• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.17 no.5
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• pp.77-87
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• 2018

Traffic Density is the most important of the three primary macroscopic traffic stream parameters, because it is most directly related to traffic demand(Traffic Engineering, 2004). It is defined as the number of existing vehicles within a given distance at a certain time. However, due to weather, road conditions, and cost issues, collecting density directly on the field is difficult. This makes studies of density less actively than those of traffic volume or velocity. For these reasons, there is insufficient attempts on divers collecting methods or researches on the accuracy of measured values. In this paper, we used the 'Density Measuring System' based on the synthesise technology of several camera images as a method to measure density. The collected density value by the 'Density Mesuring System' is selected as the true value based on the density define, and this value was compared with the density calculated by the traditional measurement methods. As a result of the comparison, the density value using the fundamental equation method is the closest to the true value as RMSE shows 1.8 to 2.5. In addition, we investigated some issues that can be overlooked easily such as the collecting interval to be considered on collecting density directly by calculating the moment density and the average density. Despite the actual traffic situation of the experiment site is LOS B, it is difficult to judge the real traffic situation because the moment density values per second are observed max 16.0 (veh/km) to min 2.0 (veh/km). However, the average density measured for 15 minutes at 30-second intervals was 8.3-7.9 (veh/km) and it indicates precisely LOS B.

• Korean Journal of Environmental Biology
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• v.34 no.1
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• pp.30-36
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• 2016

We investigated the diversity pattern of spring moths across two regions of South Korea, Yongin city (middle part) and Muan gun (southern part) and the effects of climatic variables on moth species richness and abundance. Moths were weekly collected using UV light trap in April from 2013 to 2015. Climatic factors included growth degree day with base temperature 8 (GDD8), average temperature, precipitation, duration of sunshine, wind speed, and snow cover. The climatic effects on moth species richness and abundance were analyzed by short (0~3 weeks before collecting) and long (4~12 weeks before collecting) time periods, respectively. The diversity of spring moths showed the similar pattern of species composition at family level. However the dominant family differed depending on the region: Geometridae at middle part and Noctuidae at southern part. In addition the dominant species of Noctuidae occurred early in April and that of Geometridae moths occurred later in April. Three short-term climatic factors, GDD8, duration of sunshine, and precipitation one week before collecting were significant on moth species richness and abundance, while only one long-term climatic factor, temperature four weeks before collecting was significantly affected on moth species richness. We found that both Geometridae and Noctuidae were dominant in spring moth fauna across South Korea and they were different in the dominance and flying time in April. The occurrences of spring moths were largely affected by warmness and precipitation. The current global warming could affect the occurrence of spring moths and this should be monitored consistently.

• Journal of Embryo Transfer
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• v.11 no.3
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• pp.249-258
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• 1996

To improve the efficiency of in vitro production of embryos with follicular oocytes in Korean Native cows, the recovery rates, in vitro maturation, fertilization and development, and the time required for collecting and processing oocytes by aspiration with or without slicing were evaluated comparatively. The ovaries were obtained from a local abattoir and placed in physiological saline at 25~28$^{\circ}C$ and brought to the laboratory within 3 hrs. The oocytes were collected by aspiration of follicles(2~6mm) with or without slicing ovaries after aspiration, and classified into Grade I, Grade II, Denuded, Expanded oocytes by the morphology of cumulus cells attached and the homogeneity of cytoplasmic granules. Also the time required for each step of collecting and processing oocytes were measured. The cumulus cells were removed in some Grade I oocytes to measure their size and nuclear configuration before and after in vitro maturation. The Grade I oocytes were matured in vitro(IVM) for 24 hrs. in TGM-199 supplemented with 35$\mu$g /ml FSH, 10$\mu$g /ml LH, 1 $\mu$g /ml at 39$^{\circ}C$ under 5% C02 in air. They were fertilized in vitro(IVF) by epididymal spermatozoa treated with heparin for 24hrs. and then the zygotes were cocultured in vitro (IVC) with bovine oviductal epithelial cells for 10 days. The results obtained were as follows: The number of oocytes recovered per ovary was averaged 6.6 by aspiration and 11.2 by slicing post aspiration, which summed to 17.8. The number of Grade I oocytes recovered per ovary was averaged 3.1 by aspiration and 3.6 by slicing, which summed to 6.7. The percentage of Grade I to total oocytes recovered was significantly(P<0.05) higher as 48.0 % in aspiration than 31.6% in slicing post aspiration. The time requlred for recovering a Grade I oocyte by aspiration and slicing was 1.1 and 2.5 min, respectively. The mean diameter of Grade I oocytes by aspiration and slicing was similar as 148.7 and 151.5$\mu$m, respectively. The percentage of Metaphase II stage oocytes after IVM for 24 hours was significantly (P

• Asian-Australasian Journal of Animal Sciences
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• v.9 no.4
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• pp.371-374
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• 1996

Experiments were conducted to determine the effect of time intervals between collecting and use of cattle faeces as a source of micro-organisms in in vitro digestibility assays of forages. The results suggested that temperature conservation capacity by faeces depended on the size of the sample. There was no significant difference(p>0.05) between the first (T1 or 08:30 h) and second using time (T2 or 10:30 h). In vitro organic matter digestibility was significantly lower when faeces was used 5 h (T3 or 13:30 h) after collection. However, the organic matter digestibility determined at the second using time (T2) and third using time (T3) were highly correlated ($R^2=0.99$) with the first using time. It was concluded that faeces can be used as a source of microorganisms for in vitro digestibility assays of forages even 5 h after being voided.

