• Title/Summary/Keyword: Delivery Ratio

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An Efficient Secure Routing Protocol Based on Token Escrow Tree for Wireless Ad Hoc Networks (무선 애드 혹 네트워크에서 보안성을 고려한 Token Escrow 트리 기반의 효율적인 라우팅 프로토콜)

  • Lee, Jae Sik;Kim, Sung Chun
    • KIPS Transactions on Computer and Communication Systems
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    • v.2 no.4
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    • pp.155-162
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    • 2013
  • Routing protocol in ad hoc mobile networking has been an active research area in recent years. However, the environments of ad hoc network tend to have vulnerable points from attacks, because ad hoc mobile network is a kind of wireless network without centralized authentication or fixed network infrastructure such as base stations. Also, existing routing protocols that are effective in a wired network become inapplicable in ad hoc mobile networks. To address these issues, several secure routing protocols have been proposed: SAODV and SRPTES. Even though our protocols are intensified security of networks than existing protocols, they can not deal fluidly with frequent changing of wireless environment. Moreover, demerits in energy efficiency are detected because they concentrated only safety routing. In this paper, we propose an energy efficient secure routing protocol for various ad hoc mobile environment. First of all, we provide that the nodes distribute security information to reliable nodes for secure routing. The nodes constitute tree-structured with around nodes for token escrow, this action will protect invasion of malicious node through hiding security information. Next, we propose multi-path routing based security level for protection from dropping attack of malicious node, then networks will prevent data from unexpected packet loss. As a result, this algorithm enhances packet delivery ratio in network environment which has some malicious nodes, and a life time of entire network is extended through consuming energy evenly.

Analysis of Soil Erosion and Sediment Yields at the Doam-dam Watershed considering Soil Properties from the Soil Reconditioned Agricultural Fields using SATEEC System (SATEEC 시스템을 이용한 객토 토양의 토성고려에 따른 도암댐 유역의 토양유실 및 유사량 분석)

  • Yoo, Dongsun;Ahn, Jaehun;Yoon, Jongsuk;Heo, Sunggu;Park, Younshik;Kim, Jonggun;Lim, Kyoung Jae;Kim, Ki-sung
    • Journal of Korean Society on Water Environment
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    • v.23 no.4
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    • pp.518-526
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    • 2007
  • There have been serious soil erosion and water pollution problems caused by highland agriculture practices at Doam-dam watershed. Especially agricultural activities, chemical and organic fertilizer and pesticide applications, soil reconditioning to maintain soil fertility are known as primary causes of soil erosion and water qaulity degradation in the receiving water bodies. Among these, soil reconditioning can accelerate soil erosion rates. To develop soil erosion prevention practices, it is necessary to estimate the soil erosion from the watershed. Thus, the Universal Soil Loss Equation (USLE) model has been developed and utilized to assess soil erosion. However, the USLE model cannot be used at watershed scale because it does not consider sediment delivery ratio (SDR) for watershed application. For this reason, the Sediment Assessment Tool for Effective Erosion Control (SA TEEC) was developed to assess the sediment yield at any point in the watershed. The USLE-based SA TEEC system can estimate the SDR using area-based SDR and slope-based SDR module. In this study, the SATEEC system was used to estimate soil erosion and sediment yield at the Doam-dam watershed using the soil properties from reconditioned agricultural fields. Based on the soil sampling and analysis, the US LE K factor was calculated and used in the SA TEEC system to analyze the possible errors of previous USLE application studies using soil properties from the digital soil map, and compared with that using soil properties obtained in this study. The estimated soil erosion at the Doam-dam watershed without using soil properties obtained in the soil sampling and analysis is 1,791,400 ton/year (123 ton/ha/year), while the soil erosion amount is 2,429,900 ton/year (166.8 ton/ha/year) with the use of soil properties from the soil sampling and analysis. There is 35 % increase in estimated soil erosion and sediment yield with the use of soil properties from soil reconditioned agricultural fields. Since significant amount of soil erosion are known to be occurring from the agricultural fields, the soil erosion and sediment yield from only agricultural fields was assessed. The soil erosion rate is 45.9 ton/ha/year without considering soil properties from soil reconditioned agricultural fields, while 105.3 ton/ha/year after considering soil properties obtained in this study, increased in 129%. This study shows that it is very important to use correct soil properties to assess soil erosion and sediment yield simulation. It is recommended that further studies are needed to develop environment friendly soil reconditioning method should be developed and implemented to decrease the speed of soil erosion rates and water quality degradation.

