The purpose of this study is to develop instruments of critical thinking skills that meet the validity, reliability, and criteria for good items. This research includes development research which consists of the design and implementation stages. The analysis in the study used quantitative analysis with the Confirmatory Factor Analysis (CFA) Technique. The results showed that the value of t value> 1.96 (α <0.05) which means that each significant item measures critical thinking skills. The value of person reliability of 0.75 and item reliability of 0.94 means the consistency of the answers from the good subject. The quality of the items was analyzed using the QUEST program, indicating that the index estimates of the difficulty of the items ranged from -1.65 to 1.55 means that there is no problem that is too difficult or too easy, and is classified as a good item. MNSQ's INFIT value ranges from 0.86 -1.14 which means that the items match the Rasch model. Outfit value for each item ranged from -1.2 -1.7 (t ≤ 2.00) which means that all items were received.

This study proposes the hybrid substitution cryptography method followed by chaotic methods to improve the security of digital image transactions on the internet. The substitution method used is a hybrid of the modification of the Vigenère and Beaufort cipher algorithm. To do a hybrid, two random keys are used. The first random key is a matrix with 8-bits integer values, while the second random key is a matrix that contains binary values. The modulus operation is used in the main process of substitution methods. In this study, 24-bits true-color images were used as a dataset for the testing experiment. Measurement of encryption quality is measured by Entropy, MSE, PSNR, SSIM, UACI, and NPCR, whereas tic toc functions for measuring the computational time needed. To ensure the decryption process runs perfectly, measuring instruments such as SSIM, MSE, and PSNR are used to compare the decrypted image with the original image, the tic toc function is also used to measure computing performance. Based on the results of testing the quality of image encryption proved to have excellent results where the entropy value is very close to 8, the ideal NPCR and UACI values, as well as excellent visual values based on MSE, PSNR, and SSIM measurements. The image can also be decrypted perfectly with relatively fast computing time in the encryption and decryption process.

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Purpose: this study is to find out how the local strongman strategy in winning the candidate for the head of the village. Bumi Sari Village, Natar District, South Lampung Regency. Method: The researchers used the local strongman theory through an offensive and defensive strategy approach. Both of these strategies will be used to understand this phenomenon. The type of research used is qualitative research by conducting interviews with people involved in the election of the head of Bumi Sari Village. Result: The results of the election for the head of Bumisari Village in 2019 won Yosar Supriyono as the village head, Yosar Supriyono was re-elected as the head of the Bumisari village in 2019. Supri's victory could not be separated from the support of the local Strogman. The involvement of the local strongman in the village head election makes it interesting to see how the local strongman strategy in an effort to win Yosar in the village head election in Bumisari in 2019. Contribution: 1. Delegating a team of experts in the field of village politics to find out the vote map, 2.Forming groups of successful teams so that they can be closer and in direct contact at all levels.community activities. Keywords: 1. local strongman 2. offensive 3. defensive strategies

An atomic web service is not enough to meet complex user needs. This need can only be fulfilled by composing web services that perform operations automatically. The result of web service composition is a workflow. To the best knowledge of the authors, in the currently available methods existing a workflow output is not used to replace a workflow input. Also, web service backup is not provided. This can cause the transaction to stop because the web service that is being accessed cannot be invoked. Therefore, the authors propose a method that can utilize a workflow output to replace an input of another workflow and provide a web service backup. The supporting techniques used are tf-idf weighting and cosine similarity. The proposed method was applied to compose web services in a SaaS Business Intelligence application. The modules in Business intelligence are run using workflows that are composed based on the similarity between input parameters and output parameters required by the user with the web service metadata provided. The experimental results show that the proposed method can successfully produce workflows whose input can be replaced by other workflows and provide appropriate web service backup.