Pembangkit Listrik Tenaga Panas Bumi yang dikelola PLN

Berikut ini uraian Pembangkit Listrik Tenaga Panas Bumi (PLTP) dan Pengelolaannya oleh PLN.
 
Pada tahun 2025, PLN menargetkan baruan EBT di Indonesia mencapai 23%. Untuk dapat mencapai target tersebut PLN selalu konsisten dalam penggunaan energi bersih ini terbukti dalam keseriusan PLN dalam mengelola dan mengembangkan pembangkit berbasis panas bumi yang ramah lingkungan ini.
 
Hingga saat ini, PLN Group telah mengelola tujuh PLTP dengan total kapasitas 572 MW. Tujuh PLTP diantaranya adalah PLTP Ulubelu, Lahendong, Ulumbu, Mataloko, Darajat, Gunung Salak dan Kamojang dengan nilai asset sebesar Rp. 12,3 triiun per 31 Desember 2020. Saat ini PLTP Kamojang juga telah tersertifikasi REC, lho.
 
 
Berikut daftar PLTP yang dikelola oleh PLN:
  • PLTP Ulubelu
  • PLTP Lahendong
  • PLTP Ulumbu
  • PLTP Mataloko
  • PLTP Darajat
  • PLTP Gunung Salak
  • PLTP Kamojang
Sampai dengan Tahun 2030 nanti, PLN berencana akan mengembangkan panas bumi dengan total kapasitas sekitar 725 MW. Kedepannya, total portofolio pengelolaan panas bumi akan mencapai kurang lebih 1.297 MW pada tahun 2030. 
 

 

Twitter Links

 

Twitter tags

  • https://twitter.com/hashtag/PowerBeyondGenerations
  • https://twitter.com/hashtag/PLNGreen
  • https://twitter.com/hashtag/PLNDukungEBT
  • https://twitter.com/hashtag/PLTP_PLN

 

 

Preprocessing Data pada Scikit Learn

Standard Scaler: semua fitur (input) memiliki nilai rata-rata 0 dan variansi=1
Robust Scaler: seperti Standard Scaler, namun menggunakan median dan kuartil
MinMax Scaler: semua fitur memiliki nilai minimum 0 dan nilai maksimum 1
Normalizer: semua fitur diperlakukan sebagai vektor, dan panjang euclidian dibuat menjadi 1. Dipakai kalau kita hanya perlu besaran arah/sudut/rasio dari vektor, dan tidak memerlukan nilai mutlaknya.

Internet of Things Untuk Aplikasi Militer

 

Internet of Battlefield Things
Internet of Battlefield Things

Berikut ini teknologi-teknologi yang dipakai untuk IoT pada militer [PTM2016]

Teknologi untuk IoT pada militer
Teknologi untuk IoT pada militer

 

Referensi Texbook

Referensi Jurnal

Referensi Artikel

 

Teknik Pengukuran Trafik ke Suatu Domain

Pengukuran trafik web ke suatu domain dan semua sub domainnya dapat dilakukan dengan beberapa cara:

  • analisis log di semua web server. Paling tepat, cuma lumayan melelahkan kalau dalam suatu lembaga/perusahaan terdapat banyak web server.
  • analisis jumlah trafik di port 80 dan 443 dari luar organisasi ke dalam organisasi tersebut. Angka ini bisa didapat dari log router organisasi,  namun mesti lognya mesti diaktifkan dulu, dan routernya mendukung. Kalau tidak diaktifkan, rekamannya tidak ada.
  • menggunakan Google Search Console, yaitu rekaman Google Search. Keuntungannya data ini tersedia gratis di Google, dan kita tidak perlu melakukan konfigurasi apapun di server kita. . Kelemahan: hanya mencatat trafik yang berasal dari Google search engine. Trafik dari search engine lain, dari website lain tidak tercatat. Mestinya data trafik Google cukup mewakili, karena biasanya mayoritas trafik web ke suatu organisasi berasal dari hasil search engine Google.
Tampilan Google Search Console
Tampilan Google Search Console

Referensi

Prosesor Intel Core i3-6100

Hari ini merakit Desktop PC dengan prosesor Intel Core i3-6100

Prosesor ini dijual dalam kemasan box, dan tray. Kemasan Box lebih mahal daripada tray. Foto di sini menunjukkan prosesor yang dikemas dalam bentuk tray. Kemasan ini penampilannya tidak menarik, namun harganya lebih murah. Yang perlu diperhatikan adalah kemasan ini direkat dengan selotip, sehingga ada sisa selotip di bagian atas prosesornya. Sisa selotip ini mesti dihilangkan sebelum memasang kipas pendingin & heatsink.

