• Title/Summary/Keyword: distribution of elements

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Community Ecological Study on the Quercus acuta Forests in Bogildo-Island (보길도(甫吉島) 붉가시나무림(林)의 군락생태학적(群落生態學的) 연구(硏究))

  • Kim, Chong-Young;Lee, Jeong-Seok;Oh, Kwang-In;Jang, Seok-Ki;Park, Jin-Hong
    • Journal of Korean Society of Forest Science
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    • v.89 no.5
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    • pp.618-629
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    • 2000
  • This study was carried out to investigate ecological niche of Quercus acuta communities in Bogildo-island from July to October, 1998. This island is occupied by a subtropical evergreen broad-leaved forests. The study on community ecology of Q. acuta, mostly dominant species of subtropical forests, is very important for successful forest management. Sampling areas were selected in 16 quadrats, dominated by Q. acuta to examine the vegetation characteristics(plant identification, D.B.H.) and environmental elements (microtopography, altitude, slope degree, aspect, illumination and soil physicochemical properties). On the basis of data from field surveys, importance values were calculated for the dominance of Q. acuta and volume growth was analyzed by tree ring widths. The results obtained were as follows ; 1. The lists of vascular plants in the investigations were identified as 54 families, 91 genera, 113 species, 9 varieties, 1 formae. It appeared that 45 kinds were evergreen, 6 kinds(Camellia japonica, Ligustrum japonicum, Eurya japonica, Smilax china, Trachelospermum asiaticum var. intermedium, Carex lanceolata) were commonly observed in all plots and 5 species(Cinnamomum japonicum, Ardisia japonica, Cymbidium goeringii, Dryopteris bissetiana, Viburnum erosum) were most highly observed in all plots(over 80%). 2. The dominating species per strata were, Quercus acuta, Castanopsis cuspidata sp. Quercus salicina, Pinus thunbergii, Prunus sargentii in tree layer, Camellia Japonica, Ligustrum japonicum, Quercus acuta, Eurya japonica, Castanopsis cuspidata sp. in subtree layer, Camellia japonica, Ligustrum japonicum, Smilax china, Cinnamomum japonicum, Viburnum erosum in shrub layer and Trachelospermum asiaticum var. intermedium, Ardisia japonica, Carex lanceolata, Camellia japonica(seedlings), Quercus acuta(seedlings) in herb layer, all in descending orders. 3. Quercus acuta could be suggested as shade intolerant tree, considering the distribution in southern, western, nothern and eastern slopes in the descending orders. 4. Mean relative illumination in the forest is 0.89 % and it is relatively low in brightness. 5. Sustainment of Quercus acuta community couldn't be confirmed by judging from their reverse J curve in even-aged forest, as shown in D.B.H. distribution analysis. 6. The result of annual ring width analysis(mean ; 2.44 mm) showed three stages, such as a gentle increasing(1~12 year ; 2.04 mm), a relatively steep increasing(13~22 year ; 2.95 mm) and decreasing or stagnating(23 year after ; 2.41 mm).

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A Basic Study on the Establishment of Preservation and Management for Natural Monument(No.374) Pyeongdae-ri Torreya nucifera forest of Jeju (천연기념물 제374호 제주 평대리 비자나무 숲의 보존·관리방향 설정을 위한 기초연구)

