• The Journal of Engineering Geology
• /
• v.33 no.4
• /
• pp.587-598
• /
• 2023

To assess the distribution and temporal changes in radon concentration within a region in Yeonpung-myeon, Goesan-gun, known for elevated groundwater radon levels, we conducted a series of analyses, measuring radon concentration and DTW (Depth to water table) at 2-month intervals over 12 cycles. The investigation covered 10 groundwater wells and one stream within the designated area. The groundwater in the central part of the region exhibited high radon concentrations, ranging from 37.0 to 2,675.2 Bq/L. Conversely, the peripheral zones displayed comparatively lower radon concentrations, ranging from 10.6 to 37.9 Bq/L. This variation is attributed to the presence of granite porphyry that intruded into the Okcheon Formation, forming a fracture zone and contributing to elevated radon levels in the central part. In contrast, the peripheral locations, located within the Okcheon Formation and away from the granite porphyry intrusion, demonstrated lower radon concentrations. The observed significant fluctuation in radon concentration in the central area is associated with its low-lying topography. The pronounced seasonal changes in groundwater levels contribute to the migration of shallow, low-radon groundwater into areas with higher radon concentrations, explaining the observed variations in radon levels within the central part of the studied area.

• Proceedings of the Plant Resources Society of Korea Conference
• /
• 2021.04a
• /
• pp.31-31
• /
• 2021

본 연구는 서부 DMZ 및 접경지역에 속하고 인천광역시 강화군 강화읍에 위치한 퇴모·혈구산(466m) 을 대상으로 수행되었다. 강화군은 우리나라에서 4번째로 넓은 면적의 섬으로 알려져있고, 인천광역시 서북부 경기만의 한강 하구에 위치하고 있으며, 서쪽으로는 석모도 등 부속섬과 서해안, 북쪽으로는 북 한의 황해도 연백시, 동쪽으로는 김포시와 강화대교와 강화초지대교가 육지로 연결되어 있다. 2019년 4 월부터 2020년 10월까지 7회에 걸쳐 계절별로 식물상 조사를 진행하였다. 본 연구에서 확인된 해명산 일대에 분포하는 관속식물의 현황은 92과 257속 353속 4아종 41변종 4품종 총 402분류군으로 확인되었다. 양치식물은 6과 9속 10종 2변종 12분류군, 나자식물은 3과 4속 8종 총 8분류군, 쌍자엽식물은 74과 198속 268종 4아종 30변종 3품종 등 305분류군, 단자엽식물은 9과 46속 67종 9변종 1품종 등 77분류군으로 조사되었다. 또한, 식물구계학적 특정식물 IV급은 등 1분류군, III급은 물박달나무, 병아리꽃나무 등 6분 류군, II급은 갯장구채, 꼬리조팝나무 등 8분류군, I급은 야산고비, 일엽초 등 20분류군으로 파악되었 다. 희귀식물은 산림청 지정 희귀식물 취약종(VU)에 속하는 산들깨와 약관심종(LC)에 속하는 쥐방울덩굴 등 총 2분류군이 확인되었다. 특산식물은 백운산원추리 및 병꽃나무 등 4분류이 파악되었다. 침입외래식물은 애기수영 및 유럽점나무도물 등 39분류군으로 확인되었고, 생태계교란식은 가시박 등 4분류군으로 파악되었다. 주변의 신산저수지 및 고비고개에 큰 공사가 진행되고있어 침입외래식물의 개체수는 크게 증가할 것으로 예측었다. 따라서 장기적인 생태계 보전대책 수립이 필요하다고 판단된다.

• Journal of Internet Computing and Services
• /
• v.5 no.1
• /
• pp.25-32
• /
• 2004

Mobile computing environment makes it possible for computing activities to be maintained during movement even if a user changes its network point of attachment. Mobile IP is a standard protocol designed to be used in such mobile computing environment. However, Mobile IP has a drawback to incur a lot of handoff delays and waste network resources, since CoA(Care of Address) registration packets need to go through a HA(Home Agent) first whenever a mobile node moves. To solve this long-standing problem, this paper proposes a new scheme that, for infra-domain movement, efficiently performs local handoff without notifying the HA Specifically, based on the notion of load balance, the proposed scheme allows every FA(Foreign Agent) in a domain to become the root FA(also known as domain FA) dynamically, thus distributing the registration task into many other foreign agents. The dynamic root assignment through load balancing ultimately leads to fast network response due to less frequent transmission of registration packets.

• Journal of KIISE:Databases
• /
• v.29 no.5
• /
• pp.335-346
• /
• 2002

LBS(Location Based Services) provide the location-based information to its mobile users. The primary functionality of these services is to provide useful information to its users at a minimum cost of resources. The functionality can be implemented through data mining techniques. However, conventional data mining researches have not been considered spatial and temporal aspects of data simultaneously. Therefore, these techniques are inappropriate to apply on the objects of LBS, which change spatial attributes over time. In this paper, we propose a new data mining technique for identifying the temporal patterns from the series of the locations of moving objects that have both temporal and spatial dimension. We use a spatial operation of contains to generalize the location of moving point and apply time constraints between the locations of a moving object to make a valid moving sequence. Finally, the spatio-temporal technique proposed in this paper is very practical approach in not only providing more useful knowledge to LBS, but also improving the quality of the services.

