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question:In Java, say you have a class that wraps an `ArrayList` (or any collection) of objects. How would you return one of those objects such that the caller will not see any future changes to the object made in the ArrayList? i.e. you want to return a deep copy of the object, but you don't know if it is cloneable.

answer:A straightforward way to return a deep copy of an object without knowing whether it's cloneable is to serialize the object into a byte stream then deserialize it back into a new object. This process completely detaches the new object and the original one. Here is an example alone with necessary exception handling:```javaimport java.io.*;public class DeepCopier { public static Object deepCopy(Object original) { Object deepCopy = null; try { ByteArrayOutputStream byteOutputStream = new ByteArrayOutputStream(); ObjectOutputStream objOutputStream = new ObjectOutputStream(byteOutputStream); objOutputStream.writeObject(original); objOutputStream.flush(); ObjectInputStream objInputStream = new ObjectInputStream( new ByteArrayInputStream(byteOutputStream.toByteArray())); deepCopy = objInputStream.readObject(); } catch (IOException | ClassNotFoundException e) { e.printStackTrace(); } return deepCopy; }}```Note that this method requires the class of original, and any classes that it refers to, must implement the Serializable interface.If we apply this method to the example of the ArrayList, where you want to return a copy of the object:```javapublic class ObjectWrapper { private ArrayList<Object> objectsList; // .... other methods .... public Object getObject(int index) { Object obj = objectsList.get(index); return DeepCopier.deepCopy(obj); }}```This way, the caller of `getObject()` will receive a deep copy of the original object, so any further modifications to the original object in the ArrayList will not affect the copy.

question:The equation x^y=y^x has positive integral solutions of (2,4), (4,2) and (k,k) for all k &gt; 0. Define a function f(n) as the count of integral values 0 &lt; x,y leq n^2-n that satisfy the congruence relation x^yequiv y^x pmod n. For instance, f(5)=104 and f(97)=1614336. Now, consider a function S(M,N) which is the summation of f(p) over all prime numbers p in the range Mle ple N. Given that S(1,10^2)=7381000 and S(1,10^5) equiv 701331986 pmod{993353399}, your task is to determine the value of S(10^{16}, 10^{16}+10^6), providing your answer modulo 993353399.

answer:Let's break this problem down:1. The congruence relation x^y equiv y^x mod n looks similar to the original equation x^y = y^x. However, mod n restricts the solutions to a finite set that depends on n. 2. Function f(n) is the count of solutions in a certain range. This implies, it is feasible to compute f(n) in a brute-force manner for small n, but for larger n we need a more efficient approach. 3. Function S(M, N) is the sum of f(p) over all primes p in the interval (M,N). This suggests that we need some way to efficiently generate all primes in a range, and then compute f(p) for each. 4. The primary task is to find S(10^{16}, 10^{16}+10^6) mod{993353399}. Given the magnitude of these numbers, it's clear that a brute-force solution isn't feasible. We'll need to look for some kind of pattern or mathematical formula.Insight: x^y equiv y^x mod p where p is a prime. Now, from Fermat's little theorem, we have x^{p-1} equiv 1 mod p for all x not divisible by p. Re-writing the given congruence, we get x^{y}*(y^{x} mod p) = 0. Since y and x can't be p(divisible by p) because 0 < x, y leq p^2 - p, we must have y^{x} mod p = 0. The equation will then only hold where y is divisible by p. Consider p^2-p = p*(p-1). All solutions for y, provided that x^p equiv 0 mod p, will be of the form p, 2p, ..., (p-1)p. Hence, there are p-1 solutions for each x which will give a total of (p-1)^2 solutions.The python code with this optimization will be:```pythondef S(M, N): primes = generate_primes(M, N) # function to generate primes in range s = sum([(p-1)2 for p in primes]) return s % 993353399print(S(1016, 1016 + 106))```Note that we've reduced the problem essentially to needing a function `generate_primes(M, N)` that generates all primes in the range (M, N). It is a common task and can be accomplished by different algorithms like Sieve of Eratosthenes, Segmented Sieve, etc. which are not shown here.Remember the actual calculation of S(10^{16}, 10^{16}+10^6) can be very time and resource intensive even with the efficient approach. It's a large scale computation problem.

