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Precarious lives, practices and spaces : an investigation into homelessness and alternative uses of public spaceGesuelli, Fabrizio January 2018 (has links)
The aim of this doctoral thesis is to investigate the practices of rough sleeping and inhabiting public space, with a focus on the modern city of Rome. By inhabiting public spaces, people who are homeless expose their private sphere to public view. Paradoxically, this public exposure of the private becomes a means of exclusion according to Judith Butler and Athena Athanasiou (2013). Scholars acknowledge public space as constructed by the actions that people carry out in public (Lefebvre 1991; Tschumi 1996; Harvey 2012; Jon Goodbun et al. 2014). People who are homeless certainly contribute to the construction of public space (Petty 2016). However, as asserted by architectural scholar Gill Doron, certain practices 'reveal how the public space is restricted to a very small spectrum of activities, and how many other activities are not permitted' (Doron 2000, p.254). These practices put into question what public these spaces are designed and designated for, questioning why only some activities are regarded as public and why some others take place only at night when spaces are temporary urban voids. Rough sleeping in Rome takes place mostly at night, exposing the city to its own fragilities and contradictions. Public space emerges as precarious. It is defned by social and cultural boundaries, within which urban practices alternate one with the other. These are irreconcilable poles within a parallax gap (Žižek 2009). The theoretical scaffolding of the thesis is structured alongside two other transgressive case studies: Pussy Riot's occupation in Moscow and my interviews with parkour practitioners. These cases have been investigated in comparison with homelessness in order to highlight aspects concerning occupation of space as a performative action under precarious circumstances (precarity). The literary review is combined with auto-ethnographical studies I conducted with a community of rough sleepers, comprising 20-40 members who inhabit a portico area nearby St Peter's Square in Rome. I also ran focus groups, individual interviews and project presentations to people who either are involved in charitable bodies that deal with homelessness or are part of the general public, such as passers-by in St Peter's Square. This study has revealed a series of aspects concerning the negotiation of public space and the role of agency and mediation. This study has stimulated questions concerning the role design can play in discourses of social innovation and inclusion. The research conducted has also outlined diffculties concerning the range of data and the possible response to the many voices heard. How can design re-imagine the centre ground between alternative practices in space? By highlighting the centre as precarious, is it possible to fnd a way of re-thinking the centre? On the basis of this study, the aim of the research has been to look at the state of the gap between these alternative poles, investigating and exploring the concept of precarity. This suggests the possibility of redefning concepts of mediation, social inclusion and architectural activism, articulated further through a series of speculative projects, concluding with the presentation of a 'precarious' object I designed together with the community of rough sleepers in St Peter's Square and COTRAD onlus (a charitable body based in Rome).
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AMO: Ateliê Móvel Oficial / Oficial Mobille StudioRaíssa Moraes 22 March 2013 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Este texto é uma fabulação que cumpre papel de revelar um processo de trabalho em arte ao longo de dois anos. Trata-se de um percurso teórico-poético percorrido a partir da descoberta/invenção de um ateliê de criação em meio a minha residência. Um quadrado de 2x2 metros demarcado por sobreposição = fita amarela. Instaurado em divergentes contextos paisagísticos = casa, quarto de hotel, estúdio de dança, galeria de arte, palco, cidade. Trata de habitar os mesmos friccionando esfera de vivência pessoal e sítio específico de acontecimento. No texto, tem lugar reflexões pessoais a partir do trabalho, articulada a outros artistas (como Lygia Clark, Angel e Klauss Vianna, Antonin Artaud, Yves Klein, Min Tanaka, Tadashi Endo) e teóricos (dentre eles Hannah Arendt e Michel Foucault), compondo diferentes tons de fala produzidos ao longo desse período de trabalho / This essay is a fabulation that presents an art work over two years. It is a theoretical-poetic way, coursed from the discovery/invention of a creation studio inside my residence. A square of 2x2m made by superposition = yellow tape, done in different landscape contexts = house, hotel room, dance studio, art gallery, theater stage, city. The intention is to inhabit it rubbing a sphere of personal experiences and a specific site of happening. In the text, personal reflections take place from the art work, articulated with other artists (as Lygia Clark, Angel e Klauss Vianna, Antonin Artaud, Yves Klein, Min Tanaka, Tadashi Endo) and theorists (Hannah Arendt e Michael Foucault), composing different kinds of speech produced along this work period
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Pra?a: lugar de lazer: rela??es entre caracter?sticas ambientais e comportamentais na Pra?a Kalina Maia Natal RNLiberalino, Cintia Camila 19 April 2011 (has links)
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Previous issue date: 2011-04-19 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Nowadays, the urban chaos brings some problems to the citizens such as mental fatigue,
irritability and lack of attention, emphasizing the need for open urban spaces, capable to
contribute to the restoration of physical and mental balance of people. By the variety of
alternative uses available, many of them related to the stimulus of entertainment
activities, the squares have been identified as restorative environments, especially by its
potential as a place of leisure. In this context, the objective of this dissertation is to
understand the use of the square as leisure environment, by a square in Natal RN,
establishing the relationship between environmental and behavioral characteristics.
