In international businesses human resource elements acquired in different countries might have different values in varied industries due to different quality of education and experiences in original countries. Using existing models to evaluate expected values of human resource elements such as education and experience setc. acquired in sending countries they are expanded to examine also the values of science and engineering degrees in technology jobs with selectivity bias correction. This paper used the US census survey data of 2015 on earnings, academic degrees etc. to contrast qualitative effects with quantitative effects of human resource elements compared to those in the native and/or white group.

Mythimna separata (Lepidoptera: Noctuidae) is a notorious migratory pestand has caused significant damage in NortheastAsia including South Korea. For this reason, predicting occurrence time and distribution area considered to be an importantfor establishing early control plan. Because it cannot survive during the winter in South Korea and occurs seasonallydue to invasion from the southeast of China, general application of CLIMEX may not be adequate. Therefore, we appliedCLIMEX for analyzing seasonal occurrence M. separata of based on its growth index (GI) predicted in accordance withclimate. As a result, GI in southern region of South Korea began to occur at the earliest time and showed the highestvalue from the end of April to the beginning of September.

아스팔트 혼합물은 덤프트럭으로 운반․대기 중 단기노화(short-term aging: STA) 되므로 모든 현장혼합물은 STA후 포설된다. 따라서 실험실에서 현장에 포장된 아스팔트 혼합물의 각종 특성을 추정하려면 같은 재료로 반드시 STA 처리 후 공시체를 제조해야한다. 이것이 실험실 혼합물을 STA 처리하는 근본적인 이유이며, 실험실 STA 방법은 현장상태를 최대한 근사하게 모사(simulation) 토록 규정되어져야 한다. 그러나 국내는 물론 외국 기준도 이러한 근본적인 원리를 제대로 준수 하지 못하고 있어 기준에 제시된 대로 STA를 수행해서는 현장에 포장된 아스팔트 혼합물의 특성을 추정할 수 없다. 이를 해결하기 위한 한 가지 방법의 한 방법은 노화량(aging quantity: AQ) 모델링을 통하여 혼합물의 노화도를 추정하는 것이다. 밀입도 혼합물의 AQ 모델은 기존의 연구에 의하여 지수함수 식으로    와 같이 제시되었다. 하지만 SMA 혼합물은 바인더 함량이 높고 섬유제 등이 사용되어 밀입도와 다르므로 본 연구에서는 SMA에 대한 AQ 모델식을 개발하고 이로부터 단기노화 온도와 시간에 따른 노화도를 추정하는 연구를 수행하였다. 그러므로 본 연구의 목적은 SMA 혼합물의 단기노화도를 추정하기 위하여 기 개발된 AQ 모델을 SMA 혼합물에 적용하여 필요한 보정을 통해 SMA 혼합물의 AQ 모델로 노화도를 추정하는 방안을 제시하는 것이다. 노화도는 아스팔트 노화의 척도로는 가장 많이 쓰이는 절대점도(absolute viscosity: AV)를 이용하였으며 SMA 혼합물을 대상으로 하여 SMA 노화도 정립에 필요한 기초자료를 제시코자 한다.

강풍으로 인한 구조물의 파괴는 한계상태 이상의 풍하중으로 인한 파괴와 한계상태 보다 레벨은 낮지만 반복적인 풍하중에 의한 피로파괴로 나눌 수 있다. 한계상태설계 파괴에 대한 연구는 많이 이루어져 있으나, 강풍에 의한 피로파괴에 관한 연구는 드물다. 본 논문은 강풍에 의한 피로파괴 해석 시 사용할 수 있는 풍속의 계속시간에 관한 모델을 기상관측소로부터 획득한 자료를 사용하여 확률통계방법에 의하여 제시한 것이다. 강풍의 발생성인은 한국의 기상 특성에 따라 태풍, 전선풍, 계절풍으로 나누었고, 년최대풍 속자료에 대한 통계적인 처리는 극치Ⅰ형 누적분포함수를 사용하였다. 1회 강풍이 불었을 때 어떤 레벨에서 풍속의 계속시간은 풍속의 확률밀도함수와 최대풍속값에 의해 일반화된 누적신간의 곱으로 각 강풍의 발생성인에 따라 주어진다.

