PlaatSoft

PlaatSoft has released a new version of the BassieMusic Android App in the Google Play Store.

The following changes were made:
– Various changes to modernize the codebase
– Update the icon to have some more shadow
– Add themed monochrome icon
– Move some buttons around in the app bar
– Build for Android 16

Click here to download the latest version.

PREFIX ex:
PREFIX geo:
PREFIX owl:
PREFIX rdf:
PREFIX rdfs:
PREFIX xsd:

ex:Army rdf:type owl:Class;
rdfs:comment “A class representing army.”@en;
rdfs:label “Army” .

ex:hasArmy rdf:type owl:ObjectProperty;
rdfs:comment “The player has army.”@en , “The city has army.”@en;
rdfs:domain ex:Player , ex:City;
rdfs:label “has army”;
rdfs:range ex:Army .

ex:City rdf:type owl:Class;
rdfs:comment “A class representing city.”@en;
rdfs:label “City” .

ex:hasPlayer rdf:type owl:ObjectProperty;
rdfs:comment “The army has player.”@en;
rdfs:domain ex:Army;
rdfs:label “has player”;
rdfs:range ex:Player .

ex:hasCity rdf:type owl:ObjectProperty;
rdfs:comment “The army has city.”@en;
rdfs:domain ex:Army;
rdfs:label “has city”;
rdfs:range ex:City .

geo:hasGeom rdf:type owl:DatatypeProperty;
rdfs:comment “The city has geom.”@en;
rdfs:domain ex:City;
rdfs:label “has geom”;
rdfs:range geo:wktLiteral .

ex:hasConnection rdf:type owl:ObjectProperty;
rdfs:comment “The city has connection.”@en;
rdfs:domain ex:City;
rdfs:label “has connection”;
rdfs:range ex:City .

geo:hasCrs rdf:type owl:DatatypeProperty;
rdfs:comment “The city has crs.”@en;
rdfs:domain ex:City;
rdfs:label “has crs”;
rdfs:range .

ex:hasName rdf:type owl:DatatypeProperty;
rdfs:comment “The army has name.”@en , “The player has name.”@en , “The city has name.”@en;
rdfs:domain ex:Army , ex:Player , ex:City;
rdfs:label “has name”;
rdfs:range xsd:string .

ex:hasProduction rdf:type owl:DatatypeProperty;
rdfs:comment “The city has production.”@en;
rdfs:domain ex:City;
rdfs:label “has production”;
rdfs:range xsd:integer .

ex:hasSize rdf:type owl:DatatypeProperty;
rdfs:comment “The army has size.”@en;
rdfs:domain ex:Army;
rdfs:label “has size”;
rdfs:range xsd:integer .

ex:Player rdf:type owl:Class;
rdfs:comment “A class representing player.”@en;
rdfs:label “Player” .

ex:hasEmail rdf:type owl:DatatypeProperty;
rdfs:comment “The player has email.”@en;
rdfs:domain ex:Player;
rdfs:label “has email”;
rdfs:range xsd:string .

# On windows start a console in Administrator mode
cmd

# Go to the JVM directory (For example)
cd C:\Program Files\Java\jdk1.8.0_351\jre\lib\security

# Add cert.crt to JVM
keytool -importcert -file cert.crt -keystore cacerts -storepass changeit -noprompt -alias alias

This evening i deployed a new Raspberry Pi with the following software:
– Debian 6.12.17-v8+ (64Bits)
– HaProxy 2.6.12
– Letsencrypt (Latest version)

This new Reverse Proxy node is replacing a very old Raspberry Pi which was running for more then 9 years.

JSON API’s
/api/1/vitals
/api/1/wifi_status
/api/1/lifetime
/api/1/version
/tedapi/v1

HTTP API
/service

See also here

RDF Graph example (Query language: SPARQL)

As a framework for representing the Web, Resource Description Framework (RDF) captures structure using a triple, the basic unit in RDF. A triple is a statement with three elements: two nodes connected by an edge (also known as a relationship). Each triple is identified by a Uniform Resource Identifier (URI) as subject-predicate-object:

– The subject is a resource (node) in the graph;
– The predicate represents an edge (relationship)
– The object is another node or a literal value.

