• Geomechanics and Engineering
• /
• 제15권2호
• /
• pp.805-810
• /
• 2018

The abrasivity of rocks results in tool wear in rock excavation or drilling projects. It can affect significantly the cost and schedule of the projects performed in abrasive rock massess. For this reason, the understanding of the mechanism of rock abrasivity is very important for excavation projects. This study investigates the effect of strength on the LCPC abrasivity coefficient (LAC) for igneous rocks. The LCPT test, the uniaxial compressive strength (UCS) and the Brazilian tensile strength (BTS) tests were carried out on the igneous rock samples. The abrasive mineral content (AMC) was also determined for each rock type. First, the LAC was correlated to the AMC and a very good correlation was found between the two parameters. Then, the multiple regression analysis was carried out by including the AMC, UCS and BTS to the analysis in order to infer the effect of the strength on the LAC. It was seen that the correlation coefficients of multiple regression models were greater than that of the relation between the LAC and the AMC. It is concluded that the AMC is the dominant parameter determining the abrasivity of rock. On the other hand, the rock strength has also significant effect on rock abrasivity.

• 한국건축시공학회지
• /
• 제8권5호
• /
• pp.67-73
• /
• 2008

Recent trends in construction towards larger scale and taller buildings are causing problems by ineffective existing management approach in construction industry have emerged. Delivering necessary materials and mobilizing the human resources and equipment In a timely manner to keep labor on schedule have become a critical issue to be addressed. In particular, many specialty contractors carrying out multiple projects have been experiencing difficulties mobilizing the manpower on time and in right places due to poor communication at each stage of labor supply, resulting in waste of valuable resources. Hence, it's imperative for the specialty contractors to obtain specific information on labor demand so as to set up a communication and labor management system to ensure the right human resources will be mobilized in the right place at the right time. The study therefore is aimed at developing an optimal human resources management system for specialty contractors performing multiple projects. To that end, the study is focused on rebar and concrete work. The outcome of the study is expected to help allocate the right human resources to the right place in a timely fashion, thereby achieving an effective workflow at construction sites.

• 인터넷정보학회논문지
• /
• 제17권5호
• /
• pp.121-129
• /
• 2016

Company A, an embedded system manufacturer, has been managing multiple development projects. Executives need to understand the risk level of every project and prioritize resource distribution. Traditional project monitoring tools or excel sheets are too complex for calculating the risk factors across a functional organization. Two new charts, "Spear-head Chart" and "Float Chart" were designed to assist high level decision making processes. Two charts were used for weekly executive meetings in order to monitor project progress and rectify project direction. One page graphical monitoring tools in Company A are good enough for high management decision making. Authors explain the characteristics of two charts and propose its practical implementation in real working environment. Spear-head chart was also implemented as a system.

• 대한산업공학회지
• /
• 제36권4호
• /
• pp.219-229
• /
• 2010

The PERT/CPM are considered as the base procedures for the most successful project scheduling programs. Unfortunately, it is not easy to apply these procedures to real-life projects. This is due to the fact that PERT/CPM assume an infinite number of resources for each activity in project networks. Obviously, the completion time under no constraints is less than when constraints are imposed. One way of approaching this problem is to use heuristic solution techniques. In this paper, we present three heuristics; MRU (Maximum Resource Use) rule, STU (Shortest Time Use) rule, MRUP (Max Resource Use and Period) rule for allocating resources to activities of projects under multiple resource constraints. Comparisons of the project durations show that these heuristic rules are superior to AG3 rule that has been widely used in practice (Elsayed and Boucher, 1994).

• 한국초등과학교육학회지:초등과학교육
• /
• 제19권1호
• /
• pp.71-83
• /
• 2000

This study examined the influences of science project activities based on multiple intelligences on problem solving behaviors of elementary school children. Specifically, the influences of the project activities on the problem solving skills and propensities of the children were investigated. Forty-four fifth graders were selected for the study. They performed the projects and made their products of it during five months on the units of "Weather" and "Our Body" Criteria for assessment of problem solving abilities were determined. The patterns reflected in products of the project activities were examined, then the observation of the subjects' problem solving behaviors and the interviews were performed based on the criteria. The results were analyzed through both of qualitative and quantitative approaches. In these analyses, the implementation of the science projects was found to contribute to the improvement in all sub-factors of problem solving, specially, skills associated with the propensities of problem identification and of the collection, analysis, and synthesis of data significantly increased

• 한국안전학회지
• /
• 제25권2호
• /
• pp.89-94
• /
• 2010

This study deals with the traffic accident according to the improvement projects of frequent accident locations. The objective is to analyze the impact of improvements on the accident reduction. In pursuing the above, the study gives the particular attentions to developing the models based on the data of 70 intersections improved. The main results analyzed are as follows. First, 4 multiple linear regression accident models(total, side right-angle, rear end and side stripe accident) which were statistically significant were developed. Second, total accidents reduction by sight-distance and turning traffic flow improvements, side right-angle by sight-distance, over-speed and lane operation, rear end by turning traffic flow, signal and lane operation, and side stripe by traffic impedance improvements were analyzed. Finally, the above 4 models were evaluated to be statically significant through the correlation analysis and pair-sample t-test.

