• 정보처리학회논문지D
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• 제16D권6호
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• pp.835-844
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• 2009

일반적으로 데이터베이스 시스템에서의 질의 수행은 대부분의 경우 빠른 응답시간과 더 적은 메모리 사용량을 장점으로 가지는 파이프라이닝 기법으로 이루어진다. 이 때, 질의 수행 계획(QEP)의 각각의 연산 노드들은 Open(), Next(), Close() 함수들을 지원하는 iterator의 인터페이스를 가진다. 그런데, 플래시 메모리 기반의 휴대용 기기들을 위한 임베디드 데이터베이스 시스템에서는 iterator의 Next() 함수뿐만 아니라, 현재 레코드의 이전 레코드를 리턴해주는 Previous()와 같은 함수를 필요로 하는 경우가 많다. 이는 임베디드 환경의 경우 각각의 프로그램이 사용할 수 있는 메모리의 양이 제한적이므로, 사용자가 이전 레코드를 요청하는 경우, 결과 레코드 커서가 현재 레코드를 기준으로 이전 레코드를 다시 가져와야 하기 때문이다. 본 논문에서는 이러한 임베디드 데이터베이스 시스템의 질의 수행 시 각각의 연산 노드들이 Next() 함수뿐만 아니라 Previous() 함수를 블록 단위로 지원할 수 있도록 새롭게 설계 구현하는 과정에서 발생하는 방향 전환 문제를 소개하고 이를 해결하기 위한 블록 단위 스키핑 기법을 제안한다.

• 한국항해항만학회지
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• 제45권3호
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• pp.138-147
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• 2021

한진해운 파산 및 해운동맹의 재정립 등으로 부산항 컨테이너터미널의 운영 효율성 및 생산성 분석의 필요성이 증가하고 있다. 본 논문은 항만공사 공시자료 및 수집된 터미널 내부자료를 바탕으로 DEA 분석 및 Malmquist 생산성 지수 모형을 활용하여 부산신항 컨테이너 터미널 5개사의 효율성 및 생산성을 분석하였다. 분석결과 컨테이너터미널 5개사의 평균 효율성은 2018년 증가하였으나 2019년 소폭 하락한 것으로 나타났으며, Malmquist 지수를 통해 종합적인 생산성 변화를 살펴보면 A사를 제외한 모든 터미널이 생산성이 진보한 것으로 나타났다. 또한 설비 생산성의 경우 부산신항 남컨테이너터미널보다 북컨테이너터미널에 위치한 운영사들이 높은 것으로 나타났고, 자본 생산성의 경우 국적 선사인 HMM이 기항하는 D사가 가장 높은 것으로 나타났다. 노동 생산성의 경우 C사가 가장 높은 생산성을 보였으며, 선박작업 생산성의 경우 A사가 가장 높은 생산성을 보였다.

• Archives of Plastic Surgery
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• 제38권2호
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• pp.161-165
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• 2011

Purpose: Zygomaticomaxillary complex (ZMC) fracture is one of the most common facial injuries after facial trauma. As ZMC composes major facial buttress, it is a key element of the facial contour. So, when we treat these fractures, the operator should have a concern with the symmetry to restore normal appearance and function. But sometimes, unfavorable results may occur. The aim of this study is to analyze the unsatisfied midfacial contour after ZMC fractures reduction retrospectively and to point out the notandum. Methods: 369 patients, treated for fractures of the ZMC were included in the study. After the operation, such as open reduction and internal fixation (ORIF with titanium or absorbable materials), open reduction, and closed reduction, midfacial contour was evaluated with plain films and 3-dimensional computed tomography. And unfavorable asymmetric midfacial contours were correcterd by secondary correction and re-evaluated. Gross photographs were obtained at outpatient clinic. Results: Total of 38 patients had got a facial asymmetry and among of them 24 patients were treated secondary revisional ORIF operations for correction of unfavorable result of after primary reduction. Two of them had received tertiary operations, three patients had got osteotomy more than after one year and six patients had got minor procedures. The etiology of asymmetry were lateral displaced simple fracture of arch (n=2), lateral displaced comminuted fracture of arch (n=6), comminuted arch fracture combined posterior root fracture (n=9), and communited arch and body fracture (n=12), severely contused soft tissue (n=9). After the manipulations outcomes were acceptable. Conclusion: To prevent the asymmetry in ZMC fracture reduction, complete analysis of fracture, choice of appropriate operation technique, consider soft tissue, and secure of zygoma position are important. Especially, we should be more careful about communited fracture of zygomatic body and lateral displacement, root fracture of zygomatic arch. Because they are commom causes that make facial asymmetry. To get optimal result, ensure the definite bony reduction.

