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Abstract At present, most of the enterprises make use of a set of software system of Enterprise Resource Planning (ERP) in order to improve the internal management, and regards it as the nuclear information system. Their goal is to promote the enterprise's operational benefits (Hong and Kim, 2002) by the synthetic effects. Some enterprises induct do brings certain benefits after using the EPR. However, faces the current violent and competitive environment, the majority of ERP are not able to arrange the uses of resources effectively, which causes the enterprises unable to make the delivery dates of the customers¡¦ orders punctually or causes the enterprises¡¦ original profits reduced due to storing up too much stock for satisfy the delivery dates of the customers¡¦ orders. This research take a T Corporation, one of small and medium manufactures of Taiwan, as an example, this company uses the domestic well-known brand system of ERP as the main information system of the enterprise. After using the producing and managing module of ERP to plan its purchase policy of raw materials for a long time, the material inventory stay at a high level even after several years¡¦ adjustment. In addition, due to the price of copper fluctuated heavily frequently in recent years, not only the inventory cost can¡¦t be controlled well but also the orders are missed usually involving being unable to reflect the cost of raw materials on the customers¡¦ quotes immediately. Therefore, this research takes the System Dynamics which is good at solving the problems of dynamic complexity as a simulated research to practice the models¡¦ constructions and simulations and add the prosperity of system thinking into the business strategy to provides the quantifiable analogue result in order to strengthen the insufficient aspects of products and materials of EPR and to assist the enterprises¡¦ boss to solve those problems of dynamic complexity which are easily been neglect when makes operational strategies.

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Yes / PURPOSE. To compare microperimetric sensitivity around the monocular preferred retinal locus (mPRL) in age-related macular degeneration (AMD) to normative data, and to describe the characteristics of visual field defects around the mPRL in AMD. METHODS. Participants with AMD (total n ¼ 185) were either prospectively recruited (n ¼ 135) or retrospectively reviewed from an existing database (n ¼ 50). Participants underwent microperimetry using a test pattern (37 point, 58 radius) centered on their mPRL. Sensitivities were compared to normative data by spatial interpolation, and conventional perimetric indices were calculated. The location of the mPRL relative to the fovea and to visual field defects was also investigated. RESULTS. Location of mPRL varied approximately 158 horizontally and vertically. Visual field loss within 58 of the mPRL was considerable in the majority of participants (median mean deviation 14.7 dB, interquartile range [IQR] 19.6 to 9.6 dB, median pattern standard deviation 7.1 dB [IQR 4.8–9.0 dB]). Over 95% of participants had mean total deviation worse than 2 dB across all tested locations and similarly within 18 of their mPRL. A common pattern of placing the mPRL just foveal to a region of normal pattern deviation was found in 78% of participants. Total deviation was outside normal limits in this region in 68%. CONCLUSIONS. Despite altering fixation to improve vision, people with AMD exhibit considerable visual field loss at and around their mPRL. The location of the mPRL was typically just foveal to, but not within, a region of relatively normal sensitivity for the individual, suggesting that a combination of factors drives mPRL selection. / This report presents independent research funded by the NIHR

Licentiatavhandling (sammanfattning) Stockholm : Karol. inst., 2005. / Härtill 2 uppsatser.

Title: Ideal Bayesian Observer with reduced detectability map Author: Josef Amemori Department: Department of Software and Computer Science Education Supervisor: Mgr. Filip Děchtěrenko, Department of Software and Computer Science Education Abstract: A computational modeling of the human vision is a challenging task. In recent years, a biologically inspired model Ideal Bayesian Observer was created for the visual search task (Najemnik & Geisler, 2005). The model predicts eye movements when searching for Gabor patch in 1/f noise. In their work, they observed similarity between distributions of fixations and saccades predicted by Ideal Bayesian Observer and distributions of fixations and saccades from a human observer. In this work, we have implemented Ideal Bayesian Observer with degenerated visual field and compared the model with behavior of a human. Keywords: Ideal Bayesian Observer, eye movements, modeling, central scotoma

