Hbase configuration phpmunkák

I'm looking for a skilled developer to upgrade my site from PHP 7 to PHP 8.2. The current site has: - User registration and login functionality The site is built on Custom PHP, without the use of any specific frameworks or CMS. The ideal freelancer would have: - Strong experience with PHP - Previous experience with upgrading codebases from PHP 7 to PHP 8.2 - Familiarity with Custom PHP coding Please note that the client did not specify custom plugins or modules that need updating. However, it's important to anticipate and address any issues that may arise during the upgrade process. The selected freelancer should be able to identify and resolve any potential conflicts with the existing site's functionality.

I'm looking for a skilled network specialist to assist me in configuring my existing Unifi Gateway, CloudKey, and Access Points for enhanced security. Key Requirements: - Configuration of Unifi Gateway, CloudKey, and Access Points: The primary goal is to enhance the security of the network. Therefore, the specialist will need to ensure that the configuration aligns with this objective. Ideal Skills and Experience: - Proficiency with Unifi network devices: The specialist should have hands-on experience with Unifi Gateway and Access Points. Experience with CloudKey would be a plus. - Network Security Expertise: A strong understanding of network security principles and best practices is essential. Additional Information: - Although the Unifi Switch is part of my current ...

I need an expert to configure my email accounts for Domains 1, 2, and 3. In addition, I require the design and implementation of tailor-made survey forms based on a specific model I have in mind. - Email Configuration: I need my email accounts to be set up in an efficient way in these three domains. You should be experienced in domain management and email setup. - Form Creation: I will provide a specific model for the survey forms that need to be created. Previous experience with custom form creation and design is a must. Looking to get this project completed as soon as possible. Those who can deliver fast results will be given higher consideration.

I need a talented and experienced WordPress developer to finish with final touches to make it look professional and setting up my WordPress website to include contact form integration. Additionally, I want to ensure the website is fully secure by installing an SSL certificate. Specific requirements: - Improve the contact form on the website - Install and configure an SSL certificate for security For the custom email setup, I'd like to use Microsoft 365. Ideal Skills: - Strong experience in WordPress development - Expertise in setting up and configuring contact forms - Prior experience with SSL certificate installation - Familiarity with Namecheap custom e-mail integration with Microsoft 365 email setup - Excellent understanding of website security practices

I have a document with the specifications of webservices. I need with php consume this webservices and get responses and save some information in my database

I am looking for a knowledgeable freelancer who can provide training on Factory Talk administration console and Factory Talk view studio. The main tasks for the training are: - Configuration and customization - Troubleshooting and support The freelancer should also focus on these modules: - User management - Data logging and reporting - Alarm management Ideal freelancer skills and experience: - Intermediate proficiency in Factory Talk administration console and Factory Talk view studio. - Proven experience in configuration, customization, troubleshooting and support. - Knowledgeable in user management, data logging, reporting, and alarm management. The goal of the project is to become proficient in using Factory Talk console and view studio after the training....

...Key Requirements: - The configurator should include Patio furniture, Outdoor lighting, Garden tools, and Sunrooms. - It should allow customers to view products from all angles with a 360-degree product view. - They should also be able to customize the colors of each product. - A drag and drop functionality should be implemented so that customers can easily place products in their desired configuration. The aim is to offer a seamless, visually engaging, and interactive shopping experience for my customers. They should be able to see different furniture styles, lighting options, and tool categories in one place. The end result should be a user-friendly, intuitive tool that encourages customers to engage with my products and ultimately make a purchase. Ideal Skills and Experien...

I'm currently in need of a skilled individual proficient in Elementor and JetEngine to assist in finalizing the configuration of dynamic content imported from another site. The content, which includes Artists, Styles, and Portfolio Items, has been imported successfully (as a Crocoblock/JetEngine "skin" as well as Elementor archive and single templates), but requires further configuration to ensure it functions optimally on my website and fits the visual aesthetic. Key Tasks: - Configuring Custom Post Types (CPTs): The project involves working on Artists, Styles, and Portfolio Items. These should be set up in a user-friendly way so that I can easily manage and present the content on my site. - Establishing Relationships between CPTs & Building Complex Queri...

