343results about How to "Avoid wrapping" patented technology

The invention discloses a WSN source position protective method based on offset angle. The method has characteristic that includes steps as follows: 1) obtaining hop count among each middle node and focus node, source node according with interest broadcast of focus node and local broadcast of source node; 2) counting offset angle value of each middle node according with hop count in step 1); 3) each source node and middle node collecting offset angle value of all adjacent middle nodes; 4) each source node and middle node counting forward probability of each adjacent middle node according with offset angle value of adjacent middle node; 5) sending information from source node to focus node through middle node and false source according with forward probability of adjacent middle node. The invention can increase security of source node for sending data.

The invention relates to the field of sustained-release fertilizers, and specifically discloses a urea-formaldehyde multi-nutrient element sustained-release fertilizer and a preparation method. The urea-formaldehyde multi-nutrient element sustained-release fertilizer comprises ammonium polyphosphate, inorganic silica gel and urea formaldehyde, wherein hydrogen bond connection can be formed betweenphosphorus-oxygen double bond of ammonium polyphosphate and a urea formaldehyde molecular chain, hydrogen bond connection can be formed between hydroxyl of inorganic silica gel and the urea formaldehyde molecular chain, and a hydrogen bond associated polymer network structure is formed among ammonium polyphosphate, inorganic silica gel and urea formaldehyde together. The urea-formaldehyde multi-nutrient element sustained-release fertilizer containing a strong hydrogen bond network structure can be prepared by using a conventional aqueous solution polymerization in combination with a normal temperature extrusion palletizing technology, a coating technology in the later period of preparing a coated fertilizer is avoided, the preparation technology is simple and effective, and a great deal of manpower and material resources are saved. According to the extrusion palletizing urea-formaldehyde multi-nutrient element sustained-release fertilizer provided by the invention, nitrogen nutrientscan be stably and sustainedly released in the whole release period, and the disadvantage that an existing urea formaldehyde fertilizer is long in nutrient release period is solved.

With a method for preparing a yarn end (9) for spinning in at a rotor spinning device (2) of a rotor spinning machine (1) with a rotor housing (3) that can be closed with a cover (4) and can be subjected to negative pressure through a negative pressure channel (8), with a spinning rotor (5) that is rotatably mounted in the rotor housing (3) and rotates with an operating rotational speed during the spinning operation along with a draw-off nozzle (7), the yarn end (9) to be prepared is introduced into the negative pressure channel (8), and is interrupted by a severing structure (10) of the open edge of the rotating spinning rotor (5), and is thereby prepared for spinning in. During the interruption of the yarn end (9), the spinning rotor (5) is driven with a defined rotational speed for the preparation of the yarn end, whereas the rotational speed for the preparation of the yarn end is either equal to the operating rotational speed of the spinning rotor (5) or is less than the operating rotational speed of the spinning rotor (5). A corresponding rotor spinning machine (1) features a control unit (17), by means of which the rotor spinning device (2) can be operated in accordance with one of the preceding claims.