kavalg

Thanks for the clarification.

My (possibly wrong) TLDR: TransMLA is a method to "compress" an already trained GQA model, with the additional option to further fine tune it. Shall make inference faster.

In the EU they use fertilizers and pesticides, but rarely use irrigation. However, pesticides are usually applied over the lifecycle of the plants. For fertilizer, there is some value to apply it on time, because it tends to migrate with water and applying now vs a month ago is not equivalent.

I am not sure that I understand your question correctly, but given more precise sunflower density estimation, the farmer has three options:

1. Plow the field and seed again (same or different variety or grain). This is a very crude measure, but it is sometimes the right thing to do, because as I said most of the expenses have not been realized yet (fertilizer, pesticide, fuel, payroll, paying rent for the land). It is also a time critical decision, because the window of opportunity for plowing and reseeding is not very wide.

2. Accept the lower yield if it is within a reasonable margin (e.g. comparable to the expenses to plow and reseed).

3. Do partial reseeding over the existing plants (without plowing). This is an emerging strategy with the proliferation of smart seeders, but it requires a precise seeding map to be created beforehand (i.e. based on the density estimate). As an advantage, you spare the expenses for seeds and plowing, however there is some disadvantage as well, due to the different rate of development of the newly seeded plants. Farmers usually need plants to be ready for harvest at the same time, otherwise the quality of the grains suffers and hence the selling price is lower.

In addition to these points, having precise density information after germination helps with the identification of problems, such as seeder malfunction (e.g. nozzles getting clogged), seed quality and meteo data (e.g. too much rain, low temperatures etc).

> Undershooting means paying for someone's product to make up for the difference

Indeed. Making up the difference can easily eat most of the farmer's profits. I guess it is even more pronounced for berries when compared to grains, because they cannot be stored for so long.

It is possible. However, getting accurate yield data requires a "smart" harvester that can produce yield maps. Many modern harvesters are equipped with GPS and various sensors, so it is possible. However, farmers are really slow to replace old equipment if it works fine. I guess there are some retrofit solutions for yield mapping, but I haven't investigated their affordability and penetration into the (EU) farming landscape yet. Additionally, there are other interesting parameters apart from the harvested quantity that can be captured (e.g. the quality of the grain itself, such as size, composition, humidity etc).

Interesting. Thanks!

I am working on the sunflower plant density estimation problem. The goal is to be able to estimate the germination rate as early as possible. Farmers benefit from such information, because:

- there are lots of expenses still to be made (fertilizer, pesticide, salaries), which may not be worth it if germination is under certain threshold

- if detected early, there is still time to plant another grain or to fill up the missing plants (requires precision seeders and seeding maps)

- is a very good proxy for yield estimation (farmers often trade futures even before they have harvested)

For the purpose I have created a dataset (a collaboration between my employer and Sofia University) and published it in order to enable scientific collaboration with other interested parties. Still working on the dataset annotations.

https://huggingface.co/datasets/su-fmi/sunflower-density-est...

Yeah, the taste matters if you are going to eat it for 2 weeks :). You will probably still hate it after the first week, but it is just one week of misery instead of two. I did some fasting in the past, leaving only water, tea (no sugar) and peeled apples in my diet. Had to do it for 2 weeks, but only made it to the 11th day. The issue with that one was the low calories, which doesn't correspond well with active work (I did not plan properly to take the second week off). Nevertheless, it helped solve the colitis issue, with which I'd been struggling for a few months. An interesting observation was that up to say day 4 or 5 you actually have more energy and sleep less. But after that it was a bit of a struggle to retain the same levels of energy and be productive at work.

Yes, that is a major factor too as well as antibiotics or the combination of the two.

Indeed. I am just a bit concerned that the subjects were to return to their "normal" diet after the experiment, which probably was the reason to get this condition in the first place. In a next study it would be interesting to look closer into the functioning of related organs, such as liver and gallbladder (vesica fellea). E.g. did subjects have any biliary sand issues. Correlation with potable water used by the subjects would also be interesting, especially things like mineral composition, pH, organic contaminants (e.g. microplastics) as well as microbial content.

It looks it contains mostly amino acids and vitamins, usually found in other fitness supplements. Is there any "secret sauce" that I am missing?

The abstract doesn't mention that accuracy is better than GPS, but by INS (inertial).

Wouldn't that be prohibitive energy-wise? AFAIK satellites are not abundant in electrical power.

The last time trading oil with other currencies was on the table, a couple of dictators lost their heads.

Are you sure? Maybe the rich just want to buy shares back at a favorable price. I can't help wondering how much cash they are holding now.

And license: Creative Commons Attribution, Non Commercial

In my experience, military aircrafts are visible in flightradar most of the time. However, if they are flying in a group (e.g. choppers), usually only one of them is visible.

Just FYI, it turned out to be a bad connection between the controler PCB and the NTC temperature sensor that measures the condensation temperature at the plate heat exchanger.

Thanks for the info! Now it is much easier to understand your concerns. It is a rather big installation that you have here, in the range around 100kW (if both space heating and DHW are considered). Such systems (aka chillers) are usually installed away from buildings or on the rooftop if local regulations allow it.

Wow! Your notes look like a treasure trove on the topic(s)!. I will definitely read them. Ironically, my heat pump just failed yesterday and now I am going through the service manual, so the resistance heater proponents may have some merit :)

You can buy smaller ones. Domestic heat pumps usually start around 6-8 kW for single phase ones and go up to ~20kw for 3-phase units. Keep in mind that these values are the peak power of the heat pump, which you would rarely use. Modern units have inverter motor driven compressors, which can modulate their power output in the range 25%-100%. 100% is not a happy place for the heat pump if it is cold (and humid) outside, because it will quickly accumulate ice on the outdoor unit and start doing many defrost cycles per hour, which lowers the COP (efficiency).

