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v3.23.2

Summary of Significant Accounting Policies (Tables) | 12 Months Ended
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Apr. 30, 2023
Accounting Policies [Abstract] |
Schedule of Revenue Recognizes From Operating Lease Arrangements | The below table represents the total revenue recognized under ASC 606 and ASC 842 fiscal years ended April 30, 2023 and 2022: Schedule of Revenue Recognizes From Operating Lease Arrangements
|  | Fiscal year ended April 30, 2023 |  |  | Fiscal year ended April 30, 2022 |
|  | ASC 606 |  |  | ASC 842 |  |  | Total |  |  | ASC 606 |  |  | ASC 842 |  |  | Total |
|  | (in thousands) |  |  | (in thousands) |
Product Line: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
WAM-V |  | $ | 919 |  |  | $ | 667 |  |  | $ | 1,586 |  |  | $ | 401 |  |  | $ | — |  |  | $ | 401 |
Buoy |  |  | 269 |  |  |  | — |  |  |  | 269 |  |  |  | 379 |  |  |  | — |  |  |  | 379 |
Services |  |  | 877 |  |  |  | — |  |  |  | 877 |  |  |  | 979 |  |  |  | — |  |  |  | 979 |
Total |  | $ | 2,065 |  |  | $ | 667 |  |  | $ | 2,732 |  |  | $ | 1,759 |  |  | $ | — |  |  | $ | 1,759 |
Region: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
North and South America |  | $ | 1,812 |  |  | $ | 667 |  |  | $ | 2,479 |  |  | $ | 1,633 |  |  | $ | — |  |  | $ | 1,633 |
Europe |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 19 |  |  |  | — |  |  |  | 19 |
Asia and Australia |  |  | 253 |  |  |  | — |  |  |  | 253 |  |  |  | 107 |  |  |  | — |  |  |  | 107 |
Total |  | $ | 2,065 |  |  | $ | 667 |  |  | $ | 2,732 |  |  | $ | 1,759 |  |  | $ | — |  |  | $ | 1,759 |
Schedule of Cash and Cash Equivalents and Restricted Cash | Schedule of Cash and Cash Equivalents and Restricted Cash
|  | April 30, 2023 |  |  | April 30, 2022 |
|  | (in thousands) |
Checking and savings accounts |  | $ | 2,874 |  |  | $ | 1,815 |
Money market account |  |  | 4,009 |  |  |  | 6,070 |
Cash and cash equivalents |  | $ | 6,883 |  |  | $ | 7,885 |
Schedule of Cash and Cash Equivalents and Restricted Cash | The following table provides a reconciliation of cash, cash equivalents and restricted cash reported within the Consolidated Balance Sheets that total to the same amounts shown in the Consolidated Statements of Cash Flows. Schedule of Cash and Cash Equivalents and Restricted Cash
|  | April 30, 2023 |  |  | April 30, 2022 |
|  | (in thousands) |
Cash and cash equivalents |  | $ | 6,883 |  |  | $ | 7,885 |
Restricted cash- short term |  |  | 65 |  |  |  | 258 |
Restricted cash- long term |  |  | 155 |  |  |  | 219 |
Cash, cash equivalents, restricted cash and restricted cash equivalents |  | $ | 7,103 |  |  | $ | 8,362 |
Schedule of Investments and Unrealized Gains/Losses | The following table summarizes the Company’s short term investments as of April 30, 2023 and 2022: Schedule of Investments and Unrealized Gains/Losses
|  | April 30, 2023 |  |  | April 30, 2022 |
Category |  | Amortized Cost |  |  | Unrealized Gains (Losses) |  |  | Market Value |  |  | Amortized Cost |  |  | Unrealized Gains (Losses) |  |  | Market Value |
|  | (in thousands) |  |  |  |  |  |  |  |  |  |  |  |  |
Corporate Bonds |  | $ | 14,776 |  |  | $ | 100 |  |  | $ | 14,876 |  |  | $ | 37,777 |  |  | $ | 995 |  |  | $ | 38,772 |
Government Bonds & Notes |  | $ | 9,188 |  |  | $ | 33 |  |  | $ | 9,221 |  |  | $ | 9,076 |  |  | $ | (1,022 | ) |  | $ | 8,054 |
Government Agency |  | $ | 3,826 |  |  | $ | 25 |  |  | $ | 3,851 |  |  | $ | 2,531 |  |  | $ | (11 | ) |  | $ | 2,520 |
Total Short Term Investments |  | $ | 27,790 |  |  | $ | 158 |  |  | $ | 27,948 |  |  | $ | 49,384 |  |  | $ | (38 | ) |  | $ | 49,346 |
Schedule of Property, Plant and Equipment, Useful Life | Schedule of Property, Plant and Equipment, Useful Life
Description |  | Estimated useful life
Equipment |  | 5-7 years
Computer equipment & software |  | 3 years
Office furniture & fixtures |  | 3-7 years
Leasehold improvements |  | Shorter of the estimated useful life or lease term
Leased WAM-V assets |  | 10 years

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