• Journal of Korean Society of Transportation
• /
• v.9 no.2
• /
• pp.41-56
• /
• 1991

The aim of this research is designing road lighting installations(arrangement, mounting height spacing and overhang) which produce a certain level and distribution of luminance together with minimal glare. These can be varied over a limited range for a given luminance and road surface to achieve the required installation performance. In Korea there are no code of practice which lays down recommended performance criteria (Lavg, Uo, Ul, G, TI) with practical design guidance on how to achieve them. In case study design rules and current installation of road lighting in daegu city are analysed. The core of research are suggesting a new performance criteria and providing a set of table giving the maximum lognitudinal spacing between successive luminaires. The result of this research prescribes the combination of height and spacing for various road widths and arrangements which will achieve a specified minimum performance on straigt roads for particular luminaire and a particular road surf-ace.

• Journal of Korean Society on Water Environment
• /
• v.28 no.2
• /
• pp.269-276
• /
• 2012

The surface characteristics and performance of PTFE (polytetrafluoroethylene) hollow fiber membranes have been systematically investigated at lab- and pilot-scale to assess their application to membrane-bioreactor, particularly for integrating wastewater reclamation and rainwater harvesting. The PTFE membrane expressed some surface features, such as hydrophobicity, which might enhance membrane fouling. However, lab-scale performance and cleaning experiments under various conditions demonstrated that the PTFE membrane could produce the desirable water flux with good cleaning efficiency, implying easy operation and maintenance due to superior chemical resistance of PTFE membranes. Most of effluent water qualities were met with Korean standard for discharge and reuse, except color. Color level was further reduced by blending with rainwater at 75:25 ratio. Based on the lab-scale experimental results, the pilot plant was designed and operated. Pilot operation clearly showed sTable performance with satisfactory water quality, suggesting that PTFE membrane could be applied for decentralized MBR integrated with rainwater use.

• Journal of Periodontal and Implant Science
• /
• v.45 no.1
• /
• pp.23-29
• /
• 2015

Purpose: This study was conducted to compare the cumulative survival rates (CSRs) and the incidence of postloading complications (PLCs) between a bone-level internal connection system (ICS-BL) and an external connection system (ECS). Methods: The medical records of patients treated with either a ICS-BL or ECS between 2007 and 2010 at Asan Medical Center were reviewed. PLCs were divided into two categories: biological and technical. Biological complications included >4 mm of probing pocket depth, thread exposure in radiographs, and soft tissue complications, whereas technical complications included chipping of the veneering material, fracture of the implant, fracture of the crown, loosening or fracture of the abutment or screw, loss of retention, and loss of access hole filling material. CSRs were determined by a life-table analysis and compared using the log-rank chi-square test. The incidence of PLC was compared with the Pearson chi-squared test. Results: A total of 2,651 implants in 1,074 patients (1,167 ICS-BLs in 551 patients and 1,484 ECSs in 523 patients) were analyzed. The average observation periods were 3.4 years for the ICS-BLs and 3.1 years for the ECSs. The six-year CSR of all implants was 96.1% (94.9% for the ICS-BLs and 97.1% for the ECSs, P=0.619). Soft tissue complications were more frequent with the ECSs (P=0.005) and loosening or fracture of the abutment or screw occurred more frequently with the ICS-BLs (P<0.001). Conclusions: Within the limitations of this study, the ICS-BL was more prone to technical complications while the ECS was more vulnerable to biological complications.

• The Journal of Fisheries Business Administration
• /
• v.16 no.1
• /
• pp.91-124
• /
• 1985

Mariculture is contrasted with inland aqua-culturing fisheries. It is defind as the Industry of rearing Aquaorganism in limited coastal area relatively shallow in depth. Then, It's coming into being realization of Mariculture in it is long in history that Mariculture was realized in Korea. But it is from the early part of 1960s, that this industry has normally developed. Owing to 200 miles economy-zone problems of coastal countries, the development of deep sea fishing was limited, so the Korean Government has now appreciated the importance of cultured industries in the field of coastal fisheries. And the Korean Mariculture the output of which was only 18, 000 M/T in '60s attained 540, 000M/T in 1980s, has now occupied its relative importance in Korean Fisheries Industry. So the purpose of this report is to suggest the prospect of technical development of mariculture in the future of Korea, through the analysis of the various problems that affect upon the individual management '||'&'||' fishing ground utilization, along with the appreciation of "how to extend of those technical innovation" and "how the fishermen's technique level is extended at this stage. According to this study, the result is summarized as follows. First, Maricultural technique is classified into 8 sub-techniques as follows, as shown in fig. 1.Fig. 1. The Formation structure of mariculture technique Second, the change of technical method of mariculture in coastal area of Korea has made as 5 stages; 1) Scattering of culturing organism 2) Culturing by putting stone and installing bamboo 3) Culturing by installing rope and seeding 4) Culturing of putting objectives in cages 5) Culturing fish by feed Third, the maricultural fisheries of Korea has about 70 years long in history. It began from 1910s. But at that time there was no special technique in aquaculture and its technique was confined in searching out the object of species. The species was laver, oyster ect.Forth, although realization of mariculture in Korea has been long time, it is of late from 1960s that this has been industrial with normal development, and its technique of mariculture has mainly has developed from 1970s. Its result not only contributed to the high growth in Korean ecconomy along with the well balanced development between industires, but also it played a great role for the resolution of nation's food problem. Especially maricultural production has shown its sustained annual increase of 13.8% during the last 20 years. So the portion of mariculture among total fisheries stucture was extended from 4.1% in the early 1960s to 22.4% in 1980s.Fifth, it could be safely said that such development in maricultural field is resulted from the activity of aquacultural institutes such as Fisheries Reseach '||'&'||' Development production of major kinds such as Oyster, Sea-mustard, and Laver etc. As well as in the innovation of aquaculturing method with synthetic fiber utilization. FRDA has played important role in the efficient propargation of new aquacultural technique.Sixth, as for the change in aquaculture structure and its during period between 1970s and 1980s, the private management participation shown 25% increase from household number of 45, 173 to 56, 268 in total number. And in the respect of the management scale, of their management decreased, while it showed an increase in relative large scale management, the increase over 3 employees compared with other fisheries field between '70s and 80s. This must be an major trait to be recorded, Now the data above mentioned are shown as in table 1 and 2.Table 1. The maricultural fishing ground development situation in 982.Table 2. The mariculture management as seen in the employmnet size in high seasion.Owing to the technical innovation, of the mariculture in coastal area new income of fishermen increased and it also is true that the number of fishermen participating in its industrialization increased. But the problem being from now on is the self-discharge of the destruction fishing ground considered resulted from rapid expansion in aquaculture industry and the preventive system of sentility of fishing ground. sentility of fishing ground.

