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Improvisation and trust in human/autonomy teams: a task-based perspective
No full textAugust 2024School of EngineeringThis dissertation explores and investigates the interplay between processes of improvisation and trust within collectives composed of human and synthetic agents. Observations and insights from various settings, particularly but not exclusively in the arts, suggest a close relationship between improvisation and trust. On the one hand, improvisation entails creativity (the production of novel actions) under time constraint. On the other, trust can be both an enabler and a by-product of improvisation, as–through shared experiences–team members understand each other’s capabilities, even under highly non-routine conditions. With the potential introduction of artificially intelligent (AI) (or synthetic) team members to these types of task, questions arise surrounding the conditions under which human/AI team members can (or should) improvise and build trust. Prior research on improvisation in human groups outside the domain of music has overwhelmingly been informed by opportunistic observation in the field. In contrast, this dissertation begins to pry apart the complex processes of improvisation and trust through a combined program of theory-building and human-in-the-loop experimentation. The central question this work seeks to address is “How do task-related constraints and goals determine the extent to which the behavior of human and human-AI collectives is planned or improvised and affect trust?” This research first establishes the theoretical basis that associates task constraints with the response to these constraints in human collectives (which for simplicity we refer to as groups). To do this an analysis and synthesis of prior research is performed to yield theoretical models that suggest how task-related factors —time constraint, locus of control,and workflow— shape how behavioral responses range from planned to improvised in Chapter 3. The second part of the research further expands these theoretical models with the inclusion of trust, represented with three aspects (competence, predictability and integrity), among members of human-AI groups in Chapter 4. The previous parts of the research yield a task-centric analysis of prior literature on improvisation and related areas, while also providing a set of research questions and propositions for further testing in controlled settings. The third and last part of the research presents the design and development of an experiment in order to test propositions regarding the processes of human improvisation and trust in human/AI groups and changes in the task environment. The study and results are presented in Chapter 5. Conclusions and proposed work of the overall thesis are presented in Chapter 6. This work has three contributions. The first contribution is the development of a theoretical basis to associate the design of task-related constraints with (improvised) behavioral responses by human or human-AI groups. The second contribution is a parallel exploration of the aspects of trust and the behavioral measurements developed for these aspects in a human-AI group setting. The third contribution is the development of an experimental paradigm that allowed the evaluation of behavioral measurements of the aspects of trust for a human-AI team in a creative task.Ph
Redox-coupled spin crossover in cobalt coordination complexes
No full textMay 2024School of ScienceCobalt coordination compounds consisting of a single five-coordinate cobalt(III) salen (CoIIISln+) complex and two cobalt β-diketonate complex [(Co(acac)2((CC)2bpy)] and [Co(dbm)2((CC)2bpy)] were synthesized. The redox-coupled spin crossover behavior of these complexes were then studied using electrochemical and spectroscopic methods. CoIIISln+ is high-spin in both its +2 and +3 oxidation states, but its remaining open coordination site allows for exogenous ligands to bind to the +3 oxidation state inducing a high-spin to low-spin transition. This transition is accompanied by changes in color and induces a drastic electrochemical shift. The changes in electrochemistry correlate nicely to the basicity of the ligand as measured by gas phase basicity. For pyridine ligands the shift also correlates to the Hammett parameter of the para substituent. This complex is a notable example of a cobalt complex which undergoes both redox-coupled spin crossover and coordination-induced spin crossover. In pursuit of a better understanding of these interactions a review of