892 resultados para Information science
Resumo:
The p-median model is used to locate P facilities to serve a geographically distributed population. Conventionally, it is assumed that the population patronize the nearest facility and that the distance between the resident and the facility may be measured by the Euclidean distance. Carling, Han, and Håkansson (2012) compared two network distances with the Euclidean in a rural region witha sparse, heterogeneous network and a non-symmetric distribution of thepopulation. For a coarse network and P small, they found, in contrast to the literature, the Euclidean distance to be problematic. In this paper we extend their work by use of a refined network and study systematically the case when P is of varying size (2-100 facilities). We find that the network distance give as gooda solution as the travel-time network. The Euclidean distance gives solutions some 2-7 per cent worse than the network distances, and the solutions deteriorate with increasing P. Our conclusions extend to intra-urban location problems.
Resumo:
Objective: To develop a method for objective quantification of PD motor symptoms related to Off episodes and peak dose dyskinesias, using spiral data gathered by using a touch screen telemetry device. The aim was to objectively characterize predominant motor phenotypes (bradykinesia and dyskinesia), to help in automating the process of visual interpretation of movement anomalies in spirals as rated by movement disorder specialists. Background: A retrospective analysis was conducted on recordings from 65 patients with advanced idiopathic PD from nine different clinics in Sweden, recruited from January 2006 until August 2010. In addition to the patient group, 10 healthy elderly subjects were recruited. Upper limb movement data were collected using a touch screen telemetry device from home environments of the subjects. Measurements with the device were performed four times per day during week-long test periods. On each test occasion, the subjects were asked to trace pre-drawn Archimedean spirals, using the dominant hand. The pre-drawn spiral was shown on the screen of the device. The spiral test was repeated three times per test occasion and they were instructed to complete it within 10 seconds. The device had a sampling rate of 10Hz and measured both position and time-stamps (in milliseconds) of the pen tip. Methods: Four independent raters (FB, DH, AJ and DN) used a web interface that animated the spiral drawings and allowed them to observe different kinematic features during the drawing process and to rate task performance. Initially, a number of kinematic features were assessed including ‘impairment’, ‘speed’, ‘irregularity’ and ‘hesitation’ followed by marking the predominant motor phenotype on a 3-category scale: tremor, bradykinesia and/or choreatic dyskinesia. There were only 2 test occasions for which all the four raters either classified them as tremor or could not identify the motor phenotype. Therefore, the two main motor phenotype categories were bradykinesia and dyskinesia. ‘Impairment’ was rated on a scale from 0 (no impairment) to 10 (extremely severe) whereas ‘speed’, ‘irregularity’ and ‘hesitation’ were rated on a scale from 0 (normal) to 4 (extremely severe). The proposed data-driven method consisted of the following steps. Initially, 28 spatiotemporal features were extracted from the time series signals before being presented to a Multilayer Perceptron (MLP) classifier. The features were based on different kinematic quantities of spirals including radius, angle, speed and velocity with the aim of measuring the severity of involuntary symptoms and discriminate between PD-specific (bradykinesia) and/or treatment-induced symptoms (dyskinesia). A Principal Component Analysis was applied on the features to reduce their dimensions where 4 relevant principal components (PCs) were retained and used as inputs to the MLP classifier. Finally, the MLP classifier mapped these components to the corresponding visually assessed motor phenotype scores for automating the process of scoring the bradykinesia and dyskinesia in PD patients whilst they draw spirals using the touch screen device. For motor phenotype (bradykinesia vs. dyskinesia) classification, the stratified 10-fold cross validation technique was employed. Results: There were good agreements between the four raters when rating the individual kinematic features with intra-class correlation coefficient (ICC) of 0.88 for ‘impairment’, 0.74 for ‘speed’, 0.70 for ‘irregularity’, and moderate agreements when rating ‘hesitation’ with an ICC of 0.49. When assessing the two main motor phenotype categories (bradykinesia or dyskinesia) in animated spirals the agreements between the four raters ranged from fair to moderate. There were good correlations between mean ratings of the four raters on individual kinematic features and computed scores. The MLP classifier classified the motor phenotype that is bradykinesia or dyskinesia with an accuracy of 85% in relation to visual classifications of the four movement disorder specialists. The test-retest reliability of the four PCs across the three spiral test trials was good with Cronbach’s Alpha coefficients of 0.80, 0.82, 0.54 and 0.49, respectively. These results indicate that the computed scores are stable and consistent over time. Significant differences were found between the two groups (patients and healthy elderly subjects) in all the PCs, except for the PC3. Conclusions: The proposed method automatically assessed the severity of unwanted symptoms and could reasonably well discriminate between PD-specific and/or treatment-induced motor symptoms, in relation to visual assessments of movement disorder specialists. The objective assessments could provide a time-effect summary score that could be useful for improving decision-making during symptom evaluation of individualized treatment when the goal is to maximize functional On time for patients while minimizing their Off episodes and troublesome dyskinesias.