Kipas pendingin prosesor

Proses pemasangan CPU pada mainboard relatif sederhana (kalau sudah biasa).

Referensi

  • https://ark.intel.com/content/www/us/en/ark/products/90729/intel-core-i3-6100-processor-3m-cache-3-70-ghz.html

Security Infografik

Sumber:

  • https://twitter.com/SecurityGuill
  • https://securityguill.com/
  • https://twitter.com/SecurityGuill/status/1368241476753371140

How does an Antivirus works?

What is a Botnet & How it works

What is a Bug Bounty?

What is a DDos Attack?

What is DNS Poisoning & How it works?

How End-to-End Encryption Works

Nine Elements of Digital Forensic Process

What is a Fork Bomb

The 5 main steps of Hacking Process

What is a Honeypot

What is IDS & IPS

Some infosec Terms

What is Jackpotting

What is Kerberos and How It Works?

What is Kubernetes

What is LDAP and How It Works?

Some Basic Linux COmmands

What is Metasploit?

What is MFA

What is Mimikatz?

How does Mirai Botnet Works?

Man in The Middle Attack

What is Nmap

Most Critical Web App Security Risks

Some types of phishing attacks

The main programming languges in Infosec and their main uses

What is ransomware and how it works

Some good practices to avoid social engineering attack

Major flaws in an Information System

What is Signal

What is Software Reverse Engineering

Tools Useful for Forensic Analysis

Online Tools to analyze vulnerabilities and malware of websites

Tools for OSINT

What is TOR and how it works

Vulnerability Scanners

Most common vulnerabilities in web application

What is Wireshark?

What is XSS attack?

What is Zed Attack Proxy

Infosec Tools

Free Ebook: Applications of Deep Neural Networks

Where to get it:

Abstract

Deep learning is a group of exciting new technologies for neural networks. Through a combination of advanced training techniques and neural network architectural components, it is now possible to create neural networks that can handle tabular data, images, text, and audio as both input and output. Deep learning allows a neural network to learn hierarchies of information in a way that is like the function of the human brain. This course will introduce the student to classic neural network structures, Convolution Neural Networks (CNN), Long Short-Term Memory (LSTM), Gated Recurrent Neural Networks (GRU), General Adversarial Networks (GAN), and reinforcement learning. Application of these architectures to computer vision, time series, security, natural language processing (NLP), and data generation will be covered. High-Performance Computing (HPC) aspects will demonstrate how deep learning can be leveraged both on graphical processing units (GPUs), as well as grids. Focus is primarily upon the application of deep learning to problems, with some introduction to mathematical foundations. Readers will use the Python programming language to implement deep learning using Google TensorFlow and Keras. It is not necessary to know Python prior to this book; however, familiarity with at least one programming language is assumed.

Contents

Introduction                                               

 Python Preliminaries

  • Assignments                                         
  • Your Instructor: Jeff Heaton                                
  • Course Resources                                       
  • What is Deep Learning                                   
  • What is Machine Learning                                  
  • Regression                                           
  • Classification                                         
  • Beyond Classification and Regression                            
  • What are Neural Networks                                 
  • Why Deep Learning?                                     
  • Python for Deep Learning                                  
  • Software Installation                                     
  • Python Introduction                                     
  • Jupyter Notebooks                                      
  • Python Versions                                       
  • Module Assignment                                     
  • Introduction to Python                                  
  • Python Lists, Dictionaries, Sets and JSON                       
  • Lists and Tuples                                       
  • Sets                                              
  • Maps/Dictionaries/Hash Tables                               
  • More Advanced Lists                                     
  • An Introduction to JSON                                  
  • File Handling                                       
  • Read a CSV File                                       
  • Read (stream) a Large CSV File                              
  • Read a Text File                                       
  • Read an Image                                        
  • Functions, Lambdas, and Map/Reduce                         
  • Map                                              
  • Filter                                             
  • Lambda                                            
  • Reduce                                            

