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Bradyscela hoonsooi Song & Min, 2015, new species
No full textBradyscela hoonsooi new species Figures 1 and 2 Holotype and paratypes. In permanent slides, deposited in the collection of the National Institute of Biological Resources, Incheon, Korea (holotype: KOSPIV0000192577; two paratypes: KOSPIV0000192578, and KOSPIV0000192579). Specimens isolated from mosses growing on a tree trunk at Wanggok-ri, collected by Min Ok Song. Type material is further fixed with 4 % formalin after boiling water fixation (Pennak 1978), and preserved in 100 % glycerin (Stemberger 1979). Type locality. Wanggok-ri, Goseong-gun, Gangwon-do, Korea. GPS 38 ° 22 ’ 48.46 ” N / 128 ° 28 ’ 2.78 ” E Material. Five specimens found in mosses growing on a tree trunk at Wanggok-ri, Goseong-gun, Gangwondo. Differential diagnosis. In the genus Bradyscela, only two species, B. clauda (Bryce, 1893) and B. granulosa De Koning, 1947, have previously been described. B. hoonsooi n. sp. seems to be more morphologically similar to B. clauda than to B. granulosa. B. clauda and B. hoonsooi n. sp. have numerous papillae surrounding the posterior margin of the second foot pseudosegment, whereas B. granulosa has two very small spurs, which are usually hidden inside the U-shaped swollen part of the second foot pseudosegment. B. hoonsooi n. sp. can be distinguished from B. clauda by the following morphological characteristics: (1) the number of teeth on the outer margin of the rake apparatus; and (2) the number and shape of papillae around the posterior margin of the second foot pseudosegment. B. hoonsooi n. sp. has four teeth on the outer margin of the rake apparatus, whereas B. clauda has six; B. hoonsooi n. sp. has approximately 42 thin papillae, two thin and knobby papillae, and two thick paddleshaped papillae, whereas B. clauda has approximately 21 short and round-ended papillae and two inverted triangleshaped papillae; and the majority of papillae in B. hoonsooi n. sp. are thinner and much longer than those of B. clauda. Description. Body reddish, highly granulated, and vermiform. Rostral lamella trilobed with auricle-like lateral lobes; each lateral lobe very thin and hexagonal in frontal view; median lobe with variable shapes depending on head movement (flat, arched, or slightly bilobed). Head wider than its length when rake apparatus fully opened, and slightly narrower than maximum body width in creeping. Rake apparatus with four teeth on outer margin and one tooth inside; each corner of outer margin of rake apparatus triangular, variable in shape, from a dull angle to a sharp process depending on the degree of retraction or expansion of the rake apparatus during its grasping action (Fig. 1 b). Dental formula 2 / 2. Pharyngeal tube as long as trophi length. Foot very short, barely extended fully, and with three pseudosegments; posterior margin of second pseudosegment surrounded by approximately 42 thin papillae, and with two thin and round-ended papillae on each ventrolateral corner, and two large paddle-shaped papillae on each dorsolateral corner. Three toes very short, thick, and blunt. Measurements. Total length 200–210 µm. Greatest trunk width 45–50 µm. Rostral lamellae width 21–22 µm. Distribution. The new species is known only from its type locality. Etymology. The species is named after the late Dr. Hoon Soo Kim, Professor Emeritus of the Department of Zoology at Seoul National University, in recognition of his outstanding contribution to invertebrate taxonomy in Korea, as well as his excellent mentoring during the authors’ graduate studies.Published as part of Song, Min Ok & Min, Gi-Sik, 2015, A new species and ten new records of bdelloid rotifers from Korea, pp. 211-227 in Zootaxa 3964 (2) on pages 213-215, DOI: 10.11646/zootaxa.3964.2.3, http://zenodo.org/record/24542
Domestic Demand Driven Growth Pattern of Korean IT Industry: Service-Driven Growth Pattern with Network Externality
No full textInfluence of process parameters on three-dimensional surface coloring
No full text학위논문(석사) - 한국과학기술원 : 기계공학전공, 2005.2, [ x, 88 p. ]산업에서 시작품의 실감재현을 위한 3차원 칼라링 기술이 필요하다. 그러나 기존의 3차원 표면에 칼라를 재현하는 기술은 다른 시작품에 채색할 수 없으며 시간과 비용이 많이 소요된다. 본 연구에서는 잉크젯 헤드를 이용하여 3차원 표면에 채색을 하는 새로운 공정을 제안한다. 공정 개발을 위해 잉크젯 헤드와 기울어진 면사이의 거리와 각도에 따른 인쇄 특성에 대한 실험을 수행하였다. 실험 결과 공정 변수에 따라 인쇄 오차를 최소화할 수 있는 보정 행렬을 제안하고 검증하였다. 곡면에 대한 프린트 특성을 알아보기 위해 선곡면에 대한 실험을 수행하였으며 3차원 곡면 인쇄를 위해 곡률에 따른 단속 거리와 각도를 제안하였다. 이러한 개념은 곡면에서 오차 범위내에 드는 몇 개의 단속적인 분할을 수행하여 분할 곡면을 기울어진 면으로 근사하여 보정 행렬에 따라 이미지를 왜곡하는 것이다. 최종적으로 헬멧 표면에 일반적인 이미지 프린팅 실험을 수행하여 본 연구의 실용성 검증할 수 있었다.한국과학기술원 : 기계공학전공
장주기 운전을 고려한 가압경수로 방사화 부식생성물 평가 연구
No full text학위논문(석사) - 한국과학기술원 : 원자력공학과, 1999.2, [ viii, 52 p. ]Nowadays nuclear power plant operation practice shifts to extended fuel cycle such as from 12 month operating cycle to 18~24 month operating one. It is important to emphasize that the current trend to longer fuel cycles has complicated the dilemma of finding optimum pH range for the primary coolant chemistry. Typically, current 12-month fuel cycles start with no more than 1200ppm boron concentration at the start of a cycle, so a maximum value of 2.2ppm lithium is supplied to satisfy the pH6.9 requirement. The occupational radiation exposure (ORE) increases due to radioactive corrosion products. The recent ICRP recommendation (ICRP publication No. 60) for the radiological protection requires more strict reduction of ORE in the nuclear power plant. The major sources of the radiation are generated by the neutron activation of the non-radioactive corrosion products, that is called CRUD(Chalk River Unidentified Deposit).