  • Lee, Won-Ho;Kim, Dong-Hyun;Kim, Jae-Ung;Oh, Hae-Sung;Choi, Byung-Ki;Lee, Jong-Sung
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.32 no.1
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    • pp.93-106
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    • 2014
  • In this study, Analyze environment of location, investigation into vegetation resources, survey management status and establish to classify the management area for Natural monument No.374 Pyengdae-ri Torreya nucifera forest. The results were as follows: First, Torreya nucifera forest is concerned about influence of development caused by utilization of land changes to agricultural region. Thus, establish to preservation management plan for preservation of prototypical and should be excluded development activity to cause the change of terrain that Gotjawal in the Torreya nucifera forest is factor of base for generating species diversity. Secondly, Torreya nucifera forest summarized as 402 taxa composed 91 familly 263 genus, 353 species, 41 varieties and 8 forms. The distribution of plants for the first grade & second grade appear of endangered plant to Ministry of Environment specify. But, critically endangered in forest by changes in habitat, diseases and illegal overcatching. Therefore, when establishing forest management plan should be considered for put priority on protection. Thirdly, Torreya nucifera representing the upper layer of the vegetation structure. But, old tree oriented management and conservation strategy result in poor age structure. Furthermore, desiccation of forest on artificial management and decline in Torreya nucifera habitat on ecological succession can indicate a problem in forest. Therefore, establish plan such as regulation of population density and sapling tree proliferation for sustainable characteristics of the Torreya nucifera forest. Fourth, Appear to damaged of trails caused by use. Especially, Scoria way occurs a lot of damaged and higher than the share ratio of each section. Therefore, share ratio reduction Plan should be considered through the additional development of tourism routes rather than the replacement of Scoria. Fifth, Representing high preference of the Torreya nucifera forest tourist factor confirmed the plant elements. It is sensitive to usage pressure. And requires continuous monitoring by characteristic of Non-permanent. In addition, need an additional plan such as additional development of tourism elements and active utilizing an element of high preference. Sixth, Strength of protected should be differently accordance with importance. First grade area have to maintenance of plant population and natural habitats. Set the direction of the management. Second grade areas focus on annual regeneration of the forest. Third grade area should be utilized demonstration forest or set to the area for proliferate sapling. Fourth grade areas require the introduced of partial rest system that disturbance are often found in proper vegetation. Fifth grade area appropriate to the service area for promoting tourism by utilizing natural resources in Torreya nucifera forest. Furthermore, installation of a buffer zone in relatively low ratings area and periodic monitoring to the improvement of edge effect that adjacent areas of different class.

Development of a split beam transducer for measuring fish size distribution (어체 크기의 자동 식별을 위한 split beam 음향 변환기의 재발)

  • 이대재;신형일
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.37 no.3
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    • pp.196-213
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    • 2001
  • A split beam ultrasonic transducer operating at a frequency of 70 kHz to use in the fish sizing echo sounder was developed and the acoustic radiation characteristics were experimentally analyzed. The amplitude shading method utilizing the properties of the Chebyshev polynomials was used to obtain side lobe levels below -20 dB and to optimize the relationship between main beam width and side lobe level of the transducer, and the amplitude shading coefficient to each of the elements was achieved by changing the amplitude contribution of elements with 4 weighting transformers embodied in the planar array transducer assembly. The planar array split beam transducer assembly was composed of 36 piezoelectric ceramics (NEPEC N-21, Tokin) of rod type of 10 mm in diameter and 18.7 mm in length of 70 kHz arranged in the rectangular configuration, and the 4 electrical inputs were supplied to the beamformer. A series of impedance measurements were conducted to check the uniformity of the individual quadrants, and also in the configurations of reception and transmission, resonant frequency, and the transmitting and receiving characteristics were measured in the water tank and analyzed, respectively. The results obtained are summarized as follows : 1. Average resonant and antiresonant frequencies of electrical impedance for four quadrants of the split beam transducer in water were 69.8 kHz and 83.0 kHz, respectively. Average electrical impedance for each individual transducer quadrant was 49.2$\Omega$ at resonant frequency and 704.7$\Omega$ at antiresonant frequency. 2. The resonance peak in the transmitting voltage response (TVR) for four quadrants of the split beam transducer was observed all at 70.0 kHz and the value of TVR was all about 165.5 dB re 1 $\mu$Pa/V at 1 m at 70.0 kHz with bandwidth of 10.0 kHz between -3 dB down points. The resonance peak in the receiving sensitivity (SRT) for four combined quadrants (quad LU+LL, quad RU+RL, quad LU+RU, quad LL+RL) of the split beam transducer was observed all at 75.0 kHz and the value of SRT was all about -177.7 dB re 1 V/$\mu$Pa at 75.0 kHz with bandwidth of 10.0 kHz between -3 dB down points. The sum beam transmitting voltage response and receiving senstivity was 175.0 dB re 1$\mu$Pa/V at 1 m at 75.0 kHz with bandwidth of 10.0 kHz, respectively. 3. The sum beam of split beam transducer was approximately circular with a half beam angle of $9.0^\circ$ at -3 dB points all in both axis of the horizontal plane and the vertical plane. The first measured side lobe levels for the sum beam of split beam transducer were -19.7 dB at $22^\circ$ and -19.4 dB at $-26^\circ$ in the horizontal plane, respectively and -20.1 dB at $22^\circ$ and -22.0 dB at $-26^\circ$ in the vertical plane, respectively. 4. The developed split beam transducer was tested to estimate the angular position of the target in the beam through split beam phase measurements, and the beam pattern loss for target strength corrections was measured and analyzed.