I'm looking for a freelancer to assist me in setting up my Clickback email marketing account, and manage it. In particular, I need help with the initial account setup, list configuration, and email template creation. Key tasks include: - Initial account setup: I would like someone to help me with the initial setup of my Clickback account, ensuring that all the necessary information is accurately inputted and that the account is correctly configured for my email marketing needs. - List configuration: I need assistance with creating email lists within Clickback, and ensuring that they are accurately segmented and organized. - Email template creation: I need someone to help me create an email template that is suitable for my marketing needs, and that reflects my brand ide...

The task at hand is to upgrade the PHP version of my content management system from 7.2 to 8.1. I have been using a PHP without any frameworks, and I'd like to keep it this way. I'm seeking a skilled developer well-versed in PHP and experienced in operations without frameworks. Your responsibilities will include: - Studying the existing PHP code - Carrying out the necessary modification for smooth running on PHP 8.1 without any performance degradation. - Testing and debugging post upgrade to ensure seamless system operation Please note, I need this work completed within 7 - 15 days.

I'm in need of an IT professi...notifications for a custom-built application. Key requirements and expectations for this project include: - Setting up an SMTP server specifically utilizing Sendmail software on a Debian server - Ensuring that the configuration is optimized for automated email notifications - Providing guidance or documentation on how to integrate the SMTP server with my custom-built application Ideal candidates for this project should possess the following skills and experience: - Proficiency in working with Debian servers and setting up SMTP servers - Prior experience with Sendmail configuration - Understanding of how to optimize SMTP servers for automated email notifications - Capability to provide clear documentation and guidance for integration wi...

I'm currently in need of a skilled individual proficient in Elementor and JetEngine to assist in finalizing the configuration of dynamic content imported from another site. The content, which includes Artists, Styles, and Portfolio Items, has been imported successfully (as a Crocoblock/JetEngine "skin" as well as Elementor archive and single templates), but requires further configuration to ensure it functions optimally on my website and fits the visual aesthetic. Key Tasks: - Configuring Custom Post Types (CPTs): The project involves working on Artists, Styles, and Portfolio Items. These should be set up in a user-friendly way so that I can easily manage and present the content on my site. - Establishing Relationships between CPTs & Building Complex Queri...

I need assistance with the configuration of our Tour Operator website's booking system. Specifically, we require someone to help implement an inquiry and payment solution from a third-party provider onto our website. This task is not overly complex, as we have all the necessary instructions and links to guide the implementation of the widget onto our website.

I'm in need of a PHP developer to assist with resolving a specific issue within my code, and also adjust some functionality related to user balances and payment processing. - The issue is isolated to a certain part of the codebase. I have a video that comprehensively explains the problem, saving you time on debugging and troubleshooting. - The main issue at hand involves the necessity of adjusting user balances and funds for payments. This requires a high level of precision and understanding of PHP functionality. Ideal candidates should have: - Proficient in PHP and associated technologies. - Strong problem-solving skills to address the issue quickly. - Experience in user balance management and payment systems is highly desirable.

I have a Contabo VPS with Linux OS that I need to be set up with Cloudpanel and properly configured on an urgent basis. Key Requirements: - Set up Cloudpanel on a Contabo VPS with Linux OS - Complete configuration and installation of Cloudpanel - Ensure the server is ready for immediate usage upon completion - Tighten security and optimize performance I am looking for an experienced server administrator with the following skills: - Proficient in setting up and configuring cloud server environments - In-depth knowledge of Linux operating systems, particularly CentOS - Familiarity with Cloudpanel or similar server management panels - Ability to work quickly and efficiently, meeting tight deadlines This is an urgent task, so I need someone who can start immediately and prioritize a...

I'm in urgent need of a PHP expert to assist in creating (or finish the unfinish project attach ) a server-side application that will use Google Drive API, Google Calendar API, and/or Google Contacts API. The main priority is to implement user sign-in functionality for the application to ensure secure access and authentication for users. Key Requirements: - Seamless integration of Google Drive API, Google Calendar API, and/or Google Contacts API into a PHP worker application. - Implementation of user sign-in features to authenticate users and provide secure access to the application. - Priority on the ability to upload files using Google Drive API. The ideal freelancer must have: - Proficiency in PHP and experience with server-side applications. - Expertise in ...

