• Journal of Animal Science and Technology
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• 제45권4호
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• pp.641-648
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• 2003

본 연구에서는 돈사 폐수내의 인과 질소를 함께 결정화하여 회수하고 그 상등액을 전기분해 시키는 회분식 돈사 폐수공정에서의 오염물질 부하량과 수처리시간 변화에 따른 처리효율의 변화 및 각 오염물질 제거특성을 파악하였다. Struvite 형성을 위한 Mg원으로는 $MgCl_2$를 사용하였고 주입량은 폐수내 인 기준 1.3 Mole이었다. 총 4개의 운전(Run I, II, III, IV)에서 얻어진 평균 제거효율과 그 제거특성을 분석한 결과 인의 경우 부하량 변화에 따른 처리효율의 변화는 관찰되지 않았으며 제거의 주요 역할을 하는 반응조는 Struvite 반응조로서 적정 Mg원만 제공된다면 pH 조절제 첨가 없이 폭기만으로도 부하량에 관계없이 88% 이상의 제거가 MAP 형성을 통해 얻어지는 것으로 나타났다. 높은 암모니아성 질소 제거효율을 유지하기 위한 적정 부하량은 약 100g/$m^3$.d로서 동 부하량 이하에서는 부하량이 증가함에 따라 제거량도 증가하면서 90% 이상의 높은 효율과 일정한 제거특성을 보인 반면 그 이상에서는 불안정한 제거특성을 나타내면서 제거효율이 감소하였다. TOCs의 경우에는 부하량 변화에 따른 처리효율 변화는 관찰되지 않았으며, 그 제거효율은 수처리 시간에 의존적인 것으로 나타났다 ($r^2$ = 0.97). 색도 제거 효율은 전기분해조 용적기준 수처리시간 2일 이상에서 94%의 매우 높고 일정한 효율을 얻을 수 있었다.

• 대한수학교육학회지:학교수학
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• 제15권4호
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• pp.833-846
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• 2013

본 논문에서는 우리나라 초등학교 1~2학년 수학 교과서/익힘책 <수와 연산> 영역에서 '곱', '자릿값', '구구', '숫자'라는 용어를 잘못 사용하거나 또는 비일관적으로 사용하고 있는 실태를 분석하고 있다. 이러한 분석을 바탕으로 다음 네 가지를 결론으로 제시한다. 첫째, ${\ll}$수학 3${\gg}$ 교과서에서 '곱'을 정의해야 한다. ${\ll}$수학 3${\gg}$ 교과서/익힘책에서 곱셈을 도입하지만, 그 계산 결과를 '곱'이라 하고 있지는 않다. 둘째, 초등학교 2학년 수학에서 '자릿값'이라는 용어의 사용을 재고할 필요가 있다. ${\ll}$수학 3${\gg}$과 ${\ll}$수학 4${\gg}$ 교과서/익힘책에서 사용하는 '자릿값'이라는 용어의 의미는 명료하지 않다. 셋째, ${\ll}$수학 2${\gg}$와 ${\ll}$수학 4${\gg}$ 교과서에서 '덧셈구구표'와 '뺄셈구구표'라는 표현을 사용하지 말아야한다. 넷째, 초등학교 1, 2학년 수학에서 '숫자'의 사용을 최소화하고, 가급적 '수'로 통일해서 사용하는 것을 고려할 필요가 있다.

• 해양환경안전학회지
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• 제26권6호
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• pp.644-655
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• 2020

본 연구는 항해사가 근접상황에서 심리적 충돌의 두려움으로 당황하여 규정된 충돌 회피조치를 수행하지 못하는 인적오류 상황을 연구하였다. 연구 목적은 선박 간 근접상황에서 항해사의 인적특성 요인인 승선경력, 면허등급, 연령요인이 충돌위험도에 미치는 영향을 규명하는 것이다. 본선과 상대선박 간 네 가지 대표적인 근접상황의 충돌침로에서 항해사가 지각한 충돌위험도 값을 측정, 정량화된 데이터를 얻기 위하여 시뮬레이터를 이용하여 충돌위험도 측정실험을 설계하고 두 척의 선박이 거리 2.5해리에서 충돌상황까지 상호 10노트의 속도로 접근할 때 본선의 30명의 항해사의 심장박동변이를 측정하여 항해사가 지각한 충돌위험도 측정데이터를 확보하였다. 측정값에 대한 다중회귀분석 결과 항해사의 승선경력과 면허등급 요인은 충돌위험도에 부(-)의 영향을 미쳤고, 연령은 영향을 미치지 않았다. t-검정 결과 승선경력≤4년인 항해사는 승선경력≥5년인 항해사 보다 충돌위험도 값이 유의미하게 높았고 면허등급 요인은 4 ~ 6급 그룹이 2 ~ 3급 그룹보다 충돌위험도 값이 유의미하게 높게 나타났다. 본 연구결과는 충돌위험경보시스템 개발에 적용될 수 있을 것이다.

