• Title/Summary/Keyword: System-Engineering Process

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The Physiologic change associated with aging, essential nutrients and their diseases in senior or geriatric dogs (노령견의 생리적 변화에 따른 필요 영양소 및 질병에 관한 연구)

  • Jung, Hyung-hak
    • Journal of the Korean Applied Science and Technology
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    • v.35 no.4
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    • pp.1456-1471
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    • 2018
  • This article discusses the nutritional requirements, reviews senior or geriatric dog nutritional evaluation, and then addresses some common nutrition-related problems in older dogs. The purpose of this study was to investigate the Physiologic change associated with aging, essential nutrients and their diseases in senior or geriatric dog subjects. According to a 2002 market research, 30% to 40% of dogs raisedin the United States are 7 years of age. In Europe the number of dogs considered to be "senior or geriatric" (>7 years of age) increased by approximately 50% between 1983 and 1995. A 2012 e-mail survey of 50,347 respondents revealed that 33.2% of dogs were 6 to 10 years of age and 14.7% were older than 11 years in the United States. The average life expectancy of dogs raised in the home is affected by health care, aging and nutrition.And, the aging process is influenced by breed size, genetics, nutrition, environment, and other factors. Although many pets remain active and youthful well into their teens, most dogs start to slow down and may show signs of aging beginning as early as 5 or 6 years of age. Improvements in the control of various diseases and in the nutrition of dogs have resulted in a gradual increase in the average lifespan of companion dogs. Nutritional goals for aging dogs include supporting health and vitality, preventing the onset or slowing the progression of age-related health disorders, and enhancing the dog's quality of life and, if possible, life expectancy. Aging brings with its physiologicchanges. Some changes are obvious, such as whitening of hair, a general decline in body and coat condition, and failing senses including sight and hearing. Other changes are less obvious, however, and these include alterations in the physiology of the digestive tract, immune system, kidneys, and other organs. Nutritional requirements can change with age. In addition, many diseases common in older dogs may be nutrient-sensitive, meaning that diet can play an important role in the management of the condition.

Current status and prospects of approval of the new technology-based food additives (신기술이용 식품첨가물 국내·외 심사 현황 및 전망)

  • Rhee, Jin-Kyu
    • Food Science and Industry
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    • v.52 no.2
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    • pp.188-201
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    • 2019
  • In the past, food additives were classified and managed as chemical synthetic and natural additives according to the manufacturing process, but it was difficult to confirm the purpose or function of food additives.CODEX, an internationalstandard, classifies food additives according to their practical use, based on scientific evidence on the technical effects of food additives, instead of classifying them as synthetic or natural. Therefore, very recently, the food additive standards in Korea have been completely revised in accordance with these global trends. Currently, the classification system of food additives is divided into 31 uses to specify their functions and purposes instead of manufacturing methods. Newer revision of the legislative framework for defining and expanding the scope of the Act as an enlarged area is required. Competition for preempting new food products based on bio-based technology is very fierce in order to enhance the safety of domestic people and maximize the economic profit of their own countries. In this age of infinite competition, it is very urgent to revise or supplement the current regulations in order to revitalize the domestic food industry and enhance national competitiveness through the development of food additives using new biotechnology. In this report, current laws on domestic food ingredients, food additives and manufacturing methods, and a comparison of domestic and foreign advanced countries' regulations and countermeasures strategies were reviewed to improve national competitiveness of domestic advanced biotechnology-based food additives industry.

A Study on the Establishment of Preservation Area for the Preservation of Historical and Cultural Space in the Ancient Village - Focused on the Hongcun, China - (고촌락 역사문화공간 보존을 위한 보호구역 설정 방안 연구 - 중국 굉촌을 중심으로 -)

