequate for escape owing to obstacles. Specimen delivery system by courier, test method by automatic analyzer, access floor for exposed plumbing and electricities are more practical. Open lab layed out in the center and lab support layed peripheral in space diagram. Lab space configuration by SD method showed that lab support area and employee support area are dissatisfied. Implications: Specialized hospital and yearly total specimen numbers are related to the space area and organization for laboratory planning and design.

FPGA Implementation of Doppler Invarient Low Power BFSK Receiver Using CORDIC (CORDIC을 이용한 도플러 불변 저전력 BFSK 수신기의 FPGA구현)

  • Byon, Kun-Sik
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.12 no.8
    • /
    • pp.1488-1494
    • /
    • 2008
  • This paper is to design and implement a low power noncoherent BFSK receiver intended for future deep space communication using Xilinx System generator. The receiver incorporates a 16 point Fast Fourier Transform(FFT) for symbol detection. The design units of the receiver are digital design for better efficiency and reliability. The receiver functions on one bit data processing and supports main data rate 10kbps. In addition CORDIC algorithm is used for avoiding complex multiplications while computing FFT and multiplication of twiddle factor for low power is substituted by rotators. The design and simulation of the receiver is carried out in Simulink then the Simulink model is translated to the hardware model to implement FPGA using Xilinx System Generator and to verify performance.

A variational nodal formulation for multi-dimensional unstructured neutron diffusion problems

  • Qizheng Sun ;Wei Xiao;Xiangyue Li ;Han Yin;Tengfei Zhang ;Xiaojing Liu
    • Nuclear Engineering and Technology
    • /
    • v.55 no.6
    • /
    • pp.2172-2194
    • /
    • 2023
  • A variational nodal method (VNM) with unstructured-mesh is presented for solving steady-state and dynamic neutron diffusion equations. Orthogonal polynomials are employed for spatial discretization, and the stiffness confinement method (SCM) is implemented for temporal discretization. Coordinate transformation relations are derived to map unstructured triangular nodes to a standard node. Methods for constructing triangular prism space trial functions and identifying unique nodes are elaborated. Additionally, the partitioned matrix (PM) and generalized partitioned matrix (GPM) methods are proposed to accelerate the within-group and power iterations. Neutron diffusion problems with different fuel assembly geometries validate the method. With less than 5 pcm eigenvalue (keff) error and 1% relative power error, the accuracy is comparable to reference methods. In addition, a test case based on the kilowatt heat pipe reactor, KRUSTY, is created, simulated, and evaluated to illustrate the method's precision and geometrical flexibility. The Dodds problem with a step transient perturbation proves that the SCM allows for sufficiently accurate power predictions even with a large time-step of approximately 0.1 s. In addition, combining the PM and GPM results in a speedup ratio of 2-3.

Soft decision for Gray Coded PAM Signals Using Max-Log-MAP (Max-Log-MAP을 이용한 Gray 부호화된 PAM 신호의 연판정 계산식)

  • Hyun, Kwang-Min;Yoon, Dong-Weon
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.31 no.2C
    • /
    • pp.117-122
    • /
    • 2006
  • In this paper, we present a simple and general soft bit decision expression for a Gray coded PAM signal over additive white Gaussian noise(AWGN) channel with the log likelihood ratio(LLR). In order to reduce the complexity of the LLR calculation, we make the bitwise LLR expression simple by replacing the mathematical max functions of the conventional Max-Log-MAP expression with simple arithmetic functions associated with some deterministic parameters, such as a received value and distance between symbols on a signal space. Taking the implementation issues, like the area of silicon, the power consumption, the timing latency, and so on, into consideration, we submit that the proposed method is a promising alternative way to conventional methods for reconfigurable systems.

A study on the Architectural Condition and Cases of BIPV-module for Roof (지붕일체형 PV모듈의 건축특성 및 적용사례 분석연구)

  • Lee, Eung-Jik
    • KIEAE Journal
    • /
    • v.6 no.3
    • /
    • pp.49-56
    • /
    • 2006
  • The roof among the outer surfaces of buildings is an optimum place to install PV since it is the best favorable part in the building to be exposed to day light. Especially, in case of module of BIPV for Roof, it should have essentially the functions of both electricity generation and roof-finish as a construction material. The followings are the results of the study which has analyzed the architectural conditions and applications thereof at the job site. -The aesthetic function of BIPV module is very important because the roof, mostly located at the top of the buildings, is easily recognized and affects outer interior design of the building a lot. -The heat proof of BIPV for Roof could affect the energy consumption through the roof having a wide area. -For architectural condition to the weather, the roof has to ensure the stability of the weather, humidity proof, and airtightness to the wind respectively. -For architectural condition of the structure, endurance by physical power such as stability of both combining and fixing and transfer of load should be ensured. -For residents protection, it has also architectural functions to secure for the space and shield ozone, UV and noxious substances. -Through its practical applications, It is already confirmed that there are various types of BIPV modules overseas and its application has been proved successfully.