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var img1on = new Image();
img1on.src = "http://www.ietf76.jp/images/01000-access_on.gif"; 
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img1off.src = "http://www.ietf76.jp/images/01000-access.gif";

var img2on = new Image();
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img2off.src = "http://www.ietf76.jp/images/02000-network.gif";

var img3on = new Image();
img3on.src = "http://www.ietf76.jp/images/03000-general_on.gif"; 
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img3off.src = "http://www.ietf76.jp/images/03000-general.gif";

var img4on = new Image();
img4on.src = "http://www.ietf76.jp/images/04000-dining_on.gif"; 
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img4off.src = "http://www.ietf76.jp/images/04000-dining.gif";

var img5on = new Image();
img5on.src = "http://www.ietf76.jp/images/05000-attractions_on.gif"; 
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img5off.src = "http://www.ietf76.jp/images/05000-attractions.gif";

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img6off.src = "http://www.ietf76.jp/images/06000-special_events.gif";

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img8off.src = "http://www.ietf76.jp/images/08000-outline.gif";

var img9on = new Image();
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img10off.src = "http://www.ietf76.jp/images/10000-sponsors.gif";
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function On(name) { 

if (document.images) { 
document.images[name].src = eval(name + 'on.src'); 
} 

} 


function Off(name) { 

if (document.images) { 
document.images[name].src = eval(name + 'off.src'); 
} 

}