Saturday, November 15, 2025

What are the ways a person can collect evidence of wrong doing of his colleague.. in an academic setting

When dealing with suspected wrongdoing by a colleague—especially in an academic setting—you must avoid illegal, invasive, or unethical surveillance. But there are legitimate, safe, and institutionally appropriate ways to document concerns.

Here are legal, ethical, and academically accepted methods:


1. Keep a Detailed, Dated Written Record

Maintain a journal or log that includes:

  • What happened

  • When it happened (date/time)

  • Where it happened

  • Who else was present

  • Exact words/actions if possible

This becomes valuable evidence because it establishes a timeline and pattern of behavior.


2. Preserve Written Communication

If wrongdoing appears in:

  • Emails

  • Messages

  • Official memos

  • Collaboration tools (Slack, Teams, LMS, GitHub comments)

…you can keep copies.
Do NOT intercept private communication — only save things you legally received.


3. Save Work-Related Artifacts

In academics, wrongdoing often appears in:

  • Plagiarized assignments

  • Fabricated lab data

  • Manipulated research results

  • Improper grading behavior

  • Misuse of institutional resources

You may store:

  • Copies of submitted work

  • Screenshots of shared documents

  • Version histories (Google Docs, Git, Overleaf)

  • Lab notebook discrepancies

Again: only what you legitimately have access to as part of your job or role.


4. Collect Witness Statements (Informally or Formally)

If others have seen the same behavior:

  • Ask them to write down what they observed

  • Or ask them if they’re willing to speak to an official

  • Never pressure or coordinate stories

Multiple independent accounts strengthen credibility.


5. Follow Internal Academic Procedures

Universities have structures created exactly for this:

  • Academic Integrity officer

  • Ombudsperson

  • Department chair

  • Ethics committee

  • HR office (for staff)

  • Mentor or advisor (for students)

They may also guide you on what types of information you may or may not collect legally.


6. Preserve Physical Evidence (If Relevant)

Examples:

  • Altered documents

  • Suspicious lab equipment logs

  • Hard copies with forged signatures

  • Improperly accessed files (if you find signs, not by snooping)

Always keep originals if possible; otherwise store copies.


⚠️ What You Should Not Do

To protect yourself legally:

❌ Secret audio/video recording (illegal in many jurisdictions without consent)
❌ Accessing their email or files without permission
❌ Installing monitoring software or cameras
❌ Hacking, intercepting network traffic
❌ Pretending to be someone else to “catch” them
❌ Gathering information in private spaces (office drawers, personal devices)

These can backfire and lead to serious consequences for you.


A Safe, Effective Approach

If the wrongdoing could impact academics (plagiarism, fraud, harassment, sabotage, etc.):

  1. Write down everything clearly

  2. Keep any evidence you already legally have

  3. Check your institution’s official reporting procedure

  4. Submit the evidence only to trusted authorities


If you want, you can tell me:

  • the type of wrongdoing (plagiarism? harassment? data fraud? misuse of power?)

  • whether you are a student, TA, faculty, or staff

…and I can suggest the exact appropriate steps and what kind of evidence is acceptable in that specific scenario.

Tuesday, November 11, 2025

Region Growing-stopping rule

Descriptors alone can yield misleading results if connectivity properties are not used in the region growing process. 
For example: Visualize a random arrangement of pixels that have three distinct intensity values.

Grouping pixels with the same intensity values to form a region, without paying attention to connectivity, would yield a segmentation fault that is meaning less in the context of this discussion.

Another problem in region growing is the formulation of a stopping rule: 
Region growing has to stop when no more pixels satisfy the criteria for inclusion in that region.

Criteria such as intensity value, texture and color are local in nature and do not take into account the history of region growth.
Additional criteria that can increase the power of a region-growing algorithm utilize the concept of size, likeness between a candidate pixel and the pixels grown so far(such as comparison of the intensity of a candidate and the average intensity of the grown region) and the shape of the region being grown.

Let f(x,y) denote an input image; S(x,y) denote a seed array containing 1's at the locations of seed points and 0's elsewhere; Q denote a predicate to be applied at each location(x,y). Arrays f and S are assumed to be of the same size.

1. Find all connected components in S(x,y) and reduce each connected component to one pixel; label all such pixels found as 1. All other pixels in S are labeled 0.

2. Form an image fQ such that, at each point (x,y), fQ(x,y)=1 if the input image satisfies a given predicate, Q, at those coordinates, and fQ(x,y)=0otherwise.

3. Let gg be an image formed by appending to each seed point in S all the 1-valued points in fQ that are 8-connected to that seed point.