...to TestFlight. Development: - Flutter 3.19.0 - Android Studio (Jelly Fish) - THIS IS MANDATORY Key Requirements: - Generate the Android and iOS builds for an existing Flutter app - Push the iOS build to TestFlight - Proficient in managing and uploading builds on Apple Developer account Additional Information: - The Flutter app is integrated with push notifications. Please ensure that the configuration for these services is maintained in the builds. Ideal Skills: - Strong experience with Flutter - Proficient in iOS build generation and TestFlight distribution - Familiarity with Apple Developer account management and configurations - Understanding of push notification integration in Flutter Please provide your relevant experience and a clear strategy for managing the iOS bui...

I'm in need of a Laravel developer who's well-versed in setting up thermal printers, specifically Model A, to integrate with my Laravel application. The primary function I'm looking for is to enable this system for printing receipts. - Setup Model A thermal printer with Laravel - Enable printing receipts in the application It's important that the Laravel application specifically supports: - Thermal printer Model A - Printing of receipts - Single language, English (no need for multi-language support) Successful candidates should have: - Experience in Laravel application development - Proficiency with setting up thermal printers - Knowledge in working with printing functions in Laravel - Ability to optimize printing performance in Laravel applications.

As discussed in chat and outlined in the provided document, excluding referrals, support ticket and reports

...needs a certain amount of inputs and outputs to begin with, but also minimum 2 outputs with PWM-control or analog 0-5V, as the motorcontroller of choice works with PWM or 0-5V inputs. Also 2 analog inputs 0-5V for 2 kinds of safety edges. Find also the list of peripherals in the attachment. The pulse generated by the motorcontroller won’t exceed 500 Hz with our current motor/motorcontroller configuration. (see peripheral list: section motorcontroller) In total we need to have: Digital inputs: 12 Digital fast inputs (counter): 2 Analog inputs: 2 Digital outputs: 6 Analog outputs: 2 Key deliverable: A fully programmed NUCLEO-G491RE STM32 and ESP32-DEVKITC-32UE microcontroller that controls a sliding gate according to an already provided functional description (fragments of t...

...NodeJS and backed by a MYSQL database, needs immediate attention. Here's what needs to be done: User Interface Updates: The component related to photos in the application requires significant changes. I also need a feature that shows the GPS route to the specified delivery point. This functionality was not implemented in the initial version of the application. Additionally, changing screen configuration doesn't display corresponding states with their color (only changes upon updating the application). Functionality Improvements: On top of the UI changes, the app needs general functionality improvements to enhance user experience and the app's efficiency. Also, create a button for downloading PDF files; the PDF creation functionality is already developed, so only ...

Website Designer , Php , E Commerce having knowledge of MySQL

I have a business website that I need migrated to a new hosting service. Key Requirements: - The site is a business website with multiple pages - The site is not built on a CMS or framework, so web dev knowledge is a must Ideal Skills and Experience: - Proficiency in web development - Experience with website migration - Strong understanding of hosting servers and configuration - Ability to troubleshoot and solve problems as they arise. Backup already done

I am currently looking for an experienced individual to assist me in setting up the Facebook Conversions API on my WordPress website. Key Responsibilities: - Configuration and setting up of Facebook Conversions API on a WordPress platform Ideal Candidate: - Proficient in configuring and setting up the Facebook Conversions API - Well-versed in working with WordPress, understanding its architecture and integration requirements. Please note that I already have a Facebook Pixel installed and fully operational on the website.

...Arabic Site Activation, and SEO Configuration for WordPress Website I am seeking a skilled and experienced WordPress professional to help me with the following tasks for my website, which is an SEO Agency: Content Integration: I have a WordPress template already designed and the content in English is ready. Your task will be to integrate this content into the website in a visually appealing and organized manner. The website consists of approximately 20-30 pages. Arabic Site Activation: I am currently working on translating the content into Arabic. I need you to activate the Arabic version of the site and ensure that the Arabic content is integrated seamlessly, maintaining the same level of visual appeal and organization as the English site. SEO Configuration: Optimize ...

I need a skilled developer to create a graph logic application in either Core PHP, JavaScript, or JQuery. The application will focus on visualizing user engagement data, specifically the bounce rate. Key Requirements: - Develop a graph logic application that utilizes Core PHP, JavaScript, or JQuery. - The system should effectively visualize user engagement data. - The application should specifically focus on visualizing the bounce rate metric. Ideal Skills: - Proficiency in Core PHP, JavaScript, or JQuery. - Experience in developing graph logic applications. - Understanding of user engagement metrics.