Python for Machine Learning

  • Introduction to Pandas                                  
  • Missing Values                                        
  • Dealing with Outliers                                    
  • Dropping Fields                                       
  • Concatenating Rows and Columns                             
  • Training and Validation                                   
  • Converting a Dataframe to a Matrix                            
  • Saving a Dataframe to CSV                                 
  • Saving a Dataframe to Pickle                                
  • Module Assignment                                     
  • Categorical and Continuous Values                           
  • Encoding Continuous Values                                
  • Encoding Categorical Values as Dummies                         
  • Target Encoding for Categoricals                              
  • Encoding Categorical Values as Ordinal                          
  • Grouping, Sorting, and Shuffling                             
  • Shuffling a Dataset                                      
  • Sorting a Data Set                                      
  • Grouping a Data Set                                     
  • Apply and Map                                      
  • Using Map with Dataframes                                 
  • Using Apply with Dataframes                                
  • Feature Engineering with Apply and Map                         
  • Feature Engineering                                    
  • Calculated Fields                                       
  • Google API Keys                                       
  • Other Examples: Dealing with Addresses                         

 Introduction to TensorFlow

  • Deep Learning and Neural Network Introduction                    
  • Classification or Regression                                 
  • Neurons and Layers                                     
  • Types of Neurons                                       
  • Input and Output Neurons                                 
  • Hidden Neurons                                       
  • Bias Neurons                                         
  • Context Neurons                                       
  • Other Neuron Types                                     
  • Why are Bias Neurons Needed?                               
  • Modern Activation Functions                                
  • Linear Activation Function                                 
  • Rectified Linear Units (ReLU)                               
  • Softmax Activation Function                                
  • Classic Activation Functions                                
  • Step Activation Function                                  
  • Sigmoid Activation Function                                
  • Hyperbolic Tangent Activation Function                          
  • Why ReLU?                                         
  • Module Assignment                                     
  • Introduction to Tensorflow and Keras                          
  • Why TensorFlow                                       
  • Deep Learning Tools                                     
  • Using TensorFlow Directly                                 
  • TensorFlow Linear Algebra Examples                           
  • TensorFlow Mandelbrot Set Example                           
  • Introduction to Keras                                    
  • Simple TensorFlow Regression: MPG                           
  • Introduction to Neural Network Hyperparameters                    
  • Controlling the Amount of Output                             
  • Regression Prediction                                    
  • Simple TensorFlow Classification: Iris                           
  • Saving and Loading a Keras Neural Network                      
  • Early Stopping in Keras to Prevent Overfitting                     
  • Early Stopping with Classification                             
  • Early Stopping with Regression                               
  • Extracting Weights and Manual Network Calculation                 
  • Weight Initialization                                     
  • Manual Neural Network Calculation                            

 Training for Tabular Data

  • Encoding a Feature Vector for Keras Deep Learning                  
  • Generate X and Y for a Classification Neural Network                  
  • Generate X and Y for a Regression Neural Network                   
  • Module Assignment                                     
  • Multiclass Classification with ROC and AUC                      
  • Binary Classification and ROC Charts                           
  • ROC Chart Example                                     
  • Multiclass Classification Error Metrics                           
  • Calculate Classification Accuracy                              
  • Calculate Classification Log Loss                              
  • Keras Regression for Deep Neural Networks with RMSE               
  • Mean Square Error                                      
  • Root Mean Square Error                                  
  • Lift Chart                                           
  • Training Neural Networks                                 
  • Classic Backpropagation                                   
  • Momentum Backpropagation                                
  • Batch and Online Backpropagation                             
  • Stochastic Gradient Descent                                 
  • Other Techniques                                       
  • ADAM Update                                        
  • Methods Compared                                     
  • Specifying the Update Rule in Tensorflow                         
  • Error Calculation from Scratch                              
  • Regression                                           
  • Classification                                         

 Regularization and Dropout

  • Introduction to Regularization: Ridge and Lasso                    
  • L and L Regularization                                  
  • Linear Regression                                       
  • L (Lasso) Regularization                                  
  • L (Ridge) Regularization                                  
  • ElasticNet Regularization                                  
  • Using K-Fold Cross-validation with Keras                        
  • Regression vs Classification K-Fold Cross-Validation                   
  • Out-of-Sample Regression Predictions with K-Fold Cross-Validation          
  • Classification with Stratified K-Fold Cross-Validation                  
  • Training with both a Cross-Validation and a Holdout Set                
  • L and L Regularization to Decrease Overfitting                   
  • Drop Out for Keras to Decrease Overfitting                       
  • Benchmarking Regularization Techniques                        
  • Additional Reading on Hyperparameter Tuning                      
  • Bootstrapping for Regression                                
  • Bootstrapping for Classification                               
  • Benchmarking                                        

