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在3 kHz至300 GHz頻率下測(cè)量射頻場(chǎng)的準(zhǔn)則檢測(cè)項(xiàng)目報(bào)價(jià)？??解決方案？??檢測(cè)周期？??樣品要求？ |
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本標(biāo)準(zhǔn)規(guī)定了為保存和發(fā)行而進(jìn)行縮微拍攝報(bào)紙的一般原則。它包括對(duì)標(biāo)板的要求，以確保正確的著錄和保證縮微品符合存檔的相關(guān)標(biāo)準(zhǔn)。本標(biāo)準(zhǔn)適用于35 mm無孔縮微卷片或縮微條片，包括第一代縮微膠片、中間片和發(fā)行拷貝。
GB/T 29306的本部分規(guī)定了絕緣材料介電性能的試驗(yàn)方法。本部分適用于測(cè)定微波頻率范圍(即從約300 MHz一直到光頻)中介質(zhì)材料的相對(duì)電容率、介質(zhì)損耗因數(shù)和與此有關(guān)的量,如損耗指數(shù)。
GB/T 29306的本部分規(guī)定了以諧振法測(cè)定絕緣材料介電性能的試驗(yàn)方法。 本部分適用于以諧振法測(cè)定微波頻率范圍(即從約300MHz一直到光頻)中固體、液體或熔融狀介質(zhì)材料的相對(duì)電容率、介質(zhì)損耗因數(shù)和與此有關(guān)的量,如損耗指數(shù)。
This method describes procedures applying to solid plastics insulating materials for the determination of permittivity and dissipation factor and of quantities calculated from them, such as loss index, within the frequency range 15 Hz to 300 MHz. Some of the procedures described can, with special precautions, be used for measurements at frequencies considerably lower or higher than the given limits.The calculations and measurements given are based on sinusoidal waveform.Fusible materials, as well as solid materials, can be measured by the pro-cedures described. The measured values are dependent on physical conditions such as frequency, temperature and moisture content, and in special cases, on field strength as well.In some cases, tests at voltages exceeding 1000 V may introduce effects not related to permittivity and dielectric dissipation factor, and are not described herein.NOTES:1. Some considerations affecting choice of measuring methods are given in Appen-dix A.2. Measuring apparatus and their use are discussed in Appendix B.3. The significance of dielectric properties is discussed in Appendix C.4. Factors influencing dielectric measurements are considered in Appendix D.5. The accuracy to be expected from the test procedures and circuits is discussed in Appendix E.
Applies to the procedures for the determination of relative permittivity and dielectric dissipation factor of dielectric materials in the microwave frequency region. This part of the standard gives general definitions, contains a discussion of the factors influencing dielectric properties of dielectric materials, a survey on measuring methods and requirements for test material shape and quantity.
Details with reference to the general considerations in part 1 of this standard the measuring procedures of the dielectric properties of insulating materials at microwave frequencies by resonance methods. In an appendix following resonator types are described: Re-entrant cavity resonators (frequency range 100 MHz to 1000 MHz), coaxial resonators ( 1 GHz to 7 GHz), resonant cavities ( 1 GHz to 30 GHz), \"open\" cavity resonators (above about 3 GHz, for solid specimens of low dissipation factor only) and optical resonators (above about 30 GHz).
This practice outlines dosimetric procedures to be followed in\ninstallation qualification (IQ), operational qualification (OQ) and\nperformance qualifications (PQ), and routine processing at electron\nbeam facilities. \nThe electron beam energy range covered in this practice is\nbetween 300 keV and 25 MeV, although there are some discussions for\nother energies. \nDosimetry is only one component of a total quality assurance\nprogram for adherence to good manufacturing practices used in\nradiation processing applications. Other measures besides dosimetry\nmay be required for specific applications such as health care\nproduct sterilization and food preservation. \nSpecific standards exist for the radiation sterilization of\nhealth care products and the irradiation of food. For the radiation\nsterilization of health care products, see ISO 11137-1\n(Requirements) and ISO 11137-3 (Guidance on dosimetric aspects).\nFor irradiation of food, see ISO 14470. In those areas covered by\nthese stand
This Recommendation provides guidance on indoor propagation over the frequency range from 300 MHz to100 GHz. Information is given on:path loss models;delay spread models;effects of polarization and antenna radiation pattern;effects of transmitter and receiver siting;effects of building materials furnishing and furniture;effects of movement of objects in the room;statistical model in static usage.
As the bands 3 400-4 200 MHz and 4 500-4 800 MHz are allocated worldwide on a primary basis to the FSS, this Report presents the results of the sharing studies performed between the FSS networks using the geostationary satellite orbit (GSO) and IMT-Advanced systems.