최근 백두산 화산분화의 전조현상 증가로 인해 백두산 분화의 가능성이 지속적으로 제기되고 있으며 주변국인 일본의 화산 활동 또한 활발한 추세이다. 일본 화산 및 백두산으로부터 500km 이상의 거리에 위치한 우리나라의 경우 화산 분화로부터 근접 재해의 직접적인 위험은 없으나 화산재 확산에 의한 영향을 받을 가능성이 있어 이에 대한 대책 및 대응 방안 마련이 요구되고 있는 실정 이며 이에 대한 대응 방안 중 하나로, 화산재 확산 모델을 이용하여 화산재 입자의 공간분포 예측 및 대기 중 화산재 농도와 지표면의 화산재 퇴적 두께를 예측하는 방법이 있다. 본 연구에서는 화산재 확산 예측 모형에 의해 도출된 대기 중의 화산재 농도와 낙하 화산재 퇴적 두께를 이용하여 한반도 근역에 대하여 화산재 공간 확산 확률 및 낙하 확률 분석 기법을 제시하고 우리나라 17개 광역지자체에 대한 분석을 수행하였다.

In pelagic longline, deploying the gear such that the depth of the hook is the same as that of the target fish is important to improve the fishing performance and selectivity. In this study, the depth of the tuna longline hook was estimated using the mass-spring model, catenary curve method, and secretariat of the pacific commission Pythagorean method in order to improve the performance of the longline gear in Fiji. The former two methods were estimated to be relatively accurate, and the latter showed a large error. Further, the mass-spring model accounted for the influence of tidal current in the ocean, which was found to be appropriate for use in field trials.

Recycling is required for all disused vehicle since 2015. The resource recycling act also recommends that most disused vehicle parts have to be reused except for steering and brake parts. Since vehicle windshields should provide protection for drivers and passengers, they need high structural strength and reliability. However, the vehicle windshields themselves contain many defects arising from glass production process. Because the vehicle windshields are exposed to harsh road conditions, they are expected to experience the formation and growth of surface cracks, which can result in sudden failure. In this study, equibiaxial flexural strength tests are performed on used vehicle windshields to examine whether or not the parts can endure high impact stress due to foreign flying objects. The following conclusions can be drawn: (1) The equibiaxial flexural strength of used vehicle windshields fits the two-parameter Weibull distribution. The equibiaxial flexural strength with a 99.9% failure probability is 69MPa for used vehicle windshields. (2) The equibiaxial flexural strength with six sigma quality level and maximum principal stress at vehicle windshield under high impact load are 8.05MPa and 23MPa respectively. Therefore, Structural safety factor of used vehicle windshields is 0.35 and so we should prohibit used vehicle windshields from keeping in reuse.

대동여지도의 지도학적 특성에 대한 연구가 상당히 이루어졌음에도 불구하고 투영법에 대한 체계적이고 종합적인 연구는 드문 편이다. 이 연구의 주된 목적은 GIS 분석에 기초하여 대동여지도의 투영법을 추정하고, 그 특성을 파악하는 것이다. 이를 위해 먼저 대동여지도와 같은 고지도에 대한 투영법 추정의 절차와 GIS 기반의 분석 방법을 정립하였다. 핵심적인 과정은 각 후보 투영법을 적용한 준거 지도 상의 통제점을 고지도 상의 좌표로 기하변환한 후 고지도와의 위치 일치도와 형태 일치도를 분석하는 과정을 모든 후보 투영법에 반복적으로 수행하여 가장 적합도가 높은 투영법을 선정하는 것이다. 13종의 후보 투영법에 대해 다양한 투영 기준선을 적용하여 대동여지도의 투영법을 추정한 결과 정형원추도법 혹은 정형원통도법의 적합성이 가장 높은 것으로 나타났다. 하지만 오차의 분포가 이질적으로 존재하는데, 남부는 상당히 오차가 작은 반면 북쪽으로 갈수록 위치 오차와 형태 오차가 증가되었다. 따라서 남북 간에 적합한 투영법이 서로 다를 것으로 간주하고, 대동여지도의 북부와 남부에 대한 분석을 별도로 수행하였다. 그 결과 대동여지도의 북부는 정적원통도법이, 남부는 정거원추도법 및 정형원추도법의 적합도가 가장 높았으나, 남부의 경우 투영법 간에 적합도의 차이가 크지 않았다. 이 연구는 고지도에 대한 GIS 분석 연구의 확대에 기여한다는 의의가 있으나 향후 적합도를 측정하는 방법의 개선이나 통제점의 검증 등이 필요하다.