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A Study on the Effects of the Dine-out Franchise Headquarter's Management and Support Policies and Franchise Business Operator's Managerial Characteristics on the Bilateral Relationship and Franchise Store's Satisfaction (외식 프랜차이즈 가맹본부의 관리 및 지원정책과 가맹점 사업자의 경영자적 특성이 양자간 관계와 가맹점의 만족에 미치는 영향에 관한 연구)

  • Seo, SangYun;Jang, JaeNam
    • Journal of Distribution Research
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    • v.17 no.4
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    • pp.81-101
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    • 2012
  • A franchise system develops competitive products for a franchise store through the system established by the franchise head office. Therefore, it has advantages of expanding the marketing effect since the risk of failure is reduced for a founder and the franchise head office supports the overall sales, advertisement and promotional activities. Also, a franchise store has advantages of fulfilling necessary facilities and tools on advantageous terms, reducing expenses by purchasing in bulk, and getting a supply of products with stable qualities. However, aside from such advantages, franchise head offices are forcing franchise stores to make unnecessary investments in equipments and remodel the interior. Also, franchise business operators are being made to share the cost of marketing and multiple franchise stores are being approved within the same business district, and franchise business operators are suffering damages. Therefore, cases of shutting down a franchise store or not renewing the contract are frequent. From the position of a franchise head office, profits that are generated from franchise fees, interior remodeling fees and supplying facilities and materials will increase as the number of new franchise stores increases. However, franchise stores are faced with difficulties due to excessive competitions between similar types of businesses and the overlapping of business districts that come from increases in the number of stores, and they eventually end up shutting down. Therefore, in order for a franchise business operator and franchise head office to grow and develop continuously, opening new stores is important, but successfully renewing the contract by maintaining a relationship with an existing franchise business operator is desirable. In this aspect, a study that examines the elements that can affect the relationship between a franchise business operator and franchise head office is believed to be important for the development of the franchise industry and creating safe jobs for the public. With an emphasis on the relationship between a franchise head office and franchise store, this study attempted to examine the effect of characteristics of a franchise head office and franchise business operator on the bilateral relationship such as the faith and immersion, and wished to review the effects of such faith and immersion on the satisfaction of a franchise store, including an intention of renewing the contract. In particular, in the current situation of great uncertainties in the market, this study also wished to examine how uncertain market elements will affect the relationship between the characteristics of a franchise head office and franchise business operator, and the faith and immersion. The study revealed that among the characteristics of a franchise head office, the standardization management of a franchise head office hinders a franchise store's faith and immersion in a franchise head office. Also, a franchise head office's support was shown to increase a franchise store's faith and immersion. However, it was revealed that a franchise head office's regulation and incentive policies for a franchise store do not affect a franchise store's faith and immersion. Among characteristics of a franchise business operator, a franchise store's healthy financial status and entrepreneur spirits were shown to enhance the faith and immersion in a franchise head office. However, it was shown that excellent business abilities of a franchise business operator actually reduce the immersion for a franchise head office. Also, the faith and immersion in a franchise head office were shown to enhance the intention of renewing the contract by increasing the satisfaction for a franchise head office. In addition, it was originally believed that the effects of a franchise business operator's characteristics on the faith and immersion in a franchise head office will vary depending on the market uncertainty, but the effect of a franchise business operator's characteristics depending on the recognition of uncertainties was shown to be insignificant. Such findings show that instead of making a franchise store pay for equipment investments and marketing and obtaining profits by force, a franchise head office should actively support a franchise store so that a franchise store's business activities can be conducted well, which will bring profits to a franchise store and ultimately to a franchise head office. This is a more desirable direction for the development of both parties. Implications of such findings are summarized as follows. First, it was shown that a franchise head office's standardization management actually reduces a franchise store's faith and immersion. Therefore, it is believed that instead of conducting standardization managements for regulating and managing franchise stores, measures should be developed so that franchise stores can actually participate voluntarily. For this, a head office should put in efforts to develop and provide standardized manuals, and make sure that a self-review system takes root. Second, a franchise head office's incentives did not have significant effects on the faith and immersion, but the support was shown to be effective. Therefore, it can be seen that instead of taking post-measures for a franchise store, taking pre-measures of actively supporting is more effective in maintaining a franchise store. Third, among characteristics of a franchise head office, it was shown that a franchise store's healthy financial status increased the faith and immersion in a franchise head office. Therefore, when selecting a franchise business operator, instead of thoughtlessly opening up franchise stores for the profit of a head office, it is believed that reviewing a franchise business operator's financial firepower and credit status is necessary. As for academic implications, previous studies examined the relationship by focusing on the characteristics of a franchise head office and franchise store, but this study focused on the characteristics of a franchise business operator. Therefore, this study dealt with the importance of a franchise business operator's competence, and is significant because it revealed the fact that a franchise business operator's excellent commercialization ability can become an element that hinders the immersion in a franchise head office. It was originally believed that a franchise store's characteristics will have different effects on the faith and immersion depending on the market uncertainty, but it was shown that the effect of a franchise store's characteristics depending on the recognition of uncertainties was insignificant, and that is the limitation of this study.

