Digital Card Research Articles

Design of IoT-based monitoring system for temperature and dissolved oxygen levels in catfish aquaculture pond water

<span>One of the fish in Indonesian waters that has been successfully bred and cultivated is the catfish (Pangasius sp.). In catfish farming, there are several water quality factors that need to be considered, such as temperature and dissolved oxygen levels. Based on the existing description, it is very important to pay attention to the water quality of aquaculture ponds, especially temperature and dissolved oxygen levels for fish survival. This study aims to create an internet of things (IoT) based monitoring system for temperature and dissolved oxygen levels in catfish aquaculture pond water based on NodeMCU ESP8266. Monitoring system is using SEN0237 gravity analog dissolved oxygen sensor, DS18B20 sensor module, NodeMCU ESP8266, 20×4-character liquid-crystal display (LCD), micro secure digital (SD) card module, internet modem. Data from measurements of temperature and dissolved oxygen levels are stored online in the Adafruit.io database in the .csv format and on a micro secure digital (SD) card in the device in the .txt format. The lowest value of dissolved oxygen levels and temperature are 3.4 mg/L or 3.4 ppm and a temperature of 27.9 °C, respectively. Meanwhile, the highest value of dissolved oxygen levels and temperature are 4.6 mg/L or 4.6 ppm and temperature of 30.9 °C, respectively.</span>

An interdisciplinary approach: Exploring the five dimensions of the tools deployed by EUVABECO

Abstract To effectively address the complexities of vaccination across the EU, EUVABECO’s 14 partners are implementing a comprehensive, interdisciplinary approach. Twelve pilot projects will be implemented from September 2024 to August 2025 in six MS (BE, DE, EL, LV, LU, PL, PT). These pilots will test innovative tools across five domains-medical, social, industrial, modelling and forecasting, and digital-to optimize vaccination outcomes: Medical/Clinical Tool: A decision support system that aids patients and healthcare professionals by providing current, evidence-based information tailored to individuals, thereby facilitating informed vaccination decisions. Social Tool: Data linkage on an individual level, to enhance the targeting and monitoring of vaccine campaigns, and ensuring equitable access to vaccines, especially for vulnerable populations. Industrial Tool: An electronic vaccine leaflet that boosts the flexibility and responsiveness of vaccine distribution by offering dynamic, real-time information in local languages to both healthcare providers and patients - regardless of the source and point of use of the vaccine. Modelling and Forecasting Tool: A disease simulator that models infection dynamics and evaluates the impact of public health interventions, crucial for strategic planning and resource allocation. Digital Tool: A citizen-held digital vaccination card that enables individuals to maintain a comprehensive, accessible record of their own vaccination histories, enhancing continuity of care across borders.

Embracing the Digital Network: How Net-Entrepreneurs Acquire Online Social Capital?—A Mixed Empirical Study Based on SEM-PLS and fsQCA

Online social capital is a determinant of success for net-entrepreneurs. However, there has been limited research on how net-entrepreneurs acquire online social capital through social media. Therefore, this study aims to explore whether different digital behaviors of net-entrepreneurs lead to differences in acquiring online social capital. We conducted empirical tests using partial least square structural equation method and fuzzy-set qualitative comparative analysis (fsQCA) based on survey data from 306 Chinese agricultural net-entrepreneurs. The results revealed that digital business card (profile and state self-disclosure) significantly influences bridging online social capital (BRSC) and bonding online social capital (BOSC). Certain subcomponents of digital information and digital communication serve as significant predictors of online social capital. Furthermore, the acquisition of BRSC has three distinct configurational conditions, while BOSC has four. This study provides valuable insights for net-entrepreneurs on utilizing different digital behaviors to acquire online social capital effectively.

Microfinance, Financial Inclusion and Economic Welfare in Africa: A Panel Investigation