To optimize the chemical conditions at the extended fuel cycle, COTRAN code which was developed to simulate the behavior of the radioactive corrosion product(CRUD) was used. COTRAN code was developed to estimate CRUD during only one cycle. This study, however, is to predict corrosion product not for one cycle, but for multi-cycle. In order to predict corrosion products for multi-cycle, COTRAN code is modified for considering decontamination, refueling and applied to KNGR.
The results show that not only selecting the optimum pH but also cycle duration are important parameters reducing the generation of CRUD. It turned out that the activities of CRUD decreases as pH of the coolant increases, and for the same period of different fuel cycle, as the fuel cycle duration increased, the generation of the CRUD increases. As operation cycle duration is increased, the ratio of becomes small. Activities of and shows similar trend to measured activities of those at steam generator tube surface of Millstone Point 3 PWR.
It is...한국과학기술원 : 원자력공학과
원자력발전소에서 발생되는 방사성부식생성물의 자기적 성질을 이용한 제거방법에 관한 연구
No full text학위논문(박사) - 한국과학기술원 : 원자력및양자공학과, 2004.2, [ x, 130 p. ]It is important to emphasize that the current trend to longer fuel cycle (1824 month) has complicated the dilemma of finding optimum chemical condition for the primary coolant because of some problems such as increase of radioactive corrosion product, possibility of axial offset anomaly and so on. Radioactive corrosion products which are generated by the neutron activation of general corrosion products at a nuclear power plant are the major source of occupational radiation exposure.
There are several ways to reduce the radiation levels around the primary water system. For example, improving the coolant purification system, operating at high pH, the adopting materials with low levels of cobalt in the primary coolant system and decontaminating the primary system more frequently. The representative method for CRUD reduction is the high pH operation that controls the deposition of general corrosion products using solubility difference in the primary coolant system. The pH value of 7.4 has been suggested as suitable pH value in many experiments and researches. However, it is difficult to operate on the high pH chemistry at the long term fuel cycle (1824 month cycle) due to high boron concentration. The concentration of lithium that works as chemical agent with boron in order to control pH of the primary coolant is restricted because of possibility of Li-Zr stress corrosion cracking related to nuclear fuel damage. Therefore, it is important to emphasize that current movement to long term fuel cycle has increased the difficulty of pH optimization. Amounts of CRUD generation at long term fuel cycle expect to increase compared to 12 month fuel cycle owing to difficulty of high pH operation.
Not only passive ways for CRUD reduction but also active methods for CRUD removal are required at a long term fuel cycle. During the power operational period, the crud in the primary coolant is generally removed at the chemical volume control system (CVCS), which controls the concent...한국과학기술원 : 원자력및양자공학과
The bending collapse characteristics of aluminum/GFRP hybrid tube
No full text학위논문(석사) - 한국과학기술원 : 기계공학전공, 2001.2, [ vii, 71 p. ]본 논문에서는 알루미늄/GFRP 혼성튜브의 굽힘 붕괴에 대한 특성이 연구되었다. 혼성 튜브는 동시경화법에 의해 제작되었다. 직접 제작한 외팔보 굽힘 붕괴시험 장치를 이용하여 알루미늄 튜브, GFRP 튜브, 알루미늄/GFRP 혼성 튜브의 굽힘 붕괴 시험이 수행되고, 그를 바탕으로 각 시편의 최대굽힘 모멘트와 에너지 흡수 특성이 평가되었다. 혼성 튜브의 경우 0/90˚적층각의 에너지 흡수 특성이 알루미늄에 비해 단위 질량당의 에너지 흡수 특성이 우수하였다. 혼성 튜브는 GFRP나 두꺼운 알루미늄 튜브에서 발생할 수 있는 불안정한 붕괴모드를 혼성 튜브내의 알루미늄 튜브에서의 소성힌지에 바탕을 두고 있는 안정적인 붕괴로 전환시킬 수 있다. 또한 혼성튜브의 굽힘 붕괴 특성을 예측하기 위해 금속 붕괴 모델인 Kecman의 모델을 기초로 혼성 튜브의 붕괴 모델을 제시하였으며, 이는 실험 결과와 잘 일치함을 보인다.한국과학기술원 : 기계공학전공
Control of APC-Cdc20 by the tumor suppressor RASSF1A
No full textThe tumor suppressor gene RASSF1A is frequently hypermethylated in various tumors. However, how RASSF1A functions in tumor suppression was unknown. Our study shows that RASSF1A regulates the stability of mitotic cyclins and the timing of mitotic progression by inhibiting APC-Cdc20. RASSF1A appears to work in early pro-metaphase, after Emi1 destruction and before activation of the Mad2-dependent spindle checkpoint. Loss of RASSF1A expression induces premature APC activation, thereby resulting in acceleration of mitotic cyclin degradation and mitotic progression as well as induction of mitotic abnormalities. Thus, RASSF1A plays a critical role in mitotic progression and tumor suppression by controlling APC-Cdc20 activity
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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