Optimization Model for the Mixing Ratio of Coatings Based on the Design of Experiments Using Big Data Analysis (빅데이터 분석을 활용한 실험계획법 기반의 코팅제 배합비율 최적화 모형)

  • Noh, Seong Yeo;Kim, Young-Jin
    • KIPS Transactions on Computer and Communication Systems
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    • v.3 no.10
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    • pp.383-392
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    • 2014
  • The research for coatings is one of the most popular and active research in the polymer industry. For the coatings, electronics industry, medical and optical fields are growing more important. In particular, the trend is the increasing of the technical requirements for the performance and accuracy of the coatings by the development of automotive and electronic parts. In addition, the industry has a need of more intelligent and automated system in the industry is increasing by introduction of the IoT and big data analysis based on the environmental information and the context information. In this paper, we propose an optimization model for the design of experiments based coating formulation data objects using the Internet technologies and big data analytics. In this paper, the coating formulation was calculated based on the best data analysis is based on the experimental design, modify the operator with respect to the error caused based on the coating formulation used in the actual production site data and the corrected result data. Further optimization model to correct the reference value by leveraging big data analysis and Internet of things technology only existing coating formulation is applied as the reference data using a manufacturing environment and context information retrieval in color and quality, the most important factor in maintaining and was derived. Based on data obtained from an experiment and analysis is improving the accuracy of the combination data and making it possible to give a LOT shorter working hours per data. Also the data shortens the production time due to the reduction in the delivery time per treatment and It can contribute to cost reduction or the like defect rate reduced. Further, it is possible to obtain a standard data in the manufacturing process for the various models.

Neoadjuvant Chemotherapy and Prognosis of Pregnancy-Associated Breast Cancer: A Time-Trends Study of the Korean Breast Cancer Registry Database

  • Bae, Soo Youn;Kim, Ku Sang;Kim, Jeong-Soo;Lee, Sae Byul;Park, Byeong-Woo;Lee, Seok Won;Lee, Hyouk Jin;Kim, Hong Kyu;You, Ji-Young;Jung, Seung Pil;Korean Breast Cancer Society
    • Journal of Breast Cancer
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    • v.21 no.4
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    • pp.425-432
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    • 2018
  • Purpose: Pregnancy-associated breast cancer (PABC) is rare, and its cause and prognosis are not well known. Additionally, treatment is limited with respect to the risk to the fetus. The purpose of this study was to investigate the characteristics and treatment trends of PABC and the survival rate according to the treatment. Methods: In the Korean Breast Cancer Society Registry database, women younger than 50 years and who were diagnosed with breast cancer from 1996 to 2015 were included. PABC was defined as breast cancer diagnosed during pregnancy or within 1 year after delivery. Results: We examined 411 patients with PABC and 83,381 patients with non-PABC. Over time, the proportions of patients undergoing breast-conserving surgery and sentinel lymph node biopsy increased, and neoadjuvant chemotherapy and radiation therapy administration rates also increased. In the past, the overall survival of patients with PABC was poorer than that of patients with non-PABC, but there was no difference in overall survival rates in more recent years. There was no difference in overall survival rates between patients who received neoadjuvant chemotherapy (hazard ratio [HR], 1.28; 95% confidence interval [CI], 0.66-2.49; p=0.459), but PABC conferred poorer prognosis than non-PABC in patients receiving adjuvant chemotherapy (HR, 1.63; 95% CI, 1.27-2.08; p<0.001). Conclusion: There was no difference in the prognosis between patients with PABC and those with non-PABC receiving neoadjuvant chemotherapy. The increase in neoadjuvant chemotherapy according to current treatment guidelines is expected to improve the survival rate of patients with PABC.

A Needs Assessment of People with Hearing Impairment for Hearing Augmentation Technology Development: Focusing on Risk Context Awareness Communication (청각증강 기술 개발을 위한 청각장애인의 욕구조사: 위험상황 인식 및 의사소통 분야를 중심으로)

