Saturday, December 24, 2022

Thoughts on Dart Mission.


I was just thinking that if you put a massive electric charge on an asteroid it should want to spread out. Causing the rocks and dust to electrostatically repel.

While creating opposite charges should make the 2 asteroids attract each other. 

Friday, December 09, 2022

Overboard - hoverboard robot

Project Overboard. A robot that simulates a rider by going over an unmodify hoverboard. Hence Overboard.

Monday, May 02, 2022

1995 Internet presentation


1995 Presentation I put together. 

TDK Internet presentation


While researching the question “What is the Internet?” to provide a simple unbiased answer to the question., I came across many widely different explanations of what the Internet really is.


So what does the word internet really mean? The term “Internet” is abbreviated from “Inter-Networking”


As defined by Webster’s New World Dictionary

                Inter- prefix          1. between or among.  

                                                2. with or on each other [interact]

                Networking           1. the development of contacts or exchanging of information

                                                2. the interconnection of computer systems.


Networking or a network describes the interconnections between computers as opposed to the computers themselves and what could be accomplished by connecting them. There are two major terms use to describe computer networks, the LAN or local area network is what is commonly found in offices. It can tie an office of PC’s and MACs together to allow sharing a printer, disk space, maybe a CDROM drive, or e-mail.

Beyond this is a WAN or wide area network , this can be used to connect several mainframe locations or several office LANs together . This Internet is the ultimate a collection of interconnected WAN’s connecting over 10,000 LAN’s together, it is a global network of networks.


Buddha came up with a good definition approx. 2500 Years ago

"As a net is made up of a series of ties, so everything in this world is connected by a series of ties.  If anyone thinks that the mesh of a net is an independent, isolated thing, he is mistaken.  It is called a net because it is made up of a series of interconnected meshes, and each mesh has its place and responsibility in relation to other meshes."


Another definition given in "The Whole Internet User's Guide and Catalog,"

The Internet can be thought about in relation to its common protocols, as a physical collection of routers and circuits, as a set of shared resources, or even as an attitude about interconnecting and intercommunication.

Some common definitions given in the past include:

                * a network of networks based on the TCP/IP protocols,

                * a community of people who use and develop those networks,

                * a collection of resources that can be reached from those

The Internet as a single network is incomprehensible hugh. The physical network itself  has 4 Million computers world wide with 32 Million people using it. It uses fiber optics, satellite links, packet radio , microwave, free space laser, modems over phone lines, leased lines T1, T3, ISDN, ATM Frame relay, SNA ethernet X.25 and many other types of communications. One of the biggest reasons for the internets success is it’s adaptability, anywhere two computers can communicate the internet can expand out to. The network it’s self has almost become a living creature taking on a life of it’s own, made up of many different organizations and companies and that have agreed to join networks, it is owned by everyone on it, and has become a public resource. But the physical part of this global network is only a small part of what it really represents.  The Internet has become a tightly nit global community in cyberspace, it offers just about everything you can find in a big city like New York and more. It has news papers, mail, billboards, malls, markets, libraries, friends, and a lot of gossip, and much more.


Understanding how this came to be will require looking how it has evolved. 


In the Early 1960’s in the RAND corporation ,  Americas' foremost Cold War think-tank was faced with a problem. How to make a communications network that could withstand a nuclear attack?  Any traditional network at that time was like the phone company with central command and control location, should a problem occur with the control center the entire systems would stop. In 1964 Paul Baran made public a plan for a network that would have no Central authority and was designed to operate with major parts of  it destroyed.   The principles are simple. The network is assumed to be unreliable at all times, and it is designed to work around section that are not working. Each machine (node) on the network has equal authority to every other node. The messages passed between nodes are broken smaller pieces called packets. Each packet contains the address of were it is going  and checksum to verify that it is still correct. The nodes on the network pass each packet along in the direction of it final destination until it get there. The path that these packet take may be different for each and it is possible that a packet may get lost, copied , or arrive in a different order than it was sent. It is the responsibility of  the destination node to collect and organize these packets back into the original message and ask for missing packets if any don't arrive after a certain period of time. 