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The Roles of Service Failure and Recovery Satisfaction in Customer-Firm Relationship Restoration : Focusing on Carry-over effect and Dynamics among Customer Affection, Customer Trust and Loyalty Intention Before and After the Events (서비스실패의 심각성과 복구만족이 고객-기업 관계회복에 미치는 영향 : 실패이전과 복구이후 고객애정, 고객신뢰, 충성의도의 이월효과 및 역학관계 비교를 중심으로)

  • La, Sun-A
    • Journal of Distribution Research
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    • v.17 no.1
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    • pp.1-36
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    • 2012
  • Service failure is one of the major reasons for customer defection. As the business environment gets tougher and more competitive, a single service failure might bring about fatal consequences to a service provider or a firm. Sometimes a failure won't end up with an unsatisfied customer's simple complaining but with a wide-spread animosity against the service provider or the firm, leading to a threat to the firm's survival itself in the society. Therefore, we are in need of comprehensive understandings of complainants' attitudes and behaviors toward service failures and firm's recovery efforts. Even though a failure itself couldn't be fixed completely, marketers should repair the mind and heart of unsatisfied customers, which can be regarded as an successful recovery strategy in the end. As the outcome of recovery efforts exerted by service providers or firms, recovery of the relationship between customer and service provider need to put on the top in the recovery goal list. With these motivations, the study investigates how service failure and recovery makes the changes in dynamics of fundamental elements of customer-firm relationship, such as customer affection, customer trust and loyalty intention by comparing two time points, before the service failure and after the recovery, focusing on the effects of recovery satisfaction and the failure severity. We adopted La & Choi (2012)'s framework for development of the research model that was based on the previous research stream like Yim et al. (2008) and Thomson et al. (2005). The pivotal background theories of the model are mainly from relationship marketing and social relationships of social psychology. For example, Love, Emotional attachment, Intimacy, and Equity theories regarding human relationships were reviewed. As the results, when recovery satisfaction is high, customer affection and customer trust that were established before the service failure are carried over to the future after the recovery. However, when recovery satisfaction is low, customer-firm relationship that had already established in the past are not carried over but broken up. Regardless of the degree of recovery satisfaction, once a failure occurs loyalty intention is not carried over to the future and the impact of customer trust on loyalty intention becomes stronger. Such changes imply that customers become more prudent and more risk-aversive than the time prior to service failure. The impact of severity of failure on customer affection and customer trust matters only when recovery satisfaction is low. When recovery satisfaction is high, customer affection and customer trust become severity-proof. Interestingly, regardless of the degree of recovery satisfaction, failure severity has a significant negative influence on loyalty intention. Loyalty intention is the most fragile target when a service failure occurs no matter how severe the failure criticality is. Consequently, the ultimate goal of service recovery should be the restoration of customer-firm relationship and recovery of customer trust should be the primary objective to accomplish for a successful recovery performance. Especially when failure severity is high, service recovery should be perceived highly satisfied by the complainants because failure severity matters more when recovery satisfaction is low. Marketers can implement recovery strategies to enhance emotional appeals as well as fair treatments since the both impacts of affection and trust on loyalty intention are significant. In the case of high severity of failure, recovery efforts should be exerted to overreach customer expectation, designed to directly repair customer trust and elaborately designed in the focus of customer-firm communications during the interactional recovery process to affect customer trust rebuilding indirectly. Because it is a longer and harder way to rebuild customer-firm relationship for high severity cases, low recovery satisfaction cannot guarantee customer retention. To prevent customer defection due to service failure of high severity, unexpected rewards as a recovery will be likely to be useful since those will lead to customer delight or customer gratitude toward the service firm. Based on the results of analyses, theoretical and managerial implications are presented. Limitations and future research ideas are also discussed.