• Asian-Australasian Journal of Animal Sciences
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• 제13권11호
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• pp.1619-1637
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• 2000

A review was undertaken to obtain information on the range of beak-trimming methods available or under development. Beak-trimming of commercial layer replacement pullets is a common yet critical management tool that can affect the performance for the life of the flock. The most obvious advantage of beak-trimming is a reduction in cannibalism although the extent of the reduction in cannibalism depends on the strain, season, and type of housing, flock health and other factors. Beak-trimming also improves feed conversion by reducing food wastage. A further advantage of beak-trimming is a reduction in the chronic stress associated with dominance interactions in the flock. Beak-trimming of birds at 7-10 days is favoured by Industry but research over last 10 years has shown that beak-trimming at day-old causes the least stress on birds and efforts are needed to encourage Industry to adopt the practice of beak-trimming birds at day-old. Proper beak-trimming can result in greatly improved layer performance but improper beak-trimming can ruin an other wise good flock of hens. Re-trimming is practiced in most flocks, although there are some flocks that only need one trimming. Given the continuing welfare scrutiny of using a hot blade to cut the beak, attempts have been made to develop more welfare friendly methods of beak-trimming. Despite the developments in design of hot blade beak-trimmers the process has remained largely unchanged. That is, a red-hot blade cuts and cauterises the beak. The variables in the process are blade temperature, cauterisation time, operator ability, severity of trimming, age of trimming, strain of bird and beak length. This method of beak-trimming is still overwhelmingly favoured in Industry and there appears to be no other alternative procedures that are more effective. Sharp secateurs have been used trim the upper beak of both layers and turkeys. Bleeding from the upper mandible ceases shortly after the operation, and despite the regrowth of the beak a reduction of cannibalism has been reported. Very few differences have been noted between behaviour and production of the hot blade and cold blade cut chickens. This method has not been used on a large scale in Industry. There are anecdotal reports of cannibalism outbreaks in birds with regrown beaks. A robotic beak-trimming machine was developed in France, which permitted simultaneous, automated beak-trimming and vaccination of day-old chicks of up to 4,500 chickens per hour. Use of the machine was not successful because if the chicks were not loaded correctly they could drop off the line, receive excessive beak-trimming or very light trimming. Robotic beak-trimming was not effective if there was a variation in the weight or size of chickens. Capsaicin can cause degeneration of sensory nerves in mammals and decreases the rate of beak regrowth by its action on the sensory nerves. Capsaicin is a cheap, non-toxic substance that can be readily applied at the time of less severe beak-trimming. It suffers the disadvantage of causing an extreme burning sensation in operators who come in contact with the substance during its application to the bird. Methods of applying the substance to minimise the risk to operators of coming in contact with capsaicin need to be explored. A method was reported which cuts the beaks with a laser beam in day-old chickens. No details were provided on the type of laser used, or the severity of beak-trimming, but by 16 weeks the beaks of laser trimmed birds resembled the untrimmed beaks, but without the bill tip. Feather pecking and cannibalism during the laying period were highest among the laser trimmed hens. Currently laser machines are available that are transportable and research to investigate the effectiveness of beak-trimming using ablasive and coagulative lasers used in human medicine should be explored. Liquid nitrogen was used to declaw emu toes but was not effective. There was regrowth of the claws and the time and cost involved in the procedure limit the potential of using this process to beak-trim birds.