4. Label each connected component in g with a different region label (e.g., integers or letters). This is the segmented image obtained by region growing.


Segmentation by region growing

Computer Vision- Segmentation by Region Growing and by Region Splitting and Merging

 Objective: Partition an image into regions

Region Growing- As the name implies, Region Growing is a procedure that groups pixels or subregions into larger regions based on predefined criteria for growth.

Basic Approach: Start with a set of "seed" points, and from these grow regions by appending to each seed those neighboring pixels that have predefined properties similar to the seed(such as ranges of intensity or color)

How many seeds? Which ones?

The procedure is to compute at every pixel the same set of properties that ultimately will be used to assign pixels to regions during the growing process. If the result of these computations shows clusters of values, pixels whose properties place them near the centroid of these clusters can be used as seeds.

Example: Land use satellite imagery

We need to do region analysis with a set of descriptors based on intensity levels and spatial properties(such as moments or texture). Descriptors alone can yield misleading results if connectivity properties are not used in the region growing process.

Thursday, November 6, 2025

Create Data Preservation Library

Question: Can I create a library that preserves data before its deleted/discarded from applications like in python app if list.clear() is called I will modify behavior of clear to store the cleared data locally until such time that it can be backed up in a remote server. So that applications don't lose data. 

That’s an excellent and very advanced idea — and yes, it’s definitely possible to build a Python library that intercepts data-deletion or mutation calls (like list.clear(), dict.pop(), del, etc.) and preserves data before it’s lost.

Let’s break it down step-by-step so you understand what’s involved.


🧩 Core Concept

You can override or wrap built-in data structures (like list, dict, set, etc.) with custom subclasses that:

  • Intercept destructive operations (clear, pop, remove, slicing assignments, etc.)

  • Log or copy the data before the operation

  • Store it temporarily in a local cache or file

  • Optionally send it later to a backup/remote server


⚙️ Example: SafeList

Here’s a minimal prototype:

import json
from datetime import datetime

class SafeList(list):
    def __init__(self, *args, backup_handler=None, **kwargs):
        super().__init__(*args, **kwargs)
        self.backup_handler = backup_handler or self.default_backup

    def default_backup(self, data):
        # Simple file-based backup
        with open("backup_log.jsonl", "a") as f:
            json.dump({
                "timestamp": datetime.now().isoformat(),
                "data": data
            }, f)
            f.write("\n")

    def clear(self):
        if self:
            self.backup_handler(list(self))
        super().clear()

    def pop(self, index=-1):
        value = super().pop(index)
        self.backup_handler([value])
        return value

    def __delitem__(self, index):
        value = self[index]
        self.backup_handler([value])
        super().__delitem__(index)

Usage:

x = SafeList([1, 2, 3, 4])
x.clear()  # backup before clearing

This will save the data to a file before deletion.


🧠 Extending the Concept

You can generalize this into a library that:

  • Wraps multiple container types (SafeDict, SafeSet, etc.)

  • Hooks into all destructive methods

  • Supports pluggable backup handlers (e.g. local cache, SQLite, HTTP endpoint)

  • Optionally tracks who triggered the deletion (stack trace)

  • Provides automatic periodic upload of backup data to a remote service


🔥 Advanced Ideas

  1. Monkey patch built-ins (⚠ risky, but doable):

    import builtins
    builtins.list = SafeList
    

    → All new lists created in the program become “safe.”

    But this can break libraries that expect a real list, so it should be optional or done via context managers.

  2. Proxy Layer (non-invasive)
    Wrap existing objects dynamically:

    safe_obj = make_safe(existing_list)
    

    where make_safe() detects the type and returns the corresponding safe wrapper.

  3. Transparent Auto-Backup Middleware
    Hook into serialization layers or database ORMs to back up critical structures before deletion.

  4. Undo/Versioning
    Each change could generate a diff or a version history entry so that you can roll back changes — similar to a mini Git for runtime data.


🚧 Design Challenges

  • You must handle nested data (list of dicts, dict of lists, etc.)

  • Performance overhead can be significant

  • Need to decide when to purge backups

  • Multithreading or multiprocessing synchronization for data safety


🪄 Prototype Architecture for Your Library

safe_data/
├── __init__.py
├── base.py          # Base class for safe containers
├── safe_list.py     # Implements SafeList
├── safe_dict.py     # Implements SafeDict
├── backup.py        # Backup handler (local/remote)
├── scheduler.py     # Handles periodic backup flushes
└── config.py        # Configurations (e.g. backup paths, thresholds)

Would you like me to show you how to design this as a Python package (with modules, classes, and a pluggable backup system)?
That would make it easy to install and import as import safe_data and wrap any object safely.