 This concept was then funded  in 1969 by the Pentagon’s Advanced Research Projects Agency(ARPA) to connect several supercomputers around the country, it was called the ARPANET.  Initially the NCP or Network Control Protocol was used. A protocol describes the way these computers on the network communicate with one another, make decisions and resolve problems together. NCP was then replaced with an improved protocol called TCP/IP or Transmission Control Protocol / Internet Protocol. One of the major things about TCP/IP is it makes no assumption about what type of connection it’s being used over. TCP/IP is what allow the internet to go everywhere, It is one of the only .protocols that will work for both a LAN and a WAN.  


Over the years the number of computers joining this network grew rapidly. One of the most popular uses of this network became E-Mail, But this was limited to only those who could afford the expense of special leased lines to directly connect to the Elite of the ARPANET.  As a solution for those less fortunate to receive E-Mail a method was devised in 1976. Using the UUCP (Unix to Unix Copy Program) to pass E-Mail along from UNIX machine to UNIX machine over standard phone lines using modems. This uses a store and forward method and was slow and complicated, but it did extend the reach of E-Mail. This became known as the USENET and although it is not a part of the Internet it has played a vital role in the Internets development.   Machines called Gateways have been established that allow Mail, News and  even file transfers to pass between the Internet and other networks like the USENET, but these external networks are not using TCP/IP and are not a part of the internet. The totality of these combined networks is called the Matrix.


In 1982 - 1983 the ARPANET officially switch to TCP/IP from NCP. The TCP/IP protocols are public-domain and with the released of BSD UNIX version 4.2  from Berkeley a cheap reliable operating systems became available with full TCP/IP support. BSD UNIX came will full source code allowing people to port this operating systems and networking tools to almost every type of computer made at the time. All the networking software was free and it was almost impossible to stop people from just connecting up to the internet.


Universities around the country were linking together and installed Ethernet across there campuses. Ethernet is a LAN networking standard that originally used a 1/2 round bright orange cable run through ceilings. It was very simple to plug into this cable get instant high speed access to almost every computer in every university around the world.  The demand for this was enormous. After a point most college and universities offered free shell account to it student and faculty.  A shell account is an account on a UNIX machine that allow you run TCP/IP program on that machine and see the results over a terminal. Soon people were able to call from home and check there E-Mail, move large files or use a computer on the other side of the country that they had moved away from just like they were sitting in front of it. With access to such a powerful system, students started developing more software for the internet most of it public-domain.  As these student left the demand to use these services from home and business brought about many private companies that did nothing else but offer University like shell account onto UNIX machines. Netcom is one of the biggest of these. As the price  of modems dropped and the speeds became higher new things became possible. One of these is SLIP

The MATRIX - Real Time (Internet) VS Store and Forward (UUCP)


On the global network there are two major types of connections that make up the MATRIX,real time and store and forward.  A real time connection is also known as a direct internet connection. All Internet services are fully available and instantaneous.  Store and forward connection on the other hand are much slower and only support a small number of services, E-Mail, Netnews, and File transfer. E-mail on a store and forward network, can take between 2 hours to 2 days to get through.


There are many store and forward networks the biggest being UUCP (Unix to Unix Copy Program) based, most commonly called the USENET  The way these networks operate is mail or news is in the form of files saved on a hard disk. At regular intervals each machine on the network (that are not really connected) calls it’s neighboring machines using a modem and exchanges files. Mail on a network like this might have to pass along half a dozen machines (NODES) before reaching it’s destination. This network also connects into the Internet and often mail might start on the USENET be passed along to the Internet and then end up back on the USENET.


One of the main driving forces for store and forward networks is it’s cheap. It is only recently that inexpensive high speed modems are available for $200 allowing speeds almost as fast as $1000 a month.  Only a few years ago the top speed available over a phone line was 2400 Baud and shortly before that only 300 Baud. And here where a store and forward network really makes sense. A letter might take 2 Minutes to send at such slow data rates and the cost of sending it long distance would add up. But on a UUCP network most nodes are a local phone call and after hopping several nodes would be able to reach the Internet back bone and rocket across the world to it’s destination.  So this provides a cheap method for extending the internets reach, But it’s not really the Internet.


