• Applied Microscopy
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• v.37 no.2
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• pp.83-91
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• 2007

The present study examined the epidermal changes of adhesive disks which occur during attachment in Parthenocissus tricuspidata using scanning and transmission electron microscopy. Several adhesive disks, each covered with a bract, develop from the shoot apical meristem during early development. In the initial stage, the adhesive disks are club-shaped and their upper and lower epidermis are indistinguishable. However, in the actively growing stage, they become spherical and both epidermis are clearly differentiated into the adventitious roots. Prior to wall attachment, the adhesive disks exhibit adaxial convex and abaxial concave shapes, and electron-dense substances are abundant in the vacuoles of epidermal cells. The peripheral area of the adhesive disk is adhered first to the wall surface, while the central area is drawn inward in a vacuum-like state during attachment. As the attachment progresses and the electron-dense substances continue to discharge, the upper and lower epidermis rapidly undergo deterioration and the disks shrink considerably. At this stage, structural changes of the lower epidermis occur much faster than in the upper one. The discharged substance is accumulated on the wall surface, and this aids the attachment of adhesive disks on the wall for long periods. In this manner, the shape and structure of the adhesive disk epidermis change drastically from initial growth to the mature stage. Further, the role of electron-dense substance and shrinkage of the disk during attachment has been discussed in Parthenocissus tricuspidata.

• Journal of Bio-Environment Control
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• v.14 no.2
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• pp.95-105
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• 2005

This study was carried out to file up using effect and requirement of energy for environmental design data of Pleurotus eryngii growing houses. Heating and cooling Degree-Hour (D-H) were calculated and compared for. some Pleurotus eryngii growing houses of sandwich-panel (permanent) o. arch-roofed(simple) type structures modified and suggested through field survey and analysis. Also thermal resistance (R-value) was calculated for the heat insulating and covering materials of the permanent and simple-type, which were made of polyurethane or polystyrene panel and $7\~8$ layers heat conservation cover wall. The variations of heating and cooling D-H simulated for Jinju area was nearly linearly proportional to the setting inside temperatures. The variations of cooling D-H was much more sensitive than those of heating D-H. Therefore, it was expected that the variations of required energy in accordance with setting temperature or actual temperature maintained inside of the cultivation house could be estimated and also the estimated results of heating and cooling D-H could be effectively used far the verification of environmental simulation as well as for the calculation of required energy amounts. When the cultivation floor areas are all equal, panel type houses to be constructed by various combinations of materials were found to by far more effective than simple type pipe house in the aspect of energy conservation maintenance except some additional cost invested initially. And also the energy effectiveness of multi-span house compared to single span together with the prediction of energy requirement depending on the level insulated for the wall and roof area could be estimated. Additionally, structural as well as environmental optimizations are expected to be possible by calculating periodical and/or seasonal energy requirements for those various combinations of insulation level and different climate conditions, etc.

• Journal of Legislation Research
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• no.41
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• pp.401-434
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• 2011

The discussion on the adoption of the horizontal regulatory framework is underway to overcome the problems regarding the vertical regulatory framework resulting from a convergence of broadcasting and telecommunications services. Recently, however, the horizontal regulatory framework shows its limitation to regulate the ecosystem established mainly by Google and Apple. The existing horizontal regulatory framework does not fully reflect the characteristics of the two-sided market and the change in the competition structure in the broadcasting and telecommunications sector. What is important to note is that if the existing horizontal regulatory framework is simply applied to the ecosystem, a regulatory imbalance can be caused among ecosystems. The existing horizontal regulatory framework, which is subject to a value chain structure, categorizes business entities into either contents layer or transmission layer and applies the same regulation to all business entities in the same category. However, in the ecosystem, a keystone-player can be categorized into different layers depending on its strategy. Therefore, if the existing horizontal regulatory framework is applied as it is, the regulatory imbalance between keystone-players located in less regulated areas and keystone-players located in more regulated areas occurs resulting in a distortion of competition. There are two possible ways to establish a new regulatory framework to prevent the distortion of competition likely to be caused by the adoption of a horizontal regulatory system. First, a new ecosystem regulatory framework different from the existing one can be established. Second, the horizontal regulatory framework can be modified to reflect the ecosystem elements. The first approach is hard to adopt given the current situation as the approach requires the analysis of all broadcasting and telecommunications ecosystems including mobile and wired services; currently research and study on the competition conditions in the ecosystems is not enough. Therefore, this paper supports the second approach proposing a modified horizontal regulatory framework through the improvement of institutions and remedies suitable for accommodating the ecosystem elements. This paper intends to propose a way to regulate broadcasting and telecommunications ecosystems taking into consideration the ecosystem elements on top of the Telecommunications Business Act, Broadcasting Act, IPTV Act, the competition condition evaluation system of the Basic Act on Broadcasting and Telecommunications Development, and regulation on common carriers under the Telecommunications Business Act.