  • Lee, Jun Woo;Lee, Hyuna;Bach, Jong Mie
    • 재활복지
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    • v.22 no.3
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    • pp.225-257
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    • 2018
  • The purpose of this study is to find the application point of hearing augmentation technology development through examining the risk context experience of people with hearing impairment and the use of assistive device used as an alternative technology. Data of 355 people with hearing impairment with official disability grading was analyzed. The results of this study are first, research participants had no experience of recognizing any sound or vibration in situations highest in the order of means of transportation, material, and nature. Especially the ratio of being unable to recognize the sound and vibration of means of transportation was high, which implies the high possibility of people with hearing impairment experiencing risk. Secondly, the risk context that people with hearing impairment will most likely to experience are highest in the order of traffic accident, pedestrian accident, and daily life at home. Thirdly, the recognition of 2G phone/smart phone, vibrating digital alarm clock, light bar, vibrating wrist watch as assistive device for risk context awareness and notification was high and the satisfaction level of 2G phone/smart phone was the highest. Fourthly, the research participants had high recognition of assistive device for communication in the order of hearing aid, smart phone, videophone, cochlear implant and 2G phone and it was found that the satisfaction level and communication improvement level was the highest using the smart phone. Lastly, for the development of hearing augmentation technology the research participants recognized the importance of portable/wear convenience, price, and motion accuracy and for notification delivery means they preferred the method of using sight(text and light). Based on the results of this study policy and practical plans for hearing augmentation technology development for people with hearing impairment in risk context are proposed.

A Method for Reducing Path Recovery Overhead of Clustering-based, Cognitive Radio Ad Hoc Routing Protocol (클러스터링 기반 인지 무선 애드혹 라우팅 프로토콜의 경로 복구 오버헤드 감소 기법)

  • Jang, Jin-kyung;Lim, Ji-hun;Kim, Do-Hyung;Ko, Young-Bae;Kim, Joung-Sik;Seo, Myung-hwan
    • Journal of IKEEE
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    • v.23 no.1
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    • pp.280-288
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    • 2019
  • In the CR-enabled MANET, routing paths can be easily destroyed due to node mobility and channel unavailability (due to the emergence of the PU of a channel), resulting in significant overhead to maintain/recover the routing path. In this paper, network caching is actively used for route maintenance, taking into account the properties of the CR. In the proposed scheme, even if a node detects that a path becomes unavailable, it does not generate control messages to establish an alternative path. Instead, the node stores the packets in its local cache and 1) waits for a certain amount of time for the PU to disappear; 2) waits for a little longer while overhearing messages from other flow; 3) after that, the node applies local route recovery process or delay tolerant forwarding strategy. According to the simulation study using the OPNET simulator, it is shown that the proposed scheme successfully reduces the amount of control messages for path recovery and the service latency for the time-sensitive traffic by 13.8% and 45.4%, respectively, compared to the existing scheme. Nevertheless, the delivery ratio of the time-insensitive traffic is improved 14.5% in the proposed scheme.

A Study on the Liquid Crystal Formed in PLO Gel Containing Ceramide NP (Ceramide NP 를 함유한 PLO Gel 에서 형성되는 액정에 관한 연구)

  • Heo, Min Geun;Yoon, Kyung-Sup
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.47 no.1
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    • pp.85-92
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    • 2021
  • The stratum corneum is formed from keratinocytes and intercellular lipids, with ceramide as the main component of intercellular lipids. Ceramides are one of the important components of the intercellular lipids to form a lamellar structure, but they are insoluble and therefore are not suitable for direct application to the skin. Thus, it was intended to apply ceramide to the formulation of pluronic lecithin organogel (PLO gel), which received constant attention among drug delivery systems. A suitable oil for formulation was selected and a PLO gel containing ceramide was manufactured. Liquid crystal formation and variation were observed using polarized microscopes, and viscoelastic analysis was performed to find out the viscoelastic behavior of the PLO gel. Small-angle X-ray scattering (SAXS) and wide-angle X-ray scattering (WAXS) analysis were performed to confirm the structures in the formulation. Results showed that the size and stability of the liquid crystal differed depending on the content ratio of ceramide and lecithin in the PLO gel containing ceramide. Furthermore, viscoelastic analysis showed the stability of the formulation, and SAXS/WAXS analysis confirmed that the PLO gel without ceramide had hexagonal structure of the quadrilateral system array, and the PLO gel with ceramide had the lamellar structure of the quadrilateral system array.