More specifically, I attempt to identify the major activities that happen there, the people
that develop them and the spatial and temporal configurations of this occupation.
Among the 290 squares available in the city, the Kalina Maia Square was selected,
which is located in the district of Lagoa Nova. The case study chosen was based on
criteria relating to scale, shape, location on the urban environment, variability of uses
and conservation status. In the study were used behavioral mapping place-centered and
people-centered, behavior trace analysis and 14 interviews. The results show that the
square is used by people from different ages and social classes, subdivided into groups
with specific days and times. These users are usually engaged in activities related to
various types of leisure, with sports predominance. The relationship between spatial
configuration and behavior shows that there is a sectorization of uses, being possible to
identify the environmental characteristics that most favor observed activities, especially
in relation to shading and presence of furniture and equipment. Moreover, throughout
the day it appears that the affordances inherent to the various fixed objects on the square
are decoded differently by various categories of users, by giving them insights that help
the development of leisure activities that characterize each group / Atualmente, o caos urbano traz aos moradores das cidades problemas como fadiga
mental, irritabilidade e falta de aten??o, acentuando a necessidade de espa?os urbanos
abertos, capazes de contribuir para a restaura??o do equil?brio f?sico e mental das
pessoas. Pela variedade das alternativas de uso oferecidas, muitas das quais relacionadas
ao est?mulo de atividades de entretenimento, as pra?as t?m sido apontadas como
ambientes restauradores, principalmente pelo seu potencial enquanto lugar de lazer.
Nesse contexto, o objetivo geral desta disserta??o ? a compreens?o do uso da pra?a
como ambiente de lazer, tomando como refer?ncia o estudo de uma pra?a de Natal RN,
estabelecendo a rela??o entre suas caracter?sticas ambientais e comportamentais. Mais
especificamente, busco identificar as principais atividades que ali acontecem, as pessoas
que as desempenham e as configura??es espaciais e temporais dessa ocupa??o. Dentre
290 pra?as existentes na cidade, foi selecionada a Pra?a Kalina Maia, localizada no
bairro de Lagoa Nova. A escolha do estudo de caso recorreu a crit?rios relativos ?