PURPOSES :This study was initiated to estimate the utilities of usage attributes of BRT and Bimodal Trams using a conjoint analysis method in order to identify the important features pertaining to the use of BRT and Bimodal Trams.METHODS :For this purpose, important attributes and those level in the use of BRT and Bimodal Trams in the city of Sejong were identified. Next, a profile questionnaire pertaining to BRT and Bimodal Trams was designed for the conjoint analysis, and a survey was conducted in the city of Sejong. Using SPSS software, conjoint analysis was performed to identify the important attributes vis｀-a-vis the use of BRT and Bimodal Trams in the city of Sejong. Finally, the utilities for individual attributes were calculated based on the models estimated by the conjoint analysis.RESULTS :The results of the conjoint analysis were used to identify the important attributes. With regard to the usage of BRT, users indicated that fare was the most important attribute with the highest utility. In the case of Bimodal Trams, the users indicated that the number of seats and internal environment were the most important attributes with the highest utilities.CONCLUSIONS :Based on the results of the conjoint analysis, the important attributes pertaining to the use of BRT and Bimodal Trams in the city of Sejong were identified. Our study indicates that BRT in the city of Sejong needs to be upgraded to improve the utilities of the important attributes. Currently, Bimodal Trams has not been introduced completely in the city of Sejong. However, in the future, when the introduction of Bimodal Trams is completed, the important attributes should be emphasized in order to improve the quality of its service.

Liquid storage tank is one of the major infrastructures and generally used to store gases, drinking and utilizing water, dangerous fluids, fire water and so on. According to the recent reports and experiences, the tank structures are damaged in many earthquakes due to their low energy dissipating capacity. Therefore, many researchers have been tried to know the dynamic properties of the tanks including liquids. However, vary limited experimental studies are carried out using relatively small tank models. In this study, a series of shaking table tests are performed with maximum 2 m cubic rectangular liquid storage tanks made of steel to measure the natural frequency and estimate damping coefficient of impulsive and convective mode of the tanks. Especially, the damping values under different shapes and excitation methods are estimated by logarithmic decrement method and half power band-pass method and compared with current design code and standards such as ASCE 7, Eurocode 8 and NZS. Test results show that the impulsive mode damping is around 2% which is proposed by general standards and codes but the impulsive mode damping is 0.13% average that is slightly lower than the code recommendation.

The paper presents a new short-term dynamic displacement estimation method based on an acceleration and a geophone sensor. The proposed method combines acceleration and velocity measurements through a real time data fusion algorithm based on Kalman filter. The proposed method can estimate the displacement of a structure without displacement sensors, which is typically difficult to be applied to earthquake or fire sites due to their requirement of a fixed rigid support. The proposed method double-integrates the acceleration measurement recursively, and corrects an accumulated integration error based on the velocity measurement, The performance of the proposed method was verified by a lab-scale test, in which displacement estimated by the proposed method are compared to a reference displacement measured by laser doppler vibrometer (LDV).

This paper was to evaluate social enterprises’ management efficiency with Data Envelope Analysis (DEA). The data was based on the 168 social enterprises’ of annual performance reports published in 2015. The research focused on to measure both financial efficiency and social impact of the companies simultaneously. To apply DEA, the paper classified the enterprises into seven types based on types of socal impacts which each company provides before the estimation of the efficiency. The research results showed that group D, which employes disadvantaged people, provides social services and shares resources was the most efficient group and had higest net worths in Pure Technical Efficiency. In contrast, Group B, which only employs social advantage people and provides social service, was the least efficient one. The research suggests a practical and efficient framework in measuring social enterprises’ management efficiency, including both the financial performance and social impacts simultaneously with their self-publishing reports. Because the Korea Social Enterprise Promotion Agency does not open business reports which social enterprises submit each year, there are basic limitations on researchers attempting to analyse with data from all social enterprises in Korea. Thus, this study dealt with only 10% of the social enterprises which self-published their performance report on the Korea Social Enterprise Promotion Agency’s web site. Regardless of these limitations, this study suggested substantial methods to estimate management efficiency with the self-published reports. Because self-publishing is increasing each year, it will be the main source of information for researchers in examining and evaluating social enterprises’ financial performance or social contribution. The research suggests a practical and efficient framework in measuring social enterprises’ management efficiency, including both the financial performance and social impacts simultaneously with their self-publishing reports. The research results suggest not only list of efficient enterprises but also methods of improvement for less efficient enterprises.