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The Development of Vulnerable Elements and Assessment of Vulnerability of Maeul-soop Ecosystem in Korea (한국 마을숲 생태계 취약요소 발굴 및 취약성 평가)

  • Lim, Jeong-Cheol;Ryu, Tae-Bok;Ahn, Kyeong-Hwan;Choi, Byoung-Ki
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.34 no.4
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    • pp.57-65
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    • 2016
  • Maeul-soop(Village forest) is a key element of Korean traditional village landscape historically and culturally. However, a number of Maeul-soops have been lost or declined due to various influences since the modern age. For this Maeul-soop that has a variety of conservation values including historical, cultural and ecological ones, attention and efforts for a systematic conservation and restoration of Maeul-soop are needed. The purpose of the present study is to provide information on ecological restoration and sustainable use and management of Maeul-soops based on component plant species, habitat and location characteristics of 499 Maeul-soops spread throughout Korea. Major six categories of threat factors to Maeul-soop ecosystem were identified and the influence of each factor was evaluated. For the evaluation of weight by threat factors for the influence on the vulnerability of Maeul-soop ecosystem, more three-dimensional analysis was conducted using Analytic Hierarchy Process (AHP) analysis method. In the results of evaluation using AHP analysis method, reduction of area, among six categories, was spotted as the biggest threat to existence of Maeul-soops. Next, changes in topography and soil environment were considered as a threat factor of qualitative changes in Maeul-soop ecosystem. Influence of vegetation structure and its qualitative changes on the loss or decline of Masul-soop was evaluated to be lower than that of changes in habitat. Based on weight of each factor, the figures were converted with 100 points being the highest score and the evaluation of vulnerability of Maeul-soop was conducted with the converted figures. In the result of evaluation of vulnerability of Maeul-soops, grade III showed the highest frequency and a normal distribution was formed from low grade to high grade. 38 Maeul-soops were evaluated as grade I which showed high naturality and 10 Maeul-soops were evaluated as grade V as their maintenance was threatened. Also in the results of evaluation of vulnerability of each Maeul-soop, restoration of Maeul-soop's own area was found as top priority to guarantee the sustainability of Maeul-soops. It was confirmed that there was a need to prepare a national level ecological response strategy for each vulnerability factor of Maeul-soop, which was important national ecological resources.

Study on Vegetation Analysis for Indicators Development of Agro-ecosystem Habitat Quality (농업생태계의 서식지 질 지표 개발을 위한 식생분석)

