10 Matching Annotations
  1. Sep 2022
    1. Taking carbon steel as an example, as shown in Picture 1, using a 1000w fiber laser cutting machine, for carbon steel materials thickness below 10mm, when the thickness of carbon steel is less than 2mm, the cutting speed per minute can be up to 8 meters. When the thickness is 6mm, the cutting speed is about 1.6 meters per minute, and when the thickness of the carbon steel is 10 mm, the cutting speed is about 0.6 to 0.7 meters per minute.

      Taking carbon steel as an example, as shown in Picture 1, using a 1000w fiber laser cutting machine, for carbon steel materials thickness below 10mm, when the thickness of carbon steel is less than 2mm, the cutting speed per minute can be up to 8 meters. When the thickness is 6mm, the cutting speed is about 1.6 meters per minute, and when the thickness of the carbon steel is 10 mm, the cutting speed is about 0.6 to 0.7 meters per minute.

      • Taking carbon steel as an example, as shown in Picture 1, using a 1000w fiber laser cutting machine, for carbon steel materials thickness below 10mm, when the thickness of carbon steel is less than 2mm, the cutting speed per minute can be up to 8 meters. When the thickness is 6mm, the cutting speed is about 1.6 meters per minute, and when the thickness of the carbon steel is 10 mm, the cutting speed is about 0.6 to 0.7 meters per minute.

      It can be seen that when the thickness of carbon steel material is less than 2mm, customers who attach great importance to cutting speed can consider using 2000W fiber laser cutting machine, but the 2000W machine is much higher than 1000W in equipment price and operating cost. When the carbon steel material is larger than 2mm, the 2000W machine is not much faster than the 1000W cutting speed. Therefore, the 1000W fiber laser cutting machine is more cost-effective than the 2000W fiber laser cutting machine.

      The cutting speed can directly reflect the efficiency of the fiber laser cutting machine. For cutting different materials with different thickness, the cutting speed will also change greatly. The thicker the thickness, the slower the speed!

  2. Feb 2021
  3. Oct 2020
  4. Jul 2020
  5. Mar 2020
    1. Factors that affect power

      Factors that affect power.

    2. Cohen’s recommendations:  Jacob Cohen has many well-known publications regarding issues of power and power analyses, including some recommendations about effect sizes that you can use when doing your power analysis.  Many researchers (including Cohen) consider the use of such recommendations as a last resort, when a thorough literature review has failed to reveal any useful numbers and a pilot study is either not possible or not feasible.  From Cohen (1988, pages 24-27):

      Recommendations from Cohen about choosing the effect size when doing a power analysis.

    3. Obtaining the necessary numbers to do a power analysis

      Obtaining the necessary numbers to do a power analysis

    4. Power is the probability of detecting an effect, given that the effect is really there.  In other words, it is the probability of rejecting the null hypothesis when it is in fact false.  For example, let’s say that we have a simple study with drug A and a placebo group, and that the drug truly is effective; the power is the probability of finding a difference between the two groups.  So, imagine that we had a power of .8 and that this simple study was conducted many times.  Having power of .8 means that 80% of the time, we would get a statistically significant difference between the drug A and placebo groups.  This also means that 20% of the times that we run this experiment, we will not obtain a statistically significant effect between the two groups, even though there really is an effect in reality.

      Power analysis definition