question:You are presented with multiple paper abstracts, alongside the associated literature review and chapter titles. Given the provided information, you are going to do a literature review. Please generate a coherent literature review that synthesizes the content, draws connections between different works, highlights major findings, and identifies any gaps in the existing research.Literature Review Title: A Survey on Secure Data Analytics in Edge Computing Chapter Title: A. Open Issues 1. Abstract of Cited Paper (BIB001): Internet of Things (IoTs) has emerged to motivate various intelligent applications based on the data collected by various “things.” Cloud computing plays an important role for big data processing by providing data computing and processing services. However, cloud service providers may invade data privacy and provide inaccurate data processing results to users, and thus cannot be fully trusted. On the other hand, limited by computation resources and capabilities, cloud users mostly cannot independently process big data and perform verification on the correctness of data processing. This raises a special challenge on cloud computing verification, especially when user data are stored at the cloud in an encrypted form and processed for satisfying the requests raised in different contexts. But the current literature still lacks serious studies on this research issue. In this paper, we propose a context-aware verifiable computing scheme based on full homomorphic encryption by deploying an auditing protocol to verify the correctness of the encrypted data processing result. We design four optional auditing protocols to satisfy different security requirements. Their performance is evaluated and compared through performance analysis, algorithm implementation, and system simulation. The results show the effectiveness and efficiency of our designs. The pros and cons of all protocols are also analyzed and discussed based on rigorous comparison. 2. Abstract of Cited Paper (BIB002): Abstract Social-Internet of Things (S-IoT) fortifies the relationship between computing entities for efficient utilization of resources. S-IoT accentuates on building convivial circles between the devices, which sanction sharing of information without compromising own performance. Trust and privacy are the two factors responsible for the maintenance of these social circles. Trust establishes faith between the entities and privacy supports abstraction of device information. There exist a plethora of approaches, which fixate on trust and privacy in social networks. However, the subsisting solutions rely on a trust scoring system and utilize a single centralized server for these calculations. Such scoring systems are manipulable by eavesdroppers, which engender erroneous reputation leading to high trust values. Considering the desideratum of an efficient trust and privacy-preserving solution, this paper proposes a novel solution in the form of fission computing. The proposed approach relies on the edge-crowd integration for maintenance of trust and preservation of privacy rules in S-IoT. The proposed solution uses crowdsources as mini-edge servers and entropy modeling for defining trust between the entities. Fission managers are responsible for maintaining the privacy rules, which operate for every S-IoT application. The proposed approach is analyzed through numerical simulations by using a safe network as a performance benchmark. Further, the article presents a case study on the detection of fake news sources in S-IoT as an application of the proposed approach. 3. Abstract of Cited Paper (BIB003): Mobile crowdsensing (MCS) has gained popularity for its potential to leverage individual mobile devices to sense, collect, and analyze data instead of deploying sensors. As the sensing data become increasingly fine-grained and complicated, there is a tendency to enhance MCS with the edge computing paradigm to reduce time delays and high bandwidth costs. The sensing data may reveal personal information, and thus it is of great significance to preserve the privacy of the participants. However, preserving privacy may hinder the process of handling malicious participants. In this paper, we propose two privacy preserving reputation management schemes for edge computing enhanced MCS to simultaneously preserve privacy and deal with malicious participants. In the basic scheme, a novel reputation value updating method is designed based on the deviations of the encrypted sensing data from the final aggregating result. The basic scheme is efficient at the expense of revealing the deviation value of each participant to the reputation manager. To conquer this drawback, we propose an advanced scheme by updating the reputation values utilizing the rank of deviations. Extensive experiments demonstrate that both these two schemes have high cost efficiency and are effective to deal with malicious participants. 4. Abstract of Cited Paper (BIB004): Abstract In recent years, cloud computing has become the most popular and promising service platform. A cloud user can outsource its heavy computation overhead to a cloud service provider (CSP) and let the CSP make the computation instead. In order to guarantee the correctness of the outsourced processing (e.g., machine learning and data mining), a proof should be provided by the CSP in order to make sure that the processing is carried out properly. On the other hand, from the security and privacy points of view, users will always encrypt their sensitive data first before they are outsourced to the CSP rather than sending the raw data directly. However, processing and verifying of encrypted data computation has always been a challenging problem. Homomorphic Encryption (HE) has been proposed to tackle this task on computations over encrypted data and ensure the confidentiality of the data. However, original HE cannot provide an efficient approach to verify the correctness of computation over encrypted data that is processed by CSP. In this paper, we propose a verifiable outsourced computation scheme over encrypted data with the help of fully homomorphic encryption and polynomial factorization algorithm. Our scheme protects user data security in outsourced processing and allows public verification on the computation result processed by CSP with zero knowledge. We then prove the security of our scheme and analyze its performance by comparing it with some latest related works. Performances analysis shows that our scheme reduces the overload of both the cloud users and the verifier.Literature Review:

