Has vs. might not have been?

Here’s the two sentences:

This has not always been the case.

This might not have always been the case.

Obviously, using “has” in the first and “have” in the second is correct. I know that. But, what is the rule that says that is it the case? The only different between the two is “might not” but I am just curious as to what rule established this usage.

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Is the i in this logo visible or how might I improve it? [on hold]

At school there is a room for people to create using things like 3D Printers, vinyl cutters, plotters, etc.

I made this logo, but I want someone more experienced to critique it. One problem I have with it is that when the logo is by itself, it looks like it’s missing a part on the right. I also don’t know whether to keep the “i” or not.enter image description here

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Is the i in this logo visible or how might I improve it?

At school there is a room for people to create using things like 3D Printers, vinyl cutters, plotters, etc.

I made this logo, but I want someone more experienced to critique it. One problem I have with it is that when the logo is by itself, it looks like it’s missing a part on the right. I also don’t know whether to keep the “i” or not.enter image description here

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Android Studio “Variable ‘example’ might not have been initialized” What do do now?

my problem is Android Studio says “Variable ‘example’ might not have been initialized”. This applies to these two:

private final BluetoothSocket bluetoothSocket;
private final BluetoothDevice bluetoothDevice;

and in line 57 the bluetoothDevice is red underlined and says “Cannot assign a value to final variable ‘bluetoothDevice'”

Hope someone can help 🙂

Here is my BT_Classic.java :

package com.car.bluetooth.bluetoothcar;

import androidx.appcompat.app.AppCompatActivity;

import android.app.ProgressDialog;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothSocket;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.ListView;

import java.io.IOException;
import java.util.ArrayList;
import java.util.Set;
import java.util.UUID;

public class BT_Classic extends AppCompatActivity {

private Button pairedButton;
private Button discoveredButton;
private Button btonButton;
private Button btoffButton;
private ProgressDialog progress;
ListView listView;
private final BluetoothSocket bluetoothSocket;
private final BluetoothDevice bluetoothDevice;

private final static UUID uuid = UUID.fromString("fc5ffc49-00e3-4c8b-9cf1-6b72aad1001a");

private ArrayList mDeviceList = new ArrayList();

BluetoothAdapter btAdapter = BluetoothAdapter.getDefaultAdapter();


private static final int REQUEST_ENABLED = 0;
private static final int REQUEST_DISCOVERABLE = 0;

private class ConnectingThread extends Thread {

    public ConnectingThread(BluetoothDevice device) {

        BluetoothSocket temp = null;
        bluetoothDevice = device;

        // Get a BluetoothSocket to connect with the given BluetoothDevice
        try {
            temp = bluetoothDevice.createRfcommSocketToServiceRecord(uuid);
        } catch (IOException e) {
        bluetoothSocket = temp;


    public void run() {
        // Cancel any discovery as it will slow down the connection

        try {
            // This will block until it succeeds in connecting to the device
            // through the bluetoothSocket or throws an exception
        } catch (IOException connectException) {
            try {
            } catch (IOException closeException) {

        // Code to manage the connection in a separate thread

    // Cancel an open connection and terminate the thread
    public void cancel() {
        try {
        } catch (IOException e) {


protected void onCreate(Bundle savedInstanceState) {

    pairedButton = (Button) findViewById(R.id.pairedButton);
    discoveredButton = (Button) findViewById(R.id.discoveredButton);
    btonButton = (Button) findViewById(R.id.btonButton);
    btoffButton = (Button) findViewById(R.id.btoffButton);

    listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        public void onItemClick(AdapterView parent, View view, int position, long id) {
            String  itemValue = (String) listView.getItemAtPosition(position);
            String MAC = itemValue.substring(itemValue.length() - 17);
            BluetoothDevice bluetoothDevice = btAdapter.getRemoteDevice(MAC);
            // Initiate a connection request in a separate thread
            ConnectingThread t = new ConnectingThread(bluetoothDevice);

    //Pairing Button

    pairedButton.setOnClickListener(new View.OnClickListener() {
        public void onClick(View v) {
            Set pairedDevices = btAdapter.getBondedDevices();

            ArrayList devices = new ArrayList();

            for (BluetoothDevice bt : pairedDevices){


            ArrayAdapter arrayAdapter = new ArrayAdapter(BT_Classic.this, android.R.layout.simple_list_item_1, devices);

    discoveredButton.setOnClickListener(new View.OnClickListener() {
        public void onClick(View v) {

                Intent bton = new Intent(BluetoothAdapter.ACTION_REQUEST_DISCOVERABLE);
                startActivityForResult(bton, REQUEST_DISCOVERABLE);


    btonButton.setOnClickListener(new View.OnClickListener() {
        public void onClick(View v) {
            Intent bton = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
            startActivityForResult(bton, REQUEST_ENABLED);

    btoffButton.setOnClickListener(new View.OnClickListener() {
        public void onClick(View v) {


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Is there a single word for doing something despite the fact that it might cause problems later?