  • Park, Kwang-Lai;Kang, Bang-Hun;Choi, Jae-Woong;Kim, Chang-Hwan
    • Korean Journal of Soil Science and Fertilizer
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    • v.43 no.6
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    • pp.1040-1046
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    • 2010
  • This research is composed of a series of survey of existing plants species by classifying biotope type of agro-ecosystem of Guksoo village area of Yangpyeong County, to collect and analyze basic data of vegetation analysis for indicators development of agro-ecosystem habitat quality. From the observation area, we found total 141 kinds of tracheophytes (53 Family 114 Genus 124 Species 16 Variety 1 Breed) and they are 3.36% of total Korean tracheophytes (4,191 kinds). Among those 141 tracheophytes, there are 23 kinds of naturalized plants (11 Family 20 Genus 20 Species 2 Variety) and they are 8.61% of total Korean naturalized plants (267 kinds). Among those 141 tracheophytes, they include 0.71% of pteridophyte, 0.71% of gymnosperm, 98.58% of angiosperm. So, most of them are angiosperm. When we classify them according to plant life form characteristics, dormant/diapause type plants include 45 species (31.91%) of annual plant (Th), 19 species (13.48%) of Th (w), 17species (12.06%) of hemicryptophyte (H). Regarding propagation type, as for the Radicoid form, there are 99 species (70.21%) of crumb structure plant, 13 species (9.22%) of $R_4$, 12 species (8.51%) of $R_{2.3}$ are the crumb structure does not make any connection on the ground or under ground. As for the Disseminule form of propagation type, there are 62 species (43.97%) of Gravity dispersal type $D_4$), 23 species (16.31%) of Wind dispersal type ($D_1$), 21 species (14.89%) of $D_{1.4}$. According to this survey of plant distribution rate by plant life form characteristics, we may acquire many knowledge about species composition of sociability, cluster's reaction against environmental elements, space usage and possible species competition in community. It may be very useful basic data for habitat preservation to keep and promote biological diversity.

Survey of the Status of Conutry-of-origin Lables and Hygine on the Meat Markets of 4 Regions in Korea (4개 권역 축산물 판매업소의 원산지 표시실태 및 위생상태 표본조사)

  • Nam, Bo-Ra;Nam, Jung-Oak;Park, Jung-Min;Lee, Ra-Mi;Gu, Hyo-Jung;Kim, Myung-Hee;Chang, Un-Jae;Suh, Hyung-Joo;Kim, Jin-Man
    • Food Science of Animal Resources
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    • v.27 no.1
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    • pp.122-126
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    • 2007
  • Expenditure on meat and meat products has been increased in Korea due to the increase of income and the change of diet. From raising farm animals to eating the meat, various hazardous elements can make their ways into the meat and meat products. Recently the issues on food safety and hygiene are drawing a lot of attention, and the current system for managing the safety of foods is still needed to be improved. This survey was aimed to monitor the current situation of country-of-origin labels and hygiene for the meat markets at 4 regions Korea. The survey was performed by collecting samples from whole- sale and retail stores in the nation, which were selling beef. The markets were divided into groups as to territory and the size of the market (Large size, Medium size, and Small size). In terms of size distribution, small butcher shops occupied the highest percentage. On the itemized suitability test of unpacked and packed beef, all the market of 4 regions showed good agreements. However, such labels indicating the methods of cooking and storage were not properly posted on the products. Especially for Ho-nam region, corrections are needed. The results of monitoring sanitation conditions for the butcher shops at 4 regions in Korea showed relatively low suitability. Especially, there were serious lack of knowledge about wearing the sanitation clothing, caps, and shoes. The problem with food safety is so complicated that producer, consumer, food manufacturer, the press, the government, and scholar should solve altogether. It is necessary to educate farmers, food handlers, consumers, etc. and provide them with an accurate information and knowledge.

Mineralogy and Genesis of Hydrothermal Deposits in the Southeastern Part of Korean Peninsula : (5) Deogbong Napseok Deposit (우리나라 동남부 지역의 열수광상에 대한 광물학적 및 광상학적 연구:(5) 덕봉납석광상)