This study explores the relationship between microfinance, financial inclusion, and economic welfare in a sample of 23 African countries for the period of 2004 to 2023 using annual time series data. We measured microfinance with the number of Branches of Microfinance banks, Microfinance Borrowers, Microfinance outstanding deposits, Microfinance outstanding loans; financial inclusion number of registered mobile money accounts per 1,000 adults; the number of mobile money agent outlets par 1,000 adults; and digital card ownership; governance and institutional quality with Rule of law, regulatory quality, and government effectiveness; and economic welfare with household consumption; while we controlled for the inflation rate, interest rate and exchange rate. These variables were estimated using Panel Least Squares, Fully Modified OLS (FMOLS), Dynamic OLS (DOLS), and Panel Autoregressive Distributed Lag (ARDL) estimation techniques. The result of the cointegration revealed that cointegration exists between the variables of the model. Findings from the aforesaid estimation techniques show that there is the existence of long-run relationships between microfinance, financial inclusion, and economic welfare since the coefficients of the microfinance and financial inclusion variables are statistically significant. The coefficients of the error correction terms which measure the effects of the short-run dynamics of the model suggest that the speeds of adjustment from the long run to the short run in the models would be 76%, 61%, 83%, 67%, 68%, 34%, and 80% respectively for all the specified models. Following the findings of the study, conclusions were drawn and the study suggests that microfinance institutions should adapt to the digitization of their products and services for wider coverage on one hand; the government should provide digital financial amenities to create a fertile ground for micro-financial institutions to rely on to maximize the welfare of the economy.

QRGB+: Advanced QR Code Generator with RGB Color Method in Python to Expand Data Capacity

The present work entitled QRGB, consists of the development of an application in Python for the generation of QR codes using the additive color generation (RGB) method. This innovative method allows increasing the density of information stored in QR codes by using three color layers (red, green and blue), each representing a different set of data. QRGB offers an efficient and secure solution for storing and transmitting large amounts of information in limited spaces, significantly improving the capabilities of traditional black and white QR codes. By using three layers of colors, QRGB codes can store up to three times more information in the same space. This technique not only increases storage capacity but also improves information security, making it difficult to forge or manipulate the code. The overlay of multiple data layers allows redundancy to be implemented, increasing the robustness of the code against damage or reading errors. QRGBs are especially useful in applications that require the transmission of large amounts of data in limited spaces, such as in the packaging industry, digital business cards, and interactive advertising. Additionally, they have great potential in areas such as document and banknote security, where the authenticity and integrity of information are crucial. These points provide a solid foundation for understanding the innovation and advantages of colored QR codes (QRGB) compared to traditional QR codes, highlighting their applicability and potential in various sectors. This article presents a novel method for encoding and decoding information using a QRGB code, which involves the generation of three independent QR codes and their superimposition according to the additive color system (RGB). The research highlights the challenges encountered during the encoding and decoding processes due to the lack of specific libraries in Python, which required the creation of a custom solution using open source tools. The implementation takes advantage of Python and its libraries: qrcode[pil] to generate QR codes with the Pillow dependency for image manipulation, Pillow to open, manipulate and save different image formats, and opencv-python to perform tasks such as image processing and object detection. Despite facing issues with color mixing and accurate information retrieval, the proposed method demonstrates a significant increase in data density within a single QR code. Future work will focus on optimizing the algorithm and exploring potential applications in data security and high-density information storage. This Python script is designed to generate and decode QR codes with a logo overlay using a graphical user interface (GUI) built with Tkinter. The script combines several functionalities, such as creating QR codes, overlaying a logo, combining QR images of different colors, and manually decoding combined QR codes.

Design of an Embedded Test Bench for Organic Photovoltaic Module Testing

In this article, a multipurpose embedded system for testing organic photovoltaic modules is presented. It is designed to include all the features for real-time monitoring, data acquisition, and power conversion based on a Ćuk converter, providing useful data for scientific investigation of the outdoor operation of organic photovoltaic modules. The embedded system allows both the scan of the I–V curve and the continuous operation of the organic photovoltaic module, such as at its maximum power. Voltage and current at the terminals of the organic photovoltaic module under test and up to four temperatures are continuously measured and stored on a Secure Digital card. The communication interface allows the embedded system to connect with other instruments, such as irradiance sensors, with digital serial output. The embedded system is designed both for laboratory and in-the-field use: it can be powered either by the AC electrical grid or a battery, which can also operate as a backup battery. Galvanic isolation divides the embedded system into the field-side and the logic-side functional sections, providing improved noise immunity and safe operation. The main power distribution system within the embedded system is a +9 V bus; ultra-low-noise linear low dropout regulators provide the +3.3 V and +5 V regulated voltages to supply the analog and digital circuits within the logic-side section, and a flyback converter supplies the field-side section of the board. The proposed embedded solution is validated using an experimental setup built at SolarTechLab, Politecnico di Milano. The experimental results report the feasibility of the proposed embedded system.