With respect to the duty cycle, obviously if you have solar power, you would prefer to use it predominantly and only add up some extra power from the grid when needed. This is the essence of the sizing problem, because that leads you to 2-3x power overprovisioning and the need for heat/cold storage. Heat storage can be two types - DHW and space heating. Space heating is the easiest to estimate. You need to know your house's heat loss (either by specification or just figure it out empirically if you have already lived in it). DHW storage is more difficult to estimate, because it depends on the usage (e.g. how many showers per day). Cold storage is the most problematic, because the fluid needs to be at least 16C or lower to do useful cooling work, however you cannot go much lower than 7C unless you are using propylene glycol (expensive) and even then your indoor units may start to freeze (I am not even mentioning indoor humidity management and dew points).

Lately, the industry has been exploring PCMs (phase change materials). The idea is to store heat/cold not as sensible heat, but as latent heat of the phase change. In practice the substances used are either salts (efficient, but corrosive to the storage tank) or paraffins (more expensive, less efficient, but still viable). These come rated at a specific temperature, but usually have some hysteresis/drift and other issues. I guess you are now feeling a bit frustrated from the engineering complexity :). If batteries were cheap, long lasting and environmentally friendly, this complexity would not be needed. However, I really doubt it that in the foreseeable future batteries will beat heat storage. Given that most of our domestic energy use is space heating/cooling and DHW, I think that PCMs may actually have some moat. There are already offerings on the market, but IMHO they are still not very compelling. What I see lacking is some integrated offering, that would take into account the PV schedule and also grid prices. One a side not, batteries still have an advantage if you can sell back to the grid at a high premium or if you need to e.g. charge your car in the night. So these technologies may be complementary, rather than competitive.

A very big factor is climate. Just to give you an example, I live in the mountain with a colder climate. Cold water from the faucet is around 10C. I rarely need cooling if at all, but I need space heating around 8-9 months during the year. Just 300 km south and by the sea (Greece), cold water from the faucet is around 20-25C, you need 4-5 months of cooling and only ~4 months of heating. Some countries, such as UK have very moderate climate without extremes and things are more predictable. Where I live, we get -15C in the winter and 38C in the summer.

Noise could be a problem, but it is often the result of a bad installation. I'd be curious how much was the quote for the heat pump vs the oil heater.

USD 4000 will buy you something like 12 - 16Kw R32 heat pump. If you have enough roof area to install 50kW PVs then you must live in a mansion :). Another thing is that heat pump installations are usually dual purpose (space heating/cooling and DHW).

That is a good question. The usable life of a combined heat pump (space heating/cooling + DHW) is somewhere between 10-15 years. For the ones, dedicated to DHW, I cannot really tell, but I would expect it to be longer, because they are usually less heavily loaded. Then the answer of your question will depend on the price of installation (e.g. heat pump vs 3 x extra PVs), local climate (affects efficiency) and price of electricity. Heat pumps don't work well in very cold climates, but for most US/EU cities they will work fine. For very hot climates it may be better to use solar water heaters, although for commercial installations there is the option to use the exhaust heat from cooling to heat DHW (it is essentially free energy).

As hot as possible is not the way to go. Heat pump COP will degrade dramatically if you try to boil the water. It is not even possible with the popular refrigerants (R32, R410a and even R143a), because they will exceed their critical temperature. If you cannot afford the space for a bigger DHW tank, then there are two options:

1. Consider PCM heat storage (still relatively new technology, but works well with heat pumps)

2. Maybe the problem shall be solved at the building level, not individual apartments.

True, but you never need 200F for DHW. This is even dangerous (scalding) and harmful to the piping. Typical temperatures for heat pump derived DHW are around 120F (45-50C), with some (bi)weekly cycles to avoid legionella build up at 150F(65C). Your statement is generally true, because a heating installation that is optimized for heat pump works at 85-100F, however in practice not many installations in old buildings are like that.

Why are people even considering an electric heating element, when you can get at least 2-3 times the efficiency of a DHW heat pump that would probably cost you ~ $4000. In my experience, I have found that for PV panels it is often the roof area / orientation that limits the energy capacity that you can install. Installing a heat pump instead of resistive heater can effectively reduce this 2-3 times.

Yes, heating DHW with a heat pump is not that trivial. There could be problems when the tap water is hard (limescale problems in heat exchangers), you often need 2-3 times larger tank in order to cover the daily cycle, but still looks more efficient than a big battery and an electric heater.

PS: I've accumulated lots of knowledge on the topic. DM me if you are interested in exchanging on this.

Great comments from both of you. I will also add the (unsupportive) environment and uncertainty for the future as major factors IMHO.

One should also consider the "outside" environment. We jumped from covid right into war without a break in between and now we are being told that we will be replaced by AI, while expecting the stock market to crash and increase unemployment. Ah and also the inflation (wage reduction) that has been going on for the last five years and doesn't show a sign of stopping.

> Does this reveal an inherent tribalism in our thinking?

Yes, it does. We are humans too, not some upper cast of society that is permanently immune to prejudice, emotions and media influence reinforcing the former two. Unfortunately, it is not only Romania that is straying away from democracy. Bulgaria, another EU member state, and by coincidence (or not) a neighbor to Romania, has also been degrading significantly in this regard. To quote a couple of examples:

- A referendum on the topic of delaying Bulgaria's entry into the Euro zone (replacing national currency with EUR) was not allowed to take place by the parliament and subsequently the constitutional court (with really hard to understand and controversial argumentation).

- There were lots of violations during the last elections that were investigated selectively and following a questionable and non-transparent process

- Protesters being detained for a month for throwing eggs on a building - a highly disproportional measure, given the severity of the violation.