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Dolmen and burial mounds
Conny and I went walking in the forest near
Mander where there used to be a dolmen and where there are several burial
mounds. We also went searching for border poles
and found the following:
We again searched for pole 86-IV, but did not
find it. We concluded that it must have been removed.
- At 13:55, pole 86.
- At 14:08, pole 85-I.
- At 14:12, pole 85-II.
- At 14:39, pole 86-I
Today, we went home from our stay in
Manderveen. We decided to search for two border
poles, but while drivingvthrough Germany, Conny thought that she saw some one. At first I dismissed it, thinking we
were too far from the border, but than we saw another one. We went back to
have a look at them. We visited the followein border poles:
- At 9:30, pole 92-I.
- At 9:48, pole 88-I.
- At 10:22, pole 60.
- At 10:26, pole 62, 62-I, and 62-II.
- At 10:40, pole 61.
Some wet snow
This afternoon, we had some wet snow. It is the first
wet snow of this winter. Because temperatures are above zero Celsius, there is
no chance the snow will stay on the ground.
This afternoon, Conny and I mada a walk
through the country side. At one point, while walking with the sun on our
backs, we noted some bright spots in the clouds. We noted some other bright
spots in some other clouds, and realized that they were on a bow. When we
walked further the bow became clearer. We also noticed some slight colouration:
red on the outside and blue on the inside. We took several pictures. Above one
that I stiched together (with Hugin) from two pictures. At home, I concluded that the phenomenon we
saw was like a fog bow, or
also called a white rainbow. Because it was not
in the fog, but in a cloud, I would call it a cloud bow.
Today is palindome date of the form (D)D-(M)M-YY
and/or YY.(M)M.(D)D: 12-1-21 and/or 21.1.12. This year there are nine
other palindrome date like this and six other special dates, one of which
we already have had. All of these, including today, are:
There are also a lot of palindrome dates of the format M(M)/D(D)/YY in January and December (besides some already mentioned
- January 2: Palindrome date M/D/YY and YY.M.D, double date: M-D-YY.
- January 12: Palindrome date DD-M-YY and YY.M.DD.
- February 1: Palindrome date D-M-YY, double date M/D/YY and YY.M.D
- February 10: Double date MM/DD/YY and YY.MM.DD.
- February 12: Palindrome date DD-MM-YYYY, DD-M-YY and YY.M.DD.
- March 12: Palindrome date DD-M-YY and YY.M.DD.
- April 12: Palindrome date DD-M-YY and YY.M.DD.
- May 12: Palindrome date DD-M-YY and YY.M.DD.
- June 12: Palindrome date DD-M-YY and YY.M.DD.
- July 12: Palindrome date DD-M-YY and YY.M.DD.
- August 12: Palindrome date DD-M-YY and YY.M.DD.
- September 12: Palindrome date DD-M-YY and YY.M.DD.
- November 12: Palindrome date DD-MM-YY and YY.MM.DD.
- December 2: Palindrome date MM/DD/YYYY and YYYY.MM.DD.
- December 11: Palindrome date MM/DD/YY, double date MM/DD/YY and YY.MM.DD.
- December 22: Palindrome date MM/DD/YY, double date MM/DD/YY and YY.MM.DD.