Hybrid PVP/Battery/Fuel Cell Wireless Charging Stations Using High-Frequency Optimized Inverter Technology for Electric Vehicles

The design and integration of intelligent energy management systems in hybrid electric vehicle (EV) charging stations, leveraging industry 4.0 and renewable energy sources, is crucial for advancing sustainability, efficiency, and technological development. The innovative hybrid EV charging station described in this study uses a combination of fuel cells, batteries, and solar panels that run at 14 amps a piece at 240 volts. The system consists of five essential components that work together to transfer power wirelessly: an EV battery bank, a boost converter, an HF inverter, transfer coils, and a power supply. Two crucial phases make up the optimization process. In phase 1, the boost converter’s maximum power point is tracked and optimized to generate the most power possible by varying the duty cycle between 10% and 90%. In phase 2, the HF uses a class ϕ2 inverter at 30 MHz to synchronize with the resonant frequency of wireless power transfer coils. Zero-voltage switching is used by a digital signal processor card to carry out control for effective operations. By utilizing hybrid sources to optimize power transmission, this design improves the sustainability of EV charging options.

AI-deation: When the Teacher is a Transformer in Role-Playing to create Privacy Decision Serious Games

Understanding the synergistic potential of human collaboration with artificial intelligence (AI) in creative endeavours, such as ideating Serious Game (SG) concepts, is of vital interest in our era of digital transformation. This study probes two pivotal questions: First, how does the incorporation of a GPT-4 transformer AI, assuming the role of a teacher, influence support for student teams during the ideation and balancing of SG concepts? Second, what are the students' perceptions of AI integration when co-designing these concepts with an AI in the educator role? In a between-group research design, two distinct groups engaged in a collaborative role-playing activity with digital role-specific cards and a visualised board to ideate and balance Serious Games addressing privacy decision-making. The first group, engaging in a local setting, collaborated with an AI that played the teacher role. In contrast, the second group played the co-ideation activity in a remote setting, with a human playing the role of the teacher. The findings indicate that generative AI can successfully be sourced to play the teacher role in a collaborative role-playing activity. Crucially, the timing of AI intervention thereby emerged as an essential factor that can impair creative support. Scheduled AI interventions can offer fresh insights but may not align with immediate team needs. The insights underscore the requirement to determine the most effective timing for AI intervention in human-AI co-playing ideation sessions to foster the full potential of an AI filling a role in a collaborative design process. Implications synthesised from the analytical findings and practical insights on AI-suggested design propositions/conflicts are discussed conclusively.

Enhancing Road Safety Vehicle Black Box with Advanced Accident Detection and Alert System

Autonomous vehicles want reliable and strong sensor suites and alert systems. This paper discusses the composition and performance of a sophisticated monitoring and alert system for automobile vehicle parameters. The number of automobiles has also grown quickly to meet the enormous population. Additionally, this resulted in an increase in accidents. The accident prevention strategies now in use are all static and dated. Additionally, there is no reliable accident detection system. Automobile vehicle parameters are continuously monitored by a microcontroller which stores the data logs containing vehicle parameter data into a sheltered digital memory card and in the cloud storage. The system doesn't solely record the vehicle parameters data of the automobile periodically, but also actively monitors for any sudden vehicle accident detection. The sensor may facilitate folks to analyze the accident quickly and lawfully when a collision happens to alert the emergency services to that location. The system will update the information whenever an abnormal system event happens. A black box in a vehicle gather driving information about the vehicle before, during and after a crash

Near-quantum-limited haloscope search for dark-photon dark matter enhanced by a high- Q superconducting cavity

We report new experimental results on the search for dark photons based on a near-quantum-limited haloscope equipped with a superconducting cavity. The loaded quality factor of the superconducting cavity is 6×105, so that the expected signal from dark-photon dark matter can be enhanced by more than one order compared to a copper cavity. A Josephson parametric amplifier with a near-quantum-limited noise temperature has been utilized to minimize the noise during the search. Furthermore, a digital acquisition card based on field programmable gate arrays has been utilized to maximize data collection efficiency with a duty cycle being 100%. This work has established the most stringent constraints on dark photons at around 26.965 μeV. In the future, our apparatus can be extended to search for other dark matter candidates, such as axions and axionlike particles, and scrutinize new physics beyond the Standard Model. Published by the American Physical Society 2024

Portable Arduino-Based Multi-Sensor Device (SBEDAD): Measuring the Built Environment in Street Cycling Spaces.