 Convolutional Neural Networks (CNN) for Computer Vision

  • Image Processing in Python                               
  • Creating Images (from pixels) in Python                          
  • Transform Images in Python (at the pixel level)                     
  • Standardize Images                                      
  • Adding Noise to an Image                                  
  • Module Assignment                                     
  • Keras Neural Networks for Digits and Fashion MNIST                
  • Computer Vision                                       
  • Computer Vision Data Sets                                 
  • MNIST Digits Data Set                                   
  • MNIST Fashion Data Set                                  
  • CIFAR Data Set                                       
  • Other Resources                                       
  • Convolutional Neural Networks (CNNs)                          
  • Convolution Layers                                      
  • Max Pooling Layers                                     
  • TensorFlow with CNNs                                   
  • Access to Data Sets – DIGITS                                
  • Display the Digits                                      
  • Training/Fitting CNN – DIGITS                              
  • Evaluate Accuracy – DIGITS                                
  • MNIST Fashion                                        
  • Display the Apparel                                     
  • Training/Fitting CNN – Fashion                              
  • Implementing a ResNet in Keras                             
  • Keras Sequence vs Functional Model API                         
  • CIFAR Dataset                                        
  • ResNet V                                          
  • CONTENTS ix
  • ResNet V                                          
  • Using Your Own Images with Keras                           
  • Recognizing Multiple Images with Darknet                       
  • How Does DarkNet/YOLO Work?                             
  • Using YOLO in Python                                   
  • Installing YoloV-TF                                    
  • Transfering Weights                                     
  • Running DarkFlow (YOLO)                                 
  • Module Assignment                                     

 Generative Adversarial Networks

  • Introduction to GANS for Image and Data Generation                
  • Implementing DCGANs in Keras                            
  • Face Generation with StyleGAN and Python                      
  • Keras Sequence vs Functional Model API                         
  • Generating High Rez GAN Faces with Google CoLab                  
  • Run StyleGan From Command Line                           
  • Run StyleGAN From Python Code                            
  • Examining the Latent Vector                                
  • GANS for Semi-Supervised Training in Keras                      
  • Semi-Supervised Classification Training                          
  • Semi-Supervised Regression Training                            
  • Application of Semi-Supervised Regression                        
  • An Overview of GAN Research                              
  • Select Projects                                        

 Kaggle Data Sets

  • Introduction to Kaggle                                  
  • Kaggle Ranks                                         
  • Typical Kaggle Competition                                 
  • How Kaggle Competition Scoring                              
  • Preparing a Kaggle Submission                               
  • Select Kaggle Competitions                                 
  • Module Assignment                                     
  • Building Ensembles with Scikit-Learn and Keras                    
  • Evaluating Feature Importance                               
  • Classification and Input Perturbation Ranking                      
  • Regression and Input Perturbation Ranking                        
  • Biological Response with Neural Network                         
  • What Features/Columns are Important                          
  • Neural Network Ensemble                                  
  • Architecting Network: Hyperparameters                        
  • Number of Hidden Layers and Neuron Counts                       
  • Activation Functions                                     
  • Advanced Activation Functions                               
  • Regularization: L, L, Dropout                              
  • Batch Normalization                                     
  • Training Parameters                                     
  • Experimenting with Hyperparameters                           
  • x CONTENTS
  • Bayesian Hyperparameter Optimization for Keras                   
  • Current Semester’s Kaggle                                
  • Iris as a Kaggle Competition                                
  • MPG as a Kaggle Competition (Regression)                        
  • Module Assignment                                     

 Transfer Learning

  • Introduction to Keras Transfer Learning                        
  • Transfer Learning Example                                 
  • Module Assignment                                     
  • Popular Pretrained Neural Networks for Keras                     
  • DenseNet                                           
  • InceptionResNetV and InceptionV                            
  • MobileNet                                           
  • MobileNetV                                         
  • NASNet                                            
  • ResNet, ResNetV, ResNeXt                                
  • VGG and VGG                                     
  • Xception                                           
  • Transfer Learning for Computer Vision and Keras                   
  • Transfer                                            
  • Transfer Learning for Languages and Keras                       
  • Transfer Learning for Keras Feature Engineering                    