- January 21 - 29, 2021: 1/21/21 - 1/29/21
- December 1 - 9, 2021: 12/1/21 - 12/9/21
Literate programming with Markdown
On March 20, I am going to give a (online) workshop on parsing. The workshop
will start of with a overview of parsing and than explain the decision I took
for implementing IParse. In
the second part of the workshop, will consist of writing some simple grammar
for IParse and test it on input. I am thinking about discussing RawParser, a reimplementation of IParse in 'raw' C, in the last part of
the workshop. In the past months I have been working on RawParser and trying to
add extensive documents to explain how it works, but I do not feel very happy
about all the restrictions that C imposes on the order and level of detail
you have to provide. A few days ago, I came across Build Your Own Text Editor and was rather charmed by it approach. It is
generated from a collection of Markdown files and a steps.diff file with the help of a program
called leg. This made me
think about using Markdown as the primary source of the code and write a
program to generate a C program from a collection of Markdown files as a form
programmin. I think it is possible to make the program smart enough to
reorder the Markdown code fragments and to allow a mechanism for extending the
code without having to include many instructions where to include which piece
of the code as in CWEB, a
computer programming system created by Donald Knuth and Silvio Levy as a
follow-up to Knuth's WEB literate programming system. I have started this
approach on RawParser/docs/grammar.md file. As a positive side effect,
working on this did result into some improvement of
Yesterday, on the news there was an issue about how today a snow front would go over the country from the west to the east. Yesterday
morning, I already saw some small snow specks fall from the sky, some of which
stayed on the roofs of the houses. In the evening, I made some curly kail hotchpotch (with no fried pork but with smoked sausage). Only
in the evening, it started to snow and some of it on the roads. At least about
2.5cm of snow fell during the evening, based on my own measurement. The coming
days the temperature is going to rise and the snow is expected to quickly melt
The authorities reported that the spread of the VUI - 202012/01 COVID-19 variant in
the Netherlands is no longer contained. They estimate that now about 10% of the
COVID cases are the VUI - 202012/01 variant. I am not surprised about this. The
authorities have over and over failed in this respect. They are expecting that
by April it will be the dominant variant leading to next wave and advising the
government to take new measures. The government is thinking about a curfew from
20:00 till 4:00. The experts of the RIVM should have realized that the new variants with higher infection
rates were to arise and plan ahead to counter this. As far as I know, they did
not do anything. They even did not enough screening of variants to detect the
development of mutations. And once the new variant was discovered, they failed
to scale up testing to contain this variant. It seems that they only thing
they did was to estimate the spread of the new variant in order that they
could adise the government with respect to measures to be taken. That can be
seen as a clever strategy to avoid their primary responsibility to contain the
spread of infectious diseases. Over and over again our government has failed
to contain the spread of the virus by means of testing and contact research. It
is only since a few months that people who do not have symptoms can be tested.
Software engineering is mostly a craft
In my experience as a software engineer for many years, I feel that software engineering is still heavily relying on craftmanship to such an
extend that it barely can be called engineering. With engineering, I understand
a well defined process to arrive at a reliable solution for a well specified
problem by applying a standard set of methods. Of course, software engineering
is operating in a context where the problem specification is volutile and
usually not well understood from the start of a project. But that can also be
seen as a motivation for a more enginering based approach to quickly respond to
changing requirements. Currently, most software development is done by writing
code, which contains the specified problem and its implementation mixed in
such away that it is often not possible to see which is which. So far, not many
tools have been developed for a more engineering approach to software
engineering. Almost every day new programming languages are proposed, but most
of these are just new combinations of language construct in other languages
and/or an alternative way to implement them. Most of these languages end a
silent death. Most of the software engineering of today is related to data
management, where multiple people operate on a shared data repository, either
through websites or dedicated applications. Although there are some
development platforms they usually work with simple data models. There are
some low-code development platforms that are more promesing. (One that I know
of is the one developed by ThinkWise.) I believe that these platforms can only succesfull if they are
based on rich semantic models. These kind of no/low-code platforms implement
just one implementation strategy from a high-level specification to an
executable platform. What I am thinking of is the development of languages that
specify how a high-level specification can be implemented using lov-level
programming languages. I understand that this is a very hard problem. I have
started developing a data specification language, which I called DataLang, a
name that also has been used for similar approaces. An introduction to this
can be found here.