The built environment's impact on human activities has been a hot issue in urban research. Compared to motorized spaces, the built environment of pedestrian and cycling street spaces dramatically influences people's travel experience and travel mode choice. The streets' built environment data play a vital role in urban design and management. However, the multi-source, heterogeneous, and massive data acquisition methods and tools for the built environment have become obstacles for urban design and management. To better realize the data acquisition and for deeper understanding of the urban built environment, this study develops a new portable, low-cost Arduino-based multi-sensor array integrated into a single portable unit for built environment measurements of street cycling spaces. The system consists of five sensors and an Arduino Mega board, aimed at measuring the characteristics of the street cycling space. It takes air quality, human sensation, road quality, and greenery as the detection objects. An integrated particulate matter laser sensor, a light intensity sensor, a temperature and humidity sensor, noise sensors, and an 8K panoramic camera are used for multi-source data acquisition in the street. The device has a mobile power supply display and a secure digital card to improve its portability. The study took Beijing as a sample case. A total of 127.97 G of video data and 4794 Kb of txt records were acquired in 36 working hours using the street built environment data acquisition device. The efficiency rose to 8474.21% compared to last year. As an alternative to conventional hardware used for this similar purpose, the device avoids the need to carry multiple types and models of sensing devices, making it possible to target multi-sensor data-based street built environment research. Second, the device's power and storage capabilities make it portable, independent, and scalable, accelerating self-motivated development. Third, it dramatically reduces the cost. The device provides a methodological and technological basis for conceptualizing new research scenarios and potential applications.

Imperative Strategy of Digital Transformation: A Case Study of Surabaya City's Digital ID Card Identity

Digitalization is an innovation based on technological advances that can make governance more effective and efficient. This makes human activities carry out digital transformation in both the public and private sectors. One of the implementations of digital transformation in the public sector is the implementation of Digital ID cards. Digital transformation in the context of digital ID cards must be balanced with the readiness of both implementers and the community as policy actors. This research identifies digital transformation in the context of Digital KTP in Surabaya City using the imperative strategy theory of digital transformation model Verhoef which has 4 indicators, namely: Digital Resources, Organizational Structure, Improvement Strategy, and Measures and Goals. Data is obtained through analysis of observation results, documentation, and interviews with implementing agencies and the community. The results of the study found that there was a 25% target non-achievement from the Ministry of Home Affairs of the Republic of Indonesia for the activation of Digital KTP in Surabaya, this was due to a less massive improvement strategy and a lack of public awareness regarding this innovation. This study concludes that there are still indicators that have obstacles such as digital resources, which in its implementation there are still obstacles in the IKD application and growth strategies that still need strategies to reach the elderly and add features to increase the value of innovation to increase public awareness of digital transformation.

Comparative Analysis of Fake Product Identification System Using Blockchain Technology

Fictitious products have emerged as a substantial challenge in the manufacturing sector, inflicting adverse consequences on a company's financial health, reputation, and overall prosperity. Thankfully, blockchain technology provides an effective remedy for discerning fake items and verifying the legitimacy of authentic ones, all within a decentralized and widely distributed digital ledger. Quick Response (QR) codes serve as pivotal tools in the fight against fictitious goods, as each product is now furnished with a QR code that acts as a direct bridge to the blockchain system, essentially bestowing each item with a digital identification card. QR code scanners communicate with the blockchain to promptly validate whether a product is genuine or fictitious. Moreover, customers can harness this technology to track a product's journey through the supply chain and authenticate ownership details, akin to a digital breadcrumb trail that securely preserves product information and unique codes as database blocks. Considering the globalized business landscape and the perpetual advancements in technology, industrial manufacturers and distributors are wholeheartedly committed to optimizing their supply chain processes, ensuring they remain one step ahead of fictitious product proliferation and fortifying their operations against the dissemination of spurious items. In this paper we compare Different Fake product identification Methods like Barcodes, QR Codes, RFID Tags, Serial numbers with methods using Blockchain technology which is having high security, transferability & traceability throughout Supply Chain.