 Time Series in Keras

  • Time Series Data Encoding                               
  • Module Assignment                                     
  • Programming LSTM with Keras and TensorFlow                   
  • Understanding LSTM                                    
  • Simple TensorFlow LSTM Example                            
  • Sun Spots Example                                     
  • Further Reading for LSTM                                 
  • Text Generation with LSTM                              
  • Additional Information                                   
  • Character-Level Text Generation                              
  • Image Captioning with Keras and TensorFlow                    
  • Needed Data                                         
  • Running Locally                                       
  • Clean/Build Dataset From Flickrk                            
  • Choosing a Computer Vision Neural Network to Transfer                
  • Creating the Training Set                                  
  • Using a Data Generator                                   
  • Loading Glove Embeddings                                 
  • Building the Neural Network                                
  • Train the Neural Network                                  
  • Generating Captions                                     
  • Evaluate Performance on Test Data from Flickerk                    
  • Evaluate Performance on My Photos                            
  • Module Assignment                                     
  • CONTENTS xi
  • Temporal CNN in Keras and TensorFlow                       
  • Sun Spots Example – CNN                                 

 Natural Language Processing and Speech Recognition

  • Getting Started with Spacy in Python                         
  • Installing Spacy                                       
  • Tokenization                                         
  • Sentence Diagramming                                    
  • Stop Words                                          
  • WordVec and Text Classification                           
  • Suggested Software for WordVec                              
  • What are Embedding Layers in Keras                         
  • Simple Embedding Layer Example                             
  • Transferring An Embedding                                 
  • Training an Embedding                                   
  • Natural Language Processing with Spacy and Keras                 
  • Word-Level Text Generation                                
  • Learning English from Scratch with Keras and TensorFlow             
  • Imports and Utility Functions                                
  • Getting the Data                                       
  • Building the Vocabulary                                   
  • Building the Training and Test Data                            
  • Compile the Neural Network                                
  • Train the Neural Network                                  
  • Evaluate Accuracy                                      
  • Adhoc Query                                         

 Reinforcement Learning

  • Introduction to the OpenAI Gym                            
  • OpenAI Gym Leaderboard                                 
  • Looking at Gym Environments                               
  • Render OpenAI Gym Environments from CoLab                     
  • Introduction to Q-Learning                               
  • Introducing the Mountain Car                               
  • Programmed Car                                       
  • Reinforcement Learning                                   
  • Running and Observing the Agent                             
  • Inspecting the Q-Table                                    
  • Keras Q-Learning in the OpenAI Gym                         
  • DQN and the Cart-Pole Problem                              
  • Hyperparameters                                       
  • Environment                                         
  • Agent                                             
  • Policies                                            
  • Metrics and Evaluation                                   
  • Replay Buffer                                         
  • Data Collection                                        
  • Training the agent                                      
  • Visualization                                         
  • KS-Statistic                                          
  • Detecting Drift between Training and Testing Datasets by Training          
  • Using a Keras Deep Neural Network with a Web Application            
  • Converting Keras to CoreML                                
  • Creating an IOS CoreML Application                           
  • More Reading                                         
  • Other Neural Network Techniques
  • What is AutoML                                     
  • AutoML from your Local Computer                            
  • AutoML from Google Cloud                                 
  • A Simple AutoML System                                  
  • Running My Sample AutoML Program                          
  • Using Denoising AutoEncoders in Keras                        
  • Function Approximation                                   
  • Multi-Output Regression                                  
  • Simple Autoencoder                                     
  • Autoencode (single image)                                  
  • Standardize Images                                      
  • Image Autoencoder (multi-image)                             
  • Adding Noise to an Image                                  
  • Denoising Autoencoder                                   
  • Anomaly Detection in Keras                              
  • Read in KDD Data Set                                  
  • Preprocessing                                         
  • Training the Autoencoder                                  
  • Detecting an Anomaly                                    
  • Training an Intrusion Detection System with KDD                 
  • Read in Raw KDD- Dataset                               
  • Analyzing a Dataset                                     
  • Encode the feature vector                                  
  • Train the Neural Network                                  
  • New Technologies                                     
  • Neural Structured Learning (NSL)                             
  • Bert, AlBert, and Other NLP Technologies                        
  • Explainability Frameworks                               