In the document COVID-19, 25e Tweede Kamer briefing, 20 jan 2021 (in Dutch),
yesterdays technical briefing of the RIVM to House of Representatives of the Netherlands, it mentions (on page 28)
some statistics with respect to nonpharamceutical interventions against
COVID-19. On the page there references to
scientific publications: The effectiveness of eight nonpharmaceutical interventions against COVID-19
in 41 countries, Ranking the effectiveness of worldwide COVID-19 government interventions,
Early assessment of the impact of mitigation measures to control COVID-19 in
22 French metropolitan areas, October to November 2020, and
Early Assessment of Curfew and Second COVID-19 Lock-down on Virus Propagation
in France. I presume that the graph presented on the page is based on the
data from these (and possible other) publications. It clearly shows that
mandating to wear masks in (some) public spaces is not very effective. And
also that the effectivess of stay-at-home order (with exemptions) on the
reproduction number is about 20%. At the moment there is no strong support for
a curfew in the House of Representatives of the Netherlands, because there are
doubts about the effectiveness with respect to impact of the measure, which in
the Netherlands with a strong culture of personal freedom and choice, is seen
as a last resort type of measure.
Conny gave me book Trajecten door Utrecht
7 written by D.T. Koen and J. Renes in Dutch and published by
Het Utrechts Archief in
2003, ISBN:9076366128. With the book there is a
reproduction of a map of the province of Utrecht from 1743 (second edition).
Conny and I travelled along the Schoonebeker
Diep at the border of Germany, which is actually the part of the Grenzaa river, which starts in Germany, that is on the border. We
followed it in search of border poles. Because
the border is in the middle of the river, border poles were placed in pairs at
both sides of the river, where the exact middle of the two poles signifies the
position of the border. In some cases, only the pole on the Dutch side is left.
We followed the book Op zoek naar grenspalen and maps from
Topografische atlas van Drenthe proved very
helpful. There is a biking path along a large part of the river. We traveled
by car and could not follow the river over the whole distance but had to use
the road from Coevorden to Nieuw-Schoonebeek. We failed to locate the border
pole 152-I. We made a short walk through the center of Nieuw-Schoonebeek. We
found the following border poles (and two shields on a bridge).
- At 13:27, pole 151-V (N), which had fell sideways.
- At 13:31, pole 151-V (D).
- At 14:07, pole 151-VI, which had fell sideways.
- At 14:30, pole 152 (N). We saw pole 152 (D)
from a distance on the other side of the river.
- At 14:55, shield 152-II on the bridge.
- At 14:57, shield 152-III on the bridge.
- At 14:59, pole 153 (D).
- At 15:02, pole 153 (N), which had fell backwards.
- At 15:18, pole 153-I (N).
- At 15:19, pole 153-I (D).
- At 15:25, pole 154 (N).
- At 15:27, pole 154 (D).
- At 15:59, pole 155 (N).
- At 16:03, pole 155 (D).
Afterwards, we traveled to the Germany village Neugnadenfeld where we visited
two graveyards. During the second world war it was the location of a prisoner
of war camp with primarily Russian soldiers. Because Russia had not signed the
Convention, the Russian solders were not protected by it. As a result of
this, many died and were thrown in a mass grave. After the war, members of
the Moravian Church
from Germany and other parts of (Eastern) Europe were granted the establish a
village at the location of the camp. At their graveyard people are buried in
order of their date of death and the graves have simple and similar looking
tombstone. There is a rahter strong constrast between the two graveyards.
At 13:42:16, I bought the following books from the Taschen:
These are not the type of books that I would normally buy, but because I have
bookshops (as non-essential shops) have been closed since December 15, I could not resist the urge to buy
- Oliver Byrne. Six Books of Euclid written by
Byrne and Werner Oechslin, written in English, French, and German,
published by Taschen Gmbh in December 2020,
ISBN:9783836559386, for € 15.
- Contemporary Houses. 100 Homes Around the World written by Philip
Jodidio in English, French, and German, published by Taschen Gmbh in 2020,
ISBN:9783836583954, for € 35.
Online interactive parser
interactive parser for educational purposes, which I am going to use this
for workshop that I will be giving for TkkrLab on Saturday, March 20.
This months interesting links
| December 2020
| February 2020