Protection of Personal Data in the Use of Digital ID Cards against Misuse of Data from Cyber Hack

Protection of Personal Data in the Use of Digital ID Cards against Misuse of Data from Cyber Hack

Digital vs. Hybrid: Comparing Two Versions of a Board Game for Teacher Training

This study compares two versions (one digital, one hybrid) of a serious board game for teacher training called the “4Ts game”. Teachers play the game in groups to learn about—and directly engage in—the joint design of collaborative learning activities for their students by choosing the Tasks to be proposed, the Timing of activities, the Technologies to be used, and the Team composition, in an iterative process of decision making. The game comes in three versions: fully tangible, digital, and hybrid. This paper focuses on the interaction design of the digital and hybrid versions. In both cases, teachers pick cards up from four decks, read the prompts provided in the cards, and place them on a board to design a learning activity together. Their decision-making process is scaffolded by the digital or hybrid game versions, which provide feedback and suggestions and guide teachers toward the creation of a coherent design. The user experience is quite different in the two formats. In the hybrid game, teachers physically manipulate tangible cards on a tabletop board, and the board status is replicated on a laptop application that displays automatic feedback and guidance. By contrast, the digital version is played using an Interactive Whiteboard with touch-screen capabilities, thereby allowing teachers to manipulate digital cards on a digital board. The game was used in the context of two training initiatives targeting in-service school teachers (N = 42). Data were collected on acceptance of the model upon which the game is built, acceptance of the game itself, overall user satisfaction, and knowledge gains. Results show that teachers generally liked both versions of the game, especially the opportunity provided for receiving guidance in the design process. Additionally, teachers’ knowledge about learning design and collaborative learning increased significantly between the pre- and post-test for both the digital and the hybrid game groups. However, few significant differences were found between the groups that used the digital and hybrid versions of the game: the digital version was perceived as being slightly easier to use (p < 0.001). Overall, the study suggests that both versions of the game have the potential for teacher training, while the user interface of the hybrid version should be further refined to fully harness the game’s potential.

Formation of the foreign language competence of future physical education teachers when working with digital didactic flash cards

The problem and the aim of the study. Modernization of higher education opens up new prospects for the use of electronic resources in ensuring the quality of foreign language education. The use of interactive tools (simulators, flash cards, virtual boards) meets the requirements for training programs of physical education teachers and the challenges of the international sports movement. The purpose of the work is to study the possibilities of using digital flash cards in training future physical education teachers to develop their foreign language communicative competence. Research methods. The study involved 54 first- and second-year students of Vyatka State University (Faculty of Pedagogy and Psychology) (Russian Federation). Training program: 44.03.01 Pedagogical education, Physical education and sports (bachelor's degree level). The Quizlet online platform was used to work with digital flash cards. The test contains questions grouped into the blocks “Digital educational technologies” and “Foreign language in communication (physical education and sports)”. For statistical processing of data, the Pearson's chi-squared test was used. Results. The system of working with flash cards in foreign language professional communication of physical education teachers is described: studying the functionality, working with ready-made sets of cards, automating and improving lexical units, developing thematic sets. A special feature of the program is the adaptation of its content to the specifics of the field of study. In independent work and online collaboration, students of the experimental group used Flashcards, Speller, Scatter, Quizlet Live modes. Statistically significant differences in the qualitative changes that occurred in the level of foreign language training were determined (χ2 = 8.179; p < 0.05). In conclusion, the possibilities of including flash cards in the training of physical education teachers are formulated: competition and receiving positive emotions; resources for self-development, etc. Difficulties are also highlighted: low initial level of language qualification and digital skills; different motivation; dependence of the learning process on sports specialization.

CreativeStone: A Creativity Booster for Hearthstone Card Decks

Digital Collectible Card Games (DCCG) rely on human expertise to create competitive card decks. The most effective decks are shared and become popular among players through online communities. Players then keep enhancing those decks by replacing cards and testing those new deck variations in online arenas. This fine-tuning process is time-consuming and most of the time leads to small improvements in the players win rate. This paper presents CreativeStone, a creativity booster for Hearthstone card decks. Our creativity-guided approach uses a genetic algorithm and the Regent-Dependent Creativity (RDC) metric to identify the core cards of an existing deck, and then improves it towards a more valuable and novel deck by adding cards that are synergic to the core cards, but also different from the ones in the original deck. Our experimental results show that CreativeStone can boost even legendary decks, outperforming handcrafted ones by 21% in win rate.