similar coordination-induced spin crossover systems was performed. The two β-diketonates also undergo redox-coupled spin crossover. The +2 oxidation states are both high-spin, but upon oxidation a rearrangement takes place that results in a low-spin cobalt(III) metal center. Like CoIIISln+, the high- and low-spin states of [Co(acac)2((CC)2bpy)] and [Co(dbm)2((CC)2bpy)] have very different spectral properties. Attempts to fashion electrochromic multilayers out of these complexes were unsuccessful. These failed experiments provided insights into the synthetic modifications needed for related complexes to be made into functional multilayers and multiple future directions for this research is discussed.Ph
The role of glycoxidation on bone mineralization and matrix quality
No full textMay 2024School of EngineeringType 2 diabetes (T2D) and obesity are prevalent conditions associated with heightened fracture risk despite patients exhibiting normal or elevated bone mineral density (BMD). BMD is a routinely used measurement that predicts fracture risk in osteoporosis, so the inability for BMD to accurately capture fracture risk in T2D and obesity suggests that the quality of bone is impaired rather than its quantity in these conditions. Thus, much effort has been directed to determine how bone quality, which contributes to bone strength independently of BMD, is perturbed in T2D and obesity. Chronic, low-grade inflammation is a common feature of T2D and obesity that subsequently promotes glycoxidation, a simultaneous glycation-oxidative stress process that generates advanced glycation end-products (AGEs) which can accumulate on proteins like collagen. Yet, little is known on the extent to which glycoxidation perturbs the extracellular matrix quality of bone. To this end, this research project aims to determine the role of glycoxidation on bone mineral and matrix quality, two nanoscale properties that contribute to bone’s fracture resistance. Inflammation, and consequently glycoxidation, is mediated by the receptor for advanced glycation end-products (RAGE). To investigate how glycoxidation impacts the matrix quality of bone, this project utilized an in vivo approach where wildtype and RAGE knockout mice were provided high-fat diet to induce obesity and inflammation. Results show that obesity induces glycoxidative AGE accrual in bone and was associated to altered mineral and matrix quality, while RAGE ablation ameliorated and preserved aspects of the bone matrix. The findings suggest that glycoxidation in obesity, via accrual of certain AGEs, is a process that can perturb the extracellular matrix of bone, working to change its quality and fracture resistance by extension.
To expand on the in vivo findings, an in vitro study was implemented where human bone was modified through the accrual of carboxymethyl-lysine (CML) and crosslinking AGEs and were later mineralized to elucidate the mechanism linking glycoxidation to altered bone mineralization and ultrastructural composition. Findings from this study demonstrated that AGE accumulation altered the molecular dynamics of collagen and mineral, and enhanced mineralization. These results augment the notion that glycoxidation impacts the quality of bone while also providing evidence of the nanoscale mechanism by which glycoxidation, via AGE accrual, perturbs the principal components of the bone matrix.
The impact of glycoxidation on citrate-mediated mineralization was investigated to elucidate another pathway by which oxidative stress can impair bone quality. It was discovered that glycoxidation interferes with citrate’s capacity to regulate mineralization, most likely by impairing the adsorption of citrate from solution into the organic network. Since citrate content, which is reflective of cellular metabolism, is influenced by oxidative stress, these findings provide novel evidence that glycoxidation may impair bone quality by altering the dynamics of citrate-mediated mineralization.
Finally, a mechanism explaining residual stress in bone mineral was explored to identify a pathway by which glycoxidation could impair the mechanical function of mineral through alterations to energy dissipation. It was discovered that epitaxial growth between unique crystals occurred in native bone, and organic matrix proteins were crucial for this type of growth modality. A model was designed to estimate the amount of stress caused by epitaxy in bone mineral, which can be further refined to elucidate how glycoxidation impairs bone’s mechanical properties by altering the residual stress state in the bone matrix.