• 벤처창업연구
• /
• 제18권5호
• /
• pp.159-174
• /
• 2023

본 논문에서는 효과적으로 AI 프로젝트 및 신사업을 선정할 수 있는 방법론을 제안했다. AI 기술은 다양한 산업 분야에서 기업의 비즈니스를 고도화하고 산업 전체의 부가가치를 증대시킬 수 있는 기술이다. 기업가정신 연구 분야에서도 AI 기술은 중요한 소재가 되고 있다. 기업들은 AI 기술을 이용해 새로운 비즈니스를 창업하거나 기존 기업 내에서 신사업을 추진하고 혁신을 추진한다. 그러나 기업에서 AI 프로젝트를 선정하고 추진하는 의사결정 과정에서는 다양한 제약사항과 어려움이 존재한다. 본 논문에서는 모폴로지(Morphology)와 AHP 및 TOPSIS 결합 모형을 통한 AI 프로젝트 선정의 새로운 방법론을 제안한다. 제안 방법론은 AI 기술의 기술적 타당성과 현업의 사용자 요구조건을 동시에 고려하여 AI 프로젝트를 선정할 수 있도록 도와준다. 이 연구에서는 HR 분야의 다수 AI 프로젝트를 결정하고자 하는 실제 기업에 제안 방법론을 적용하고 그 결과를 평가했다. 이를 통해 방법론의 현실 적용 가능성을 확인하였으며, 기업의 AI 프로젝트 관련 의사결정에 유용하게 활용하기 위한 방법을 제시했다. 이 연구에서 제안하는 방법론은 사내 기업가정신(Intrapreneurship) 효과를 증진시키는 차원에서, 기업이 고려하는 여러 AI 프로젝트에 대하여 합리적인 방법으로 선정에 대한 의사결정의 프레임워크를 제시한다는 점에서 의미가 크다.

• 한국임상약학회지
• /
• 제21권2호
• /
• pp.106-114
• /
• 2011

1) 제주도 사업의 경우에 고양시보다 의료기관의 참여도가 높았는데 이것은 처방내에서 혹은 동일 의사의 처방내에서 병용금기나 중복의 발생을 줄이는 노력을 기울인 사실을 의미하였다. 빈도수에 있어서 병용금기는 고양시에서 처방전 1만 건당 0.45건 발생에서 제주도는 0건으로, 중복의 경우는 고양시에서 1만 건당 197건에서 제주도는 23건으로 감소하였다. 2) 하지만 제주도의 의료기관 참여도가 높음에도 불구하고 다른 의사 처방과의 점검에서는 병용금기 및 중복이 뚜렷이 감소하지 않았다. 병용금기의 발생은 고양시에서 1만 건당 4.95건에서 제주도의 경우 4.16건으로, 중복의 경우에 고양시의 경우 1만 건당 426건에서 제주도는 381건으로 감소하였지만 그 차이는 동일 의사 점검에서와 같은 뚜렷한 감소가 아닌 미세한 것이었다. 3) 두 지역을 통합하여 계산하였을 때 병용금기 발생의 동일 의사 점검: 다른 의사 점검의 비(比)(ratio)는 1:23으로 계산되었다. 4) 고양시 지역에서 중복의 발생은 동일 의사 점검: 다른 의사 점검의 비(比)(ratio)는 1: 2.12이었으며 제주도의 경우 그 비(比)(ratio)는 1:16.5이다. 5) 병용금기나 중복의 발생 문제 대부분이 다른 의사가 발행한 복수 처방에 의한 의약품의 병용에서 비롯하는 문제이며 이것은 의도하거나 인지하지 못한다는 점에서 단순 다제병용보다 심각한 문제를 포함할 수 있다. 6) 연구의 발견점은 의료 및 약사용 측면에서 통합성을 높이는 정책대안의 시급성을 시사하고 있으며 DUR제도의 확대강화와 단골약국 이용을 통하여 이러한 목표를 향한 정책을 지지해주는 결과라고 볼 수 있다.

• Industrial Engineering and Management Systems
• /
• 제10권1호
• /
• pp.34-42
• /
• 2011

Many companies open multiple projects simultaneously due to market trends, which results in a crowding out effect because of limited resources. R&D engineers become overloaded and scheduling of product development is delayed resulting in timing misses and lost sales leads. The company in this case study (Company A), often opens up many projects simultaneously in order to respond to market needs quickly. The engineers are overloaded and, of course, the schedule is delayed. In order to identify problems, Company A began using Dr. Goldratt's Thinking Processes (TP) during new product development (NPD). When the analysis phase of TP was completed, Company A's core problem was identified as "the quantity of kick-off projects." Consequently, new rules and conditions and procedures were proposed for the opening, suspending, stopping, and closing of projects. Finally, the "Future Reality Tree" ensured that the proposed rules, conditions and procedures were set up as an available solution approved for practical application by executives. After a one-year trial run, the results showed that the Project Duration Rate was reduced by 53%, the Project Closed Rate was increased by 140% and the Project on Time Rate was increased from 10% to 68%. The above results give significant evidence of the benefits of the proposed methodology.

• 산업경영시스템학회지
• /
• 제42권1호
• /
• pp.137-142
• /
• 2019

There are two methods for evaluating two or more mutually exclusive projects. One is a total investment approach and the other is an incremental investment approach. The former can rank projects by the criterion of the net present value, but the latter can't do it. An incremental investment approach is only possible when all pairwise alternatives are compared. Thus an incremental investment approach is superior in ranking them over an incremental investment approach. To do so, a principle of comparison must be established. Comparisons of profitability are reasonable when operating the same amount of investment over the same period of time. One principle is that all projects are invested in the largest of the projects. Another principle is that all projects are invested during the longest project life of the projects. In this paper, even if the principle is followed, it will be shown that the external rate of return fails to rank them. However, the productive rate of return criterion would prove to be able to rank them like the net present value standard, provided that the principle of comparison is kept. In addition, rate of returns can be assessed so that all mutually exclusive projects can be compared at once, such as on the criterion of the net present value. That is, it can be also compared with many other returns, such as the profit rates on financial investments or real investments.