• Journal of Nutrition and Health
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• 제43권6호
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• pp.653-660
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• 2010

Along with the steady growth of health functional food (HFF) markets, research evaluating the human effects of HFF has been expanding. In this study, we investigated the regulatory and management system of human study on HFF in the USA, Japan and UK, and the Korean domestic regulations on HHF, medicines, medical devices, cosmetics and biotechnology in order to improve the domestic management system. In these four countries, institutional review board (IRB) or research ethics committee (REC) approvals are required for on human study of HHF, but regulatory and management systems differ from country to country. In the USA, human studies on HFF for structure/function claims do not require the FDA's prior approval but clinical trials of the disease treatment effects of HHF require prior approval from the FDA. In the USA, IRBs are managed by the Department of Health and Human Services (DHHS) rather than the FDA, and IRBs in those institutions which would execute the clinical trials requiring prior approval from the FDA or human studies funded by the USA federal government are required to be registered on the DHHS. In the UK, although the government does not require prior approval of human study, authorized RECs managed by the National Research Ethics Service (NRES) and other independent RECs review the human study. In Japan, human study for HFF must conform with "Ethical guidelines for epidemiological research" and IRB registration has not been required. In Korean domestic regulations, the responsibilities, compositions, functions and operations of IRBs on medicines, medical devices and biotechnology are legally specified, but not those of IRB on HHF. These foreign statuses for the management of human study on HFF and comparisons with Korean regulations are expected to be used as basic data to improve the domestic legal system.

• 유통과학연구
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• 제13권11호
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• pp.123-130
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• 2015

Purpose - Due to highly elevated levels of competition, many companies today have to face the problem of decreasing profits even when their actual sales volume is increasing. This is a common phenomenon that is seen occurring among companies that focus heavily on quantitative growth rather than qualitative growth. These two aspects of growth should be well balanced for a company to create a sustainable business model. For supply chain management (SCM) planners, the optimized, quantified flow of resources used to be of major interest for decades. However, this trend is rapidly changing so that managers can put the appropriate balance between sales volume and sales quality, which can be evaluated from the profit margin. Profit optimization is a methodology for companies to use to achieve solutions focused more on profitability than sales volume. In this study, we attempt to provide executional insight for companies considering implementation of the profit optimization system to enhance their business profitability. Research design, data, and methodology - In this study, we present a comprehensive explanation of the subject of profit optimization, including the fundamental concepts, the most common profit optimization logic algorithm -linear programming -the business functional scope of the profit optimization system, major key success factors for implementing the profit optimization system at a business organization, and weekly level detailed business processes to actively manage effective system performance in achieving the goals of the system. Additionally, for the purpose of providing more realistic and practical information, we carefully investigate a profit optimization system implementation case study project fulfilled for company S. The project duration was about eight months, with four full-time system development consultants deployed for the period. To guarantee the project's success, the organization adopted a proven system implementation methodology, supply chain management (SCM) six-sigma. SCM six-sigma was originally developed by a group of talented consultants within Samsung SDS through focused efforts and investment in synthesizing SCM and six-sigma to improve and innovate their SCM operations across the entire Samsung Organization. Results - Profit optimization can enable a company to create sales and production plans focused on more profitable products and customers, resulting in sustainable growth. In this study, we explain the concept of profit optimization and prerequisites for successful implementation of the system. Furthermore, the efficient way of system security administration, one of the hottest topics today, is also addressed. Conclusion - This case study can benefit numerous companies that are eagerly searching for ways to break-through current profitability levels. We cannot guarantee that the decision to deploy the profit optimization system will bring success, but we can guarantee that with the help of our study, companies trying to implement profit optimization systems can minimize various possible risks across various system implementation phases. The actual system implementation case of the profit optimization project at company S introduced here can provide valuable lessons for both business organizations and research communities.