  • Shin, Hyun-Sil;Dai, Gai-Rong
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.40 no.1
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    • pp.65-73
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    • 2022
  • This paper analyzed the characteristics of ancient villages in Hongcun and the method of resetting the preservation area for the preservation of the changed historical and cultural space in Hongcun through the process of change. To this end, the current status of preservation areas and utilization areas in the village was identified through ancient documents, old paintings, policy materials, and interviews related to the village, and through this, the problem of resetting the preservation area was examined. As a result, the following conclusions were drawn. First, Hongcun is a village built under the influence of Confucianism, Buddhism, and Taoism, and the spatial organization was created according to the hierarchy of Confucianism. As a result, it was possible to inherit and preserve the heritage of ancestors even though the central government did not preserve it. Second, the concept of preservation in a limited sense has been applied as Hongcun has been recognized as a cultural heritage that has been passed down since ancient times, but the Great Leap Forward and the Cultural Revolution brought about changes in the village space. Since then, ancient buildings, water systems, and forests have been preserved through regulations on new construction and expansion of a building with the Hongchon preservation plan, but the development within the preservation area is underway due to changes in the lives of original inhabitants, which were followed by continued development pressure and reform and opening. Third, the original inhabitant of ancient villages had a high perception of the value of the heritage, but they demanded the preparation of measures to improve living conditions and create profits, and the active use of villages for this. Fourth, the forest consisting of old trees is being restored, but the gardens in the old house are showing a phenomenon that the garden space is reduced or transformed for use. The bridges and parking lots were newly built in the southern area, which was extended from the western area, the original entrance to the ancient village, resulting in changes in the existing entrance. This was found to be the primary cause of the spatial change of the ancient village, as the road system was modified to make it convenient for tourists to enter and exit. Fifth, the existing preservation area should be reset and preserved by resetting the preservation route centered on Wolso(half Moon Pool), while the surrounding area should be set as a direct and indirect experience space, and according to the hierarchy of each space, the utilization should proceed while the preservation is carried out by crossing the preservation and the utilization.

Applying the Theory of Affordance to the Design of Water Purification Facilities : Focusing on the Case of Binh Dinh in Vietnam (정수시설 설계에 대한 어포던스 이론 적용 연구: 베트남 빈딘 사례를 중심으로)

  • Park, Hye-Rin;Hwang, Yeo-Kyeong;Kim, Seul-Gi;Lee, Jun-Min;Hwang, Jun-Seok
    • Journal of Appropriate Technology
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    • v.6 no.1
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    • pp.28-36
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    • 2020
  • Sustainable appropriate technology requires user-centered design with consideration of the political, cultural and environmental aspects of the area. However, in the preparation of appropriate technology, there is a limit to the prior grasp of the user's intention and experience leading to the actual behavior of the user after the dissemination. As a result, appropriate technologies are often inconvenient for practical use or used for other purposes, contrary to the designer's intention. This study analyzes the case of appropriate technology with an analysis framework that reflects Maier's affordance theory, and proposes a design solution that can overcome the limitations of existing design. Affordance theory is the theory of factors that cause the user to identify and use features through interpretation based on prior knowledge and experience about things. The analysis cases in this study are the interviews with the designers, management education materials, and manager interviews for water purification systems at three of six schools in Binh Dinh Province, Vietnam, from August 2015 to January 2018. The case was attempted to be improved by periodic installation, maintenance, and inspection, but similar problems continued to occur. First, the facility inspections and manager interviews are compared with manager training materials distributed at the time of installation to find inconsistencies. Next, we analyze the designer's intended affordance and the affordances that actually influenced the management behavior. And then, we propose design solutions based on commonly found problems and affordances. This study suggests that it is necessary to apply the design considering the user's behavior before distributing the appropriate technology, and this study will be precedent in the process of finding the improvement through the analysis framework based on the affordance.

Ammonia Decomposition over Ni Catalysts Supported on Zeolites for Clean Hydrogen Production (청정수소 생산을 위한 암모니아 분해 반응에서 Ni/Zeolite 촉매의 반응활성에 관한 연구)

