Before the spread of the Internet, everyone dealt with letters and stamps. One of the pastimes of that time was to separate the stamp from the envelope and keep it. I also had a stamp album when I was a teenager. Therefore, it is not strange that when I started my career as a welding engineer, I looked for the connection between postage stamps and welding.
The file below is the result of that effort.
PS: Unfortunately, I have not written down the references that I used.
وقتی از دی ماه ۱۴۰۲ کارم را عوض کردم و به شرکتی آمدم که در حوزهی صنایع معدنی فعالیت میکند، …
سال ۱۳۸۰ عضو یک گروه کوهنوردی شدم و آخر هفتهها در برنامههایشان شرکت میکردم… دربند، گلابدره، درکه، کلکچال، پیاز چال، …
Traditional Metal Identification Techniques