• Journal of Korean Neurosurgical Society
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• 제30권12호
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• pp.1361-1368
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• 2001

Objective : "Paraclinoid" aneurysms include those aneurysms arising from the internal carotid artery between the site of emergence of the carotid artery from the roof of the cavernous sinus and the origin of the posterior communicating artery. The authors reviewed and analysed the results of surgical approaches to paraclinoid aneurysms treated with transcranial surgery and endovascular surgery. Methods : Between January 1998 and May 1999, 14 patients were treated surgically through ipsilateral and contralateral pterional approaches, and anterior interhemispheric approach, and endovascular surgery for paraclinoid aneurysms. All transcranial approaches were performed by same surgeon. The medical records, neuroimaging studies and videotapes which had been recorded operations were reviewed retrospectively. Results : Twelve patients presented with subarachnoid hemorrhage and ICH. Nine of fourteen patients had multiple aneurysms. Thirteen cases were small and one was a large aneurysm. Six patients were treated through ipsilateral approaches, six contralateral pterional approaches, one anterior interhemispheric approach and one primarily by GDC embolization. All aneurysms treated through contralateral approaches were multiple aneurysms. Neck clipping was performed in 9(69.2%) of the thirteen aneurysms, wrapping in four cases, among them three cases were followed by GDC embolization. The surgical outcomes were : Glasgow Outcome Scale(GOS) I 71.4%, GOS II 21.4% and GOS V 7.1%. Conclusion : The surgical approaches to paraclinoid aneurysms should be chosen after careful anatomical evaluation of aneurysm and its neighboring structures. 3D-CT angiography and/or the raw data of MR angiography were useful. This study supports the usefulness of the contralateral approach to paraclinoid aneurysm associated with multiple aneurysms, unruptured and small aneurysms whose dome projecting medially, superiorly and dorsally. The determination of contralateral approach to small and medially projecting paraclinoid aneurysm may be stressful to operator, thus we believe anterior interhemispheric approach is better alternated. Also we recommend the endovascular surgery after reinforcement of aneurym neck and dome in the case with difficulty in clipping.

• 대한교통학회지
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• 제26권5호
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• pp.163-174
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• 2008

기존의 4단계 교통수요추정 모형은 거시적인 장래 교통수요 예측을 위해 사용되어 왔으나 정확성에 대한 문제가 지속적으로 제기되어 왔다. 장래 수요추정의 정확성을 높이기 위해서는 신뢰성 있는 자료의 확보, 장래 사회 경제 지표의 예측의 합리성 등 근본적 해결방법이 있으며 모형의 추정방법을 달리하는 것도 상당히 중요한 해결방법이라 하겠다. 과거와 달리 교통수요추정 모형은 단순히 교통인프라 구축에 따른 교통수요추정과 같은 거시적인 분석뿐만 아니라 교통수요관리정책의 효과분석, 교통운영분석의 적용 등 미시적인 분석에 대한 요구가 증대되고 있다. 본 연구에서는 인간의 활동에 기반을 둔 활동기반 교통수요추정에 대하여 소개하며 통행자의 일일 활동에 대한 조사를 기반으로 한 시 공간 활동인구 추정을 통한 통행수요를 예측하였다. 연구결과 개별 건물단위의 시간대별 활동인구의 추정은 비교적 정확한 것으로 분석되었으며 예측된 통행수요 또한 정확성이 높은 것으로 나타났다. 본 연구의 결과는 인간의 활동에 기반을 둔 시 공간 활동기반모형은 거시적인 교통수요추정뿐만 아니라 미시적 추정이 가능하므로 다양한 미시적 교통체계분석에 활용될 수 있을 것으로 기대되며 이를 위해 활동기반 자료와 토지이용에 대한 공간자료(GIS)의 확보가 필수적이라 하겠다.

• 대한관절경학회지
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• 제4권1호
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• pp.49-53
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• 2000