• Korean Journal of Heritage: History & Science
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• v.52 no.3
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• pp.74-93
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• 2019

The Bird Track Site in the Haman Formation in Yongsanri (Natural Monument No. 222) was reported on the named Koreanaornis hamanensis and Jindongornipes kimi sauropod footprint Brontopodus and ichnospecies Ochlichnus formed by Nematoda. This site has outstanding academic value because it is where the second-highest number of bird tracks have been reported in the world. However, only 25% of the site remains after being designated a natural monument in 1969. This is due to artificial damage caused by worldwide fame and quarrying for flat stone used in Korean floor heating systems. The Haman Formation, including this fossil site, has lithofacies showing reddish-grey siltstone and black shale, alternately. The boundary of the two rocks is progressive, and sedimentary structures like ripple marks and sun cracks can clearly be found. This site was divided into seven formations according to sedimentary sequences and structures. The results of a nondestructive deterioration evaluation showed that chemical and biological damage rates were very low for all formations. Also, physical damage displayed low rates with 0.49% on exfoliation, 0.04% on blistering, 0.28% on break-out; however, the joint crack index was high, 6.20. Additionally, efflorescence was observed on outcrops at the backside and the northwestern side. Physical properties measured by an indirect ultrasonic analysis were found to be moderately weathered (MW). Above all, the southeastern side was much fresher, though some areas around the column of protection facility appeared more weathered. Furthermore, five kinds of discontinuity surface can be found at this site, with the bedding plane showing the higher share. There is the possibility of toppling failure occurring at this site but stable on plane and wedge failure by means of stereographic projection. We concluded that the overall level of deterioration and stability were relatively fine. However, continuous monitoring and conservation treatment and management should be performed as situations such as the physicochemical weathering of the fossil layer, and the efflorescence of the mortar adjoining the protection facility's column appear to be challenging to control.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.29 no.1
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• pp.56-76
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• 2024

We for the first time made a successful longest continuous sectional observation in the East Sea by an underwater glider during 95 days from September 18 to December 21 2020 in the Korea along the 106 Line (129.1 °E ~ 131.5 °E at 37.9 °N) of the regular shipboard measurements by the National Institute of Fishery Science (NIFS) and obtained twelve hydrographic sections with high spatiotemporal resolution. The glider was deployed at 129.1 °E in September 18 and conducted 88-days flight from September 19 to December 15 2020, yielding twelve hydrographic sections, and then recovered at 129.2 °E in December 21 after the last 6 days virtual mooring operation. During the total traveled distance of 2550 km, the estimated deviation from the predetermined zonal path had an average RMS distance of 262 m. Based on these high-resolution long-term glider measurements, we conducted a comparative study with the bi-monthly NIFS measurements in terms of spatial and temporal resolutions, and found distinguished features. One is that spatial features of sub-mesoscale such as sub-mesoscale frontal structure and intensified thermocline were detected only in the glider measurements, mainly due to glider's high spatial resolution. The other is the detection of intramonthly variations from the weekly time series of temperature and salinity, which were extracted from glider's continuous sections. Lastly, there were deviations and bias in measurements from both platforms. We argued these deviations in terms of the time scale of variation, the spatial scale of fixed-point observation, and the calibration status of CTD devices of both platforms.