  • Jiyu Kim;Kyoung Deok Kim;Unho Jung;Yongha Park;Ki Bong Lee;Kee Young Koo
    • Journal of the Korean Institute of Gas
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    • v.27 no.3
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    • pp.19-26
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    • 2023
  • Hydrogen, a clean energy source free of COx emissions, is poised to replace fossil fuels, with its usage on the rise. Despite its high energy content per unit mass, hydrogen faces limitations in storage and transportation due to its low storage density and challenges in long-term storage. In contrast, ammonia offers a high storage capacity per unit volume and is relatively easy to liquefy, making it an attractive option for storing and transporting large volumes of hydrogen. While NH3 decomposition is an endothermic reaction, achieving excellent low-temperature catalytic activity is essential for process efficiency and cost-effectiveness. The study examined the effects of different zeolite types (5A, NaY, ZSM5) on NH3 decomposition activity, considering differences in pore structure, cations, and Si/Al-ratio. Notably, the 5A zeolite facilitated the high dispersion of Ni across the surface, inside pores, and within the structure. Its low Si/Al ratio contributed to abundant acidity, enhancing ammonia adsorption. Additionally, the presence of Na and Ca cations in the support created medium basic sites that improved N2 desorption rates. As a result, among the prepared catalysts, the 15 wt%Ni/5A catalyst exhibited the highest NH3 conversion and a high H2 formation rate of 23.5 mmol/gcat·min (30,000 mL/gcat·h, 600 ℃). This performance was attributed to the strong metal-support interaction and the enhancement of N2 desorption rates through the presence of medium basic sites.

An Empirical Study on Statistical Optimization Model for the Portfolio Construction of Sponsored Search Advertising(SSA) (키워드검색광고 포트폴리오 구성을 위한 통계적 최적화 모델에 대한 실증분석)

  • Yang, Hognkyu;Hong, Juneseok;Kim, Wooju
    • Journal of Intelligence and Information Systems
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    • v.25 no.2
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    • pp.167-194
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    • 2019
  • This research starts from the four basic concepts of incentive incompatibility, limited information, myopia and decision variable which are confronted when making decisions in keyword bidding. In order to make these concept concrete, four framework approaches are designed as follows; Strategic approach for the incentive incompatibility, Statistical approach for the limited information, Alternative optimization for myopia, and New model approach for decision variable. The purpose of this research is to propose the statistical optimization model in constructing the portfolio of Sponsored Search Advertising (SSA) in the Sponsor's perspective through empirical tests which can be used in portfolio decision making. Previous research up to date formulates the CTR estimation model using CPC, Rank, Impression, CVR, etc., individually or collectively as the independent variables. However, many of the variables are not controllable in keyword bidding. Only CPC and Rank can be used as decision variables in the bidding system. Classical SSA model is designed on the basic assumption that the CPC is the decision variable and CTR is the response variable. However, this classical model has so many huddles in the estimation of CTR. The main problem is the uncertainty between CPC and Rank. In keyword bid, CPC is continuously fluctuating even at the same Rank. This uncertainty usually raises questions about the credibility of CTR, along with the practical management problems. Sponsors make decisions in keyword bids under the limited information, and the strategic portfolio approach based on statistical models is necessary. In order to solve the problem in Classical SSA model, the New SSA model frame is designed on the basic assumption that Rank is the decision variable. Rank is proposed as the best decision variable in predicting the CTR in many papers. Further, most of the search engine platforms provide the options and algorithms to make it possible to bid with Rank. Sponsors can participate in the keyword bidding with Rank. Therefore, this paper tries to test the validity of this new SSA model and the applicability to construct the optimal portfolio in keyword bidding. Research process is as follows; In order to perform the optimization analysis in constructing the keyword portfolio under the New SSA model, this study proposes the criteria for categorizing the keywords, selects the representing keywords for each category, shows the non-linearity relationship, screens the scenarios for CTR and CPC estimation, selects the best fit model through Goodness-of-Fit (GOF) test, formulates the optimization models, confirms the Spillover effects, and suggests the modified optimization model reflecting Spillover and some strategic recommendations. Tests of Optimization models using these CTR/CPC estimation models are empirically performed with the objective functions of (1) maximizing CTR (CTR optimization model) and of (2) maximizing expected profit reflecting CVR (namely, CVR optimization model). Both of the CTR and CVR optimization test result show that the suggested SSA model confirms the significant improvements and this model is valid in constructing the keyword portfolio using the CTR/CPC estimation models suggested in this study. However, one critical problem is found in the CVR optimization model. Important keywords are excluded from the keyword portfolio due to the myopia of the immediate low profit at present. In order to solve this problem, Markov Chain analysis is carried out and the concept of Core Transit Keyword (CTK) and Expected Opportunity Profit (EOP) are introduced. The Revised CVR Optimization model is proposed and is tested and shows validity in constructing the portfolio. Strategic guidelines and insights are as follows; Brand keywords are usually dominant in almost every aspects of CTR, CVR, the expected profit, etc. Now, it is found that the Generic keywords are the CTK and have the spillover potentials which might increase consumers awareness and lead them to Brand keyword. That's why the Generic keyword should be focused in the keyword bidding. The contribution of the thesis is to propose the novel SSA model based on Rank as decision variable, to propose to manage the keyword portfolio by categories according to the characteristics of keywords, to propose the statistical modelling and managing based on the Rank in constructing the keyword portfolio, and to perform empirical tests and propose a new strategic guidelines to focus on the CTK and to propose the modified CVR optimization objective function reflecting the spillover effect in stead of the previous expected profit models.

