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Object Based GIS-T Data Model for Road Infrastucture Maintenance in Uganda
No full textAbstract
There are several cases of poor transport services in Uganda that are caused by
the bad state of roads. Road maintenance proved ad hoc until recently when the
need for preventive maintenance was recognised and plans of making it a
priority put in place. Since roads are geographically located, the use of
Geographical Information Technologies (GITs) in collecting, managing and
analysing road condition is paramount. And yet, these technologies are under
utilized for road maintenance. This paper derives from research aimed at
accentuating the use of GITs for Road Infrastructure Maintenance (RIM) in
Uganda. The research addressed three objectives, (1) to access the gaps and
limitations in GIT use and access for RIM, (2) to develop a methodological
framework for enhancing the use of GITs in RIM and (3) to develop a
Geographical Information Systems for Transportation (GIS-T) data model for RIM
in Uganda. In line with the 3rd objective, the paper specifically presents an
object data model for RIM. This was accomplished through identification of road
maintenance data requirements, review of: organisational reports, workshop
proceedings, organisational terms of reference for various projects and
existing data models & standards in transportation. An understanding and
consideration of the Information Quality Levels (IQL) was paramount. This
resulted into a conceptual and logical data model for RIM based on concepts of
dynamic segmentation and linear referencing. The conceptual model depicted
using entity relationship diagrams identifies with 3 entities - the road’s
network and the point and line events that exist on it. Besides logically
documenting the various classes from the conceptual data model, the ESRI
provided template for logical data modelling was used. The model separately
emphasizes objects having spatial reference, objects without spatial reference
and the relationships between them. The study concludes that a common
definition and understanding of the country’s transportation network is
essential to adoption of the proposed model. The choice of GIS software with
the full set of dynamic segmentation tools is fundamental for implementation of
the physical model. This idea of modelling data is a contribution to
standardisation of geographic data sets for the sector.
Keywords
Data model; Dynamic segmentation; Geographical Information Technologies (GITs);
Road Infrastructure Maintenance (RIM); Linear referencing; Ugand
Öppen data - en ny utmaning för forskningsbiblioteken
No full textI snart 20 år har svenska bibliotekarier arbetet för att realisera open access
inom vetenskaplig publicering. Men det är först det senaste året man talar om
att en vändpunkt nåtts; att över 50 procent av publikationerna finns öppet
tillgängliga. Nu hoppas vi på nerförsbacke och kanske en del frihjul framöver
men så dyker en ny krök i vägen upp som pockar på uppmärksamhet – öppen data.
Plötsligt duger inte kompetensen och verktygslådan längre
A sensitivity analysis of total cost of ownership for electric public bus transport systems in Swedish medium sized cities
No full textTo reach Swedish national climate change reduction targets, organizations
collaborate for a sustainable development to improve energy efficiency,
reducing pollution and noise in public bus transport. This follow-up study
continues to strengthen the previous study by deepen the economic comparisons
of two electric buses with different driving range and different type of
chargers. The study aims to emphasize on sensitivity analysis for the total
cost of ownership (TCO) to reduce uncertainty by identifying which factors of
interest that most likely cause the estimated cost values for the electric bus.
The result shows that the percentage change of line distance (km/year),
operational years, and investment cost would be the most influential and
significant factors on TCO
Lärarlärdom Högskolepedagogisk konferens 2014
No full textHögskolepedagogisk utveckling har under senare år fått en tydligare och mer
framträdande roll vid universitet och högskolor. Under senare år har också ett
allt större fokus riktats mot utbildningars resultat. Frågor som rör kvaliteten
i undervisningen blir därmed centrala. Att utveckla och stödja lärares
pedagogiska skicklighet samt belysa villkoren för den undervisning som bedrivs
inom högre utbildning är angeläget. Behovet av en gemensam samlingspunkt för
pedagogiska och didaktiska diskussioner där BTH:s och Högskolan i Kristianstads
lärare kan träffas och föra dessa diskussioner tillsammans och över
ämnesgränser är stort. Genom att anordna en årlig högskolepedagogisk konferens
vill vi främja ett utbyte av erfarenheter från den dagliga undervisningen och
insikter kring det lärande som möjliggörs.
Lärarlärdom 2014 gick av stapeln på Blekinge Tekniska Högskola den 20 augusti
och samlade ett femtiotal deltagare.