건축구조기준(KBC-2016)에서는 팔각기둥 형상을 가진 구조물의 풍력계수는 형상비 25이상에서 1.4로 일정한 값을 적용하도록 하고 있다. 하지만 팔각뿔 형상인 첨탑 구조물은 팔각기둥과는 그 형상이 다르기 때문에 첨탑 구조물에 적용할 풍력계수에 관한 연구가 필요하다. 본 논문에서는 풍동실험을 이용하여 첨탑 구조물의 형상비 변화에 따른 풍력계수 특성을 규명하였다. 일반적으로 구조물에 작용하는 풍력계수는 형상비가 증가할수록 커진다. 하지만 특정 형상비를 초과하면 풍력계수는 더 이상 증가하지 않고 일정하게 수렴한다. 이러한 특성을 반영하기 위해, 예비실험은 형상비가 10~19.2인 모델에 대해 수행하였고, 풍력계수가 수렴하기 시작하는 형상비를 검토하였다. 그 결과 15 이상의 형상비에서 풍력계수가 약 1.1로 수렴하는 것으로 나타났다. 형상비 변화에 따른 풍력계수 변화를 고찰하기 위해 형상비 3~8.5 까지의 모형을 추가 제작하여 풍동실험을 수행하였다. 연구의 결과를 이용하여 형상비 변화에 따른 풍력계수의 변화를 경험식으로 제안하였고, 추세한 값들이 실험값 보다 작지 않도록 보정하였다.

The purpose of this study is to estimate conservation value of fisheries resource protected area by the doublebounded dichotomous choice contingent valuation method. The data in this analysis come from a survey of respondents of resident in fisheries resource protected area using a proportional stratified sampling from the population. The questionnaires covered all the 5 fisheries resource protected area and the sample size of every protected area was 120 questionnaires. The survey period was from August to October in 2016. Above all, the average willingness to pay amount(WTP) per person of Namhae-Tongyoung Ⅰ, Namhae- Tongyoung Ⅱ, Jindong bay, Hansan bay, Cheonsu bay is estimated ￦6,215, ￦13,215, ￦6,405, ￦9,785, and ￦10,390 respectively. And, the total value of Namhae-Tongyoung Ⅰ, Namhae-Tongyoung Ⅱ, Jindong bay, Hansan bay, and Cheonsu bay is evaluated ￦108.8 billion, ￦357 billion, ￦118 billion, 210.2 billion, ￦ 245.8 billion respectively. Moreover, the yearly value of Namhae-Tongyoung Ⅰ, Namhae-Tongyoung Ⅱ, Jindong bay, Hansan bay, and Cheonsu bay is evaluated ￦6 billion, ￦19.6 billion, ￦6.5 billion, 11.6 billion, ￦ 13.5 billion. In conclusion, fisheries resource protected area has the higher conservational value. Consequently, it is essential for now or future generation's use of fisheries resources. In light of the fisheries resource protected area's value and importance, this should be promoted to the public including the local community who utilizes fisheries resource protected area wisely. Also, this suggests that the policy for fishery resource's creation and management is needed in fisheries resource protected area.

This paper validates a system identification method using mathematical optimization using sea trial measurement data as a benchmark. A fast time simulation tool, SIMOPT, and a Rheinmetall Defence mathematical model have been adopted to conduct initial hydrodynamic coefficient estimation and simulate ship modelling. Calibration for the environmental effect of sea trial measurement and sensitivity analysis have been carried out to enable a simple and efficient optimization process. The optimization process consists of three steps, and each step controls different coefficients according to the corresponding manoeuvre. Optimization result of Step 1, an optimization for coefficient on x-axis, was similar compared to values applying an empirical regression formulae by Clarke and Norrbin, which is used for SIMOPT. Results of Steps 2 and 3, which are for linear coefficients and nonlinear coefficients, respectively, was differ from the calculation results of the method by Clarke and Norrbin. A comparison for ship trajectory of simulation results from the benchmark and optimization results indicated that the suggested stepwise optimization method enables a coefficient tuning in a mathematical way.