Luis Silva Lopez | Universidad Tecnológica de Chile (original) (raw)

Papers by Luis Silva Lopez

SSRN Electronic Journal, 2019

This research provides evidence on the role of information asymmetry and personal affiliations in... more This research provides evidence on the role of information asymmetry and personal affiliations in housing transactions using a novel dataset that allows observation of detailed information about the property, broker, and seller. Sellers holding a real estate license are found to obtain about 1.6 percent (or $3,200) more for their properties than unlicensed sellers, and sellers personally affiliated to a real estate licensee (e.g., spouses, siblings, parents) also obtain a premium of about the same size, all else equal. There is evidence from appraisal training that knowledge of property valuation further increases the price disparities, while informative public property records reduce price disparities. Agents and personal affiliates appear to use information advantages to time the market and capture capital gains. These new findings provide insights into the behaviors of market participants in asymmetric information environments.

Lecture Notes in Computer Science, 2016

Opportunistic storytelling is an approach to interactive narrative where the AI challenge is to t... more Opportunistic storytelling is an approach to interactive narrative where the AI challenge is to tell a story about what the player is doing, with game play providing the ordinary activity that underlies story events. In this preliminary work, we motivate the need for event prediction within this framework, and describe a machine learning approach to the problem. We report results showing how different feature models can be learned and compared in this context, towards automating model selection.

Amplitude modulated atomic force microscopy (AM-AFM), also known as tapping-AFM, has been applied... more Amplitude modulated atomic force microscopy (AM-AFM), also known as tapping-AFM, has been applied to the quantification of second nano-phases in the AA 7075-T651 aluminum alloy (GP-zones, eta’ and eta phases). Specialized image analysis software was used to obtain statistical information from phase contrast AFM images. The method here described drastically reduces the effort required for sample preparation, contrasted with the one demanded by transmission electron microscopy, minimizing sample handling and reducing the likelihood of losing relevant information due to sample manipulation. The experimental results are compared with those reported by other authors using transmission electron microscopy, traditionally used for nanoparticle quantification.

Solid state precipitation is the main mechanism of strengthening in the aluminum alloy AA 7075 [1... more Solid state precipitation is the main mechanism of strengthening in the aluminum alloy AA 7075 [1]. This phenomenon affects the hardness of the material depending on precipitate concentration, size, and distribution. In this work, phase-contrast atomic force microscopy (PC-AFM) was applied to study changes in  and ’ precipitate size and distribution in the various regions generated transversely to the joint made by friction stir welding. The results show the microstructural variations caused by the thermomechanical effect due to the welding process, and are correlated with Vickers hardness measurements performed by microindentation.

Lecture Notes in Computer Science, 2003

In this paper, the obtained results on iCLEF-2002 are presented. This is the first time that we t... more In this paper, the obtained results on iCLEF-2002 are presented. This is the first time that we try to face up the iCLEF task, and we have used a Passage Retrieval approach, specifically our previously developed system called IR-n. This system previously divides the document in fragments or passages, and after that, the similarity of each passage with the query is measured. Finally, the document that contains the most similar passage is returned as the most relevant document. In the interactive document selection task, we have experimented with this system in the following way, the system only shows the most relevant passage of each document instead of the entire document. In this work, the results obtained with this system are presented, where the relevant passages presented to the user have been automatically translated into Spanish by means of Systran. Moreover, the results are compared with Z-Prise system, which is based on the reading of the entire document.

SSRN Electronic Journal, 2019

This research provides evidence on the role of information asymmetry and personal affiliations in... more This research provides evidence on the role of information asymmetry and personal affiliations in housing transactions using a novel dataset that allows observation of detailed information about the property, broker, and seller. Sellers holding a real estate license are found to obtain about 1.6 percent (or $3,200) more for their properties than unlicensed sellers, and sellers personally affiliated to a real estate licensee (e.g., spouses, siblings, parents) also obtain a premium of about the same size, all else equal. There is evidence from appraisal training that knowledge of property valuation further increases the price disparities, while informative public property records reduce price disparities. Agents and personal affiliates appear to use information advantages to time the market and capture capital gains. These new findings provide insights into the behaviors of market participants in asymmetric information environments.