• Cartoon and Animation Studies
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• s.37
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• pp.197-219
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• 2014

, one of the Disney's animations, hit the 10 million audience mark for the first time in the history of animations released in Korea. not only raised the fever with its theme song, 'Let it go', as well as Elsa, Anna, and Olaf's character products but caused sensations in many ways. If so, we need to think about what kind of meaning did create in Korea to be so sensational. This study examines the value that Frozen intended to deliver and the meaning it generated by using Greimas actant model and semiotic square. From the actant model analysis on Anna and Elsa from , it was identified that Anna desired to recover her relationship with Elsa and to take summer back in Arendelle. Her desires can be interpreted as her love toward Elsa and people in Arendelle. Meanwhile, Elsa always desired freedom although she confined herself because of her ability to freeze. In other words, Elsa desired to free herself from her freezing ability by finding out how to control her ability. Such desires of Anna and Elsa were achieved by their actions of true love, and the solution of all the conflicts in was an action of true love. From the semiotic square analysis on the meaning of , it was found out that created past-oriented value with which characters tried to change their abnormal lives of the present into their normal lives of the past. The characters tried to change their present lives where freezing winter comes in the middle of summer, communication between the sisters is cut off, and people try to take advantage of the abnormal state deliberately, into the past when the sisters had a good relationship and the natural season of summer in Arendelle. The past-oriented value that tried to tell us is similar to our reality. In our reality with a lot of unbelievable news and unstable circumstances, we desire to go back to the past when we were filled with affection and hope even though our lives were tough and difficult. This sentiment must have contributed to the huge success of in Korea.

• Progress in Medical Physics
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• v.27 no.1
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• pp.14-24
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• 2016

Since the head and neck region is densely located with organs at risk (OAR), OAR-sparing is an important issue in the treatment of head and neck cancers. This study-in which different treatment plans were performed varying the head tilt angle on brain tumor patients-investigates the optimal head elevation angle for sparing normal organs (e.g. the hippocampus) and further compares the dosimetric characteristics of different types of radiation equipment. we performed 3D conformal radiation therapy (3D-CRT), intensity-modulated radiation therapy (IMRT), and tomotherapy on 10 patients with brain tumors in the frontal lobe while varying the head tilt angle of patients to analyze the dosimetric characteristics of different therapy methods. In each treatment plan, 95% of the tumor volume was irradiated with a dose of 40 Gy in 10 fractions. The step and shoot technique with nine beams was used for IMRT, and the same prescription dose was delivered to the tumor volume for the 3D-CRT and tomotherapy plans. The homogeneity index, conformity index, and normal tissue complication probability (NTCP) were calculated. At a head elevation angle of $30^{\circ}$, conformity of the isodose curve to the target increased on average by 53%, 8%, and 5.4%. In 3D-CRT, the maximum dose received by the brain stem decreased at $15^{\circ}$, $30^{\circ}$, and $40^{\circ}$, compared to that observed at $0^{\circ}$. The NTCP value of the hippocampus observed in each modality was the highest at a head and neck angle of $0^{\circ}$ and the lowest at $30^{\circ}$. This study demonstrates that the elevation of the patients' head tilt angle in radiation therapy improves the target region's homogeneity of dose distribution by increasing the tumor control rate and conformity of the isodose curve to the target. Moreover, the study shows that the elevation of the head tilt angle lowers the NTCP by separating the tumor volume from the normal tissues, which helps spare OARs and reduce the delivered dose to the hippocampus.

• Korea journal of population studies
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• v.17 no.1
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• pp.87-114
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• 1994