Advanced/Other Topics

  • Flask and Deep Learning Web Services                        
  • Flask Hello World                                      
  • MPG Flask                                          
  • Flask MPG Client                                      
  • Images and Web Services                                  
  • Part : Deploying a Model to AWS                               
  • Train Model (optionally, outside of AWS)                         
  • Next Step: Convert Model (must use AWS SageMaker Notebook)           
  • Step Set up                                         
  • Step Load the Keras model using the JSON and weights file              
  • Step Export the Keras model to the TensorFlow ProtoBuf format (must use AWS
  • SageMaker Notebook)                                    
  • Step Convert TensorFlow model to a SageMaker readable format (must use AWS
  • SageMaker Notebook)                                    
  • Tar the entire directory and upload to S                         
  • Step Deploy the trained model (must use AWS SageMaker Notebook)         
  • Test Model Deployment (optionally, outside of AWS)              
  • Call the end point                                      
  • Additional Reading                                      
  • Using a Keras Deep Neural Network with a Web Application            
  • When to Retrain Your Neural Network                        
  • Preprocessing the Sberbank Russian Housing Market Data               
  • KS-Statistic                                          
  • Detecting Drift between Training and Testing Datasets by Training          
  • Using a Keras Deep Neural Network with a Web Application            
  • Converting Keras to CoreML                                
  • Creating an IOS CoreML Application                           
  • More Reading                                         
  • Other Neural Network Techniques
  • What is AutoML                                     
  • AutoML from your Local Computer                            
  • AutoML from Google Cloud                                 
  • A Simple AutoML System                                  
  • Running My Sample AutoML Program                          
  • Using Denoising AutoEncoders in Keras                        
  • Function Approximation                                   
  • Multi-Output Regression                                  
  • Simple Autoencoder                                     
  • Autoencode (single image)                                  
  • Standardize Images                                      
  • Image Autoencoder (multi-image)                             
  • Adding Noise to an Image                                  
  • Denoising Autoencoder                                   
  • Anomaly Detection in Keras                              
  • Read in KDD Data Set                                  
  • Preprocessing                                         
  • Training the Autoencoder                                  
  • Detecting an Anomaly                                    
  • Training an Intrusion Detection System with KDD                 
  • Read in Raw KDD- Dataset                               
  • Analyzing a Dataset                                     
  • Encode the feature vector                                  
  • Train the Neural Network                                  
  • New Technologies                                     
  • Neural Structured Learning (NSL)                             
  • Bert, AlBert, and Other NLP Technologies                        
  • Explainability Frameworks        

Pengendalian Banjir Jakarta

Master Plan 2020 Menurut PUPR

Berikut ini adalah skema master plan pengendalian banjir Jakarta menurut Kementerian PUPR (Kementerian Pekerjaan Umum dan Perumahan Rakyat)

Gambar di bawah ini adalah presentasi menteri PUPR setelah kasus banjir Januari 2020

Skema master plan pengendalian banjir Jakarta
Skema master plan pengendalian banjir Jakarta

Sumber dokumen aslinya dari “Skematik Pengendalian Banjir di DKI Jakarta” , gambar ini juga dirujuk di dokumen Kajian Pengelolaan Banjir DKI dan Sekitarnya Bagi Pembangunan Infrastruktur Berkelanjutan

Pada skema tersebut terdapat angka-angka debit sungai di Jakarta dan sekitarnya. Tidak disebutkan kemampuan drainage ke laut, serta pengaruh pasang surut.

Master Plan 1973

Penjelasan:

  1. Aliran air dari hulu DKI dialihkan ke Banjir Kanal langsung ke laut
  2. Aliran di wilayah selatan DKI dengan kontur tanah yang cukup tinggi mengalir secara gravitasi
  3. Di bagian utara yang rendah aliran air dikelola dengan sistem polder (tanggul, waduk dan pompa)
  4. Bagian hulu / selatan perlu dibangun / dilestarikan situ-situ, waduk dan penghijauan untuk menahan aliran air ke Jakarta

Hasil dari posting pak Muslim Muin: https://www.facebook.com/muslin.muin/posts/10218250932121467

Referensi