Lecture Notes in Computer Science, 2008

Lecture Notes in Computer Science, 2016

Opportunistic storytelling is an approach to interactive narrative where the AI challenge is to t... more Opportunistic storytelling is an approach to interactive narrative where the AI challenge is to tell a story about what the player is doing, with game play providing the ordinary activity that underlies story events. In this preliminary work, we motivate the need for event prediction within this framework, and describe a machine learning approach to the problem. We report results showing how different feature models can be learned and compared in this context, towards automating model selection.

Amplitude modulated atomic force microscopy (AM-AFM), also known as tapping-AFM, has been applied... more Amplitude modulated atomic force microscopy (AM-AFM), also known as tapping-AFM, has been applied to the quantification of second nano-phases in the AA 7075-T651 aluminum alloy (GP-zones, eta’ and eta phases). Specialized image analysis software was used to obtain statistical information from phase contrast AFM images. The method here described drastically reduces the effort required for sample preparation, contrasted with the one demanded by transmission electron microscopy, minimizing sample handling and reducing the likelihood of losing relevant information due to sample manipulation. The experimental results are compared with those reported by other authors using transmission electron microscopy, traditionally used for nanoparticle quantification.

Lecture Notes in Computer Science, 2006

This paper introduces a novel unstructured P2P system able to adapt its overlay network topology ... more This paper introduces a novel unstructured P2P system able to adapt its overlay network topology to the load conditions. The adaptation is performed by means of a mechanism which is run by the nodes in the network in an autonomous manner using only local information, so no global coordinator is needed. The aim of this adaptation is to build an efficient topology for the resource discovery mechanism performed via random walks. We present the basis of the adaptation mechanism, along with some simulation results obtained under different conditions. These results show that this system is efficient and robust, even in front of directed attacks.

Solid state precipitation is the main mechanism of strengthening in the aluminum alloy AA 7075 [1... more Solid state precipitation is the main mechanism of strengthening in the aluminum alloy AA 7075 [1]. This phenomenon affects the hardness of the material depending on precipitate concentration, size, and distribution. In this work, phase-contrast atomic force microscopy (PC-AFM) was applied to study changes in  and ’ precipitate size and distribution in the various regions generated transversely to the joint made by friction stir welding. The results show the microstructural variations caused by the thermomechanical effect due to the welding process, and are correlated with Vickers hardness measurements performed by microindentation.

Lecture Notes in Computer Science, 2003

In this paper, the obtained results on iCLEF-2002 are presented. This is the first time that we t... more In this paper, the obtained results on iCLEF-2002 are presented. This is the first time that we try to face up the iCLEF task, and we have used a Passage Retrieval approach, specifically our previously developed system called IR-n. This system previously divides the document in fragments or passages, and after that, the similarity of each passage with the query is measured. Finally, the document that contains the most similar passage is returned as the most relevant document. In the interactive document selection task, we have experimented with this system in the following way, the system only shows the most relevant passage of each document instead of the entire document. In this work, the results obtained with this system are presented, where the relevant passages presented to the user have been automatically translated into Spanish by means of Systran. Moreover, the results are compared with Z-Prise system, which is based on the reading of the entire document.

Lecture Notes in Computer Science, 2008

Lecture Notes in Computer Science, 2006

This paper introduces a novel unstructured P2P system able to adapt its overlay network topology ... more This paper introduces a novel unstructured P2P system able to adapt its overlay network topology to the load conditions. The adaptation is performed by means of a mechanism which is run by the nodes in the network in an autonomous manner using only local information, so no global coordinator is needed. The aim of this adaptation is to build an efficient topology for the resource discovery mechanism performed via random walks. We present the basis of the adaptation mechanism, along with some simulation results obtained under different conditions. These results show that this system is efficient and robust, even in front of directed attacks.

Lecture Notes in Computer Science, 2005

Theory of Computing Systems, 2007

In this paper we start the study of generalizing the Adversarial Queueing Theory (aqt) model towa... more In this paper we start the study of generalizing the Adversarial Queueing Theory (aqt) model towards a continuous scenario in which the usually assumed synchronicity of the evolution is not required anymore. We consider a model, named continuous AQT (caqt), in which packets can have arbitrary lengths, and the network links may have different speeds (or bandwidths) and propagation delays. We show that, in such a general model, having bounded queues implies bounded endto-end packet delays and vice versa. From the network point of view, we show that networks with directed acyclic topologies are universally stable, i.e., stable independently of the protocols and the traffic patterns used in it, and that this even holds for traffic patterns that make links to be fully loaded. Concerning packet scheduling protocols, we show that the well-known lis, sis, ftg and nfs protocols remain universally stable in our model. We also show that the caqt model is strictly stronger than the aqt model by presenting scheduling policies that are unstable under the former while they are universally stable under the latter.