Resumo:
I avhandlingen behandlas förutsättningar och effekter av kalkylprogramanveckling (KPA). KPA utförs av anvecklare, som fungerar både som användare och utvecklare. Anvecklare har djup verksamhetskunskap och viss verktygskunskap. Systemet, som anvecklaren utvecklar med kalkylprogram, kallas kalkylsystem. Den grundläggande forskningsfrågan i avhandlingen är: "Vilka nya möjligheter får användare att utföra arbetsuppgifter då de själva kan bygga informationssystem?" Avhandlingens syfte är att formulera en begreppsmodell över vilka förutsättningar och effekter, som gäller för kalkylprogramanveckling. Avhandlingens strategi kan sägas vara kvalitativ, hermeneutisk, abduktiv och empirinära. Fyra empiriska studier har genomförts. Empiri har i stor utsträckning styrt studier av relaterad teori. Den praktikgeneriska modellen har använts som referensmodell i avhandlingen, vilket har lett till ett synsätt, som innebär att när anvecklaren anvecklar, agerar han i minst två praktiker, utvecklarpraktiken och huvudpraktiken. Varje praktik har sin uppsättning av förutsättningar, t ex kunskap, normer och verktyg. Den integrerade karaktären på anveckling, gör interaktivitet i utvecklingsarbetet möjlig, vilket i sin tur innebär att anvecklaren snabbt kan växla mellan utveckling och användning. Ökad verktygskunskap kan innebära att anvecklaren ökar sin verksamhetskunskap. Då anvecklarens verksamhetskunskap ökar, ökar möjligheterna att analysera och ifrågasätta verksamheten. Anveckling innebär också att hänsyn kan tas till svårformaliserbara mål och normer, samt att formalisering av tyst kunskap möjliggörs. Anveckling i en miljö med lokala nätverk förenklar möjligheterna att distribuera kalkylsystem för granskning och verifiering. Kalkylsystemets transparens underlättar analys och diskussion. I avhandlingen diskuteras anveckling som ett sätt att hantera kontinuerlig omvärldsförändring på ett sätt som kan innebära omprövning av normer i verksamheten. Då anveckling betraktas som en form av systemutveckling, skiljer sig anveckling starkt från traditionell systemutveckling i och med att anveckling kännetecknas av integration, medan traditionell systemutveckling kännetecknas av specialisering.
Resumo:
Research objectives Poker and responsible gambling both entail the use of the executive functions (EF), which are higher-level cognitive abilities. The main objective of this work was to assess if online poker players of different ability show different performances in their EF and if so, which functions are the most discriminating ones. The secondary objective was to assess if the EF performance can predict the quality of gambling, according to the Gambling Related Cognition Scale (GRCS), the South Oaks Gambling Screen (SOGS) and the Problem Gambling Severity Index (PGSI). Sample and methods The study design consisted of two stages: 46 Italian active players (41m, 5f; age 32±7,1ys; education 14,8±3ys) fulfilled the PGSI in a secure IT web system and uploaded their own hand history files, which were anonymized and then evaluated by two poker experts. 36 of these players (31m, 5f; age 33±7,3ys; education 15±3ys) accepted to take part in the second stage: the administration of an extensive neuropsychological test battery by a blinded trained professional. To answer the main research question we collected all final and intermediate scores of the EF tests on each player together with the scoring on the playing ability. To answer the secondary research question, we referred to GRCS, PGSI and SOGS scores. We determined which variables that are good predictors of the playing ability score using statistical techniques able to deal with many regressors and few observations (LASSO, best subset algorithms and CART). In this context information criteria and cross-validation errors play a key role for the selection of the relevant regressors, while significance testing and goodness-of-fit measures can lead to wrong conclusions. Preliminary findings We found significant predictors of the poker ability score in various tests. In particular, there are good predictors 1) in some Wisconsin Card Sorting Test items that measure flexibility in choosing strategy of problem-solving, strategic planning, modulating impulsive responding, goal setting and self-monitoring, 2) in those Cognitive Estimates Test variables related to deductive reasoning, problem solving, development of an appropriate strategy and self-monitoring, 3) in the Emotional Quotient Inventory Short (EQ-i:S) Stress Management score, composed by the Stress Tolerance and Impulse Control scores, and in the Interpersonal score (Empathy, Social Responsibility, Interpersonal Relationship). As for the quality of gambling, some EQ-i:S scales scores provide the best predictors: General Mood for the PGSI; Intrapersonal (Self-Regard; Emotional Self-Awareness, Assertiveness, Independence, Self-Actualization) and Adaptability (Reality Testing, Flexibility, Problem Solving) for the SOGS, Adaptability for the GRCS. Implications for the field Through PokerMapper we gathered knowledge and evaluated the feasibility of the construction of short tasks/card games in online poker environments for profiling users’ executive functions. These card games will be part of an IT system able to dynamically profile EF and provide players with a feedback on their expected performance and ability to gamble responsibly in that particular moment. The implementation of such system in existing gambling platforms could lead to an effective proactive tool for supporting responsible gambling.