Website PHP version updation..............

I'm in search of a specialist who can assist in installing a Flutter script for a full app on both iOS and Android, alongside the required admin panel. Key Requirements: - The Flutter script is already chosen; hence, the primary need is for installation and configuration. - The app design is ready in the form of a mockup, which will be provided to the successful freelancer. Ideal Skills and Experience: - Proficiency in Flutter and its setup is a must. - Familiarity with configuring admin panels for Flutter apps. - Prior experience in installing pre-made scripts for full app development. - Strong communication skills to ensure that the provided design mockup aligns perfectly with the final product. The role is primarily focused on the technical aspect of the project, rather ...

I'm seeking a skilled system administrator to replace my current MariaDB with MySQL 8.0 on a CentOS server. The ideal candidate will be able to: - Completely remove MariaDB ensuring no data loss - Install and configure MySQL 8.0, adhering to: * Default configuration * Custom storage engine Security is a key concern. Remote access to the MySQL installation must be restricted. This is crucial to maintain the integrity and security of the server and its data.

...filtering, distribution, and processing. Perform load testing to validate the system's ability to handle high message volumes. Documentation and Handover: Provide comprehensive documentation on the Apache Kafka setup, master script, and worker scripts. Include instructions for installation, configuration, and usage of the messaging system. Conduct a handover session to transfer knowledge and ensure smooth operation of the system. Requirements: Strong experience with Apache Kafka setup and configuration on Windows. Proficiency in Python programming language. Knowledge of distributed systems and messaging patterns. Familiarity with message filtering and processing techniques. Experience with testing and debugging distributed systems. Excellent problem-solving and...

I need someone to display my YouTube comments based on newest first. I use PHBB forum so I would like it shown on top. It can accept html and php I believe. It should only show 5 latest. So if you can create this on your site I can upload it to mine and so we can see this on a blank page. Then I need code to insert into my Phbb forum

I am looking for a cloud engineer who can assist with deploying an ASP.NET Web Form application on a Windows Server 2022 on VPS. Key Requirements: - The SQL Server DB and ASP.NE...task is to ensure the successful deployment of the ASP.NET Web Form application. Additional Details: - The cloud provider I am currently using is WABYNE. Ideal Skills and Experience: - Proficiency in cloud engineering and deployment processes. - Experience with ASP.NET Web Form applications. - Familiarity with Windows Server 2022 on VPS. - Knowledge of SSL certificate installation, database configuration, and firewall settings is a plus. Please provide your relevant experience, certifications, and portfolio when applying. Your approach to this project and estimated timeline will also be of interest. ...

I'm looking for a server administ...remains secure and up-to-date with the latest patches. - Regularly backing up the server's data to prevent loss in case of failure. - Updating and maintaining the Drupal installation, ensuring compatibility with the server setup. Ideal skills and experience: - Proficiency in Linux server administration and management. - Intermediate level of experience with Drupal, including installation and configuration. - Strong troubleshooting and problem-solving skills. - Understanding of best security practices for servers and websites. - Experience with regular data backup procedures. This is a long-term project with the potential for additional tasks as our systems grow. Please include examples of your previous work with both Linux servers and ...

I'm looking for a Salesforce CPQ Developer to assist with a variety of functionalities. Experience in Development, Visualforce Pages, Lightning Web Components, and Administration Strong understanding of CRM processes and functionality Experience with customization and enhancements Knowledge of Salesforce CPQ and CPQ configuration Experience with Salesforce integration and data migration Strong analytical and problem-solving skills Excellent written and verbal communication skills certifications are a plus Bachelor's degree in Computer Science, Information Technology, or related field Are you enthusiastic to accept new challenges and delivering a high performance , scalable solutions in Salesforce CPQ and meet below

I’m currently seeking an experienced developer for the creation of a CRM Application based on WordPress and PHP. This comprehensive CRM system will focus mainly on the following aspects: - Contact Management: Easy setup for adding new contacts, updating existing contacts, and generally ensuring robust record-keeping for clients. - Sales Pipeline Tracking: This feature will aid in tracking the progress of deals, identifying slow points, and pushing for efficient sales funnel management. - Customer Support Ticketing: A well-organized dashboard for support tickets, helping in prompt and effective resolution of customer issues. While the main features are outlined, I’m open to discussing additional functionalities that might enhance the system’s effectiveness. Integ...

