Obsolescence determination of network information based on “double-proportion” method

Purpose:It is necessary to determine whether the value of network information exists or not from users’perspective.This study is to develop a new approach,called'double-proportion'method(DPM),to determine the point of information obsolescence.Design/methodology/approach:Firstly,DPM is produced and introduced with statistics in great detail.Secondly,two data sets from Qiangguo Forum and NetEase News are used to validate DPM.Finally,the distributions of lifetime of the two sets are compared and reasons for the differences are revealed.Findings:In Qiangguo Forum,posts with no comments within 17 h can be identified as obsolescence,which indicates that approximately 83%of posts information has died within24 h,92%died within 36 h and almost all died within 54 h;While in NetEase News,news without comments within 28 h can be identified as obsolescence.Research limitations:This study adopted comments as the only behavior indicator,for further study other indicators like page views,republished times need to be used,to exploit better solutions for information obsolescence.Practical implications:According to obsolescence determination,network managers can optimize webpages more rationally,delete aged information in time,preserve valuable information,help search engines ignore aged webpages,optimize reptiles’mechanisms,and help advertisers choose webpages rationally to advertise online.Originality/value:Firstly,DPM is designed from users’perspective to describe the lifetime of information;Secondly,DPM is easy to use.DPM merges and improves former methods by taking the long-tail theory and Pareto principle into consideration.

中文生物学期刊文献老化的分析

本文通过统计1983年和1984年国内生物学期刊引文所发表的时间,描绘了中文生物学期刊文献引用的时间分布曲线,并测定了生物学各专业期刊文献的半衰期。

An empirical research on the field of wireless charging based on patent life length

With the aid of patent life cycle theory,and from the perspective of patent life span,this paper choose the ‘times of citation-time sequence'data of patents as an observation index to research on related patents in the field of wireless charging by applying the adjusted ‘double-proportion'obsolescence method. The research reveals the rules of patent life span in the field of wireless charging,finding that the first 5 years since patents were authorized is the core period for the patents to play their full value,and also discovers the development law of merging technology patents.

The Neue Nationalgalerie by Mies van der Rohe between Preservation and Minimal Improvement

The Neue Nationalgalerie(1968)is considered an icon of the 20th century and part of the legacy of Mies van der Rohe.Almost 50 years after its construction the building showed some physiological decay;however,it has been considered obsolete due to the changing standards of use and comfort of an international art gallery affected also by a growing flux of visitors.The paper investigates the future of such an icon of modern architecture moving from some open issues of the intervention carried out by David Chipperfield started up in 2015 and now in an advanced stage.The refurbishment is pursuing the modernization of the building,but trying to match the historical values with the requirements of climate control and safety.The binomials memories/requirements and authenticity/form are at the base of the investigation.Although the intervention confirms the continuity of original use and it is aimed at keeping the image of the icon,it imposes transformations that belong to very different strategies,sometimes incompatible with the preservation of material meanings and values.The restoration work on modern heritage outlines how new cultural and socio-economic needs confront themselves with respecting/reproducing the appearance of the monument.

Useful Life of Astrophysical Scientific Facilities

Large-scale astrophysical facilities have become increasingly relevant in certain key areas of scientific research but typically require strong financial investments. It is, therefore, crucial to gain a deep understanding of what could be a foreseeable lifespan of a given instrument before providing the required fund to build it. In this paper, we intend to contribute to this understanding with a study of the lifespan of past, current and future observatories and telescopes. The methodology has been based on the compilation of relevant data from twenty telescopes, three of them mounted on space satellites and the other seventeen distributed worldwide. An analysis of the main limiting factors that affect the lifetime of an astrophysical facility is also presented.

计划报废的两面性

早在20世纪中前期的西方大规模生产时,计划报废(Planned obsolescence)这个设计概念就已经被提出,时至今日仍然在不断沿用和发展,这种涉入式的过期手段成为了二战以后西方国家在产品设计领域里的一个显著特点。作为一种设计现象,多角度认识计划报废,对指导设计具有重要的理论和现实意义。

The management of water heritage in Portuguese cities:Recent regeneration projects in Évora,Lisbon,Braga and Guimarães

Given the cultural and environmental potential presented by historical water infrastructures in urban contexts,this article states the evidence of a not much documented urban phenomenon in Portugal,the refurbishment of water heritage protected areas motivated by European-based regeneration projects.By employing a case-study design,four good practices-placed inÉvora,Lisbon,Braga and Guimarães-are chosen to enlighten this growing and aware trend.The assets located there-theÁgua de Prata Aqueduct,theÁguas Livres Aqueduct,the Sete Fontes water-supply system and the Zona de Couros industrial area,respectively-are geographical,historical and culturally characterised,while the projects that concern them are documented by visiting the areas and analysing the available sources.Then,open-data platforms and heritage protection decrees are processed to graphically code the topography,hydrology,urban land use,infrastructures,landmarks and protected areas,employing QGIS free software for Geographic Information Systems.As a result,the four practices are documented,discussed and compared.A table assesses and summarises their pre-existing and currently added values and a series of diagrams illustrates the landscape changes generated.These graphics validate the practices and update the status of the assets,enhancing the rediscovery of the existing landscapes and showing the main challenges and future opportunities faced by these areas.

A methodology for measuring the preservation durability of digital formats

It is now widely recognized that appropriate measures are required for digital preservation to ensure that digital data can be accessed and used currently and in the future.Among all the risks of digital preservation,format obsolescence is one of the most important.There have been several projects or initiatives dealing with the measurement method of format obsolescence risk,but there has been no mechanism to quantify the preservation risk or durability of digital formats based on a self-improving assessment model,executed with the aid of computers.This paper deals with a methodology for measuring the preservation durability of digital formats,especially for their risk assessment.This method is based on a quantitative assessment model for format risk,and can shift the non-quantifiable knowledge or experiences of field experts to a machine identifiable and processible form,or 'risk scores'.Results can be recognized and communicated by computers automatically and formally,which can assist in the automatic/semi-automatic risk management for digital preservation,sharing this quantified knowledge among communities. Because technologies are changing quickly,the quantitative assessment model for risks will not be a status quo situation.Thus,also presented is a method to fine tune the quantitative assessment model for risk of formats through a self-learning and self-improving style.