With todays high speed modems, real time internet has become practical and inexpensive over a standard phone line. Using SLIP (Serial line internet protocol) or PPP (point to point protocol) all internet services are available.

It’s only recently have high speed modem become available

Most online providers are in the Matrix, Compuserve, prodigy etc, But there are NOT on the Internet and can only move E-Mail and maybe NetNews. 


                                Xerox Park  - Ethernet

                                BSD UNIX- TCP/IP

                                E-MAIL & NEWS





                                NII - National Information Infrastructure - Info Super highway

                                SSL - Secure socket layer- Electronic Cash & Electronic commerce.

                                Wireless and Cable TV

                How to get in on it

                                Slip - PPP - ISDN - T1 - T3

                                Service providers.



                What's available?

                                Applications - Matrix  (ON REAL-TIME)

                                                E-MAIL, NEWS

                                Applications - Internet  (REAL-TIME)

                                                FTP, TELNET, FINGER, WHOIS

                                                GOPHER, ARCHIE, Veronica, Jughead, WAIS

                                                MU, IRC

                                                WWW - Mosaic - Netscape.


                Why would TDK be interested


                                Public relations


                                Customer Support

                                Direct Sales

                                Technical literature.



                                Research (business , marketing, technical, academic)

                                Public Domain software - utilities

                                Job recruitment

                                Customer feedback

                                FREE Technical Advice and assistance


                                Employee handbook

                                memo's - saving paper

                                improved internal communications and workflow

                                improved corporate organization


.      hierarchy

History Darpa - Arpanet Internet Timeline



Going through my old CD backup and found this I wrote in 3/1995 

History Darpa - Arpanet

Internet Timeline



1957   USSR launches Sputnik, first artificial earth satellite.  In response,

       US forms the Advanced Research Projects Agency (ARPA) within the

       Department of Defense (DoD) to establish US lead in science and

       technology applicable to the military


1962   Paul Baran, RAND: "On Distributed Communications Networks"

         - Packet-switching networks; no single outage point


1966   the Information Processing Techniques Office (IPTO) of ARPA

       appointed Larry Roberts to develop the packet-switching wide-area

       computer network;


1967    ACM Symposium on Operating Principles

        - Plan presented for a packet-switching network


1968    Network presentation to the Advanced Research Projects Agency (ARPA)


1969    ARPANET commissioned by DOD for research into networking

        - use of Information Message Processors (IMP) [Honeywell mini computer

          with 12K of memory] developed by Bolt Beranek and Newman (BBN)

          a four-node initial configuration of the ARPANET was in place. 50Kbps

          UCLA, SRI, UCSB, U of Utah,


        First Request for Comment (RFC): "Host Software" by Steve Crocker


1970    ALOHAnet packet radio network developed by Norman Abrahamson, U of



        ARPANET hosts start using Network Control Protocol (NCP).


1971    15 nodes (23 hosts): UCLA, SRI, UCSB, U of Utah, BBN, MIT, RAND, SDC,

        Harvard, Lincoln Lab, Stanford, UIU(C), CWRU, CMU, NASA/Ames


1972    International Conference on Computer Communications with

        demonstration of ARPANET between 40 machines organized by Bob Kahn.


        InterNetworking Working Group (INWG) created to address need

        for establishing agreed upon protocols.  Chairman: Vinton Cerf.


        Ray Tomlinson of BBN invents E-Mail program to send messages across a

        distributed network.


1973    First international connections to the ARPANET: England and Norway


        Bob Metcalfe's (founder of 3COM) PhD Thesis outlines idea for Ethernet


1974    Vint Cerf and Bob Kahn publish "A Protocol for Packet Network

        Internetworking" which specified in detail the design of a

        Transmission Control Program (TCP).


        BBN opens Telenet, commercial version of ARPANET

         (used mostly to connect to Compuserve)


1975    Operational management of Internet transferred to DCA (now DISA)


        "Jargon File", by Raphael Finkel at SAIL, first released tested


1976    UUCP (Unix-to-Unix CoPy) developed at AT&T Bell Labs and distributed

        with UNIX one year later.