escala, forma, localiza??o na malha urbana, variabilidade de usos e estado de
conserva??o. No estudo utilizei mapeamento comportamental centrado no lugar e
centrado nas pessoas, an?lise de vest?gios de comportamento e 14 entrevistas. Os
resultados revelam que a pra?a ? utilizada por pessoas de varias idades e classes sociais,
subdivididas em grupos com dias e hor?rios espec?ficos. Estes usu?rios geralmente se
envolvem em atividades ligadas a v?rios tipos de lazer, com predomin?ncia do
esportivo. A rela??o entre configura??o espacial e comportamento mostra haver uma
setoriza??o dos usos, sendo poss?vel identificar as caracter?sticas ambientais que mais
favorecem algumas das atividades observadas, sobretudo relacionadas ao sombreamento
e ? presen?a de mobili?rio e equipamentos. Al?m disso, ao longo do dia verifica-se que
as affordances inerentes aos diversos objetos fixos presentes no local s?o decodificadas
diferentemente pelas v?rias categorias de usu?rios, proporcionando a eles entendimentos
que favorecem o desenvolvimento das atividades de lazer que caracterizam cada grupo
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Adsor??o de Mn (II) e Zn (II) em solu??es aquosas usando perlita expandida revestida com quitosanaSantos, Elisama Vieira dos 05 July 2011 (has links)
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Previous issue date: 2011-07-05 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / In this work, chitosan was used as a coating of pure perlite in order to increase
the accessibility of the groups OH- e NH2+the adsorptionof ions Mn2+ e Zn2+.The
characterization results of the expanded perlite classified as microporous and whose
surface area 3,176 m2 g-1after the change resulted in 4,664 m2g-1.From the thermogravimetry(TG) it was found that the percentage
of coating was34,3%.The infrared analysis can prove the presence of groups Si-OH, Si-O e Al-O-Siresulting from the perlite and C=O, NH2and OH characterization of
chitosan. The experiments on experiments on the adsorption of Mn and Zn were
performed in the concentration range of10 a 50 mgL-1and the adsorption capacity inpH
5,8 e 5,2 was 19,49 and 23,09 mgg-1to 25 oC,respectively.The adsorption data were best
fitted to Langmuir adsorption model to Langmuir adsorption model
for both metalionsisindicative of monolayer adsorption. The kinetics of
adsorption were calculated from the equation of Lagergren fitting the model pseudo-second-order for all initial concentrations, suggesting that adsorption of ions Mn2+ and
Zn2+ follows the kinetics of pseudo-second-order
and whose constant Speedk2(g/mg.min) are 0,105 e 3,98 and capacity and maximum
removal qe 4,326 e 3,348,respectively.In this study we used a square wave
voltammetry cathodic stripping voltammetry to quantify the adsorbed ions,
and the working electrode glassy carbon, reference
electrode silver / silver chloride and a platinum auxiliary electrode. The attainment of
the peaks corresponding to ions Mn2+ and Zn2+ was evaluated in and electrochemical
cell with a capacity of 30 mL using a buffer system (Na2HPO4/NaH2PO4)at pH 4 and
was adjusted with solutionsH3PO4 0,1molL-1and NaOH 0,1 molL-1and addition of the
analyte has been a cathodic peak in- 0,873 Vand detection limit of2,55x10-6molL-1para
Zn.The dough used for obtaining the adsorption isotherm was 150 mg and reached in
120 min time of equilibrium for both metal
ions.The maximum adsorption for 120 min with Mn concentration 20 mgL-1 and Zn 10
mgL-1,was91, 09 e 94, 34%, respectively / Nesse trabalho a quitosana foi utilizada como revestimento da perlita expandida
pura com o objetivo de aumentar a acessibilidade dos grupos OH- e NH2+ na adsor??o
dos ?ons Mn2+ e Zn2+. A perlita expandida foi classificada como microporoso com uma
?rea superficial de 3,176m2 g-1 e ap?s modifica??o resultou em 4,664m2 g-1. A partir da
Termogravimetria (TG) verificou-se que o percentual de revestimento foi de 37,5%. A
an?lise de infravermelho comprovou a presen?a dos grupos Si-OH, Si-O e Al-O-Si
decorrentes da perlita e C=O, NH2 e OH caracter?sticos da quitosana. Os experimentos
na adsor??o de Mn2+ e Zn2+ foram realizados no intervalo de concentra??o de 10 a 50
mg L-1 e acapacidade de adsor??o em pH 5,2 e 5,8 foi de 23,09 e 19,49 mg g-1 a 25 oC,
respectivamente. Os dados de adsor??o se ajustaram melhor ao modelo de adsor??o de
Langmuir para ambos os c?tions met?licos sendo indicativo de adsor??o f?sica em
monocamada.As constantes de velocidade de adsor??o foram calculadas a partir da
equa??o Lagergren se ajustando ao modelo de pseudo-segunda-ordem para todas as
concentra??es iniciais, sugerindo que a adsor??o dos ?ons Mn2+ e Zn2+ segue a cin?tica
de pseudo-segunda-ordem e cujas constantes de velocidade k2(g/mg.min) s?o 0,105 e
3,98 e capacidade m?xima de remo??o qe 4,326 e 3,348 mg g-1, respectivamente.