Collectively, this research project demonstrates that the glycoxidation process can both directly and indirectly affect bone quality by altering the growth of mineral. This discovery greatly builds upon the established notion that oxidative stress in conditions like T2D and obesity impair bone quality by affecting the organic phase, and clearly demonstrates that the mineral phase and mineralization process can also be modified by oxidative stress products in the bone matrix. The findings from this work also provides a new way to better comprehend the reason behind the high fracture prevalence seen in T2D and obesity, which is critical for the development of diagnostic and preventative measures needed to mitigate fracture in these at-risk populations.Ph
In-situ tem study of filament evolution in metal filament-based resistive switching devices
No full textDecember 2023The growing requirement of higher speed and lower energy computation for ever increasing data workloads have impressed the need for development of neuromorphic computing hardware like artificial synapses that exhibit fast, low power, and reliable switching into multiple resistance states. A good potential candidate for these artificial synapses is metal filament based resistive switching devices which switch between different resistance states via modulation of metallic filament(s) present in the insulator of its metal/insulator/metal structure. However, the observed variability in the state resistance, which is linked to the stochastic nature of the filament evolution process, poses a challenge to its artificial synapse application. Therefore, it is important to fundamentally understand the filament evolution process in these devices and determine the role of factors that influence it. Due to the dynamic nature of the nanoscale filament evolution process during device operation, in-situ transmission electron microscope (TEM) electrical testing can play a big role in the development of the understanding about the filament evolution process. The process broadly consists of three sub processes: i) Redox reactions at the electrodes to generate metal cations, ii) Metal cation injection into the insulator and transport under high electric field, and iii) Reduction of metal cations to form precipitates that grow into a filament spanning the insulator between the electrodes. In this thesis the effect of four different factors: electrode material, testing temperature, TEM imaging current density and ambient vacuum on these sub processes and how it affected the filament evolution is explored.
Lateral metal/SiO2(~ 100 nm)/metal devices (metal: Cu, Ag, Co) compatible to in-situ TEM electrical testing in an electrical biasing and heating holder were designed and fabricated. It was found by in-situ TEM electrical testing of Cu/SiO2/Cu devices at room temperature, that the metal filament initial forms near the anode and grows as a collection of discontinuous precipitates towards the cathode. The filament was confirmed to be in the bulk of SiO2 film rather than the exposed surface. Image processing methods were developed to quantify the information about filament evolution from the contrast evolution in the in-situ TEM data. This was used to compare the effect of different factors on the filament evolution process.
It was found that for Cu/SiO2/Cu devices, the metal filament evolution occurred in air or in TEM vacuum with imaging electron irradiation but not in TEM vacuum alone. It was also shown that the imaging electron current density had a positive correlation with the amount of Cu injected into SiO2. A mechanism for filament evolution in a vacuum ambient for SiO2 based metal filament resistive switching devices was proposed wherein Cu oxidation at the anode is enabled by the reduction of oxygen vacancies (V_O^(2+)+2e^-→ V_O) generated in SiO2 by high energy imaging electrons, at the cathode.
Filament formation in Cu/SiO2/Cu devices for 3 temperatures (298 K, 498 K and 698 K) was investigated and found that the filament in all three cases originates from the anode. Increase in temperature results in a larger dispersion of sizes which was explained by increase in redox reaction rate at the electrodes with temperature. It was concluded that the increase in temperature influences the filament evolution primarily through increase in redox reaction rates at the electrodes with lesser impact on ionic mobility.
The effect of change of electrode material on the filament evolution process was also studied by performing in-situ TEM electrical testing of lateral metal/SiO2/metal devices with Cu, Ag, and Co electrodes at 298 K. Qualitatively, the filament evolution process was similar in all three metals, but the amount of metal injected into the SiO2 followed the trend of the reduction potential (Ag>Cu>Co) of the respective ions. This was deduced from the largest amount of total projected area fraction of SiO2 covered by metal precipitates for Ag, followed by Cu and then Co.
