<?php

// Start store emulation process
/**
* @var Mage_Core_Model_App_Emulation $appEmulation
*/
$appEmulation = Mage::getSingleton('core/app_emulation');
$initialEnvironmentInfo = $appEmulation->startEnvironmentEmulation($storeIdToEmulate);

try {

	// .... logic which have to be in store env proceed

} catch (Exception $e) {
    Mage::logException($e);
    // do not forget stop emulation if some error happens
    $appEmulation->stopEnvironmentEmulation($initialEnvironmentInfo);
    throw $e;
}

// at the and of our logic - stop emulation
$appEmulation->stopEnvironmentEmulation($initialEnvironmentInfo);