Utilizou-se a voltametria de onda quadrada de redissolu??o cat?dica para a
quantifica??o dos ?ons adsorvidos, com o eletrodo de trabalho de carbono v?treo,
eletrodo de refer?ncia prata/cloreto de prata e um eletrodo auxiliar de platina. A
obten??o dos picos correspondente aos ?ons Mn2+ e Zn2+ foi avaliado em uma c?lula
eletroqu?mica com capacidade para 30 mL utilizando um sistema tamp?o
(Na2HPO4/NaH2PO4) cuja concentra??o 0,1 mol L-1em pH 4, sendo ajustado com
solu??es H3PO4 0,1 mol L-1e NaOH 0,1 mol L-1e adi??o do analito, tendo verificado um
pico cat?dico em 0,873 V com limite de detec??o de Mn 7,76x10-7 mol L-1 e um pico
an?dico de -1,1 V e limite de detec??o de 2,55x10-6mol L-1 para Zn2+.A massa utilizada
para a obten??o das isotermas de adsor??o foi de 150 mg, tendo atingido o tempo de
equil?brio de 120 min para ambos ?ons met?licos. A m?xima adsor??o em 120 min para
Mn2+ com concentra??o de 20 mg L-1 e Zn 10 mg L-1, foi de 91,09 e 94,34%
,respectivamente
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Raiz quadrada de matrizes de ordem 2x2 / Square root of matrices of order 2x2Luz, B. R. M 07 March 2014 (has links)
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Previous issue date: 2014-03-07 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Mathematics is an essential subject today, with the most varied applications. However,
certain mathematical de nitions depends on the prerequisites. Thinking about it,
this work deals on a method of calculating square root matrices of order 2.
As presented de nitions are organized in a gradual way. For this we will use some
de nitions known as multiplication of matrices, determinants and matrix diagonalization. / A matemática é uma disciplina essencial nos dias atuais, com as mais variadas aplicações. Porém, certas defi nições matemáticas dependem de pré-requisistos. Pensando nisso, este trabalho trata sobre um método de calcular raiz quadrada de matrizes de ordem 2. As de nições apresentadas estão organizados de forma gradativa. Para isso usaremos algumas de nições conhecidas como multiplicação de matrizes, determinantes e diagonalização de matrizes.
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Investigação do comportamento eletroquímico do inseticida fipronil e desenvolvimento de metodologia eletroanalítica / Investigation of the electrochemical behavior of the insecticide fipronil and development of electroanalytical methodologyRaquel Bonatto do Amaral 25 May 2012 (has links)
Essa tese de doutorado apresenta o estudo eletroquímico da oxidação do inseticida fipronil bem como o desenvolvimento de metodologias analíticas para a determinação deste composto em amostras de águas naturais. Os experimentos foram realizados sobre os eletrodos de compósito grafite-poliuretana (GPU) e carbono vítreo modificado com nanotubos de carbono de paredes múltiplas (GC-MWCNTs) utilizando a Voltametria de Onda Quadrada (SWV). A Voltametria Cíclica (CV) foi utilizada para diagnosticar o grau de reversibilidade da reação de oxidação do inseticida assim como a natureza do transporte do material eletroativo para a superfície dos eletrodos. Os resultados dos estudos da oxidação eletroquímica do fipronil utilizando o eletrodo de GPU mostraram que a oxidação do fipronil apresenta um em 0,70 V (vs. EAg/AgCl) e ocorre de forma totalmente irreversível e controlada por adsorção das espécies na superfície do eletrodo. Foram obtidas curvas analíticas para o fipronil no intervalo de 2,0 a 14,0 x 10-5 mol L-1, resultando um limite de detecção (LD) de 139 µg L-1 e Limite de Quantificação (LQ) de 480 µg L-1. Para a oxidação do fipronil no eletrodo GC-MWCNTs os resultados mostraram que a oxidação do fipronil apresenta apenas um pico em 0,50 V (vs. EAg/AgCl) e ocorre de forma totalmente irreversível e controlado por difusão a adsorção das espécies na superfície do eletrodo. Os LD e LQ obtidos foram de 26 µg L-1 e 147 µg L-1, respectivamente. O estudo por eletrólise a potencial controlado revelou que a oxidação do inseticida fipronil envolve a participação de um elétron. A metodologia desenvolvida para ambos os eletrodos foi aplicada em amostras de águas naturais, testes de recuperação foram realizados mostrando eficiência de recuperação 96,0% para o eletrodo de GPU e de 94,6% para o eletrodo de GC-MWCNTs. / In this thesis a study of the electrochemical oxidation of the insecticide fipronil and the development of analytical methodologies for the determination of this compound in natural water samples is presented. The experiments were performed at graphite-polyurethane composite electrodes (GPU) and a glassy