However, a pilot can only choose to fly IFR if they possess an instrument rating which is above and beyond the basic pilot's license that must also be held.

然而，如果飞行员持有的仪器等级在其必须持有的基本的飞行员执照等级之上，那么飞行员只能选择仪表飞行规则。

The difference between Class E and A airspace is that in Class A, all operations are IFR, and pilots must be instrument-rated, that is, skilled and licensed in aircraft instrumentation.

E 级和 A 级空域的区别在于，在 A 级空域，所有操作都需遵照仪表飞行规则，飞行员必须要有仪表等级，也就是说，要有操作航空仪表方面的技术和执照。

On a clear day, a pilot in controlled airspace can choose a VFR or IFR flight plan, and the FAA regulations were devised in a way which accommodates both VFR and IFR operations in the same airspace.

在晴天，在管制空域内的飞行员可以选择目视飞行规则或者仪表飞行规则的飞行计划，而且联邦航空局的条例是以这样一种方式设计的：在同一空域同时适用目视飞行规则和仪表飞行规则的操作。

IR analysis showed that IFR was in the form of cycle-type structure.

红外分析表明该阻燃剂具有环状结构。

Cellulose diacetate(CDA) is not effective flame-retarded synergistic agent of IFR.

二乙酸纤维素不是IFR有效的阻燃协效剂。

The synergism of zeolite in selfmade intumescent flame retardant(IFR) was studied.

考察了分子筛在自制膨胀型阻燃体系（IFR）中的协效催化作用。

VFR night flight and IFR flight under visual conditions are also said to be possible.

VFR夜间飞行和IFR目视条件下飞行同样也是许可的。

IASC has enacted IAS34 "interim financial reporting" on 2,1998, it is the fist time that IASC enact standard on IFR.

国际会计准则委员会（IASC）于1 998年2月发布了第34号国际会计准则（IAS）“中期财务报告” ，这是IASC首次就中期财务报告问题发布准则。

However, poor compatibility between IFR and polymer matrix leads to some deterioration of mechanical property of materials.

尽管如此，阻燃剂与聚合物间较差的相容性使阻燃聚合物力学性能有所劣化。

BusDriver: probably the same time on a holding pattern (or perhaps a bit less). Over the 45 minutes for IFR reserves though.

大概同时进入等待航线（排队）吧（或者稍晚点儿）。高于IFR要求的45分钟时间。

The results showed that the use of PA6 improved the apparent viscosity, mechanical properties and thermostability of IFR-PP.

结果表明：PA6的加入提高了IFR PP的表观粘度、力学性能和热稳定性。

IFR GPS-101 global positioning system simulator of the global positioning system (GPS) to provide accurate and continuous test.

IFR GPS - 101全球定位系统模拟器对全球定位系统(GPS)提供精确和连续的测试。

The effect of intumescent flame retardant(IFR)on the combustion and smoke of low-density polyethylene(LDPE)was studied by cone calorimeter.

用锥形量热法研究了膨胀型阻燃剂对低密度聚乙烯燃烧和发烟性能的影响。

SEM observation revealed that puffy coking charred layers were formed by lots of closed bubbles in ABS specimen filled with IFR after burning.

扫描电子显微镜观测发现，经IFR阻燃的ABS在燃烧时形成了由无数封闭孔洞构成的蓬松焦化炭层，表明IFR对ABS具有良好的膨胀阻燃效果。

Flame retardation of EVA copolymer using melamine phosphate (MP) and pentaerythritol (PER) as intumescent flame retardants (IFR) was investigated.

研究了三聚氰胺磷酸盐(M P)和季戊四醇(PER)作为膨胀型阻燃剂(ifr)在乙烯-醋酸乙烯酯共聚物(EVA)中的阻燃作用。

This paper firstly discusses the concept and peculiarities of the Internet Financial Report(IFR), puts forward that there are three levels of IFR;

本文首先探讨了网络财务报告的概念与特点，提出网络财务报告有三个层次；

Influence of IFR on behavior of carbonization, microstructure, flame resistance, mechanical properties and processability of ABS composites were studied.

研究了IFR对ABS炭化行为、微观结构、阻燃性能、力学性能及加工性能的影响。

DEPARTURE control, a function of an approach control facility providing air traffic control service for departing IFR and, under certain conditions, VFR aircraft.

离场控制，给用仪表飞行规则离场，和在某种情况下用目视飞行规则离场的飞机提供空中交通管制服务的进近管制设施的一种功能。

Intumescent flame retardant (IFR) has attracted more interest recently. The late progress the synthesis, application of pyrolysis dynamics of IFR has been reported frequently.

近年来膨胀型阻燃剂(ifr)的研究受到普遍关注，在IFR的合成、应用以及热分解动力学等方面取得了一定进展。

CONTROLLED airspace, an airspace of defined dimensions within which air traffic control service is provided to IFR flights and to VFR flights in accordance with the airspace classification.

受管制空域，一个范围明确的空域。在该空域内，仪表飞行规则飞行和目视飞行规则飞行有空中交通管制服务。

The comprehensive performance of the flame retardant plastics can be improved through surface treatment, microcapsule and synergistic flame retardant of IFR as well as applied using trinity-IFR.

磷氮类膨胀型阻燃剂(ifr)阻燃塑料存在着吸湿性大、热稳定性和相容性差等缺点，通过对ifr的表面处理、微胶囊化、协同阻燃以及使用“三位一体”型ifr可以减低上述缺点，提高膨胀阻燃塑料的综合性能。