yokohama mayor and bangkok's executive administrator exchanged memorandums at yokohama city hall. yokohama officials will provide technical assistance for the thai capital's transportation, garbage and sewage systems and will encourage japanese companies to participate. they are also working with a city in the philippines, three companies are preparing to launch ventures to recycle the city's waste. >>> throughout japan deep depopulation is speeding up. 80% of the prefectures are loses residents and experts predict by 2025, major cities will be affected. nhk world has this s >> reporter: in this town children are on the roof chasing. it's a new start of the dating game organized by the local community. they are hoping love will bloom and the couples will stay in the town. the participants get instructions by texts on their mobile phones. one message says -- the girls have to meet up with a man so they won't be caught by -- a great ice breaker. after the game is over everyone reveals who they'd like for their partner. it's lots of fun but also a sea of strategy for town officials a

yokohama firms are already working with sebu city in philippines. three companies are prepares to launch ventures that will recycle the city's waste. >>> elderly people make up a growing portion of the population across east asia. now volunteers in taiwan are helping them get the most out of their retirement years. and for many seniors, the results have been liberating. >> reporter: modeling swimsuits at a beach in taiwan. most mothers are in their 70s. 500 people take part. more than the organizers had hoped for. >> translator: i've never had so much fun. i feel like i'm 50 years younger, like i'm 25. >> reporter: volunteers organized the show. >> translator: if society ages at this pace, we won't be able to take care of all our seniors. we think it's important to help them lead independent lives. >> reporter: the volunteer group has produced a documentary. it follows a group of senior citizens driving their scooters around taiwan. one of the main characters is a widower. >> translator: on a sunny day, the view along the coastal expressway is fanta

yokohama harbor, japan's busiest destination for passenger ships, the harbor has been in operation for more than 150 years.