Resumo:
A challenge for the clinical management of advanced Parkinson’s disease (PD) patients is the emergence of fluctuations in motor performance, which represents a significant source of disability during activities of daily living of the patients. There is a lack of objective measurement of treatment effects for in-clinic and at-home use that can provide an overview of the treatment response. The objective of this paper was to develop a method for objective quantification of advanced PD motor symptoms related to off episodes and peak dose dyskinesia, using spiral data gathered by a touch screen telemetry device. More specifically, the aim was to objectively characterize motor symptoms (bradykinesia and dyskinesia), to help in automating the process of visual interpretation of movement anomalies in spirals as rated by movement disorder specialists. Digitized upper limb movement data of 65 advanced PD patients and 10 healthy (HE) subjects were recorded as they performed spiral drawing tasks on a touch screen device in their home environment settings. Several spatiotemporal features were extracted from the time series and used as inputs to machine learning methods. The methods were validated against ratings on animated spirals scored by four movement disorder specialists who visually assessed a set of kinematic features and the motor symptom. The ability of the method to discriminate between PD patients and HE subjects and the test-retest reliability of the computed scores were also evaluated. Computed scores correlated well with mean visual ratings of individual kinematic features. The best performing classifier (Multilayer Perceptron) classified the motor symptom (bradykinesia or dyskinesia) with an accuracy of 84% and area under the receiver operating characteristics curve of 0.86 in relation to visual classifications of the raters. In addition, the method provided high discriminating power when distinguishing between PD patients and HE subjects as well as had good test-retest reliability. This study demonstrated the potential of using digital spiral analysis for objective quantification of PD-specific and/or treatment-induced motor symptoms.
Resumo:
Alison Macrina is the founder and director of the Library Freedom Project, an initiative that aims to make real the promise of intellectual freedom in libraries. The Library Freedom Project trains librarians on the state of global surveillance, privacy rights, and privacy-protecting technology, so that librarians may in turn teach their communities about safeguarding privacy. In 2015, Alison was named one of Library Journal‘s Movers and Shakers. Read more about the Library Freedom Project at libraryfreedomproject.org.
Resumo:
Each year search engines like Google, Bing and Yahoo, complete trillions of search queries online. Students are especially dependent on these search tools because of their popularity, convenience and accessibility. However, what students are unaware of, by choice or naiveté is the amount of personal information that is collected during each search session, how that data is used and who is interested in their online behavior profile. Privacy policies are frequently updated in favor of the search companies but are lengthy and often are perused briefly or ignored entirely with little thought about how personal web habits are being exploited for analytics and marketing. As an Information Literacy instructor, and a member of the Electronic Frontier Foundation, I believe in the importance of educating college students and web users in general that they have a right to privacy online. Class discussions on the topic of web privacy have yielded an interesting perspective on internet search usage. Students are unaware of how their online behavior is recorded and have consistently expressed their hesitancy to use tools that disguise or delete their IP address because of the stigma that it may imply they have something to hide or are engaging in illegal activity. Additionally, students fear they will have to surrender the convenience of uber connectivity in their applications to maintain their privacy. The purpose of this lightning presentation is to provide educators with a lesson plan highlighting and simplifying the privacy terms for the three major search engines, Google, Bing and Yahoo. This presentation focuses on what data these search engines collect about users, how that data is used and alternative search solutions, like DuckDuckGo, for increased privacy. Students will directly benefit from this lesson because informed internet users can protect their data, feel safer online and become more effective web searchers.