Even better, if the word indicates that you’re the one who ultimately suffers.

Ex: I leave a suitcase in the middle of the hall, knowing someone might trip on it but ignoring that fact. Then I trip on it later on.

Or: I leave keys on a desk, though if I put them in the proper spot I won’t have to look for them later. Later on I can’t find them.

I’m thinking German might be a better bet for finding a single word, more specific to the outcome as well as the disregard for better judgement.

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What does this phrase (“..for who knows which ideas now considered …might one day upset the prevailing paradigm”) mean?

The following sentence is a GRE style text-completion sentence, where you must fill in each blank from only one of three enlisted options.

It is telling that some scientific ideas that were once (i) _______ have recently garnered (ii) _______ the intelligentsia, for who knows which ideas now considered (iii) _______ might one day upset the prevailing paradigms.

(i) forgotten

(ii) disapprobation from
currency amongst
scorn from

(iii) overtly elaborate
patently false
beyond reproach

The answers given are ridiculed, currency amongst and patently false respectively.

I am struggling to understand the part of the sentence after the comma

for who knows which ideas now considered (iii) _______ might one day upset the prevailing paradigms.

What does this mean? That there are ideas that sometime in the future will upset the prevailing, accepted view? How does this clue help to decide what answer goes in option (iii)? Without this, I’m also unable to answer the first two blanks.

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Why might a neural network consistently underestimate its target?

I have a neural network that is consistently underestimating the targets on the validation set, target set, and on the training set (by about the same amount as on the validation set and target set). In other words, the sum of the neural network regression outputs is something like 10% less than the sum of the target. Creating the neural network using many random seeds consistently leads to similar results (the neural networks are all biased in the same direction and by a similar amount).

The problem seems to be fairly robust to changes in important hyperparameters, including:
– early stopping
– learning rate schedule
– model complexity
– regularization (dropout, batch norm)

The problem is less severe for low-capacity neural networks.

Does anyone have any ideas as to why this persistent underestimation might be happening?

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Update-How might we perceive our relations with the environment?

With an excessively growing population, human might be increasingly conflicting with the environment. How might we perceive our relations with the environment? Our advancement in civilization might bring benefits to the environment?

Thoughts after more than half a year:
After watching Han Rosling Ted talk, I believe that population will stop growing with better development in less well-off countries.

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How might kinetosynthesizing “plants” look?

Suppose that there is a moon, orbiting a gas giant, and that gas giant is a rogue planet – it moves freely through the universe, unbound by the gravity of a star. This means that one, the moon will never see the light of day, and two, there will be no sun to warm it.

But say that the processes of volcanism, convection and tidal heating do give it warmth. In that case, the moon could, potentially, be habitable, assuming other figures, statistics and technicalities were also appropriate for habitability.

With no light – save for naturally occuring fires or volcanic eruptions – photosynthesis is impossible here. Chemosynthesis isn’t really possible except in special locations, so to have something roughly similar to plants, a new process must be devised.

We’ll call that process kinetosynthesis – a method of autotrophy not seen on Earth. While photosynthesizers use chloroplasts to strip electrons from substances as water, kinetosynthesizers use piezoelectric crystals in their cells, such as quartz, to do the same thing, but with mechanical stress replacing sunlight. I’m no chemist, so I’ll leave the process as vague as is for this question.

These kinetotrophic plants would likely have a number of energy sources, so as to exploit vacant niches; namely wind, rain, tides, sound and pure stress. If this sunless moon was volcanically active, wind and rain could be present – volcanic hotspots create contrasting hot and cold areas for the air to move between, and volcanoes play a part in Earth’s water cycle – were they in greater density, they could cause rain to occur.

One possible problem with kinetosynthesis is the lack of energy that can be obtained – but perhaps the lower gravity, plus an oxygen-rich atmosphere (Which could be boosted significantly once kinetotrophic “Embryophytes” evolved, which in turn would be fuelled by the high volcanic activity), would decrease the energy usage of various organ systems, combined with drastic tides and fast winds – would make it more plausible.

In the end, it’s fair to say that we really don’t know if kinetosynthesis would work. But, let’s just say that it is here. Finally, onto my question: If there were sessile, multicellular kinetoautotrophs, using piezoelectricity in the method described above, how would they be structured?

Let me explain a bit more. Earth plants, as we all know, have roots in the ground, a stem, and leaves. Stems are, in part, for growing taller than your peers, and thus get more light than them. How might kinetotrophs grow to recieve more energy than the surrounding ones? Leaves are for photosynthesis, mainly. Would kinetotrophs benefit from specialized kinetosynthesizing structures?

Obviously, a plant that got energy from the tides would look different to one that got energy from the wind, and one that fed on rain would differ from one that fed on sound. For your answers, you can select any of the energy sources (Wind, rain, tide, sound, stress).

If you consider this premise implausible, please say so. If you deem the question in need of editing, please say so too.

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What kind of cipher is this, and how might someone go about solving it?

Here’s the puzzle:

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