Den inledande föreläsningen samt ytterligare fem presentationer finns inspelade
och nås via:
http://distans.hkr.se/wid/ChristinaHansson/lararlardom_bth2014
Video Conference as a Tool to Enable Participation in Discharge Planning – Experiences From Implementers about the Implementation Process
No full textThe problems and challenges that arise in the task of improving discharge
planning have been an area of concern for many years, including problems
related to the lack of time for professionals to participate. In a county
council area in South East Sweden, video conferencing was implemented in
discharge planning sessions to enable distance participation. As part of a
larger research study of the implementation process, interviews were conducted
with two of the implementers. The interviews were analysed qualitatively, using
directed content analysis with a deductive approach to considering a framework
developed by Nilsen et al. The results of this study are consistent with the
actual framework but with the addition of time, i.e. time to prepare, time to
understand, time to run through and time to reflect. Further research is
proposed to focus more on leadership during the implementation process and its
influence on the meaning of time
Handleda handledarna
No full textBakgrund och genomförande
Uppsatshandledning är en väsentlig förutsättning för och del av studenternas
kandidat- eller magisterexamen. På sjuksköterskeprogrammet (180 hp) ges dels en
yrkesexamen (sjuksköterskeexamen) samt en kandidatexamen.
Examensarbetet/uppsatskursen på sjuksköterskeprogrammet på BTH omfattar 15 hp
och involverar lärare och doktorander med minst en magisterexamen att handleda
studenterna. Någon formell utbildning i att handleda uppsatser har dock varken
krävts eller tidigare tillhandahållits på institutionen.
För att öka handledarnas kompetens anordnades 2012-2013 en kurs i
”uppsatshandledning för högskolelärare” (4 hp) på institutionen. Kursen gavs på
arbetstid och var upplagd med fyra studieträffar med en månads mellanrum.
Förutom studieträffar och diskussionsgrupper innehöll kursen tre skriftliga
inlämningsuppgifter samt en avslutande skriftligt examinationsuppgift som var
obligatoriska för de som ville få ut 4 hp på kursen. Det var även möjligt att
följa kursen utan att ta ut några poäng. Det var 30 lärare och doktorander som
följde kursen, varav 27 lämnade in inlämningsuppgifter och 19 fullföljde hela
kursen.
En skriftlig och anonym utvärderingsenkät avslutade kursen. Enkäten visade att
19 av de 25 som besvarade enkäten gav kursen betyget bra eller mycket bra som
sammanfattande omdöme, 5 gav kursen betyget godkänt medan 1 svarade att kursen
varit dålig. Överlag fick kursen och kursens upplägg bra betyg och endast
själva examinationsuppgiften ansågs mindre bra.
Utöver kursen anordnas nu regelbundet vid institutionen tre gånger varje termin
”handledning på handledning” som ett diskussionsforum där examinatorer och
handledare träffas och kan diskutera allmänna och generella problem i uppsatser
och uppsatshandledning.
Diskussion
En formell kurs i uppsatshandledning kan vara ett sätt att stärka handledarna
och handledarrollen i uppsatshandledning. Erfarenheterna från den kurs som
getts vid Institutionen för hälsa på BTH visar att kursen uppskattats av såväl
erfarna handledare som nybörjare. Utvärderingen visade att upplägget av och
omfattningen på kursen var ”lagom”, medan själva examinationsuppgiften kan
utvecklas och göras tydligare. Utbildning är viktig för att få en gemensam
plattform, inte bara för en likriktning, men även som en gemensam grund när
diskussionsforumet bedrivs. Dock är en kurs en punktinsats, även om den
upprepas. Diskussionsforumet behöver finnas för att upprätthålla kontinuitet i
den löpande handledningen. De regelbundet återkommande träffarna mellan
handledare och examinatorer utgör en bra grund för gemensamma diskussioner om
studenternas uppsatser och gör det dels möjligt att höja kvaliteten på
examensarbetena och dels för att undvika missförstånd mellan handledare och
examinatorer
On Fundamental Elements of Visual Navigation Systems
No full textVisual navigation is a ubiquitous yet complex task which is performed by many
species for the purpose of survival. Although visual navigation is actively
being studied within the robotics community, the determination of elemental
constituents of a robust visual navigation system remains a challenge. Motion
estimation is mistakenly considered as the sole ingredient to make a robust
autonomous visual navigation system and therefore efforts are made to improve
the accuracy of motion estimations. On the contrary, there are other factors
which are as important as motion and whose absence could result in inability to
perform seamless visual navigation such as the one exhibited by humans.
Therefore, it is needed that a general model for a visual navigation system be
devised which would describe it in terms of a set of elemental units. In this
regard, a set of visual navigation elements (i.e. spatial memory, motion
memory, scene geometry, context and scene semantics) are suggested as building
blocks of a visual navigation system in this thesis. A set of methods are
proposed which investigate the existence and role of visual navigation elements
in a visual navigation system. A quantitative research methodology in the form
of a series of systematic experiments is conducted on these methods. The thesis
formulates, implements and analyzes the proposed methods in the context of
visual navigation elements which are arranged into three major groupings; a)
Spatial memory b) Motion Memory c) Manhattan, context and scene semantics. The
investigations are carried out on multiple image datasets obtained by robot
mounted cameras (2D/3D) moving in different environments.