• Journal of the Korean Society of Food Culture
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• v.34 no.4
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• pp.432-439
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• 2019

The purpose of this study is to measure the effect of customers' waiting time on their revisit intention through their emotion. Also this study assessed the effect of restaurant selection attributes on consumers' revisit intention in Korea. This study used experimental scenario questionnaires for collecting data. Frequency analysis, Cronbach's alpha, correlation, t-tests and multiple regression analysis were assessed using SPSS. Customers preferred taste, sanitation and service when selecting a restaurant to dine out. The results of this study found that there were no significant differences between positive and negative emotions due to waiting time. Findings of this study suggested that waiting time, convenience, nutritional value, and emotion influenced consumers' revisit intention. Therefore, reducing waiting time and providing proper service will help consumers have positive emotions to return to dine at a restaurant.

• Korean Journal of Construction Engineering and Management
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• v.5 no.1 s.17
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• pp.114-123
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• 2004

Contract time determination for highway construction projects has never been easy despite considerable research efforts from academia as well as industry. High variations in crew production rates are considered one of the main barriers to accurate contract time determination. This paper presents a methodology for collecting field information on crew production rates which will help to enhance the accuracy of contract time determination for highway bridge construction. Based on a standard data collection tool developed, data on field crew production rates was collected from 14 on going projects in Texas, USA, over the past two years. The production rates based on the data collected were considered by industry practitioners to be more realistic and practical than those available to the current practices. As more data becomes available, key drivers influencing production rates could be identified and provide site personnel with a means to better plan and control production in a project specific context.

• IEMEK Journal of Embedded Systems and Applications
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• v.2 no.2
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• pp.95-100
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• 2007

Recently ubiquitous application services are developed plentifully using RFID techniques in the field of distribution and security industries. However, except these field the applications using RFID are not mature yet. In this study, we proposed a real-time context service model of the u-conference based on the real-time contextual information acquired from conference and exposition. With collection of real-time contextual information for u-conference, the model can provide a lot of information services on the state of session attendee, doorway control, affairs, user certification, presentation progress etc. For the verification of proposed real-time context service model of u-conference, we design and implement the conference progress state service included the state of session attendee, user certification and presentation progress etc. This service provides the presentation state information included the current presenter, the paper list, the number of session attendee, the schedule and place of each session using the collecting RFID tag and the related information.

• International conference on construction engineering and project management
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• 2015.10a
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• pp.10-14
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• 2015

Unsafe behavior is one of the major causes of construction accidents. Managing the behavior of workers in real-time is difficult and requires huge manpower. In this paper, a new real-time locating framework is proposed to improve safety management by collecting and analyzing data describing the behavior of workers to identify habits that may lead to accidents. The aim of the study is to identify working habits of workers based on their location history. Location data is used to compare with that of other workers and equipment. The results indicate that the reuse of real-time location data can provide extra safety information for safety management and that the proposed system has the potential to prevent struck-by accidents and caught-in between accidents by predicting unwanted interaction between workers and equipment. This adds to current research aimed at automating construction safety to the point where the continuous monitoring, managing and protection of site workers on site is possible.

• Journal of Advanced Navigation Technology
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• v.20 no.1
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• pp.86-92
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• 2016

Recently, solar module is installed in crowded areas to offers services so that people can charge their smartphones or tablets. However, the burden in terms of cost is high to install in areas where utilization ratio is low and installation is difficult in limited spaces. In this paper, a system for collecting and providing the optical power is proposed from the analysis about the person that receives service in each area using the real-time data provided by the state and collected from the actual environment as well as considering the waiting time and the solar charging time in different environments. As a result, This study shows that charge was not delayed since collecting power exceeds charging power. Smartphone was fully charged in ninety-five minutes. we confirmed that with one smartphone, it can be charged a approximately fifty percent of the battery in between ten to twenty minutes, with multiple units they can be charged a approximately twenty percent of the battery in between ten to twenty minutes.

• Journal of the Korea Society of Computer and Information
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• v.25 no.10
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• pp.59-67
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• 2020

With the development of wearable devices, individuals' health status can be checked in real time and risks can be predicted. For example, an application has been developed to detect an emergency situation of a patient with heart disease and contact a guardian through analysis of health data such as heart rate and electrocardiogram. However, health data is seriously damaging when it is leaked as it relates to life. Therefore, a method to protect personal information is essential in collecting health data, and this study proposes a method of collecting data while protecting the personal information of the data owner through a LDP(Local Differential Privacy). The previous study introduced a technique of transmitting feature point data rather than all data to a data collector as an algorithm for searching for fixed k feature points. Next, this study will explain how to improve the performance by up to 75% using an algorithm that finds the optimal number of feature points k.