• Industrial Engineering and Management Systems
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• 제15권1호
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• pp.32-40
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• 2016

This paper considers a special case of a three machine flow shop scheduling problem in which operation processing time of each job is ordered such that machine 1 has the longest processing time, whereas machine 3, the shortest processing time. The objective of the problem is the minimization of the total completion time. Although the problem is simple, its complexity is yet to be established to our best knowledge. This paper first introduces the problem and presents some optimal properties of the problem. Then, it establishes several special cases in which a polynomial-time optimal solution procedure can be found. In addition, the paper proves that the recognition version of the problem is at least binary NP-complete. The complexity of the problem has been open despite its simple structure and this paper finally establishes its complexity. Finally, a simple and intuitive heuristic is developed and the tight worst case bound on relative error of 6/5 is established.

• 대한수학회논문집
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• 제31권4호
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• pp.827-844
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• 2016

Here, in this paper, we aim at establishing some new unified integral and differential formulas associated with the $\bar{H}$-function. Each of these formula involves a product of the $\bar{H}$-function and Srivastava polynomials with essentially arbitrary coefficients and the results are obtained in terms of two variables $\bar{H}$-function. By assigning suitably special values to these coefficients, the main results can be reduced to the corresponding integral formulas involving the classical orthogonal polynomials including, for example, Hermite, Jacobi, Legendre and Laguerre polynomials. Furthermore, the $\bar{H}$-function occurring in each of main results can be reduced, under various special cases.

• 호남수학학술지
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• 제46권3호
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• pp.407-427
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• 2024

The purpose of this article is to bring together the Horadam numbers and 3-parameter generalized quaternions, which are a general form of the quaternion algebra according to 3-parameters. With this purpose, we introduce and examine a new type of quite big special numbers system, which is called Horadam 3-parameter generalized quaternions (shortly, Horadam 3PGQs), and special cases of them. Besides, we compute both some new equations and classical well-known equations such as; Binet formulas, generating function, exponential generating function, Poisson generating function, sum formulas, Cassini identity, polar representation, and matrix equation. Furthermore, this article concludes by presenting the determinant, characteristic polynomial, characteristic equation, eigenvalues, and eigenvectors in relation to the matrix representation of Horadam 3PGQ.

• 화약ㆍ발파
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• 제33권1호
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• pp.21-26
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• 2015

진동속도를 진동레벨로 환산하는 몇 가지 식을 검토하고 환경분쟁 사례에 적용하여 그 타당성을 검토하였다. 또 구조물에 대한 진동피해가 인정되었지만 정신적 피해가 인정되지 않은 사례에 대해 검토하고 그 원인을 고찰하여 그 원인이 잘못된 환산식을 적용하였거나, 침하 등 건설상의 피해를 진동피해로 잘못 인정된 경우임을 보였다.

• Journal of Chest Surgery
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• 제7권1호
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• pp.61-66
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• 1974

Primary tumors of the chest wall are rare than those of other portions of the body. Soft tissue tumors of the chest wall, though these are benign or malignant, should not be paid special attentions about their management than other soft tissue tumors of the body. Thoracic skeletal tumors, however, have some problems in the treatment because of defect in chest wall leading to herniation of lung and paradoxical movement of thoracic cage. The authors experienced 10 case of primary chest wall tumors at the department of thoracic and cardiovascular surgery, the national medical center, during last 15 years. Five of 10 cases were soft tissue tumors, and they were 2 case of lipoma and each one case of myxosarcoma and leiomyosarcoma. Among 5 bone tumors there no cases of sternal tumor, and their histopathological diagnosis were each one of fibrous dysplasia, giant cell tumor, osteochondroma, Ewing`s sarcoma and osteogenic sarcoma. Wide excision, though it was palliative one in certain case, was performed in 9 cases and only diagnostic incisional biopsy in one case, There were no postoperative deaths during admission to the hospital and all cases were missed during short term follow up after discharge from the hospital.

