19 research outputs found
Including time in a travel demand model using dynamic discrete choice
Activity based travel demand models are based on the idea that travel is derived from the
demand to participate in different activities. Predicting travel demand should therefore include
the prediction of demand for activity participation. Time-space constraints, such as working
hours, restricts when and where different activities can be conducted, and plays an important
role in determining how people choose to travel. Travelling is seen as a possibly costly link between
different activities, that also implicitly leads to missed opportunities for activity participation.
With a microeconomic foundation, activity based models can further be used for appraisal
and for accessibility measures. However, most models up to date lack some dynamic consistency that, e.g., might make it hard to
capture the trade-off between activity decisions at different times of the day. In this paper, we show how dynamic discrete choice theory can be used to formulate a travel demand model which includes choice of departure time for all trips, as well as number of trips, location, purpose and mode of transport. We estimate the model on travel diaries and show that the it is able to reproduce the distribution of, e.g., number of trips per day, departure times and travel time distributions
Novel bisphosphonate-based cathepsin K-triggered compound targets the enthesis without impairing soft tissue-to-bone healing
Background: Osteoadsorptive fluorogenic sentinel 3 (OFS-3) is a recently described compound that contains a bone-targeting bisphosphonate (BP) and cathepsin K (Ctsk)-triggered fluorescence signal. A prior study in a murine Achilles repair model demonstrated its effectiveness at targeting the site of tendon-to-bone repair, but the intrinsic effect of this novel bisphosphonate chaperone on tendon-to-bone healing has not been previously explored. We hypothesized that application of this bisphosphonate-fluorophore cargo conjugate would not affect the biomechanical properties or histologic appearance of tendon-bone repairs.Materials and Methods: Right hindlimb Achilles tendon-to-bone repair was performed on 12-week old male mice. Animals were divided into 2 groups of 18 each: 1) Achilles repair with OFS-3 applied directly to the repair site prior to closure, and 2) Achilles repair with saline applied prior to closure. Repaired hindlimbs from 12 animals per group were harvested at 6 weeks for biomechanical analysis with a custom 3D-printed jig. At 4 and 6 weeks, repaired hindlimbs from the remaining animals were assessed histologically using H&E, immunohistochemistry (IHC) staining for the presence of Ctsk, and second harmonic generation (SHG) imaging to evaluate collagen fibers.Results: At 6 weeks, there was no significant difference in failure load, stiffness, toughness, or displacement to failure between repaired hindlimbs that received OFS-3 versus saline. There was no difference in tissue healing on H&E or Ctsk staining on immunohistochemistry between animals that received OFS-3 versus saline. Finally, second harmonic generation imaging demonstrated no difference in collagen fiber parameters between the two groups.Conclusion: OFS-3 did not significantly affect the biomechanical properties or histologic appearance of murine Achilles tendon-to-bone repairs. This study demonstrates that OFS-3 can target the site of tendon-to-bone repair without causing intrinsic negative effects on healing. Further development of this drug delivery platform to target growth factors to the site of tendon-bone repair is warranted
Utbildning i Kina : Om bakgrund och utformning av världens största moderna utbildningsväsende
Sett till antalet studenter har Kina idag världens största utbildningssystem, och landet står inför den formidabla utmaningen att erbjuda utbildning till en femtedel av jordens befolkning. Denna uppsats undersöker utformningen av det kinesiska utbildningssystemet. Först ur ett historiskt perspektiv, där i huvudsak det konfucianska utbildningsväsendet och Mao-Kinas skolsystem berörs. Sedan ur ett samtida perspektiv, vilket utgör huvuddelen av uppsatsen. Här ämnar jag ge en överblick till vad som har åstadkommits, hur skolsystemet är uppbyggt och hur det fungerar i praktiken. Uppsatsen tar också upp vilka svårigheter skolan står inför, samt undersöker regeringens framtidsplaner för skolan och de generella framtidsutsikterna
Standardiserad förtätning med koncepthus
Title: Standardized densification with concept house Author: Oskar Sundberg, Bachelor of Science in Engineering with architecture , Faculty of Engineering LTH at Lund University Supervisor: Radhlinah Aulin, Department of Construction, Faculty of Engineering LTH at Lund University Rikard Nilsson, Department of Construction, Faculty of Engineering LTH at Lund University Exminer: Stefan Olander, Department of Construction, Faculty of Engineering LTH at Lund University Background: Already in the late 19th century, the population growth in the cities began to increase. To densify cities existing urban areas was previously considered inappropriate and instead an expansion of the cities was encouraged. Today, the urban sprawl is being questioned and the benefits of densification are taken into account for a more sustainable urban development. Research questions: - Is it possible to achieve a more sustainable urban development through densification? - What are the advantages and disadvantages of standardize city densification? - Is a solution with concept houses with different designs applicable in practice? Purpose and goals: The purpose of this thesis is to study the prerequisites for a concept house with a choice of design for densification projects. The goal is to provide solutions that include different design choices that are recommended to use within the various components. Method: This study will use qualitative methods with the purpose of gaining a understandings of densification in city areas. The study is based on a literature study and three case studies where qualitative interviews and observations are used to collect information. Conclusion: - Theoretically, urban densification is a good option for achieving a sustainable urban development. However, the study determines that it is hard to identify the consequences that may arise in practice. The conclusion can, nevertheless, be drawn that the observed cities of, Malmo¨, Lund and Kristianstad, can be densified with the intention of a more sustainable city. - With well-conducted observations, the study has developed a range of design choices to a standardized building with the potential to architecturally fit into many different urban structures. - A selection of different designs on a standardized building enables a dialogue between the involved stakeholders, regardless of their previous knowledge of construction projects, to be carried out at an initial stage. - The study has not examined the economic aspects, but the analysis indicates that the choice of building architecture can result in a cost increase. Thus, the purpose of a lower total cost of the project, compared to the location-based, can be lost