More information:
https://rdf4j.org/documentation/tutorials/getting-started/

Property Graph example (Query Language: Cypher)

Information is organized as nodes, relationships, and properties in a property graph. Nodes are tagged with one or more labels, identifying their role in the network. Nodes can also store any number of properties as key-value pairs. Relationships provide directed, named connections between two nodes. Relationships always have a direction, a type, a start node, and an end node, and they can have properties, just like nodes. Although relationships are always directed, they can be navigated efficiently in either direction.

What is the difference between SPARQL and Cypher Query Language?
– SPARQL is the query language for accessing data in the Resource  description Framework (RDF) GRAPH database.
– Cypher is the corresponding language for the data represented in property GRAPH database

More information:
https://neo4j.com/blog/rdf-vs-property-graphs-knowledge-graphs/

INSERT
CREATE (diana:Person {name: “Diana”})
CREATE (melissa:Person {name: “Melissa”, twitter: “@melissa”})
CREATE (xyz:Company {name: “XYZ”})
CREATE (diana)-[:WORKS_FOR]->(xyz)
CREATE (diana)-[:IS_FRIENDS_WITH]->(melissa)

UPDATE
MATCH (p:Person {name: ‘Diana’}) SET p.birthdate = date(‘1980-01-01’)
MATCH (:Person {name: ‘Diana’})-[rel:WORKS_FOR]-(:Company {name: ‘XYZ’}) SET rel.startYear = date({year: 2018})

DELETE
MATCH (j:Person {name: ‘Diana’})-[r:IS_FRIENDS_WITH]->(m:Person{name: ‘Melissa’}) DELETE j,r,m

SELECT
MATCH (p:Product) RETURN p.productName, p.unitPrice ORDER BY p.unitPrice DESC LIMIT 10;

INSERT

PREFIX plaat: <http://www.plaatsoft.nl/>
INSERT DATA {
<http://leerling/1> plaat:firstName “Kees”.
<http://leerling/2> plaat:firstName “Jan”.
<http://leerling/3> plaat:firstName “Piet”.
<http://leerling/4> plaat:firstName “Klaas”.
<http://school/1> plaat:name “Bospark”.
<http://school/1> plaat:level “LTS”.
<http://school/1> plaat:city “Alphen aan den Rijn”.
<http://school/2> plaat:name “Lammerschans”.
<http://school/2> plaat:level “MTS”.
<http://school/2> plaat:city “Leiden”.
<http://school/3> plaat:name “Hogeschool van Utrecht”.
<http://school/3> plaat:level “HTS”.
<http://school/3> plaat:city “Utrecht”.
<http://leerling/1> plaat:school <http://school/1>.
<http://leerling/1> plaat:school <http://school/2>.
<http://leerling/1> plaat:school <http://school/3>.
<http://leerling/2> plaat:school <http://school/1>.
<http://leerling/3> plaat:school <http://school/2>.
}

QUERY
# Show all leerlingen of school1
PREFIX plaat: <http://www.plaatsoft.nl/>
SELECT ?x ?firstName
WHERE
{
?x plaat:firstName ?firstName.
?x plaat:school <http://school/1>
}

DELETE
PREFIX plaat: <http://www.plaatsoft.nl/>
DELETE { ?x plaat:firstName ‘Kees’ }
WHERE { ?x plaat:firstName ‘Kees’ }

UPDATE (SPARQL use delete / insert pattern)
PREFIX plaat: <http://www.plaatsoft.nl/>
DELETE { ?x plaat:firstName ‘Kees’ }
INSERT { ?x plaat:firstName ‘William’ }
WHERE { ?x plaat:firstName ‘Kees’ }

Today i have migrated most of my websites to new hardware:
– Raspberry Pi 4B (2GB) / 32GB SDCard.

I have also upgrade the following software:
– Operating System to Debian Bookworm (kernel 6.1.0-rpi7-rpi-v8)
– WordPress to v6.4.2
– php to v8.2.7

If you detect any problem, please let me known!