Le cerveau montre d’étonnantes capacités d’adaptation aux modifications des entrées sensorielles, celles-ci pouvant avoir pour origine une modification de l’environnement ou être liées à une pathologie de l’organe récepteur lui-même. Les techniques d’imagerie fonctionnelle permettent d’étudier l’impact d’une atteinte du récepteur sensoriel du système visuel, la rétine, sur le fonctionnement et les capacités de réorganisation du cortex visuel primaire. Le but de ce travail était d’ouvrir des pistes de recherche sur les conséquences fonctionnelles centrales et périphériques de pathologies oculaires se manifestant toute par un scotome visuel important. Dans un premier temps, nous avons étudié l’organisation fonctionnelle du cortex visuel humain en Imagerie par Résonance Magnétique fonctionnelle (IRMf) à haut champ (3T). Le but de cette étude était de cartographier et de délimiter de manière reproductible les aires visuelles de bas niveau (V1, V2 et V3) par la réalisation de cartes corticales rétinotopiques. Nous avons développé un protocole expérimental spécifique afin d’étudier, chez le sujet sain, les modifications de l’organisation rétinotopique corticale en présence d’une interruption locale de stimulation rétinienne (scotome artificiel). Ce protocole a ensuite été appliqué chez un patient présentant une maculopathie en phase aiguë et après récupération fonctionnelle. Cette étude confirme la possibilité de mesurer sur la surface corticale des zones d’activités différentielles correspondant à une modification localisée de la sensibilité rétinienne et permettra, dans le cas d’atteintes rétiniennes évolutives, d’étudier les phénomènes de plasticité corticale au cours de l’évolution de ces pathologies. Dans un second temps, nous avons mis au point un dispositif d’imagerie optique afin de caractériser l’organisation rétinotopique de l’aire V1 chez le rat. Le développement de cette méthode va nous permettre de lancer deux études importantes. Premièrement, nous étudierons la cinétique des modifications de la carte rétinotopique et de l’activité neuronale afin d’évaluer le rôle respectif des phénomènes de plasticité corticale ou de modification du gain neuronal dans la réorganisation fonctionnelle du cortex visuel après lésion rétinienne. Ces résultats 3 seront à comparer aux données acquises en IRMf chez l’homme. Deuxièmement, cette méthode est le préalable à une étude complémentaire qui a pour but de tester l’impact fonctionnel d‘implants rétiniens chez le rat. Les lésions oculaires impliquent aussi des réorganisations locales, en particulier vasculaires dont les conséquences fonctionnelles sont mal connues. Nous avons donc développé en parallèle des modèles de lésions périphérique permettant l’étude des conséquences sur la rétinotopie d’un scotome induit à la suite d’une atteinte sensorielle périphérique. Ce travail ouvre plusieurs perspectives quant à l’exploration fonctionnelle dans des pathologies comme la DMLA. / The brain shows a high ability to reorganize following alteration of sensorial input that may result from modification of the environment or disease of sensorial organs. Modern functional imagery techniques allow to examine the impact on the visual system of such alterations. The aim of this thesis was to develop new approaches for studying at the cortical level, functional consequences of ocular disease associated with a significant visual scotoma. In the first section of this thesis, we used high-field (3T) functional magnetic resonance imaging (fMRI) to study the cortical functional architecture. Our goal was to map the retinotopic organization of human early visual cortical areas (V1, V2, V3). By this method, we identified modifications of retinotopic organization induced by a focal loss of retinal stimulation (artificial scotoma) and we observed the cortical projections of artificial scotoma on healthy subjects by the mean of a specific stimulus. In the following part of the experimentation, this protocol was used on a patient who showed a maculopathy at the acute stage and after recovery. This study confirms the ability to evaluate the cortical representation (size and location) of a focalized modification of the retinal sensibility threshold and could serve as a basis for the future investigation of cortical plasticity in the visual cortex following retinal diseases. The second section of this thesis was directed to the development of optical imaging intrinsic signals on small animals. Our goals were to characterize the retinotopic organization of rat’s visual cortex. With this method, we will investigate the kinetics of cortical remapping and modifications of the neuronal activity level following retinal lesion. These results will be compared to the data previously acquired by fMRI in humans. Another application of our method will be to study the functional impact of retinal prosthesis. Ocular lesions are associated with local modifications of retinal tissue, and especially with neovascular ingrowth, for which functional consequences have not been totally clarified. We therefore developed models of peripheral lesions, which allow to study the effect of scotoma on retinotopic organization of primary visual cortex after peripheral sensory lesion. This thesis gives some new directions in the functional exploration in retinal disease as Age Related Macular Degeneration (ARMD).

京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第18875号 / 医博第3986号 / 新制||医||1008(附属図書館) / 31826 / 京都大学大学院医学研究科医学専攻 / (主査)教授 森田 智視, 教授 福山 秀直, 教授 大森 治紀 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

Yes / Depictions of vision with AMD in public information material typically show a central region of absolute vision loss. Patients with early and moderate disease frequently do not report this. We aimed to measure how a group of people with AMD perceive everyday scenes in order to produce accurate depictions. We report on six people aged 65-82 years with monocular AMD (visual acuity +0.04 to +1.64 logMAR) and normal vision in the fellow eye. Participants viewed 4 images monocularly, alternating between eyes. The image was digitally altered to approximate participants’ descriptions of their perception with the affected eye. The altered image was viewed with the unaffected eye, and compared with the original image viewed with the affected eye. This was repeated iteratively until a perceptual match was achieved between the modified image/unaffected eye and the original image/affected eye. For five AMD participants with visual acuity +0.04 to +0.50 logMAR the modified images did not resemble those in current public information material. Image modifications required to achieve perceptual similarity with the affected eyes included localised distortion, contrast reduction and blur. Widespread colour desaturation was also required in some cases. One participant with advanced geographic atrophy reported an absolute positive scotoma, similar to existing depictions. Vision in people with AMD may not conform to the common depiction of a central region of absolute vision loss. The accurate representations of AMD patients’ vision produced in this study will enable better understanding of the visual consequences of AMD. / College of Optometrists Postdoctoral Award; National Institute for Health Research Postdoctoral Fellowship