Scandinavian Cardiovascular Journal, 1992

Thirty-five patients who had undergone surgery for non-small cell bronchogenic carcinoma with iso... more Thirty-five patients who had undergone surgery for non-small cell bronchogenic carcinoma with isolated involvement of the chest wall were reviewed. The diagnosis was preoperatively suspected in 80% of cases. En-bloc resection of the invaded chest wall was performed in 25 cases and parietal pleurectomy in ten in which the pleura was easily dissectable from the costal plane. Of the eight patients with major complications in the early postoperative period, six, including the two who died perioperatively, had undergone en-block resection. The 5-year actuarial survival rate was 22% overall and 36% in the patients without lymph node involvement. No significant relationship between survival and type of operation or degree of chest wall invasion was found. Isolated involvement of the chest wall by non-small cell bronchogenic carcinoma does not necessarily contraindicate surgery with curative intent. Parietal pleurectomy is valid in selected cases. Long-term survival depends basically on node involvement.

Proceedings of the National Academy of Sciences, 1977

The ability of three cultured mouse tumor lines to stimulate a cytotoxic response in 5-day cultur... more The ability of three cultured mouse tumor lines to stimulate a cytotoxic response in 5-day cultures of allogeneic lymph node cells was studied with a 51Cr release assay. Two lines of mesenchymal origin, P815 and EL-4, were found to be highly stimulatory, whereas the third cell line, CaD2, a mammary gland epithelial tumor, did not stimulate over a wide range of cell concentration. CaD2 cells were shown to contain major antigens similar to those of P815 cells by the specific lysis of both cells by lymphocytes activated to H-2d-bearing peritoneal cells.UV-irradiated P815-cells, like gamma-irradiated CaD2 cells, did not stimulate a cytotoxic response, but both cell lines were found to stimulate a full and specific response to allogeneic lymph node cells if these mixed cultures were supplemented with a supernatant harvested from concanavalin A-stimulated spleen cells.

SSRN Electronic Journal, 2019

This research provides evidence on the role of information asymmetry and personal affiliations in... more This research provides evidence on the role of information asymmetry and personal affiliations in housing transactions using a novel dataset that allows observation of detailed information about the property, broker, and seller. Sellers holding a real estate license are found to obtain about 1.6 percent (or $3,200) more for their properties than unlicensed sellers, and sellers personally affiliated to a real estate licensee (e.g., spouses, siblings, parents) also obtain a premium of about the same size, all else equal. There is evidence from appraisal training that knowledge of property valuation further increases the price disparities, while informative public property records reduce price disparities. Agents and personal affiliates appear to use information advantages to time the market and capture capital gains. These new findings provide insights into the behaviors of market participants in asymmetric information environments.

Lecture Notes in Computer Science, 2016

Opportunistic storytelling is an approach to interactive narrative where the AI challenge is to t... more Opportunistic storytelling is an approach to interactive narrative where the AI challenge is to tell a story about what the player is doing, with game play providing the ordinary activity that underlies story events. In this preliminary work, we motivate the need for event prediction within this framework, and describe a machine learning approach to the problem. We report results showing how different feature models can be learned and compared in this context, towards automating model selection.

Amplitude modulated atomic force microscopy (AM-AFM), also known as tapping-AFM, has been applied... more Amplitude modulated atomic force microscopy (AM-AFM), also known as tapping-AFM, has been applied to the quantification of second nano-phases in the AA 7075-T651 aluminum alloy (GP-zones, eta’ and eta phases). Specialized image analysis software was used to obtain statistical information from phase contrast AFM images. The method here described drastically reduces the effort required for sample preparation, contrasted with the one demanded by transmission electron microscopy, minimizing sample handling and reducing the likelihood of losing relevant information due to sample manipulation. The experimental results are compared with those reported by other authors using transmission electron microscopy, traditionally used for nanoparticle quantification.