The frequency band 35.5-36 GHz is allocated to the EESS (active), space research (active), radiolocation and meteorological aids services on a primary basis. Although the 35.5-36 GHz band is allocated for meteorological aids, there is no known use of the band by this service
The ITU Radiocommunication Assembly considering that the earth stations of various different geostationary (GSO) satellite networks in the fixed-satellite service (FSS) are planning to commence operation in the 30 GHz frequency range in the near future.
The ITU Radiocommunication Assembly considering that the earth stations of various different geostationary (GSO) satellite networks in the fixed-satellite service (FSS) are planning to commence operation in the 30 GHz frequency range in the near future.
This Recommendation concerns the system operation for a conference call between three or moreaudiovisual terminals. It is applicable to a single MCU containing an audio mixer and a videoswitch according to the provisions of ITU-T Rec. H.231, to calls involving two such MCUs, and tocalls involving three or more MCUs in a star configuration. It is also applicable to MCUscontaining a video mixer. ITU-T Recs H.233 and H.234 address issues concerning the use of theEncryption Control Signal (ECS). ITU-T Rec. H.242 provides for communication between twoaudiovisual terminals connected point to point, using the frame structure defined in ITU-TRec. H.221. ITU-T Rec. H.230 defines a number of Control and Indication signals, including thoseused in the multipoint communication procedures described in this Recommendation.Three or more audiovisual terminals may be put into communication to form a conference call, bymeans of one or more Multipoint Control Units (MCU). The general principles of multipointcommunication are described in ITU-T Rec. H.231. The means by which digital channels areestablished between terminals and MCUs, and between MCUs, is outside the scope of thisRecommendation (see ITU-T Rec. H.200/AV.420).It should be noted that the physical realization of an MCU may be such that two or moreindependent conferences may be set up within the same unit; logically, however, there is norelationship between these conferences; the text herein refers to an MCU only as a logical entitypertinent to the particular call of concern.This Recommendation concerns only the flow of signals along the fixed digital paths, which may beat 64 kbit/s (56 kbit/s in certain networks) or multiples thereof up to 1920 kbit/s. The flow consistsof a multiplex of audio, video, control and indication signals, and optional user data as defined inITU-T Rec. H.221 which must be handled by the MCU in a way which is satisfactory to the users.The signal multiplex on each path is fully in accordance with ITU-T Rec. H.221: the BAScommands define explicitly how the demultiplexer at the end of each link shall operate. Likewise,the basic procedures for initialization and mode switching are fully in accordance with thosedefined in ITU-T Rec. H.242 for point-to-point working. However, the composition of themultiplexed signal transmitted by each terminal and by the MCU is determined by terminalprocedures and multipoint system procedures, as follows:a) Terminal procedures are defined in service-specific system Recommendations, such asITU-T Rec. H.320 for visual telephony.b) Multipoint system procedures are defined in this Recommendation and are not ofthemselves service-specific.c) ITU-T Rec. T.120: by making use of the T series, MCU and terminal procedures may begreatly enhanced, offering far more sophisticated specific applications to the user. Suchenhancement is outside the scope of this Recommendation, although interactions withspecific T.120 methods are described here.For definitions of terms used in this Recommendation, see ITU-T Rec. H.231; for definitions ofSBE and MBE symbols, see ITU-T Rec. H.230.
1.1 This practice covers dosimetric procedures to be followed in facility characterization, process qualification, and routine processing using electron beam radiation to ensure that the entire product has been treated with an acceptable range of absorbed doses. Other procedures related to facility characterization (including equipment documentation), process qualification, and routine product processing that may influence and may be used to monitor absorbed dose in the product are also discussed. Note 18212;For guidance in the selection and calibration of dosimeters, see ISO/ASTM Guide 51261. For further guidance in the selection, calibration, and use of specific dosimeters, and interpretation of absorbed dose in the product from dosimetry, also see ASTM Practice E 668 and ISO/ASTM Practices 51275, 51276, 51431, 51607, 51631, and 51650. For use with electron energies above 5 MeV, see ASTM Practice E 1026, and ISO/ASTM Practices 51205, 51401, 51538, and 51540 for discussions of specific large volume dosimeters. For discussion of radiation dosimetry for pulsed radiation, see ICRU Report 34. When considering a dosimeter type, be cautious of influences from dose rates and accelerator pulse rates and widths (if applicable).1.2 The electron energy range covered in this practice is between 300 keV and 25 MeV, although there are some discussions for other energies. 1.3 Dosimetry is only one component of a total quality assurance program for an irradiation facility. Other controls besides dosimetry may be required for specific applications such as medical device sterilization and food preservation.1.4 For the irradiation of food and the radiation sterilization of health care products, other specific ISO standards exist. For food irradiation, see ISO/ASTM Practice 51431. For the radiation sterilization of health care products, see ISO 11137. In those areas covered by ISO 11137, that standard takes precedence.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