I'm in need of a skilled PHP Yii 2 developer to create a robust platform with user authentication, API integration, and a payment gateway. Key project requirements: - Use1. We've implemented razor pay in frontend but in backend it's phone pe so order I'd is not coming we've to fix that 2. Currently login sign up is email id and password we've to change that flow to phone number OTP login and it's already there for forgot password flow we've to modify that and use it for login 3. Once payment is successful then there's an appointment booking api that needs to make an appointment there's small fixes in it 4. There's a doctor's profile api where it should give doctors fee sometime it's not coming These are the fix...

This project involves configuring Nginx on an AWS EC2 instance to properly serve a frontend React app under a custom domain while addressing SSL issues. Nginx configuration files need to be set up to ensure seamless access to the React site via the specified domain, resolving any SSL-related issues to ensure secure connections.

I'm in search of a PHP Developer with a proven track record of developing comprehensive ERP Solutions for the construction industry. We will looking for a ready application something more or less similar to our requirement. A existing pre developed application. Wherein customization can be done. Key Modules Required: - Quotation - Purchase - Project Management - Materials Management - Stock/Inventory - Billing - Accounts - Reports - Project Management - Cost Estimation - Procurement Specific Features for Project Management: - Task Management: The system should allow for easy task assignment and monitoring. - Resource Allocation: It should have a robust system for allocating and tracking resources. Specific Requirements for Cost Estimation: - Integrated Cost Database: The sy...

I need an experienced PHP developer to fix some issues in our existing code. The main problems are with the Search functionality and the Database Connection. Key responsibilities: - Fixing the broken search functionality - Resolving the database connection issues Your application should demonstrate: - Proven experience in PHP - Understanding of database connections and search functionalities - Good problem-solving skills Please include relevant experience in PHP in your proposal.

...assist with troubleshooting issues in my APC PowerChute Network Shutdown configuration. The main problem I'm facing is the failure to gracefully shut down connected devices, including servers, network equipment, and storage systems. Key Points: - The main issue is the failure to gracefully shut down connected devices. This is consistent across all devices and I need an expert who can identify the root cause and implement a solution. - The devices connected include servers, network equipment, and storage systems. - It's important that the freelancer has experience with APC PowerChute Network Shutdown configuration troubleshooting. Ideal Skills and Experience: - Proficiency in APC PowerChute Network Shutdown configuration. - Experience in troubleshootin...

I'm seeking an expert to set up my new Dell t150 with a Windows 10 operating system. The job entails: - Installing the Windows 10 OS, configuring it to suit my preferred settings - Installing Microsoft Office Suite, readying it for immediate use - Proposing and installing appropriate internet security measures Skills & experience ideal for the job: - Mastery in Windows 10 setup and configuration - Proficient in software installation, specifically Microsoft Office Suite - Experience in configuring robust internet security measures. I’m open to all effective suggestions. Remember, security is key!

I was configuring DNS settings on my WHM production server when I encountered cURL error 6: Could not resolve host. I need a skilled freelan...DNS settings on my WHM production server when I encountered cURL error 6: Could not resolve host. I need a skilled freelancer to help me troubleshoot and resolve this issue. Key Responsibilities: - Investigate the cURL error 6: Could not resolve host issue while configuring DNS on WHM - Analyze and identify the root cause of the problem - Resolve the issue effectively to ensure proper DNS configuration and functionality Ideal Skills: - Proficient in WHM and DNS configurations - Experience in troubleshooting cURL errors - Deep understanding of server environments and cPanel Your assistance in resolving this issue promptly will be greatly ap...

Hello there, I'm a volunteer from a community group, we are not incorporated but have been very active and ...objective spans threefold: - Reviewing the current install and identifying integration issues with WordPress - Making sure that the user roles on WordPress are created on CiviCRM - Review and fix errors with email integration to be able to send system email notifications and email campaigns Hence, I'm interested in a professional robustly competent in: - CiviCRM configuration and integration - CiviCRM Modules configuration - WordPress management - Member, contact, and account login management - Volunteer management - Designing newsletter and communications Help us with elevating our project engagement and interaction by applying your unique skills and ...