Solid state precipitation is the main mechanism of strengthening in the aluminum alloy AA 7075 [1... more Solid state precipitation is the main mechanism of strengthening in the aluminum alloy AA 7075 [1]. This phenomenon affects the hardness of the material depending on precipitate concentration, size, and distribution. In this work, phase-contrast atomic force microscopy (PC-AFM) was applied to study changes in  and ’ precipitate size and distribution in the various regions generated transversely to the joint made by friction stir welding. The results show the microstructural variations caused by the thermomechanical effect due to the welding process, and are correlated with Vickers hardness measurements performed by microindentation.

Lecture Notes in Computer Science, 2003

In this paper, the obtained results on iCLEF-2002 are presented. This is the first time that we t... more In this paper, the obtained results on iCLEF-2002 are presented. This is the first time that we try to face up the iCLEF task, and we have used a Passage Retrieval approach, specifically our previously developed system called IR-n. This system previously divides the document in fragments or passages, and after that, the similarity of each passage with the query is measured. Finally, the document that contains the most similar passage is returned as the most relevant document. In the interactive document selection task, we have experimented with this system in the following way, the system only shows the most relevant passage of each document instead of the entire document. In this work, the results obtained with this system are presented, where the relevant passages presented to the user have been automatically translated into Spanish by means of Systran. Moreover, the results are compared with Z-Prise system, which is based on the reading of the entire document.

SSRN Electronic Journal, 2019

This research provides evidence on the role of information asymmetry and personal affiliations in... more This research provides evidence on the role of information asymmetry and personal affiliations in housing transactions using a novel dataset that allows observation of detailed information about the property, broker, and seller. Sellers holding a real estate license are found to obtain about 1.6 percent (or $3,200) more for their properties than unlicensed sellers, and sellers personally affiliated to a real estate licensee (e.g., spouses, siblings, parents) also obtain a premium of about the same size, all else equal. There is evidence from appraisal training that knowledge of property valuation further increases the price disparities, while informative public property records reduce price disparities. Agents and personal affiliates appear to use information advantages to time the market and capture capital gains. These new findings provide insights into the behaviors of market participants in asymmetric information environments.

Lecture Notes in Computer Science, 2008

Lecture Notes in Computer Science, 2016

Opportunistic storytelling is an approach to interactive narrative where the AI challenge is to t... more Opportunistic storytelling is an approach to interactive narrative where the AI challenge is to tell a story about what the player is doing, with game play providing the ordinary activity that underlies story events. In this preliminary work, we motivate the need for event prediction within this framework, and describe a machine learning approach to the problem. We report results showing how different feature models can be learned and compared in this context, towards automating model selection.

Amplitude modulated atomic force microscopy (AM-AFM), also known as tapping-AFM, has been applied... more Amplitude modulated atomic force microscopy (AM-AFM), also known as tapping-AFM, has been applied to the quantification of second nano-phases in the AA 7075-T651 aluminum alloy (GP-zones, eta’ and eta phases). Specialized image analysis software was used to obtain statistical information from phase contrast AFM images. The method here described drastically reduces the effort required for sample preparation, contrasted with the one demanded by transmission electron microscopy, minimizing sample handling and reducing the likelihood of losing relevant information due to sample manipulation. The experimental results are compared with those reported by other authors using transmission electron microscopy, traditionally used for nanoparticle quantification.

Lecture Notes in Computer Science, 2006

This paper introduces a novel unstructured P2P system able to adapt its overlay network topology ... more This paper introduces a novel unstructured P2P system able to adapt its overlay network topology to the load conditions. The adaptation is performed by means of a mechanism which is run by the nodes in the network in an autonomous manner using only local information, so no global coordinator is needed. The aim of this adaptation is to build an efficient topology for the resource discovery mechanism performed via random walks. We present the basis of the adaptation mechanism, along with some simulation results obtained under different conditions. These results show that this system is efficient and robust, even in front of directed attacks.

Solid state precipitation is the main mechanism of strengthening in the aluminum alloy AA 7075 [1... more Solid state precipitation is the main mechanism of strengthening in the aluminum alloy AA 7075 [1]. This phenomenon affects the hardness of the material depending on precipitate concentration, size, and distribution. In this work, phase-contrast atomic force microscopy (PC-AFM) was applied to study changes in  and ’ precipitate size and distribution in the various regions generated transversely to the joint made by friction stir welding. The results show the microstructural variations caused by the thermomechanical effect due to the welding process, and are correlated with Vickers hardness measurements performed by microindentation.