A Study on Estimating Shear Strength of Continuum Rock Slope (연속체 암반비탈면의 강도정수 산정 연구)

  • Kim, Hyung-Min;Lee, Su-gon;Lee, Byok-Kyu;Woo, Jae-Gyung;Hur, Ik;Lee, Jun-Ki
    • Journal of the Korean Geotechnical Society
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    • v.35 no.5
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    • pp.5-19
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    • 2019
  • Considering the natural phenomenon in which steep slopes ($65^{\circ}{\sim}85^{\circ}$) consisting of rock mass remain stable for decades, slopes steeper than 1:0.5 (the standard of slope angle for blast rock) may be applied in geotechnical conditions which are similar to those above at the design and initial construction stages. In the process of analysing the stability of a good to fair continuum rock slope that can be designed as a steep slope, a general method of estimating rock mass strength properties from design practice perspective was required. Practical and genealized engineering methods of determining the properties of a rock mass are important for a good continuum rock slope that can be designed as a steep slope. The Genealized Hoek-Brown (H-B) failure criterion and GSI (Geological Strength Index), which were revised and supplemented by Hoek et al. (2002), were assessed as rock mass characterization systems fully taking into account the effects of discontinuities, and were widely utilized as a method for calculating equivalent Mohr-Coulomb shear strength (balancing the areas) according to stress changes. The concept of calculating equivalent M-C shear strength according to the change of confining stress range was proposed, and on a slope, the equivalent shear strength changes sensitively with changes in the maximum confining stress (${{\sigma}^{\prime}}_{3max}$ or normal stress), making it difficult to use it in practical design. In this study, the method of estimating the strength properties (an iso-angle division method) that can be applied universally within the maximum confining stress range for a good to fair continuum rock mass slope is proposed by applying the H-B failure criterion. In order to assess the validity and applicability of the proposed method of estimating the shear strength (A), the rock slope, which is a study object, was selected as the type of rock (igneous, metamorphic, sedimentary) on the steep slope near the existing working design site. It is compared and analyzed with the equivalent M-C shear strength (balancing the areas) proposed by Hoek. The equivalent M-C shear strength of the balancing the areas method and iso-angle division method was estimated using the RocLab program (geotechnical properties calculation software based on the H-B failure criterion (2002)) by using the basic data of the laboratory rock triaxial compression test at the existing working design site and the face mapping of discontinuities on the rock slope of study area. The calculated equivalent M-C shear strength of the balancing the areas method was interlinked to show very large or small cohesion and internal friction angles (generally, greater than $45^{\circ}$). The equivalent M-C shear strength of the iso-angle division is in-between the equivalent M-C shear properties of the balancing the areas, and the internal friction angles show a range of $30^{\circ}$ to $42^{\circ}$. We compared and analyzed the shear strength (A) of the iso-angle division method at the study area with the shear strength (B) of the existing working design site with similar or the same grade RMR each other. The application of the proposed iso-angle division method was indirectly evaluated through the results of the stability analysis (limit equilibrium analysis and finite element analysis) applied with these the strength properties. The difference between A and B of the shear strength is about 10%. LEM results (in wet condition) showed that Fs (A) = 14.08~58.22 (average 32.9) and Fs (B) = 18.39~60.04 (average 32.2), which were similar in accordance with the same rock types. As a result of FEM, displacement (A) = 0.13~0.65 mm (average 0.27 mm) and displacement (B) = 0.14~1.07 mm (average 0.37 mm). Using the GSI and Hoek-Brown failure criterion, the significant result could be identified in the application evaluation. Therefore, the strength properties of rock mass estimated by the iso-angle division method could be applied with practical shear strength.