Spatial memory is investigated by evaluation of proposed place recognition
methods. The recognized places and inter-place associations are then used to
represent a visited set of places in the form of a topological map. Such a
representation of places and their spatial associations models the concept of
spatial memory. It resembles the humans’ ability of place representation and
mapping for large environments (e.g. cities). Motion memory in a visual
navigation system is analyzed by a thorough investigation of various motion
estimation methods. This leads to proposals of direct motion estimation methods
which compute accurate motion estimates by basing the estimation process on
dominant surfaces. In everyday world, planar surfaces, especially the ground
planes, are ubiquitous. Therefore, motion models are built upon this
constraint. Manhattan structure provides geometrical cues which are helpful in
solving navigation problems. There are some unique geometric primitives (e.g.
planes) which make up an indoor environment. Therefore, a plane detection
method is proposed as a result of investigations performed on scene structure.
The method uses supervised learning to successfully classify the segmented
clusters in 3D point-cloud datasets. In addition to geometry, the context of a
scene also plays an important role in robustness of a visual navigation system.
The context in which navigation is being performed imposes a set of constraints
on objects and sections of the scene. The enforcement of such constraints
enables the observer to robustly segment the scene and to classify various
objects in the scene. A contextually aware scene segmentation method is
proposed which classifies the image of a scene into a set of geometric classes.
The geometric classes are sufficient for most of the navigation tasks. However,
in order to facilitate the cognitive visual decision making process, the scene
ought to be semantically segmented. The semantic of indoor scenes as well as
semantic of the outdoor scenes are dealt with separately and separate methods
are proposed for visual mapping of environments belonging to each type. An
indoor scene consists of a corridor structure which is modeled as a cubic space
in order to build a map of the environment. A “flash-n-extend” strategy is
proposed which is responsible for controlling the map update frequency. The
semantics of the outdoor scenes is also investigated and a scene classification
method is proposed. The method employs a Markov Random Field (MRF) based
classification framework which generates a set of semantic maps
Low-complexity codebook-based beamforming with four transmit antennas and quantized feedback channel
No full textIn this paper we propose a low-complexity codebook-based beamforming with four
transmit antennas and quantized feedback channel. The codebook design
aggregates the effect of power allocation and phase rotation through a simple
quantized transmit scheme. The codebook-based beamforming uses the feedback
information in order to maximize the instantaneous signal-to-noise ratio (SNR)
at the receiver. As a result, the proposed scheme presents an array gain. An
SNR analysis is performed and it is used to find the optimal feedback
information in the sense of maximizing the instantaneous SNR. A bit error rate
(BER) analysis for a quantized feedback channel is also derived and it is used
to compare to the results obtained for the proposed scheme under different
levels of quantization. Simulations are performed over quasi-static flat
Rayleigh fading channels for different closed-loop codebook-based schemes with
four transmit antennas and unitary transmission rate. Results illustrate that
the proposed scheme achieves full diversity order and outperforms other good
schemes in terms of array gain
Generating Structured Test Data with Specific Properties using Nested Monte-Carlo Search
No full textSoftware acting on complex data structures can be challenging to test: it is
difficult to generate diverse test data that satisfies structural constraints
while simultaneously exhibiting properties, such as a particular size, that the
test engineer believes will be effective in detecting faults. In our previous
work we introduced GödelTest, a framework for generating such data structures
using non-deterministic programs, and combined it with Differential Evolution
to optimize the generation process.
Monte-Carlo Tree Search (MCTS) is a search technique that has shown great
success in playing games that can be represented as sequence of decisions. In
this paper we apply Nested Monte-Carlo Search, a single-player variant of MCTS,
to the sequence of decisions made by the generating programs used by GödelTest,
and show that this combination can efficiently generate random data structures
which exhibit the specific properties that the test engineer requires. We
compare the results to Boltzmann sampling, an analytical approach to generating
random combinatorial data structures
Upright Stiff: subproblem updating in the FW method for traffic assignment
No full textWe present improvements of the Frank–Wolfe (FW) method for static vehicular
traffic and telecom routing. The FW method has been the dominating method for
these problem types, but due to its slow asymptotic convergence it has been
considered dead by methods oriented researchers. However, the recent
introduction of conjugate FW methods has shown that it is still viable, and in
fact the winner on multi-core computers. In this paper, we show how to speed up
the FW iterations, by updating the subproblems in the FW method, instead of
solving them from scratch. The subproblem updating is achieved by viewing the
subproblems as network flow problems with a threaded representation of the
shortest path trees. In addition, we introduce a new technique, thread
following, implying that a single traversal of the thread is enough to find a
new shortest path tree. Our computational tests show that very few nodes in
practice are visited more than once when searching for improving arcs.
Moreover, we update also the all-or-nothing solutions of the subproblems,
resulting in significantly reduced loading times. For a set of standard test
problems, we observe speedups in the region of 25–50% for the subproblem
updating FW method, compared to the traditional non-updating version. We
typically achieve higher speedups for more difficult problems and converged
solutions