Landlord-professor Shao Ti Hsu was sentenced last week to spend 30 days in jail and fined $2,500 for assaulting an 11-year-old neighbor who put his family's trash in one of Hsu's garbage cans.

Prince George's County District Court Judge Bess B. Levine sentenced Hus to a six-month jail term suspending all but 30 days. Taken to the Prince George's detention center, Hsu spent one day in jail and then was released on $5,000 bond after he filed an appeal with the county Circuit Court. It marked the second time within three months that the University of Maryland mechanical engineering professor had been incarcerated.

In November, Hsu spent a week in jail when he was found in contempt of court during an unrelated civil suit.

Kevin M. NcNeil, an assistant state's attorney, said Friday that Hsu's most recent legal tangle also may mean that Hsu is in violation of the terms of his probation. Hsu was placed on probation after being found guilty in March of battery and weapons charges in an altercation with a tenant organizer. If Hsu is found to be in violation, he may have to serve his suspended 2 1/2 year jail term, McNeil said.

In the current case, Hsu was convicted of shoving to the ground James S. Wood, who lives across the street from Hsu's Emerson Gardens apartments in Hyattsville. The trial took place Dec. 22.

On Aug. 25, according to court officials and witnesses at the trial, Wood took a plastic trash bag from his parents' house and crossed the street to a garbage dumpster next to the low-rent, three-story apartment building.

Hsu spotted the youth dropping the bag into the garbage bin, called Wood over to his car and told him to either pay for using the trash receptacle or retrieve the garbage. Wood refused.

Then Hsu, a 64-year-old millionaire, reached into the trash bin, picked up several garbage bags and emptied their contents onto the Wood family's lawn at 4911 43rd Ave. Hsu testified he "placed" the bags on Wood's property and then left.

But Wood testified that he approached Hsu as he was getting into his blue Cadillac and asked the landlord to pick up the trash. The professor shoved him against the outer side-view mirror, Wood testified, and then flung open the car door, knocking Wood onto the street.

The boy's mother, Helen P. Wood, called Hyattsville police that night and filed charges against Hsu on behalf of her son.

Hsu brought four witnesses to contest the boy's statements, but Judge Levine found Hsu guilty, and said she was choosing "quality, not quantity of the testimony."

Hsu, in an interview, called the judge's ruling "stupid" and Wood's testimony "a complete lie."

After the verdict, Hsu, acting as his own attorney, asked for a retrial, saying that if he had had an attorney, he "would have been able to point out to the court that both (Helen Wood) and her son are liars." Levine denied Hsu's request.

Robert L. Gluckstern, chancellor of the College Park campus, said University of Maryland officials will not consider any action against Hsu, who holds a tenured faculty position, until all appeals of his criminal convictions have been exhausted.

In October, a Prince George's County District Court judge moved two of Hsu's appeals to Calvert County for trail after the landlord claimed excessive local media coverage had ruined his chances of finding an impartial jury locally.

In one of those cases, Hsu is seeking to overturn a March 28 conviction for using a steel pole and chemical stray in an assault on a tenant organizer who had been visiting Hsu's Hyattsville apartments.

In the other case, Hsu is appealing a judge's ruling last April that found that county inspectors had condemned as "unfit for human habitation" to two families.

In the aftermath of a squabble last year between two county housing agencies, a Circuit Court judge restored Hsu's rental license, despite a contention that the professor had not remedied housing code violations such as holes in walls, missing ceilings, broken plumbing and animal feces.