In summary, we studied the role of 4 different factors on the filament evolution in metal filament resistive switching devices. We found that filament evolution for in-situ TEM conditions with ambient vacuum and electron irradiation is different than that for air ambient. We proposed, that a vacancy reduction based cathodic reaction for in-situ TEM replaces the standard water reduction cathodic reaction in the air ambient. We also showed that the precipitates comprising the filament become larger with decreasing reduction potential of the electrode metal or by increase in temperature during filament formation, while the filament originates near anode for all cases. This led to the conclusion that the redox processes dominate filament formation in SiO2.Ph
Structural control of photo-curable acrylic resins using photopolymerization-induced phase separation
No full textDecember 2023School of ScienceHeterogeneous thermosetting polymeric material development is of growing interest in the field of material science due to the belief that the development of unique microstructures can provide benefits to the resulting material properties. Advances in these properties have already been explored by the addition of nanoparticles or elastomeric particles into epoxy-based polymer networks. Additional methods of heterogeneous thermoset fabrication include the use of polymer blends, block copolymers, and polymerization-induced phase separation (PIPS). Due to the minimal restrictions on material processing and development, light-initiated PIPS (photo-PIPS) is used in this thesis to fabricate various heterogeneous thermosetting materials through use of phase separation. Photo-PIPS can yield various shapes and sizes of the phase-separated subdomains by controlling multiple parameters including resin composition, phase-separating agent size and concentration, and light intensity. However, the details of the effect of these parameters on the process and the associated mechanisms which govern network evolution are not entirely understood. In the past, studies have been performed to alter the size and concentration of both polymer additives and nanoparticles to visualize the effects on the subdomains that develop. Few additional studies have also been performed on the light intensity effect. In these studies, while the apparent changes to the subdomains are seen by varying the respective parameters, the mechanisms which control the resulting sizes and shapes are still undetermined. Developing an understanding of these governing mechanisms which control network evolution during the phase separation process can help to better alter the extent of phase separation that can occur within a thermosetting network. This in turn, can allow for fine tuning of the material properties and enable the production of materials suited for various applications such as polymer membranes, polymer composites, polymer-dispersed liquid crystals (PDLCs), and the various applications available with stereolithography (SLA) 3D printing.
In Chapter 1, an introduction to the creation of heterogeneous materials and more specifically, photo-PIPS is provided, including a short review of the literature pertaining to photo-PIPS which discusses how various microstructures have been obtained. Challenges and potential applications of photo-PIPS are also discussed. A summary of the various parameters which can be altered to adjust the material properties of a thermosetting network is also given. An introduction to the studies presented in the subsequent chapters of the thesis is provided.
In Chapter 2, the mechanisms governing network evolution during the photo-PIPS process are determined through use of intermittent light irradiation applied after a period of continuous irradiation to probe network formation at various stages. Specifically, light transmittance experiments and SEM imaging are used to detect the extent and thus, evolution of phase separation. Real-time FTIR is used to examine the impact of intermittent probing on network evolution and profilometry is used to detect network shrinkage. From this chapter, it is learned that phase separation, photoinitiator consumption, and microstructural refinement are the governing mechanisms of network evolution during photo-PIPS.
In Chapter 3, photo-PIPS is implemented into two photo-curable resin systems—one with a stiff crosslinking monomer and one with a soft crosslinking monomer—to determine the effect of this parameter on the extent of phase separation and resulting mechanical properties. Light transmittance, SEM, SWAXS, and DMA are all used to verify the extent of phase separation present. It is also indicated through these experiments that there is a dependence on the extent of phase separation with polymer additive molecular weight in both resin systems, which agrees with the literature. Light intensity effects are studied and their results are also in agreement with the literature. Real-time FTIR confirms the kinetics of photopolymerization in both systems and is compared to the kinetics of phase separation provided by light transmittance experiments. Lastly, mechanical property testing is performed to determine the effects of the rigidity of the crosslinking monomer and also of liquid versus solid, linear-chained phase-separated polymer additive on the material properties. The work here provides an understanding on the parameters which can alter the extent of phase separation including polymer additive chemistry and molecular weight, light intensity, and crosslinking monomer rigidity.