answer:Based on the analysis and comparison on the existing works in Section V, we outline several open issues on secure data analytics in edge computing as follows. First of all, how to balance security and efficiency is still an open problem. From Table IV , we can observe that most works need user devices or edge nodes to perform some complex operations, which incurs high computation cost. In fact, some IoT applications in edge computing have a high demand on real-time response. The complex computation obviously impacts efficiency, especially for resource-constrained user devices. Therefore, making a tradeoff between security and efficiency becomes necessary in many practical situations. Second, the trustworthiness of networked devices in highly distributed network still need further researches. Though there are a few studies BIB003 , BIB001 , BIB004 on trustworthiness of networked devices, they still have some disadvantages. For example, the works in BIB003 and BIB004 consider only single application scenario and the study in BIB001 does not support mobility and scalability. However, device trustworthiness is an important demand to ensure the QoS of edge nodes and prevent a device from malfunction. Thus, an effective trust model for edge computing should be proposed. Third, UP is ignored in all reviewed works. However, it is very necessary to protect UP in edge computing. Since edge computing is designed specifically for IoT applications, the collected data contain user behavior information and living habit information. An eavesdropper or an edge node could easily obtain usage patterns even if data are encrypted before uploading to an edge server. For example, an eavesdropper can predict when a user is at home through the changes of the readings of a smart meter. Fourth, the literature still lacks an effective solution to verify the correctness of data computation when utilizing edge nodes to do data analytics. The correctness of calculation remains high importance in outsourced data analytics BIB005 , BIB002 . In edge computing, neither cloud servers nor edge nodes can be fully trusted, which makes it hard to ensure the correctness of data computation, processing and analytics. If there is no security solution to guarantee the above correctness, end users will be reluctant to use the services provided by edge computing. Fifth, mobility and scalability of mobile devices cannot be well supported in the current literature. Most existing works neglect the mobility and scalability of user devices when designing security schemes for edge computing. However, user devices and edge nodes might frequently migrate from one place to another. At the same time, user devices could quickly join or leave an edge network. Thus, a security scheme should support mobility and scalability in the context of edge computing, however, this is still an open issue.

question:You will be shown an abstract from a biomedical research paper. Given this abstract, your task is to extract all unique entities of the following types: ["Protein", "Chemical"].Please return the output as a JSON object of the format: {"Chemical" : ["Dexamethasone", ...], "Protein" : ["BRCA-1", ...]}. The keys should be entity types and values should be lists of extracted entities belonging to the corresponding type. If you cannot find entities belonging to a specific type, the value should be [].Only output the JSON object and do not include any additional text.Abstract:Complexities of androgen action.Androgens mediate a wide range of processes during embryogenesis and in the adult. In mammals, the principal androgens are testosterone and its 5alpha-reduced metabolite, 5alpha-dihydrotestosterone (DHT). Although these androgenic hormones are diverse in character, it is believed that their effects are mediated via the protein products of a single androgen receptor gene encoded on the X-chromosome. A great deal of information has now accumulated pertaining to the mechanisms by which nuclear receptors, such as the androgen receptor, modulate the activity of responsive genes. The studies have demonstrated the participation of a number of ancillary proteins in modulating activation or repression by nuclear receptors. In addition to studies focused on the mechanisms of nuclear receptor function, additional work has illuminated the mechanism by which androgens are metabolized in selected tissues. This information provides a perspective on the number of levels of complexity by which differential gene regulation by androgens may occur in different tissues and in different cell types.

answer:{"Chemical": ["androgens", "5alpha-dihydrotestosterone", "DHT", "androgen", "Androgens", "testosterone"], "Protein": ["nuclear receptors", "androgen receptor", "nuclear receptor"]}

question:You will be presented a sentence from biomedical research text. Extract all terms that correspond to chemical entities of biological interest (ChEBI).Return your identified terms in a JSON array, formatted like this: ["Entity1", "Entity2", ...].If no such entities are detected, respond by providing an empty JSON array [].Biomedical context:These14sequencesalsorevealedonecDNAwherethepoly(A)tailwasadded27bpbeforethestopcodon,andanotherwhereanintronwassplicedoutofthe3'UTR,contrarytotheconventionalstereotypeofolfactoryreceptorgenestructure.

answer:["A"]

question:What steps are required to implement Redshift Spectrum tables with Terraform and SerDe?

answer:Here are the steps to implement Redshift Spectrum tables with Terraform and SerDe:1. Install Terraform: The first thing needed to start with Terraform is to install its latest version. Terraform is available for download on macOS, Linux and Windows.2. AWS Configuration: You will need to set up your AWS credentials. You can set up your AWS access keys directly into your .tf files but this method is not recommended for security reasons. It's better to configure your credentials using the AWS CLI `aws configure`.3. Create a Terraform Project: Start up by creating a directory where your Terraform files will live.4. Writing and Configuring the Terraform files: So suppose we are creating an Amazon Redshift cluster and defining a Redshift Spectrum table. We'll need to use `aws_redshift_cluster` resource and `aws_glue_catalog_table` resource in our Terraform script. It might look something similar to:```resource "aws_redshift_cluster" "default" { // Your Redshift configuration here.}resource "aws_glue_catalog_table" "example" { name = "example" database_name = aws_glue_catalog_database.example.name table_type = "EXTERNAL_TABLE" // This is where you mention your SerDe. parameters = { EXTERNAL = "TRUE" "serialization.format" = "1" } storage_descriptor { // Your Storage description here like Location, Input format etc. }}```Remember to replace appropriate values and properties in the script.5. Initialize Terraform: In your terminal, cd into the directory with your .tf files and run the `terraform init` command. This will initialize Terraform in your directory.6. Plan and Apply: See what Terraform plans on doing with the `terraform plan` command and then apply those changes with `terraform apply`7. Verify: Login to the AWS Console to verify if changes have been made.This is a basic implementation of Terraform, AWS Redshift and Spectrum. Remember to adapt according to your use case.

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