An Exploration on Utilization of Business Analytics in Sri Lankan Banks

In this era of data evangelism, organizations are evolving with a paradigm shift from intuition-driven decision making to evidence-based decision making. Thus, business analytics has become a popular buzzword in modern business. Banking is a lavish industry that generates massive amounts of data and has copious opportunities for the utilization of business analytics to reap its maximum return. Therefore, the significance of business analytics in banking cannot be ignored. Though some international studies have indicated the utilization of business analytics in banks, studies on Sri Lankan banks are quite scarce. To fill this gap, this paper investigates the current utilization of business analytics in the Sri Lankan banking industry. The paper adopted a qualitative approach with multiple case studies, interviewing five professionals from different private commercial banks who are well-versed in business analytics. The paper covers eight aspects of business analytics utilization: duration of use, delegation, beneficiaries, technological aid, essentiality, value realization, perceived usage, and future direction. It was found that most banks have started using business analytics during the last three to four years, mainly for digital banking and card operations with basic technologies such as Power BI and Tableau. Further, it was also found that most banks have realized the importance and potentiality of business analytics, but neither integrated it fully with their core business nor achieved the expected value creation. The paper concludes that Sri Lankan banks are still in the early stages of business analytics maturity. Thus, there is a need to overcome the challenges and implement strategies to leverage business analytics for their benefit. Importantly, this study will contribute to the body of knowledge in the field of business analytics and the Sri Lankan banking industry where related studies are scarce.

Application of an innovative approach to the organization of the educational process in higher education and training of applicants 073 and 281 specialties in the conditions of distance education

The study proved and substantiated the importance of innovative approaches and digitalization in the organization of the educational process of higher education. It has been found that the introduction of innovative approaches is a strategically key factor for achieving a high level of quality and efficiency of educational services. In particular, innovative technologies and digitalization allow universities to adapt to modern requirements and create flexible and accessible learning environments. 
 During the study, an analysis of differences in the interpretation of the concepts of «threat» and «risk» was conducted. In particular, it is determined that in education threats and risks can include not only financial difficulties, but also loss of reputation, low quality of education and insufficient competitiveness of graduates. It identifies the main range of problematic issues, sets of innovative approaches in higher education and highlights the principles and stages of diagnosis, which should take into account the specifics of the educational environment and the requirements of the modern labor market for its qualitative assessment. 
 In order to test the research, the article assesses and analyzes the introduction of innovative approaches in the Volodymyr Dahl East Ukrainian National University for the training of applicants 073 and 281 in the field of distance education. The strategic goals chosen to accelerate the digitalization process have been singled out and justified, considering the high standards of quality and the needs of the modern educational environment. The introduction of a digital student card, the creation of a digital educational environment and an increase in the level of digital literacy of students and teaching staff are key areas of the strategy of the Volodymyr Dahl East Ukrainian National University. In addition, innovative approaches have been developed, such as partnerships with technology companies, the creation of electronic libraries and archives aimed at supporting research activities and quality education in distance learning. 
 It provides a SWOT analysis of the Volodymyr Dahl East Ukrainian National University which highlights the main strengths and weaknesses of its functioning, as well as identifies the opportunities and threats faced by the university today in the most difficult conditions of existence. The conducted analysis allows us to draw conclusions and determine the prospects for further research in this direction. 
 In general, the study emphasizes the importance of innovation and digitalization in education as strategic factors contributing to improving the quality, efficiency, and competitiveness of educational institutions in the modern world. 
 The obtained results help to determine the optimal way to achieve the set goals, and their certification with certificates testifies to the importance and effectiveness of the chosen direction of innovative activity at Volodymyr Dahl East Ukrainian National University in the face of high requirements for remote educational process.

A dual-ligand lanthanide-based metal-organic framework for highly selective and sensitive colorimetric detection of Fe2.

Accumulation of heavy metals in humans and mammals causes health problems due to their abundance as transition metal ions. Iron (Fe2+) serves significantly in numerous biological processes as a heavy metal ion. In this study, we have designed and prepared a metal-organic framework (MOF) utilizing a one-step solvothermal process, incorporating a dual-ligand combination of terephthalic acid (H2BDC) and α,α',α''-tert-pyridine (TPY) with Eu3+ as the metal node. For this MOF, we termed it Eu-BDC/TPY. Eu-BDC/TPY has superior selectivity over other metal cations. It provides an accurate, sensitive, broad linear range colorimetric method for detecting Fe2+ in a concentration range of 1-50 μM with a modest limit of detection (0.33 μM). Eu-BDC/TPY detects the absence of Fe2+ quickly (within 5 seconds), which is very valuable in practical applications. In addition, the results can be used to create a digital image colorimetric card (DIC) using colorimetric software, enabling instantaneous detection of Fe2+ concentration using a smartphone.