• Korean Journal of Veterinary Service
• /
• v.35 no.4
• /
• pp.321-325
• /
• 2012

Hazard Analysis Critical Control Point (HACCP) system application is expanded to food chain from farm to table to supply safe livestock products with consumers in Korea. The objectives of this study were to analyze the HACCP operating conditions in butcher shops and to suggest for better HACCP implementation. We analyzed the HACCP inspection reports for butcher shops implemented by the Korea Livestock Products HACCP Accreditation Service from 2007 to 2009 and from 2010 to 2012 to compare the rate of HACCP non-compliances. The overall rate of non-compliances was higher in 2010~2012 than 2007~2009. The current inadequate HACCP operating level was directly related with the business size. Ninety-nine percent of the butcher shops were very small business with under 10 employees in Korea, and these small-sized businesses usually had great difficulties in implementing HACCP due to lack of technical expertise and financial resources. To overcome the obstacles and to facilitate more effective HACCP application and operation in butcher shops, government should play a leading role in developing flexible and simplified HACCP-based system which merges both the pre-requisite and HACCP principles.

• The Journal of Engineering Geology
• /
• v.26 no.1
• /
• pp.63-70
• /
• 2016

The aim of this study is the safety and an accident prevention in limestone terrain by the underground tunneling. The geology of the study area consists of a Paleozoic sedimentary sequence dominated by limestone, sandstone, shale, and carbonaceous shale. The sequence gently dips to the northeast but the joint contains steep with variable trend. A significant fracture zone is developed in the limestone and shale beds, sub-parallel to bedding, and follows in part the limestone-sandstone contact. Monitoring of groundwater levels in the area shows marked fluctuations in the water table, which repeatedly rose to a level of -4 m before sinking to -15 m. These cycles occurred in mid-May, 2007 and in early and middle June. The data indicate that these fluctuations were unrelated to rainfall that occurred during the study period. We infer that the fluctuations were associated with the development of underground karstic networks along the deep fracture zone, and overlying ground subsidence is likely related to the rapid sinking of groundwater and the associated strong downward suction force.

• Journal of the Society of Disaster Information
• /
• v.17 no.1
• /
• pp.143-153
• /
• 2021

Purpose: The purpose of this study was to analyze data from the Ministry of Health, Safety and Health and the Ministry of Employment and Labor, and the total number of deaths (disease + accidents) reached 2,020 in 2019 and the estimated economic loss was 27.6 trillion won. This is believed to be the time to present improvements to ensure that economic loss estimates are steadily increasing as in Table 1, and that government-level losses can be drastically reduced. Method: In this study, factors were selected through prior research, and reliability analysis, technical statistics and correlation analysis, and multi-term analysis were conducted through the Jamovi program for the analysis of results. Result: Multiple session analysis was conducted to verify the research theory indicated in this study, and the analysis showed that mechanical and management factors did not affect the fall death accident of the opening, and human factors, material and environmental factors had a static effect. In addition, mechanical and administrative factors do not affect the fall of the outer wall, and human and material and environmental factors have a static effect. Conclusion:: As a result of analyzing 450 falling deaths over the past 13 years among the data posted to the Korea Health and Safety Corporation, the most common causes of falling deaths were the openings and outer walls.

• Journal of Distribution Research
• /
• v.16 no.2
• /
• pp.1-24
• /
• 2011

1. Introduction: Contrast to the offline purchasing environment, online store cannot offer the sense of touch or direct visual information of its product to the consumers. So the builder of the online shopping mall should provide more concrete and detailed product information(Kim 2008), and Alba (1997) also predicted that the quality of the offered information is determined by the post-purchase consumer satisfaction. In practice, many fashion and apparel online shopping malls offer the picture information with the product on the real person model to enhance the usefulness of product information. On the other virtual product experience has been suggested to the ways of overcoming the online consumers' limited perceptual capability (Jiang & Benbasat 2005). However, the adoption and the facilitation of the virtual reality tools requires high investment and technical specialty compared to the text/picture product information offerings (Shaffer 2006). This could make the entry barrier to the online shopping to the small retailers and sometimes it could be demanding high level of consumers' perceptual efforts. So the expensive technological solution could affects negatively to the consumer decision making processes. Nevertheless, most of the previous research on the online product information provision suggests the VR be the more effective tools. 2. Research Model and Hypothesis: Presented in