Problem: Background: Weather Report was an American jazz fusion band of the 1970s and early 1980s. The band was initially co-led by the Austrian-born keyboard player Joe Zawinul, the American saxophonist Wayne Shorter and Czech bassist Miroslav Vitous. Due to creative and financial disagreements, Vitous left the band after a few years. Zawinul took increasing control and steered the band towards a more funk, R&B oriented sound.
Context: 1976's Black Market album was perhaps the most rock-oriented work which the group had produced to date. Weather Report's music had evolved further from open-ended funk jams into more melody-oriented, concise forms, which also offered a greater mass-market appeal. Zawinul further consolidated his use of keyboard synthesizers, while Shorter experimented with an early form of wind synthesizer, the Lyricon.  However, the album was recorded during yet another period of change for the group, with multiple personnel shuffles. Although Alyrio Lima played percussion on one track, he was replaced during the sessions by Don Alias (his first appearance with the group since the debut album debacle) and by Alex Acuna (a Peruvian drummer and conga player based in Las Vegas, who had played with Elvis Presley and Ike Turner, among others). Alphonso Johnson was also worn out from the strain put on the rhythm by the band's frequent changes of drummer. During a break in activity halfway through the recording of Black Market, Johnson opted to leave Weather Report to play with the Billy Cobham/George Duke Band (which featured a young John Scofield on guitar).  Prior to his departure, Johnson played on all but two of the new album's tracks. His replacement was Jaco Pastorius, a virtuoso fretless bass guitarist from Florida, who had been in touch with Zawinul for several years, and who came in to play on "Cannon Ball" and his own composition "Barbary Coast". Zawinul and Shorter had assumed that Chester Thompson would be departing alongside his friend Johnson, and for the second set of sessions they replaced him (on Jaco Pastorius' recommendation) with the former Mahavishnu Orchestra drummer Narada Michael Walden. Although Walden played on several album tracks, he ultimately proved unsuitable. Thompson returned for the final Black Market sessions, but left again after failing to gel as a rhythm section with Pastorius (whose style was much busier than that of Johnson). Thompson subsequently joined Genesis as their touring drummer.  Black Market continued Weather Report's ongoing run of success, selling well and being the fourth of the band's albums to win the album of the year award from Down Beat magazine. For the subsequent tour, Alex Acuna moved from percussion to the drum kit, and Don Alias was replaced by the young Puerto Rican percussionist Manolo Badrena, who had previously played with various Latin rock bands and with Art Blakey. The band made a very well-received appearance at the Montreux Jazz Festival, which was filmed for future release.
Question: Who moved
Answer: Alyrio Lima played percussion on one track, he was replaced during the sessions by Don Alias

Background: AKB48 (pronounced A.K.B. Forty-eight) are a Japanese idol girl group named after the Akihabara (Akiba for short) area in Tokyo, where the group's theater is located. The group has expanded since then to include over 130 members as of December 2015, aged from their early teens to their mid-20s. AKB48's producer, Yasushi Akimoto, wanted to form a girl group with its own theater (unlike pop groups performing occasional concerts and seen on television) and performing daily so fans could always see them live. This "idols you can meet" concept includes teams which can rotate performances and perform simultaneously at several events and "handshake" events, where fans can meet group members.
Context: AKB48 was founded as "idols you can meet". The group's chief producer, Yasushi Akimoto, said that his goal was to create a unique idol group which, unlike other idol groups which perform occasional concerts and appear primarily on television, would perform regularly in its own theater. The AKB48 Theater is in the Don Quijote store in Akihabara, Tokyo.  The group is split into several teams, reducing its members' workload (since the theater's near-daily performance is by only one team) and enabling AKB48 to perform simultaneously in several places. According to former member Misaki Iwasa, each team has its own theme. Team A represents freedom; Team B is idol-like, with cute costumes, and Team K has a strong, powerful image. According to an early press release the group was intended to have 16 members on each of three teams, for a total membership of 48; but its membership has varied over time, and has exceeded 120 people. New members are called trainees (Yan Jiu Sheng , kenkyusei) who are understudies for the group, performing occasionally in the theater as a team. In addition to their performances with the group, members are promoted by the Japanese mass media. AKB48 regularly hosts events, where fans can interact with the members, such as taking pictures or shaking hands with the members.  The group members' ages range from their early teens to over 20, and they are selected from regular auditions. Members are not allowed to date, and must be well-behaved; any violation of these restrictions is to be punished, possibly by expulsion from the group. AKB48 has a system that allows members to "graduate" from the group when they are older and are replaced by trainees who are promoted. Monica Hesse of The Washington Post described the AKB48 audition process as "rolling American Idol-esque".
Question: What was concept?
Answer:
to create a unique idol group