1950년대부터 많은 개발도상국가들은 가족계획을 위주로 하는 인구제어정책을 추진하여 왔다. 특히 가부장제도를 중심으로하는 동아시아 국가들에 있어서는 남아선호관이 출산력 저하나 피임 실천율이 증대에 지대한 유해요인으로 일관해 왔다. Sheps(1963)는 실증적으로 2명의 아들을 갖기 위해서는 약 3.9명 정도의 자녀를 두어야 한다는 연구결과를 제시한바 있다. 이와 같은 남아선호관의 여파에도 불구하고 한국과 홍콩은 1980년대 증반에 이미 1.6명 수준의 저출산율을 이룩하였으며, 1970년대에 인구억제 정책을 시작한 중국도 2명 수준으로 저하되어 가족계획사업의 성공사례로 평가되어 왔다. 그러나 이들 국가들의 출산율은 지난 20-30년이라는 짧은 기간에 너무나 급진적으로 감소된 반면에 남아선호관의 상존으로 인한 성비(여자 100명당 남자수)의 불균형을 초래하게 되였다. 한 예로 한국의 경우 1960년도만 해도 6명 이상의 자녀를 출산하는 과정에서 1-2명의 아들을 둘 수 있는 확률은 매우 높았으나, 최근에는 출산율이 2명 이하로 저하되어 아들을 둘 수 있는 확률은 과거보다 3-4배 어려워졌기 때문에 인위적인 방법으로 아들을 두는 부모의 수가 증가하고 있다. 중국은 1970년대 중반기부터 강력히 추진되어온 소위 "한자녀 갖기 운동"으로 인하여 여아출산인 경우 영아살해 또는 출생의 미신고등 많은 사회적 물의를 야기하였고, 최근에는 초음파검사를통한 선택적 인공임신중절(태아가 여아인 경우)으 경우가 급격히 증가하고 있다. 우리 나라의 성비는 출산율이 급격히 감소된 1980년대 증반기부터 급격히 증가되었다. 즉 인구전체에 대한 성비는 1980년의 103.9명에서 1985년에 110명으로 증가하였고ㅡ 1990년 116.9명으로 증가되었다. 성비는 자녀의 수가 적을수록 높아지는 추세이다. 1991년 조사에서 출산을 종료한 부인의 경우 1자녀의 성비는 무려 206명이나 되고 있다. 이와 같은 결과는 한자녀를 원하는 부인이 아들을 둔 경우 1자녀에서 조산을 결심하기 때문인 것이다. 통계청 자료에 의하면 성비는 무엇보다도 자녀의 출산순위와 밀접하다. 1991년 출생신고자료의 경우 첫아이의 출생시 성비는 106.1명이고, 둘째아이가 112.8명이나, 셋째아이는 184.7명으로 크게 증가하고 넷째 이상의 경우는 212.3명이나 된다. 동일한 출산순위라도 이미 두고 있는 자녀의 성에 따라서 많은 차이를 보인다. 1991년도 3번째 출산의 경우 딸만 2명을 두고 있는 자녀의 성에 아들만 2명 또는 아들과 딸을 각각 1명씩 두고 있는 경우에 비해 높은 성비를 보이고 있다. 자녀를 출산하는데 있어서 처음에는 아들ㅇ르 기다리지만 딸의 수가 증가함에 따라 적극적으로 아들을 낳고자 하는 노력을 지속하게 됨을 알 수 있다. 이는 즉 임신한 자녀의 성이 딸로 판명되면 인공임신중절을 통해 임신을 종결시키고 있음을 의미한다. 최근 한국보건사회연구원에서 수행한 연구결과에 의하면 이미 출생한 자녀의 성구성은 임신결과를 결정하는 가장 중요한 변수로 부각되고 있다. 즉 임신이 인공임신중절로 귀착되는 확률은 부모가 이미 아들을 두고 있는 경우에 일관성 있게 증가되고 있음을 보이고 있다. 따라서 남아선호관은 임신결과를 결정할뿐 아니라 선택절 인공임신중절에 의한 성비의 불균형을 초래하는 주요 변수로써 할거되었다. 특히 피임실천이 보편화되고 선택적 인공임신중절의 이용이 손쉬운 현대사회에 있어서는 남아선호관이 출산력 저하에 저해요인으로서가 아니라, 인위적이던 자연적이던 간에 아들만 두면 단산하는 현행의 출산풍토하에서는 남아선호관이 오히려 출산력저하에 결정적으로 작용하고 있다고 하겠다. 태아의 성 판별을 통한 선택적 인공임신중절의 건수는 1990년 한해에 약 20,000건 정도가 되고, 1986-1990년 사이에 총 80,000건으로 추정된다. 이 수치는 출생한 여아수의 5%에 해당한다. 현재 출생시 성비의 불균형은 연간 총출생수의 10% 미만에 불과한 3번째 이상의 출산에서 발생되고 있기 때문에 인구학적인 측면에서는 큰 문제가 아니다. 그러나 앞으로 출산율의 감소와 더불어 선택적 인공임신중절이 년간 출생수의 90% 이상을 차지하고 있는 둘째, 첫째출산순위로 확산된다면 성비의 불균형은 급진적으로 가속화되어 전통적 결혼관습의 재연등 인간의 생태계를 파괴하는 새로운 차원에서의 사회인구학적인 문제가 야기될 것이다. 결론적으로 성비의 불균형을 초래하는 근본적인 원인은 우리 나라으 전통적인 의식구조인 남아선호관의 상종과 최신의 의료기술에 의한 선택적 인공임신중절에 기인된 것이기 때문에 이를 시정하기 위한 제반 사회제도적 극복정책은 지속적으로 강화되어야 할 것이다.되어야 할 것이다.