Resumo:
In recent decades, library associations have advocated for the adoption of privacy and confidentiality policies as practical support to the Library Code of Ethics with a threefold purpose to (1) define and uphold privacy practices within the library, (2) convey privacy practices to patrons and, (3) protect against potential liability and public relations problems. The adoption of such policies has been instrumental in providing libraries with effective responses to surveillance initiatives such as warrantless requests and the USA PATRIOT ACT. Nevertheless, as reflected in recent news stories, the rapid emergence of data brokerage relationships and technologies and the increasing need for libraries to utilize third party vendor services have increased opportunities for data surveillers to access patrons’ personal information and reading habits, which are funneled and made available through multiple online library service platforms. Additionally, the advice that libraries should “contract for the same level of privacy reflected in their privacy policies” is no longer realistic given that the existence of multiple vendor contracts negotiated at arms length is likely to produce varying privacy terms and even varying definitions of what constitutes personal information (PII). These conditions sharply threaten the effectiveness and relevance of library privacy policies and privacy initiatives in that such policies increasingly offer false comfort by failing to reflect privacy weaknesses in the data sharing landscape and vendor contracts when library-vendor contracts fail to keep up with vendor data sharing capabilities. While some argue that library privacy ethics are antiquated and rendered obscure in the current online sharing economy PEW studies point to pronounced public discomfort with increasing privacy erosion. At the same time, new directions in FTC enforcement raise the possibility that public institutions’ privacy policies may serve as swords to unfair or deceptive commercial trade practices – offering the potential of renewed relevance for library privacy and confidentiality policies. This dual coin of public concern and the potential for enhanced FTC enforcement suggests that when crafting privacy polices libraries must now walk the knife’s edge by offering patrons both realistic notice about the limitations of protections the library can ensure while at the same time publicly holding vendors accountable to library privacy ethics and expectations. Potential solutions for how to walk this edge are developed and offered as a subject for further discussion to assist the modification of model policies for both public and academic libraries alike.
Resumo:
It is a well known fact that librarians, as professionals go, are not among the world's most demonstrative people. I can say that with impunity because I am one. It's one thing for a man to slight his own profession; quite another when someone else presumes to do it. But given that librarians are a placid sort, just mention the phrase "intellectual freedom," or utter the word "censorship," and the usually calm demeanor of the librarian becomes as agitated as the water between Charybdis and Scylla! This article addresses three aspects of the issue of intellectual freedom and attempts to define the difference between the phrases "free speech" and "free expression." First to be explored will be the nature of intellectual freedom as defined by the American Library Association's Intellectual Freedom Manual; second, the underlying philosophy implicit in that expression; and third, an alternative to both the manual, and its philosophical presuppositions.
Resumo:
Current library trends and ongoing shifts are driven by numerous factors including macroeconomic environments, technological impacts, and institutional changes. Strategic needs are as varied as the many individual libraries and their circumstances, but the need is universal for thoughtful leadership in navigating change. While worldlows adapt to changing environments in the short term, long-term shifts require thoughtful leadership and long-range thinking. As libraries and collection management navigate continuing shifts, businesses face similar challenges; this article distills strategies' philosophical underpinnings from library and business scholarship.
Resumo:
This article presents the data-rich findings of an experiment with enlisting patron-driven/demand-driven acquisitions (DDA) of ebooks in two ways. The first experiment entailed comparison of DDA eBook usage against newly ordered hardcopy materials’ circulation, both overall and ebook vs. print usage within the same subject areas. Secondly, this study experimented with DDA ebooks as a backup plan for unfunded requests left over at the end of the fiscal year.
Resumo:
Libraries are caught in the middle—between static or shrinking budgets on one hand and ever-expanding user needs on the other. How did we get here, and where do we go from here? This paper will offer two perspectives: Part I will present survey results about changing Library purchasing habits in light of changing formats, access, business models and user demands. Data from a previous survey on this topic will be compared and updated. Pricing trends and possible futures will be discussed. Part II will briefly trace the history of libraries’ roles in scholarly communication and connecting learners with knowledge. From there, we show an example of phasing in a patron-driven / demand-driven and short-term loan e-book program, complete with incorporating these tools in library instruction, research, and portable device loadability for field work.