 
 	- returns: a new UUID array after union
 	*/
-	private func restructureTarget() -> [UUID]? {
+	private func unionTarget() -> [UUID]? {
 		var targets = Set<UUID>()
 		for req in self.scanRequests {
 			// if any request targets at overall scan...

		if self.scanRequests.isEmpty {
			self.centralManager.stopScan()
		} else {
			let targets = self.restructureTarget()
			self.centralManager.scanForPeripheralsWithServices(targets, options: nil)
		}
	}

	private func checkIn(request: ScanRequest) -> Void {
		self.scanRequests.insert(request)

		let targets = self.unionTarget()
		self.centralManager.scanForPeripheralsWithServices(targets, options: nil)
	}