목적 :. 만성 견관절 충돌증후군에 대한 수술적 치료로서 사용한 관절경적 전방 견봉 성형술의 치료 결과를 분석하고 임상적 효용성을 평가하고자 하였다. 대상 및 방법 : 1995년 7월부터 1997년 12월까지 만성 견관절 충돌증후군 환자 중 6개월 이상 보존적 치료에도 불구하고 증상이 호전되지 않아 관절경을 이용하여 전방 견봉 성형술을 시행한 26명의 환자, 27례의 견관절들을 대상으로 하였다. 심한 퇴행성 관절염 회전근 개 전층 파열 및 견관절 비출구 충돌증후군 (nonoutlet impingement) 등은 모두 연구 대상에서 제외하였다. 평균 추시 기간은 2년 3개월(범위, 1년 7개월-3년 11개월)이었다. 임상적인 결과 판정은 UCLA 견관절 평가지수를 이용하였다. 결과 : 27례 중 23례$(85.2\%)$에서 매우 우수 또는 우수한 결과를 보였으며, 4례$(14.8\%)$에서 양호의 결과를 나타내었다. 환자의 만족도는 27례 중 26례$(96.3\%)$에서 주관적인 만족을 나타내었고, 1례 $(3.7\%)$에서 불만족을 나타내었으며 이 경우 Parkinson 증후군과 경추 후종인대 골화증 및 제 5-6번 경추의 척추 협착증이 동반된 환자였다. 결론 : 관절경적 전방 견봉 성형술은 특히 술전 동통의 정도가 술후 현저히 개선되는 등 증상 완화에 우수한 결과를 예상할 수 있는 만성 견관절 충돌증후군의 효율적 치료법이지만, 견관절 및 그 주위의 병변이나 전신 질환 등이 동반될 경우 치료 결과에 영향을 미칠 수 있다.

• 한국병원경영학회지
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• 제25권2호
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• pp.45-56
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• 2020

Purpose: The purpose of this study is to investigate medical care behaviors influencing accuracy of the payment based New diagnosis-related groups (DRG) compared to fee for service (FFS) in hospitalized patients with medical illness. Methodology: In order to estimate the difference in medical costs between New DRG and FFS depending on medical care behaviors, medical records and hospital claims data (n=4,232) were utilized, which were collected from a single public hospital during the first-half of 2018. Data were analyzed by descriptive statistics, t-test, chi-square test, and multivariate binary logistic regression. Findings: The average difference in medical costs between New DRG and FFS were KRW 506,711±13,945 with incentives and KRW -51,506±12,979 without incentives, respectively. Forty-four point two percent (44.2%, n=1,872) of total subjects were shown to have negative compensation in overall medical costs with New DRG compared to the costs with FFS. Medical care behaviors that affected on the negative compensation were the presence of severe bed sores on admission, medical consultations, death, operations, medications and laboratory or imaging tests with unit price over KRW 100,000, hospital-acquired complications or underlying comorbidities, elderly patients (≧65 years), and hospitalized for more than average inpatient days defined by New DRG (p<0.001). The difference in average medical cost between New DRG and FFS for a group with mild illness was KRW -11,900±10,544, whereas it was KRW -196,800±46,364 for a group with severe illness (p<0.0001). Practical Implications: These findings suggest that New DRG payment model without incentives may incompletely cover the variation of medical costs in real clinical practice. Therefore, policy makers need to consider that the current New DRG reimbursement should be focused and refined to improve accuracy of payment on medical care resources utilized in severe and complex medical conditions.

• Journal of Gastric Cancer
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• 제4권3호
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• pp.196-203
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• 2004

The Information Committee of the Korean Gastric Cancer Association sent questionnaires to 31 laparoscopic gastric surgeons about their personal experiences with laparoscopic gastric surgery from 2001 to 2003. Twenty-four surgeons responded to the questionnaires (response rate: $77.4\%$).The number of laparoscopic gastric surgeries from 2001 to 2003 was 1,130 and increased from 209 in 2001 to 593 in 2003. The number of operations for a gastric adenocarcinoma also increased from 87 cases in 2001 to 403 cases in 2003. Laparoscopic radical procedures, such as a laparoscopyassisted distal gastrectomy or total gastrectomy (LADG or LATG), have increased rapidly during this period. (55 cases in 2001, 150 cases in 2002, and 364 cases in 2003). Laparoscopic function-preserving gastrectomies were not performed until 2003, during which year one pylorus- preserving gastrectomy and six proximal gastrectomies were performed laparoscopically. A wedge resection for a gastric submucosal tumor was performed in 71 cases in 2001, 82 in 2002, and 103 in 2003. Hand-assisted laparoscopic surgery (HALS) was performed in 39 cases in 2001, 55 in 2002, and 49 in 2003. As for personal indications for a LADG, 14 surgeons performed a LADG only for a T1 lesion, and 5 surgeons extended their indications to T2N0 lesions. In the near future, laparoscopic procedures for gastric cancer will be widely adopted in Korea if the medical-insurance obstacle is overcome and the long-term survival results are verified.