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No greater success was achieved with the original 100mm pulse-jet engine, designed by Mr. Takeo Kimura to power the helicopter, because it proved difficult to ignite and its noise level was unacceptable.

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Research methods such as documental data, investigation, comparative analysis and mathematical statistics have been adopted in this article.

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Ecotourism have been as an ideally standard for developing area projects, while nowadays tourism is becoming the emphasis economic domain department till to the sustentacular industrial in some places.

芻議生態(tài)旅游的經(jīng)濟意義在旅游業(yè)成為許多國家或地區(qū)的重要經(jīng)濟產(chǎn)業(yè)部門乃至經(jīng)濟支柱產(chǎn)業(yè)的今天国产美女精品一区在线观看，生態(tài)旅游作為一種理想的形式，已在我國取得了一些進展91黄色毛片，并成為許多地方和部門規(guī)劃中不可缺少的項目日韩图片高清中文字幕。

Ecotourism hxdye been as an ideally standard for developing area projects, while nowadays tourism is becoming the emphasis economic domain department till to the sustentacular industrial in some places.

在業(yè)成為許多國家或地區(qū)的重要產(chǎn)業(yè)部門乃至經(jīng)濟支柱產(chǎn)業(yè)的今天，生態(tài)旅游作為一種理想的形式亚洲小12呦哟网站，已在我國取得了一些進展欧美丰满熟妇大aqq，并成為許多地方和部門規(guī)劃中不可缺少的項目。

Ecotourism have been as an ideally standard for developing area projects, while nowadays tourism is becoming the emphasis economic domain department till to the sustentacular industrial in some places.

本文由 PB創(chuàng)新網(wǎng)為您整理】在旅游業(yè)成為許多國家或地區(qū)的重要經(jīng)濟產(chǎn)業(yè)部門乃至經(jīng)濟支柱產(chǎn)業(yè)的今天官方免费黄色网，生態(tài)旅游作為一種理想的形式国产精品午夜国产小视频，已在我國取得了一些進展，并成為許多地方和部門規(guī)劃中不可缺少的項目h片欧美日韩。

Ecotourism have been as an ideally standard for developing area projects, while nowadays tourism is becoming the emphasis economic domain department till to the sustentacular industrial in some places.

在旅游業(yè)成為許多國家或地域的重要經(jīng)濟產(chǎn)業(yè)部門乃至經(jīng)濟支柱產(chǎn)業(yè)的今天成年网站在线观看播放器视频，生態(tài)旅游作為一種理想的情勢，已在我國取得了一些進展狼友视频在线观看2019高清，并成為許多地方和部門計劃中不可缺乏的項目自拍偷拍29p。

Ecotourism have been as an ideally standard for developing area projects, while nowadays tourism is becoming the emphasis economic domain department till to the sustentacular industrial in some places.

大 在旅游業(yè)成為許多國家或地區(qū)的重要經(jīng)濟產(chǎn)業(yè)部門乃至經(jīng)濟支柱產(chǎn)業(yè)的今天，生態(tài)旅游作為一種理想的形式wwwcom日韩，已在我國取得了一些進展亚洲视频色网站，并成為許多地方和部門規(guī)劃中不可缺少的項目。

In recent years, there has been a great development in such study with marvelous completions.

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