carbon electrode modified with multi-walled carbon nanotubes (MWCNTs-GC). The electrodes were caracterized using square wave voltammetry (SWV). Cyclic voltammetry (CV) was used to diagnose the degree of reversibility of the oxidation reaction of the insecticide as well as the nature of the transport of the electroactive material to the surface of the electrodes. The electrochemical oxidation of fipronil studies using the GPU electrode showed that fipronil oxidation presents a peak at 0.70 V (vs. EAg/AgCl) which is totally irreversible and controlled by adsorption of species on the electrode surface. Analytical curves were obtained for fipronil in the range 2.0 to 14 x 10-5 mol L-1, with a detection limit (LD) of 139 µg L-1 and a quantification limit (LQ) of 480 µg L-1. For the oxidation of fipronil in the GC-MWCNTs electrode the results showed that fipronil oxidation presents a peak at 0.50 V (vs. EAg/AgCl) which is totally irreversible and diffusion controlled the adsorption of species on the electrode surface. The LD and LQ were obtained 26 µg L-1 and 147 µg L-1, respectively. The study by controlled potential electrolysis showed that oxidation of the insecticide fipronil involves the participation of one electron. The methodology developed for both electrodes was applied to natural water samples, recovery tests were performed showing recovery efficiency of 96.0% for the GPU electrode and 94.6% for MWCNTs-GC electrode.
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Forecasting of intermittent demandSyntetos, Argyrios January 2001 (has links)
This thesis explores forecasting for intermittent demand requirements. Intermittent demand occurs at random, with some time periods showing no demand. In addition, demand, when it occurs, may not be for a single unit or a constant size. Consequently, intermittent demand creates significant problems in the supply and manufacturing environment as far as forecasting and inventory control are concerned. A certain confusion is shared amongst academics and practitioners about how intermittent demand (or indeed any other demand pattern that cannot be reasonably represented by the normal distribution) is defined. As such, we first construct a framework that aims at facilitating the conceptual categorisation of what is termed, for the purposes of this research, “non-normal” demand patterns. Croston (1972) proposed a method according to which intermittent demand estimates can be built from constituent elements, namely the demand size and inter-demand interval. The method has been claimed to provide unbiased estimates and it is regarded as the “standard” approach to dealing with intermittence. In this thesis we show that Croston’s method is biased. The bias is quantified and two new estimation procedures are developed based on Croston’s concept of considering both demand sizes and inter-demand intervals. Consequently the issue of variability of the intermittent demand estimates is explored and finally Mean Square Error (MSE) expressions are derived for all the methods discussed in the thesis. The issue of categorisation of the demand patterns has not received sufficient academic attention thus far, even though, from the practitioner’s standpoint it is appealing to switch from one estimator to the other according to the characteristics of the demand series under concern. Algebraic comparisons of MSE expressions result in universally applicable (and theoretically coherent) categorisation rules, based on which, “non-normal” demand patterns can be defined and estimators be selected. All theoretical findings are checked via simulation on theoretically generated demand data. The data is generated upon the same assumptions considered in the theoretical part of the thesis. Finally, results are generated using a large sample of empirical data. Appropriate accuracy measures are selected to assess the forecasting accuracy performance of the estimation procedures discussed in the thesis. Moreover, it is recognised that improvements in forecasting accuracy are of little practical value unless they are translated to an increased customer service level and/or reduced inventory cost. In consequence, an inventory control system is specified and the inventory control performance of the estimators is also assessed on the real data. The system is of the periodic order-up-to-level nature. The empirical results confirm the practical validity and utility of all our theoretical claims and demonstrate the benefits gained when Croston’s method is replaced by an estimator developed during this research, the Approximation method.