1977    THEORYNET created at U of Wisconsin providing electronic mail to

        over 100 researchers in computer science (using uucp).


        TCP over world wide satellite links and packet radio.


1978    Final draft of TCP released


1979    Meeting between U of Wisconsin, DARPA, NSF, and computer scientists

        from many universities to establish a Computer Science Department

        research computer network.


        USENET established using uucp between Duke and UNC by Tom Truscott

        and Steve Bellovin. Providing News and E-Mail services


1980    Berkeley releases 4.0 BSD UNIX


1981    BITNET, the "Because Its Time NETwork"

        - Started as a cooperative network at the City University of New York.

        - Provides electronic mail and listserv servers to distribute


        - Unlike USENET, where client s/w is needed, electronic mail is the

          only tool necessary.


        CSNET (Computer Science NETwork) built by UCAR and BBN through seed

        money granted by NSF to provide networking services (specially

        E-Mail) to university scientists with no access to ARPANET.  CSNET

        later becomes known as the Computer and Science Network.


        Minitel (Teletel) is deployed across France by French Telecom.


1982    INWG establishes the Transmission Control Protocol (TCP) and Internet

        Protocol (IP), as the protocol suite, commonly known as TCP/IP, for


        - This leads to one of the first definition of an "internet"

          as a connected set of networks, specifically those using TCP/IP,

          and "Internet" as connected TCP/IP internets.

        - DoD declares TCP/IP suite to be standard for DoD


        EUnet (European UNIX Network) is created by EUUG to provide E-Mail and

        USENET services.


1983    Name server developed at U of Wisconsin, no longer requiring users

        to know the exact path to other systems.


        Cutover from NCP to TCP/IP (1 January)


        CSNET / ARPANET gateway put in place


        ARPANET split into ARPANET and MILNET; the latter became integrated

        with the Defense Data Network created the previous year.


        Berkeley releases 4.2 BSD UNIX incorporating TCP/IP standard.


        Desktop workstations come into being, many with Berkeley UNIX which

        includes IP networking software.


        Need switches from having a single, large time sharing computer

        connected to Internet per site, to connection of an entire LAN.


        EARN (European Academic and Research Network) established.  Very

        similar to the way BITNET works.


        FidoNet developed by Tom Jennings.


1984    Domain Name Server (DNS) introduced.


        # of hosts breaks 1,000


        JUNET (Japan Unix Network) established using UUCP.



        JANET (Joint Academic Network) established in the UK using the

        Coloured Book protocols.

1986    NSFNET created (backbone speed of 56Kbps)

        - NSF establishes 5 super-computing centers to provide high-computing

          power for all (JVNC@Princeton, PSC@Pittsburgh, SDSC@UCSD, NCSA@UIUC,

          Theory Center@Cornell).

        ARPANET bureaucracy keeps it from being used to interconnect

          centers and NSFNET comes into being with the aid of NASA and DOE.

        - This allows an explosion of connections, especially from



        Cleveland Freenet (start of NPTN) comes on-line


        Network News Transfer Protocol (NNTP) designed to enhance Usenet news

        performance over TCP/IP.


        Mail Exchanger (MX) records developed by Craig Partridge allowing

        non-IP network hosts to have domain addresses.


1987    NSF signs a cooperative agreement to manage the NSFNET backbone with

        Merit Network, Inc. (IBM and MCI involvement was through an agreement

        with Merit).  Merit, IBM, and MCI later founded ANS.


        UUNET is founded with Usenix funds to provide commercial UUCP and

        Usenet access.


        1000th RFC: "Request For Comments reference guide"


        # of hosts breaks 10,000


        # of BITNET hosts breaks 1,000


1988    Robert Morris’s Internet worm burrows through the Net breaking into and

        crashing SUN and VAX UNIX machines world wide.


1989    ARPANET formally expired - many rumors that Internet will die.


        # of hosts breaks 100,000


        NSFNET backbone upgraded to T1 (1.544Mbps)


        RIPE (Reseaux IP Europeens) formed (by European service providers) to

        ensure the necessary administrative and technical coordination to

        allow the operation of the pan-European IP Network


        First relay between a commercial electronic mail carrier (Compurserve)

        and the Internet through Ohio State University


        World-Wide Web network developed by Tim Berners-LEE at CERN in Europe.