In Chapter 4, a robust polymer network is developed and used for implementation of photo-PIPS using two different polymer additives: PPG and PDMS, to create two different resin systems and visualize the effects on the material properties. Acrylic-based monomers are photopolymerized to develop the polymer network and epoxy-based monomers within the network are crosslinked during thermal treatment after photopolymerization to produce increased material stiffness and strength. PPG is implemented as the phase-separating agent and the extent of phase separation is monitored via transmittance and SEM, showing the same trend in polymer additive molecular weight as the resin systems of Chapter 3. Mechanical property data show a reduction in stiffness, strength, and elongation due to the liquid nature of PPG at room temperature. In the case of the PDMS polymer additive, due to the phase-separating nature of Epoxy-PDMS and non-phase-separating nature of OH-PDMS, mixtures of OH-PDMS and Epoxy-PDMS of various molar ratios are used to alter the extent of phase separation and fine tune the amount of crosslinking that occurs within the subdomains. Transmittance, SEM, and DMA are used to validate the extent of phase separation and real-time FTIR is used to compare the photopolymerization kinetics with the phase separation kinetics determined from transmittance. It is found that minimal phase separation provides sufficient crosslinking within the subdomains to yield an increase in material ductility and creep resistance, while only slightly reducing the stiffness and strength.
Chapter 5 provides conclusionary statements regarding each chapter and their contribution to the current understanding of the photo-PIPS process and the methods that can be used to alter the resulting microstructure and material properties. As a whole, these studies offer insight into the network evolution during photo-PIPS as well as the factors that impact the resulting material such as polymer additive molecular weight and concentration, light intensity, resin composition, and monomer chemistries. It is suggested by these studies that photo-PIPS can provide a vast range of material properties and extents of phase separation, proving to have uses in numerous potential applications. A list of possible future extensions of the present work is provided in closure.Ph
Integrating light-based therapies and diagnostic tools for mild cognitive impairment: effects on neuroinflammation, amyloid beta, and alertness
No full textJuly 2024School of ScienceAlzheimer's disease (AD) presents a significant public health challenge, with its prevalence expected to almost double in the next 25 years. Despite therapeutic advancements, mortality rates continue to rise, highlighting the need for effective interventions. Building on previous research demonstrating the efficacy of 40 Hz rhythmic light (RL) in clearing Aβ aggregates in AD mouse models, this aim of the dissertation explores the effects of varying exposure durations and light levels on neuroinflammation and Aβ42/40 ratios. Increasing exposure durations reduced IL-1β concentrations, while light levels had no significant impact on inflammatory markers. However, neither increased exposure durations nor light levels of 40 Hz RL decreased Aβ42/40 ratios, suggesting refinements are needed in RL administration for AD.Although light level and duration did not improve efficacy of RL on AD model mice, it is important to investigate other variables or effects of light. This aim of the dissertation explores the potential benefits of specific lighting schemes to induce alertness in environments such as hospitals and naval ships. To determine the most efficient wavelength for inducing alertness, nine different (quasi-)monochromatic stimuli were tested on healthy individuals. Electroencephalography (EEG), Go/NoGo (GNG) performance tests, and the Karolinska Sleepiness Scale (KSS) were used to measure subjective sleepiness and cognitive function. Findings indicated that 5 lux and 75 lux improved subjective sleepiness, but that different wavelengths did not impact subjective sleepiness. Longer wavelengths, such as orange and amber, stimulated more whole brain activity according to EEG.