  • Kim, Soo-Jin;Choo, Chang-Oh;Kim, Won-Sa
    • Journal of the Mineralogical Society of Korea
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    • v.7 no.1
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    • pp.25-39
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    • 1994
  • The Deogbong napseok clay deposit which is composed mainly of dickite and pyrophyllite has been formed by hydrothermal alteration of the Late Cretaceous volcanic rocks consisting of andesitic tuff and andesite. The mineralogy of the napseok ores and the hydrothermal alteration processes have been studied in order to know the nature of the interaction between minerals and fluids for the formation of the deposit. Chemical distribution shows that alkali elements and silica were mobile but alumina was relatively immobile during the hydrothermal processes. It is evident that enrichment of alumina and leaching of silica from the host rock led to the formation of the napseok ore, whereas the enrichment of silica in the outer zone of the deposit gave rise to the silica zone. A large amount of microcrystalline quartz closely associated with dickite and pyrophyllite suggests the increasing activity of silica. Thus Si which was released away from the argillic zone by the increasing activity of silica. Thus Si which was released away from the argillic zone by the increasing activity of silica solubility moved out precipitating in the margin of the deposit to form the silica zone. Variation in dickite crystallinity implies the local change in the stability of the system. Thermodynamic calculation shows that the invariant point of pyrophyllite-dickite (kaolinite)-diaspore-quartz assemblages at 500 bars in the system $Al_{2}O_{3}-SiO_{2}-H_{2}O$ is about 300 $^{\circ}C$. Based on the mineral assemblages and the experimental data reported, it is estimated that the main episode of hydrothermal alteration occurred at least above 270 to 300 $^{\circ}C$ and $X_{CO_2}$ <0.025. Mineral occurrence and chemical variation indicate that the activity of Al is high in the upper part of the deposit, whereas the activity of Si is high in the lower part and the margin of the deposit. The nonequilibrium phase relations observed in the Deogbong deposit might be due to local change in intensive thermodynamic variables and fluid transport properties that resulted in the formation of nonequilibrium phases b of several stages.

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A Study on the Concentration of Nanoparticles and Heavy Metals in Indoor/Outdoor Air in a University Administrative Public Office (대학교 행정실 실내 외 공기 중 나노입자와 중금속 농도에 관한 연구)

  • Choi, Su-Hyeon;Im, Ji-Young;Park, Hee-Jin;Chung, Eun-Kyung;Kim, Jong-Oh;Son, Bu-Soon
    • Journal of Environmental Health Sciences
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    • v.38 no.6
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    • pp.493-502
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    • 2012
  • Objectives: The purpose of this study is to investigate the mass concentration of nanoparticles and understand the characteristics of elements of heavy metal concentrations within nanoparticles in the air using Micro-Orifice Uniform Deposit Impactor Model-110 (MOUDI-110), based on indoor and outdoor air. Methods: This Study sampled nanoparticles using MOUDI-110 indoors (office) and outdoors at S University in Asan, Korea in order to reveal the concentration of nanoparticles in the air. Sampling continued for nine months (10 times indoors and 14 times outdoors) from March to November 2010. Mass concentrations of nanoparticle and concentrations of heavy metals (Al, Mn, Zn, Ni, Cu, Cr, Pb) were analyzed. Results: Indoors, geometric mean concentration of nanoparticles ranged in size from 0.056 ${\mu}m$ to 0.10 ${\mu}m$ and those of 0.056 ${\mu}m$ or less recorded 0.929 ${\mu}g/m^3$ and 1.002 ${\mu}g/m^3$, respectively. On the other hand, the levels were lower outdoors with 0.819 ${\mu}g/m^3$ and 0.597 ${\mu}g/m^3$. Mann-Whitney U tests showed that the difference between the indoors and the outdoors was statistically meaningful in terms of particles of 0.056 ${\mu}m$ or less (p<0.05) in size. These results are possibly influenced by the use of printers and duplicators as the factor that increased the concentration of nanoparticles. In seasonal concentration distribution, the level was higher during the summer compared to in the autumn. Those of 0.056 ${\mu}m$ or less in size presented a statistically meaningful difference during the summer (p<0.05). These results may be influenced by photochemical event as the factor that makes the levels high. Regarding zinc, among the other heavy metals, the fine particles ranged in size from 0.056 ${\mu}m$ to 0.10 ${\mu}m$ and those of 0.056 ${\mu}m$ or less recorded 1.699 $ng/m^3$ and 1.189 $ng/m^3$ in the outdoors. In the indoors, the levels were lower, with 0.745 $ng/m^3$ and 0.617 $ng/m^3$. Cr and Ni at the size of 0.056 ${\mu}m$ or less, both of which have been known to pose severe health effects, recorded higher concentrations indoors with 0.736 $ng/m^3$ and 0.177 $ng/m^3$, compared to 0.444 $ng/m^3$ and 0.091 $ng/m^3$ outdoors. By season, Zn, Ni, Cu and Pb posted a high level of indoor concentration during the fall. As for Cr, the level of concentration indoors was higher than outdoors both during the summer and the autumn. Conclusion: This study indicates the result of an examination of nano-sized particles and heavy metal concentrations. It will provide useful data for the determination of basic nanoparticle standards in the future.