Lecture Notes in Computer Science, 2003

In this paper, the obtained results on iCLEF-2002 are presented. This is the first time that we t... more In this paper, the obtained results on iCLEF-2002 are presented. This is the first time that we try to face up the iCLEF task, and we have used a Passage Retrieval approach, specifically our previously developed system called IR-n. This system previously divides the document in fragments or passages, and after that, the similarity of each passage with the query is measured. Finally, the document that contains the most similar passage is returned as the most relevant document. In the interactive document selection task, we have experimented with this system in the following way, the system only shows the most relevant passage of each document instead of the entire document. In this work, the results obtained with this system are presented, where the relevant passages presented to the user have been automatically translated into Spanish by means of Systran. Moreover, the results are compared with Z-Prise system, which is based on the reading of the entire document.

Lecture Notes in Computer Science, 2008

Lecture Notes in Computer Science, 2006

This paper introduces a novel unstructured P2P system able to adapt its overlay network topology ... more This paper introduces a novel unstructured P2P system able to adapt its overlay network topology to the load conditions. The adaptation is performed by means of a mechanism which is run by the nodes in the network in an autonomous manner using only local information, so no global coordinator is needed. The aim of this adaptation is to build an efficient topology for the resource discovery mechanism performed via random walks. We present the basis of the adaptation mechanism, along with some simulation results obtained under different conditions. These results show that this system is efficient and robust, even in front of directed attacks.

Lecture Notes in Computer Science, 2005

Theory of Computing Systems, 2007

In this paper we start the study of generalizing the Adversarial Queueing Theory (aqt) model towa... more In this paper we start the study of generalizing the Adversarial Queueing Theory (aqt) model towards a continuous scenario in which the usually assumed synchronicity of the evolution is not required anymore. We consider a model, named continuous AQT (caqt), in which packets can have arbitrary lengths, and the network links may have different speeds (or bandwidths) and propagation delays. We show that, in such a general model, having bounded queues implies bounded endto-end packet delays and vice versa. From the network point of view, we show that networks with directed acyclic topologies are universally stable, i.e., stable independently of the protocols and the traffic patterns used in it, and that this even holds for traffic patterns that make links to be fully loaded. Concerning packet scheduling protocols, we show that the well-known lis, sis, ftg and nfs protocols remain universally stable in our model. We also show that the caqt model is strictly stronger than the aqt model by presenting scheduling policies that are unstable under the former while they are universally stable under the latter.

Scandinavian Cardiovascular Journal, 1992

Thirty-five patients who had undergone surgery for non-small cell bronchogenic carcinoma with iso... more Thirty-five patients who had undergone surgery for non-small cell bronchogenic carcinoma with isolated involvement of the chest wall were reviewed. The diagnosis was preoperatively suspected in 80% of cases. En-bloc resection of the invaded chest wall was performed in 25 cases and parietal pleurectomy in ten in which the pleura was easily dissectable from the costal plane. Of the eight patients with major complications in the early postoperative period, six, including the two who died perioperatively, had undergone en-block resection. The 5-year actuarial survival rate was 22% overall and 36% in the patients without lymph node involvement. No significant relationship between survival and type of operation or degree of chest wall invasion was found. Isolated involvement of the chest wall by non-small cell bronchogenic carcinoma does not necessarily contraindicate surgery with curative intent. Parietal pleurectomy is valid in selected cases. Long-term survival depends basically on node involvement.

Proceedings of the National Academy of Sciences, 1977

The ability of three cultured mouse tumor lines to stimulate a cytotoxic response in 5-day cultur... more The ability of three cultured mouse tumor lines to stimulate a cytotoxic response in 5-day cultures of allogeneic lymph node cells was studied with a 51Cr release assay. Two lines of mesenchymal origin, P815 and EL-4, were found to be highly stimulatory, whereas the third cell line, CaD2, a mammary gland epithelial tumor, did not stimulate over a wide range of cell concentration. CaD2 cells were shown to contain major antigens similar to those of P815 cells by the specific lysis of both cells by lymphocytes activated to H-2d-bearing peritoneal cells.UV-irradiated P815-cells, like gamma-irradiated CaD2 cells, did not stimulate a cytotoxic response, but both cell lines were found to stimulate a full and specific response to allogeneic lymph node cells if these mixed cultures were supplemented with a supernatant harvested from concanavalin A-stimulated spleen cells.