Navy Proficiency Badges
2nd Class
海軍優等章
Here are some photos of the 2nd Class Navy Proficiency badges. There are 10 different
badges, according to Peterson. As you can see, I do not have an example for each one, so if
anyone can help with a photo, I'd appreciate it.

The title of each badge is that provided by Peterson. In parentheses I have put the English
translations I found in a Japanese source. That source called the 2nd Class badges
'Superior Badges' and the 1st Class badges 'Superior Ensigns.' The English titles (names)
are somewhat different, too, and some may be more accurate than Peterson's choices.
Torpedo Firing Proficiency Badge (Torpedo Shooting Superior Badge)
魚形水雷準手優等章
Instituted on September 8, 1911 (Meiji 44)
Notice of name change on February 23, 1929 (Showa 4)
'The full word for torpedo will be used.'
(The original name used a two-kanji contraction. The full word has four kanji.
No change in the English translation.)

The test for this badge mainly consisted of the actual firing of the torpedo and
on the accuracy of the firing.
Engine Operation Proficiency Badge
(Mechanic Handling Superior Badge)
Instituted on September 8, 1911 (Meiji 44)
Notice of name change on February 7, 1922 (Taisho 11)
'
Engine Operation will be changed to High-power Engine Operation'

The test for this badge was for Navy machinists, and it mainly consisted of learning
about coal and coal use on ships.
Gunnery Proficiency Badge (Bombardment Superior Badge)  
艦砲射撃優等章 (
Kanpou Shageki Yuutoushou)
Instituted on September 8, 1911 (Meiji 44)

Awarded to NCO sailors who passed tests in naval artillery. Mostly awarded to gun crew commanders,
firers, ammunition carriers, and heavy artillery aimers (those who aimed the artillery)
Correspondence Proficiency Badge (Correspondence Superior Badge)
通信優等章 (
Tsuushin Yuutoushou)
Instituted on September 8, 1911 (Meiji 44)
(Another source says Meiji 28 [1895])

Awarded to sailors who passed tests in communications, including code, flag and hand signalling, light
[illumination] signalling, and bugling, among others.

Note that if this badge was awarded 3 times to the same sailor, he would get a 1st Class Correspondence
Proficiency Badge
Carpenter Proficiency Badge  (Refit Superior Badge)
工作優等章 (
Kousaku Yuutoushou)
Instituted on April 22, 1930 (Showa 5)

Awarded to Navy pilots (NCOs as well) and airplane mechanics who passed tests in maintaining and repairing equipment during
battle.
Mine Operations Proficiency Badge (Mine Operation Superior Badge)
Instituted on April 14, 1919 (Taisho 8)
Notice of name change on February 23, 1929 (Showa 4)
'
Mine Facilities will be changed to Mine in the title'

Awarded to NCO sailors who passed tests in mines and mine placement. Test subjects included  
schematics of mines, weather, ocean surface, and knowing what parts of the ship are best to damage.
The reverse pin appears to be a replacement.
Some more examples