        Second relay between a commercial electronic mail carrier (MCI Mail)

        and the Internet through the Corporation for the National Research

        Initiative (CNRI)


        EFF - Electronic Frontier Foundation is founded by Mitch Kapor


        Hytelnet released by Peter Scott (U of Saskatchewan)


1991    Commercial Internet eXchange (CIX) Association, Inc. formed by General

        Atomics (CERFnet), Performance Systems International, Inc. (PSInet),

        and UUNET Technologies, Inc. (AlterNet)


        WAIS released by Thinking Machines Corporation


        Gopher released by University of Minnesota


        US High Performance Computing Act (Gore 1) establishes the National

        Research and Education Network (NREN)


1992    Internet Society is chartered


        World-Wide Web (WWW) released by CERN


        # of hosts breaks 1,000,000


        NSFNET backbone upgraded to T3 (44.736Mbps)


        First MBONE audio multicast (March) and video multicast (November)


1993    InterNIC created by NSF to provide specific Internet services

          - directory and database services (AT&T)

          - registration services (Network Solutions Inc.)

          - information services (General Atomics/CERFnet)


        US White House comes on-line:

          - President Bill Clinton:

          - Vice-President Al Gore:


        Internet Talk Radio begins broadcasting


        United Nations and World Bank come on-line


        US National Information Infrastructure Act


        Mosaic takes the Internet by storm; WWW proliferates at a 341,634%

        annual growth rate of service traffic.  Gopher's growth is 997%.


1994    Communities begin to be wired up directly to the Internet


        US Senate and House provide information servers


        Mass marketing finds its way to the Internet with mass e-mailings


        Worms of a new kind find their way around the Net - WWW Worms (W4),

        joined by Spiders, Wanderers, Crawlers, and Snakes ...


Old hardware I made while at Stanford.


10 Channel Fiber Optic or Thermocouple Positioning system, to map 2D temperature distribution in a plane. 

128 channel High Speed  Type T Thermocouple board 

PC layout for multiplexer board. 

PC Computer Controlled Kiln

     Used a HPIB IEEE-488 temperature sensor and home made opto isolated triac setup.   For baking polyamide films on to 1mm Stainless Steel trocar needles.  

CyberJava - Outlook July 26, 1995 Newspaper clipping.


Outlook July 26, 1995 


Wednesday, March 16, 2022

Numbers that are products of distinct primorial numbers

I'm officially credited with a number sequence.

A129912Numbers that are products of distinct primorial numbers (see A002110).22
1, 2, 6, 12, 30, 60, 180, 210, 360, 420, 1260, 2310, 2520, 4620, 6300, 12600, 13860, 27720, 30030, 37800, 60060, 69300, 75600, 138600, 180180, 360360, 415800, 485100, 510510, 831600, 900900, 970200, 1021020, 1801800, 2910600, 3063060, 5405400 (listgraphrefslistenhistorytextinternal format)



Conjecture: every odd prime p is either adjacent to a term of A129912 or a prime distance q from some term of A129912, where q < p. - Bill McEachen, Jun 03 2010, edited for clarity in Feb 26 2019

The first 2^20 terms k > 2 of A283477 all satisfy also the condition that the differences k-A151799(k) and A151800(k)-k are always either 1 or prime, like is also conjectured to hold for A002182 (cf. also the conjecture given in A117825). However, for A025487, which is a supersequence of both sequences, this is not always true: 512 is a member of A025487, but A151800(512) = 521, with 521 - 512 = 9, which is a composite number. - Antti Karttunen, Feb 26 2019


CRC Standard Mathematical Tables, 28th Ed., CRC Press


T. D. Noe and Giovanni Resta, Table of n, a(n) for n = 1..10000 (first 1000 terms from T. D. Noe)

Bill McEachen, Normalized A129912

Robert Potter, Primorial Conjecture.

J. Sokol, Sokol's Prime Conjecture

Wikipedia, Primorial

Index entries for sequences related to primorial numbers