Additionally, it is imperative to establish baseline EEG patterns in those with mild cognitive impairment (MCI) – a transitional state between cognitively healthy and AD- compared to healthy controls (HCs) before implementing lighting therapies. This aim of the dissertation utilizes measures of functional connectivity (FC) and global field power (GFP) from EEG recordings to distinguish patterns of brain activity among various cohorts. Comparative analyses were conducted during rest among young healthy controls (YHC), old healthy controls (OHC), and individuals with MCI to identify potential biomarkers for cognitive decline in MCI. Results indicated significantly higher FC within the Central Executive Network (CEN), Default Mode Network (DMN), and Salience Network (SN) among MCI participants compared to both control groups. Additionally, MCI participants exhibited notably reduced GFP in the DMN compared to controls. A significant negative correlation was found between FC in the SN and sleep quality, as measured by the Pittsburgh Sleep Quality Index (PSQI). These findings suggest that FC and GFP metrics have potential clinical utility as early diagnostic indicators for cognitive decline in MCI.Ph
The world digital library and the politics and promises of knowledge societies
No full textAugust 2024School of Humanities, Arts, and Social SciencesThe World Digital Library (WDL) was a joint project by UNESCO and the LOC aimed at creating a unitary digital repository of the ‘world’s most important cultural treasures’ through a cooperative global undertaking. The stated objective of the WDL was to contribute to UNESCO’s global policy agenda of building of inclusive knowledge societies. This agenda, as articulated within UNESCO’s 2005 World Report, Towards Knowledge Societies, sought to enhance international cooperation in the digital information landscape, increase the variety and volume of cultural content and heritage available online, and promote intercultural understanding. Situating the emergence of the WDL in the context of UNESCO’s Knowledge Societies policy agenda, this dissertation approaches the WDL as a site for investigating the practicalities, politics, and power dynamics implicated in international cooperation in digital cultural projects. Accordingly, this dissertation offers an infrastructural analysis and history of the WDL project itself and, simultaneously, positions the WDL as a case study of the implications of UNESCO’s Knowledge Societies agenda. I ultimately argue that UNESCO’s calls for enhanced international cooperation in digital cultural/heritage projects, bereft of direct intergovernmental oversight and de jure standard-setting, serves to reproduce the de facto hegemony of dominant ways of organizing, classifying, and presenting cultural heritage online. To illustrate this, I explicate and historicize the power dynamics that shaped the WDL’s efforts to actualize the objectives and the policy recommendations of UNESCO’s Knowledge Societies agenda.
Drawing on oral testimonies from key actors and participants in the WDL project, I show that, despite having been proposed and framed as a shared global undertaking, the LOC ultimately took a dominant position in content selection and processing, thereby wielding hegemonic control over the curation and presentation of the WDL and its international collections. Because of this untoward influence of the LOC, the WDL not only failed to foster international cooperation but, moreover, reproduced the LOC’s ways of knowing and constructing ‘the Other,’ falling short of actualizing its stated objective of fostering intercultural dialogue and understanding. Through this analysis, I highlight the power-dynamics implicated in and trace the conditions of impossibility for fostering international cooperation in the project.
Approaching this topic through a history of the present, I trace the historical arrangements and conditions upon which the power-dynamics embedded in the design and development of the WDL have been built and made possible. I argue that, in addition to socio-economic and structural inequities, the conditions of impossibility for international cooperation have been sustained and enabled through the diminishing role and influence that international institutions hold in shaping norms for the international library and bibliographic community. Furthermore, I show that the decreased influence of international institutions has been accompanied by the de facto hegemony of US and US industry-based standards for organizing and classifying information in both digital and physical libraries worldwide. In doing so, I highlight the somewhat paradoxical relationship between decentralization and hegemony and position the WDL as a case study of the broader socio-cultural and epistemic consequences of this relationship on the construction of the ‘digital cultural record’.Ph
Uncovering Agendas: A Novel French & English Dataset for Agenda Detection on Social Media