• Journal of KIISE:Computer Systems and Theory
• /
• v.36 no.6
• /
• pp.488-501
• /
• 2009

In ubiquitous environments, invisible devices and software are connected to one another to provide convenient services to users. In order to provide such services, we must have mobile devices that connect users and services. But such services are usually limited to those served on a single mobile device. To resolve the resource limitation problem of mobile devices, a nearby resource sharing research has been studied. Also, not only the nearby resource share but also a resource recommendation through context-based resource reasoning has been studied such as an UMO Project. The UMO Project share and manage the various context information for the personalization resource recommendation and reason based on current context information. Also, should verify resource inference rules for reliable the resource recommendation. But, to create various context information requires huge cost and time in actuality. Thus, we propose a inference verification tool called USim to resolve problem. The proposed inference verification tool provides convenient graphic user interfaces and it easily creates context information. The USim exactly verifies new inference rules through dynamic changes of context information.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.29 no.7A
• /
• pp.766-774
• /
• 2004

The future mobile communication system can support not only voice but also multimedia applications such as data, image and video. It requires greater resources than the voice-oriented mobile system. Efficient resource reservation and hand-over schemes are necessary to maintain the same QoS of transmitted multimedia traffic because the QoS may be defected by some delay and information loss during hand-over. This paper proposes a resource reservation scheme to accommodate multimedia traffics in mobile multimedia networks. In our scheme the position of mobile is estimated in two steps, that is, sector estimation and zone estimation. With this position information, the moving direction is determined. According to simulation results, our scheme provides a better performance than conventional methods.

• Annual Conference of KIPS
• /
• 2002.11a
• /
• pp.205-208
• /
• 2002

본 논문에서는 기존의 그리드 컴퓨팅을 위한 미들웨어인 Globus의 정보 서비스 시스템인 MDS의 확장된 정보시스템 설계를 기술한다. 제안된 시스템은 자원 접근 및 발견을 위해 P2P 기반의 결함 포용을 갖는 강건하고 적응형 정보 서비스를 제공한다. MDS 는 가상 조직(Virtual Organization, VO) 으로 이루어진 네트워크 상에 자원의 위치 및 상태 정보를 제공하는 디렉토리 서비스이다. 그러나 현재 MDS 시스템은 결함의 기점(Single-point failure) 및 중복으로 등록된 자원에 대한 추가적인 트래픽을 발생시킨다. P2P 기반 정보 서비스 시스템은 기존의 클라이언트/서버 기반의 정보 서비스에 비해 정보의 가용성이 높고 수동적인 정보 서비스 수행 객체인 VO의 자치성을 보장함으로써 그리드 컴퓨팅 자원에 대한 유효한 실시간 접근을 제공한다. 또한 그리드 컴퓨팅의 확장으로 그리드 컴퓨팅에 참여하는 자원의 수가 증가함에 따라 정보 서비스 시스템의 확장성 및 정보 서비스의 개체인 VO간의 자기 조직화(self-organization)를 지원한다.

• Korean Journal of Plant Resources
• /
• v.18 no.3
• /
• pp.390-402
• /
• 2005

This study was carried out systematically to grasp the resource plants in construct-reserved site of ecological forest, Jecheon-si, Chungcheongbuk-do, Korea. This site was located at $37^{\circ}12'$ in latitude and $127^{\circ}57'$ in longitude and the period of survey was from March to October, 2004. The vascular plants were summarized as 371 taxa; 83 families, 238 genera, 324 species, 44 varieties and 3 forma. And in the results of survey on resource plants, we confirmed 178 taxa of ornamental plants$(47.98\%)$, 232 taxa of edible plants$(62.53\%)$, 257 taxa of medicinal plants$(69.27\%)$ and 154 taxa of other useful plants$(41.51\%)$. The rare and endangered plants designated by Korea Forest Service were 4 taxa; Eranthis stellata, Paeonia japonica, Viola albida and Scopolia japonica.

• The Journal of the Korea Contents Association
• /
• v.11 no.2
• /
• pp.376-384
• /
• 2011

This study was conducted to determine the effect of major-related volunteering on self-esteem and self-efficiency in fifty three university students who are majoring in occupational therapy. Students volunteered for 20 days in the geriatric service center for dementia from July 27, 2009 to August 21, 2009. Questionnaire survey was conducted to determine the difference in, self-efficiency, career awareness before and after the volunteering. Student showed satisfaction to volunteer program in general, and self-esteem and self-efficiency improved from $29.43{\pm}2.51$ point and $30.45{\pm}3.41$ point to $31.66{\pm}2.63$ point and $33.26{\pm}3.93$ point, respectively. In addition, subjects expressed comfort toward occupational therapy and were able to recognize how to prepare the role of occupational therapist after graduation. These results indicates that occupational therapy-related volunteering was effective in understanding occupational therapy and improving career awareness.

• The KIPS Transactions:PartA
• /
• v.11A no.6
• /
• pp.419-424
• /
• 2004

Mobile Internet using mobile devices provides Portability to users and is Spreading throughout out lives. But Practical use of the mobile Internet is insufficient due to it's fundamental limitations. Especially, mobile resources are not sufficient because they are not closely connected under current mobile Internet services which are provided with pre-designed structure. For these reasons it will take a lot more time and effort for mobile Internet to grow as a popular service. In this paper, we are focusing to overcome the local limitation and to enhance the 'Sharing of Mobile Resources' by expanding mutual connectivity between resource objects scattered over the mobile Internet environment. To archive this, we propose the MRSS(Mobile Resources Sharing System). MRSS automatically converts single request from user to multiple instructions based on 'Context-Awareness' to search for proper information. Using MRSS, we can expect 'Mobile Ubiquitous Computing' environment which users can reach to information anywhere, anytime.