I'm in need of a skilled PHP developer to create a website much like www.websiteoutlook.com. The key features of the site will include: - The ability to provide website statistics - Domain information lookup - Primarily an information-driven purpose I'm looking for a professional who can deliver a high-quality site that is user-friendly and functional. The main skills required for this project are: - Proficiency in PHP - Experience in website development - Good understanding of website statistics and domain lookup services Experience with creating similar sites would be a plus.

FEATURES THAT I NEED TO BE IMPLEMENTED: -> FIRST MILESTONE: 1- INVESTMENT ENVIRONMENT, INTERCONNECTED WITH THE MATRIX THAT CURRENTLY OPERATES IN THE COMMUNITY. 1.1 THE USER CAN ONLY MAKE A CERTAIN INVESTMENT, ACCORDING TO HIS ADVANCES IN THE MATRIX. EX: COMPLETING YOUR: 1st LEVEL IN THE MATRIX, THE SYSTEM ALLOWS THE USER TO MAKE AN INVESTMENT OF UP TO 100$ 2ND LEVEL IN THE MATRIX: THE SYSTEM ALLOWS THE USER TO MAKE AN INVESTMENT OF UP TO 200$ 3rd LEVEL IN THE MATRIX: THE SYSTEM ALLOWS THE USER TO MAKE AN INVESTMENT OF UP TO $400 4TH LEVEL IN THE MATRIX: THE SYSTEM ALLOWS THE USER TO MAKE AN INVESTMENT OF UP TO $800 5th LEVEL IN THE MATRIX: THE SYSTEM ALLOWS THE USER TO MAKE AN INVESTMENT OF UP TO $1,200 6TH LEVEL IN THE MATRIX: THE SYSTEM ALLOWS THE USER TO MAKE AN INVESTMENT OF UP TO $...

I'm seeking a GitHub expert to help streamline our development process, focusing on version control. The primary objective is to improve our efficiency and code management through GitHub. Key deliverables include: - Establishing an effective branch management strategy - Enhanced merging and integration protocols - Configuration management optimization Ideal skills and experience for the job: - Proficient in GitHub - Strong understanding of version control - Previous experience in implementing branch management strategies - Proven track record in optimizing development processes Also looking for for solution How can we trace all the main Branches and sub branches for one application and what all the commits are there and what all in pending state which are not merged.. I c...

As a client whose project strongly relies on the functioning of OAuth 2.0, it's crucial to get assistance to solve an existent issue. Specifically, I'm...to rectify this issue and ensure the 401 unauthorized error message no longer exists. Ideal Skills and Experiences are: - OAuth 2.0 Specialist - Extensive experience in managing access tokens - Strong knowledge of protected resources configuration - Proven expertise in implementing authorization servers - Prior experience in handling issues related to authorization grant type - Experience with ServiceNow I'm not only looking for someone to help solve this issue, but also to prevent a similar occurrence in the future by bolstering the OAuth 2.0 configuration. Therefore, your ability to provide long-term sol...

I'm currently having difficulties with my Windows VM network connection when I configure it to use the Internal network type in Hyper-V. Despite setting it up, my VM is not connecting to the internet and displaying a 'No Internet' error message. Key Points: - My host machine runs on Windows. - I'm using Hyper-V as my virtualization software. - The network type I'm trying to configure is Internal. Requirements: - Troubleshoot the current network settings of my Windows VM on Hyper-V. - Resolve the 'No Internet' error and ensure the internet connectivity. - Perform necessary configurations to establish a successful connection over an Internal network type. Ideal Skills and Experience: - Proficiency in Windows operating system and Hyper-V. - Strong experie...

OTA upgrade tool program Pure command line tool Parameter control Output log to file Including nginx view log directory function configuration use UDP

We are looking for an experienced freelancer to create a custom DMA firmware using this simple guide : The guide provides detailed instructions, but I lack the ...simple guide : The guide provides detailed instructions, but I lack the time to complete it myself. The project will be executed on a Squirrel 35t board and should not take more than 3-4 hours for someone proficient. **Tasks:** - Configure and customize firmware based on pcileech-fpga - Use Vivado for development - Emulate TLP and configure the configuration space **Required Skills:** - FPGA design and programming - Experience with Vivado (Xilinx) - DMA firmware development - Verilog/VHDL programming - Debugging and testing embedded systems