No full textThe behavior and decision making of groups or communities can be dramatically influenced by individuals pushing particular agendas, e.g., to promote or disparage a person or an activity, to call for action, etc.. In the examination of online influence campaigns, particularly those related to important political and social events, scholars often concentrate on identifying the sources responsible for setting and controlling the agenda (e.g., public media). In this article we present a methodology for detecting specific instances of agenda control through social media where annotated data is limited or non-existent. By using a modest corpus of Twitter messages centered on the 2022 French Presidential Elections, we carry out a comprehensive evaluation of various approaches and techniques that can be applied to this problem. Our findings demonstrate that by treating the task as a textual entailment problem, it is possible to overcome the requirement for a large annotated training dataset
ChatBS: An Exploratory Sandbox for Bridging Large Language Models with the Open Web
No full textThe recent widespread public availability of generative large language models (LLMs) has drawn much attention from the academic community to run experiments in order to learn more about their strengths and drawbacks. From prompt engineering and fine-tuning to fact-checking and task-solving, researchers have pursued several approaches to try to take advantage of these tools. As some of the most powerful LLMs are ``closed'' and only accessible through web APIs with prior authorization, combining LLMs with the open web is still a challenge. In this evolving landscape, tools that can facilitate the exploration of the capabilities and limitations of LLMs are desirable, especially when connecting with traditional web features such as search and structured data. This article presents ChatBS, a web-based exploratory sandbox for LLMs, working as a front-end for prompting LLMs with user inputs. It provides features such as entity resolution from open knowledge graphs, web search using LLM outputs, as well as popular prompting techniques (e.g. multiple submissions, ``step-by-step''). ChatBS has been extensively used in Rensselaer Polytechnic Institute's Data INCITE courses and research, serving as key tool for utilizing LLMs outputs at scale in these contexts
On the development of non-invasive diagnosis tools with optical wavefront shaping
No full textMay 2024School of EngineeringThe use of light has reformed our approaches to diagnose or treat diseases, and transformed our understanding of physiological processes. Many of today’s optical technologies such as fluorescence microscopy, optogenetics, or photodynamic therapy rely on the precise delivery of light to or from target cells or tissues. However, the scattering of light as it penetrates through skin or tissue poses a significant challenge, restricting the performance of these techniques, limiting imaging depth, and requiring invasive procedures. A plausible solution to this problem lies in the ability to control the scattered light in a desired manner, which has been made feasible by wavefront shaping methods. Wavefront Shaping methods hold the potential to overcome the limitations of these optical technologies by increasing imaging depth, enhancing signal and sensitivity.Wavefront shaping methods can be applied to focus light through scattering media at a predefined target. However, in order to utilize the full potential of the biological applications such as deep tissue fluorescence imaging, we need to extend beyond generating a single focus. We have to consider signal extraction from targets hidden behind scattering media, generation of multiple focus points, and simultaneous enhancement of signals emitted by multiple fluorescent targets.
Here, we present an optical wavefront shaping method that allows enhancement of ini- tially weak signal emitted by sources (i.e., fluorescent particles) hidden behind a scattering medium. We propose a method that combines traditional feedback based wavefront shaping method together with a switch function and demonstrates utilization of two different sig- nals for shaping the incident wavefront. By taking advantage of the instantaneous changes induced by the modulation of the incident light, the hidden targets are located at first. A switch function introduced in the algorithm then advances optimization of the hidden sig- nal. Additionally, we present a simple, easy to implement scoring based genetic algorithm (SBGA) that can obtain multiple objectives simultaneously. Each possible solution acquires scores based on its capability to optimize individual objectives and the scores are combined to identify the optimal solution. We experimentally demonstrate our method by generat- ing multiple focus points, controlling intensity distribution, and preventing irradiation in neighboring region. We further extend our work to apply multiple image quality metrics with SBGA and devise a method that optimizes signals from multiple fluorescent targets at a time. By applying a simple image analysis technique, thresholding, the image is ini- tially segmented into background and object pixels. Two well known image quality metrics, entropy and mean intensity of the thresholded image are then employed as the objective functions to perform optimization. We demonstrate that combination of this method with Bessel-Gaussian beam (BG) yields higher enhancement compared to Gaussian beam. All of these methods can potentially be applied to develop noninvasive or minimally invasive optical tools for medical diagnosis or treatment.Ph