• KIPS Transactions on Computer and Communication Systems
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• v.6 no.1
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• pp.1-8
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• 2017

Communications for mobile sink groups such as rescue teams or platoons bring about a new challenging issue for handling mobility in wireless sensor networks. To do this, many studies have been proposed to support mobile sink groups. When closely looking at mobile sink groups, they can be divided into (multiple) small groups according to the property of applications. For example, a platoon can be divided into multiple squads to carry out its mission in the battle field. However, the previous studies cannot efficiently support the division of mobile sink groups because they do not address three challenging issues engendered by the mobile sink group division. The first issue is to select a leader sink for a new small mobile sink group. The efficient data delivery from a source to small mobile sink groups is the second issue. Last, the third issue is to share data between leader sinks of small mobile sink groups. Thus, this paper proposes a routing protocol to efficiently support the division of mobile sink groups by solving the three challenging issues. For the first issue, the proposed protocol selects a leader sink of a new small mobile sink group which provide a minimum summation of the distance between the new leader sink and the previous leader sink and the distance from the new leader sink to all of its member sinks. For the efficient data delivery from a source to small mobile sink groups in the second issue, the proposed protocol determines the path to minimize the data dissemination distance from source to small mobile sink group by calculating with the location information of both the source and the leader sinks. With regard to the third issue, the proposed protocol exploits member sinks located among leader sinks to provide efficient data sharing among leaders sinks by considering the location information of member sinks. Simulation results verified that the proposed protocol is superior to the previous protocol in terms of the energy consumption.

• Journal of Korean Society for Atmospheric Environment
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• v.24 no.2
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• pp.196-205
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• 2008

Variability in vertical ozone and meteorological profiles was measured by 2Z electrochemical concentration cells (ECC) ozonesonde at Bangyi in Seoul ($37.52^{\circ}N$, $127.13^{\circ}E$) during June $6{\sim}9$, 2003 in odor to identify the vertical distribution of ozone and its relationship with the lower-atmospheric structure resulted in the high ozone concentrations near the surface. The eight profiles obtained in the early morning and the late afternoon during the study period clearly showed that the substantial change of ozone concentrations in lower atmosphere(${\sim}5\;km$), indicating that it is tightly coupled to the variation of the planetary boundary layer (PBL) structure as well as the background synoptic flow. All profiles observed early in the morning showed very low ozone concentrations near the surface with strong vertical gradients in the nocturnal stable boundary layer due to the photochemical ozone loss caused by surface NO titration under very weak vertical mixing. On the other hand, relatively uniform ozone profiles in the developed mixing layer and the ozone peaks in the upper PBL, were observed in the late afternoon. It was noted that a significant increase in ozone concentrations in the lower atmosphere occurred with the corresponding decrease of the mixing height in the late afternoon on June 8. Ozone in upper layer did not vertically vary much compared to that in PBL but changed significantly on June 6 that was closely associated with the variation of synoptic flows. Interestingly, heavily polluted ozone layers aloft (a maximum value of 115 ppb around 2 km) were formed early in the morning on 6 through 7 June under dominant westerly synoptic flows. This indicates the effects of the transport of pollutants on regional scale and consequently can give a rise to increase the surface ozone concentration by downward mixing processes enhanced in the afternoon.