A Study on the Derivation of Plans for Operational Improvement Based on the Analysis of the Current Status and Cases of the National Policy Research Portal (NKIS) (국가정책연구포털(NKIS) 현황 및 사례 분석을 통한 운영 개선 방안 도출에 관한 연구)

  • Noh, Younghee;Chang, Inho;Kang, Ji Hei;Kwak, Woojung
    • Journal of Korean Library and Information Science Society
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    • v.53 no.1
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    • pp.55-79
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    • 2022
  • In this study, the current status of operation was analyzed with a view to analyze the areas in need of improvement and the status of portals of similar institutions. Based on which, a proposal was made to help improve the function of utilization as well as search the products of studies by and for the research institutes funded by the government having jurisdiction by applying the information service technology developing in line with the fourth industrial revolution for the purposes of aiding and fostering with efficiency toward achieving the goal of establishment for such institutes, while strengthening the utility of NKIS. First, in order to secure the membership, it is necessary to find the targets for policy information and promotion, and it is also necessary to increase the demand for policy information, such as by preparing the people friendly policy reports, infographics, and information delivery in an easy manner. Second, it is necessary to provide customized services in the manner which reinforces reports and policy data on the social issues and education topics, which are among the interests of the primary user base by considering the ratio of visiting occupations. Third, for the diversification and expansion of video data services, it is necessary to prepare alternatives, such as by setting regulations and encouraging the institutions of jurisdiction to upload the video data. Fourth, it will be necessary to improve the overall public relations service. It is also necessary to proceed with the NKIS' publicity webtoon serialization with the latest contents or abolish the current webtoon promotion, while it is necessary to derive the plans for the efficient implementation of the contest, further to the need to discuss the secondary publicity after the contest rather than halting after it.

A Study on the Fraud Detection in an Online Second-hand Market by Using Topic Modeling and Machine Learning (토픽 모델링과 머신 러닝 방법을 이용한 온라인 C2C 중고거래 시장에서의 사기 탐지 연구)

  • Dongwoo Lee;Jinyoung Min
    • Information Systems Review
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    • v.23 no.4
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    • pp.45-67
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    • 2021
  • As the transaction volume of the C2C second-hand market is growing, the number of frauds, which intend to earn unfair gains by sending products different from specified ones or not sending them to buyers, is also increasing. This study explores the model that can identify frauds in the online C2C second-hand market by examining the postings for transactions. For this goal, this study collected 145,536 field data from actual C2C second-hand market. Then, the model is built with the characteristics from postings such as the topic and the linguistic characteristics of the product description, and the characteristics of products, postings, sellers, and transactions. The constructed model is then trained by the machine learning algorithm XGBoost. The final analysis results show that fraudulent postings have less information, which is also less specific, fewer nouns and images, a higher ratio of the number and white space, and a shorter length than genuine postings do. Also, while the genuine postings are focused on the product information for nouns, delivery information for verbs, and actions for adjectives, the fraudulent postings did not show those characteristics. This study shows that the various features can be extracted from postings written in C2C second-hand transactions and be used to construct an effective model for frauds. The proposed model can be also considered and applied for the other C2C platforms. Overall, the model proposed in this study can be expected to have positive effects on suppressing and preventing fraudulent behavior in online C2C markets.

Effects of Social Support, Sleep Quality, and Oral Health Impact Profile on Depression among Pregnant Women (일부 임신부의 사회적 지지, 수면의 질 및 구강건강영향지수가 우울수준에 미치는 영향)

  • Han, Se-Young;Han, Yang-Keum
    • Journal of dental hygiene science
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    • v.17 no.2
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    • pp.134-141
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    • 2017
  • This study examined 191 pregnant women before delivery in an obstetrics and gynecology clinic in North Gyeongsang Province from May to September 2016 by using a questionnaire after obtaining informed consent for voluntary participation in the study. The study was performed to investigate the association of depression with sociodemographic characteristics, pregnancy-related characteristics, social support, sleep quality and Oral Health Impact Profile (OHIP) in pregnant women. The prevalence of depression among the pregnant women was 25.1% in the healthy group and 74.9% in the depression group. The depression level was significantly higher in women in the depression group who were unsatisfied with their marriage life, had no occupation, had lower social support, had poor sleep quality and had higher OHIP scores. The results of the logistic regression analysis indicated that, the risk ratio for more severe depression was significantly higher in the group with no experience of miscarriage and induced childbirth than in the group with childbirth experience. Conversely, the risk ratio for more severe depression was significantly lower in the group with high social support than in the group with low social support. Depression in the respondents significantly positively correlated with sleep quality and OHIP score but significantly negatively correlated with social support. The multiple regression analysis revealed that the depression level was significantly higher by 22.3% among pregnant women with lower marital satisfaction, no childbirth experience, lower social support and higher OHIP scores. In summary, depression was related to marital satisfaction, childbirth experience, social support, and OHIP score, among others, in pregnant women in this study. Therefore, further investigation is warranted to construct programs and measures that will help build positive thinking by designing and verifying a three-dimensional study model by taking into consideration various variables to reduce the incidence of depression in pregnant women.