• Journal of Chest Surgery
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• 제28권12호
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• pp.1144-1149
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• 1995

Adenocarcinoma involving esophago-gastric junction[EGJ is usually originated from the gastric cardia and it presents unique clinical manifestations, requires special surgical care, and bears a much poor prognosis. We analyse the clinical data of 109 adenocarcinoma involving EGJ operated between August, 1987 and March, 1994. Curative resection of primary tumor including esophagus and lymph node dissection was possible on 102 cases[93.5% . Among these cases, 89 cases were advanced state over the stage III. The operative mortality was 1.8% and postoperative morbidity was 16.5%. The overall 3 year and 5 year survival rate was 48.5%, 34.1% each, and median survival was 27.5 month in the curative resected cases. The treatment failure was mainly distant metastsis including lymph node, except one local recurrence.Among many factors influencing long term results of resected adenocarcinoma involving EGJ, the only effort a surgeon can make is to attain completeness of tumor removal by dissecting all involved lymph node and ensuring adequate tumor free margins of both esophageal and cardiac side.

• The Korean Journal of Pain
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• 제22권2호
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• pp.176-180
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• 2009

Cases of pyogenic spondylodiscitis are relatively rare diseases that concern 2-7% of total cases of osteomyelitis. Owing to the low frequency and initial nonspecific nature of signs and symptoms, diagnosis is often delayed up to 2-6 months. If the proper treatment is not established due to a diagnostic delay, there is a possibility of a serious neurologic deficit and spinal instability. We report two cases of infectious spondylodiscitis which were misdiagnosed as compression fracture and spinal stenosis respectively. They could be correctly diagnosed after MRI and laboratory test and under the recovery state after an antifungal and antibiotic medication. Special careful attention during the diagnostic procedure is a really important step considering the diagnostic delay and its resultant unsatisfactory outcome.

• ETRI Journal
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• 제19권4호
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• pp.363-388
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• 1997

This paper describes a research result on automatic generation of abstract test cases from formal specifications by applying many related algorithms and techniques such as the testing framework, rural Chinese postman tour and unique input output sequence concepts. In addition, an efficient algorithm for verifying the strong connectivity of the reference finite state machine and the concept of unique event sequence are explained. We made use of several techniques to from an integrated framework for abstract test case generation from LOTOS and SDL specifications. A prototype of the proposed framework has been built with special attention to real protocol in order to generate the executable test cases in an automatic way. The abstract test cases in tree and tabular combined notation (TTCN) language will be applied to the TTCN compiler in order to obtain the executable test cases which re relevant to the industrial application.

• Wind and Structures
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• 제32권5호
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• pp.501-508
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• 2021

The turbine industry demands a reliable design with affordable cost. As technological advances begin to support turbines of huge sizes, and the increasing importance of wind turbines from day to day make design safety conditions more important. Wind turbines are exposed to environmental conditions that can affect their installation, durability, and operation. International Electrotechnical Commission (IEC) 61400-1 design load cases consist of analyses involving wind turbine operating conditions. This design load cases (DLC) is important for determining fatigue loads (i.e., forces and moments) that occur as a result of expected conditions throughout the life of the machine. With the help of FAST (Fatigue, Aerodynamics, Structures, and Turbulence), an open source software, the NREL 5MW land base wind turbine model was used. IEC 61400-1 wind turbine design standard procedures assessed turbine behavior and fatigue damage to the tower base of dynamic loads in different design conditions. Real characteristic wind speed distribution and multi-directional effect specific to the site were taken into consideration. The effect of these conditions on the economic service life of the turbine has been studied.

• 한국지능시스템학회논문지
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• 제20권4호
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• pp.455-462
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• 2010

단순하고 스테이블한 머징알고리즘의 비교횟수와 관련된 worst case 복잡도를 분석한다. 복잡도 분석을 통해 소개되는 알고리즘이 m 과 n, $m{\leq}n$ 사이즈의 두 수열에 대해 O(mlog(n/m))의 비교횟수를 요구하는 사실을 증명한다. 그래서 병합에 있어서의 하계가 $\Omega$(mlog(n/m))이라는 사실로부터 우리의 알고리즘이 비교횟수와 관련해 점근적 최적 알고리즘에 해당함 을 추론가능하다. worst case 복잡도 증명을 위해 모든 입력수열로 구성된 정의구역을 두개의 서로소인 집합으로 나눈다. 그런 후 서로소인 각각의 집합으로 부터 특수한 subcase를 구별한 후 이들 subcase 각각에 대해 점근적 최적성을 증명한다. 이 증명을 바탕으로 나머지 모든 경우에 대한 최적성 또한 추론 또는 증명 가능함을 소개한다. 이로써 우리는 복잡도 분석이 까다로운 알고리즘에 대해 투명한 하나의 해를 제시한다.