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Policy and Practice Concerning Essay-Grading Criteria in Developmental English and College-Level English Programs in Tennessee Community Colleges.Wolford, Walter Paul 01 May 2000 (has links)
The criteria used to grade college essays have been the subject of research for over three decades. Using quantatative data, this study investigated the differences in essay-grading criteria and essay-grading policy among full-time faculty members who teach English composition in Tennessee's community colleges.
This study revealed beliefs about the importance of essay-grading criteria and beliefs about written and unwritten essay-grading policies among those who teach developmental English, college-level English, and those who teach both levels of English. This study hypothesized that there were no differences among the English composition teacher's beliefs about the importance of the twenty essay-grading criteria nor in their beliefs regarding written and unwritten grading policies.
Chi-square analysis of the non-parametric data collected during this study indicated statistically significant differences among the English teachers regarding only one of the essay-grading criteria and no statistically significant differences regarding the essay-grading policies.
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Multipath Channel Considerations in Aeronautical TelemetryGagakuma, Edem Coffie 01 May 2017 (has links)
This thesis describes the use of scattering functions to characterize time-varying multipath radio channels. Channel Impulse responses were measured at Edwards Air Force Base (EAFB) and scattering functions generated from the impulse response data. From the scattering functions we compute the corresponding Doppler power spectrum and multipath intensity profile. These functions completely characterize the signal delay and the time varying nature of the channel in question and are used by systems engineers to design reliable communications links. We observe from our results that flight paths with ample reflectors exhibit significant multipath events. We also examine the bit error rate (BER) performance of a reduced-complexity equalizer for a truncated version of the pulse amplitude modulation (PAM) representation of SOQPSK-TG in a multipath channel. Since this reduced-complexity equalizer is based on the maximum likelihood (ML) principle, we expect it to perform optimally than any of the filter-based equalizers used in estimating received SOQPSK-TG symbols. As such we present a comparison between this ML detector and a minimum mean square error (MMSE) equalizer for the same example channel. The example channel used was motivated by the statistical channel characterizations described in thisthesis. Our analysis shows that the ML equalizer outperforms the MMSE equalizer in estimating received SOQPSK-TG symbols.
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Dynamics of the energy critical nonlinear Schrödinger equation with inverse square potentialYang, Kai 01 May 2017 (has links)
We consider the Cauchy problem for the focusing energy critical NLS with inverse square potential. The energy of the solution, which consists of the kinetic energy and potential energy, is conserved for all time. Due to the focusing nature, solution with arbitrary energy may exhibit various behaviors: it could exist globally and scatter like a free evolution, persist like a solitary wave, blow up at finite time, or even have mixed behaviors. Our goal in this thesis is to fully characterize the solution when the energy is below or at the level of the energy of the ground state solution $W_a$. Our main result contains two parts.
First, we prove that when the energy and kinetic energy of the initial data are less than those of the ground state solution, the solution exists globally and scatters.
Second, we show a rigidity result at the level of ground state solution. We prove that among all solutions with the same energy as the ground state solution, there are only two (up to symmetries) solutions $W_a^+, W_a^-$ that are exponential close to $W_a$ and serve as the threshold of scattering and blow-up. All solutions with the same energy will blow up both forward and backward in time if they go beyond the upper threshold $W_a^+$; all solutions with the same energy will scatter both forward and backward in time if they fall below the lower threshold $W_a^-$.
In the case of NLS with no potential, this type of results was first obtained by Kenig-Merle \cite{R: Kenig focusing} and Duyckaerts-Merle \cite{R: D Merle}. However, as the potential has the same scaling as $\Delta$, one can not expect to extend their results in a simple perturbative way. We develop crucial spectral estimates for the operator $-\Delta+a/|x|^2$, we also rely heavily on the recent understanding of the operator $-\Delta+a/|x|^2$ in \cite{R: Harmonic inverse KMVZZ}.
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