<?xml version="1.0" encoding="UTF-8"?><?xml-stylesheet type="text/xsl" href="static/style.xsl"?><OAI-PMH xmlns="http://www.openarchives.org/OAI/2.0/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/ http://www.openarchives.org/OAI/2.0/OAI-PMH.xsd"><responseDate>2026-09-18T19:41:49Z</responseDate><request verb="GetRecord" identifier="oai:www.repository.cam.ac.uk:1810/245023" metadataPrefix="uketd_dc">https://api.repository.cam.ac.uk/server/oai/request</request><GetRecord><record><header><identifier>oai:www.repository.cam.ac.uk:1810/245023</identifier><datestamp>2024-06-26T13:50:20Z</datestamp><setSpec>com_1810_195217</setSpec><setSpec>com_1810_256065</setSpec><setSpec>col_1810_219484</setSpec></header><metadata><uketd_dc:uketddc xmlns:uketd_dc="http://naca.central.cranfield.ac.uk/ethos-oai/2.0/" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:dcterms="http://purl.org/dc/terms/" xmlns:uketdterms="http://naca.central.cranfield.ac.uk/ethos-oai/terms/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:doc="http://www.lyncode.com/xoai" xsi:schemaLocation="http://naca.central.cranfield.ac.uk/ethos-oai/2.0/ http://naca.central.cranfield.ac.uk/ethos-oai/2.0/uketd_dc.xsd">
   <dc:title>Application of mixed-integer programming in chemical engineering</dc:title>
   <dc:identifier xsi:type="dcterms:DOI">10.17863/CAM.16074</dc:identifier>
   <dc:creator>Pogiatzis, Thomas</dc:creator>
   <dcterms:abstract>Mixed-Integer Programming has been a vital tool for the chemical engineer&#xd;
in the recent decades and is employed extensively in process design and control.&#xd;
This dissertation presents some new Mixed-Integer Programming formulations&#xd;
developed for two well-studied problems, one with a central role in the area of&#xd;
Optimisation, the other of great interest to the chemical industry. These are the&#xd;
Travelling Salesman Problem and the problem of scheduling cleaning actions for&#xd;
heat exchanger networks subject to fouling.&#xd;
The Travelling Salesman Problem  finds a plethora of applications in many&#xd;
scientific disciplines, Chemical Engineering included. None of the mathematical&#xd;
programming formulations proposed for solving the problem considers fewer than&#xd;
O(n^2) binary degrees of freedom. The first part of this dissertation introduces a&#xd;
novel mathematical description of the Travelling Salesman Problem that succeeds&#xd;
in reducing the binary degrees of freedom to O(nlog2(n)). Three Mixed-Integer&#xd;
Linear Programming formulations are developed and the computational performance&#xd;
of these is tested through computational studies.&#xd;
Sophisticated methods are now available for scheduling the cleaning actions&#xd;
for networks of heat exchangers subject to fouling. In the majority of these, only&#xd;
one form of cleaning is used, which restores the performance of the exchanger&#xd;
back to its clean level. A recent study revised the scheduling&#xd;
problem for the case where there are several cleaning methods available. The&#xd;
second part of this dissertation extends their approach, developed for individual&#xd;
units, to heat exchanger networks and explores the concept of selection of cleaning&#xd;
techniques further. Mixed-Integer Programming formulations are proposed for&#xd;
the scheduling task, for two fouling scenarios: (i) chemical reaction fouling and&#xd;
(ii) biological fouling. A series of results are presented for the implementation of&#xd;
the scheduling formulations to networks of different sizes.</dcterms:abstract>
   <uketdterms:institution>University of Cambridge</uketdterms:institution>
   <dcterms:issued>2013-06-11</dcterms:issued>
   <dc:type>Thesis</dc:type>
   <uketdterms:qualificationlevel>Doctoral</uketdterms:qualificationlevel>
   <uketdterms:qualificationname>Doctor of Philosophy (PhD)</uketdterms:qualificationname>
   <dc:language>en</dc:language>
   <dcterms:isReferencedBy xsi:type="dcterms:URI">https://www.repository.cam.ac.uk/handle/1810/245023</dcterms:isReferencedBy>
   <dc:identifier xsi:type="dcterms:URI">https://apollo8-f-pro.lib.cam.ac.uk/bitstreams/88e28d2a-0e82-4028-b36e-97b0163ec0c9/download</dc:identifier>
   <uketdterms:checksum xsi:type="uketdterms:MD5">8a9fe485bbcb76b9c51f456e55e39153</uketdterms:checksum>
   <dcterms:license>https://apollo8-f-pro.lib.cam.ac.uk/bitstreams/73f999af-ba2b-4251-9813-34c4517341f1/download</dcterms:license>
   <uketdterms:checksum xsi:type="uketdterms:MD5">835269bda140c10400fe0606a14c3d21</uketdterms:checksum>
   <dc:rights>https://www.rioxx.net/licenses/all-rights-reserved/</dc:rights>
   <dc:subject>Chemical engineering</dc:subject>
   <dc:subject>Mixed-integer programming</dc:subject>
   <dc:subject>Travelling salesman problem</dc:subject>
   <dc:subject>Heat exchanger</dc:subject>
   <dc:subject>Optimisation</dc:subject>
   <dc:subject>Scheduling</dc:subject>
</uketd_dc:uketddc>
</metadata></record></GetRecord></OAI-PMH>